Axial piston pump

Claim 1

In an axial piston pump assembly of the type including a housing, a cover for said housing, a drive shaft rotatably supported within said housing and having an inner race thereon, a drive flange, universal means coupling said drive flange to said drive shaft, a hanger for supporting said drive flange, a cylinder block, a cylinder block spring, a plurality of pistons in said cylinder block having connecting rods coupled to said drive flange, and means for selectively delivering a pressure fluid to said plurality of pistons to transmit power to said drive flange to rotatably drive said drive shaft, the improvement comprising: a spherical socket engaged with and disposed between said inner race on said drive shaft and said drive flange, said spherical socket comprises, in combination, a hold-down ring disposed about said drive shaft and having a spherical-shaped outer side wall, and a ring disposed about said drive shaft and having a spherical-shaped inner side wall correspondingly formed to seatingly and slidably receive the spherical-shaped outer side wall of said hold-down ring therein, said hold-down ring being formed to abuttingly engage with said inner race on said drive shaft and said ring being formed to seat within said drive flange, the thrust of said cylinder block spring being imposed on said drive shaft and transmitted by said drive shaft to said spherical socket and said drive flange to retain the latter seated within said hanger.