초록 ▼

This device diagnoses whether or not a fuel pump which supplies fuel to an engine has failed. The pump includes a plurality of pressure chambers which in turn discharge fuel according to the rotation of an input shaft which turns together with the engine. The supply capacity of the fuel pump when on

This device diagnoses whether or not a fuel pump which supplies fuel to an engine has failed. The pump includes a plurality of pressure chambers which in turn discharge fuel according to the rotation of an input shaft which turns together with the engine. The supply capacity of the fuel pump when one of the pressure chambers has failed so as not to be able to discharge fuel is set to a value lower than the maximum value of the fuel supply amount which is required by the engine. A mechanism is provided which decides whether or not the fuel supply requirement of the engine is being satisfied, and failure of the fuel pump is diagnosed based upon the result of this decision. Further, accurate diagnosis can be performed by detecting the power output of the engine for each cylinder individually, and by deciding upon fuel supply insufficiency for each cylinder individually according to variation of the output power for each cylinder individually.

대표청구항 ▼

[ The embodiment of this invention in which an exclusive property or privilege is claimed are defined as follows:] [1.] A failure diagnosis device for a fuel pump, said pump having a plurality of pressure chambers that, according to a rotation of an input shaft which turns together with an engine, i

[ The embodiment of this invention in which an exclusive property or privilege is claimed are defined as follows:] [1.] A failure diagnosis device for a fuel pump, said pump having a plurality of pressure chambers that, according to a rotation of an input shaft which turns together with an engine, in turn discharge fuel which is supplied to said engine, wherein a fuel supply capacity of said pump is set to be lower, when one of said pressure chambers has a failure so as not to be able to discharge fuel, than a maximum value of a fuel supply amount which is required by said engine, comprising:means for determining whether or not a fuel supply requirement of said engine is satisfied, andmeans for diagnosing that said pump has a failure when said fuel supply requirement is not satisfied.