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:
Feb. 26, 2008
Filed:
Mar. 10, 2006
Yasuaki Kishimoto, Tokyo, JP;
Toshiaki Hata, Tokyo, JP;
Yasuaki Kishimoto, Tokyo, JP;
Toshiaki Hata, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A vehicular electronic key system includes an on-board device that mutually communicates with a portable device, and operates control equipment installed on a vehicle when specific information from the portable device is authenticated. The on-board device includes a distance storage section for storing travel distances of the vehicle, and a warning section for warning that the portable device disappeared when communication was stopped between the on-board device and the portable device. The on-board device communicates with the portable device each time a predetermined distance is travelled, stores the travel distance at each communication time point into the distance storage section, and drives, upon detection that a signal transmitted from the portable device was disrupted, the warning section to warn an undetected region between the last travel distance stored immediately before the transmitted signal was disrupted and a travel distance at a time point at which the transmitted signal was disrupted.