Importance

Loading Importance Indicators...

Abstract

A variable displacement, rotary fluid pressure pump (11) is disclosed of the type having a cam ring member (25) which is movable, in response to rotation of a control shaft (35), between a neutral position (FIG. 5) and a displaced position (FIG. 4). The pump housing (13, 15) includes a support member (25), and they cooperate to define a high-pressure fluid passage (51). In communication with the passage (51) is a recess (71), in which is disposed a dampening shoe (73). The dampening shoe is biased by high-pressure fluid in the passage (51) into engagement with an adjacent surface (77) of the cam ring (25). The surface (77) defines a neutral fluid passage (79), and the dampening shoe (73) defines a restricted opening (85). When the cam ring (25) is in the displaced position, the restricted opening (85) is blocked from communication with the neutral passage (79), but as the cam ring is returned to its neutral position, the opening (85) begins to communicate with the neutral passage (79), thus providing the pump with an increased neutral band overlap.

Loading the Abstract Image...

First Claim