  K 4-47 is an unusual planetary nebula composed of a compact high-ionization
core and a pair of low-ionization knots. Long-slit medium-resolution spectra of
the knots and core are analyzed in this paper. Assuming photoionization from
the central star, we have derived physical parameters for all the nebular
components, and the (icf) chemical abundances of the core, which appear similar
to Type-I PNe for He and N/O but significantly deficient in oxygen. The nebula
has been further modelled using both photoionization (CLOUDY) and shock
(MAPPINGS) codes. From the photoionization modelling of the core, we find that
both the strong auroral [O III] 4363A and [N II] 5755A emission lines observed
and the optical size of the core cannot be accounted for if a homogeneus
density is adopted. We suggest that a strong density stratification, matching
the high-density core detected at radio wavelengths and the much lower density
of the optical core, might solve the problem. From the bow-shock modelling of
the knots, on the other hand, we find that knots' chemistry is also represented
by Type-I PN abundances, and that they would move with velocities of 250 - 300
km/s.
