Vehicle differential and method of operating the same

Patent metadata

Field	Value
Publication number	US-9644726-B2
Application number	US-201414537948-A
Country	US
Kind code	B2
Filing date	Nov 11, 2014
Priority date	Nov 11, 2014
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

A differential and method of operating the differential is described. The differential has side gears and at least one pinion gear in mesh with the side gears. One of the side gears is provided with dog clutch teeth and an axially extending ring carrying clutch plates. A clutch housing has an axially extending ring carrying clutch plates interleaved with the side gear clutch plates. A dog clutch ring is connected to the clutch housing and selectively engages with the side gear dog clutch teeth. The above-described system permits an axle system of a tandem axle system to be selectively engaged and disengaged.

First claim

I claim:

1. A differential, comprising:
a differential case;
a first side gear, a second side gear and at least a first pinion gear in mesh with said first and said second side gears located within said differential case, wherein said first side gear is splined to a first axle half shaft, wherein said second side gear has an axially inboard face with teeth meshed with said pinion gear and an axially outboard face with dog clutch teeth and a second side gear axially extending ring, wherein an axially inboard direction is a direction toward a center of the differential, and an axially outboard direction is a direction away from the center of the differential;
a clutch housing within said differential case having an axially inboard portion and an axially outboard portion, said axially outboard portion comprising an axially outboard ring concentric with a second axle half shaft, wherein said axially inboard portion comprising a first axially extending ring and a second axially extending ring, wherein said first and second axially extending rings are concentric with one another, wherein said first axially extending ring is splined to said second axle half shaft;
a clutch pack within said clutch housing comprising a plurality of interleaved clutch plates comprising a first set of clutch plates splined to said second side gear axially extending ring and a second set of clutch plates splined to said clutch housing second axially extending ring; and
a dog clutch ring within said housing, said dog clutch ring splined to an outer surface of said second axially extending ring, said ring having a dog clutch teeth thereon.

2. The differential of claim 1 , wherein a dog clutch piston is connected to an axially outboard side of said dog clutch ring to selectively move said dog clutch ring along said splined outer surface of said clutch housing in axially inboard direction into engagement with said side gear dog clutch teeth.

3. The differential of claim 2 , wherein a first fluid channel is connected to said dog clutch piston and a second fluid channel is connected to a friction clutch piston.

4. The differential of claim 1 , wherein a biasing structure is located between said dog clutch ring and said clutch housing to bias said dog clutch ring out of engagement with said second side gear.

5. The differential of claim 1 , wherein said dog clutch ring is located radially outward from, and concentric with, said clutch plates.

6. The differential of claim 1 , wherein said clutch housing first axially extending ring is concentric with and radially inboard said second side gear axially extending ring, which is concentric with and radially inboard said clutch housing second axially extending ring, which is concentric with and radially inboard said dog clutch ring.

7. The differential of claim 1 , wherein said first axially extending ring and said second axially extending ring are connected to a base plate and said base plate is connected to said axially outboard ring.

8. The differential of claim 7 , wherein at least one fluid channel extends through said axially outboard ring, said base plate and at least one of said first or second axially extending rings of said clutch housing.

9. The differential of claim 7 , wherein a first thrust washer is located between said base plate and said differential case and a second thrust washer is located between said first side gear and said differential case.

10. A method of operating a differential, comprising:
biasing a friction clutch piston located in a differential into selective engagement with a set of interleaved clutch plates comprising a first set of clutch plates slidingly engaged to a side gear axially extending ring in said differential and a second set of clutch plates slidingly engaged with a clutch housing axially extending ring in said differential so that said second set of clutch plates imparts rotation to said first set of clutch plates to bring said first set of clutch plates to a first predetermined rotational value, wherein a dog clutch ring is radially outward mounted for rotation with a said clutch housing;
biasing said dog clutch ring into engagement with a said side gear with a dog clutch piston so that said side gear and said clutch housing rotate at the same speed, said clutch housing being connected to an axle shaft by another axially extending ring of said clutch housing;
wherein said clutch housing axially extending ring rotates radially inward of said side gear axially extending ring, which rotates radially inward of said dog clutch ring.

11. The method of claim 10 , wherein said differential is part of a first axle system, said first axle system being selectively connected to an input shaft and an interaxle differential for rotation therewith.

12. The method of claim 11 , further comprising locking said interaxle differential so that rotation from said input shaft does not rotate said first axle system but permitting rotation from said input shaft to rotate a second axle system.

13. The method of claim 11 , further comprising locking said interaxle differential so rotation from said input shaft rotates both said first axle system and a second axle system.

14. The method of claim 11 , further comprising opening said interaxle differential so rotation from said input shaft rotates both said first axle system and a second axle system.

15. The method of claim 10 , wherein said differential is part of a first axle system, said first axle system being selectively connected to an input shaft and a planetary differential for rotation therewith.

Assignees

• Dana Heavy Vehicle Sys Group

Inventors

• Cooper Kenneth E

Classifications

• F16H48/38

  Constructional details (the outer casing comprising the differential and supporting input and output shafts F16H57/037) · CPC title

• F16H48/24

  using positive clutches or brakes · CPC title

• F16H48/06

  with gears having orbital motion · CPC title

• F16H2048/387

  Shields or washers · CPC title

• F16H48/32

  using fluid pressure actuators · CPC title