Electro-hydraulic power steering apparatus for environment-friendly vehicle and method of controlling the same

Patent metadata

Field	Value
Publication number	US-9381937-B2
Application number	US-201314145122-A
Country	US
Kind code	B2
Filing date	Dec 31, 2013
Priority date	Aug 9, 2013
Publication date	Jul 5, 2016
Grant date	Jul 5, 2016

Abstract

An electro-hydraulic power steering apparatus for an environment-friendly vehicle and a method of controlling the same is provided. In particular, a gear box assists in a steering force of a steering wheel, and a reservoir tank stores hydraulic oil therein. An electro-hydraulic power pump pumps the hydraulic oil via an electric motor to supply the hydraulic oil to the gear box. A first valve is mounted to a hydraulic line through which the hydraulic oil flows from the electro-hydraulic power pump to the gear box, and a second valve is mounted to a hydraulic line through which the hydraulic oil returns from the gear box to the reservoir tank.

First claim

What is claimed is:

1. A method of controlling an electro-hydraulic power steering apparatus for an environment-friendly vehicle, the method comprising the steps of:
determining, by a controller, whether a steering angle of a steering wheel has been turned at or beyond a particular angle;
in response to determining that the steering angle is at or beyond the particular angle, determining, by the controller, whether the steering angle has changed within a particular time period;
controlling, by the controller, a first valve mounted within a hydraulic oil line through which hydraulic oil flows from an electro-hydraulic power pump to a gear box and a second valve mounted to a hydraulic line through which the hydraulic oil returns from the gear box to a reservoir tank to be closed, when the steering angle has not changed within the particular time period;
turning off, by the controller, the electro-hydraulic power pump together with controlling the first valve and the second valve to be closed; and
controlling the first valve and the second valve to be opened when the steering angle has changed.

2. The method of claim 1 , further comprising the step of:
turning on, by the controller, the electro-hydraulic power pump after the first valve and the second valve are controlled to be opened.

Assignees

• Hyundai Motor Co Ltd

Inventors

• Choi Young Seol

Classifications

• B62D5/06 Primary

  fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle · CPC title

• B62D5/065 Primary

  characterised by specially adapted means for varying pressurised fluid supply based on need, e.g. on-demand, variable assist · CPC title

• B62D6/08

  responsive only to {driver} input torque · CPC title

• B62D6/00

  Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits (means for initiating a change in direction B62D1/00; steering valves B62D5/06; combined with means for inclining the vehicle body or wheels on bends B62D9/00) · CPC title

• B62D5/08

  characterised by type of {steering} valve used (valves in general F16K) · CPC title