Valve device of a pneumatically actuatable friction clutch

Patent metadata

Field	Value
Publication number	US-12135091-B2
Application number	US-202117794349-A
Country	US
Kind code	B2
Filing date	Jan 11, 2021
Priority date	Jan 23, 2020
Publication date	Nov 5, 2024
Grant date	Nov 5, 2024

Abstract

A valve device ( 2 ), of a pneumatically actuatable friction clutch engageable by spring force, includes at least one inlet valve ( 16, 18 ) connected on the input side to a pressurized supply line and on the output side to an actuating cylinder of the friction clutch. A pressure-sustaining valve ( 20, 28 ) is upstream or downstream of the inlet valve and is designed as a check valve closing in the backflow direction. The pressure-sustaining valve is a springless check valve and includes a housing ring ( 22, 30 ) having a retaining basket ( 36 ), a closing element ( 24, 32 ), and a valve seat ( 26, 34 ). The closing element, in the depressurized state and with a positive pressure gradient is held in the retaining basket ( 36 ) of the housing ring ( 22, 30 ) and, with a negative pressure gradient is pressed out of the retaining basket ( 36 ) and against the valve seat ( 26, 34 ).

First claim

The invention claimed is:

1. A valve device ( 2 ) for a pneumatically actuatable friction clutch arranged in a vehicle between a drive motor and a gearbox, which friction clutch is configured to be engaged by means of spring force, the valve device comprising:
at least one inlet valve ( 16 , 18 ), which is connectable on an inlet side of the at least one inlet valve to a pressurized supply line and on an outlet side of the at least one inlet valve to a working chamber of an actuating cylinder of the friction clutch, the at least one inlet valve designed as a 2/2-way solenoid seat valve,
wherein the working chamber of the friction clutch is configured for being connected to an outlet valve, which outlet valve is connectable on an inlet side of the outlet valve to the working chamber of the actuating cylinder and on an outlet side of the outlet valve to a vent outlet, and the outlet valve is designed as a 2/2-way solenoid seat valve, and
a pressure-sustaining valve ( 20 , 28 ), which is arranged upstream or downstream of the inlet valve ( 16 , 18 ) and is designed as a check valve which closes in the backflow direction,
wherein the pressure-sustaining valve ( 20 , 28 ) is designed as a check valve without a valve spring and comprises:
a housing ring ( 22 , 30 ) having a retaining cage ( 36 ),
a closing element ( 24 , 32 ), and
a valve seat ( 26 , 34 ),
wherein the closing element ( 24 , 32 ) of the pressure-sustaining valve ( 20 , 28 ), in a depressurized state and/or with a positive pressure gradient from the direction of an outlet bore of the associated inlet valve ( 16 , 18 ) defined as when pressure in the supply line is higher than in the working chamber of the actuating cylinder, is held by interlocking and frictional engagement in the retaining cage ( 36 ) of the housing ring ( 22 , 30 ) and,

wherein the closing element ( 24 , 32 ) of the pressure-sustaining valve ( 20 , 28 ), with a negative pressure gradient in the direction of the outlet bore of the associated inlet valve ( 16 , 18 ) defined as when pressure in the supply line is lower than in the working chamber of the actuating cylinder, can be lifted out of the retaining cage ( 36 ) and pressed against the valve seat ( 26 , 34 ) to block pressurized air from exiting the working chamber through the at least one inlet valves.

2. The valve device as claimed in claim 1 , wherein the retaining cage ( 36 ) of the housing ring ( 22 , 30 ) comprises retaining webs ( 38 a , 38 b , 38 c ) which are formed radially on the inside of the housing ring ( 22 , 30 ) and are arranged in a manner distributed around the circumference, and wherein the retaining webs ( 38 a , 38 b , 38 c ) each have an inner surface ( 40 a , 40 b , 40 c ) in the form of a segment of a circle, which inner surfaces together form a retaining geometry, in the form of a segment of a sphere, of the retaining cage ( 36 ).

3. The valve device as claimed in claim 2 , wherein the closing element ( 24 , 32 ) of the pressure-sustaining valve ( 20 , 28 ) is of spherical design and has a spring-elastic surface ( 44 ).

4. The valve device as claimed in claim 3 , wherein the closing element ( 24 , 32 ) is composed entirely of a spring-elastic material.

5. The valve device as claimed in claim 3 , wherein the closing element ( 24 , 32 ) has a core of a hard material, and wherein the core is coated with a spring-elastic material.

6. The valve device as claimed in claim 3 , wherein the closing element ( 24 , 32 ) has a central cavity which is surrounded in the form of a spherical shell by the spring-elastic material.

7. The valve device as claimed in claim 3 , wherein the spring-elastic material of the closing element ( 24 , 32 ) is rubber.

8. The valve device as claimed in claim 3 , wherein the spring-elastic material of the closing element ( 24 , 32 ) is silicone rubber.

9. The valve device as claimed in claim 2 , wherein apertures are defined circumferentially between the retaining webs, through which apertures pressurized air will flow when the closing element is held by the holding ring, the inlet valve is open, and the pressure in the supply line greater than the pressure in the working chamber.

10. The valve device as claimed in claim 9 , wherein the apertures are arranged circumferentially around the closing element when the closing element is held in the retaining cage.

11. The valve device as claimed in claim 1 , wherein the pressure-sustaining valve ( 20 , 28 ) is connected downstream of the inlet valve ( 16 , 18 ) and is arranged adjacent the outlet bore of the inlet valve ( 16 , 18 ), and wherein the edge of the outlet bore of the inlet valve ( 16 , 18 ) serves as and/or is designed as a valve seat ( 26 , 34 ) of the pressure-sustaining valve ( 20 , 28 ).

12. The valve device as claimed in claim 1 , wherein the closing element ( 24 , 32 ) is pressed against the valve seat in response to a drop in pressure in the supply line when the inlet valve is open to maintain a pressurized state in the working chamber of the friction clutch.

13. The valve device as claimed in claim 12 , wherein the closing element is held in the retaining cage and moved from the retaining cage without a spring force applied thereto.

14. The valve device as claimed in claim 1 , wherein, during the positive pressure gradient when the pressure in the supply line is greater than the pressure in the working chamber, pressurized air flows past the closing element and through the holding ring toward the working chamber when the closing element is pressed against and held by the closing ring and the inlet valve is open.

15. The valve device as claimed in claim 14 , wherein during the negative pressure gradient when the pressure in the supply line drops below the pressure in the working chamber, pressurized air flows through the holding ring and presses the closing element against the valve seat, and is blocked from flowing through the inlet valve when the inlet valve is open.

16. The valve device as claimed in claim 1 , wherein the at least one inlet valve includes two inlet valves each having an associated connecting channel in communication with a common outlet channel for connecting to the working chamber of the friction clutch, wherein the connecting channels are connected in parallel to the outlet channel.

17. The valve device as claimed in claim 1 , wherein the closing member remains retained in the holding ring during normal pressurization and depressurization of the working chamber of the friction clutch via controlled opening and closing of the inlet and outlet valves, and the closing element shifts out of retention from the holding ring only in response to a fault in the supply line in which the pressure in the supply line drops and backflow from the pressurized working chamber forces the closing element out of the holding ring.

18. The valve device as claimed in claim 1 , wherein pressurized air from the supply line flows past the closing element and to the working chamber when the closing element is held in the retaining ring and the inlet valve is opened.

19. The valve device as claimed in claim 1 , wherein the closing element is held in the retaining ring without a spring force applied thereto.

20. The valve device as claimed in claim 19 , wherein the closing element is moved out of the retaining without a spring force applied thereto.

Assignees

• Zf Cv Systems Europe Bv

Inventors

• Didwiszus Lars
• Karstens Hauke
• Günther Michael

Classifications

• F16K15/048

  Ball features · CPC title

• F16K15/1823

  for ball check valves · CPC title

• F16D2048/0221

  Valves for clutch control systems; Details thereof · CPC title

• F16K15/04

  shaped as balls · CPC title

• F16D25/14

  Fluid pressure control · CPC title