Month in the Patent Office

A valve, which is opened by the operation of the engine, prevents delivery of fuel from a throttle‐actuated accelerator pump to the induction system, when the engine is not running. During operation of the engine, the lubricating‐oil pressure acting on a spring‐pressed piston 46 moves a control valve, formed by a stem 41 having enlarged parts 44, 45 into the position shown in Fig. 1, to permit the fuel discharged by the pump piston 10 to be delivered through a conduit 30 to a fuel nozzle 32. When the engine stops, the oil pressure falls and the spring 50 moves the piston 46 to the left until it engages an abutment 51. In this position, the enlarged part 45 closes the conduit 30, and the enlarged part 44 uncovers a conduit 40 connected to the float chamber 15 so that if the throttle is now opened, the fuel discharged by the pump is returned to the float chamber. The piston 46 may be replaced by a diaphragm and may be operated by the suction, or in a supercharged engine by the pressure, in the induction system. The provisional Specification states that the control valve may be disposed between the float chamber and the pump.