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:
Sep. 04, 2012
Filed:
Nov. 13, 2009
Hiromichi Yasuda, Gotemba, JP;
Hiromichi Yasuda, Gotemba, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, JP;
Abstract
An object of the present invention is to provide an abnormality detection device for an in-cylinder pressure sensor and an abnormality detection method for an in-cylinder pressure sensor that is able to detect preload loss abnormality of an in-cylinder pressure sensor. An in-cylinder pressure sensor has a strain gauge element to which preload was given. Under an operating state of an internal-combustion engine, it is judged whether Pim/Pex that is a ratio of intake pressure Pim to exhaust gas pressure Pex is 1. Reset of temperature drift is performed when Pim/Pex is 1. If an output voltage which serves as a base of calculation of Pim after the reset of a temperature drift is equal to a circuit limit value, existence of preload loss abnormality is determined.