Back to results
US 6,997,299 B2Granted
Hydraulic clutch actuation system
AssigneeMAGNA Powertrain AG & Co KG
InventorsJames S. Brissenden, Timothy M. Burns, Sankar K. Mohan, Eric A. Bansbach, Steven W. O'Hara
Life of this patent
Estimating the term…
Abstract
A torque transfer mechanism for controlling the magnitude of a clutch engagement force exerted on a clutch pack that is operably disposed between a first rotary member and a second rotary member includes a hydraulic clutch actuation system. The hydraulic clutch actuation system includes a primary fluid circuit coupled to a secondary fluid circuit by a pressure intensifier. The pressure intensifier provides magnified pressure to a piston for actuating the clutch pack.
Claims32
A power transmission device comprising:
- a rotary input member adapted to receive drive torque from a source of torque;
- a rotary output member adapted to provide drive torque to an output device;
- a torque transfer mechanism operable for transferring drive torque from said input member to said output member, said torque transfer mechanism including a friction clutch assembly operably disposed between said input member and said output member and a hydraulic clutch actuation system operable for applying a clutch engagement force to said friction clutch assembly, said hydraulic clutch actuation system including a primary fluid circuit and a separate secondary fluid circuit interconnected by a pressure intensifier, said second fluid circuit including a piston selectively engageable with said friction clutch assembly;
- and
- a controller to establish the value of an electric control signal based on a rotary speed difference between said input member and said output member, and wherein said control signal is operable to vary the pressure supplied to said piston chamber for causing torque to be transferred by said friction clutch assembly.
2 more elements
A transfer case for use in a motor vehicle having a powertrain and first and second drivelines, comprising:
- a first shaft driven by the powertrain and adapted for connection to the first driveline;
- a second shaft adapted for connection to the second driveline;
- a torque transfer mechanism operable for transferring drive torque from said first shaft to said second shaft, said torque transfer mechanism including an input member driven by said first shaft, an output member driving said second shaft, a friction clutch assembly operably disposed between said input member and said output member, and a hydraulic clutch actuation system operable for applying a clutch engagement force on said friction clutch assembly, said hydraulic clutch actuation system including a fluid pressure source coupled to a pressure intensifier, said pressure intensifier supplying magnified pressure to a piston, said piston being operable for applying said clutch engagement force.
A power transmission device comprising:
- a rotary input member adapted to receive drive torque from a source of torque;
- a rotary output member adapted to provide drive torque to an output device;
- and
- a torque transfer mechanism operable for transferring drive torque from said input member to said output member, said torque transfer mechanism including a friction clutch assembly operably disposed between said input member and said output member and a hydraulic clutch actuation system operable for applying a clutch engagement force to said friction clutch assembly, said hydraulic clutch actuation system including a primary fluid circuit and a secondary fluid circuit interconnected by a pressure intensifier, said secondary fluid circuit operable in a first mode to apply said clutch engagement force to said friction clutch assembly and a second mode to couple a pump member to a continuously driven member to provide lubrication to said friction clutch assembly.
1 more element
A method of actuating a clutch in a power transmission device, the method comprising:
- selectively supplying a pressurized fluid to a low pressure side of a pressure intensifier;
- selectively supplying magnified pressure from a high pressure side of said pressure intensifier to a piston;
- engaging the clutch with said piston to drivingly interconnect two rotary members;
- maintaining a desired pressure range within a low pressure accumulator of a primary fluid circuit by selectively operating a first control valve for coupling a low pressure source to said accumulator;
- and
- maintaining a desired pressure range in a secondary fluid circuit, said secondary fluid circuit being coupled to said primary circuit by said pressure intensifier, wherein the step of maintaining a desired pressure in a secondary fluid circuit includes operating a second control valve of said primary fluid circuit to selectively supply fluid from said low pressure accumulator to said low pressure side of said pressure intensifier, and wherein the step of supplying magnified pressure to said piston includes receiving a torque request from a controller, comparing the pressure applied to said piston with the pressure available at said high pressure side of said pressure intensifier and modulating a third control valve interconnecting said pressure intensifier and said piston to control the clutch to meet said torque request.
3 more elements
A method of actuating a clutch in a power transmission device, the method comprising:
- selectively supplying a pressurized fluid to a low pressure side of a pressure intensifier;
- selectively supplying magnified pressure from a high pressure side of said pressure intensifier to a piston;
- engaging the clutch with said piston to drivingly interconnect two rotary members;
- and
- coupling a pump component to a driven shaft of the power transmission device and pumping lubricant on the clutch by said pump component being coupled to said driven shaft by supplying magnified pressure from said high pressure side of said pressure intensifier to a second piston.
2 more elements
A transfer case comprising:
- a first output shaft adapted to transfer drive torque from a source of torque to a first driveline;
- a second output shaft adapted to provide drive torque to a second driveline;
- and
- a torque transfer mechanism operable for transferring drive torque from said first output shaft to said second output shaft, said torque transfer mechanism including a friction clutch assembly operably disposed between said first and second output shafts and a hydraulic clutch actuation system operable for applying a clutch engagement force to said friction clutch assembly, said hydraulic clutch actuation system including a primary fluid circuit and a separate secondary fluid circuit interconnected by a pressure intensifier, said second fluid circuit including a piston selectively engageable with said friction clutch assembly.
1 more element
A power transmission device for use in a motor vehicle comprising:
- a rotary input member adapted to receive drive torque from a powertrain;
- a rotary output member adapted to provide drive torque to a differential of an axle assembly;
- and
- a torque transfer mechanism operable for transferring drive torque from said input member to said output member, said torque transfer mechanism including a friction clutch assembly operably disposed between said input member and said output member and a hydraulic clutch actuation system operable for applying a clutch engagement force to said friction clutch assembly, said hydraulic clutch actuation system including a primary fluid circuit and a separate secondary fluid circuit interconnected by a pressure intensifier, said second fluid circuit including a piston selectively engageable with said friction clutch assembly.
1 more element
Dependencies are inferred from the claim text.