Fuel cell systems that use a fuel gas such as hydrogen and an oxidizing gas such as air to generate electricity are well known. These fuel cell systems are used, for example, by mounting in a vehicle or the like as the power source for a motor used for driving the vehicle. Of course, fuel cell systems can also be used for applications other than vehicles.
A fuel cell system comprises a fuel cell that generates electricity by reacting a fuel gas with an oxidizing gas, and a fluid flow path that supplies the reactant gases, namely the fuel gas and the oxidizing gas, to the fuel cell, and discharges the reacted gases and generated water and the like from the fuel cell.
In this type of fuel cell system, a multitude of technologies have been proposed relating to the valves provided within the fluid flow path.
For example, Patent Document 1 (JP 2004-6166 A) discloses a technique for sealing a reactant gas space inside a fuel cell, by providing an opening and closing valve in each of the reactant gas supply lines and discharge lines, and closing these opening and closing valves when electric power generation by the fuel cell is stopped.
Furthermore, Patent Document 2 (JP 2000-3717 A) discloses a technique for controlling the cut-off of a gas or the like supplied to a fuel cell, by supplying air from an air compressor to control an air pilot valve.
USPTO Backgrounds
USPTO Backgrounds