US 9,932,068 B2Granted

Integrated power steering system for front and rear wheels of vehicle and control method thereof

AssigneeHyundai Motor Company

InventorSeung Hyun Oh

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Abstract

A power steering system of a vehicle and a control method are provided. The system includes a main hydraulic motor that receives engine power and generates a hydraulic pressure and an auxiliary hydraulic motor that generates a hydraulic pressure. A front wheel steering cylinder receives hydraulic pressure and generates power for steering front wheels and auxiliary steering of a driver. A rear wheel steering cylinder receives hydraulic pressure and generates power for steering rear wheels. An integrated control valve connected to the hydraulic motors and the steering cylinders through hydraulic pressure pipelines, and adjusts the hydraulic pressure of a main hydraulic motor to supply the pressure to the front wheel steering cylinder and adjusts the hydraulic pressure generated of the auxiliary hydraulic motor to supply the pressure to the front or rear wheel steering cylinder.

Claims7

Dependent claims

An integrated power steering system for front and rear wheels of a vehicle, comprising:

a main hydraulic pump configured to receive power of an engine to be driven, and generate a hydraulic pressure;
an auxiliary hydraulic pump configured to generate a hydraulic pressure;
a front wheel steering cylinder configured to receive hydraulic pressure and generate power for steering of front wheels and auxiliary steering of a driver;
a rear wheel steering cylinder configured to receive hydraulic pressure and generate power for steering of rear wheels;
an integrated control valve connected to the hydraulic pumps and the steering cylinders through hydraulic pressure pipelines, and configured to adjust the hydraulic pressure generated by the main hydraulic pump to supply the adjusted hydraulic pressure to the front wheel steering cylinder and adjust the hydraulic pressure generated by the auxiliary hydraulic pump to supply the adjusted hydraulic pressure to any one of the front wheel steering cylinder and the rear wheel steering cylinder;
a controller configured to operate the auxiliary hydraulic pump and the integrated control valve to supply the hydraulic pressure generated by the main hydraulic pump to the front wheel steering cylinder and to supply the hydraulic pressure generated by the auxiliary hydraulic pump to any one of the front wheel steering cylinder and the rear wheel steering cylinder when the steering wheel is manipulated;
and
a speed sensor configured to detect a driving speed of the vehicle,
wherein when the main hydraulic pump is in a normal state and the vehicle speed detected by the speed sensor while the steering wheel is manipulated is a reference speed or less, the controller is configured to operate the auxiliary hydraulic pump to the front wheel steering cylinder and supply the hydraulic pressure generate by the auxiliary hydraulic pump to the rear wheel steering cylinder.

6 more elements

A control method of an integrated power steering system for front and rear wheels comprising:

a main hydraulic pump configured to receive power of an engine to be driven, and generate a hydraulic pressure;
an auxiliary hydraulic pump configured to generate a hydraulic pressure;
a front wheel steering cylinder configured to receive hydraulic pressure and generate power for steering of front wheels and auxiliary steering of a driver;
a rear wheel steering cylinder configured to receive hydraulic pressure and generate power for steering of rear wheels;
an integrated control valve connected to the hydraulic pumps and the steering cylinders through hydraulic pressure pipelines;
and a controller configured to operate the auxiliary hydraulic pump and the integrated control valve, the control method comprising:
determining, by the controller, whether the main hydraulic pump fails;
in response to detecting the failure, operating, by the controller, the integrated control valve to supply the hydraulic pressure generated by the auxiliary hydraulic pump to the front wheel steering cylinder while the steering wheel is manipulated;
and
when the main hydraulic pump is in a normal state, adjusting, by the controller, the hydraulic pressure generated by the main hydraulic pump to supply the adjusted hydraulic pressure to the front wheel steering cylinder, and adjusting the hydraulic pressure generated by the auxiliary hydraulic pump to supply the adjusted hydraulic pressure to the rear wheel steering cylinder while the steering wheel is manipulated,
wherein when the main hydraulic pump is in the normal state and the speed of the vehicle is a reference speed or less while steering wheel is manipulated, the hydraulic pressure generated by the main hydraulic pump is adjusted to supply the adjusted hydraulic pressure to the front wheel steering cylinder, and the hydraulic pressure generated by the auxiliary hydraulic pump is adjusted to supply the adjusted hydraulic pressure to the rear wheel steering cylinder.

8 more elements

Dependencies are inferred from the claim text.

Facts

Application: 14/960,995Filed 7 Dec 2015
Priority: KR 10-2015-013012215 Sep 2015
Published: US 2017/0072997 A116 Mar 2017
Granted: 3 Apr 2018
Term ends: Not estimatedThe source records don’t support an estimate.

Classification8 codes

B62D 5/063
Details, component parts: pump driven by vehicle engine
B62D 5/09
Fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle: characterised by means for actuating valves
B62D 7/144
Specially adapted for particular vehicles, e.g. tractors, carts, earth-moving vehicles, trucks: for vehicles with more than two axles
B62D 7/146
The pivotal axes being situated in more than one plane transverse to the longitudinal centre line of the vehicle, e.g. all-wheel steering:…