US Patent 7757598 Hydrostatic bearing arrangement for pump swashplate having secondary angle

A hydraulic axial piston pump is designed with a secondary swashplate angle for providing improved performance and life. The secondary swashplate angle produces a sideload on the swashplate that is reacted by the pump's housing. A hydrostatically balanced thrust bearing is used to counteract the sideload produced by the secondary swashplate angle. The bearing design includes a tiltable pad or shoe supplied with pressurized fluid from the pump's discharge port. The same fluid that supplies the tiltable pad may also supply the pump's cradle bearings.