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:
Feb. 20, 1979
Filed:
Aug. 22, 1977
Robert Bosch GmbH, Stuttgart, DE;
Abstract
An apparatus for use in association with a fuel mixture preparation system for an internal combustion engine in which the output signal from an oxygen sensor located in the exhaust system is used to provide closed-loop control of the mixture ratio supplied by the mixture preparation system. The apparatus includes a principal comparator in which the sensor signal is compared with a reference value and a subsequent integrator which supplies correcting signals to the mixture controller. A special circuit between the principal comparator and the integrator can delay the signal transmission between these two elements in one direction of change, thereby causing an effective shift of the point of operation of the control loop to a different point in the sensor output curve, to compensate for aging, etc. The feedback branch of the integrator includes circuitry which effectively provides two different constants of integration to enhance smooth running at low engine speeds and to improve the control response at high engine speeds. The invention may be used with any kind of mixture preparation system, e.g., carburetors, intermittent injection systems and continuously acting injection systems.