Patent ID: 7201566

Claim:
A reciprocating-piston machine, in particular a refrigerant compressor ( 1 ) for a motor vehicle air-conditioning system, comprising: a rotatable machine shaft ( 2 ), a plurality of pistons ( 4 ) movably supported by piston guides ( 10 ) and having piston axes which extend parallel to, and are arranged all at the same distance from, the machine shaft ( 2 ) and in circumferentially spaced relationship, on a cylinder envelope around the machine shaft, an annular pivoting disc ( 5 ) extending around the machine shaft ( 2 ) and being connected to said machine shaft ( 2 ) so as to be driven thereby, each of said pistons ( 4 ) being engaged with said pivoting disc ( 2 ) by a joint arrangement ( 6 ), said joint arrangement ( 6 ) including an at least partially spherical receptacle with at least one bearing element ( 18 , 19 ) arranged in said receptacle moveably relative to an associated piston and relative to said pivoting disc, a first sliding element ( 18 , 20 ) having a first sliding face ( 18 a , 20 a ) in the form of a spherical segment, with a first geometric center of curvature (M 1 , M 3 ), and a second sliding element ( 19 , 21 ) having a second sliding face ( 19 a , 21 a ) in the form of a spherical segment, with a second geometric center of curvature (M 2 , M 4 ), said first and said second geometric centers of curvature being arranged at a distance from one another, said joint arrangement ( 6 ) having a center of force transmission (K) which is located approximately on said cylinder envelope defined by said piston axes and positioned in front of the associated piston axis ( 12 ) with respect to the direction of rotation of the pivoting disc ( 5 ).