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:
Aug. 23, 1994
Filed:
Jun. 09, 1993
Hiroyoshi Suzuki, Himeji, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
An air-fuel ratio sensor comprises an oxygen concentration cell device, an oxygen pump device, a heater for heating the oxygen concentration cell device and the oxygen pump device, a pump current cut means for stopping the supply of the pump current, first and second timers for controlling the condition of stopping the pump current, and a controller for starting the heating of the heater under the condition of stopping the pump current, to the pump device and for removing the stopping of the pump current for a predetermined time at predetermined intervals from the starting of supplying power to the heater, by means of the first timer, wherein when the pump current shows a predetermined value or higher, the pump current is stopped and the second timer is started, and when the operation of the second timer is finished, the judgment of the activation of the sensor is made, and at the same time, the stopping of the pump current is removed.