The present invention concerns a method of machining rotationally symmetrical parts to put them into the condition in which they are capable of use, wherein the parts in the course of the manufacturing procedure are at least partially subjected to a hardening procedure. In particulars this concerns crankshafts, in particular the bearing surfaces (both of the big-end bearings and also the fitting bearings, the sealing bearings and central bearings) of crankshafts, in regard to which the condition in which they are capable of use is that condition in which the crankshaft can be fitted in the engine without further removal of material at the bearing surfaces. In that respect bearing surfaces is used to denote both the peripheral surfaces, that is to say the bearing diameter, and also the surfaces which are referred to as the mirror or thrust surfaces, that is to say the end faces which adjoin the peripheral surfaces generally in perpendicular relationship and which serve for example for axial thrust support. In this respects particularly in the case of steel crankshafts, the bearing surfaces are hardened in the regions thereof which are in the proximity of their surface. That serves both for increased resistance to abrasive wear of the bearing locations, and also serves to protect those bearing surfaces from damage in the course of handling throughout the entire manufacturing procedure as well as serving to influence the strength properties involved.
Crankshafts, in particular the crankshafts for private motor vehicles which have a large number of cylinders, are known to be workpieces which are unstable during machining and thus difficult to machine. Assessment of the dimensional accuracy of a finished crankshaft is effected primarily, besides the axial bearing width, by assessment of the following parameters:
Diameter deviation, which is deviation from the predetermined reference or target diameter of the bearing journal,
roundness, which is macroscopic deviation from the round reference or target contour of the bearing journal,
concentricity, which is a diameter deviation in the case of a rotating workpiece, that is to say, for example, the deviation from the reference positional contour which a main bearing location effects during the rotary movement of the crankshaft by virtues on the one hands of the non-ideal roundness of that main bearing journal and, on the other hand, of flexing of the crankshaft which in that case is clamped only at its ends,
roughness Ra, which is a value which is ascertained by calculation and which represents the microscopic roughness of the surface of the bearing location, and
percentage contact area, which is the load-bearing surface proportion of the surface structure, considered microscopically, which comes into contact with a co-operating or counterpart surface pressed thereon.
In addition, in regard to the big-end bearing locations, there is an assessment of:
stroke deviation, which is the dimensional, percentage deviation of the actual stroke (spacing of the actual center of the big-end bearing journal from the actual center of the main bearings), from the reference or target stroke, and
angle deviation, which is the deviation of the actual angular position of the big-end bearing journal from its reference or target angular position relative to the main bearing axis and with respect to the angular position in relation to the other big-end bearing journals, the angle deviation being specified in degrees or as a length dimension in the peripheral direction, related to the stroke.
Observing the desired tolerances in regard to those parameters is made difficult less due to the available machining methods than the instability of the workpiece and the machining forces involved. The efficiency and economy of the method also play a large part in a practical context.
Hitherto the removal of material from the bearing locations on the crankshaft in its original form, that is to say as cast or forged, was effected in succession in four machining steps:
First Step:
Cutting machining with a given cutting edge; this involved using the processes of turning, rotary broaching, turning-rotary broaching, internal round milling and external milling, rotary milling, in particular in the form of high-speed milling or combinations of such procedures. The magnitude of the material to be removed was in the millimeter range.
Second Step:
Hardening of the desired regions, in particular the bearing surfaces, wherein heating and subsequent cooling of the crankshaft and the change in the material and configurational structure, in particular due to the irregular way in which those procedures take place, causes distortion and dimensional variation of the crankshaft or one of the regions thereof, and that has to be compensated by the subsequent operations of removing material, in consideration of the reference or target dimensions of the final condition.
Third Step:
Grinding by means of a hard, massive grinding tool, for example a grinding wheel, which generally rotates with its axis of rotation in parallel relationship with the axis of rotation of the crankshaft to be machined; the amount of material to be removed was in the tenths-of-millimeter range.
In the case of crankshafts which are difficult to machine, in particular crankshafts which are long and thus highly unstable, the grinding machining operation was also effected in a multi-stage procedure, for example in a two-stage procedure by preliminary and finishing grinding.
Fourth Step:
Finishing by generally a stationary grinding means (grinding belt or grinding stone) which is pressed against the external periphery of the rotating bearing location; the amount of material to be removed is at the present time in the range of hundredths of a millimeter or even mm.
In that respect, a distinction is also to be drawn in regard to the machining operation, in respect of the material of the crankshaft (steel or cast iron), in which connection in particular steel crankshafts which are preferably used for situations of use involving a high loading are hardened after the cutting machining operation.
In order to reduce the costs involved in crankshaft machining, the endeavour is to reduce the machining of the bearing locations from four to three different machining stages.
This means however when the cutting machining operation is omitted that in particular the removal of material which is to be implemented by the grinding operation must be greater than in the case of the four-stage method.
Removing material by means of grinding however involves the following disadvantages:
because of the cooling/lubricating agent which is to be added, the grinding slurry which is produced gives rise to problems and is extremely costly to dispose of,
because of the oil contained in the cooling/lubricating agent, for example in the case of CBN-grinding, there is always a latent risk of explosion,
in the grinding operation the amount of cooling/lubricating agent used is substantially greater than in the case of cutting machining procedures as the cooling/lubricating agent is additionally employed in order to remove the grinding dust and swarf from the surface of the grinding wheel again, by jetting the cooling/lubricating agent on to same under high pressure,
nonetheless the danger of the workpiece suffering from overheating is very high,
the machining pressures acting on the workpiece are higher than in the case of cutting machining, and
a microscopic surface structure is produced, in which the grain boundaries which are torn open by the grinding grain are smeared closed again by the subsequent grinding grains, with removed workpiece material, that is to say this is a surface structure with relatively few steep peaks, but with more or less flat, bent-over peaks which partly overlap in scale-like relationship.
A primary object of the invention is to simplify the removal of material when machining bearing locations on a crankshaft to be hardened.
This object is attained by virtue of the grinding machining operation being omitted so that the machining sequence is reduced from four to only three machining procedures which are, in principles different. This eliminates not only all disposal problems in regard to the grinding slurry or swarf, but also the quite considerable capital investment costs for grinding machines, the costs involved in tool consumption and not least the required stock of workpieces, which is increased due to the grinding operation, by virtue of prolonged turn-around times for the workpieces. Disposal of the cuttings or swarf from the cutting machining operation does not give rise to any problems as either cutting is effected dry (high-speed milling) or separation of oil and cuttings or swarf is entirely possible by virtue of the much lower specific surface area of the cuttings or swarf in relation to grinding dust.
So that, in the procedure for removing material, the finishing operation can directly follow the cutting machining operation with a given cutting edge, hereinafter referred to for the sake of brevity as cutting machining, the degree of the admissible deviation of the actual values from the reference or target values, as occur after the cutting machining operation, must be so established that, in the totality of the machining procedures (cutting machining+finishing), the complication and expenditure involved must be technically as low as possible, with at the same time an overall machining time that is as short as possible.
Under some circumstances it is also possible to effect cutting machining with such a good final result that it is possible completely to omit the finishing operation. Overall the present invention therefore concerns the following combinations of processing sequences until the condition in which, for example, the crankshaft is capable of use is achieved:
cutting-hardening-cutting-finishing
cutting-hardening-cutting
cutting-hardening-finishing
cutting-hardening.
In that respect it is not sufficient in the cutting machining operation to strive for reference or target dimensions which come as close as possible to the final dimensions after the finishing operation, so that the oversizes which are to be dealt with by finishing and thus by relatively slow removal of material can remain as small as possible.
It must be taken into account that the stroke deviation and the angle deviation of the big-end bearing journals can no longer or can be only very slightly compensated by the finishing operation.
It must also be borne in mind that in the finishing operation in any case firstly the amounts of material that can be removed (reduction in diameter) are very small, that is to say up to about 200 mm can be achieved at economically viable expense and in addition secondly the finishing operation primarily provides for an increase in the percentage contact area, more specifically by a reduction in roughness, with the aim of achieving a percentage contact area of about 95%. A percentage contact area of 100% is unwanted as then there would no longer be any depressions which are necessary in order to maintain a film of lubricant at the bearing.
In regard to the microscopic surface structure, the cutting machining operation gives a surface in which the grain boundaries are partially torn open by virtue of the cutting edge pulling the grains apart as it cuts through the material. As a result the surface has a relatively large number of pointed raised portions, interrupted by valleys in the form of opened grain boundaries. A surface structure of that kind is conducive to the finishing operation by virtue of the fact that the many pointed raised portions not only facilitate the removal of material by the finishing procedure, but at the same time they also delay clogging of the finishing belt and the like member which is used in the finishing operation, insofar as the pointed raised portions of the workpiece surface provide that the material which is already deposited in the finishing belt is partially torn out of same again.
The limitations of this procedure are already encountered in the operation of reducing roundness deviations by finishing, insofar as the amount of time involved or the roundness deviations which can be dealt with depend not only on the absolute value of the roundness deviation to be equalised or levelled, but also the configuration thereof:
If the non-roundness is such that there are only a few (for example 2-3) troughs and raised portions, distributed over the periphery (thus constituting long-wave non-roundness), then, with the same absolute value in terms of non-roundness, for equalisation by means of finishing, a substantially greater amount of time is required or, under some circumstances, it is not possible to provide for complete equalisation, in comparison with short-wave non-roundness involving about 5 and preferably even about 30 or more troughs per periphery of the bearing location, with the same absolute value in respect of non-roundness.
It is also to be borne in mind that in the finishing operation at the same time on the one hand the degree of roughness is reduced and thus the percentage contact area is improved, while on the other hand the existing non-roundness is equalised or levelled. Those two effects can scarcely be decoupled from each other, or can be decoupled only to a very limited extent. If therefore, starting from an initial roughness, the desired roughness is achieved in the finishing operation after a given period of time, the finishing procedure is stopped as a given percentage contact area should not be exceeded. The equalisation or levelling effect in respect of the roundness deviation, which is achieved in that condition, is then accepted as a final result, and cannot be advanced separately any further.
Accordingly, if the procedure is commenced from a given initial condition in respect of those two parameters from the finishing operation, roughness and percentage contact area cannot be machined independently of each other to afford desired final values.
For the direct succession of the finishing operation after the cutting machining operation therefore what is recommended is in particular specific coupling of the input parameters in regard to the finishing operation and therewith the output parameters in regard to the cutting machining operation, in respect on the one hand of the absolute value and degree of roundness deviation and on the other hand in respect of microscopic roughness and the percentage contact area which applies in that case.
In the cutting machining procedure using turning methods and also rotary broaching methods and possibly also when using slow milling methods, long-wave roundness deviations rather occur by virtue of long-wave oscillations in the machine structure, the tools and the workpieces involved in cutting machining. In contrast more especially high-speed external milling gives rise to short-wave roundness deviations. Therefore, the use of high-speed external milling in which an external round milling tool of a diameter of about 700 cm, which is very large in diameter in comparison with the crankshaft, rotates at a cutting speed of between 150 and 1000 m/min beside the relatively slowly rotating workpiece about an axis which is parallel with respect to the crankshaft means that it is possible to achieve roundness deviations with many raised portions along a circumference of a bearing.
Rotary milling, in particular if it is implemented with high cutting speeds, also rather tends to involve short-wave oscillations and thus short-wave roundness deviations. For, rotary milling involves milling with a kind of end-milling cutter which is arranged in parallel displaced relationship with respect to the radial direction of the peripheral surface, which is to be machined, of the bearing location, insofar as the peripheral surface is machined by means of the one or some cutting edges arranged on the end of the end-milling cutter. In that case, in particular machining with only one single cutting edge has been found to be advantageous if in that case operation is implemented with very high speeds of milling cutter rotation and the workpiece rotates comparatively slowly. If in that case the above-mentioned mirror surfaces or thrust surfaces of a bearing location are also to be subjected to machining, the end-milling cutter is also provided with one or more cutting edges on its peripheral surface.
It must also be taken into account that, in the finishing operation, the grinding means which bears against the workpiece, for example a finishing belt, is generally not changed during the procedure. The grinding means therefore becomes increasingly clogged at its surface during the finishing operation and the amount of material removed per unit of time progressively decreases.
How fast the grinding means begins to suffer from clogging in particular at the beginning of the finishing operation depends not only on the initial roughness of the surface but also on the percentage contact area thereof:
The lower the percentage contact area with a given level of roughness at the beginning of the finishing operation, that is to say the more pointed the microscopic surface structure is with correspondingly steeper flanks, then all the more readily can the material particles which have been removed from the surface and deposited in the finishing belt be removed from the finishing belt or the finishing stone or comparable finishing means at the beginning, when dealing with such a surface structure. With increasing equalisation or levelling of the microscopic surface the surface of the grinding means also becomes progressively more quickly clogged in the finishing operation.
This means that, with the same degree of roughness, a percentage contact area which is low at the beginning of the finishing operation is advantageous for high initial removal of material and thus a finishing operation which is short in time.
This also means that the degrees of roughness which can be handled by the finishing operation increase, in inverse proportion to the percentage contact area involved with those greater levels of roughness.
With the previous grinding operation, which was always effected following hardening, the roughness of the surface was admittedly reduced in comparison with preliminary cutting machining, but in-that respect in the same way the percentage contact area was either kept constant or even increased as the preliminary cutting machining operation left behind a microscopic surface structure which involves a low percentage contact area as machining with the given cutting edge, in the regions near the surface, means that in part the grain boundaries in the metal structure are torn open, extending radially from the outside inwardly.
In that way it is possible to finish in an economic fashion directly after the cutting machining operation insofar as efficient removal of material in the finishing operation is promoted and assisted by the preliminary machining procedure, insofar as on the one hand the choice of the correct cutting machining procedure means that the roughness achieved in that case has a low percentage contact area, and the roundness deviation achieved in that case is a roundness deviation which is as short-wave as possible.
In that respect it must further be taken into consideration that, in the previous grinding of bearing locations, the roundness deviations resulting from the preliminary cutting machining were generally only reduced by the grinding operation in terms of their absolute value but not in terms of their characteristic. Therefore, the grinding operation did not result in long-wave roundness deviations becoming short-wave roundness deviations, but the number of troughs was either retained or even reduced, with the consequence that a further improvement in roundness deviations by the finishing operation, considered as an improvement in result per unit of time, was made rather more difficult in the finishing procedure.
That means that a finishing operation directly after the cutting machining procedure is particularly economical when, after the cutting machining operation, the roundness deviations are less than 60 mm and in particular less than 40 mm, the diameter deviation is less than 200 mm, in particular less than 150 mm and the roughness Ra is less than 10 mm, in particular less than 6 mm. In that respect, the aim to be sought is roundness deviations with a short-wave nature of at least 5 waves per circumference, which applies in regard to bearing diameters of about 50 mm, but which, with rising or falling bearing diameters, should only change in a sub-proportional fashion, that is to say for example a 100% change in circumference produces only a maximum 30% change in the number of waves.
Furthermore, in that respect, the aim to be sought is a rather lower percentage contact area in respect of the roughness achieved after the cutting procedure, than is obtained after the grinding procedure.
In the case of big-end bearings in addition the angle deviation after the cutting machining operation should be less than 0.4xc2x0, in particular less than 0.2xc2x0, and the stroke deviation should be less than 0.40%, in particular less than 0.20%, which corresponds to the tolerances to be observed in regard to the crankshaft when ready for use, as those parameters can no longer be changed in an economically viable manner by the finishing operation.
A suitable form of the cutting machining procedure is therefore external milling or rotary milling, in particular in the form of high-speed milling, in consideration of the above-described interrelationships.
Particularly when dealing with heavy workpieces, it can be found that a combination of the deviations between reference or target values and actual values of the relevant parameters, such deviations occurring after the cutting machining operation and prior to the finishing operation, wherein such combination is desirable in terms of direct coupling of cutting machining and finishing, can only be achieved if the cutting machining procedure is effected in a plurality of stages, in particular in two stages (preliminary cutting and finishing cutting). In that respect, high-speed external milling or high-speed rotary milling is to be preferred both when dealing with big-end bearings and also when dealing with main bearings, for the second stage, the finishing cutting operation.
The first stage, the preliminary cutting operation, when dealing with big-end bearings will also be effected using external milling, in particular using high-speed external milling, while when dealing with main bearings this can also be effected by turning or rotary broaching or turning-rotary broaching.
If the cutting operation is implemented in two or even more stages, the oversizes which are to be dealt with in the finishing cutting operation range in the optimum fashion between 0.1 and 0.4 mm in order further to improve in particular roundness and diameter deviation by virtue of the removal of very thin cuttings or swarf and in order to achieve a roughness which remains as equal as possible in the course of each individual step in the high-speed milling procedure, with the percentage contact area remaining uniformly low, from a microscopic point of view.
Whether hardening is effected only after conclusion of the single-stage or two-stage cutting machining procedure, and material can be removed after the hardening operation only by means of finishing, depends primarily on the extent of the distortion which occurs in the hardening operation. The distortion depends on a series of individual factors such as configuration and dimensioning of the crankshaft, the nature of the hardening process, whether relatively small or relatively large surface regions or indeed the entire surface are or is hardened, the depth of penetration of the hardening procedure and the configuration in respect of time of the hardening procedure, and so forth. In that respect the probable maximum distortion which occurs in the hardening operation, together with that after the last cutting machining step effected prior to the hardening operation, is not to exceed the threshold which can be managed at commercially acceptable cost by finishing.
On the other hand after the hardening operation a material-removal step is again implemented by cutting machining, in particular the second cutting machining step (finishing cutting) of a two-stage cutting procedure.
As the removal of material in the cutting machining operation is more difficult after hardening than when working on the unhardened workpiece, in this case the oversize which is to be dealt with by the finishing cutting operation in the hardened condition is kept at a small level.
The use of belt-type finishers is recommended for the finishing operation, in which case the grinding belts are pressed by means of contact pressure shell members against the rotating bearing location and at the same time a relative oscillation is produced between the grinding belt and the workpiece, in the longitudinal direction. In that case, the contact pressure shell members should embrace the workpiece by at least 120xc2x0 in each case, preferably by up to 180xc2x0, of cooling/lubricating agents to the machining location, although this cannot always be achieved.


The present invention relates generally to motivational development of desirable behavior. More particularly, the present invention relates to a motivational apparatus which allows use of an electronic device only after a predetermined number of tasks have been successfully completed.
Attempts have been made in society to use motivational methods to achieve certain goals. Much of human behavior can be understood as being directed toward specific goals. Incentive motivation is concerned with the way goals influence behavior. One of the most important aspects of this type of motivation is that any goal one seeks can motivate behavior. For example, the goal of obtaining spending money can serve as a strong motivator for performing yard work.
Commonly, parents will require their children to perform tasks or xe2x80x9cchoresxe2x80x9d in order to obtain privileges. The child""s ability to obtain a privilege is typically made contingent on the performance of socially desirable acts, such as cleaning up one""s bedroom, good personal hygiene, being obedient, and being generally respective of others.
In today""s society, many of the privileges enjoyed by children are related to electronic devices, such as watching television, playing computer games, and talking on the telephone with friends. Making these privileges contingent on the performance of certain tasks would provide a strong motivation to perform these tasks, which, over a period of time, can develop socially desirable behavior and an appreciation for delayed gratification.
Accordingly, what is needed is an apparatus which promotes development of desirable behavior by providing a motivational apparatus which allows access to electronic devices only after a predetermined number of tasks have been successfully completed.
It is an object of the present invention to provide an apparatus for controlling use of electronic devices.
It is another object of the present invention to provide a motivational apparatus which allows use of an electronic device only after a predetermined number of tasks have been successfully completed.
It is another object of the present invention to provide a method for using the motivational apparatus.
These and other objects of the invention are accomplished with a motivational apparatus for controlling use of an electronic device, wherein the apparatus comprises means for interconnecting the apparatus between a source of transmission and the electronic device, and means for controlling transfer of transmissions from the transmission source to the electronic device. The transmissions may be electrical power from an AC or DC source, radio or video signals, analog or digital signals, or any other form of energy or information. The controlling means preferably comprises a plurality of electrical switches, a master switch, and a plurality of light-emitting diodes. Each of the electrical switches is preferably operable to open and close an electrical circuit to activate a diode to emit light and to open and close a portion of a master electrical circuit. The master switch, actuation of which is preferably restricted, is operable to open and close a portion of the master electrical circuit. The electrical switches must all be actuated to allow transfer of transmissions from the transmission source to the master switch, which, in turn, must be actuated to close the master circuit and thereby allow transfer of transmissions from the transmission source to the electronic device.
In operation, the apparatus is interconnected between the electronic device and the transmission source. A list of tasks is prepared and associated with the electrical switches such that one task corresponds to one electrical switch. As each task is successfully completed, the electrical switch corresponding to that task is actuated to light up the diode corresponding to that switch. After all of the tasks are completed, a parent or supervisor may confirm satisfactory completion of the tasks and then actuate the master switch to close the master circuit, thereby allowing transfer of transmissions from the transmission source to the electronic device such that the electronic device is operational.
Other features, objects and advantages of the present invention will become apparent from a reading of the following description as well as a study of the appended drawings.


The technological advancement in the last two decades, have allowed for an evolution in the acquisition of goods and/or services, both physical and digital which has facilitated its purchase and delivery, regardless of the geographical location of the buyer user. For example, currently, the acquisition of various electronic goods such as music, videos, films, series and/or television programs, etc., can be done through the purchase of prepaid cards, which are acquired through a point of sale terminal of some establishment, where said prepaid card has a code that allows it the user to access the electronic good in the portal of the corresponding company.
An example of the above can be found in European Patent Application No. EP 1 519 332 A1, which discloses a method and system for providing digital content to consumers using a prepaid digital content medium. The method includes receiving unique identification information associated with the prepaid digital content medium (PDCM) from a PDCM distributor. Once a buyer has acquired a PDCM, the unique identification information associated with said PDCM is sent to an authentication service provider and the PDCM is activated based on said identification information. The authentication service provider sends an activation confirmation of the PDCM to the digital content provider in response to a confirmation request from said digital content provider, wherein the digital content provider sends a confirmation request in response to a request of digital content by a consumer who has acquired the PDCM.
The system above described gives the buyer the possibility to dispose and use the electronic good immediately after the transaction with the digital content provider is completed. In one of its modalities, said system uses prepaid cards that the user acquires in a physical establishment, which constitutes a limitation for the sales of the establishment, since the establishment has a “limited” number of cards to sell and in the case in which they are terminated, the user could not acquire the electronic good in said establishment. Therefore, the establishment must keep in physical stock, the prepaid cards of the digital content provider for sale to the public.
In the state of the art, we can find, in addition to the above prepaid cards, the use of printed codes in a purchase ticket, (known as “pin on receipt”), which is another way in which a user can purchase a code to access digital content from a provider. An example of this is described in U.S. Pat. No. 7,613,237, which comprises a system and method for providing a personal identification number (PIN) printed on a receipt by a customer terminal. The method includes storing at the client terminal, receipt formats that are sent from a server for various prepaid services from a plurality of prepaid service providers. The method further includes receiving, at the client terminal, a request for a PIN associated with one or more of the various prepaid services. The requested PIN and other information associated with one or more of the various prepaid services is displayed or printed according to one or more of the receipt formats for its reception and dispensing by the customer terminal.
The method above described eliminates the use of prepaid cards, which entails that the trade in question is no longer limited to the physical stock of said cards and has “unlimited” availability for the sale of codes to the user.
However, said method is limited to the user moving to the location where the point of sale terminal is located. In addition, there is a risk that the user may damage or misplace the receipt where the PIN is printed, and in case this happens, it is not possible for the user to receive the PIN printed again at the establishment where he acquired it. Another disadvantage of the above described method is that there is a need for a printer, whether thermal, dot matrix, inkjet or laser, whereby the ability to generate sales in the establishments is limited to having a device that allows printing the access code and instructions for use.
The technological advance and the decrease in the costs of physical electronic products such as cell phones and tablets, have allowed its massification in our society, which means that most of the people currently have an equipment and assigned cell phone number. That is why many companies and organizations since a few years began to develop digital systems that allow the sending of notifications to the user cell phone number, which may contain information on an action or a code.
Particularly, some banks have the service of sending the personal identification number (PIN) to their users via SMS type electronic messages, which prevents the user from having to physically move to the branch of the bank to obtain the PIN. With this, the user can promptly have his PIN for activation of a credit or debit card. However, this system is limited to sending these numbers for specific use in the services and products offered by the issuing bank.
Accordingly, in the state of the art, to date there is no efficient system that allows the acquisition of electronic products and/or services by means of a code that is sent to a user device through an electronic message, which allows the user to have immediate access to the product and/or service, when acquired through the server portal of the provider.


The present invention relates to a double acting hydraulic piston and cylinder assembly and a method for assembling the same.
Double acting, double ended cylinders include a piston rod which extends from both ends of the cylinder. The piston operates in both directions by introducing fluid under pressure alternatively to opposite sides of the piston.
In the past, pistons for such double ended cylinders have been fastened to the rod by several different methods. One method comprises threading a two piece rod together within the piston so that the rod extends from opposite ends of the piston. Another method involves welding the piston in place on the rod. A third method involves installing collars on both sides of the piston for holding the piston against axial movement on the rod. A fourth method involves pinning the piston to the rod. Therefore, a primary object of the present invention is the provision of an improved double acting hydraulic piston and cylinder assembly and an improved method for assembling same.
A further object of the present invention is the provision of means for securing the piston to the rod which eliminates the disadvantage of distortion of the rod which occurs in the present method of welding the piston to the rod.
A further object of the present invention is the provision of a device for attaching the piston to the rod so that the piston can be fitted loosely over the rod and then attached securely in place.
A further object of the present invention is the provision of a means for holding the piston positively in place once it is installed so that it will not move in either direction axially on the rod.
A further object of the present invention is the provision of a device which may be disassembled easily for removing the piston and for repacking or rebuilding the cylinder and piston assembly.
A further object of the present invention is the provision of an improved hydraulic piston and cylinder assembly wherein the piston rod is straight and completely concentric since there is only one part to the piston rod rather than the prior method of threading two piston rod segments into the piston.
A further object of the present invention is the provision of a hydraulic piston and cylinder assembly which has interchangeable parts adapted to high production techniques.


During the implantation of an endocardial lead body, the lead is introduced into the heart using a venous approach, usually from the subclavian or cephalic vein in the shoulder area under the pectoral muscle. To stabilize the lead body at the venous entry site, the lead body is secured to both the vein and to the surrounding fascia tissue. A suture placed around the vein near the lead entry point ties the lead body to the vein, and a suture sleeve around the lead body is used to anchor the lead body to adjacent tissue.
Suture sleeves in present use are generally tubular structures molded out of a soft, implantable elastomer such as silicone. After the lead body is tied to the vein, the sleeve is slid along the lead body to the location at which the lead is to be anchored to the underlying tissue. One or more sutures are then tied around the sleeve to compress it and thereby secure it to the lead body. Circumferential grooves in the outer surface of the sleeve are typically provided for this purpose. The last step is to anchor the sleeve to adjacent body tissue; sutures passed through eyelets formed in a pair of tabs projecting from the sleeve provide the required anchoring.
These existing suture sleeves have several drawbacks. For example, it is difficult for the physician to control the degree to which these sleeves are compressed when they are secured to the lead body. The ligature around the sleeve must be tight enough to prevent the lead body from sliding in the suture sleeve but not so tight as to damage the insulation of the lead body. This is especially important with bipolar coaxial leads because an excessively tight ligature could rupture the lead insulation and cause the outer and inner electrical leads to come into contact with each other, resulting in a short circuit. Overtightened ligatures can also result in electrical lead fractures. These problems are common enough to warrant the inclusion of cautionary information in pacemaker product literature or in notices included in the product packaging regarding the use of anchoring sleeves. It would therefore be desirable to eliminate the need for sutures for compressing the sleeve.
U.S. Pat. No. 4,672,979 discloses another type of suture sleeve comprising an outer, elastomeric tubular sleeve and a relatively stiff collet member. The collet includes a plurality of axially extending legs having inner surfaces that are serrated so as to firmly grip the lead body. In use, the collet and the tubular sleeve are separately threaded onto the lead body. With the collet positioned at the lead body anchoring site, the tubular sleeve is forced over the collet thereby urging the serrated surfaces of the collet inwardly into engagement with the lead body. The assembly is then sutured to surrounding tissue to anchor the lead body.
The suture sleeve of the '979 patent has several disadvantages. The serrations have a tendency to pinch and puncture the outer insulative layer of the lead body. Moreover, because the tubular sleeve and collet are separate elements, during positioning of the collet the tubular sleeve may slide down the lead body due to its lubricity when covered with body fluids. In this event, the suture sleeve installation is substantially complicated.
Accordingly, it is an object of the present invention to provide a suture sleeve for securely gripping and anchoring the lead body of an implantable medical device, such as a cardiac pacemaker, that does not require the use of sutures to compress the sleeve.
It is another object of the present invention to provide a lead body gripping and anchoring suture sleeve that does not damage the lead body.
It is yet another object of the present invention to provide a compressible lead body gripping and anchoring suture sleeve in which the compression of the sleeve is self-limiting so as to prevent lead body damage.


Many satellites and other systems have one or more covers or doors to protect internal mechanisms, e.g., optics, sensors and sensitive machinery during transport or other periods of disuse. These types of doors utilize various mechanisms, such as mechanical launch locks to hold them in a closed position and motors to open them. Motors and the control circuitry by which they are operated are expensive to design, procure, manufacture and test. In some applications, such as space-based systems, testing typically includes a life cycle test which could take months to complete. Additional items that drive cost in such space-based systems include the launch lock, the control/telemetry electronics, the drive motor, the gear box, as well as vacuum compatible bearings and grease. Research and development efforts that seek to simplify cover/door mechanisms, and to reduce cost accordingly, are ongoing.


Thermoelectric heat transfer systems are well known for use in refrigeration. A typical thermoelectric heat transfer system includes at least one thermoelectric module to create a temperature differential. More specifically, when energized, heat moves across the thermoelectric module to form a hot surface and a cold surface. The cold surface provides the cooling needed for refrigeration.
In recent years, improvements have been made to utilize coolant circuits to draw heat off of the hot surface of the thermoelectric module to further improve the efficiency of refrigeration. Referring to U.S. Pat. No. 5,653,111 to Attey et al., a thermoelectric heat transfer system utilizing a coolant circuit for this purpose is shown. In Attey et al., the thermoelectric heat transfer system includes a pump in fluid communication with the coolant circuit to circulate coolant. A first heat exchanger is disposed in fluid communication with the coolant circuit to remove heat from the coolant being circulated. At the same time, a manifold is in fluid communication with the coolant circuit. An outer surface of the manifold is in contact with a hot surface of a thermoelectric module. By thermally connecting the coolant circuit with the hot surface of the thermoelectric module, the coolant can draw heat from the hot surface to improve the cooling efficiency of the thermoelectric module. The cold surface of the thermoelectric module is in contact with an outer surface of a second manifold to cool fluid flowing through the second manifold.
Thermoelectric heat transfer systems for cooling beverage containers are also well known in the art. A typical heat transfer system for cooling a beverage container includes a sleeve adapted to receive the beverage container. In these systems, the thermoelectric module is disposed within the sleeve to create a temperature differential between the sleeve and the beverage container. More specifically, a hot surface of the thermoelectric module is in contact with the sleeve, while a cold surface of the thermoelectric module is in contact with the beverage container thereby drawing heat from the beverage container. A fan assembly draws heat away from the sleeve. An example of such a system is shown in U.S. Pat. No. 6,530,232 to Kitchens.


1. Field of the Invention
The present invention relates to a selective catalytic process for preparing N-halothiosulfonamide modified terpolymers of ethylene-alpha olefin-diene, and catalyst compositions suitable for use in this process.
2. Description of Information Disclosures
Modified polymers of the type of interest herein, specifically rubbery polymers, are described in U.S. Pat. No. 3,915,907 and U.S. Pat. No. 3,970,133 (R. J. Hopper) incorporated herein by reference. The desirability and advantages of such polymers was additionally disclosed in articles authored and co-authored by R. J. Hopper (Rubber Chemistry and Technology, Vol. 49, p. 341-352 (1976) and International Conference on Advances in the Stabilization and Controlled Degradation of Polymers, Lucerne, Switzerland, May 23-25, 1984).
These references describe the reaction of various N-chlorothioamides, and particularly N-chlorothio-sufonamides with various ethylene propylene diene monomer (EPDM) rubbers in solutions (see, e.g., Examples I-XII of U.S. Pat. No. 3,915,907) as well as by mixing in a Banbury.RTM. type internal mixer (Examples XIII-XVI of U.S. Pat. No. 3,915,907). Furthermore, in Example XVII of the same reference, there is disclosed in a solution reaction the use of powdered anhydrous zinc chloride (this is referred to as a catalyst in Table I, footnote g and page 346 of the cited Rubber Chemistry and Technology article). The references contain no further disclosure concerning the effect of zinc chloride nor do they suggest the use of other catalytic agents.
U.S. Pat. No. 4,820,780 issued Apr. 11, 1989 discloses a method of preparing a N-chlorothiosulfonamide-modified terpolymer of ethylene, alpha olefin containing from 3 to 6 carbon atoms and a diene in the presence of a saturated aliphatic carboxylic acid containing from 6 to 30 carbon atoms, such as stearic acid. Calcium carbonate may also be added to the reaction as a scavenger for the HCl by-product. It does not suggest the use of metal salts of weak acids as catalysts.
It would be desirable to improve the rate of reaction, the conversion and product quality produced by known processes to achieve commercially useful conditions. It would be particularly useful to improve the melt phase process so as to enhance the addition reaction while minimizing the crosslinking reaction.
It has now been found that certain catalyst compositions comprising zinc salts or iron salts of weak acid in combination with a metal salt of certain metals (other than zinc or iron) of weak acids (i.e., co-catalyst) are selective catalysts in the preparation of N-halothiosulfonamide modified terpolymers of ethylene-alpha olefin-diene. By "selectively," it is intended herein that the desired addition reaction is increased while the undesired crosslinking reaction, which leads to increased Mooney viscosity and to gelation, is minimized.
Mixtures of blends of low-unsaturation rubbery polymers, particularly EPDM, with highly unsaturated rubbery polymers are of practical importance because of the superior ozone resistance imparted to the blend by the low-unsaturation EPDM rubber. Unfortunately, the presence of the low-unsaturation rubber also affects the mechanical and hysteresis characteristics of the vulcanizates in an adverse manner, as evidenced by lower tensile strength and modulus values, and by higher dynamic heat build-up and permanent set. These undesirable responses are contributed to by the mutual incompatibility of the two types of rubber, the substantially slower cure rate of the low-unsaturation rubber, and the greater affinity of the typically polar curvatures for the high-unsaturation rubber. As a result, the vulcanized blend is a heterogeneous dispersion of poorly cured and/or largely uncured low-unsaturation rubber in well cured high-unsaturation rubber. The resulting poorer mechanical and hysteresis properties severely limit, or preclude, the use of such blends in articles subjected to severe service requirements such as tires. A method for improving the physical and dynamic properties of such rubbery polymer vulcanized blends is of considerable commercial and practical importance.


Multiuser diversity is one of diversities caused by independently time-varying a channel environment between users in a wireless communication system. Multiuser diversity gain is obtained by allocating a resource when a channel of each user reaches the best condition through scheduling during observation of a change of a channel of each user. As the change of the channel is increased, the diversity gain is increased. Accordingly, the diversity gain is limited under a channel environment where the change of the channel is small or slow. Under the above-mentioned environment, the diversity gain is generated by inducing a large and quick change of the channel using multiple transmission antennas. This method is called opportunistic beamforming (hereinafter referred to as “OBF”) or random beamforming.
OBF technology is limited to the diversity thereof under an environment corresponding to a small number of users, since it uses only one beam to search an optimal user at each time slot. Therefore, technologies that generate multibeams and select an optimal beam of each user to increase multiuser diversity gain, have been proposed in order to overcome the above-mentioned limitation. As these technologies in the related art, there are codebook-based opportunistic beamforming (hereinafter referred to as “COBF”) and codebook-based beamforming with code rotation (hereinafter referred to as “CBF-CR”), where the codebook contains multiple vectors used for multibeams.
The COBF uses a pilot only for channel estimation, and allows each user to estimate a channel. A base station receives from each user the maximum beam index and channel quality information (hereinafter referred to as “CQI”) corresponding to the beam, as feedback. Then, the base station performs scheduling by allocating a user having the maximum gain to each beam thereof, and transmits data. In the COBF method, a unitary matrix varying with time is multiplied by one of beam vectors in codebook, so that a beam varying with time is obtained. The COBF has a merit in that a pilot is fixed to a pilot used for channel estimation and a selective diversity effect is thus increased to infinity.
The CBF-CR generates multiple codebooks by grouping large-sized codebooks and then obtains multiple beams that vary with time by diversely using the codebooks with change of time. Therefore, the same effect as the COBF method is obtained in the CBF-CR.
In the COBF, multibeams have been obtained by multiplying unitary matrices, which vary with time, by beam vectors of one codebook. In contrast, in the CBF-CR, multibeams are obtained by generating multiple codebooks, and then using the codebook while exchanging the codebook with time.
However, the method of designing a beam and the method of designing a beam parameter in the related art have a problem in that performance deteriorates.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.


1. Field of the Invention
The invention relates to a decoding apparatus, more particularly to a Context-based Adaptive Binary Arithmetic Coding (CABAC) decoding apparatus and a decoding method thereof.
2. Description of the Related Art
H.264/AVC is a recently developed video signal compression standard, which employs advanced encoding techniques to provide superior compression efficiency compared to other existing video signal compression standards such as MPEG-1, MPEG-2, H.263, etc.
H.264/AVC adopts Context-based Adaptive Variable Length Coding (CAVLC) technology or CABAC technology for entropy encoding to increase the coding efficiency. While the coding efficiency of CABAC technology is about 10% higher than that of CAVLC technology, encoding/decoding calculations in CABAC are more complex than those in CAVLC. During the CABAC decoding process, an input bit stream must at least go through an initialization step and an arithmetic decoding step before the decoding procedure can be completed. The total amount of time required by the initialization step and the arithmetic decoding step, which is actually relatively long, has a critical affect on the efficiency of a decoding system. As such, it is highly desired to reduce latency during the CABAC decoding process so as to improve the overall efficiency of the decoding system.


Circular extrusion dies with inner and outer lips are usually adjusted for concentricity by a circle of bolts located radially around the outer die lip. Concentricity adjustment is necessary to achieve a consistent transverse thickness of the material leaving the die. In most cases, the adjusting bolts move the complete outer lip to obtain concentricity with the inner lip. A compromise is needed due to temperature and machining variations around the two lips. Where a higher degree of control is desired, a flexible outer lip may be used. The adjusting bolts push on segmented shoes which flex a small sector of the outer lip. This forces the lip into the desired shape to achieve uniform thickness of material. Heated expansion bolts are a further sophistication allowing a finer, remote controlled adjustment. Flexible lip dies suffer from a number of deficiencies, such as undesired distortion of areas adjacent to the sector being flexed by an adjusting bolt, requirement for large forces to flex the lips making repeatability and fine adjustment difficult, necessity for construction of a very thin flex lip which is then susceptible to machining distortion and damage, and complications in heat transfer to and from the outer die lip due to thin construction and intimate contact with the segmented shoes around the periphery.
Hahn, et al., U.S. Pat. No. 4,548,570, describes an extrusion apparatus for producing thermoplastic pipe. Adjustment of the thickness of the pipe is achieved by varying the heat to heater cartridges which causes thermoplastic material in proximity to the heated section of sleeve to become less viscous and to flow at a faster rate. This increases the amount of thermoplastic material at that location, compared with lesser heated sections of the extrusion passageway. Additionally, radial repositioning of the sleeve due to expansion of the heater bolts will increase the width of the arcuate portion of the melt passageway in proximity to the heated section of the sleeve, causing increased thickness of the thermoplastic material. This heating operation does not appear to take place at the die lips. Phipps, U.S. Pat. No. 4,201,534 describes a foam extrusion die assembly which is adjusted by means of screws in the area of the die lips. Yazaki, et al., U.S. Pat. No. 4,057,385, describes cooling a deckle so as to increase the viscosity of the molten resin around the deckle, to prevent leakage. Solop, U.S. Pat. No. 3,984,508, also describes a method of controlling an extrudate using a deckle bar having heating and cooling means. Porter, et al., U.S. Pat. No. 3,973,890, describes adjusting relative positions of the die plates to maintain a constant pressure of heat plastified material. The temperature of the pellet cutting head can be heated or cooled by circulating fluids.


In this century, the shortage of fresh water will surpass the shortage of energy as a global concern for humanity; and these two challenges are inexorably linked, as explained, for example, in the “Special Report on Water” in the 20 May 2010 issue of The Economist. Fresh water is one of the most fundamental needs of humans and other organisms; each human needs to consume a minimum of about two liters per day. The world also faces greater freshwater demands from farming and industrial processes.
The hazards posed by insufficient water supplies are particularly acute. A shortage of fresh water may lead to a variety of crises, including famine, disease, death, forced mass migration, cross-region conflict/war, and collapsed ecosystems. Despite the criticality of the need for fresh water and the profound consequences of shortages, supplies of fresh water are particularly constrained. 97.5% of the water on Earth is salty, and about 70% of the remainder is locked up as ice (mostly in ice caps and glaciers), leaving only a fraction of all water on Earth as available fresh (non-saline) water.
Moreover, the earth's water that is fresh and available is not evenly distributed. For example, heavily populated countries, such as India and China, have many regions that are subject to scarce supplies. Further still, the supply of fresh water is often seasonally inconsistent. Meanwhile, demands for fresh water are tightening across the globe. Reservoirs are drying up; aquifers are falling; rivers are dying; and glaciers and ice caps are retracting. Rising populations increase demand, as do shifts in farming and increased industrialization. Climate change poses even more threats in many regions. Consequently, the number of people facing water shortages is increasing. Naturally occurring fresh water, however, is typically confined to regional drainage basins; and transport of water is expensive and energy-intensive.
Additionally, water can be advantageously extracted from contaminated waste streams (e.g., from oil and gas production) both to produce fresh water and to concentrate and reduce the volume of the waste streams, thereby reducing pollution and contamination and reducing costs.
Nevertheless, many of the existing processes for producing fresh water from seawater (or from brackish water or contaminated waste streams) require massive amounts of energy. Reverse osmosis (RO) is currently the leading desalination technology. In large-scale plants, the specific electricity required can be as low as 4 kWh/m3 at 30% recovery, compared to the theoretical minimum of around 1 kWh/m3; smaller-scale RO systems (e.g., aboard ships) are less efficient.
Other existing seawater desalination systems include thermal-energy-based multi-stage flash (MSF) distillation, and multi-effect distillation (MED), both of which are energy- and capital-intensive processes. In MSF and MED systems, however, the maximum brine temperature and the maximum temperature of the heat input are limited in order to avoid calcium sulfate, magnesium hydroxide and calcium carbonate precipitation, which leads to the formation of soft and hard scale on the heat transfer equipment.
Humidification-dehumidification (HDH) desalination systems include a humidifier and a condenser as their main components and use a carrier gas (e.g., air) to desalinate brine streams. A simple version of this technology includes a humidifier, a condenser, and a heater to heat the brine stream. In the humidifier, hot brine comes in direct contact with dry air, and this air becomes heated and humidified. In the condenser, the heated and humidified air is brought into (indirect) contact with a coolant (for example, cold brine) and gets dehumidified, producing pure water and dehumidified air. The HDH process operates at lower top brine temperatures than MSF and MED systems, precipitation of scaling components is hence avoided to some extent.
Another approach, described in U.S. Pat. No. 8,119,007 B2 (A. Bajpayee, et al.), uses directional solvent that directionally dissolves water but does not dissolve salt. The directional solvent is heated to dissolve water from a salt solution into the directional solvent. The remaining highly concentrated salt water is removed, and the solution of directional solvent and water is cooled to precipitate substantially pure water out of the solution.
The present inventor was also named as one of the inventors on the following patent applications that include additional discussion of HDH and other processes for purifying water: U.S. application Ser. No. 12/554,726, filed 4 Sep. 2009; U.S. application Ser. No. 12/573,221, filed 5 Oct. 2009; U.S. application Ser. No. 13/028,170, filed 15 Feb. 2011; and U.S. application Ser. No. 13/241,907, filed 23 Sep. 2011; U.S. application Ser. No. 13/550,094, filed 16 Jul. 2012; U.S. application Ser. No. 13/916,038, filed 12 Jun. 2013; and U.S. application Ser. No. 13/958,968, filed 5 Aug. 2013.


The present invention relates to a process for manufacturing bodies of polymeric material by means of the blow-molding technique, in particular to provide bodies comprising a core of foamed material enclosed by an external shell.
Such bodies normally display a rigid structure and good properties of heat insulation, so to make the use thereof for such household electrical appliances, as refrigerators, and the like, particularly advantageous. At present, the technique of blow-molding is used in order to manufacture a hollow shell of thermoplastic material, inside which a thermosetting foam is subsequently injected, for example a polyurethane foam obtained by means of the well-known RIM technology. Such an operating way shows problems both in terms of possibility of finished article recycling, and in terms of environmental pollution by the foaming agent.
In fact, the chemical nature of the foamed polyurethanic core makes it impossible for the manufactured article to be recycled, and the chloro-fluoro-alkane foaming agent normally used in RIM technology causes problems of interaction with ozone in the stratosphere. Furthermore, the execution of the process according to the two-step technology known from the prior art (blow-molding and subsequent foam injection) causes the production cycle to be rather slow and expensive.
The purpose of the present invention is of supplying a process of the type as specified in the introduction to the specification, which does not display these drawbacks and which is simple and inexpensive to carry out.
According to the invention, such a purpose is achieved because the blowing is performed by introducing into the interior of a hollow thermoplastic body a foamable thermoplastic polymeric material suitable for bringing the walls of the hollow body into contact with the walls of a mold.
By "foamable thermoplastic polymeric material" any thermoplastic material mixed with a foaming agent, e.g., CO.sub.2, N.sub.2, hydrocarbons, are meant. It is evident that, as in the traditional blow-molding technology, the hollow extruded body (parison) is at a temperature close to the polymer softening temperature, and anyway such as to secure the "blowing" of the hollow body. This feature is particularly advantageous in the case of the present invention, because the foamed thermoplastic material (which also is at a temperature which is close to the polymer softening temperature) can be thermowelded to the walls of the hollow body, thus making it possible to obtain a structurally resistant manufactured article. A further advantage of the present invention relates to the possibility of using the same polymeric material, or materials belonging to the same polymeric family, for both the foamed core and the external shell, making it possible for the manufactured article to be recycled at the end of its useful life time. The process according to the present invention also makes it possible for the production cycle to be speeded up, as compared to the traditional technology of blow-molding and subsequent foaming of the cooled hollow shell.
A further purpose of the present invention is providing a device for carrying out the above said process.
Such a device, of the type which comprises an extruder with an accumulation chamber suitable for cyclically extruding a tubular parison between two mobile half-molds, is characterized in that said device also comprises a second extruder for a polymeric material admixed with a foaming agent, and an auxiliary accumulation chamber in communication with said second extruder, and equipped with an injection nozzle centrally installed relative to a ring-shaped nozzle for the tubular parison extrusion.
Further advantages and characteristics of the process and device according to the invention will be clear from the following disclosure in detail, supplied for merely exemplifying, non-limitative, purposes, by referring to the accompanying drawings, in which:


Air intake passages for automobile heating and air conditioning systems have been known since the advent of climate control systems for passenger compartments of automobiles. With the growing popularity of vans and other vehicles with larger-than-standard passenger compartments, there is an increased need to provide climate control systems which will efficiently control the climate in the larger passenger compartment.
While it has been known that a larger air flow through a climate control system will increase the efficiency and rate at which a system can process, and thus control, the volume of air in the passenger compartment, attempts to increase the air flow into climate control systems have had limited success. The application of the principle of achieving a more efficient heat exchange by increasing the air flow to practical use for a motor vehicle passenger climate control system has not been an easy matter. In large part, this is because the spatial constraints of the application do not lend themselves to simply increasing the cross-section of the intake passage.
Other prior art approaches to increasing air flow have included providing additional entries into the intake passage of the vehicle climate control system. For example, Japanese Patent 58-101813 to Yamashita provides a second door 17 to an inlet 18, which door is interlocked to a door 2 of another intake 1. This approach merely provides two doors in the same plane of the housing wall, requiring a larger cross-sectional area to be available in that plane.
In contrast, U.S. Pat. No. 4,802,405 discloses three free-circulated air openings in three different walls of its system casing, but each inlet requires control by a separate damper door. U.S. Pat. No. 4,779,672 similarly discloses a system having two recirculation air inlets, each of which is provided with its own damper door, with corresponding control mechanisms.
French Patent 2,556,289 discloses a mixer box for a vehicle interior heater which provides for selective mix of partial recirculation air which comes entirely from window openings provided in a single wall.
U.S. Pat. No. 4,676,272 generally exemplifies an air flow control passage also not dedicated to the problem of increasing air flow of recirculated air into a vehicle climate control system. Similarly, the system of German Patent 3,421,323 discloses an air distributor which does not address increasing air flow of recirculation air into a system by multiple entries in different walls of the casing.
As will be seen below, the multiple entry air intake passage of the present invention provides a simplified design for increasing air flow while simultaneously eliminating the need for extra doors and door actuating mechanisms, in turn providing savings in cost and size.


1. Field Of The Invention
This invention relates to computer systems and, more particularly, to methods and apparatus for automatically connecting computers to one of two available local area networks (LANs).
2. History Of The Prior Art
One of the significant movements in the computer industry has been toward interconnectivity of individual computers by local area networks. Initially, the desire was to allow the sharing of underused assets such as printers. More recently, the impetus has been the desire to share application programs and data and to enhance communication.
Whatever the reasons for their existence, LANs are proliferating. Typically, a LAN will be installed initially to provide connection between a small group of local computer users. The first LANs which were installed utilized coaxial cable as the physical wiring for the transmission of signals. Coaxial cable was necessary in order to reduce the noise and allow operation in the face of signal attenuation. As technology advanced and standards changed, it became possible to utilize twisted pair wiring as the physical connection to join the computers of a LAN together. Twisted pair wiring is preferred because it is less expensive and less expensive to install.
Often it is desirable to change computers from a coaxial network to a twisted pair network. During some interim period, it may be desirable to connect the computers to both networks. In a similar manner, it may become desirable to connect computers already joined in a local twisted pair network to another network in which the computers are joined by coaxial cable. In either case, it is possible that a number of individual computers will be physically connected simultaneously to two separate networks, a twisted pair network and a coaxial cable network. It is desirable that these computers be able to utilize either one of the two networks which is available and functioning so that if one network is not functioning communications will automatically be established on the other network.


Digital content distribution is extremely popular. Most content producers desire some sort of rights management, and so content distribution systems typically include content management systems that control aspects of playback, copying, or other usage of the digital content. As one example, a device in the content distribution chain may be configured to enforce terms of a license provided by a content producer or other authority. The license is stored as one or more computer-accessible files or other data structures accessed by the device to enable (or deny) access or other use of the content.


As consumer devices have gotten smaller and smaller in response to consumer demand, the individual components of these devices have necessarily decreased in size as well. Semiconductor devices, which make up a major component of devices such as mobile phones, computer tablets, and the like, have been pressured to become smaller and smaller, with a corresponding pressure on the individual devices (e.g., transistors, resistors, capacitors, etc.) within the semiconductor devices to also be reduced in size.
One enabling technology that is used in the manufacturing processes of semiconductor devices is the use of photolithographic materials. Such materials are applied to a surface and then exposed to an energy that has itself been patterned. Such an exposure modifies the chemical and physical properties of the exposed regions of the photolithographic material. This modification, along with the lack of modification in regions of the photolithographic material that were not exposed, can be exploited to remove one region without removing the other.
However, as the size of individual devices has decreased, process windows for photolithographic processing as become tighter and tighter. As such, advances in the field of photolithographic processing have been necessitated in order to keep up the ability to scale down the devices, and further improvements are needed in order to meet the desired design criteria such that the march towards smaller and smaller components may be maintained.
Corresponding numerals and symbols in the different figures generally refer to corresponding parts unless otherwise indicated. The figures are drawn to clearly illustrate the relevant aspects of the embodiments and are not necessarily drawn to scale.


The present invention relates to the field of integrated circuit devices. More specifically, it relates to testing and sorting individual integrated circuit devices according to their operational characteristics.
Integrated circuit devices, or dies, are manufactured through a multi-step process during which transistors and other electronic circuit components are formed in areas on a thin silicon wafer. After the circuit fabrication is completed, the individual dies are cut from the silicon wafer.
The manufacturing process for integrated circuits is imprecise; minor variations during each step of the manufacturing process affect vital performance characteristics of individual dies. These variations impact the speed at which a particular die operates, which directly impacts the commercial value of each individual die. It is therefore desirable to the manufacturer to determine the speed at which individual dies can operate so the manufacturer can then sort them accordingly.
Typical integrated circuit test devices consist of bench setups utilizing standard lab equipment including an oscilloscope or frequency meter to directly or indirectly measure the operating frequency (speed) of the circuit. In some setups such outboard test equipment is used to test the speed of a device, such as an oscillator, which is fabricated in association with a die but which is not materially part of the operational die circuit. The tested frequency of the oscillator is representative of the operational speed of the die. All these systems, however, require expensive specialized and sometimes bulky frequency measurement equipment to be provided with the test setup.
What is needed is a simplified method and apparatus for determining the operating speed of the die.
The present invention provides a method and apparatus for characterizing an integrated circuit device based on device switching speed on an individual die or lot-by-lot basis by measuring frequency in a digital domain. An oscillator, integrated in association with the die and capable of generating pulses, and a counter are used during a test period to count the pulses from the oscillator to a predetermined value. A pulse generator is initiated at the beginning of a test which resets the counter to a known state and starts the oscillator. When the counter reaches its predetermined maximum count value a signal is issued. The elapsed time between the initiation of the oscillator and when the counter full signal is issued represents the summation of many oscillator periods. The period of the oscillator may then be determined by the formula: oscillator period=elapsed time/capacity of counter. The determined oscillator period provides an indication of the operating speed of electronic devices on the die. A digital tester which performs other tests on the die can be used to record the elapsed time and thereby determine the operating speed of a die.
These and other features of the invention will be more clearly understood from the following detailed description of the invention which is provided in connection with the accompanying drawing.


The present invention relates to firearms.
In particular, the present invention relates to that type of firearm, such as a semi-automatic shotgun, which has a bolt capable of moving axially between a forward firing position and a rear retracted position as well as capable of rotating between locked and unlocked positions. Such a bolt, which forms part of the action of the firearm, is housed within a receiver which is formed with an ejection port through which a cartridge case of a spent cartridge is ejected. The movement of the bolt is brought about at least partially by way of a sleeve which surrounds the bolt, and in addition to its other functions, this sleeve serves to close the ejection port when the bolt is in its forward firing position.
Because the ejection port is relatively long and because it must be covered by this sleeve, the sleeve also is undesirably long, and in addition the receiver must be made of a length sufficiently great to receive the relatively long sleeve when the bolt is retracted in order to uncover the ejection port at least to an extent sufficient to permit the cartridge case to be ejected.
Thus, these factors result in an undesirably long action and receiver.


The present invention relates to a method for analyzing a stereoscopic image of a fundus to detect and analyze the optic disk on the basis of the stereoscopic image of the fundus, and an apparatus for executing that method.
Glaucoma is known as a disease of the visual function. In the examination of glaucoma, it is said that the observation of patient's optic disk on the basis of an image of the fundus is important. In recent years, it has become possible to quantitatively measure the optic disk due to progress in the technology of image analysis. As the results of analysis, the following parameters are computed: the C/D ratio (a distance ratio between a rim of an optic disk cupping (the optic disk cupping being referred to as a cup) and a rim of the optic disk (the optic disk being referred to as a disk)), the area of the plane within the cup rim, the depth of the cup, the volume of the cup, and the like.
The rim of the cup which serves as a basis for the computation of these parameters is conventionally detected such that, by using the disk as a reference, positions which are lowered by an arbitrary depth (e.g., 150 .mu.m) from the disk are estimated to plot the rim of the cup.
However, since it is not uncommon that overall disk regions of the patent's eyes are inclined, there arise cases where the rim of the cup cannot be detected by the above-described detection method.
It is possible to obviate the above-described problem if an operator designates three points on the disk region and effects analysis by using as a reference plane an inclined plane thus determined. In accordance with this method, however, there is a problem in that the data of the cups detected vary for each operator, and the data can be different on each occasion of analysis even for the same operator, with the result that the reliability and reproducibility of the results of analysis are poor.


Non-volatile semiconductor memories (NVSMs) are widely used in many electronic devices such as personal digital assistants (PDAs), laptop computers, mobile phones and digital cameras. Some of these memories have arrays of charge storage transistors, such as floating gate transistors.


This invention relates to a blood collection assembly incorporating a microcollection container, and is related to the subject matter disclosed in co-pending application Ser. No. 695,121, filed Jan. 28, 1985. The invention is an improvement over the collection assembly described and claimed in U.S. Pat. No. 4,397,318, issued Aug. 9, 1983, which is hereby incorporated by reference in its entirety. Reference should be made to that patent for background information concerning the teachings of the invention here. The earlier patent involved the use of a scoop collector for connection to a blood microcollection container for engaging a puncture wound to obtain a blood sample from an individual for subsequent examination of that sample for the determination of the presence or absence of some disease or other problem in a patient. The scoop-type blood collection device provides a substantially larger engaging surface for engaging the puncture for collecting the blood, and a substantially larger transfer surface for rapidly transferring the blood from the collector into the microcollection container. Because of the relatively large engaging surface for engaging the puncture wound, the arrangement does not require a precise positioning of the scoop engaging surface in order to initiate and rapidly transfer a quantity of blood to the microcollection container.
As will be appreciated by practitioners-in-the-art, recent advancements in analytical instrumentation have made it possible to carry out a variety of hematological or chemical diagnostic procedures on very small quantities of blood. Because of this, a patient's heel, finger or earlobe may be punctured and a very small quantity of blood rapidly collected into a microcollection container for such testing. Such arrangements obviate the need to withdraw venous blood from patients. However, such collection arrangements must be such that the blood is rapidly collected prior to any coagulation thereof. In the past, prior to the scoop collector disclosed in the above-noted U.S. Pat. No. 4,397,318, a cap or top arrangement was configured to fit on the top of a microcollection container with the top having an integral capillary tube for engaging the puncture and transferring blood to the container. However, with such an arrangement, the tip of the capillary tube had to be arranged precisely adjacent the puncture wound and the entire apparatus had to be so positioned that the blood flow along the bottom surface of the tubular microcollection container moved continuously in order to engage the surface of the container. Otherwise, if a precise positioning was not carried out, capillary action was not initiated or was slowed with subsequent clotting. Representative such collectors are taught in U.S. Pat. No. 4,024,857, issued May 24, 1977.
One problem with the scoop collector taught and claimed in U.S. Pat. No. 4,397,318, although the arrangement taught therein is highly efficient for the rapid collection of a blood sample into a microcollection container, is the fact that the assembly for making the collection must be distributed with the microcollection container or tube having a separate cap. Typically, the technician must remove the cap, and place on the container the scoop collector prior to making a collection of a blood sample. Subsequent to this collection, moreover, the scoop collector must then be removed, and the cap replaced on the container for delivery to a lab for investigation of the sample. Such removal and replacement of parts on the top of the blood microcollection container is cumbersome, as one will understand, particularly if the technician is, for example, attempting to take a blood sample from a screaming, wiggly baby. Moreover, the technician or nurse or doctor may become exposed to the blood sample during this transfer procedure in removing the blood collection scoop arrangeent and replacing the cap on the blood microcollection container.
With the invention claimed in the above-noted co-pending application Ser. No. 695,121, by contrast, a scoop arrangement is incorporated into a blood microcollection assembly in such a way that the scoop collector does not have to be removed until such time as the technician in the laboratory wishes to obtain access to the sample in the blood microcollection container. This is achieved by the use of a cap which is a two-position cap. That is, the assembly is distributed to potential users with the cap in place over the scoop collector on the top of the blood microcollection container.
When the nurse or doctor wishes to take a blood sample, the cap is removed and the front end of the scoop collector is placed adacent the wound for collection of blood. Once the blood sample has been taken, the cap is again placed over the scoop collector without any removal of the scoop collector, as in the past. Then, the technician merely has to press-fit the cap down over the scoop collector. This press-fit movement has the effect of permanently locking the cap onto the scoop collector. Therefore, access to the blood sample in the container cannot be obtained unless the cap and the scoop collector arrangement are removed simultaneously. For this reason, no one can be exposed to any blood left in or around the scoop collector arrangement after the sample has been taken, and until such time as the sample is to be obtained from the microcollection tube at the lab.
As practitioners-in-the-art will understand, this arrangement reduces the amount of fumbling and movements necessary during the course of taking a blood sample while at the same time reducing the possibility of contamination to the nurse or anyone else present during the taking of the sample.
With the invention claimed in this application, any difficulty engendered in taking a blood sample is further reduced dramatically by providing in the assembly itself a built-in lancet for making the wound for collecting the blood sample. That is, the lancet is positioned in the blood collector of the assembly and covered by the cap of the assembly prior to use. This allows for sterilization of the lancet and preservation of the sterile condition prior to use.
When a sample of blood is to be collected with the combination assembly of the invention, the cap is removed. Then, the nurse or technician has an exposed collector and an exposed lancet simultaneously. The wound is made with the lancet and the sample collection made without the laying down or picking up of separate devices. The technician's hand is in place at the site of the wound for immediate collection.
Once collection of the sample is completed, the cap is again placed over the collector of the assembly, and moved or forced into its second locking position, as described in the above-noted co-pending application. By this capping procedure, not only is the blood collector removed from contaminating anyone coming into contact, but also, in accordance with this invention, the lancet itself is also capped and removed from such exposure. They are, as will be appreciated by a review of the co-pending application, permanently locked under the cap placed over the blood collection assembly.
Other advantages of the invention include the fact that but a single package must be made up and sterilized to achieve collection of a blood sample. Moreover, only this one package must be opened and handled to obtain collection of the sample followed by proper disposal of contaminating objects.
Other objects and advantages of this invention will be apparent from the following description, the accompanying drawings and the appended claims.


Small diameter glass fibers are useful in a variety of applications including acoustical or thermal insulation materials. When these small diameter glass fibers are properly assembled into a lattice or web, commonly called a wool pack, glass fibers which individually lack strength or stiffness can be formed into a product which is quite strong. The glass fiber insulation which is produced is lightweight, highly compressible and resilient. For purposes of this patent specification, in using the terms "glass fibers" and "glass compositions", "glass" is intended to include any of the glassy forms of mineral materials, such as rock, slag and basalt, as well as traditional glasses.
The common prior art methods for producing glass fiber insulation products involve producing glass fibers from a rotary process. A single molten glass composition is forced through the orifices in the outer wall of a centrifuge or spinner, producing primarily straight glass fibers. The fibers are drawn downward by a blower, and conventional air knife and lapping techniques are typically used to disperse the veil. The binder required to bond the fibers into a wool product is sprayed onto the fibers as they are drawn downward. The fibers are then collected and formed into a wool pack. The wool pack is further processed into insulation products by heating in an oven, and mechanically shaping and cutting the wool pack.
Ideally, insulation products of glass fibers would have uniform spacing between fibers assembled in the lattice. Glass fiber insulation is basically a lattice which traps air between the fibers and prevents circulation of air to inhibit heat transfer. As well, the lattice also retards heat transfer by scattering thermal radiation. A more uniform spacing of fibers would maximize scattering and, therefore, have greater insulating capability.
In the production of wool insulating materials of glass fibers, it becomes necessary to use fibers that are relatively short to achieve desirable lattice properties. Known lapping techniques for dispersion of short fibers in a veil have provided acceptable, although not ideal fiber distribution. By contrast, long fibers tend to become entangled with each other, forming ropes or strings. For purposes of this patent specification, in using the terms "short fibers" and "long fibers", the term "short fibers" is intended to include fibers of approximately 2.54 centimeters (approximately 1 inch) and less, and "long fibers" are intended to include fibers longer than approximately 5.08 centimeters (approximately 2 inches).
Long fibers are more prone to entangle than short fibers, due, in part to their different aerodynamic properties, in addition to fiberizer throughput and geometry. Moreover, the longer they are, the more the long fibers tend to entangle. Conventional lapping techniques have failed to eliminate, and rather tend to enhance, formation of ropes and strings in veils of long or semi-continuous fibers. Even when undisturbed, veils of long fibers tend to form ropes and strings as the veil slows in its descent to the collection surface. Despite movement of the collection surface, long glass fibers (as do undisturbed veils of short fibers) tend to pile up into nonuniform packs of fibers, and unmanageable fiber accumulations. These nonuniform packs, characterized in part by roping and string formation, have long prevented significant commercial use of long fibers. The ropes of long fibers produce a commercially undesirable appearance and, more importantly, create deviation from the ideal uniform lattice and reduce the insulating abilities of the glass wool.
However, even short fibers that are straight form only a haphazard lattice, and some of the fibers lie bunched together. As a result, existing glass wool insulating materials continue to have significant non-uniformities in the distribution of fibers within the product. Thus, the ideal uniform lattice structure cannot be achieved.
A further problem presented by use of short straight fibers is the binder material necessarily added to the fibers to provide product integrity. Binder provides bonding at the fiber to fiber intersections in the lattice, but is expensive and has several environmental drawbacks. As most binders include organic compounds, great pains must be taken to process effluent from the production process to ameliorate the negative environmental impact of such compounds. Further, the binder must be cured with an oven, using additional energy and creating additional environmental cleanup costs. While long fibers display fiber to fiber entanglement even without binder, the non-uniformity of the resulting wool packs has long made them commercially undesirable.
Finally, in addition to the properties of uniformity and integrity, it is desirable for wool packs to exhibit recovery from compression. In the shipping and packaging of insulation products, high compressibility is preferred. It is desirable to compress the wool for shipping and then have it recover rapidly and reliably to the desired size. When the product is compressed, the binder holds firm at fiber to fiber intersections while the glass fibers themselves flex. If the stress upon the fiber increases due to excessive compression, the fiber breaks. Thus, current insulation products are limited in the amount of compression possible while still attaining adequate recovery.
Nonetheless, because long fibers are problematic in nearly all respects, commercial wool insulation products of glass fibers have long used only short straight fibers, despite the various drawbacks of short fibers in lattice non-uniformity, need for binder and related environmental concerns, and limited compressibility. Accordingly, the need remains for further improvements in wool insulation products to improve wool pack properties, reduce cost and eliminate environmental concerns.


For a long time roofing membranes were made from organic felts saturated with bituminous materials such as asphalt or modified bitumen. For several years, those membranes have been improved by adding polyester or fiberglass open grids for strength and fiberglass mats for dimensional stability. See, for example, commonly assigned U.S. Pat. Nos. 4,491,617 and 4,539,254.
In this art, it is still generally believed necessary, even with the improved high strength grids, to continue to utilize during manufacture and retain in the final product an organic felt or mat of some kind, such as a polyester mat, to provide adhesion of bitumen to the reinforcing elements, to increase stiffness, to increase bulk, and to provide toughness to resist punctures. In addition, during processing in vats of high temperature bituminous material, such mats hold the grids of the high strength reinforcing elements in place and together inside the bituminous material. For example, without a polyester mat, a high-strength polyester scrim used for reinforcing comes apart in the vat of hot bituminous material during manufacture of the roofing membrane. In addition, high strength grids manufactured without a polyester mat to hold them together have a tendency to "pull-out" from the fiberglass mat and come to the surface of the roofing membrane. This occurs while the membrane is being coated with bituminous material or during the cooling stages. It is desirable, however, that the polyester grid remain embedded inside the bitumen.
As an example, one current reinforcement for roofing membranes comprises a heavy polyester, open-grid scrim (2.67.times.2.67 yarns per inch, 1000 denier, about 2.0 ounces per square yard) laminated to a lightweight polyester mat (0.5 ounce per square yard, about 17 grams per square meter). This polyester grid/mat product is led with a fiberglass mat (3.75 ounces per square yard) through a vat of bituminous material to create a roofing membrane coated on both sides with bituminous material. During processing the polyester grid is sandwiched between the two mats. One purpose of the polyester mat during this processing is to hold the polyester grid yarns against the fiberglass mat. Without such a lightweight polyester mat, the polyester grid, which is held together with a thermoplastic adhesive (without any mechanical fastening at the cross-overs of the grid), would have a tendency to come apart and/or pull out to the surface of the membrane during impregnation with hot bituminous material.
A problem with this roofing membrane, however, is delamination of the top and bottom bituminous layers in the final product. While the porosity of the lightweight polyester mat is high and saturates rapidly, the polyester mat does not allow the bituminous layers on either side of it to adhere to each other to a great degree. One method used to reduce this problem is to go to the extra step of needle-punching holes in such mats to promote saturation and adhesion, but this added manufacturing step requires additional expense.
Accordingly, a need exists to overcome the above noted drawbacks and produce better and more economical products.


The increasing use of cellular telephones and other communication devices in recent years has made the enforcement of federal regulations on their airborne use difficult. Unauthorized use of cellular devices on aircraft poses a risk, for example, of electromagnetic interference (EMI) to the communication components of commercial and cargo aircraft. With the widespread use of cell phones and other communication devices on board aircraft, and the difficulty of enforcing regulations restricting such use, it would be beneficial to automate compliance with the applicable regulations. Automating compliance with the applicable regulations would also aid in power conservation of the devices when they are airborne.