Automatic steering device for an electrically controllable hydraulic steering system, especially for an agricultural vehicle

US5828971A · kind A · utility

Assignee

• Claas KGaA · DE

Inventors

• Norbert Diekhans · Gütersloh, DE
• Ludger Autermann · Drensteinfurt, DE
• Stefan Hagedorn · Warendorf, DE
• Jochen Huster · Vellmar, DE

Key dates

• Filing date: Mar 8, 1996
• Grant date: Oct 27, 1998
• Expiry date: Mar 8, 2016

Classification

• Technology area (CPC G): Physics
• CPC primary: G05D1/0255
• WIPO field: Control
• WIPO sector: Instruments

Abstract

The automatic steering device for an electrically controllable hydraulic steering system automatically controls steered wheels (HR) of a steered vehicle, especially an agricultural machine, according to at least one electronic steering control signal (SHL,SHR). The automatic steering device includes one or more locating devices (OV) producing one or more locating signals (OS), a regulating device (ST) which periodically digitizes the locating signal or signals (OS), and produces the at least one electronic steering control signal by a logic combination of the digitized locating signal or signals and a predetermined locating criterion, particularly a lateral displacement of the vehicle from an edge of an agricultural material, to minimize a deviation of the locating signal or signals determined according to the predetermined criterion so that the at least one electronic steering control signal (SHL,SHR) increases in an approximately proportional manner in the vicinity of a null deviation from the predetermined locating criterion but increases progressively beyond the vicinity of the null deviation. A fuzzification of the control criteria and a defuzzification of at least one interme…