Rotary slide valve with a thermostatic bypass

• US 9,115,634 B2
• Filed: 05/04/2010
• Issued: 08/25/2015
• Est. Priority Date: 05/06/2009
• Status: Active Grant

• Current Assignee: Audi AG (Volkswagen AG)
• Original Assignee: Audi AG (Volkswagen AG)
• Inventors: Triebe, Steffen, Staiger, Michael, Helling, Lars, Lachner, Dieter
• Primary Examiner(s): Norman, Marc
• Assistant Examiner(s): SNOW, MAXWELL B
• Application Number:
  US13/318,854
• Publication Number:
  US 20120055652A1
• Time in Patent Office: 1,939 Days
• Field of Search: 236/12.11, 236/12.13, 236/12.15, 236/92.C, 236/93.R
• US Class Current: 1/1
• CPC Class Codes: F01P 2005/105 Using two or more pumps
• CPC Class Codes: F01P 2007/146 using valves
• CPC Class Codes: F01P 2025/32 Engine outcoming fluid temperature
• CPC Class Codes: F01P 2031/00 Fail safe
• CPC Class Codes: F01P 7/16 by thermostatic control
• CPC Class Codes: F01P 7/161 by bypassing pumps
• CPC Class Codes: F01P 7/165 characterised by systems with two or more loops
• CPC Class Codes: F04D 15/0022 throttling valves or valves varying the pump inlet opening or the outlet opening

Abstract

The invention relates to a fail-safe rotary actuator (1) for a coolant circuit, in particular for a coolant circuit of an internal combustion engine (2) having a plurality of sub-circuits (3) and (4), includes a coolant delivery pump (5) for circulating the coolant within the coolant circuit, and having a rotary-slide housing (8) which has a plurality of housing pass-through openings (6) and (7) and in which at least one rotary slide (9) having at least one rotary slide pass-through opening (11) and (12) is rotatably supported, wherein the housing pass-through openings (6) and/or (7) are fluidly connected to at least one sub-circuit (3) and/or (4), and can be brought into at least partial coincidence with the rotary slide pass-through openings (11) and/or (12) by a rotary motion of the rotary slide (9), wherein a thermostat valve (13) opens a flow path running parallel to the rotary slide (9) from one of the sub-circuits (3) or (4) to the coolant delivery pump (5), when a temperature limit of the coolant is exceeded.

Claims

1. A fail-safe rotary actuator for a coolant circuit, comprising:

a pump for circulating a coolant within the coolant circuit;

a rotary-slide housing having a plurality of housing pass-through openings which are fluidly connected to a sub-circuit of the coolant circuit, the sub-circuit having a radiator, an inlet line, and an outlet line, the plurality of housing pass-through openings including

     1) an opening that accepts fluid form the inlet line,

     2) an opening that accepts fluid from the outlet line, and

     3) an opening that delivers fluid to the pump;

at least one rotary slide valve having at least one rotary slide pass-through opening and supported in the rotary-slide housing for rotation to enable at least partial coincidence of the housing pass-through openings with the rotary slide pass-through opening; and

a thermostat valve adapted to open a flow path running parallel to the rotary slide from the outlet line directly to the pump, when a temperature limit of the coolant in the inlet line is exceeded as detected by an expansion member of said thermostat valve, said expansion member in communication with the coolant in the inlet line by extending into the inlet line.

2. The fail-safe rotary actuator of claim 1, constructed for a coolant circuit of an internal combustion engine, with the coolant circuit having a plurality of sub-circuits.

3. The fail-safe rotary actuator of claim 1, wherein the inlet line is constructed for conducting coolant from an internal combustion engine to the radiator.

4. The fail-safe rotary actuator of claim 3, wherein the thermostat valve comprises a shut-off valve is supported in a valve seat, said thermostat valve having a spring to press the shut-off valve snugly against the valve seat, and a push rod arranged on the shut-off valve, said expansion member configured to actuate the push rod and to expand when a temperature limit of the coolant is reached to thereby lift the shut-off valve away from the valve seat via the push rod in opposition to a pressure applied by the spring.

5. The fail-safe rotary actuator of claim 4, wherein the thermostat valve has chambers arranged on opposite sides of the shut-off valve and acted upon by coolant, with a first one of the chambers receiving coolant from the outlet line, and a second one of the chambers having a fluid communication to a suction port of the pump.

6. The fail-safe rotary actuator of claim 5, wherein the rotary slide valve and the rotary-slide housing define a gap for allowing flow of coolant from the second chamber of the thermostat valve to the suction port of the pump.

7. The fail-safe rotary actuator of claim 2, wherein one of the sub-circuits is a heating circuit, said pump conveying coolant drawn in from the rotary slide valve to the heating circuit and/or a supply line to the internal combustion engine.

8. The fail-safe rotary actuator of claim 7, wherein the heating circuit includes at least one member selected from the group consisting of a heating heat exchanger, heating delivery pump, and heating shut-off valve.

9. The fail-safe rotary actuator of claim 1, further comprising a further shut-off valve arranged in a supply line to an internal combustion engine.

10. The fail-safe rotary actuator of claim 9, wherein the further shut-off valve is configured in the form of a rotary slide valve.

11. The fail-safe rotary actuator of claim 8, wherein the heating shut-off valve is opened, when a temperature limit of the coolant is exceeded so that coolant from the coolant delivery pump is able to flow via the heating heat exchanger to the internal combustion engine.

12. A method of controlling coolant flow in a coolant circuit, comprising:

pumping coolant within a coolant circuit, the coolant circuit having a sub-circuit with an inlet line, and outlet line, and a radiator;

directing coolant flow via a rotary-slide valve situated within a rotary-slide housing, the housing having a plurality of pass-through openings that are fluidly connected to the sub-circuit, the plurality of housing pass through openings including

     1) an opening that accepts fluid from the inlet line,

     2) an opening that accepts fluid from the outlet line, and

     3) an opening that delivers fluid to a pump;

rotating said rotary slide valve with respect to said housing to enable at least partial coincidence of the housing pass-through openings with the rotary slide pass-through opening;

detecting whether a temperature of coolant in the inlet line has exceeded a temperature limit with an expansion member of a thermostat valve, said expansion member communicating with coolant in the inlet line by extending into the inlet line; and

opening said thermostat valve when coolant exceeds the temperature limit, thus opening a bypass running parallel to the rotary slide, from the outline line directly to the pump.

13. The method of claim 12, wherein the inlet line accepts coolant from an internal combustion engine and wherein the sub-circuit is one of a plurality of sub-circuits.

14. The method of claim 13, further comprising pumping coolant drawn from the rotary slide to a heating circuit or a supply line to the internal combustion engine.

15. The method of claim 13, further comprising 1) exchanging heat in a heating sub-circuit via a heating heat exchanger or 2) pumping coolant in the heating sub-circuit with a heating delivery pump, or 3) actuating a heating sub-circuit shut-off valve.

16. The method of claim 13, further comprising actuating a shut-off valve in a heating sub-circuit, said shut-off valve configured as a rotary-slide valve, said actuation opening a flow path from a heating heat exchanger provided in the heating sub-circuit to the internal combustion engine.