Transfer Case with Oil Distribution

Patent metadata

Field	Value
Publication number	US-2018010682-A1
Application number	US-201715639546-A
Country	US
Kind code	A1
Filing date	Jun 30, 2017
Priority date	Jul 7, 2016
Publication date	Jan 11, 2018
Grant date	—

Abstract

A transfer case comprises a primary output shaft, a secondary output shaft, a clutch, and a plurality of valves. The primary output shaft includes a hub rotationally coupled thereto. The clutch is selectively couples the primary output shaft to the secondary output shaft to transfer torque therebetween. The clutch includes a housing, interleaved plates, and an apply plate. The housing is rotationally coupled to the secondary output shaft. The interleaved plates alternate between a first subset of the interleaved plates rotationally coupled to the hub, and a second subset of the interleaved plates rotationally coupled to the housing. The apply plate compresses the interleaved plates for transferring torque between the hub and the housing. The valves selectively release oil supplied through the primary output shaft into the housing. Each valve includes a bore formed in the hub and a valve rod movable by the apply plate to open the valve.

First claim

1 . A transfer case comprising:
a primary output shaft having a hub rotationally coupled thereto; a secondary output shaft; a clutch configured to selectively couple the primary output shaft to the secondary output shaft to transfer torque therebetween, the clutch comprising:
a housing rotationally coupled to the secondary output shaft;
a plurality of interleaved plates that alternate between a first subset of the interleaved plates that are rotationally coupled to the hub and a second subset of the interleaved plates that are rotationally coupled to the housing; and
an apply plate configured to compress the plurality of interleaved plates for transferring torque between the hub and the housing; and
a plurality of valves configured to selectively release oil supplied through the primary output shaft into the housing, each valve having a bore formed in the hub and a valve rod movable by the apply plate to open the valve.

2 . The transfer case according to claim 1 , wherein each valve is a spool valve.

3 . The transfer case according to claim 2 , wherein each bore extends parallel with an axis of the primary output shaft.

4 . The transfer case according to claim 3 , wherein the valves are circumferentially spaced evenly about the axis of the primary output shaft.

5 . The transfer case according to claim 1 , wherein each bore extends parallel to an axis of the primary output shaft and includes a plurality of inlets that are spaced axially along an axis of the bore.

6 . The transfer case according to claim 5 , wherein for each bore, the plurality of inlets are in fluidic communication with each other external to the bore.

7 . The transfer case according to claim 6 , wherein the hub has an inner periphery that defines a plurality of axial channels, and each axial channel is associated with one of the bores and places the plurality of inlets of the bore in fluidic communication with each other.

8 . The transfer case according to claim 7 , wherein the primary output shaft includes one or more radial conduits through which oil is communicated to the valves, and the plurality of axial channels are in fluidic communication with the one or more radial conduits.

9 . The transfer case according to claim 8 , wherein the primary output shaft includes a central conduit, two radial conduits in fluidic communication with the central conduit, and a peripheral channel in fluidic communication with the two radial conduits, and the plurality of axial channels of the hub are in fluidic communication with the peripheral channel of the primary output shaft.

10 . The transfer case according to claim 1 , wherein each valve rod is movable in an axial direction parallel with an axis of the primary output shaft to open the valve for oil to flow through the valve in a radial direction.

11 . The transfer case according to claim 10 , wherein each bore includes a plurality of inlets in an inner periphery of the hub and a plurality of outlets in an outer periphery of the hub, each inlet being aligned with one of the outlets; and
wherein each valve rod includes a plurality of grooves, each groove being movable into simultaneous alignment with one of the inlets and one of the outlets to open the valve.

12 . The transfer case according to claim 11 , wherein each groove is arranged circumferentially around the valve rod, has an axial length, and is associated with one of the inlets, and each inlet has an axial length that is greater than a compression distance of the interleaved plates.

13 . The transfer case according to claim 12 , wherein the axial length of the inlet is greater than or equal to a sum of the axial length of the groove associated therewith and the compression distance.

14 . The transfer case according to claim 1 , further comprising return springs that are each associated with one of the valves and compress the valve rod of the valve associated therewith against the apply plate.

15 . The transfer case according to claim 14 , wherein the apply plate is moved axially between a first position in which the interleaved plates are not compressed and a second position in which the interleaved plates are compressed, and the return springs move the apply plate to the first position.

16 . A transfer case comprising:
a primary output shaft; a secondary output shaft; a torque transfer mechanism for selectively transferring torque between the primary output shaft and the secondary output shaft; a lubrication system for lubricating the torque transfer mechanism; and an actuation system, wherein the actuation system simultaneously operates the torque transfer mechanism and the lubrication system.

17 . The transfer case according to claim 16 , wherein the torque transfer mechanism includes a clutch and the actuation system includes one or more valves, and the actuation system opens the valves by operating the clutch.

18 . The transfer case according to claim 17 , wherein the valves are opened by the clutch prior to the clutch transferring torque between the primary output shaft and the secondary output shaft.

19 . The transfer case according to claim 18 , wherein the clutch includes:
a hub rotationally coupled to the primary output shaft; a housing rotationally coupled to the secondary output shaft; a plurality of interleaved plates that alternate between a first subset of the interleaved plates that are rotationally coupled to the hub and a second subset of the interleaved plates that are rotationally coupled to the housing; and an apply plate configured to compress the plurality of interleaved plates for transferring torque between the hub and the housing; and wherein the one or more valves are configured to selectively release oil supplied through the primary output shaft into the housing, and each valve includes a bore formed in the hub and a valve rod movable by the apply plate to open the valve.

20 . A torque transfer device comprising:
a first shaft; a second shaft; a clutch for selectively coupling the first shaft and the second shaft to transfer torque therebetween, wherein the clutch includes:
a hub rotationally fixed around the first shaft;
a housing rotationally coupled to the second shaft;
a plurality of interleaved plates that are alternatingly rotationally coupled to the hub and to the housing;
an apply plate configured to compress the plurality of interleaved plates for transferring torque between the hub and the housing, and
valves incorporated into the hub for selectively releasing oil radially from the first shaft into the housing, the valves being opened by movement of the apply plate.

Assignees

• Borgwarner Inc

Inventors

• Pritchard Larry
• Sullivan Christopher

Classifications

• B60K17/02

  characterised by arrangement, location, or kind of clutch · CPC title

• F16H57/0473

  Friction devices, e.g. clutches or brakes · CPC title

• B60K17/352

  manually operated · CPC title

• F16H57/0446

  the supply forming part of the transmission control unit, e.g. for automatic transmissions · CPC title

• F16H57/0435 Primary

  Pressure control for supplying lubricant; Circuits or valves therefor · CPC title