Patent ID: 8196485
Filing Date: 2012-06-12
Classification: F16D,F16H,Y10T

Abstract:
1. A twin clutch device used in an engine transmission having a main shaft, in which there are coaxially and adjacently arranged a first disk clutch and a second disk clutch of a hydraulic pressure type, wherein said first disk clutch displaces a first pressing member and said second disk clutch displaces a second pressing member, said first and second pressing members being displaced in an axial direction with externally supplied hydraulic pressure to exert a predetermined engagement force; and said first disk clutch and said second disk clutch respectively have: an engagement side hydraulic chamber that gives said first and second pressing members a pressing force towards a clutch engagement side; and a pressure compensation hydraulic chamber that gives said first and second pressing members a pressing force towards a clutch disengagement side to compensate a pressure of a returning action thereof, wherein the twin clutch device comprises: a first actuator that controls hydraulic pressure supply to said engagement side hydraulic chamber of said first disk clutch, and a second actuator that controls hydraulic pressure supply to said engagement side hydraulic chamber of said second disk clutch; a hydraulic pressure cut-off device that brings said first disk clutch and said second disk clutch into a disengagement state; and a first oil pump which supplies a pressure-feed oil in an engine, and a second oil pump which supplies a generate hydraulic pressure for operating said first disk clutch and said second disk clutch, and wherein said hydraulic pressure cut-off device comprises a hydraulic pressure relief valve and a hydraulic pressure switching valve, said hydraulic pressure relief valve being configured to open or cut-off hydraulic pressure relief oil passages, which are arranged at an upstream side of said first and second actuators, and said hydraulic pressure switching valve being configured to switch a hydraulic pressure supply passage between said first oil pump and said hydraulic pressure relief valve, when electric power is not applied to said hydraulic pressure switching valve, a part of said hydraulic pressure from said first oil pump is supplied to a relief side hydraulic chamber and a returning side hydraulic chamber, which are provided at both ends of said hydraulic pressure relief valve, wherein said hydraulic pressure relief valve is opened by a difference between a first biasing force with respect to said hydraulic pressure relief valve due to said hydraulic pressure supplied to said relief side hydraulic chamber and a second biasing force with respect to said hydraulic pressure relief valve due to said hydraulic pressure supplied to the returning side hydraulic chamber, to open said hydraulic pressure relief oil passages and release said supplied hydraulic pressure to said first and second actuators, and when the electric power is applied to said hydraulic pressure switching valve, said hydraulic pressure supplied from said first oil pump to said relief side hydraulic chamber ceases, wherein said hydraulic pressure relief valve is closed to cut-off said hydraulic pressure relief oil passages and supply said hydraulic pressure to said first and second actuators.