A fluid tank comprising can include an outer housing comprising a housing volume, a first fluid bladder positioned within the housing volume, and a second fluid bladder positioned within the housing volume. The first fluid bladder can comprise a first conduit and the second fluid bladder can comprise a second conduit. The first fluid bladder can be configured to release fluid through the first conduit in response to introduction of fluid into the second fluid bladder via the second conduit. The housing volume can be maintained at a substantially constant pressure when fluid is released from the first fluid bladder through the first conduit and fluid is introduced into the second fluid bladder through the second conduit.

There is provided a valve device including: a housing; a float valve; and a pressure adjusting valve. A first valve seat is formed from a peripheral edge of a valve hole. An accommodation portion is provided in a protruding manner from a surface of a partition wall. An inner periphery of the accommodation portion is provided with a reduced diameter portion and an increased diameter portion. A height of an upper end of the reduced diameter portion is equal to or greater than a front surface of the pressure adjusting valve in a state where the pressure adjusting valve is in contact with the first valve seat. The pressure adjusting valve is configured to be beyond the upper end of the reduced diameter portion when the pressure adjusting valve is raised to a maximum due to an increase in pressure in a fuel tank.

There is provided a valve device including: a housing in which a valve chamber is provided on a lower side and a ventilation chamber is provided on an upper side via a partition wall, the partition wall being formed with a valve hole; a float valve; and a pressure adjusting valve. An accommodation portion is provided in a protruding manner from a surface of the partition wall. An accommodating space configured to accommodate the pressure adjusting valve is formed on an inner side of the accommodation portion, and an outer space is formed on an outer side of the accommodating space. The accommodation portion is formed with an opening through which the accommodating space and the outer space communicate with each other.

A fuel storage device includes a fuel tank, a circulation passage, a canister, a vapor passage, and an adjuster. The fuel tank is configured to store fuel. The circulation passage fluidly connects the fuel tank and a vicinity of a fuel supply port. The canister is configured to recover gas generated in the fuel tank. The vapor passage fluidly connects the fuel tank and the canister. The adjuster is configured to adjust a circulation flow rate of the gas flowing through the circulation passage in supply of the fuel, using a negative pressure.

A fluid vent valve (1) for a fuel tank, comprising: a valve body (10) having an inlet opening connected or connectable to a tank, an outlet opening and a main chamber (13) interposed between said inlet opening and said outlet opening (12); a piston (20) inserted or insertable in the main chamber (13) and movable therein so as to define a closed configuration and an open configuration; a pendulum (30) hinged to the valve body (10) and coupled to the piston (20) so as to promote a movement of the piston (20) between the two configurations; a flow reducer (40) operatively interposed between the outlet opening (12) and the piston (20).

A vent shut-off assembly configured to manage venting on a fuel tank includes a main housing, a poppet valve and an actuator. The main housing is positioned outside of the fuel tank and selectively vents to a canister. The poppet valve is disposed in the main housing and includes a plunger that provides over pressure relief (OPR) and over vacuum relief (OVR) functions. The actuator assembly can be housed in the main housing and includes a cam assembly having a cam shaft that includes a cam having a profile that one of opens and closes the poppet valve. When the poppet valve is in the closed position, vapor is precluded from passing between the fuel tank and the canister. When the poppet vale is in the open position, vapor is permitted from passing between the fuel tank and the canister.

A fuel tank isolation valve for a vehicle is provided. A valve opening operation or a valve closing operation is performed using guide protrusions configured to move along a guide slot, in response to an upward or downward movement of a plunger. The discharge of a battery is prevented. An abrupt change in the pressure of a fuel tank is prevented.

A fuel tank structure that makes it difficult for mud, water, dust or the like to enter a fuel tank and that can restrict a fuel leakage path when a vehicle falls. A fuel cap includes a cap body mounted to a fuel supply port of a fuel tank, and a pressure adjusting device provided in the cap body to adjust a pressure in the fuel tank. In the fuel cap, a space is formed as a hermetically closed space in which the pressure adjusting device is accommodated, and the space communicates with an exterior of the fuel tank via a breather tube.

A fuel supply valve for supplying fuel from a fuel tank to a fuel cell stack includes: a plunger having a hollow therein, a core part disposed on the plunger, and a block part disposed within the hollow to maintain airtightness between the core part and the plunger, and a space in which the airtightness of the hollow has been maintained by the plunger, the core part, and the block part is defined as a pressure chamber.

A fuel tank unit may include a fuel tank, a canister configured to adsorb and desorb vapor generated in the fuel tank, a vapor conduit communicating the fuel tank with the canister, and a full tank fuel level limiting valve device connected to a fuel tank-side end of the vapor conduit. The full tank fuel level limiting valve device includes a full tank fuel level limiting valve and an actuator. The full tank fuel level limiting valve includes a float that is configured to float due to a buoyancy force of fuel in the fuel tank so as to close the full tank fuel level limiting valve when the fuel tank is filled up. The actuator includes a valve closure prevention member that is configured to move and press the float when the actuator is activated, so as to prevent the float from moving in a valve closing direction.