Diesel fuel injection pump fuel injection cutoff upon detection of

Abstract

A fuel injection pump for a diesel engine includes a means for calculating a proper fuel injection amount per each engine stroke and a means for injecting an amount of fuel per each engine stroke approximately equal to this proper fuel injection amount determined by this injection amount calculating means. The pump also includes a means for calculating a reference combustion time which represents approximately how long combustion in an engine stroke should last, and a means for detecting the approximate start and end of combustion in that engine stroke. From this information, these, an appropriate means calculates the approximate actual time of combustion in that engine stroke, and then another means compares the thus calculated approximate actual combustion time and the thus calculated reference combustion time, and based upon the result of said comparison selectively actuates a means for cutting off fuel injection, so as to stop the diesel engine from running and so as thereby to prevent overrunning due to abnormal combustion, if it decides as a result of the comparison that the actual combustion time is too long as compared with the reference combustion time. Optionally, this comparison may consider whether or not the calculated approximate actual combustion time has been greater than the calculated reference combustion time for a specified number of consecutive combustion cycles, and may interrupt engine running if such has been the case.