Regulated flow canister purge system
For controlling the purging of a fuel vapor collection canister of an evaporative emission control system associated with the fuel system of an internal combustion engine, a regulated flow canister purge arrangement is described comprising an electronic vacuum regulator having a vacuum inlet at which engine intake manifold vacuum is received, an outlet at which is delivered a percentage of the engine intake manifold vacuum received at the vacuum inlet as determined by an electronic control signal supplied to a control input of the electronic vacuum regulator, a canister purge inlet to which a canister that is to be purged of gaseous fuel vapors is communicated, a canister purge outlet that is communicated to engine intake manifold vacuum, valve means that is operated by a movable wall for controlling flow between the purge inlet and outlet, one side of the movable wall bounding one variable volume chamber and another side of the movable wall bounding another variable volume chamber, a helical coil spring acting on the movable wall so as to cause the valve means to be biased toward blocking flow between the canister purge inlet and the canister purge outlet, means communicating the outlet of the electronic vacuum regulator with the one variable volume chamber to cause the volumes of the chambers to vary in relation to the percentage of manifold vacuum applied to the one variable volume chamber, characterized in that the valve means comprises a valve element that moves with the movable wall and a valve seat circumscribing a passage portion through which purge flow from the canister purge inlet to the canister purge outlet passes, the valve element has a valving portion that telescopically engages the passage portion, and the valving portion and the passage portion have a relative taper by which they co-act to impose on the purge flow a restriction that progressively diminishes as the valve element is operated by the movable wall away from blocking flow.
- Assignee:
- Siemens Automotive Ltd., Chatham, ON (Canada)
- Patent Number(s):
- A; US 5226398
- Application Number:
- PPN: US 7-954517
- OSTI ID:
- 6355481
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
330704* -- Emission Control-- Hydrocarbons
AIR POLLUTION CONTROL
CONTROL
CONTROL EQUIPMENT
DESIGN
ENGINES
EQUIPMENT
EVAPORATION
EXHAUST SYSTEMS
FLOW BLOCKAGE
FLOW REGULATORS
FUELS
GASEOUS WASTES
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
OPERATION
PHASE TRANSFORMATIONS
POLLUTION CONTROL
VACUUM SYSTEMS
VALVES
WASTES