Patent ID: 6840696

Claim:
In a method of producing a ball-and-socket joint ( 1 ) between a slipper ( 3 ) and a piston ( 2 ) of a piston machine, including the steps of: a) configuring the slipper ( 3 ) with a joint ball ( 4 ) at an end opposite a bottom surface ( 21 ) thereof; b) configuring the piston ( 2 ) at an oversized dimension (x) on a lateral surface ( 2 c ) and with a hemispherical joint recess ( 5 ) having a free recess edge ( 7 ) protruding beyond the maximum diameter ( 6 ) of the joint recess ( 5 ) at one end of the piston ( 2 ); c) and finishing the lateral surface ( 2 c ) of the piston ( 2 ); the improvement comprising: d) inserting the joint ball ( 4 ) into the joint recess ( 5 ) after finishing the lateral surface ( 2 c ) of the piston ( 2 ) as set forth in step c): e) locally heating the free recess edge ( 7 ) to a temperature reducing the hardness of the material thereof; and f) hot-beading the free recess edge ( 7 ) into a circumferentially converging configuration for confining said joint ball ( 4 ) within said joint recess ( 5 ).