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. 26, 2014
Filed:
Mar. 16, 2010
Hirokazu Shimizu, Isesaki, JP;
Hirokazu Shimizu, Isesaki, JP;
Hitachi Automotive Systems, Ltd., Hitachinaka-shi, JP;
Abstract
A rotation detecting device and a rotation detecting method determines normal rotation/reverse rotation of a rotating shaft based on a rotation signal different between the normal rotation and the reverse rotation of the rotating shaft. The rotation signal is set to have a pulse width different between the normal rotation and the reverse rotation of a crankshaft that is an output shaft of an internal combustion engine. By determining whether or not the pulse width is greater than a threshold value, the normal rotation or the reverse rotation of the crankshaft is detected. Whether or not the crankshaft is rotating normally is determined based on engine rotating speed, a cylinder in which a piston is in a predetermined position, an engine load, a starter switch, intake pressure, battery voltage, and the like. When the condition for the normal rotation is satisfied, the threshold of the pulse width is set based on a pulse width of a rotation signal measured at this time.