Vacuum supply system

• US 8,297,263 B2
• Filed: 06/24/2011
• Issued: 10/30/2012
• Est. Priority Date: 03/03/2010
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Pursifull, Ross Dykstra
• Primary Examiner(s): SOLIS, ERICK R
• Application Number:
  US13/167,996
• Publication Number:
  US 20110247594A1
• Time in Patent Office: 494 Days
• Field of Search: 123/198.C, 123/518, 123/519, 603/97
• US Class Current: 123/518
• CPC Class Codes: F02B 37/162 by bypassing, e.g. partially, intake air from pump inlet to pump outlet
• CPC Class Codes: F02B 37/186 Arrangements of actuators or linkage for bypass valves
• CPC Class Codes: F02M 25/0836 Arrangement of valves controlling the admission of fuel vapour to an engine, e.g. valve being disposed between fuel tank or absorption canister and intake manifold
• CPC Class Codes: F02M 25/089 Layout of the fuel vapour installation
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A method of operating a boosted engine system is described in which an ejector coupled with a fuel vapor purging system can generate vacuum during both purging and non-purging conditions, and during both boosted and non-boosted conditions. The vacuum can therefore be used to power vacuum actuated brakes, and/or other vacuum actuators, irrespective of the purging conditions, and irrespective of boost levels.

Claims

1. A method of operating a boosted engine system, comprising,

pumping a purge flow through a fuel vapor canister and an ejector, and into an engine intake via a purge pump when boost is present;

drawing the purge flow through the fuel vapor canister and ejector, and into the engine intake via engine vacuum without operating the pump in the absence of boost; and

applying the ejector to a vacuum actuator.

2. The method of claim 1, wherein the vacuum actuator includes a power brake.

3. The method of claim 1, wherein the vacuum actuator includes a wastegate actuator.

4. The method of claim 1, wherein the ejector is positioned downstream of the purge pump.

5. The method of claim 1, wherein pumping a purge flow includes, opening a canister vent valve, closing a vapor bypass valve, and operating the pump.

6. The method of claim 5, further comprising,

pumping an air flow, while bypassing the fuel vapor canister, through the ejector and into the engine intake;

and

applying vacuum from the ejector to the vacuum actuator.

7. The method of claim 6, wherein pumping an air flow includes, closing the canister vent valve, opening the vapor bypass valve, and operating the pump.

8. The method of claim 1, wherein pumping a purge flow includes pumping the purge flow through the fuel vapor canister, then through the ejector, and then into the engine intake.

9. An engine method, comprising,

pumping a purge flow through a fuel vapor canister and an ejector, and into an engine intake via a pump when boost is present;

drawing the purge flow through the canister and ejector, and into the intake via engine vacuum without operating the pump;

pumping an air flow, while bypassing the canister, through the ejector and into the intake via the pump; and

applying the ejector to a vacuum actuator.

10. The method of claim 9, wherein the vacuum actuator includes a power brake.

11. The method of claim 9, wherein the vacuum actuator includes a wastegate actuator.

12. The method of claim 9, wherein the ejector is positioned downstream of the pump.

13. The method of claim 9, wherein pumping a purge flow includes, opening a canister vent valve, closing a vapor bypass valve, and operating the pump.

14. The method of claim 13, wherein pumping the air flow includes, closing the canister vent valve, opening the vapor bypass valve, and operating the pump.

15. The method of claim 10, wherein pumping a purge flow includes pumping the purge flow through the fuel vapor canister, then through the ejector, and then into the engine intake.

16. An engine system, comprising,

an engine intake;

a compressor configured to boost intake air;

a fuel vapor canister configured to receive fuel vapors from a fuel tank, the fuel vapor canister communicating with atmosphere via a first canister vent valve and a second vapor bypass valve;

a purge pump;

an ejector coupled downstream of the pump;

a conduit with a plurality of check valves coupled between the ejector and upstream and downstream of the compressor;

a vacuum actuator; and

a controller configured to,

operate the compressor to provide a boost; and

in the presence of boost,

operate the purge pump to pump a purge flow through the fuel vapor canister, through the ejector, into the engine intake, during purging conditions; and

operate the purge pump to pump an air flow bypassing the fuel vapor canister, through the ejector, into the engine intake, during non-purging conditions; and

during purging and non-purging conditions, apply vacuum from the ejector to the vacuum actuator.

17. The system of claim 16, wherein pumping a purge flow includes opening the canister vent valve and closing the vapor bypass valve, and wherein pumping an air flow includes opening the vapor bypass valve and closing the canister vent valve.

18. The system of claim 17, wherein the vacuum actuator is one of a power brake and a wastegate actuator, and wherein the controller is further configured to, in the absence of boost,

apply vacuum from the engine intake on the fuel vapor canister and/or ejector.

19. The system of claim 16, wherein pumping a purge flow to the engine intake includes driving at least some purge flow to the engine intake downstream of an intake throttle, and driving at least some purge flow to the engine intake upstream of the compressor.