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:
Apr. 12, 2005
Filed:
Oct. 09, 2003
Hideki Masudaya, Miyagi-ken, JP;
Hideki Masudaya, Miyagi-ken, JP;
Alps Electric Co., Ltd., Tokyo, JP;
Abstract
A tire air pressure monitor includes tire air pressure sensors and transmitters proximate to tires; receiving antennas which receive transmitting signals from the transmitters; phase shifters which shift signal phases received from the antennas by control voltages; a synthesizer which synthesizes outputs from the phase shifters; and a meter which detects an output level from the synthesizer. The phase differences between the antennas are different and the control voltages for the phase shifters are obtained in advance, which maximizes the output level from the synthesizer dependent on the tire mounting positions. An association table relates the tire mounting positions to the control voltages and the control voltages are controlled so that the output level from the synthesizer is maximized with respect to a transmitting signal from any one of the tire mounting positions. The tire mounting positions is identified by comparing values of the control voltages thus controlled.