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:
Dec. 11, 1979
Filed:
Aug. 12, 1977
Abstract
An exhaust gas recirculation (EGR) control system for an internal combustion engine, in which an EGR control valve including a vacuum-operated actuator governs the flow of recirculated exhaust gas according to the admission of air into the engine. To accomplish the control with high precision, the control system includes a flow sensor which provides an electrical signal representing the volume flow rate of air in the induction passage and a control circuit for controlling the magnitude of vacuum for the EGR valve through the operation of an electromagnetic valve based on the signal from the flow sensor. Optionally the control system has another flow sensor which provides an electrical signal representing the volume flow rate of recirculated exhaust gas to the control circuit to accomplish a feedback control.