Method of managing pressure in a fuel system

• US 6,983,641 B1
• Filed: 05/05/2000
• Issued: 01/10/2006
• Est. Priority Date: 11/19/1999
• Status: Expired due to Fees

• Current Assignee: Continental Automotive GmbH (Continental AG)
• Original Assignee: Continental Automotive GmbH (Continental AG)
• Inventors: Perry, Paul D., Cook, John E.
• Primary Examiner(s): GARBER, CHARLES D
• Application Number:
  US09/565,028
• Time in Patent Office: 2,076 Days
• Field of Search: 123/520, 137/81.1, 137/115.13, 73/37, 200/81.4, 200/83.R, 200/83.Q
• US Class Current: 73/37
• CPC Class Codes: F02M 2025/0845 Electromagnetic valves
• CPC Class Codes: F02M 25/0809 Judging failure of purge control system
• 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

Abstract

An integrated pressure management system manages pressure and detects leaks in a fuel system. The integrated pressure management system also performs a leak diagnostic for the headspace in a fuel tank, a canister that collects volatile fuel vapors from the headspace, a purge valve, and all associated hoses and connections.

Claims

1. A method of managing pressure created in a fuel tank of a fuel system for an engine, comprising:

providing an integrated assembly including;

a switch actuatable in response to the pressure created in the fuel tank; and

a pressure operable device actuatable to relieve the pressure created in the fuel tank, the pressure operable device including a diaphragm being displaced in response to a negative pressure at a first pressure level; and

signaling with the switch the negative pressure at the first pressure level, the signaling providing a leak diagnostic of the fuel system after the engine is turned off, the method further comprising actuating the pressure operable device with a solenoid.

2. The method according to claim 1, further comprising:

actuating the pressure operable device to relieve negative pressure below the first pressure level.

3. The method according to claim 1, further comprising:

actuating the pressure operable device to relieve positive pressure above a second pressure level.

4. The method according to claim 1, wherein the providing an integrated assembly includes:

providing a housing defining an interior chamber, the housing including first and second ports communicating with the interior chamber, the pressure operable device separating the chamber into a first portion and a second portion, the first portion communicating with the first port, the second portion communicating with the second port, the pressure operable device permitting fluid communication between the first and second ports in a first configuration and preventing fluid communication between the first and second ports in a second configuration; and

providing a solenoid displacing the device from the first configuration to the second configuration.

5. The method according to claim 4, wherein the switch signals displacement of the diaphragm in response to the negative pressure at the first pressure level in the first portion of the interior chamber.

6. A method of managing pressure created in a fuel tank of a fuel system for an engine, the method comprising:

displacing a diaphragm in response to a first level of negative pressure created in the fuel tank;

signaling with a switch the first level of negative pressure created in the fuel tank, the signaling providing a leak diagnostic of the fuel system after the engine is turned off; and

relieving with a pressure operable device negative pressure below the first level of negative pressure created in the fuel tank,

wherein the pressure operable device is actuated with a solenoid.

7. The method according to claim 6, further comprising:

relieving with the pressure operable device positive pressure created in the fuel tank.

8. The method according to claim 6, wherein the switch and the pressure operable device are integrated into a common housing.