摘要 |
The piston mechanism comprises a piston (3), a sliding shoe (6) and a coupling member (18) holding together the piston (3) and sliding shoe (6). The coupling member (18) comprises a shaft part (19) and joint heads (20,21) arranged at the end of the shaft part (19). The heads (20,21) have spherical zone-shaped sliding surfaces (9,11,23,24), which cooperate with corresponding sliding surfaces (9,24) in sliding shoe (6) or in the bottom of the piston (3). Due to the fact that the radius of curvature (R1,R2,R3) of the sliding surfaces of the sliding shoe (6) and the piston (3) have the same centre of curvature (10) and therefore the same fulcrum, damage to the sliding surfaces is avoided.
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