Electric Steering Apparatus for Floor Transport Vehicle

• US 20070295542A1
• Filed: 06/22/2007
• Published: 12/27/2007
• Est. Priority Date: 06/23/2006
• Status: Abandoned Application

• Current Assignee: Kordel Antriebstechnik GmbH (Kordel Holding GmbH)
• Original Assignee: Kordel Antriebstechnik GmbH (Kordel Holding GmbH)
• Inventors: Raue, Josef
• Application Number:
  US11/767,462
• Publication Number:
  US 20070295542A1
• Time in Patent Office: Days
• US Class Current: 180/6.38
• CPC Class Codes: B62D 5/0418 Electric motor acting on road wheel carriers
• CPC Class Codes: B62D 7/023 Steering turntables
• CPC Class Codes: B66F 9/07572 Propulsion arrangements

Abstract

An electric steering apparatus, particularly suited for floor transport vehicles, comprises a housing, a steering motor operably connected to a reduction gear stage wherein the reduction gear stage is operably connected to rotating bearing assembly coupled in a torque-proof manner to a steerable running wheel. Precise steering motion with continuous control capability is provided by translating the drive motor output through the reduction gear stage to the rotating bearing assembly. Finer and more precise steering motion than that afforded by conventional hydraulically actuated steering units is thus provided. Steering motion is also advantageously continuously controllable through rotation angle sensors integral to the rotating bearing assembly. A three stage planetary reduction gear systems coupled to a rotating bearing assembly advantageously transfers large torques, so that large loads may be accommodated while maintaining fine steering control.

Claims

1. A steering apparatus for a vehicle comprising:

a steering motor comprising a rotating drive shaft;

a reduction gear stage;

a rotating bearing assembly, and;

a rotatable running wheel carrier,

said rotating drive shaft in operable connection with said reduction gear stage and said reduction gear stage in operable connection with said rotating bearing assembly, said reduction gear stage further comprising;

a housing, and;

means for transmitting the rotational force of said drive shaft to said rotating bearing assembly and for reducing the rotational speed of the rotational force transmitted;

said rotating bearing assembly comprising an inner race and an outer race, said inner race in torque-proof connection with said rotatable running wheel carrier, said outer race in torque-proof connection with said housing, wherein the rotational force of said drive shaft is transmitted through said reduction gear stage to said rotating bearing assembly so that said inner race and said rotatable running wheel carrier rotate in relation to said outer race and at a rotational speed slower than the rotational speed of said rotating drive shaft.

2. The steering apparatus of claim 1 wherein said steering motor, said reduction gear stage, and said rotating bearing assembly are arranged symmetrically around the axis central to said drive shaft.

3. The steering apparatus of claim 1 wherein said means for transmitting the rotational force of said drive shaft to said rotating bearing assembly and for reducing the rotational speed of the rotational force transmitted comprises at least one planetary gear.

4. The steering apparatus of claim 3 wherein said inner race comprises a planet carrier for at least one planetary gear.

5. The steering apparatus of claim 1 wherein said means for transmitting the rotational force of said drive shaft to said rotating bearing assembly and for reducing the rotational speed of the rotational force transmitted comprises a plurality of planetary gears arranged in a plurality of stages.

6. The steering apparatus of claim 5 wherein said inner race comprises a planet carrier for at least one planetary gear.

7. The steering apparatus of claim 1 wherein said rotatable wheel carrier is integral to said inner race.

8. The steering apparatus of claim 1 wherein a seal is disposed between said inner race and said outer race.

9. The steering apparatus of claim 1 wherein said steering motor comprises an electric motor.

10. The steering apparatus of claim 1 further comprising a gear disc and a rotation angle sensor, said gear disc operably connected to said inner race wherein said gear disc rotates in relation to rotation of said inner race, said gear disc further operably connected to said rotation angle sensor wherein rotation of said gear disc is detectable by said rotation angle sensor.

11. The steering apparatus of claim 4 or claim 6 further comprising a gear disc and a rotation angle sensor, said gear disc disposed on the axis of at least one planetary gear and operably connected to said inner race wherein said gear disc rotates in relation to rotation of said inner race, said gear disc further operably connected to said rotation angle sensor wherein rotation of said gear disc is detectable by said rotation angle sensor.

12. A steering apparatus for a vehicle comprising

a steering motor, said steering motor comprising a rotating drive shaft;

a rotatable wheel carrier, and;

means for transmitting the rotational force from said drive shaft to rotate said rotatable wheel carrier at a rotational speed slower than the speed of said rotating drive shaft.

13. The steering apparatus of claim 12 wherein said steering motor comprises an electric motor.

14. The steering apparatus of claim 12 further comprising means for detecting the relative rotation of said rotatable wheel carrier.

15. The steering apparatus of claim 14 wherein said means for detecting the relative rotation of said rotatable wheel carrier comprises a rotation angle sensor operably connected to said rotatable wheel carrier.

16. The steering apparatus of claim 12 where said means for transmitting the rotational force from said drive shaft to rotate said rotatable wheel carrier at a rotational speed slower than the speed of said rotating drive shaft comprises at least one planetary gear and at least one planet carrier.

17. The steering apparatus of claim 16 wherein said means for detecting the relative rotation of said rotatable wheel carrier comprises a rotation angle sensor operably connected to at least one planetary gear.

18. The steering apparatus of claim 12 where said means for transmitting the rotational force from said drive shaft to rotate said rotatable wheel carrier at a rotational speed slower than the speed of said rotating drive shaft comprises a plurality of planetary gears and a plurality of planet carriers.

19. The steering apparatus of claim 18 wherein said means for detecting the relative rotation of said rotatable wheel carrier comprises a rotation angle sensor disposed on the axis of at least one planetary gear.

20. The steering apparatus of claim 18 wherein said plurality of planetary gears and plurality of planet carriers are disposed in a plurality of stages.

21. The steering apparatus of claim 21 wherein said means for detecting the relative rotation of said rotatable wheel carrier comprises a rotation angle sensor disposed on the axis of at least one planetary gear.