초록 ▼

An electronic engine controller infers the instantaneous temperature of lubricating oil in an engine by determining a steady state oil temperature value as a function of engine speed and aircharge, determining an oil temperature time constant as a function of mass air flow rate and determining the i

An electronic engine controller infers the instantaneous temperature of lubricating oil in an engine by determining a steady state oil temperature value as a function of engine speed and aircharge, determining an oil temperature time constant as a function of mass air flow rate and determining the instantaneous oil temperature as a function of the steady state oil temperature and the oil temperature time constant. The engine controller also determines an oil change interval as a function of the inferred oil temperature and the number of engine revolutions.

대표청구항 ▼

In a vehicle which includes lubricating oil for lubricating engine components, an oil change indicator which provides an operator of the vehicle of the expiration of an oil change interval, and a means for generating an oil change reset signal which causes initiation of said oil change interval, a s

In a vehicle which includes lubricating oil for lubricating engine components, an oil change indicator which provides an operator of the vehicle of the expiration of an oil change interval, and a means for generating an oil change reset signal which causes initiation of said oil change interval, a system for informing an operator of the vehicle of the expiration of said oil change interval, comprising, in combination: means for initializing an oil quality value, which is indicative of the efficacy of said oil; means for inferring the temperature of said oil as a function of a first value indicative of the rotational speed of the engine, a second value indicative of aircharge entering an intake manifold of the engine, and a third value indicative of engine coolant temperature; and means for periodically altering, upon the passage of a variable number of engine revolutions, said oil quality value, comprising, means, responsive to said oil temperature for generating an oil stress value which is indicative of a rate at which the oil degrades; means for altering said oil quality value as a function of said oil stress value and a value indicative of said variable number of engine revolutions; means for comparing said altered oil quality value to a predetermined quality value, which is indicative of a predetermined maximum oil life; and means for providing a first indication to said vehicle operator if said altered oil quality value indicates an effective oil life which is greater than an oil life indicated by said predetermined quality value.