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:
Jun. 30, 1998
Filed:
Aug. 29, 1994
Yoshiyuki Mizuno, Aichi, JP;
Sadao Kokubu, Aichi, JP;
Hisashi Aoki, Aichi, JP;
Takashi Mizuno, Aichi, JP;
Kabushiki Kaisha Tokai Rika Denki Seisakusho, Aichi, JP;
Abstract
When an ignition switch detects that a key rotor of an ignition key cylinder has been turned to the accessory position by a key, a controller energizes a primary coil to cause it to output a high-frequency signal. In the key, a secondary battery is charged with a constant DC voltage generated from an AC voltage induced across a secondary coil. A transmission circuit is powered by the secondary battery, and allowed by a timer circuit to transmit a radio signal including an identification code during a predetermined period after the high-frequency signal is received by the key. Alternatively, the controller energizes the primary coil plural times with a cycle consisting of predetermined output and pause periods if the transmitted identification code does not coincide with a preset identification code at the first comparing attempt.