Hydraulic steering

• US 7,770,687 B2
• Filed: 04/26/2007
• Issued: 08/10/2010
• Est. Priority Date: 04/28/2006
• Status: Active Grant

• Current Assignee: Danfoss Power Solutions ApS (Danfoss A/S)
• Original Assignee: Sauer-Danfoss Aps (Bitten Og Mads Clausens Fond)
• Inventors: Entwistle, Richard Thomas, Dixen, Carl Christian, Crow, Steve
• Primary Examiner(s): Morris; Lesley
• Assistant Examiner(s): Stabley; Michael R
• Application Number:
  US11/740,371
• Publication Number:
  US 20070251755A1
• Time in Patent Office: 1,202 Days
• Field of Search: 180/403, 180/405, 180/406, 180/417, 180/421
• US Class Current: 180/417
• CPC Class Codes: B62D 5/003 Backup systems, e.g. for manual steering B62D5/30 takes precedence
• CPC Class Codes: B62D 5/091 Hydraulic steer-by-wire systems, e.g. the valve being actuated by an electric motor

Abstract

The invention concerns a hydraulic steering with a steering motor arrangement having at least one steering motor, and with at least two steering circuits, each having a steering valve that interrupts a path from a pressure supply to the steering motor arrangement in the neutral position and releases a path from the pressure supply to the steering motor arrangement on a movement out of the neutral position. It is endeavored to simplify the embodiment of such a steering. For this purpose, the steering valve (5a, 5b) has two end positions, one on each side of the neutral position, in which positions a path from the pressure supply (15, 21) to the steering motor arrangement (2) is interrupted.

Claims

1. A hydraulic steering with a steering motor arrangement having at least one steering motor, and with at least two steering circuits, each having a steering valve that interrupts a path from a pressure supply to the steering motor arrangement in the neutral position and releases, in dependence of the direction, a path from the pressure supply to the steering motor arrangement on a movement out of the neutral position, characterised in that the steering valve has two end positions, one on each side of the neutral position, in which positions a path from the pressure supply to the steering motor arrangement is interrupted.

2. The steering according to claim 1, wherein the steering valves are made as pilot-controlled steering valves.

3. The steering according to claim 2, wherein a pilot control valve is allocated to each steering valve.

4. The steering according to claim 3, wherein each pilot control valve has its own actuator.

5. The steering according to claim 1, wherein each steering valve has a position sensor.

6. The steering according to claim 1, wherein the steering valve has a spring arrangement taking it to the neutral position.

7. The steering according to claim 1, wherein the steering valve is a 5-position valve.

8. The steering according to claim 1, wherein a control device is provided, which controls at least two steering valves at the same time.

9. The steering according to claim 1, wherein the pressure supply has several pumps.

10. The steering according to claim 9, wherein the pumps are connected to inlets of an automatic selection device whose outlet is connected to the steering circuits.

11. The steering according to claim 9, wherein one of the pumps is driven by a combustion engine and the other pump is driven by an electric motor or a wheel, the pump driven by the combustion engine being a displacement pump.

12. The steering according to claim 11, wherein the displacement pump has a load-sensing inlet, which is connected to an electrically activated load-sensing control valve.

13. The steering according to claim 1, wherein the steering motor arrangement has a steering motor that is connected to at least two steering circuits.