High pressure valve for hydrogen gas and decompression device for hydrogen gas

Abstract

A high pressure valve for hydrogen gas includes a valve seat and a valve member, which is movable to selectively open and close the valve seat. One of the valve member and the valve seat is formed of austenitic stainless steel, and the other one of the valve member and the valve seat is formed of flexible synthetic resin or soft metal.

1 . A high pressure valve for hydrogen gas, the high pressure valve comprising a valve seat and a valve member, which valve member is movable to selectively open and close the valve seat, and 
 one of the valve member and the valve seat is formed of austenitic stainless steel, and the other one of the valve member and the valve seat is formed of flexible synthetic resin or soft metal.    
     
     
         2 . The high pressure valve for hydrogen gas according to  claim 1 , wherein the synthetic resin is selected from the group consisting of polyimide resin, polyether ether ketone resin, and polyfluoroethylene resin.  
     
     
         3 . The high pressure valve for hydrogen gas according to  claim 2 , wherein the polyimide resin is VESPEL.  
     
     
         4 . The high pressure valve for hydrogen gas according to  claim 1 , wherein the surface roughness of the valve seat and the valve member is less than or equal to 1 μmRa.  
     
     
         5 . The high pressure valve for hydrogen according to  claim 1 , further comprising an accommodating member in which the valve member is located to freely slide in the accommodating member, and 
 wherein a coating is formed on the surface of the valve member to reduce friction between the valve member and the accommodating member.    
     
     
         6 . The high pressure valve for hydrogen gas according to  claim 5 , wherein the coating is formed through any one of a treatment of physical vapor deposition coating, baking, and plating.  
     
     
         7 . The high pressure valve for hydrogen gas according to  claim 5 , wherein the coating is selected from the group consisting of a diamond-like carbon coating, CrN coating, TiN coating, Au coating, MOS 2 -coating, polytetrafluoroethylene coating, Ni—P plating, and Ni—B plating.  
     
     
         8 . A high pressure valve for hydrogen gas, the high pressure valve comprising: 
 a solenoid;    a main valve seat and a pilot valve seat;    a main valve body, which is switchable between a closed state, where the main valve body contacts the main valve seat, and an open state, where the main valve body is separated from the main valve seat; and    a pilot valve body, which is switchable between a closed state, where the pilot valve body contacts the pilot valve seat, and an open state, where the pilot valve body is separated from the pilot valve seat,    wherein the pilot valve body is switched between the open state and the closed state in accordance with excitation and de-excitation of the solenoid, and the main valve body switches from the closed state to the open state when the pilot valve body is switched from the closed state to the open state.    
     
     
         9 . The high pressure valve according to  claim 8 , further comprising: 
 a plunger, which operates in accordance with excitation and de-excitation of the solenoid, wherein the plunger is coupled to the pilot valve body and the main valve body, the main valve body includes a pilot bore and the pilot valve seat, the pilot valve seat includes a pilot valve hole, which is connected to the pilot bore, at least one of the pilot valve body and the main valve body is supported with respect to the plunger to have play in the operational direction of the plunger, when the pilot valve body contacts the pilot valve seat, the pilot valve hole and the pilot bore are closed.    
     
     
         10 . The high pressure valve according to  claim 9 , wherein the pilot valve body includes a distal end having an outer diameter that decreases toward the pilot valve seat, and the pilot valve hole of the pilot valve seat includes an inner diameter that is set in accordance with the outer diameter of the distal end of the pilot valve body.  
     
     
         11 . The high pressure valve according to  claim 9 , wherein the pilot valve seat includes a projection having a distal end surface, the pilot valve hole opens at the distal end surface of the projection, and the pilot valve body includes a flat surface, which selectively contacts the distal end surface of the projection, and when the flat surface contacts the distal end surface of the projection, the pilot valve hole is closed.  
     
     
         12 . A pressure reducing valve used to reduce the pressure in a tank containing hydrogen gas, the pressure reducing valve comprising: 
 a valve body and a diaphragm, wherein the valve body and the diaphragm define a pressure reducing chamber, the pressure reducing chamber including a valve hole provided with a valve seat; and    a valve member located to selectively contact the valve seat, wherein the valve member is connected to the diaphragm, and the diaphragm is displaced in accordance with the pressure in the pressure reducing chamber, and the valve member selectively opens and closes the valve hole in accordance with the displacement of the diaphragm.    
     
     
         13 . The pressure reducing valve according to  claim 12 , further comprising: 
 an accommodating member, which includes the valve hole and accommodates the valve member, wherein a sealless portion is set between the accommodating member and the valve member.    
     
     
         14 . A decompression device for connection to a high pressure hydrogen tank, the decompression device comprising an electromagnetic valve connectable to the high pressure hydrogen tank and a pressure reducing valve connected to the electromagnetic valve for emitting decompressed hydrogen gas to the exterior via the electromagnetic valve and the pressure reducing valve, the electromagnetic valve including: 
 a solenoid;    a main valve seat and a pilot valve seat;    a main valve body, which is switchable between a closed state, where the main valve body contacts the main valve seat, and an open state, where the main valve body is separated from the main valve seat; and    a pilot valve body, which is switchable between a closed state, where the pilot valve body contacts the pilot valve seat, and an open state, where the pilot valve body is separated from the pilot valve seat,    wherein the pilot valve body is switched between the open state and the closed state in accordance with excitation and de-excitation of the solenoid, and the main valve body switches from the closed state to the open state when the pilot valve body is switched from the closed state to the open state,    the pressure reducing valve including:    a valve body and a diaphragm, wherein the valve body and the diaphragm define a pressure reducing chamber, the pressure reducing chamber including a valve hole provided with a valve seat, and a valve member located to selectively contact the valve seat,    wherein the valve member is connected to the diaphragm, and the diaphragm is displaced in accordance with the pressure in the pressure reducing chamber, and the valve member selectively opens and closes the valve hole in accordance with the displacement of the diaphragm.    
     
     
         15 . A high pressure valve for hydrogen gas, the high pressure valve comprising a valve seat and a valve member, which valve member is movable to selectively open and close the valve seat, 
 the valve member and the valve seat each having a contact portion, which contact portions contact each other, one of the contact portion of the valve member and the contact portion of the valve seat being formed of austenitic stainless steel, and the other one of the contact portion of the valve member and the contact portion of the valve seat being formed of flexible synthetic resin or soft metal.