Engine runaway preventing safety means associated with a distributor-type fuel injection pump

Claim 1

In a fuel injection pump delivering metered fuel to an internal combustion engine and being of the type that has (a) a distributor shaft, (b) a pump work chamber defined within said distributor shaft, (c) piston means operating in said pump work chamber, (d) a rotary component driven by said engine with an rpm that is a function of the engine rpm, (e) a movable control throttle for determining, as a function of its position, the fuel quantities to be injected, (f) rotary electromagnet means coupled to said control throttle to position the same in response to electric signals applied to said rotary electromagnet means, the improvement comprising A. a discharge channel formed as a longitudinal bore in said distributor shaft and connected to said pump work chamber, B. a movable valve member adapted to assume a first position obturating said discharge channel and a second position opening said discharge channel for depressurizing said pump work chamber and C. centrifugal means mounted to said distributor shaft and including said movable valve member for moving the latter into said second position beyond a predetermined rpm, said distributor shaft being in turn coupled to said rotary component.