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. 01, 2005
Filed:
Jun. 27, 2002
Hideki Masudaya, Miyagi-ken, JP;
Hideki Masudaya, Miyagi-ken, JP;
Alps Electric Co., Ltd., Tokyo, JP;
Abstract
In a passive entry comprising a car-mounted transmitter-receiver and one or more portable transmitter-receivers, the car-mounted transmitter-receiver generates a request signal, when any of the portable transmitter-receivers receives the request signal, an answer signal is transmitted in response to the request signal, and when the car-mounted transmitter-receiver receives the answer signal, the car door is locked or unlocked. The car-mounted transmitter-receiver has a timer for counting time from transmission of the request signal to reception of the answer signal, and when the answer signal is received, recognizes the answer signal as legal only when an elapsed-time value counted by the timer is within a valid elapsed-time value set in advance, and exercises control of a controlled apparatus, such as, e.g., locking and unlocking of the car door.