Regulator for fuel cell

A regulator for use with fuel cells, comprising:

• a body having a primary port for being supplied with a fuel gas and a secondary port for discharging the fuel gas;
• a valve head displaceably disposed in said body for being unseated from and seated on a valve seat for opening and closing a fluid passage which interconnects said primary port and said secondary port;
• a first diaphragm and a second diaphragm which are disposed in said body and spaced a predetermined distance from each other, said first diaphragm being flexible under the pressure of pilot air as an oxidizing agent supplied to a pilot chamber, said second diaphragm being flexible under the pressure of the fuel gas flowing through said fluid passage;
• a rod for displacing said valve head, said first diaphragm, and said second diaphragm in unison with each other upon flexing of said first and second diaphragms;
• a first spring engaging said valve head for normally urging said valve head in a direction to be seated on said valve seat;
• and
• a second spring disposed in said pilot chamber for normally urging said valve head in a direction to move away from said valve seat;
• wherein the spring force of said first spring is set to a value greater than the spring force of said second spring, and said valve head is seated on said valve seat when the pilot air is not supplied to said pilot chamber.