| 主权项 |
1. An evaporative fuel vapor control system comprising:
a fuel supply for storing fuel that generates fuel vapor in the fuel supply, an internal combustion engine constructed and arranged to be supplied with fuel from the fuel supply, a vapor canister in fluid communication with the fuel supply to retain fuel vapor from the fuel supply, and in fluid communication with the engine, sensor structure comprising:
a body including a sensor portion and an integral tube portion, the tube portion defining a tube having first and second open ends and a passage there-between, one of the ends being fluidly connected with an inlet or an outlet of the canister,a hydrocarbon sensor in the sensor portion and constructed and arranged to determine hydrocarbon concentration of fuel vapor in the tube,a plate having a single, restrictive orifice there-through, the plate being disposed in the tube so that so fuel vapor must pass through the orifice as the fuel vapor moves between the ends of the tube, andpressure transducer structure in the sensor portion and constructed and arranged to determine pressure drop of the fuel vapor across the orifice so as to obtain a flow rate of the fuel vapor through the tube, a vapor control valve fluidly connected with an outlet of the canister and disposed between the engine and the canister, and a controller electrically connected with the sensor structure and with the control valve such that when the controller receives a signal from the sensor structure indicating the hydrocarbon concentration and the flow rate of the fuel vapor in the tube, the controller is constructed and arranged to cause the control valve to control a flow of the fuel vapor to the engine and to control injection valves that inject fuel into the engine, so that an amount of fuel injected into the engine is based on the determined concentration of hydrocarbons in the fuel vapor. |
