Steering stop

Patent metadata

Field	Value
Publication number	US-9475519-B2
Application number	US-201414913583-A
Country	US
Kind code	B2
Filing date	Aug 13, 2014
Priority date	Aug 23, 2013
Publication date	Oct 25, 2016
Grant date	Oct 25, 2016

Abstract

A steering stop for a steer-by-wire steering system, includes a steering shaft for functionally connecting to a steering wheel, wherein a pressure chamber is provided for each direction of rotation of the steering shaft. A rotation of the steering shaft produces a reduction in the volume of a corresponding pressure chamber, and the steering stop also comprises a hydraulic valve such that resistance against a further rotation of the steering shaft is generated by the operation of said hydraulic valve when predetermined environmental conditions are met.

First claim

The invention claimed is:

1. A steering stop excluding a mechanical or hydraulic coupling to mechanical components for turning a steer-by-wire steering system, said steering stop comprising:
a steering shaft for connection with a steering handle;
pressure chambers for a hydraulic fluid, one of said pressure chambers provided for each direction of rotation of the steering shaft, wherein a rotation of the steering shaft in one direction of rotation causes a reduction of the volume of one of the pressure chambers and a rotation of the steering shaft in the other direction of rotation causes a reduction of the volume of another one of the pressure chambers;
a hydraulic valve configured to switch in response to predetermined environmental conditions thereby causing a resistance against a further turning of the steering shaft; and
a one-way function permitting inflow of hydraulic fluid into one of the pressure chambers in spite of outflow of hydraulic fluid out of the one of the pressure chambers being blocked as a result of rotation of the steering shaft in a first direction of rotation, said inflow preventing blockage of rotation of the steering shaft in a second direction of rotation opposite the first direction of rotation.

2. The steering stop of claim 1 , wherein the steering handle is a steering wheel.

3. The steering stop of claim 2 , further comprising a piston coupled with the steering wheel so that a turning of the steering wheel causes a movement of the piston in the pressure chambers, said movement causing the reduction of the volume in the pressure chambers wherein the steering wheel is coupled with a hydraulic piston received in the pressure chambers and the reduction of the volume of the pressure chambers.

4. The steering stop of claim 1 , wherein the environmental conditions include at least one member selected from the group consisting of a defined or definable angular position of the steering shaft, an orientation or position of a component of the steering wheel stop, a defined or definable volume of the pressure chambers and a defined or definable inflow into or outflow out of the pressure chambers.

5. The steering stop of claim 1 , further comprising two said hydraulic valves, with one of the two hydraulic valves provided for each of the pressure chambers.

6. The steering stop of claim 5 , wherein the two hydraulic valves are arranged in a common hydraulic valve.

7. The steering stop of claim 1 , further comprising a hydraulic system arranged between the pressure chambers in order to enable a fluid flow from the one pressure chamber into the other pressure chamber depending on the switching position of the hydraulic valve.

8. The steering stop of claim 7 , further comprising a shutoff valve arranged in a fluid circuit of the hydraulic system between the pressure chambers.

9. The steering stop of claim 8 , wherein the shutoff valve is functionally separated from the hydraulic valve.

10. The steering stop of claim 1 , wherein said hydraulic valve is configured to prevent a further outflow of the hydraulic fluid from the first pressure chamber when reaching a threshold value, thereby causing the resistance against a further turning of the steering shaft in the first direction.

11. The steering stop of claim 1 , wherein a decrease of the volume of the one of the pressure chambers resulting from the rotation of the steering shaft corresponds to an identically sized volume increase of the other pressure chamber.

12. The steering stop of claim 1 , further comprising a cylinder including the pressure chambers, and a piston element in engagement with a threaded section of the steering shaft, said piston element being supported torsion stiff against the cylinder so that a rotation of the steering shaft causes a volume change of the pressure chambers.

13. The steering stop of claim 1 , wherein the chambers are part of a hydraulic system which is fluidly separated from a hydraulic system for hydraulically truing the wheels.

Assignees

• Audi Ag

Inventors

• Nagl Martin
• Pfeiffer Ulrich
• Koch Tilo
• Klinger Thomas
• Satzke Anne

Classifications

• B62D5/005

  means for generating torque on steering wheel or input member, e.g. feedback · CPC title

• B62D5/001 Primary

  Mechanical components or aspects of steer-by-wire systems, not otherwise provided for in this maingroup · CPC title