Patent ID: 8676477
Filing Date: 2014-03-18
Classification: F02D,F02N,Y02T

Abstract:
1. A rotational fluctuation malfunction detection device for an internal combustion engine that serves as a power source for a vehicle, the rotational fluctuation malfunction detection device, comprising: a parameter obtaining device that is configured to obtain a value of a fluctuation parameter that indicates a degree of non-uniformity in fluctuation of rotational speed of an output shaft of the internal combustion engine; an automatic engine stop device that is configured to stop the internal combustion engine when an engine stop condition including that the vehicle is stopped is satisfied; and a signal output device that is configured to output a signal that indicates a determination result of whether the degree of non-uniformity of fluctuation of the rotational speed is normal or not based on the value of the fluctuation parameter obtained in the operation of the internal combustion engine, wherein if the value of the fluctuation parameter obtained during a disturbance fluctuation state, in which the rotational speed of the output shaft of the internal combustion engine fluctuates due to disturbances from a driving wheel, is below a first threshold value, the signal output device outputs a signal that indicates the determination result based on the value of the fluctuation parameter obtained in the disturbance fluctuation state, and if the value of the fluctuation parameter obtained in the disturbance fluctuation state equals or exceeds the first threshold value, the signal output device outputs a signal that indicates the determination results based on the value of the fluctuation parameter obtained in a non-disturbance fluctuation state, in which rotational speed of the output shaft of the internal combustion engine does not fluctuate as a result of disturbances from the driving wheel of the vehicle, instead of the value of the fluctuation parameter obtained in the disturbance fluctuation state.