Motor-vehicle central lock system with transponder in key

US5561420A · kind A · utility

Assignee

• Kiekert AG · DE

Inventors

• Frank Kleefeldt · Heiligenhaus, DE
• Peter Bartel · Hattingen, DE
• Willfried Ostermann · Essen, DE
• Fred Welskopf · Herne, DE

Key dates

• Filing date: Jun 1, 1995
• Grant date: Oct 1, 1996
• Expiry date: Jun 1, 2015

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T70/5973
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A motor-vehicle lock system has a remote operator separate from the motor vehicle and having a key part having a predetermined bitting, a transmitter actuatable to transmit a main signal containing a main code word, and a transponder independent of the transmitter for receiving an interrogation signal and thereupon generating a callback signal containing a callback code word. A lock provided with a switch is actuatable mechanically by the key part to operate the switch. A receiver in the motor vehicle connected to a central lock controller receives the main signal including the main code word, extracts the main code word from the transmitted main signal, compares the extracted main code word with a predetermined main code word, and sends a release signal to the controller when the extracted main code word corresponds to the predetermined main code word to actuate the elements. A transceiver in the motor vehicle at the one lock is connected to the controller for, when the switch is actuated, generating the interrogation signal, receiving the callback signal containing the callback code word, extracting the callback code word from the callback signal, comparing the extracted callback…