Steering system for a vehicle

• US 6,394,218 B1
• Filed: 08/18/2000
• Issued: 05/28/2002
• Est. Priority Date: 09/03/1999
• Status: Expired due to Fees

• Current Assignee: TRW Fahrwerksysteme GmbH & Co. KG (Presswerk Krefeld GmbH & Co. KG)
• Original Assignee: TRW Fahrwerksysteme GmbH & Co. KG (Presswerk Krefeld GmbH & Co. KG)
• Inventors: Heitzer, Heinz-Dieter
• Primary Examiner(s): DePumpo, Daniel G.
• Application Number:
  US09/641,582
• Time in Patent Office: 648 Days
• Field of Search: 180/402,443,444,446
• US Class Current: 180/402
• CPC Class Codes: B62D 15/0245 Means or methods for determination of the central position of the steering system, e.g. straight ahead position
• CPC Class Codes: B62D 5/003 Backup systems, e.g. for manual steering B62D5/30 takes precedence
• CPC Class Codes: B62D 5/0427 the axes being coaxial
• CPC Class Codes: B62D 5/0448 Ball nuts

Abstract

A steering system comprises a steering linkage and two positioners capable of positioning the steering linkage in unison. Each positioner comprises an electronic control circuit, a servomotor and a position sensor for sensing a position of the servomotor.

Claims

1. A steering system for a vehicle, said steering system comprising:

a housing;

a steering linkage and two positioners located in said housing, each of said two positioners positioning the steering linkage, each positioner comprising an electronic control circuit, a servomotor, and a position sensor for sensing a position of said servomotor,

said steering linkage comprising a translatory displaceable steering spindle, and a recirculating ball nut which is driven by each of said two servomotors,

each of said two servomotors comprising a rotor, each of said rotors having an axis of rotation coinciding with a longitudinal axis of said steering spindle,

each of said rotors being encapsulated separate from each other in a chamber defined by wall portions of said housing.

2. The steering system as set forth in claim 1, wherein said two rotors of said servomotors are arranged on a common drive spindle.

3. The steering system as set forth in claim 1, wherein said two electronic control circuits are encapsulated separate from each other.

4. The steering system as set forth in claim 1, wherein each of said two servomotors is dimensioned such that a torque generated by said two servomotors at a maximum is not sufficient to move said steering linkage when said vehicle is in a standstill position.

5. The steering system as set forth in claim 1, wherein a switch is provided for sensing a specific position of said steering linkage.

6. The steering system as set forth in claim 1, wherein a position sensor is provided for sensing a position of said steering linkage.

7. The steering system as set forth in claim 1, wherein a force sensor is arranged at said steering linkage.

8. The steering system as set forth in claim 1, wherein a sensor is provided for sensing a current furnished to said servomotors.

9. The steering system as set forth in claim 1, wherein a sensor is provided for sensing at least one of a vehicle speed, a steering angle and a yaw rate of said vehicle.