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:
Nov. 02, 2004
Filed:
Mar. 03, 2003
Masahiko Nomura, Tokyo, JP;
Kohji Hashimoto, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A temperature control apparatus for an exhaust gas sensor can promptly heat the exhaust gas sensor with an electric heater up to an activation temperature while preventing thermal shock damage thereof due to water immediately after engine starting. Energization of an electric heater arranged near an exhaust gas sensor is controlled by a CPU cooperating with a ROM through a switching element. A low voltage is supplied for evaporation of the water by a first preheater immediately after engine starting, and enhanced preheating is subsequently carried out by a second preheater for preventing thermal shock on the exhaust gas sensor. Thereafter, a heating controller performs automatic control with a proper activation temperature of the exhaust gas sensor being made as a target. The temperature controlled by the first preheater is set to such a temperature level at which rapid cooling damage of the exhaust gas sensor due to the water will not be caused but the water can be evaporated.