Hydraulic steering

• US 20050205337A1
• Filed: 02/18/2005
• Published: 09/22/2005
• Est. Priority Date: 02/27/2004
• Status: Active Grant

• Current Assignee: Danfoss Power Solutions ApS (Danfoss A/S)
• Original Assignee: Sauer-Danfoss Aps (Bitten Og Mads Clausens Fond)
• Inventors: Jensen, Kjeld Buus, Nielsen, Finn Visgaard, Thomsen, Svend Erik, Porskrog, Bendt
• Granted Patent: US 7,610,988 B2
• Time in Patent Office: Days
• US Class Current: 180/417
• CPC Class Codes: B62D 1/286 Systems for interrupting non-mechanical steering due to driver intervention
• CPC Class Codes: B62D 5/093 Telemotor driven by steering wheel movement hydraulic steering gear B62D3/14

Abstract

The invention concerns a hydraulic steering with a steering initiator, a steering unit with feedback properties, which can be activated by the steering initiator, the steering unit having a supply connection arrangement with a pressure connection (P) and a tank connection (T) and a working connection arrangement with two working connections (L, R), an auxiliary-force operated steering valve, which is located in parallel with the steering unit between the supply connection arrangement (P, T) and the working connection arrangement (L, R), and a feedback suppressing device, which is active, when the steering valve is active. It is endeavoured to find a simple manner of ensuring the priority of the steering initiator over the steering valve. For this purpose, the steering initiator interacts with an activation sensor, which deactivates the feedback suppressing device on an activation of the steering initiator.

Claims

1. A hydraulic steering with a steering initiator, a steering unit with feedback properties, which can be activated by the steering initiator, the steering unit having a supply connection arrangement with a pressure connection and a tank connection and a working connection arrangement with two working connections, an auxiliary-force operated steering valve, which is located in parallel with the steering unit between the supply connection arrangement and the working connection arrangement, and a feedback suppressing device, which is active, when the steering valve is active, wherein the steering initiator interacts with an activation sensor, which deactivates the feedback suppressing device on an activation of the steering initiator.

2. The steering in accordance with claim 1, wherein the steering initiator exists in the form of a steering handwheel, which is connected with the steering unit via a steering shaft, the activation sensor determining an activation of the steering handwheel.

3. The steering in accordance with claim 2, wherein the activation sensor interacts with the steering shaft.

4. The steering in accordance with claim 2, wherein the activation sensor is a torque sensor.

5. The steering in accordance with claim 2, wherein the activation sensor is a rotation angle sensor.

6. The steering in accordance with claim 1, wherein the feedback suppressing device has a brake, which acts upon the steering initiator.

7. The steering in accordance with claim 6, wherein the brake acts upon the steering handwheel via the steering shaft.

8. The steering in accordance with claim 7, wherein the activation sensor is located between the brake and the steering handwheel.

9. The steering in accordance with claim 6, wherein the brake is an electrically activated brake.

10. The steering in accordance with claim 6, wherein the brake generates a maximum braking torque of 8 Nm.

11. The steering in accordance with claim 1, wherein the feedback suppressing device has a change-over valve acting upon the working connection arrangement.

12. The steering in accordance with claim 11, wherein in its activated position the change-over valve blocks at least one working connection (L, R).

13. The steering in accordance with claim 11 connects the steering valve with a steering motor, and in its deactivated position connects the steering unit with the steering motor.