Slip-controlled brake system for all-wheel driven automotive vehicle

US4746173A · kind A · utility

Assignee

• Alfred Teves GmbH · DE

Inventors

• Helmut Fennel · Bad Soden, DE
• Hans Wupper · Friedrichsdorf, DE
• Gunther Buschmann · Griesheim, DE
• Norber Ehmer · Bad Soden, DE

Key dates

• Filing date: Oct 2, 1986
• Grant date: May 24, 1988
• Expiry date: Oct 2, 2006

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S303/06
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A slip-controlled hydraulic brake system for all-wheel driven motor vehicles equipped with lockable differentials (2, 3) is provided with sensors (S.sub.1 -S.sub.4, 33-36) for measuring the rotational behavior of the wheels. Electronic circuits (44) are provided for logic combining and processing the sensor signals, and for generating braking pressure control signals by way of which the brake pressure in the individual wheel brakes (16-19) is variable in response to the rotational behavior of the wheels and to a reference variable. To compensate the increased moments of inertia as a result of the moments transmission, by way of the lockable differentials (2, 3) in this brake system the brake pressure in the rear-wheel brakes (18, 19), can be modulated at a lower control frequency as compared with the brake pressure in the front-wheel brakes (16, 17). The reduction in the control frequency of the rear-wheel brake pressure is determined by driving-dynamic criteria, for example, by the average motor vehicle deceleration or by the motor vehicle speed.