Methods and systems are provided for regulating the flow of fuel vapors exiting a fuel tank. In one example, a method for an engine may include adjusting an amount of fuel vapors flowing through a fuel vapor recirculation line, where the recirculation line may be coupled on a first end to a fuel tank and on an opposite second end to a fuel fill inlet. The valve may be adjusted to a more open position to increase fuel vapor flow through the recirculation line in response to increases in hydrocarbon emissions from a fuel vapor canister, and to a more closed position to reduce fuel vapor flow through the recirculation line in response to increases in hydrocarbon emissions from the fuel fill inlet.

An isolation valve includes a flow restrictor in a passage and having an orifice and configured to provide a first, second, and third flow paths. A spring may bias the flow restrictor to an open position that opens the second flow path. A solenoid assembly may include a coil and an armature moveable between an extended position that moves the flow restrictor to close the first, second, and third flow paths, and a retracted position that opens the first flow path. The first flow path may include a path from a first reservoir through the orifice to a second reservoir. The second flow path may include a first flow direction from the first reservoir to the second reservoir via a second path, the second path including a space between the flow restrictor and the passage. The third flow path may include a second flow direction from the second reservoir to the first reservoir via the second path.

A valve device includes a valve seat forming member, a case, a first O-ring, and a second O-ring. The valve seat forming member is fit into a passage defining and forms a valve seat. The case houses an electromagnetic solenoid and is connected to the passage defining member. The first O-ring is interposed between an inner circumferential surface of the passage defining member and an outer circumferential surface of the valve seat forming member. The first O-ring prohibits the fluid from flowing through a space between the passage defining member and the valve seat forming member when the main valve body seats on the valve seat. The second O-ring is interposed between the case and the passage defining member. The second O-ring prohibits the fluid from flowing from the passage to an outside of the passage defining member.

A first valve chamber, which receives a valve assembly of a tank closing solenoid valve, and a second valve chamber, which receives a valve assembly of a pressure responsive valve, are formed between a first flow passage and a second flow passage of a first housing by fitting a second peripheral wall of a second housing into a radially inner side of a first peripheral wall of the first housing. Thereby, it is not required to heat-weld and bond between a connecting end surface of the first housing and a connecting end surface of the second housing.

A vehicle fuel system is provided that includes a fuel tank and a manual vent system. The manual vent system includes an emergency valve and an actuator. The manual vent system is configured to cause the emergency valve to open after the actuator has been actuated.

A fuel vapor processing apparatus includes an adsorbent canister, a vapor path connecting the adsorbent canister to a fuel tank, and a flow control valve disposed in the vapor path. The flow control valve is kept closed while a movement distance of a valve body from a predetermined initial position toward a valve opening direction is less than a predetermined distance. A control unit comprising part of the apparatus is configured to set a valve opening speed of the flow control valve to a first speed under a condition where the movement distance of the valve body is less than the predetermined distance, and to set the valve opening speed of the flow control valve to a second speed lower than the first speed under a condition where the movement distance of the valve body is greater than the predetermined distance.

An evaporative fuel treatment apparatus, which is loaded on a hybrid vehicle equipped with a fuel tank and a battery mounted forward of the fuel tank, has a sealing valve for sealing evaporative fuel in the fuel tank. The sealing valve is disposed between the battery and the fuel tank and is arranged above the battery. The evaporative fuel treatment apparatus can prevent fuel leakage from the sealing valve more reliably.

A fuel filling apparatus and method for a bi-fuel vehicle using both gasoline and liquefied petroleum gas (LPG) as a fuel are provided to. The fuel filling apparatus and method are capable of temporarily burning a portion of LPG fuel after collecting the fuel portion, using a gasoline fuel tank and a canister, when the internal pressure of an LPG fuel tank in the bi-fuel vehicle is equal to or greater than an LPG filling pressure of a filling gun. Additionally, the internal pressure of the LPG fuel tank is decreased to a level below the LPG filling pressure of the filling gun, thereby achieving smoother LPG fuel filling of the LPG fuel tank by the filling gun.

A filter arrangement includes an activated carbon filter, a fuel tank, an engine, at least one of an air filter or a dust filter, and at least one valve. The at least one valve is configured to allow fresh air to flow through the activated carbon filter in order to regenerate the carbon filter. The activated carbon filter is at least one of associated with the intake tract of the engine, integrated into the intake tract of the engine; or a component of a modular unit with the intake tract of the engine.

A fuel shutoff valve is attached to the upper portion of a fuel tank and shuts off the communication between the inside of the fuel tank and a canister by opening and closing a vapor passage for communicating between the fuel tank and the canister. The fuel shutoff valve is configured with a first valve mechanism having a coil disposed on the inner periphery of a cylindrical valve chamber and a movable core, which enables to communicate between the fuel tank and the canister by lowering the level of the movable core, and a second valve mechanism which enables to communicate between the fuel tank and the outside thereof by shifting the level of the valve body which is disposed inside the movable core due to the pressure from the inside of the fuel tank or the outside thereof.