Torque transmitting unit and power train having a torque transmitting unit

• US 20060000684A1
• Filed: 06/20/2005
• Published: 01/05/2006
• Est. Priority Date: 06/21/2004
• Status: Active Grant

• Current Assignee: Schaeffler Technologies AG & Co.KG (INA-Holding Schaeffler GmbH & Co. KG)
• Original Assignee: LuK Lamellen und Kupplungsbau Beteiligungs KG (INA-Holding Schaeffler GmbH & Co. KG)
• Inventors: Agner, Ivo, Nohl, Oliver, Bergmann, Jochen
• Granted Patent: US 7,455,159 B2
• Time in Patent Office: Days
• US Class Current: 192/48.800
• CPC Class Codes: F16D 13/72 Features relating to cooling
• CPC Class Codes: F16D 2021/0661 Hydraulically actuated multiple lamellae clutches
• CPC Class Codes: F16D 21/06 at least two driving shafts or two driven shafts being concentric
• CPC Class Codes: F16D 25/10 Clutch systems with a plurality of fluid-actuated clutches arrangements or mounting of clutches in vehicles B60K17/00
• CPC Class Codes: F16H 57/0434 relating to lubrication supply, e.g. pumps arrangement of pumps F16H57/0441; Pressure control grooves with pumping effect for supplying lubricant F16H57/0428; generation and variation of line pressure for transmission control F16H61/0021

Abstract

A torque transmitting unit in the power train of a motor vehicle for transmitting torque between an engine crankshaft, and a transmission having at least one input shaft with at least one friction clutch. The transmission input shaft is coupled with the crankshaft by the friction clutch, which includes friction disks on the power input and/or output sides, and that are pressed together axially along an axis of rotation of the transmission input shaft to form a frictional engagement through a plurality of disks arranged in alternating layers in the axial direction. The disks are pressed against a stop by an actuator and with an actuating bearing interposed, wherein the actuator is connected to a fixed part of the transmission housing in a rotationally fixed connection. The friction clutch is a wet clutch.

Claims

1. A torque transmitting unit for a motor vehicle power train for transmitting torque between an engine having an output shaft and a transmission having at least one transmission input shaft, said torque transmitting unit comprising:

a friction clutch operatively connected between the engine output shaft and the at least one transmission input shaft, the clutch including a plurality of alternating frictional components stacked in an axial direction;

an operating member arranged to transmit an axial force to press the frictional components together;

an actuator far applying an axial force to the operating member and connected to a fixed housing part in a rotationally fixed connection;

an operating bearing positioned between the actuator and the operating member to permit rotation of the operating member relative to the actuator;

wherein the friction clutch is operated as a wet mode clutch.

3. A torque transmitting unit according to claim 1, wherein at least one actuator is an actuator selected from the group consisting of electromechanical, electrohydraulic, and electropneumatic actuators.

4. A torque transmitting unit according to claim 3, including an electric motor rotary drive positioned substantially perpendicular to a transmission input shaft for applying pressure to at least one friction clutch, including means for converting the rotary motion of the rotary drive to a linear motion along one of the transmission input shafts to apply pressure to a corresponding operating bearing.

5. A torque transmitting unit according to claim 3, including an electric motor rotary drive positioned substantially parallel to a transmission input shaft for applying pressure to at least one friction clutch, including means for converting the rotary motion of the rotary drive to a linear motion along one of the transmission input shafts to apply pressure to a corresponding operating bearing.

6. A torque transmitting unit according to claim 1, including a pump for providing a stream of fluid to cool at least one friction clutch and positioned adjacent a clutch housing that is between the engine and a wall of the transmission.

7. A torque transmitting unit according to claim 6, wherein the pumped fluid serves as a coolant for the clutch and as a lubricant is used for pump drive gears.

8. A torque transmitting unit according to claim 6, wherein the pump is driven by a component operatively connected with the engine output shaft.

9. A torque transmitting unit according to claim 6, wherein the pump is an internal gear pump having a ring gear with an internal tooth system, with which a sun gear with an external tooth system meshes, a suction crescent to draw the fluid, and wherein the sun gear is supported by means of its an external tooth system on a segment of the suction crescent that is complementary thereto.

10. A torque transmitting unit according to claim 6, wherein the pump is a gerotor pump having a ring gear with an internal tooth system, with which a sun gear with an external tooth system meshes.

11. A torque transmitting unit according to claim 9, wherein the sun gear of the pump includes a bearing stub which supports the sun gear on one side.

12. A torque transmitting unit according to claim 9, wherein the ring gear is operatively coupled with a pump drive gear through one of a lug, an insert, and as a single piece in a rotationally fixed coupling arrangement.

13. A torque transmitting unit according to claim 12, wherein the pump drive gear meshes with a second drive gear that is coupled to an input part of one of the friction clutches in a rotationally fixed coupling by a coupling device that transfers torque and also serves as an oil guide.

14. A torque transmitting unit according to claim 13, wherein the coupling device has at least one drive lug that engages a lug recess provided on the second drive gear.

15. A torque transmitting unit according to claim 13 or 14, wherein the coupling device has a passage section with connecting grooves which are positioned between the second drive gear and a bearing device by which the second drive gear is supported on a transmission input shaft.

16. A torque transmitting unit according to claim 13, wherein the coupling device includes a section having a tooth system through which the coupling device is connected to a coupling element in a rotationally fixed connection for axial movement of the coupling device relative to the coupling element.

17. A torque transmitting unit according to claim 16, wherein the coupling element includes a centering section that is in contact with one of an operating bearing and a diaphragm spring finger.

18. A torque transmitting unit according to claim 16, wherein the coupling element is coupled directly with a clutch outer disk carrier.

19. A torque transmitting unit according to claim 12, wherein the pump includes a pump cover that is in contact with the second drive gear.

20. A torque transmitting unit according to claim 12, wherein the pump is mounted on a transmission housing section that is in axial contact with the second drive gear.

21. A torque transmitting unit according to claim 6, including a suction throttle for regulating a volumetric flow produced by the pump.

22. A torque transmitting unit according to claim 21, wherein the volumetric pump flow is conducted through a through hole in the sun gear of the pump.

23. A torque transmitting unit according to claim 20, wherein flow control is accomplished by means of an electromagnetic intake regulating valve.

24. A torque transmitting unit according to claim 6, including an oil cooler connected between the pump and a friction clutch.

25. A torque transmitting unit according to claim 23, wherein a housing around the intake regulating valve, a valve piston of the intake regulating valve, a pump cover, and the pump gears are made of plastic.

26. A torque transmitting unit according to claim 23, wherein the electromagnetic intake regulating valve includes a valve piston having a linking channel that enables fluid to pass through the valve piston as the valve piston moves back and forth, to provide for pressure equalization.

27. A torque transmitting unit according to claim 26, wherein the valve piston is received within a blind bore formed in a transmission housing section and sufficient free play is provided between the valve piston and the bore to enable coolant to pass therebetween as the valve piston moves back and forth, to provide for pressure equalization.

28. A torque transmitting unit according to claim 26, wherein a notch is provided on an outside diameter of the valve piston to enable coolant to pass through as the valve piston moves back and forth, to provide for pressure equalization.

29. A double clutch transmission having a torque transmitting unit according to claims 1.

30. A power train with an engine and a double clutch transmission, having a torque transmitting unit according to claim 1 positioned therebetween.

31. A torque transmitting unit according to claim 1, including a pump for providing a stream of fluid to cool at least one friction clutch and positioned within a wall of the double clutch transmission.

32. A torque transmitting unit according to claim 6, wherein the pump is driven by a separate electric motor.

33. A torque transmitting unit according to claim 23, wherein the plastic is a thermosetting material.

2. A torque transmitting unit for a motor vehicle power train for transmitting torque between an engine having an output shaft and a transmission having at least two transmission input shafts, said torque transmitting unit comprising:

a respective friction clutch operatively positioned between each transmission input shaft and the engine output shaft;

each friction clutch including a respective friction unit that is engaged by an axially-directed pressing force applied in a direction along an axis of rotation of at least one of the transmission input shafts to form a frictional engagement, wherein the friction units are each formed from a plurality of alternating frictional components stacked in an axial direction, and wherein the friction units of the two friction clutches are positioned radially one above the other;

the friction units of each friction clutch individually are pressed against a stop by means of an actuator assigned to the particular friction unit;

a respective operating member associated with each friction unit for pressing together the frictional components

a respective actuator for applying an axial force to a respective operating member and connected to a fixed housing part in a rotationally fixed connection;

a respective operating bearing positioned between the actuator and the operating member of a respective friction unit to permit rotation of the operating member relative to the actuator;

wherein both friction clutches are operated as wet mode clutches.

34. A torque transmitting unit according to claim 2, wherein at least one actuator is an actuator selected from the group consisting of electromechanical, electrohydraulic, and electropneumatic actuators.