Externally actuated torque coupling for drivetrain

• US 20070191172A1
• Filed: 02/15/2006
• Published: 08/16/2007
• Est. Priority Date: 02/15/2006
• Status: Active Grant

• Current Assignee: Dana Automotive Systems Group, LLC (Dana, Inc.)
• Original Assignee: Dana Automotive Systems Group, LLC (Dana, Inc.)
• Inventors: Yoshioka, Jun
• Granted Patent: US 7,452,301 B2
• Time in Patent Office: Days
• US Class Current: 475/231
• CPC Class Codes: B60K 17/344 having a transfer gear
• CPC Class Codes: F16H 2048/204 Control of arrangements for suppressing differential actions
• CPC Class Codes: F16H 2048/423 characterised by bearing arrangement
• CPC Class Codes: F16H 48/08 comprising bevel gears
• CPC Class Codes: F16H 48/22 using friction clutches or brakes
• CPC Class Codes: F16H 48/27 using internally-actuatable fluid pressure, e.g. internal pump types
• CPC Class Codes: F16H 48/30 using externally-actuatable means
• CPC Class Codes: F16H 48/32 using fluid pressure actuators
• CPC Class Codes: F16H 48/40 characterised by features of the rotating cases

Abstract

A torque-coupling device comprising a hydraulically actuated friction clutch pack and a gerotor pump provided for generating hydraulic pressure actuating the friction clutch pack. The gerotor pump is selectively actuated by a device external to the gerotor pump and the friction clutch pack, such as an electric motor, friction brake, electro-magnetic clutch, friction mechanism utilizing a magneto-rheological fluid, electro-magnetic brake, etc. The externally driven gerotor pump may be further provided with torque-multiplication gearing, and/or an electronic controller to modulate the actuation of the pump in order to provide flexible control of the hydraulic pressure generated by the gerotor pump.

Claims

1. A torque coupling unit comprising:

an input member and at least one output member;

a clutch assembly for selectively coupling said input member with said at least one output member;

a normally deactivated hydraulic pump provided to generate a hydraulic pressure to frictionally load said clutch assembly; and

a pump actuator for selectively actuating said hydraulic pump, said pump actuator disposed externally to said clutch assembly.

2. The torque coupling unit according to claim 1, wherein said clutch assembly and said hydraulic pump are disposed within a rotating case and said pump actuator is disposed outside said rotating case.

3. The torque coupling unit according to claim 1, wherein said rotating case is a differential case housing a differential mechanism receiving torque from said input member and delivering torque to two output members.

4. The torque coupling unit according to claim 2, wherein said hydraulic pump comprises a rotor and a stator, and wherein said stator is drivingly coupled to said rotating case and said rotor is drivingly coupled to said pump actuator which is disposed outside said rotating case.

5. The torque coupling unit according to claim 4, wherein said torque member is a rotatable sleeve shaft coaxial with said at least one output member.

6. The torque coupling unit according to claim 1, wherein said pump actuator is a torque coupling device interposed between a stationary housing and said torque member to control actuation of said hydraulic pump.

7. The torque coupling unit according to claim 6, wherein said torque coupling device controls a rotation of said rotor relative to said stator to control a pump action of said hydraulic pump.

8. A torque transmission coupling for an axle of a four-wheel-drive vehicle, said torque transmission coupling comprising:

a two-part differential case having a first housing and a second housing;

a ring gear secured to and transmitting an input torque to said first housing;

at least one pinion and side gear assembly secured to and receiving an output torque from said second housing;

a multi-disc clutch mechanism adapted to transmit torque from said first housing to said second housing when said multi-disc clutch mechanism is in an engaged position, a first set of clutch plates being secured to said first housing and a second set of clutch plates being secured to said second housing;

a hydraulic pump system provided to generate a hydraulic pressure to frictionally load said clutch mechanism;

a pump actuator for selectively actuating said hydraulic pump, said pump actuator disposed externally to said first and second housings;

wherein both said speed sensitive pump actuation system and said clutch mechanism are disposed within said first and second housings.

9. The torque transmission coupling according to claim 8, wherein said hydraulic pump is responsive to a relative rotation between said first housing and said pump actuator to thereby actuate said multi-disc clutch mechanism.

10. The torque transmission coupling according to claim 8, wherein said hydraulic pump comprises a rotor and a stator, and wherein said stator is drivingly coupled to said first housing and said rotor is drivingly coupled to pump actuator which extends outside said first housing.

11. The torque transmission coupling according to claim 10, wherein said pump actuator comprises a rotatable sleeve shaft coaxial with at least one pinion and side gear assembly.

12. The torque transmission coupling according to claim 11, wherein said pump actuator is a torque coupling device interposed between a stationary housing and said sleeve shaft to control actuation of said hydraulic pump.

13. The torque transmission coupling according to claim 12, wherein said torque coupling device controls a rotation of said rotor relative to said stator to control a pump action of said hydraulic pump.