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. 02, 1988
Filed:
Sep. 09, 1986
Andreas van den Boom, Gelsenkirchen, DE;
Karl-Heinz Stellberger, Velbert, DE;
Hulsbeck & Furst GmbH & Co. KG., Velbert, DE;
Abstract
A simple and economical, yet tamper-proof, electronic locking apparatus for motor vehicles features an electronic key and an electronic lock, which each contain a synchronized, constantly operating, precision oscillator. The output of each oscillator is applied at a predetermined counting rate to a respective number sequence generator. Both generators contain the same predetermined number sequence, which they step through at the same clock rate, applying the instantaneous value of the count to a first input of a respective computer. A second input of each computer is connected to a fixed memory which supplies a permanent, characteristic code number to the computer. Both the count state and the characteristic code number are combined using corresponding algorithms in the key and in the lock to produce a combination code. The key-produced combination code is sent from a transmitter in the key to a receiver in the lock and compared there with the lock-produced combination code. In the event of a successful comparison, a control pulse is generated, which actuates various positioning means in the lock.