Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
245 words
A hydrocarbon recovery and pressure control system comprising: a valve adapted to communicate between a source of hydrocarbons, a hydrocarbon storage unit and a source of vacuum pressure, said valve responsive to and adapted to receive control signals and said valve comprising: first passage means for communicating hydrocarbons from the source thereof to the storage unit, including a first valve seat; second passage means for communicating hydrocarbons from the storage unit to the vacuum pressure source, including a second valve seat; a solenoid assembly disposed between said first passage means and said second passage means; a central member, means for separating said central member into a first chamber proximate said first valve seat and a second chamber proximate said second valve seat, a first piston slidably received in said central member at said first chamber and first means for biasing said first piston into sealing engagement upon said first valve seat, a second piston slidably received in said central member, at said second chamber and second means for biasing said second piston into sealing engagement upon said second valve seat; said first piston operable to move against the bias force generated by said first biasing means at a first value of said control signal to permit communication through said first valve seat; and said second piston operable to move against the bias force generated by said second biasing means at a second value of said control signal to permit communication through said second valve seat.
Claim 2
Dependent Claim
245 words
A hydrocarbon recovery and pressure control system comprising: a valve adapted to communicate between a source of hydrocarbons, a hydrocarbon storage unit and a source of vacuum pressure, said valve responsive to and adapted to receive control signals and said valve comprising: first passage means for communicating hydrocarbons from the source thereof to the storage unit, including a first valve seat; second passage means for communicating hydrocarbons from the storage unit to the vacuum pressure source, including a second valve seat; a solenoid assembly disposed between said first passage means and said second passage means; a central member, means for separating said central member into a first chamber proximate said first valve seat and a second chamber proximate said second valve seat, a first piston slidably received in said central member at said first chamber and first means for biasing said first piston into sealing engagement upon said first valve seat, a second piston slidably received in said central member, at said second chamber and second means for biasing said second piston into sealing engagement upon said second valve seat; said first piston operable to move against the bias force generated by said first biasing means at a first value of said control signal to permit communication through said first valve seat; and said second piston operable to move against the bias force generated by said second biasing means at a second value of said control signal to permit communication through said second valve seat.
Claim 3
Dependent Claim
38 words
The system as defined in claim 1 wherein said first and second biasing means comprise first and second springs and wherein the spring constant of said first spring is less than the spring constant of said second spring.
Claim 4
Dependent Claim
16 words
The system as defined in claim 2 wherein said first and second pistons are axially aligned.
Claim 5
Dependent Claim
45 words
The system as defined in claim 2 wherein said first passage means includes a by-pass passage for communicating fluid about said first valve seat, a pressure responsive valve within said by-pass passage responsive to a pressure differential thereacross for opening and closing said by-pass passage.
Claim 6
Dependent Claim
28 words
The system as defined in claim 4 wherein said pressure responsive valve is operable to permit communication through said by-pass in response to a predetermined vacuum pressure differential.
Claim 7
Dependent Claim
26 words
The system as defined in claim 5 wherein said first piston is movable off from said first valve when the pressure thereacross exceeds a predetermined level.
Claim 8
Dependent Claim
30 words
The system as defined in claim 6 wherein said pressure responsive valve opens when the differential vacuum pressure between said hydrocarbon source and said storage unit exceeds said predetermined differential.
Claim 9
Dependent Claim
22 words
The system as defined in claim 1 wherein said means for separating includes a stator or core positioned within said central member.
Claim 10
Dependent Claim
16 words
The system as defined in claim 5 wherein said pressure responsive valve is an umbrella valve.
Claim 11
Dependent Claim
27 words
The system as defined in claim 5 further including another pressure responsive valve in said by-pass means for opening said by-pass means at a predetermined pressure level.
Claim 12
Dependent Claim
33 words
The system as defined in claim 1 wherein said source of hydrocarbons is a fuel take, said storage unit is a charcoal canister and said vacuum pressure source is engine intake manifold pressure.