Patent ID: 7343887
Filing Date: 2008-03-18
Classification: F01L,F02D,Y02T

Abstract:
1. An abnormality diagnosis apparatus that diagnoses an abnormality of an adjustable valve mechanism, which varies a moving characteristic of a valve in an internal combustion engine, said abnormality diagnosis device comprising: an input control signal module that inputs a control signal for varying the moving characteristic of the valve; a theoretical value computation module that computes a physical behavior of the adjustable valve mechanism according to a physical model provided to simulate the physical behavior of the adjustable valve mechanism and thereby calculates a theoretical value of a parameter relating to the moving characteristic of the valve, which is varied by the adjustable valve mechanism, based on the input control signal; an observed value detection module that detects an observed value of the parameter relating to the moving characteristic of the valve, which is varied by the adjustable valve mechanism, in response to the input control signal; and an abnormality detection module that determines whether the adjustable valve mechanism is abnormal or normal, based on the theoretical value and the observed value.