A hydraulic rotary machine configured to reduce sliding resistance of a reciprocating piston and to suppress a reduction in volumetric efficiency corresponding to an amount of leakage of hydraulic oil. A piston pump includes a rotor shaft, a cylinder block, a piston head, a piston rod, a retainer, a swash plate, and a tilt regulation mechanism. When the tilt regulation mechanism rocks the swash plate, the amount of discharge from the piston pump is variably changed. The retainer which rotates with both the piston head and the piston rod is supported by a retainer bush provided to the rotor shaft. The retainer sphere section of the retainer and the retainer bush sphere section of the retainer bush have spherical shapes having the same curvature. During the regulation of tilt, the retainer rocks while the retainer bush sphere section is in sliding contact with the retainer bush.

The present disclosure relates to a coupling assembly for a variable displacement hydraulic unit. The coupling assembly may have a rotatable swashplate, a swashplate bearing including a cage and a plurality of rollers mounted on the cage, a pin fixed to the swashplate, and a coupling member rotatably supported on the pin. The coupling member is configured to contact a portion of the cage to move the swashplate bearing upon rotation of the swashplate

The present disclosure relates to a coupling assembly for a variable displacement hydraulic unit. The coupling assembly may have a rotatable swashplate, a swashplate bearing including a cage and a plurality of rollers mounted on the cage, a pin fixed to the swashplate, and a coupling member rotatably supported on the pin. The coupling member is configured to contact a portion of the cage to move the swashplate bearing upon rotation of the swashplate

A bearing assembly having an inner race, an outer race, and a plurality of rollers positioned between the inner race and the outer race. A pad is attached to the inner race and a bed is attached to the outer race. A timing mechanism is slidably mounted to the pad and the bed. Preferably the pad and bed are made of plastic and the inner race is embedded within the pad and the outer race is embedded within the bed.

A bearing assembly having an inner race, an outer race, and a plurality of rollers positioned between the inner race and the outer race. A pad is attached to the inner race and a bed is attached to the outer race. A timing mechanism is slidably mounted to the pad and the bed. Preferably the pad and bed are made of plastic and the inner race is embedded within the pad and the outer race is embedded within the bed.

An example pump includes: (i) a swash block having (a) a first trunnion arm, (b) a second trunnion arm, and (c) a first curved support surface and a second curved support surface disposed on an exterior surface of the swash block; and (ii) a housing comprising (a) a first bore, (b) a second bore, and (c) an internal chamber having a first curved bushing and a second curved bushing, where the swash block is supported within the internal chamber of the housing by the first trunnion arm being positioned in the first bore of the housing, the second trunnion arm being positioned in the second bore of the housing, the first curved support surface being positioned against the first curved bushing of the housing, and the second curved support surface being positioned against the second curved bushing of the housing.

An example pump includes: (i) a swash block having (a) a first trunnion arm, (b) a second trunnion arm, and (c) a first curved support surface and a second curved support surface disposed on an exterior surface of the swash block; and (ii) a housing comprising (a) a first bore, (b) a second bore, and (c) an internal chamber having a first curved bushing and a second curved bushing, where the swash block is supported within the internal chamber of the housing by the first trunnion arm being positioned in the first bore of the housing, the second trunnion arm being positioned in the second bore of the housing, the first curved support surface being positioned against the first curved bushing of the housing, and the second curved support surface being positioned against the second curved bushing of the housing.

A thrust bearing assembly is provided for the pistons of a hydrostatic drive motor. The thrust bearing assembly includes first and second retainer components removably interconnected to form a retainer assembly, a thrust bearing captured between and encompassed by the first and second retainer components, and locking tangs extending outward from the first and second retainer components. Corresponding catches are formed on the internal surface of the housing to engage the locking tangs when the thrust bearing assembly is installed in the housing.

A thrust bearing assembly is provided for the pistons of a hydrostatic drive motor. The thrust bearing assembly includes first and second retainer components removably interconnected to form a retainer assembly, a thrust bearing captured between and encompassed by the first and second retainer components, and locking tangs extending outward from the first and second retainer components. Corresponding catches are formed on the internal surface of the housing to engage the locking tangs when the thrust bearing assembly is installed in the housing.

A variable wobbler plate has a stub shaft and a pivot shaft. The pivot shaft has a smaller diameter portion and a larger diameter portion. The smaller diameter portion has a generally cylindrical outer periphery with a flat over a limited circumferential extent and a diameter to opposed portions of the generally cylindrical portion defining a first distance. A second distance is defined from an end of the smaller diameter portion spaced furthest from the stub shaft to an end of the larger diameter portion spaced closest to the stub shaft and measured along a central axis of the pivot shaft and defines a second distance. A ratio of the first distance to the second distance is between 0.60 and 0.75. An integrated drive generator and a method are also disclosed.