Robert D Ash

US Patent:

58293388, Nov 3, 1998

Filed:

Mar 3, 1997

Appl. No.:

8/811084

Inventors:

Brian M. Chrestoff - Sidney OH
Robert H. Ash - Humble TX

Assignee:

FMC Corporation - Chicago IL

International Classification:

F01B 300
F16C 3206

US Classification:

92 122

Abstract:

This invention pertains to a single-piece unidirectional tapered land thrust bearing cluster for use in high-pressure positive-displacement swashplate piston pumps and the like. The bearing cluster has a plurality of identical bearing pads integral to the bearing cluster. Each bearing pad includes a tapered section, a flat section and a fluid communicating slot integral therewith. During operation of the pump the swashplate camming surface rotates relative to the bearing cluster which develops a pressurized load-carrying hydrodynamic film of decreasing thickness and increasing strength between a back plate of the rotating swashplate and the bearing cluster.

US Patent:

57849480, Jul 28, 1998

Filed:

Aug 18, 1997

Appl. No.:

8/912743

Inventors:

Brian M. Chrestoff - Sidney OH
Robert H. Ash - Humble TX

Assignee:

FMC Corporation - Chicago IL

International Classification:

F01B 1304
F04B 112

US Classification:

92 57

Abstract:

A positive displacement pump including a plurality of pistons reciprocally driven in respective cylinders by a swashplate assembly to expel fluid during the pressure stroke of the piston from a chamber in communication with each piston. Oppositely disposed magnets are located respectively in an upper pressure face of each piston and in a check valve housing adjacent each cylinder to produce a magnetic force circuit accelerating movement of each piston toward and in continual contact with a cluster bearing associated with the swashplate assembly during the suction stroke of each piston. Like poles of each magnet face each other to produce a permanent levitating force on each piston.