Onboard vapor recovery system with two-stage shutoff valve

• US 5,590,697 A
• Filed: 08/24/1994
• Issued: 01/07/1997
• Est. Priority Date: 08/24/1994
• Status: Expired due to Fees

• Current Assignee: GT Products, Inc. (Eaton Corporation PLC.)
• Original Assignee: GT Products, Inc. (Eaton Corporation PLC.)
• Inventors: Benjey, Robert P., Bergsma, Rudolph
• Primary Examiner(s): JACYNA, J CASIMER
• Application Number:
  US08/295,196
• Time in Patent Office: 867 Days
• Field of Search: 141/44-46, 141/52, 141/53, 141/59, 141/128, 141/192, 141/198, 141/302-304, 137/43, 137/202, 137/587, 220/86.2, 220/86.3
• US Class Current: 141/59
• CPC Class Codes: B60K 15/03519 Valve arrangements in the vent line
• CPC Class Codes: B60K 15/04 Tank inlets B60K15/077 takes precedence
• CPC Class Codes: B60K 2015/03561 Venting means working at specific times
• CPC Class Codes: B60K 2015/03576 Venting during filling the reservoir
• CPC Class Codes: F16K 17/36 actuated in consequence of extraneous circumstances, e.g. shock, change of position
• CPC Class Codes: F16K 17/366 the closure member being a movable ball F16K17/38 takes precedence
• CPC Class Codes: F16K 24/042 actuated by a float
• CPC Class Codes: F16K 24/044 the float being rigidly connected to the valve element, the assembly of float and valve element following a substantially translational movement when actuated, e.g. also for actuating a pilot valve
• CPC Class Codes: Y10T 137/0874 Vent opening or closing on tipping container
• CPC Class Codes: Y10T 137/3099 Float responsive

Abstract

An onboard vapor recovery system for a vehicle fuel system having a fuel tank, a filler neck dynamically sealed by high pressure fuel flow from a filler nozzle, and a vapor recovery apparatus such as a carbon canister. The system includes a liquid level operated control valve which shuts off refueling with a two-stage closing operation providing an initial soft shutoff and a final shutoff. The system also preferably includes a valve in the fuel tank to maintain a predetermined pressure head sufficient to hold the system closed against further refueling at least temporarily, and a positive action, one-way check valve in the lower end of the filler pipe to prevent spitback of fuel from the pressurized tank once refueling has ceased.

Claims

1. In a vehicle fuel system having a fuel tank, a dynamically-sealed filler pipe, and onboard vapor recovery apparatus such as a vapor canister, a fuel vapor venting control system comprising:

control valve means in the fuel tank for venting fuel vapor from the tank to the canister at a first higher rate when the fuel level is below a first level, at a second lower rate when the fuel level reaches the first level, and for closing when a second higher level is reached;

valve means in the fuel tank for maintaining a pressure head in the tank sufficient to induce filler nozzle shutoff when the control valve means is closed and for selectively venting fuel vapor to the canister independent of the control valve means; and

check valve means in a lower end of the filler pipe to close the filler pipe with respect to the fuel tank between refueling activity;

wherein,

the control valve means comprises two stage coaxial valve means responsive to the level of liquid fuel in the tank, the coaxial valve means comprising a liquid level responsive float means, first and second valve means associated with the float means, and vent outlet means, the float means responsive to liquid fuel reaching the first level to force the first valve means to a position partially closing the vent outlet means, the first valve means being yieldably biased from the second valve means, the float means being responsive to liquid fuel level above the first level to force the second valve means against the bias of the first valve means to fully close the vent outlet means.

2. In a vehicle fuel system having a fuel tank, a dynamically-sealed filler pipe, and onboard vapor recovery apparatus such as a vapor canister, a fuel vapor venting control system comprising:

control valve means in the fuel tank for venting fuel vapor from the tank to the canister at a first higher rate when the fuel level is below a first level, at a second lower rate when the fuel level reaches the first level, and for closing when a second higher level is reached;

head valve means in the fuel tank for selectively venting fuel vapor to the canister at a predetermined pressure head independently of the control valve means; and

check valve means in a lower end of the filler pipe to close the filler pipe with respect to the fuel tank between refueling activity;

wherein,

the check valve means comprises an axially-operated valve element including bias means for holding the valve element against a valve seat opposite the direction of fluid flow into the tank, radial vent means selectively opened by the valve element upon introduction of liquid fuel from the filler pipe into the tank, and means for reducing suction tending to hold the valve element in an open position caused by flow of fuel through the radial vent means, the valve element further including resilient seal means forced against the valve seat in the closed position by the valve element, and shoulder means on the valve element associated with the resilient seal means to limit the force exerted on the seal means against the valve seat by the valve element.