KR20170029332A - Hybrid steering device - Google Patents

Abstract

The present invention relates to a hybrid steering device capable of simplifying a structure of electric hydraulic power steering using an electric oil pump and increasing efficiency of electronic control. The hybrid steering device comprises: a piston disposed in a piston housing and having an outer gear formed on an outer surface thereof; a pitman arm having a sector gear engaged with the outer gear and rotated by the movement of the piston; a tie rod steering a driving wheel by moving the pitman arm; and a hydraulic control valve controlling an oil pressure supplied to a first chamber and a second chamber of the piston housing so that the piston is moved in the piston housing. The hydraulic control valve includes a valve housing having a space formed therein and including a first port connected to a first chamber, a second port connected to a second chamber, and a supply port receiving an oil pressure formed at each longitudinal set position in the space; a spline disposed in the space and connecting the supply port with the first port or connecting the supply port with the second port depending on position; and an electronic driving unit disposed at one side or the other side of the valve housing and disposed to push or pull the spline by electric energy.

Description

[0001] HYBRID STEERING DEVICE [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates generally to a hybrid steering apparatus used in a large vehicle, and more particularly, to a hybrid steering apparatus that uses a steering motor and hydraulic pressure to steer a wheel.

Generally, the steering apparatus requires a hydraulic pump by using the hydraulic pressure as the steering assist force, and the hydraulic pump is driven by the engine, so that the engine driving force is inevitably lost.

The loss of the engine driving force as described above results in a decrease in fuel consumption. Therefore, if the degree of loss of the engine driving force through the steering device is reduced, the fuel efficiency can be improved accordingly.

As an example of the improvement of fuel economy, there is a hydraulic steering apparatus which is equipped with a hydraulic pump driven by an engine but can reduce the loss of the engine driving force by reducing the pipe flow resistance of the hose or reducing the pump flow rate during idling.

However, the improvement of fuel economy through the hydraulic steering system has a fundamental limitation that the effect of the hydraulic pump driven by the engine is small. To overcome this fundamental limitation, the hydraulic pump driven by the engine must be eliminated.

[0003] As a steering apparatus for eliminating a hydraulic pump driven by an engine in accordance with the above requirements, there has been proposed a steering apparatus that uses an MDPS (Motor Driven Power Steering) in which an electric motor is used, or an EHPS Power Steering).

 Therefore, the MDPS or EHPS is used as a steering apparatus of a hybrid passenger vehicle in which improvement of fuel economy is indispensable. However, improvement of fuel efficiency is an item that must be pursued not only in passenger cars but also in commercial vehicles. For this purpose, if the hydraulic pump using the driving force of the engine is deleted and the MDPS or EHPS can be used as a steering device, Performance can be greatly increased.

However, steering systems using MDPS or EHPS may be suitable for passenger vehicles requiring a steering capacity of about 13 KN due to their limited steering capacity, but they are not suitable for medium and large commercial vehicles requiring steering capacities of about 50 KN to 190 KN There are fundamental limitations that are not appropriate.

Accordingly, when the MDPS steering apparatus or the EHPS steering apparatus is applied to a commercial vehicle alone in order to improve the fuel efficiency, the shortage of the steering capacity must be solved first.

Therefore, research has been conducted on a hybrid steering system that uses an MDPS using a steering motor and an EHPS using a hydraulic pressure through a motor steering torque output from the MDPS through a driver's steering torque input through a steering wheel Which simplifies the overall structure and improves the efficiency of electronic control.

It is an object of the present invention to provide a hybrid steering apparatus capable of simplifying the structure of an electric hydraulic power steering (EHPS) using an electric oil pump and improving the efficiency of electronic control.

As described above, the hybrid steering apparatus according to the embodiment of the present invention includes a piston disposed in a piston housing, a piston having an outer gear formed on an outer surface thereof, a sector gear engaged with the outer gear, And a hydraulic control valve for controlling the hydraulic pressure supplied to the first chamber and the second chamber of the piston housing so that the piston moves within the piston housing, Wherein the hydraulic control valve includes a first port formed in the space therein and connected to the first chamber in the space, a second port connected to the second chamber, and a supply port receiving hydraulic pressure, A valve housing formed in a longitudinally set position, a valve housing disposed in the space, Connected and are arranged to the supply ports on one side or the other side of the spool, the valve housing being arranged to couple with the second port can include an electrical drive unit which is arranged to push or pull the spool by the electrical energy.

The worm gear is disposed in the piston so as to be rotated by the steering force of the driver and is fastened to the piston. The piston is arranged to move in a predetermined direction by the rotation direction of the worm gear and the hydraulic pressure supplied to the first and second chambers .

An oil pump that pumps the hydraulic pressure to the supply port, and an oil reservoir that contains the steering oil pumped by the oil pump.

The valve housing may be provided with a return port for receiving hydraulic pressure returned from the first chamber or the second chamber through the first port or the second port and returning the hydraulic pressure to the oil reservoir.

The first port and the second port may be formed on both sides with a predetermined distance based on the supply port.

A return port is formed in the valve housing for receiving hydraulic pressure returned from the first chamber or the second chamber through the first port or the second port and returning the hydraulic pressure to the oil reservoir, And may be formed on the opposite side at a position corresponding to the supply port.

Wherein the first supply port and the second supply port are connected to each other, and the supply port and the first port are connected to each other by a spool groove, You can connect.

And the supply port is connected to the first port through the spool groove when the spool moves to the first port with respect to the supply port by the first electromagnetic driving unit, And can be transmitted to the return port through the spool in the radial direction.

Wherein the supply port is connected to the second port through the spool groove when the spool moves to the second port with respect to the supply port by the electromagnetic driver, And can be transmitted to the return port through the spool in the radial direction.

The electromagnetic driving unit may be of an electromagnet type that moves the spool using the force of an electromagnet.

A first torque sensor that senses a steering torque transmitted to a first steering shaft that transmits a driver's steering force and a steering motor that is arranged to rotate a second steering shaft in accordance with a torque sensed by the first torque sensor The worm gear formed at the end of the second steering shaft can be inserted into the piston and fastened.

A second torque sensor for sensing a steering force input to the second steering shaft by the steering motor, and a second torque sensor for controlling the steering motor in response to a signal sensed by the first torque sensor, And a control unit for controlling the electromagnetic driving unit in accordance with the signal.

The steering motor may be arranged to rotate the second steering shaft through the structure of the worm gear and the worm wheel gear.

The oil pump may be of the electric type using a rotational force generated by electric energy.

The electromagnetic driving part may include first and second electromagnetic driving parts disposed at both ends of the valve housing and arranged to push or pull both ends of the spool.

According to an aspect of the present invention, there is provided a hydraulic control apparatus for an internal combustion engine in which a hydraulic control valve is not provided on a steering shaft and an oil pressure control valve is disposed separately. By electronically controlling a hydraulic pressure control valve in accordance with a torque signal sensed by a torque sensor, The structure of the control valve can be simplified, the steering performance can be improved, the weight can be reduced, and the efficiency of the steering control can be improved.

1 is a schematic configuration diagram of a steering system according to an embodiment of the present invention.
2 is a partial cross-sectional view showing the operating structure of the hydraulic control valve and the piston in the steering system according to the embodiment of the present invention.
3 is a partial cross-sectional view showing a first operating state of the hydraulic control valve according to the embodiment of the present invention.
4 is a partial cross-sectional view showing a second operating state of the hydraulic control valve according to the embodiment of the present invention.
5 is a partial cross-sectional view showing a third operating state of the hydraulic control valve according to the embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the embodiment of the present invention, the steering motor for applying the steering force and the control unit for controlling the steering motor set the neutral position of the rack, thereby reducing the load on the operator and increasing the accuracy.

Hereinafter, a configuration and a method for achieving the above-mentioned effects will be described, and known configurations will be described with reference to known technologies, and only cold storage essential for understanding the present invention will be described.

1 is a schematic configuration diagram of a steering system according to an embodiment of the present invention.

1, the steering system includes a steering wheel 100, a first steering shaft 112, a first torque sensor 110, a steering motor 120, a control unit 10, a second steering shaft 135, The second torque sensor 130, the piston 140, the piston housing 150, the hydraulic control valve 160, the oil pump 170, the oil reservoir 180, the sector gear 190, A drag link 194, a spindle arm 196, a tie rod 198, and a drive wheel 199.

When the driver operates the steering wheel 100, the first steering shaft 112 rotates. The first torque sensor 110 disposed on the first steering shaft 112 senses the steering torque and transmits the steering torque to the controller 10.

The controller 10 operates the steering motor 120 in accordance with the torque signal sensed by the first torque sensor 110 to rotate the second steering shaft 135. The second torque sensor 130 installed on the second steering shaft 135 senses an input steering torque and transmits the steering torque to the controller 10.

The control unit 10 controls the hydraulic control valve 160 according to a torque signal sensed by the second torque sensor 130 to move the piston 140 disposed in the piston housing 150.

The oil pump 170 is electrically driven to pump the oil contained in the oil reservoir 180 to the hydraulic control valve 160. The front end of the second steering shaft 135 is connected to the And the distal end of the first steering shaft 112 and the piston 140 are screwed together.

The piston 140 moves reciprocally according to the rotational position of the second steering shaft 135. The hydraulic pressure control valve 160 uses the hydraulic pressure to move the piston 140.

The sector gear 190 has a structure that meshes with a gear formed on the outer circumferential surface of the piston 140 and rotates in accordance with the movement of the piston 140. The rotation of the sector gear 190 is transmitted to the fit- The drag link 194, the spindle arm 196 and the tie rod 198, and the tie rod 198 steers the drive wheels 199 while moving left and right.

2 is a partial cross-sectional view showing the operating structure of the hydraulic control valve and the piston in the steering system according to the embodiment of the present invention.

2, the second steering shaft 135 is disposed to pass through a central portion of the piston 140, a worm gear 210 is formed on an outer circumferential surface of one side of the second steering shaft 135, The inner circumferential surface of the worm gear 140 is coupled with the worm gear 210 through the ball 215. Accordingly, when the second steering shaft 135 rotates, the piston 140 moves left and right.

The piston 140 is disposed inside the piston housing 150 and the sector gear 190 is gear-engaged with the outer surface of the piston 140. Accordingly, when the piston 140 moves, the sector gear 190 rotates to steer the driving wheel 199.

In the piston housing 150, a first chamber 220A is formed on the right side of the piston 140, and a second chamber 220B is formed on the left side of the piston 140. The hydraulic pressure control valve 160 controls the hydraulic pressure supplied to the first chamber 220A and the second chamber 220B to move the piston 140 right or left.

The hydraulic control valve 160 includes a valve housing 320, a spool 300, a first electromagnetic driving part 240 and a second electromagnetic driving part 250. The hydraulic control valve 160 includes a return port 230C, ), A second port 230B, and a supply port 230P are formed.

The oil pump 170 pumps the oil through the supply port 230P and the oil reservoir 180 stores oil to be pumped by the oil pump 170 and the first port 230A Is connected to the first chamber 220A of the piston housing 150 and the second port 230B is connected to the second chamber 220B of the piston housing 150. [ The return port 230C is connected to the oil reservoir 180.

The sphygmomanometer according to any one of claims 1 to 3, wherein the spool (300) is disposed movably through a central portion of the valve housing (320) (240, 250). The first and second electromagnetic driving units 240 and 250 may push or pull the spool 300 using an electromagnet.

The hydraulic pressure supplied to the supply port 230P is supplied to the first port 230A or the second port 230B according to the position of the spool 300 to control the movement of the piston 140 have.

When the oil supplied to the supply port 230P is supplied to the first chamber 220A through the first port 230A, the oil in the second chamber 220B flows into the second port 230B And returned to the oil reservoir 180 through the return port 230C.

3 is a partial cross-sectional view showing a first operating state of the hydraulic control valve according to the embodiment of the present invention.

3, the supply port 230P is formed at an upper center portion of the valve housing 320, and the first and second ports 230A and 230B are provided on both sides of the supply port 230P And the return port 230C is formed at a lower center portion of the valve housing 320 at a position corresponding to the supply port 230P.

The spool 300 is formed with a spool groove 310 at a position corresponding to the supply port 230P and the oil supplied to the supply port 230P flows through the spool 310 into the first port 230A and the second port 230B. In addition, the first and second return holes 332 and 330 are formed on both sides of the spool groove 310, from the top to the bottom.

The oil supplied to the supply port 230P in a state in which the spool 300 is moved to the right by the first electromagnetic driver 240 is transmitted through the spool 310 and the first port 230A to the first chamber 220A.

The oil returned from the second chamber 220B to the second port 230B is circulated to the oil reservoir 180 through the second return hole 330 and the return port 230C, The drive wheel 199 can be steered to the right.

4 is a partial cross-sectional view showing a second operating state of the hydraulic control valve according to the embodiment of the present invention.

4, when the spool 300 is moved to the left by the second electromagnetic driver 250, the oil supplied to the supply port 230P flows through the spool 310 and the second port And is supplied to the second chamber 220B through the second chamber 230B.

The oil returned from the first chamber 220A to the first port 230A is circulated to the oil reservoir 180 through the first return hole 332 and the return port 230C, The drive wheel 199 can be steered to the left.

5 is a partial cross-sectional view showing a third operating state of the hydraulic control valve according to the embodiment of the present invention. The state of Fig. 5 is compared with Fig.

5, a portion of the oil supplied through the supply port 230P flows through the first port 230A through the spool groove 310 while the spool 300 is not completely moved to the right, And the remainder is circulated to the oil reservoir 180 through the second return hole 330. Accordingly, the hydraulic pressure is regulated according to the amount of movement of the spool 300 to control the steering force.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, And all changes to the scope that are deemed to be valid.

10: control unit 100: steering wheel
110: first torque sensor 112: first steering shaft
120: Steering motor 130: Second torque sensor
135: second steering shaft 140: piston
150: piston housing 160: hydraulic control valve
170: Oil pump 180: Oil reservoir
190: sector gear 192:
194: Drag link 196: Spindle arm
198: tie rod 199: drive wheel
210: Worm gear 215: Ball
220A: first chamber 220B: second chamber
240: first electromagnetic driving part 250: second electromagnetic driving part
230A: first port 230B: second port
230C: return port 320: valve housing
310: spool groove 300: spool
332: first return hole 330: second return hole

Claims (15)

A piston disposed in the piston housing and having an outer gear formed on an outer surface thereof;
A foot gear formed with a sector gear engaged with the outer gear, and rotated according to the movement of the piston;
A tie rod that moves by the fittane-like rock to steer the drive wheel; And
A hydraulic control valve for controlling the hydraulic pressure supplied to the first chamber and the second chamber of the piston housing so that the piston moves within the piston housing; Lt; / RTI >
The hydraulic control valve includes:
A first port connected to the first chamber in the space, a second port connected to the second chamber, and a supply port receiving hydraulic pressure are formed in a longitudinally set position, housing;
A spool disposed in the space and arranged to couple the supply port with the first port or to connect the supply port with the second port depending on the position;
An electromagnetic driving part disposed at one side or the other side of the valve housing and arranged to push or pull the spool by electric energy;
And a steering angle sensor for detecting steering angle of the steering wheel. The method of claim 1,
The worm gear, which is arranged to rotate by the driver's steering force, is inserted into the piston and is fastened to the piston,
Wherein the piston is arranged to move in a direction set by the rotational direction of the worm gear and the hydraulic pressure supplied to the first and second chambers. The method of claim 1,
An oil pump for pumping hydraulic pressure to the supply port; And
The oil reservoir containing the steering oil pumped by the oil pump;
And a steering angle sensor for detecting steering angle of the steering wheel. 4. The method of claim 3,
Wherein the valve housing is formed with a return port for receiving hydraulic pressure returned from the first chamber or the second chamber through the first port or the second port and returning the hydraulic pressure to the oil reservoir. . The method of claim 1,
Wherein the first port and the second port are formed on both sides with a predetermined distance based on the supply port. The method of claim 1,
Wherein the valve housing is formed with a return port for receiving hydraulic pressure returned from the first chamber or the second chamber through the first port or the second port and returning the hydraulic pressure to the oil reservoir,
And the return port is formed on a side opposite to the position corresponding to the supply port. The method of claim 6,
Wherein the first supply port and the second supply port are connected to each other, and the supply port and the first port are connected to each other by a spool groove, And the steering wheel is connected to the steering wheel. 8. The method of claim 7,
And the supply port is connected to the first port through the spool groove when the spool moves to the first port with respect to the supply port by the first electromagnetic driving unit, Wherein the spool passes through the spool in the radial direction and is transmitted to the return port. 8. The method of claim 7,
Wherein the supply port is connected to the second port through the spool groove when the spool moves to the second port with respect to the supply port by the electromagnetic driver, Wherein the spool is transmitted through the return port through the spool in the radial direction. The method of claim 1,
Wherein the electromagnetic driving unit is of an electromagnet type that moves the spool using the force of the electromagnet. The method of claim 1,
A first torque sensor for sensing a steering torque transmitted to a first steering shaft that transmits a driver's steering force; And
A steering motor disposed to rotate a second steering shaft in accordance with a torque sensed by the first torque sensor; Lt; / RTI >
And a worm gear formed at an end of the second steering shaft is inserted into the piston and fastened. 12. The method of claim 11,
A second torque sensor for sensing a steering force input to the second steering shaft by the steering motor; And
A control unit for controlling the steering motor in accordance with a signal sensed by the first torque sensor and controlling the electromagnetic driving unit according to a signal sensed by the second torque sensor;
And a steering angle sensor for detecting steering angle of the steering wheel. The method of claim 12,
Wherein the steering motor is arranged to rotate the second steering shaft through a structure of a worm gear and a worm wheel gear. 4. The method of claim 3,
Wherein the oil pump is an electric type using a rotational force generated by electric energy. The method of claim 1,
Wherein the electromagnetic driving part includes first and second electromagnetic driving parts disposed at both ends of the valve housing and arranged to push or pull both ends of the spool.

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