Method and apparatus for detecting a defective pressure switch

US6474149B1 · kind B1 · utility

Assignee

• Continental Teves AG & Co. OHG · DE

Inventors

• Norbert Ehmer · Bad Orb, DE
• Thomas Proger · Rödermark, DE
• Markus Zenzen · Hattersheim, DE

Key dates

• Filing date: Mar 1, 1999
• Grant date: Nov 5, 2002
• Expiry date: Mar 1, 2019

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B60T2270/415
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

The invention provides a method of detecting a defective condition on a pressure switch arrangement which at least assumes a defective condition on the said pressure switch assembly whenever a signal arrives at an input of an electronic computing unit which cannot be associated either to the opened or to the closed condition of the pressure switch. Moreover, a defective condition on the pressure switch arrangement mounted in the brake system of a vehicle is assumed, once the pressure switch signal refers to an actuated brake although the vehicle is significantly accelerated. Conversely, a defective condition is also assumed if the vehicle significantly decelerates although the pressure switch signal refers to a lack of brake pressure. Also, an appropriate pressure switch arrangement is provided which, with the pressure switch closed, generates a rectangular signal and, with the pressure switch opened, generates a high level on the input II of an electronic computing unit. With an incoming low level, an error on the pressure switch arrangement is assumed.