Hydraulic control unit having interface plate disposed between housing and pump

Patent metadata

Field	Value
Publication number	US-2016160982-A1
Application number	US-201615044704-A
Country	US
Kind code	A1
Filing date	Feb 16, 2016
Priority date	Aug 22, 2013
Publication date	Jun 9, 2016
Grant date	—

Abstract

A hydraulic control unit that delivers hydraulic fluid to a limited slip differential constructed in accordance to the present disclosure can include a hydraulic control unit housing, a motor, a gerotor gear assembly and an interface plate. The hydraulic control unit housing can have a housing mounting surface. The motor can include an output shaft and a motor mounting plate that has a motor mounting surface. The gerotor gear assembly can include an inner and outer gerotor gear. The outer gerotor gear can be formed of a first material having a first coefficient of expansion. The interface plate can be mounted between the housing mounting surface and the motor mounting surface. The interface plate can receive the outer gerotor gear in an interference fit. The interface plate is formed of a second material having a second coefficient of expansion that is substantially equivalent to the first coefficient of expansion.

First claim

What is claimed is:

1 . A hydraulic control unit that delivers hydraulic fluid to a limited slip differential, the hydraulic control unit comprising:
a hydraulic control unit housing having a housing mounting surface, the housing mounting surface defining a fluid inlet port therein; a motor having an output shaft and a motor mounting plate that has a motor mounting surface; a gerotor gear assembly including an inner gerotor gear and an outer gerotor gear, wherein the outer gerotor gear is formed of a first material having a first coefficient of expansion, the inner gerotor gear coupled for rotation with the output shaft; and an interface plate mounted between the housing mounting surface and the motor mounting surface, the interface plate having an inner diameter that defines an opening that receives the outer gerotor gear in an interference fit, wherein the interface plate is formed of a second material having a second coefficient of expansion and wherein the first and second coefficients of expansion are substantially equivalent.

2 . The hydraulic control unit of claim 1 wherein the interface plate and the outer gerotor gear are formed of the same material.

3 . The hydraulic control unit of claim 1 wherein the interface plate is formed of steel.

4 . The hydraulic control unit of claim 3 wherein the outer gerotor gear is formed of steel.

5 . The hydraulic control unit of claim 1 wherein the interface plate is formed of powdered metal.

6 . The hydraulic control unit of claim 5 wherein the outer gerotor gear is formed of powdered metal.

7 . The hydraulic control unit of claim 1 wherein the interface plate has a plurality of radially extending plate mounting ears that define a corresponding plurality of plate mounting apertures.

8 . The hydraulic control unit of claim 7 wherein the motor mounting plate has a plurality of radially extending motor mounting apertures.

9 . The hydraulic control unit of claim 8 wherein the hydraulic control unit housing defines a plurality of housing mounting apertures and wherein (i) the plurality of interface plate mounting apertures, (ii) the plurality of motor mounting apertures and (iii) the plurality of housing mounting apertures cooperatively align to receive a plurality of fasteners that secure the motor, interface plate and the hydraulic control unit housing together.

10 . The hydraulic control unit of claim 1 wherein the hydraulic control unit housing further comprises an integrally formed housing manifold portion that defines a fluid port configured to at least partially communicate hydraulic fluid between the accumulator housing portion and the limited slip differential.

11 . The hydraulic control unit of claim 1 , further comprising a pair of locating posts, wherein the hydraulic control unit housing defines a first pair of locating post apertures, the interface plate defines a second pair of locating post apertures and the motor mounting plate defines a third pair of locating post apertures, the pair of locating posts received by the first, second and third locating post apertures to inhibit relative rotation of the hydraulic control unit housing, interface plate and motor.

12 . The hydraulic control unit of claim 1 wherein the motor mounting plate defines a radial groove at a location radially outwardly of the output shaft, the radial groove receiving an o-ring that sealingly engages the interface plate.

13 . The hydraulic control unit of claim 1 wherein the hydraulic control unit housing is unitary and further comprises an accumulator housing portion and a sump housing portion.

14 . A hydraulic control unit that delivers hydraulic fluid to a limited slip differential, the hydraulic control unit comprising:
a hydraulic control unit housing having a housing mounting surface; a motor having an output shaft and a motor mounting plate that has a motor mounting surface; a gerotor gear assembly including an inner gerotor gear and an outer gerotor gear, wherein the outer gerotor gear is formed of steel, and wherein the inner gerotor gear is coupled for rotation with the output shaft; and an interface plate mounted between the housing mounting surface and the motor mounting surface, the interface plate engaged to the outer gerotor gear in fixed relationship, wherein the interface plate is formed of steel, wherein the steel outer gerotor gear and the steel interface plate are configured to thermally expand at a substantially similar rate.

15 . The hydraulic control unit of claim 14 wherein the interface plate has an inner diameter that defines an opening that receives the outer gerotor gear in an interference fit.

16 . The hydraulic control unit of claim 15 wherein the outer gerotor gear and the interface plate are formed of powdered metal.

17 . The hydraulic control unit of claim 14 wherein the interface plate has a plurality of radially extending plate mounting ears that define a corresponding plurality of plate mounting apertures, the motor mounting plate has a plurality of radially extending motor mounting apertures and the hydraulic control unit housing defines a plurality of housing mounting apertures and wherein (i) the plurality of interface plate mounting apertures, (ii) the plurality of motor mounting apertures and (iii) the plurality of housing mounting apertures cooperatively align to receive a plurality of fasteners that secure the motor, interface plate and the hydraulic control unit housing together.

18 . A hydraulic control unit that delivers hydraulic fluid to a limited slip differential, the hydraulic control unit comprising:
a hydraulic control unit housing having a housing mounting surface; a motor having an output shaft and a motor mounting plate that has a motor mounting surface; a gerotor gear assembly including an inner gerotor gear and an outer gerotor gear, wherein the outer gerotor gear is formed of powdered metal, and wherein the inner gerotor gear is coupled for rotation with the output shaft; and an interface plate mounted between the housing mounting surface and the motor mounting surface, the interface plate engaged to the outer gerotor gear in fixed relationship, wherein the interface plate is formed of powdered metal, wherein the powdered metal outer gerotor gear and the powdered metal interface plate are configured to thermally expand at a substantially similar rate.

19 . The hydraulic control unit of claim 18 wherein the outer gerotor gear and the interface plate are formed of steel.

20 . The hydraulic control unit of claim 18 wherein the interface plate has a plurality of radially extending plate mounting ears that define a corresponding plurality of plate mounting apertures, the motor mounting plate has a plurality of radially extending motor mounting apertures and the hydraulic control unit housing defines a plurality of housing mounting apertures and wherein (i) the plurality of interface plate mounting apertures, (ii) the plurality of motor mounting apertures and (iii) the plurality of housing mounting apertures cooperatively align to receive a plurality of fasteners that secure the motor, interface plate and the hydraulic control unit housing together.

Assignees

• Eaton Corp

Inventors

• Edler Andrew N
• Fisher Daniel P
• Grogg John A

Classifications

• F05C2201/0448

  Steel · CPC title

• F04C2230/22

  by sintering · CPC title

• F04C2240/30

  Casings or housings · CPC title

• F04C15/0023

  Axial sealings for working fluid · CPC title

• F01C21/108

  with an axial surface, e.g. side plates · CPC title