Christine J Traylor

US Patent:

48477680, Jul 11, 1989

Filed:

Aug 29, 1988

Appl. No.:

7/237762

Inventors:

Ellen S. Schwartz - Warren MI
Donald J. Smolenski - St. Clair Shores MI
John D. Keersmaekers - Mason MI
Christine M. Traylor - Flint MI
Gary J. Wallo - Union Lake MI

Assignee:

General Motors Corporation - Detroit MI

International Classification:

G06F 1520
F01M 1110

US Classification:

36442403

Abstract:

An apparatus and method is disclosed for indicating useful life of motor vehicle angine oil during engine operation based on engine oil temperature without direct measurement thereof. Following the initiation of engine operation, engine oil temperature is calculated from a warmup equation until calculated engine oil temperature exceeds a warmup reference, whereupon it is calculated from an equilibrium equation, both of which equations being linear combinations of engine operating parameters other than engine oil temperature itself. The warmup equation includes a constant term, a reference temperature term fixed at the begining of engine operation and a term increasing proportionally with the number of engine cylinder firings. The equilibrium equation includes a constant term, an engine temperature term and a term proportional to engine speed and may also include a term proportional to an engine cooling factor.