automatic device for opening and chiusupa of orifices of entry and exit of fuel, a fuel budget

摘要

1527247 Control of oxidant supply to fuel cell INSTITUT FRANCAIS DU PETROLE 7 Oct 1975 [8 Oct 1974] 41102/75 Heading H1B A fuel cell has inlet and outlet ports connected to an electrolyte feeding circuit including a pump for electrolyte circulation, and inlet and outlet ports for oxidant with valve means for opening and closing these, and control means connected to the valve means and adapted to open and close them in response to flow conditions in the electrolyte circuit; this facilitates start-up and shut down of the cell, in that oxidant can only be supplied when there is electrolyte flow in the cell, thus preventing accidental damage to the electrodes. In one embodiment, the valve means are electrically controlled valves; a pressure sensitive switch downstream of the pump in the electrolyte circuit serves to open the valves when electrolyte is flowing, and close them when it ceases to flow. Alternatively, a generator coupled directly to the motor which drives the electrolyte pump may supply the signal to open and close the valves. In another embodiment, part of the electrolyte flow tube is vertical and transparent, with an opaque ball in the transparent part, and a light source and photo-cell either side thereof, so that when electrolyte flow causes the ball to rise, light reaches the photo-cell thereby generating a signal to open valves in the oxidant line; on stopping the electrolyte flow the ball falls and blocks the light to the photo-cell, thus closing the valves. In Fig. 5, the valve means comprise a valve 31 with seat 32; electrolyte pressure downstream of pump P causes deformation of membrane 37 against the effect of spring 38 to open the valve; on cessation of electrolyte flow spring 38 closes the valve. Fig. 6 (not shown) shows a similar arrangement, but which uses the pressure difference between the upstream and downstream ends of the pump.