Driveline power transmitting component with a plate clutch-type limited slip differential assembly having preload disconnect capabilities

Patent metadata

Field	Value
Publication number	US-10837536-B2
Application number	US-201916257146-A
Country	US
Kind code	B2
Filing date	Jan 25, 2019
Priority date	Jan 25, 2019
Publication date	Nov 17, 2020
Grant date	Nov 17, 2020

Abstract

A driveline power transmitting device that includes a limited slip differential having a differential case, a cross-pin, a pair of pressure rings, a pair of clutch packs, a pair of preload springs, and a pair of preload control mechanisms. The pressure rings are non-rotatably coupled to the differential case and are disposed on opposite sides of the cross-pin. The preload springs bias the pressure rings toward the clutch packs and thereby preload the clutch packs. The pressure rings are urged axially away from the cross-pin to further compress the clutch packs in response to rotation of the cross-pin relative to the differential case. The preload control mechanisms are employed to decrease the preload force on the clutch packs in certain situations.

First claim

What is claimed is:

1. A driveline power transmitting device comprising:
a differential case;
a differential gearset received in the differential case, the differential gearset having a cross-pin, a plurality of differential pinions and a pair of side gears, the differential pinions being rotatably disposed on the cross-pin, each of the side gears being rotatable about an axis and meshingly engaged to the differential pinions;
a pair of clutch packs received in the differential case, each of the clutch packs having a plurality of first clutch plates and a plurality of second clutch plates, each of the first clutch plates being non-rotatably but axially slidably coupled to the differential case, each of the second clutch plates being interleaved with the first clutch plates and being non-rotatably but axially slidably coupled to a respective one of the side gears;
a pair of pressure rings, each of the pressure rings being non-rotatably but axially slidably coupled to the differential case and being disposed between the cross-pin and a respective one of the clutch packs;
a pair of preload spring sets;
a pair of first cams, each of the first cams being coupled for rotation with the cross-pin about the axis;
a pair of first followers, each of the first followers being coupled to an associated one of the pressure rings, wherein rotation of the cross-pin about the axis in a first rotational direction when the first cams are in contact with the first followers urges the pressure rings along the axis in directions away from the cross-pin; and
a pair of preload control mechanisms, each of the preload control mechanisms having a second cam, a second follower and a defeat spring, each of the second cams being coupled to an associated one of the pressure rings, each of the second followers being rotatably disposed about the axis relative to the pressure rings, the defeat springs biasing the second followers about the axis relative to the second cams such that the pressure rings are disposed in neutral positions in which a predetermined preload force is generated by each of the preload springs and transmitted to each of the clutch packs;
wherein when the pressure rings are disposed in the neutral positions and rotary power is transmitted through the differential gearset that causes the second followers to rotate about the axis in a second, opposite rotational direction relative to the second cams, the second followers and the second cams cooperate to reduce compression of the preload springs such that forces that are generated by the preload springs and exerted on the clutch packs are relatively lower than the predetermined preload force.

2. The driveline power transmitting device of claim 1 , wherein each of the preload springs is disposed along the axis between the cross-pin and an associated one of the pressure rings.

3. The driveline power transmitting device of claim 2 , wherein the preload springs are disposed along the axis between the second cams and the second followers.

4. The driveline power transmitting device of claim 2 , wherein the preload springs bias the second followers away from the cross-pin.

5. The driveline power transmitting device of claim 1 , wherein the second cams are non-rotatably coupled to the pressure rings and the second followers are movably coupled to the cross-pin.

6. The driveline power transmitting device of claim 5 , wherein the second followers are non-rotatably but axially movably coupled to the cross-pin.

7. The driveline power transmitting device of claim 5 , wherein the second followers are rotatably and axially movably coupled to the cross-pin.

8. The driveline power transmitting device of claim 1 , wherein the second followers are received into detents formed in the second cams when the pressure rings are in the neutral positions.

9. The driveline power transmitting device of claim 1 , wherein the preload springs comprise linear wave springs that are disposed between the second followers and the second cams.

10. The driveline power transmitting device of claim 1 , wherein the preload springs comprise a plurality of helical compression springs mounted to the cross-pin.

11. The driveline power transmitting device of claim 10 , wherein the second followers comprise follower elements that are received on ends of the helical compression springs that are opposite the cross-pin.

12. The driveline power transmitting device of claim 11 , wherein the follower elements comprise spherical balls.

13. The driveline power transmitting device of claim 10 , wherein the second followers comprise discrete structures that are assembled axially and rotationally between the cross-pin and the pressure rings.

14. The driveline power transmitting device of claim 1 , further comprising a center ring disposed within the differential case between the pressure rings and rotatable relative to the differential case about the axis, the cross-pin being non-rotatably coupled to the center ring, the first cams extending from opposite lateral sides of the center ring.

15. A driveline power transmitting device comprising:
a differential case;
a differential gearset received in the differential case, the differential gearset having a cross-pin, a plurality of differential pinions and a pair of side gears, the differential pinions being rotatably disposed on the cross-pin, each of the side gears being rotatable about an axis and meshingly engaged to the differential pinions;
a pair of clutch packs received in the differential case, each of the clutch packs having a plurality of first clutch plates and a plurality of second clutch plates, each of the first clutch plates being non-rotatably but axially slidably coupled to the differential case, each of the second clutch plates being interleaved with the first clutch plates and being non-rotatably but axially slidably coupled to a respective one of the side gears;
a pair of pressure rings, each of the pressure rings being non-rotatably but axially slidably coupled to the differential case and being disposed between the cross-pin and a respective one of the clutch packs;
a pair of preload spring sets;
a pair of first cams, each of the first cams being coupled to the cross-pin for rotation about the axis;
a pair of first followers, each of the first followers being coupled to an associated one of the pressure rings, wherein rotation of the first cams about the axis in a first rotational direction when the first cams are in contact with the first followers urges the pressure rings along the axis in directions away from the cross-pin; and
a pair of preload control mechanisms, each of the preload control mechanisms having a first member, a second member, and a defeat spring, the first member being rotatable relative to the second member between a neutral position and a preload defeat position, wherein the preload control mechanisms are wider along the axis when in the neutral position than when in the preload defeat position, the defeat springs biasing the preload control mechanisms toward the neutral position, wherein each of the preload control mechanisms is in a respective load path that includes an associated one of the preload springs and an associated one of the clutch packs.

16. The driveline power transmitting device of claim 15 , further comprising a center ring disposed within the differential case between the pressure rings and rotatable relative to the differential case about the axis, the cross-pin being non-rotatably coupled to the center ring, the first cams extending from opposite lateral sides of the center ring.

Assignees

• American Axle & Mfg Inc

Inventors

• Chemelli Douglas J
• Ettenhofer Ryan

Classifications

• F16D7/027

  with multiple lamellae · CPC title

• F16H48/08 Primary

  comprising bevel gears · CPC title

• F16H2048/085

  characterised by shafts or gear carriers for orbital gears · CPC title

• F16H48/22

  using friction clutches or brakes · CPC title

• F16D2023/123

  Clutch actuation by cams, ramps or ball-screw mechanisms · CPC title