Self-adjusting servo mechanism for actuating a friction band assembly in a planetary gear set

Abstract

The present invention is directed to a self-adjusting servo mechanism (10). That is, the servo pin (30) presented from the servo mechanism (10) will protract sufficiently to effect operative engagement of a friction band assembly (13) with a rotating member (18) in a planetary gear set--even though the required axial displacement of the servo pin (30) during such protraction may exceed the axial displacement available to the actuating piston (33). The servo mechanism (10) is incorporated in a housing (20). The housing (20) presents a socket cavity (24) within which an actuating piston (33) is received for axial displacement through a predetermined distance. The servo pin (30) is supported by the housing (20) for axial reciprocation, and a coupling means (35) is interposed between the servo pin (30) and the actuating piston (33) operatively to protract the servo pin (30) in response to displacement of the actuating piston (33). The coupling means (35) is axially extensible within a predetermined range automatically to effect that displacement of the servo pin (30) required to actuate the friction band assembly (13). As such, the servo mechanism (10) is self-adjusting.

Dependencies are inferred from the claim text.