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. 01, 1998
Filed:
Oct. 28, 1996
Hiroaki Kawai, Anjo, JP;
Katsu Hattori, Nagoya, JP;
Aisin Seiki Kabushiki Kaisha, Kariya, JP;
Abstract
The invention is directed to a method and apparatus for detecting a tire inflation pressure of a vehicle tire. The apparatus includes a device for producing an oscillating electric signal having a vibration frequency component of the vehicle tire. A wavelet transformer transforms the oscillating electric signal by a wavelet function into a wavelet coefficient. The wavelet function is provided on the basis of a mother wavelet function localized in time, scaled in response to a scale parameter, and shifted in response to a shift parameter indicative of a time localization. Then, an extracting device extracts a resonance frequency from the vibration frequency component of the vehicle tire on the basis of the wavelet coefficient, and an estimating device estimates the tire inflation pressure on the basis of the resonance frequency. The apparatus may further include a warning device for warning a decrease of the tire inflation pressure when the resonance frequency decreases to an extent that a difference between the resonance frequency and the reference frequency exceeds a predetermined frequency.