Abstract: A valve device includes: a valve housing defining a cylindrical space connected to a high-pressure source, and having a first communication hole open at a valve seat located at a bottom portion of the valve housing and providing fluid communication between the cylindrical space and a low-pressure source; a seal member arranged in the cylindrical space and providing or shutting off fluid communication between the high-pressure and low-pressure sources so that the seal member moves away from or contacts the valve seat; and a stem having an accommodating recess at one end of the stem and moved axially. The seal member is fitted and held in the accommodating recess. The seal member has a second communication hole that provides fluid communication between a bottom face of the accommodating recess and the low-pressure source when the seal member is in contact with the valve seat.

Abstract: A fluid supply valve attachment device that has a tank, a fixing member in which a recessed fitting section is formed, a fluid supply valve that is inserted in and fixed to the recessed fitting section, a first seal member which seals a space between the tank and the fixing member, and a second seal member which seals a space between the fixing member and the fluid supply valve. The maximum inside diameter of the recessed fitting section is defined as D, a distance between a cross-sectional center of the first seal member and a cross-sectional center of the second seal member in a direction that a central axial line of the recessed fitting section extends in an attached state is defined as L1, and L1 is set within 2.5×D.

Abstract: A plug body housing 16 has a receiving recess 17 and the receiving recess 17 includes a first recess 21 opening toward the outside and a second recess 22 connected to the first recess 21. Check valves 8 and 9 are provided in the second recess 22, and a manual valve 14 is provided in the first recess 21. An internal threaded portion 45 is formed in an inner circumferential surface of the first recess 21, and a housing 35 of the manual valve 14 is threaded into the internal threaded portion 45. The check valves 8 and 9 are held between a bottom surface 22a of the second recess 22 and a bottom 35a of the housing 35 so that the check valves 8 and 9 are secured in the second recess 22.

Abstract: In a valve device for selectively opening and closing a flow passage formed to open on a valve seat by a valve body through a resin-made seat, a hollow portion is formed on either one of the valve body and the valve seat and receives the resin-made seat therein, the resin-made seat has a thickness so that the resin-made seat partly protrudes from the hollow portion, and when the valve body is operated to close the flow passage, the resin-made seat is compressed to bring an end surface of the valve body into contact with the valve seat.

Abstract: A pressure reducer includes a piston slidably accommodated in a cylinder to define a decompression chamber and a pressure adjusting chamber. A seal member includes an elastic member and a sliding portion. The sliding portion is pressed by the elastic member such that the sliding portion slides on an inner circumferential surface of the cylinder. An annular member is located on an outer circumferential surface of the piston and between the seal member and the pressure adjusting surface. The annular member is pressed against the inner circumferential surface of the cylinder with a force that is less than a force with which the sliding portion is pressed against the inner circumferential surface of the cylinder. Thus, the pressure reducer prevents the piston from being moved by an excessive amount with highly accurately adjusting pressure.

Abstract: A fuel cell system includes a fuel cell (10), a supply passage (11) through which fuel gas and oxidizing gas are supplied to the fuel cell, an exhaust passage (12) through which the fuel gas and the oxidizing gas are discharged from the fuel cell, and a reactor (13) provided in the exhaust passage (12) such that a fuel off-gas from the fuel cell is oxidized. The fuel cell system further includes a bypass passage (14) that extends from the supply passage (11) to reach the reactor (13) and returns to the supply passage (11) such that at least a portion of the fuel gas and the oxidizing gas supplied to the fuel cell upon activation thereof is supplied to the bypass passage 14 and heated in the reactor (13). The bypass passage (14) is communicated with an inside of the reactor (13) such that the gas is heated and humidified under a reaction in the reactor (13) upon activation of the fuel cell.

Abstract: An annular mating portion extends from a fastening surface of a fastening nut. The mating portion has an inner diameter set to be substantially equal to an outer diameter of the portion of a piston in which an accommodating groove is formed. In a state in which the mating portion is inserted into the accommodating groove and an inner circumferential surface of the mating portion slides in contact with a circumferential wall of the accommodating groove, the fastening nut is mated with a threaded portion and a lip seal is held between the mating portion and the accommodating groove. This fixes the lip seal to the piston.

Abstract: A valve device for high-pressure gas opens and closes a communication hole for communicating a primary pressure chamber, into which the high-pressure gas flows, to a secondary pressure chamber where pressure is lower than that of the primary pressure chamber. The valve device has a valve seat member provided at the communication hole and a valve body that is caused to be seated on and to leave from the valve seat member to open and close the communication hole. The communication hole has an opening connected to the primary pressure chamber. The opening has a reception recess opened toward the primary pressure chamber. In the reception recess is fitted the valve seat member. As a result, the valve device can achieve sufficient sealing ability.

Abstract: Provided are an ejector which is capable of linearly controlling an ejection flow rate relative to the amount of movement of a needle to enhance its overall applicability and a fuel cell system with this ejector. The ejector 24 includes a nozzle 46 for ejecting a fluid, a needle 48 disposed coaxial with the nozzle 46 and having a tip end portion 48a which faces the nozzle 46, and needle moving means 49 for causing the needle 48 to advance and retreat axially. The shape of the tip end portion 48a of the needle 48 is set such that the opening area Y of the gap between the tip end portion 48a of the needle 48 and the nozzle 46 and the amount Z of movement produced by the needle moving means 49 satisfy a proportional relationship.