Patent ID: 7594397
Filing Date: 2009-09-29
Classification: F16H

Abstract:
1. A clutch mechanism for a hydrostatic continuously variable transmission in which a hydraulic circuit including a high pressure oil path for feeding working oil from a hydraulic pump to a hydraulic motor and a low pressure oil path for feeding working oil from said hydraulic motor to said hydraulic pump is constituted between said hydraulic pump and said hydraulic motor in a casing rotated by a driving source within a cylinder integral with a transmission shaft, a clutch valve arranged in the transmission shaft is slid by a centrifugal governor, said high pressure oil path and said low pressure oil path are shortened to change-over a transmittance of power, comprising: a cam plate member arranged at an end part of said transmission shaft, the cam plate member including multiple sloping cam plate grooves extending diagonally along an inner surface of the cam plate member; a roller that is received by said cam plate grooves, the roller being adapted to move in an outward direction with a centrifugal force along the sloping cam plate grooves that extend diagonally along the inner surface of the cam plate member; a roller bearing member adapted to receive a roller pressing force caused by an outward motion of said roller, which in turn causes the roller bearing member to slide along an axial line of the transmission shaft; and a spring member adapted to bias said roller bearing member toward said roller; a spring sheet member adapted to support said spring member, wherein said spring member is disposed a predetermined distance relative to said cam plate member and is supported by the casing for the clutch mechanism, and wherein the cam plate member and the spring sheet member have end faces extending orthogonally to the axial line of the transmission shaft that abut against one another.