Roll-over valve and vapor separator

• US 3,937,198 A
• Filed: 01/24/1974
• Issued: 02/10/1976
• Est. Priority Date: 01/24/1974
• Status: Expired due to Term

• Current Assignee: Chrysler Corporation (Stellantis NV)
• Original Assignee: Chrysler Corporation (Stellantis NV)
• Inventors: Sudhir, Gopinath
• Primary Examiner(s): Myhre, Charles J.
• Assistant Examiner(s): Argenbright, Tony
• Application Number:
  US05/436,287
• Time in Patent Office: 747 Days
• Field of Search: 123/136, 123/120
• US Class Current: 123/519
• 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

A vacuum controlled valve either in series or parallel with the customary bleed orifice in the vapor flow path from the fuel tank to the charcoal canister of an automobile evaporative control system opens when the engine is operating to direct fuel vapor flow from the tank to the fuel-air inlet induction conduit, thereby to prevent excessive fuel vapor pressure in the tank that would otherwise be released to the atmosphere via the customary pressure vented closure cap for the fuel tank filler spout.

Claims

1. In an automobile engine having a fuel tank and an intake manifold for supplying fuel and air to said engine, the combination of vapor storage means, vent conduit means for venting fuel vapors to said storage means from said tank, said vent conduit means including bypass conduit means for providing a restricted vapor flow path bypassing said storage means, control means for controlling vapor flow through said vent conduit means from said tank comprising valve means in said bypass conduit means movable between open and closed positions, means for normally moving said valve means to said closed position to close said bypass conduit means, and pressure actuated means responsive only to a predetermined, sub-atmospheric pressure in said intake manifold and a simultaneous vapor pressure in said tank greater than a predetermined comparatively low pressure above atmospheric for moving said valve means to open said bypass conduit means to establish communication therethrough between said tank and intake manifold.

2. In the combination according to claim 1, bleed means comprising a restricted orifice in said vent conduit means bypassing said valve means for providing a restricted flow path for said vapors when said bypass conduit means is closed by said valve means.

3. In the combination according to claim 2, said vapor storage means having an air inlet in communication with the atmosphere and also having a purge outlet, and means for purging fuel vapors from said storage means comprising purge conduit means for connecting said purge outlet with sub-atmospheric pressure of said intake manifold for inducing gas flow through said vapor storage means from said inlet to said outlet and into said intake manifold when said engine is operating.

4. In the combination according to claim 1, said valve means comprising first valve means cooperable with said pressure actuated means to be moved to its open position thereby in response to said predetermined sub-atmospheric pressure and also comprising second valve means cooperable with the first valve means for normally closing said bypass conduit means when at least one of said valve means is closed and being cooperable with said pressure actuated means to be moved to its open position thereby in response to said simultaneous vapor pressure, to establish communication between said tank and said intake manifold through said bypass conduit means when both valve means are open.

5. In the combination according to claim 1, said vent conduit means comprising a first conduit means in communication with said storage means for venting fuel vapor thereto from said tank and a second conduit means comprising said bypass conduit means, said first conduit means having restricting means for restricting the same to limit the rate of vapor flow from said tank to said storage means.

6. In the combination according to claim 5, means for purging said storage means of fuel vapor stored therein comprising an air inlet in communication with the atmosphere and a purge outlet in communication with said manifold for inducing air flow through said storage means from said air inlet to said purge outlet and thence into said intake manifold during operation of said engine.

7. In the combination according to claim 4, said second valve means comprising a pressure chamber having an inlet port and an outlet port and, defining portions of said bypass conduit means, movable means defining a movable wall portion of said chamber and having a valve element normally closing one of said ports, said movable means being responsive to vapor pressure in said tank in excess of a predetermined small value above atmospheric for moving said valve element to open said one port to establish comunication in said bypass conduit through said chamber.

8. In the combination according to claim 7, said chamber being in communication with said tank via said inlet port, and said one port normally closed by said valve element comprising said outlet port.

9. In the combination according to claim 7, said movable wall portion exteriorly of said chamber being in restricted communication with the atmosphere.

10. In the combination according to claim 9, said vent conduit means comprising a first conduit means in communication with said tank and storage means for venting fuel vapor to the latter from said tank and a second conduit means comprising said bypass conduit means, one-way check valve means normally closing said first conduit means and responsive to a predetermined small pressure in said tank above atmospheric for opening said first conduit means, and bleed means for providing a restricted rate of vapor flow through said first conduit means from said tank to said storage means.