Forward check valve and fuel cell system

A forward check valve comprising:

• a valve housing;
• a diaphragm including a peripheral edge portion located on the valve housing;
• a valve body;
• and
• a cap;
• wherein
• the diaphragm and the valve housing are arranged to define a valve chamber;
• a central portion of the diaphragm that is provided at an inner side of a peripheral edge portion is arranged to be displaced by pressure of a fluid in the valve chamber;
• the valve housing includes an inflow hole through which the fluid flows into the valve chamber, an outflow hole connected to a pump and through which the fluid flows out from the valve chamber by suction pressure of the fluid generated by the pump, and a placement portion on which the peripheral edge portion of the diaphragm is located;
• the valve body is disposed at the inflow hole and arranged to block or allow a flow of the fluid into the valve chamber from the inflow hole by displacement of the diaphragm;
• the cap is joined to the valve housing and arranged to push the peripheral edge portion of the diaphragm;
• and
• the peripheral edge portion is sandwiched by the cap and the placement portion.