Hydraulic control system

Patent metadata

Field	Value
Publication number	US-9856931-B2
Application number	US-201615056732-A
Country	US
Kind code	B2
Filing date	Feb 29, 2016
Priority date	Feb 29, 2016
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

A hydraulic control system includes a hydraulic pump driven by an electric motor, a solenoid valve having an output that controls the positions of a pressure regulator valve and a third, stator shift valve. The solenoid valve is a normally high, variable force solenoid valve which provides a control signal to the second and third valves. The second, pressure regulator valve is a multiple port valve which controls hydraulic fluid flow both to a transmission oil cooler (ATOC) and to an exhaust port, thereby maintaining a desired system pressure. The third, stator shift valve is also a multiple port valve and it controls fluid flow to the stator of the electric pump motor to provide cooling and to a dog clutch of the transmission to disengage it.

First claim

What is claimed is:

1. A fluid control system for a motor vehicle transmission comprising, in combination,
a pump having a fluid output and an electric motor driving said pump, said electric motor having a stator,
a solenoid valve communicating with said fluid output and providing a variable pressure output,
a pressure regulator valve having a control port communicating with said variable pressure output and an input port communicating with said fluid output,
a stator shift valve having a control port communicating with said variable pressure output, a first input port communicating with said fluid output and a first outlet port communicating with said stator of said electric motor,
a transmission fluid cooler having an inlet communicating with an outlet port of said pressure regulator valve and an outlet communicating with a second inlet port of said stator shift valve, and
a clutch having a fluid operator communicating with a second outlet port of said stator shift valve.

2. The hydraulic control system of claim 1 further including a sump communicating with a fluid inlet of said pump and exhaust ports of said solenoid valve, said pressure regulator valve and said stator shift valve.

3. The control system of claim 1 further including a spool having at least three lands disposed in each of said pressure regulator valve and said stator shift valve.

4. The control system of claim 1 further including a pressure relief valve disposed between said inlet and said outlet of said transmission fluid cooler.

5. The control system of claim 1 wherein said clutch is a dog clutch.

6. The control system of claim 5 wherein said dog clutch is normally engaged and fluid pressure in said fluid operator disengages said clutch.

7. The control system of claim 1 wherein said stator shift valve selectively supplies fluid to one of said stator of said electric motor and said fluid operator of said clutch.

8. A hydraulic control system for a motor vehicle automatic transmission comprising, in combination,
a hydraulic pump having a hydraulic fluid output and an electric motor driving said hydraulic pump, said electric motor having a stator,
a variable force solenoid valve communicating with said hydraulic fluid output of said pump and providing a variable pressure fluid signal,
a pressure regulator valve having a control port communicating with said variable pressure fluid signal and an input port communicating with said hydraulic fluid output,
a stator shift valve having a control port communicating with said variable pressure fluid signal, a first input port communicating with said hydraulic fluid output and a first outlet port communicating with said stator of said electric motor,
a transmission fluid cooler having an inlet communicating with an outlet port of said pressure regulator valve and an outlet communicating with a second inlet port of said stator shift valve, and
a clutch having a hydraulic operator in fluid communication with a second outlet port of said stator shift valve.

9. The hydraulic control system of claim 8 further including a sump in fluid communication with a hydraulic fluid inlet of said hydraulic pump and exhaust ports of said variable force solenoid valve, said pressure regulator valve and said stator shift valve.

10. The hydraulic control system of claim 8 further including a spool having at least three lands disposed in each of said pressure regulator valve and said stator shift valve.

11. The hydraulic control system of claim 8 further including a pressure relief valve disposed between said inlet and said outlet of said transmission fluid cooler.

12. The hydraulic control system of claim 8 wherein said clutch is a dog clutch.

13. The hydraulic control system of claim 12 wherein said dog clutch is normally engaged and hydraulic fluid pressure in said hydraulic operator disengages said dog clutch.

14. The hydraulic control system of claim 12 wherein said stator shift valve selectively supplies hydraulic fluid to one of said stator of said electric motor and said hydraulic operator of said clutch.

15. A hydraulic control system for a motor vehicle automatic transmission comprising, in combination,
a hydraulic pump having a hydraulic fluid output and an electric motor driving said hydraulic pump, said electric motor having a stator,
a variable force solenoid valve communicating with said hydraulic fluid output of said pump and providing a variable pressure fluid signal,
a pressure regulator valve having a control port communicating with said variable pressure fluid signal and an input port communicating with said hydraulic fluid output,
a stator shift valve having a control port communicating with said variable pressure fluid signal, a first input port communicating with said hydraulic fluid output and a first outlet port communicating with said stator of said electric motor,
a transmission fluid cooler having an inlet communicating with an outlet port of said pressure regulator valve and an outlet communicating with a second inlet port of said stator shift valve, and
a clutch having a hydraulic operator in fluid communication with a second outlet port of said stator shift valve,
wherein said stator shift valve selectively supplies hydraulic fluid to one of said stator of said electric motor and said hydraulic operator of said clutch.

16. The hydraulic control system of claim 15 further including a sump in fluid communication with a hydraulic fluid inlet of said hydraulic pump and exhaust ports of said variable force solenoid valve, said pressure regulator valve and said stator shift valve.

17. The hydraulic control system of claim 15 wherein said clutch is a dog clutch and said dog clutch is normally engaged and hydraulic fluid pressure in said hydraulic operator disengages said dog clutch.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Neelakantan Vijay A
• Grewal Ajit Singh

Classifications

• F16D2048/0257

  Hydraulic circuit layouts, i.e. details of hydraulic circuit elements or the arrangement thereof · CPC title

• F16D25/123

  in view of cooling and lubrication · CPC title

• F16D2048/0209

  characterised by fluid valves having control pistons, e.g. spools · CPC title

• F16D11/14

  with clutching members movable only axially (F16D11/02, F16D11/08 take precedence) · CPC title

• F16D2048/0221

  Valves for clutch control systems; Details thereof · CPC title