System for controlling the speed of an automotive vehicle

US4273208A · kind A · utility

Assignee

• Wabco Fahrzeughremsen GmbH · DE

Inventor

• Peter Liermann · Barsinghausen, DE

Key dates

• Filing date: Apr 30, 1979
• Grant date: Jun 16, 1981
• Expiry date: Apr 30, 1999

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B60W2552/15
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

Signals representing actual and desired speeds of a vehicle are separately applied to a plurality of parallel comparator channels or devices. Each comparator device responds to a different level of difference between the speed signals, when actual is greater than desired, to produce output signals at successively higher levels. The first comparator device controls a first deceleration device, e.g., an exhaust throttle, to reduce vehicle speed when an output signal is produced at the first preselected level of difference. The second and third comparator devices control the second and third deceleration devices, respectively, e.g., an eddy-current brake, automatic transmission, etc., when each produces an output signal at its preselected difference level, but only if the next lower comparator output has enabled a gate or switch coupling the higher level comparator and deceleration devices. Thus the deceleration control is increased in successive steps as the speed difference increases if each successive deceleration device is actuated in order by the associated comparator.