Purge flow control valve

Patent · Tue Nov 03 04:00:00 EST 1987

OSTI ID:5803837

De Minco, C M; Field, M J; Serth, D E

This patent describes a valve for controlling purge of fuel vapor to an engine having an induction passage for air flow to the engine and a throttle in the induction passage rotatable between closed and open positions for controlling air flow therethrough. The valve comprises a housing having an inlet for fuel vapor, a valve seat surrounding the inlet, a primary outlet to the induction passage downstream of the throttle, an orifice restricting flow through the primary outlet, a secondary outlet to the induction passage at a location upstream of the throttle when the throttle is in the closed position and downstream of the throttle when the throttle is in the open position and a valve member in the housing. The valve member has a head engageable with the valve seat to obstruct flow through the housing. The valve member further has a metering section receivable in the orifice for varying the flow restriction of the orifice, and a spring biasing the valve member to engage the head with the valve seat. The valve member is movable against the bias of the spring in response to the subatmospheric pressure in the induction passage downstream of the throttle to disengage the head from the valve seat and to cause the metering section to vary the flow restriction of the orifice in accordance with variations in the pressure, whereby flow of fuel vapor through the inlet to the induction passage is obstructed when the engine is not operating, flow of fuel vapor through the inlet to the induction passage is limited to the primary outlet when the engine is operating and the throttle is in the closed position, and flow of fuel vapor through the inlet to the induction passage is permitted through both the primary outlet and the secondary outlet when the engine is operating and the throttle is not in the closed position.

• Assignee: General Motors Corp., Detroit, MI
• Patent Number(s): US 4703738
• OSTI ID: 5803837
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
AIR FLOW
CONTROL EQUIPMENT
DESIGN
ENGINES
EQUIPMENT
FLOW REGULATORS
FLUID FLOW
FLUIDS
FUEL INJECTION SYSTEMS
FUEL SYSTEMS
GAS FLOW
GASES
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
OPERATION
PRESSURE DEPENDENCE
VALVES
VAPORS