초록 ▼

The housing of a hydrokinetic torque converter in the power train between the engine and the transmission of a motor vehicle contains a lockup valve which can be engaged to transmit torque directly from the output element of the engine to the output member of the turbine in the housing. Engagement o

The housing of a hydrokinetic torque converter in the power train between the engine and the transmission of a motor vehicle contains a lockup valve which can be engaged to transmit torque directly from the output element of the engine to the output member of the turbine in the housing. Engagement of the lockup clutch at a relatively low RPM of the engine and/or under certain other circumstances is prevented or minimized by the provision of one or more valves which are designed to establish or to at least partially seal one or more paths for direct flow of hydraulic fluid between two compartments forming part of a chamber in the housing of the torque converter and being disposed at opposite sides of the axially movable piston of the lockup clutch. The valve or valves can be designed to react in response to changing RPM of the housing of the torque converter, in response to changes of the temperature of hydraulic fluid in the housing and/or in response to changes of the viscosity of such fluid. The valving element or elements of the valve or valves can be caused to change its or their position(s) relative to the respective path(s) in response to the action of centrifugal force and/or due to direct contact with hydraulic fluid in the housing of the torque converter.

대표청구항 ▼

[ What is claimed is:] [1.] A torque transmitting apparatus comprising a hydrokinetic torque converter having a fluid-containing chamber and including a pump rotatable about a predetermined axis at a variable RPM by a rotary output element of a prime mover, and a turbine disposed in said chamber and

[ What is claimed is:] [1.] A torque transmitting apparatus comprising a hydrokinetic torque converter having a fluid-containing chamber and including a pump rotatable about a predetermined axis at a variable RPM by a rotary output element of a prime mover, and a turbine disposed in said chamber and including an output member rotatable about said axis; a lockup clutch engageable to transmit torque of variable magnitude from said output element to said output member and disengageable to interrupt the transmission of torque from said output element to said output member, said clutch including a piston rotatable at a plurality of speeds and movable in the direction of said axis and dividing said chamber into first and second compartments respectively containing bodies of a fluid at first and second pressures, the differential between said pressures determining the magnitude of torque being transmitted by said clutch; and at least one valve which is adjustable to establish at least one path for the flow of fluid between said compartments at a rate which varies as a function of variations of the RPM of the piston to thus influence the pressure differential and hence the magnitude of torque being transmitted by said clutch, said at least one valve being operative to permit the flow of fluid between said compartments in response to a reduction of said RPM of said piston to below a predetermined RPM and to at least reduce the rate of fluid flow between said compartments in response to a rise of the RPM of said piston above said predetermined RPM, said at least one valve comprising at least one valving element which is acted upon and is movable by centrifugal force in response to rotation of said piston to thereby reduce the rate of fluid flow between said compartments, said at least one valve further comprising means for yieldably urging said at least one valving element in a direction to increase the rate of fluid flow between said compartments.