KR20070102804A - An apparatus for compensating steering force in an electric hydraulic power steering system - Google Patents

An apparatus for compensating steering force in an electric hydraulic power steering system Download PDF

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Publication number
KR20070102804A
KR20070102804A KR1020060034460A KR20060034460A KR20070102804A KR 20070102804 A KR20070102804 A KR 20070102804A KR 1020060034460 A KR1020060034460 A KR 1020060034460A KR 20060034460 A KR20060034460 A KR 20060034460A KR 20070102804 A KR20070102804 A KR 20070102804A
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South Korea
Prior art keywords
steering
hydraulic
ecu
motor
sensor
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KR1020060034460A
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Korean (ko)
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이두형
손성재
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현대모비스 주식회사
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Priority to KR1020060034460A priority Critical patent/KR20070102804A/en
Publication of KR20070102804A publication Critical patent/KR20070102804A/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
    • B62D5/10—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle characterised by type of power unit
    • B62D5/14—Rotary motor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W10/00—Conjoint control of vehicle sub-units of different type or different function
    • B60W10/20—Conjoint control of vehicle sub-units of different type or different function including control of steering systems
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
    • B62D5/09—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle characterised by means for actuating valves
    • B62D5/091—Hydraulic steer-by-wire systems, e.g. the valve being actuated by an electric motor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60Y—INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY
    • B60Y2400/00—Special features of vehicle units
    • B60Y2400/30—Sensors
    • B60Y2400/303—Speed sensors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60Y—INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY
    • B60Y2400/00—Special features of vehicle units
    • B60Y2400/30—Sensors
    • B60Y2400/306—Pressure sensors

Abstract

An apparatus for compensating steering force of an electric hydraulic power steering system is provided to prevent a steering wheel from getting hard by increasing RPM of a motor when loss of flow is generated. An apparatus for compensating steering force of an electric hydraulic power steering system includes an ECU(13), a motor(14) receiving signal of a car speed sensor(11) from the ECU, a hydraulic pump(15) driven by the motor so as to supply an operating oil to a steering gear box(16), wherein the operating oil returning from the steering gear box is transferred to an oil reservoir(17) and then supplied to the hydraulic pump, a steering angle sensor(12) detecting a steering angle according to steering and transmitting the detection signal to the ECU, a motor speed sensor(18) receiving signals of the steering angle sensor and the car speed sensor from the ECU and detecting a drive speed of the motor controlled by a compensation signal for driving the motor in accordance with the signals, and a hydraulic sensor(19) detecting a hydraulic pressure of the operating oil transferred to the steering gear box from the hydraulic pump and transmitting the detection signal to the ECU.

Description

전동식 유압 파워스티어링시스템의 조타력 보상 장치 {An apparatus for compensating steering force in an electric hydraulic power steering system} Steering force compensation device of electric hydraulic power steering system {An apparatus for compensating steering force in an electric hydraulic power steering system}

도 1은 종래 EHPS시스템의 조타력 보상 장치 구성도. 1 is a configuration diagram of the steering force compensation device of the conventional EHPS system.

도 2는 본 발명에 따른 EHPS시스템의 조타력 보상 장치 구성도. 2 is a block diagram of a steering force compensation device of the EHPS system according to the present invention.

<도면부호의 설명><Description of Drawing>

1,11 차속센서 2,13 ECU1,11 Vehicle speed sensor 2,13 ECU

3,14 모터 4,15 유압펌프3,14 Motor 4,15 Hydraulic Pump

5,16 스티어링 기어박스 6,17 오일 리저버 탱크5,16 Steering Gearbox 6,17 Oil Reservoir Tank

12 조향각센서 18 모터속도센서12 Steering Angle Sensor 18 Motor Speed Sensor

19 유압센서 19 Hydraulic Sensor

본 발명은 전동식 유압 파워스티어링시스템의 조타력 보상 장치에 관한 것으로서, 보다 구체적으로는 차량의 정지시나 저속상태에서 조타시 유량부족에 의해 핸들이 무거워지는 것을 방지하기 위한 전동식 유압 파워스티어링시스템의 조타력 보상 장치에 관한 것이다. The present invention relates to a steering power compensating device of an electric hydraulic power steering system, and more particularly, to the steering power of an electric hydraulic power steering system for preventing the steering wheel from becoming heavy due to insufficient flow rate when the vehicle is stopped or at a low speed. It relates to a compensation device.

일반적으로, 차량의 파워스티어링장치는 전륜의 조향시 저속주행시에는 가볍고 자연스럽게 큰 각도로 조향되도록 하고, 고속주행시에는 무겁고 자연스럽게 작은 각도로 회전되도록 하여 운전자의 피로감을 덜어주고 안전운전에 도움을 주도록 하기 위한 장치이다. 특히, 조향시스템 중 하나인 유압을 이용한 파워스티어링장치(EHPS)는 엔진 동력이 아닌 모터 구동을 통한 조향장치의 펌프를 구동시켜 운전자의 조타 보조력을 발생시키도록 하는 장치로서, 펌프의 토출 유량은 모터의 회전수(RPM)에 의해 결정되고, 상기 회전수는 차량에서 필요한 유량에 해당하는 속도로 구동된다. In general, the power steering device of the vehicle is designed to lighten and naturally rotate at a large angle at low speed during steering of the front wheel, and to rotate at a small and heavy angle at high speed to reduce driver's fatigue and help safe driving. Device. In particular, the power steering device (EHPS) using hydraulic pressure, which is one of steering systems, is a device that generates a steering assistance force of a driver by driving a pump of a steering device by driving a motor instead of engine power. It is determined by the rotational speed (RPM) of the motor, which is driven at a speed corresponding to the required flow rate in the vehicle.

이러한, 종래 유압을 이용한 파워스티어링장치(EHPS)는 도 1에 도시된 바와 같이, ECU(2)에서 차속센서(1) 신호만을 이용하여 모터(3)의 구동을 통한 유량제어를 이룸으로써 시스템 내 압력변화에 따른 손실유량(내부에서의 누출(leak))에 대한 보상장치가 구비되어 있지 않아 차량의 급조타시, 저속조타시 또는 주차시에 핸들이 무거워져 운전자가 핸들의 조향을 이루는데 불편함을 느끼는 문제점을 갖고 있다. 참고로, 상기 도 1에서, 유압을 발생하는 펌프(4)는 압력 40kgf/cm2 에서 15%정도의 유량 손실이 발생한다. In the conventional hydraulic power steering apparatus (EHPS), as shown in FIG. 1, the ECU 2 controls the flow rate through the driving of the motor 3 using only the vehicle speed sensor 1 signal in the system. It is inconvenient for the driver to steer the steering wheel because the steering wheel becomes heavy during steer, slow steering or parking due to lack of compensation for loss flow (leak from inside) due to pressure change. I have a problem feeling. For reference, in FIG. 1, the hydraulic pressure generating pump 4 generates a flow loss of about 15% at a pressure of 40 kgf / cm 2 .

본 발명은 상기 종래기술의 문제점을 해결하기 위해 제안된 것으로서, 본 발명의 목적은 EHPS 시스템 내 조향각 검출을 위한 조향각센서와 모터의 구동속도 검출을 위한 모터속도센서 및 손실 유량의 판단을 위해 유압을 검출하는 유압센서를 포함하는 구성을 통해 유량 손실 발생시 모터의 구동 회전수를 상승시킴으로써, 차량의 정지시나 저속상태에서 조타시 유량부족에 의해 핸들이 무거워지는 것을 방지토록 한 전동식 유압 파워스티어링시스템의 조타력 보상 장치를 제공하는 것이다. The present invention has been proposed to solve the problems of the prior art, an object of the present invention is to provide a steering angle sensor for detecting the steering angle in the EHPS system and a motor speed sensor for detecting the driving speed of the motor and the hydraulic pressure to determine the loss flow rate By including a hydraulic sensor to detect, the drive rotation speed of the motor is increased when a flow loss occurs, thereby preventing the steering wheel from becoming heavy due to insufficient flow rate when the vehicle is stopped or at low speeds. It is to provide an inertial compensation device.

상기 목적을 이루기 위한, 본 발명에 따른 차속센서 신호를 ECU에서 입력받은 후 상기 ECU의 제어에 따른 모터의 구동을 통한 유압펌프의 작동으로 작동유가 스티어링기어박스로 보내지고, 상기 스티어링기어박스에서 리턴되는 작동유가 오일 리저버 탱크측으로 이송된 후 다시 유압펌프측으로 공급되는 전동식 유압 파워스티어링시스템에서 손실된 유량만큼 상기 모터의 구동 회전수를 보상하기 위한 장치는, To achieve the above object, after receiving the vehicle speed sensor signal according to the present invention from the ECU, the operating oil is sent to the steering gear box by the operation of the hydraulic pump through the driving of the motor according to the control of the ECU, the return from the steering gear box Apparatus for compensating the drive rotational speed of the motor by the flow rate lost in the electric hydraulic power steering system that is supplied to the hydraulic reservoir side after the hydraulic oil is transferred to the oil reservoir tank side,

차량의 핸들 조향에 따른 조향각을 검출한 후 검출된 신호를 상기 ECU로 전송하는 조향각센서와, A steering angle sensor for detecting a steering angle according to steering of a vehicle and transmitting the detected signal to the ECU;

상기 조향각센서와 차속센서 신호를 ECU에서 입력받은 후 그에 상응하는 모터 구동을 위한 보상신호에 따라 구동 제어되는 모터의 구동속도를 검출하여 상기 ECU로 전송하는 모터속도센서와, A motor speed sensor which receives the steering angle sensor and the vehicle speed sensor signal from the ECU and detects a driving speed of a motor controlled to be driven according to a compensation signal for driving the motor, and transmits the same to the ECU;

상기 유압펌프로부터 상기 스티어링기어박스로 이송되는 작동유의 유압을 검출하여 상기 ECU로 전송하는 유압센서를 포함하는 것을 특징으로 한다. And a hydraulic pressure sensor for detecting the hydraulic pressure of the hydraulic oil transferred from the hydraulic pump to the steering gear box and transmitting the hydraulic pressure to the ECU.

이하, 도면을 참조하여 본 발명에 따른 바람직한 실시예를 설명한다. Hereinafter, with reference to the drawings will be described a preferred embodiment according to the present invention.

본 실시예에 따른 EHPS시스템의 조타력 보상 장치 구성을 도 2를 참조하여 설명한다. The steering force compensating device configuration of the EHPS system according to the present embodiment will be described with reference to FIG. 2.

도 2에 도시된 바와 같이, 본 실시예에 따른 차속센서(11) 신호를 ECU(13)에서 입력받은 후 상기 ECU의 제어에 따른 모터(14)의 구동을 통한 유압펌프(15)의 작동으로 작동유가 스티어링기어박스(16)로 보내지고, 상기 스티어링기어박스(16)에서 리턴되는 작동유가 오일 리저버 탱크(17)측으로 이송된 후 다시 유압펌프(15)측으로 공급되는 전동식 유압 파워스티어링시스템에서 시스템상의 내부 부하 증가에 의해 손실되는 유량만큼 상기 모터(14)의 구동 회전수를 보상함으로써, 운전자의 급조향 또는 저속조향 또는 차량 주차시 핸들 조향이 무거워짐을 방지하기 위한 장치 구성은, As shown in FIG. 2, after the vehicle speed sensor 11 signal according to the present embodiment is input from the ECU 13, the hydraulic pump 15 is operated by driving the motor 14 under the control of the ECU. In the electric hydraulic power steering system in which hydraulic oil is sent to the steering gear box 16 and the hydraulic oil returned from the steering gear box 16 is transferred to the oil reservoir tank 17 and then supplied to the hydraulic pump 15 side. By compensating the drive rotational speed of the motor 14 by the flow rate lost by the increase of the internal load on the bed, the device configuration for preventing the steering of the driver from heavy steering or slow steering or vehicle parking becomes heavy,

차량의 핸들 조향에 따른 조향각을 검출한 후 검출된 신호를 상기 ECU(13)로 전송하는 조향각센서(12)와, A steering angle sensor 12 for detecting a steering angle according to steering of a vehicle and transmitting the detected signal to the ECU 13;

상기 조향각센서(12)와 차속센서(11) 신호를 ECU(13)에서 입력받은 후 그에 상응하는 모터(14) 구동을 위한 보상신호에 따라 구동 제어되는 모터의 구동속도를 검출하여 상기 ECU로 전송하는 모터속도센서(18)와, After receiving the steering angle sensor 12 and the vehicle speed sensor 11 signals from the ECU 13, the driving speed of the motor controlled by the driving signal is detected and transmitted to the ECU according to a compensation signal for driving the corresponding motor 14. Motor speed sensor 18,

상기 유압펌프(15)로부터 상기 스티어링기어박스(16)로 이송되는 작동유의 유압을 검출하여 상기 ECU(13)로 전송하는 유압센서(19)를 포함하여 구성된다. It comprises a hydraulic sensor 19 for detecting the hydraulic pressure of the hydraulic oil transferred from the hydraulic pump 15 to the steering gear box 16 to the ECU (13).

상기에서, 본 실시예에 따른 ECU(13) 내에는 상기 유압센서(19)를 통해 검출된 유압 데이터를 비교하기 위한 기준 유압 데이터가 테이블로 저장되어 있다. In the above, in the ECU 13 according to the present embodiment, reference hydraulic data for comparing hydraulic pressure data detected through the hydraulic sensor 19 is stored in a table.

상기와 같은 장치구성을 갖는, 본 실시예에 따른 EHPS시스템의 조타력 보상 장치의 동작을 도 2를 참조하여 설명한다. The operation of the steering force compensating device of the EHPS system according to the present embodiment having the above-described device configuration will be described with reference to FIG.

도 2에서 보는 바와 같이, ECU(13)에서는 차속센서(11)와 조향각센서(12) 신호를 입력받아 모터의 구동을 보상 제어하는데, 이와 동시에 상기 ECU(13)에서는 모터속도센서(18) 및 유압센서(19) 신호를 입력받아 현 모터의 구동 회전수 판단 및 유압펌프(15)측에서 스티어링기어박스(16)측으로 인가되는 고압호스 내의 유압을 판단한다. As shown in FIG. 2, the ECU 13 receives signals of the vehicle speed sensor 11 and the steering angle sensor 12 to compensate and control the driving of the motor. At the same time, the ECU 13 includes the motor speed sensor 18 and In response to the signal of the hydraulic sensor 19, the driving speed of the current motor is determined and the hydraulic pressure in the high pressure hose applied from the hydraulic pump 15 to the steering gear box 16 is determined.

상기 유압 판단결과, 현 차량동작상태에 따른 ECU(13) 내 기설정된 기준 데이터에 미치지 못하는 경우 유량의 누설로 판단하여, 누설된 유량만큼 보상을 이루기 위해 모터(14)의 구동 회전수를 증대시켜 그에 따른 유압펌프(15)의 작동으로 유량부족에 의한 운전자의 핸들 조향시 핸들이 무거워지는 것을 방지할 수 있도록 한 것이다. 즉, 상기에서와 같이, 본 실시예에서는 차량의 주행상태 및 운전자의 조향상태에 따라 조향상황에 부합하는 최적의 운전조건을 제공할 수 있도록 한 것이다. As a result of the determination of the oil pressure, if the ECU 13 does not reach the preset reference data according to the current vehicle operating state, it is determined that the flow rate is leaked, and the drive rotation speed of the motor 14 is increased to compensate for the leaked flow rate. Accordingly, the operation of the hydraulic pump 15 is to prevent the handle from becoming heavy when steering the steering wheel of the driver due to insufficient flow. That is, as described above, according to the present embodiment, it is possible to provide an optimal driving condition corresponding to the steering situation according to the driving state of the vehicle and the steering state of the driver.

본 발명의 기술적 범위를 해석함에 있어서는, 상기에서 설명된 실시예에 한정하여 해석되어서는 아니 되며, 본 발명의 기술적 범위는 특허청구범위에 기재된 사항의 합리적 해석에 의해 결정되어져야 한다. In interpreting the technical scope of the present invention, it should not be construed as being limited to the embodiments described above, and the technical scope of the present invention should be determined by reasonable interpretation of the matters described in the claims.

본 발명의 전동식 유압 파워스티어링시스템의 조타력 보상 장치에 따르면, 시스템 내 과부하에 의한 유량 손실에 따른 모터의 구동 보상을 통해 운전자의 조향시 핸들이 무거워지는 것을 방지함으로써 최적의 운전조건을 제공할 수 있는 효과를 갖는다. According to the steering force compensating device of the electric hydraulic power steering system of the present invention, it is possible to provide the optimum operating conditions by preventing the steering wheel from becoming heavy when steering the driver through the drive compensation of the motor according to the flow loss due to the overload in the system. Has the effect.

Claims (2)

차속센서 신호를 ECU에서 입력받은 후 상기 ECU의 제어에 따른 모터의 구동을 통한 유압펌프의 작동으로 작동유가 스티어링기어박스로 보내지고, 상기 스티어링기어박스에서 리턴되는 작동유가 오일 리저버 탱크측으로 이송된 후 다시 유압펌프측으로 공급되는 전동식 유압 파워스티어링시스템에 있어서, After receiving the vehicle speed sensor signal from the ECU, the hydraulic oil is sent to the steering gear box by the operation of the hydraulic pump by driving the motor according to the control of the ECU, and the hydraulic oil returned from the steering gear box is transferred to the oil reservoir tank side. In the electric hydraulic power steering system supplied to the hydraulic pump side, 차량의 핸들 조향에 따른 조향각을 검출한 후 검출된 신호를 상기 ECU로 전송하는 조향각센서와, A steering angle sensor for detecting a steering angle according to steering of a vehicle and transmitting the detected signal to the ECU; 상기 조향각센서와 차속센서 신호를 ECU에서 입력받은 후 그에 상응하는 모터 구동을 위한 보상신호에 따라 구동 제어되는 모터의 구동속도를 검출하여 상기 ECU로 전송하는 모터속도센서와, A motor speed sensor which receives the steering angle sensor and the vehicle speed sensor signal from the ECU and detects a driving speed of a motor controlled to be driven according to a compensation signal for driving the motor, and transmits the same to the ECU; 상기 유압펌프로부터 상기 스티어링기어박스로 이송되는 작동유의 유압을 검출하여 상기 ECU로 전송하는 유압센서를 포함하는 것을 특징으로 하는 전동식 유압 파워스티어링시스템의 조타력 보상 장치. Steering force compensation device of the electric hydraulic power steering system, characterized in that it comprises a hydraulic sensor for detecting the hydraulic pressure of the hydraulic fluid transferred from the hydraulic pump to the steering gear box to the ECU. 청구항 1에 있어서, The method according to claim 1, 상기 ECU 내에는 상기 유압센서를 통해 검출된 유압 데이터를 비교하기 위한 기준 유압 데이터가 테이블로 저장되어 있는 것을 특징으로 하는 전동식 유압 파워스티어링시스템의 조타력 보상 장치. Steering force compensation device of the electric hydraulic power steering system, characterized in that the reference hydraulic data for comparing the hydraulic data detected by the hydraulic sensor in the ECU is stored in a table.
KR1020060034460A 2006-04-17 2006-04-17 An apparatus for compensating steering force in an electric hydraulic power steering system KR20070102804A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103707923A (en) * 2013-12-20 2014-04-09 华南理工大学 Two-speed hydraulic steering gear
CN103707921A (en) * 2013-12-20 2014-04-09 华南理工大学 Double-speed hydraulic steering amplification system of car

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103707923A (en) * 2013-12-20 2014-04-09 华南理工大学 Two-speed hydraulic steering gear
CN103707921A (en) * 2013-12-20 2014-04-09 华南理工大学 Double-speed hydraulic steering amplification system of car
CN103707923B (en) * 2013-12-20 2016-05-04 华南理工大学 A kind of dual-speed hydraulic steering gear

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