The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 01, 1977
Filed:
Jan. 19, 1976
Lewis R Hetzler, Anderson, IN (US);
Gerald O Huntzinger, Anderson, IN (US);
William P Winstead, III, Anderson, IN (US);
Thomas A Zickel, Anderson, IN (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A read only memory is pre-programmed to produce an output binary signal representation of a predetermined ignition spark timing angle based upon the instantaneous value of both of two selected engine operating parameters at each of a plurality of respective selected points within the range of values in response to respective input address signals. Over the range of values of the two selected engine operating parameters, therefore, the read only memory generates a three-dimensional surface of ignition spark timing angles. The binary signal representations of the ignition spark timing angles retrieved from the read only memory are varied in accordance with engine manifold vacuum and actual atmospheric pressure to tilt the three-dimensional surface generated by the read only memory about a selected engine parameter value as an axis in an amount substantially inversely proportional to actual atmospheric pressure.