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:
May. 10, 1994
Filed:
Jul. 17, 1992
Kabushiki Kaisha Tokai Rika Denki Seisakusho, Aichi, JP;
Abstract
An object of this invention is to provide a door unlocking device adapted unlock a door by transmitting a signal in the air through a signal transmitter, which can unlock the door even when the power source of the signal transmitter, namely, the battery has consumed up. With a door unlocking device, upon insertion of an ignition key into the rotor of a key cylinder, a shutter is opened to operate a shutter switch. Under this condition, the rotor is turned in opposite directions from the neutral position according to a predetermined rotor turning pattern. The rotor turning pattern is discriminated by a rotor-turning-pattern discriminating circuit. Ensuring that the rotor turning pattern is the one predetermined for unlocking the door, the rotor-turning-pattern discriminating circuit activates an electric operating mechanism to cause a lock mechanism to unlock the door.