Method of operating a device for monitoring vehicle-tire pressures and indicating changes in pressure by radio

US6112165A · kind A · utility

Assignee

• Doduco GmbH · DE

Inventors

• Gunter Uhl · Waibstadt, DE
• Norbert Normann · Mühlacker, DE
• Gunter Schulze · Holle, DE
• Ralf Kessler · Heidelberg, DE

Key dates

• Filing date: May 11, 1998
• Grant date: Aug 29, 2000
• Expiry date: May 11, 2018

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B60C23/0408
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A method of operating a device for monitoring vehicle-tire pressures and indicating changes in pressure by radio, which is arranged in the valve of the pneumatic tire and contains a power source; a pressure sensor; an analog/digital converter for digitizing the pressure signal obtained from the pressure sensor; a memory for storing the pressure signal; a transmitter; a comparator, in particular in a module with a microprocessor, which compares the pressure signal with a previously stored comparison pressure signal, generates a signal if the deviation of the pressure signal from the comparison pressure signal exceeds a threshold, and activates the transmitter, which thereupon transmits a datum regarding the detected deviation to a receiver arranged in the vehicle; and a timing switch which activates the device at time intervals for a measurement and comparison operation and otherwise keeps it deactivated for purpose of power conservation. The comparator stores the pressure signal and, with said pressure signal, constitutes a new comparison pressure signal which replaces the previous comparison pressure signal.