Radial piston with lubricated piston to shoe swivel joint - has cylinder with curved end faces on shoe inside piston cross-bore

摘要

The piston is for a radial piston unit and is connected to a piston shoe (61) via a swivel joint consisting of a cylindrical portion (1) on the shoe contained in a cross-bore in the piston, with a chamber (53) for pressurised lubricant between them. The end faces (101) of the portion are curved with a radius (5) which is a little shorter than the radius (55) of the piston. The chamber is preferably shaped to form curved sealing faces parallel to the outer wall. The portion may be located in the piston via a linking element. The link may contain a spring to hold piston and piston shoe together.