Repeat the process for the trailing shoe. Remember to draw the lining mu line towards the abutment not the cylinder. The overall brake factor is the sum of the two shoe factors.
<< Back to Drum Brakes
(FREDERICK ALBERT) STEPNEY ACRES proposed a graphical method for drum brake design whilst working for Vauxhall Motors in 1946. It quickly allows the centre of pressure and brake factor to be calculated and being graphical gives a visual perspective to what's happening.
Drawing Acres Geometry
To see how to construct Acres Geometry, click on each step in turn.
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