KR20220094449A - Hydraulic power steering apparatus - Google Patents

Abstract

Provided is a hydraulic power steering device accurately switches driving modes when switching a mode from a manual driving mode to an automatic driving mode or switching the mode from the automatic driving mode to the manual driving mode. To this end, according to the present invention, the hydraulic power steering device comprises: a first automatic steering operation valve supplying hydraulic pressure provided from an automatic steering on-off valve to one end of an automatic steering valve when the automatic steering on-off valve turns on the automatic driving mode to move a spool of the automatic steering valve to the other end of the automatic steering valve to change a flow passage of the automatic steering valve; and a second automatic steering operation valve supplying the hydraulic pressure provided from the automatic steering on-off valve to the other end of the automatic steering valve while the automatic steering on-off valve turns on the automatic driving mode to move the spool of the automatic steering valve to one end of the automatic steering valve to change the flow passage of the automatic steering valve.

Description

Hydraulic Power Steering Device {HYDRAULIC POWER STEERING APPARATUS}

The present invention relates to a hydraulic power steering device, and more particularly, to a hydraulic power steering device that is installed in a special-purpose vehicle such as a tractor, loader, forklift, wheel excavator, and packaging machine to support a manual driving mode and an automatic driving mode. it's about

In general, recently, in the case of special purpose vehicles such as tractors, loaders, forklifts, wheel excavators, packaging machines, and other transportation means, the rotational movement of the steering wheel when the driver's steering wheel is steered is controlled by hydraulic pressure so that it can be easily steered with little force when the driver steers. A steering system with a hydraulic power steering system that lightens the steering feel by converting to linear motion is used.

In the case of a special purpose vehicle, driving is often performed along a predetermined driving route. For example, in the case of a tractor, driving is performed along a predetermined zigzag-shaped path for work on arable land. Therefore, recently, research on autonomous driving technology for special-purpose vehicles such as tractors has been in-depth and has been widely applied in practice. Korean Patent Publication No. 10-2017-0108995 (September 27, 2017. Hydraulic control valve assembly of automatic steering system for agricultural machinery) and Korean Patent Publication No. 10-2013-0139475 (December 23, 2013. Autonomous steering system for tractor) A steering system for driving is disclosed.

In such an autonomous driving steering system, as in Korean Patent Laid-Open Patent No. 10-2019-0089735 (July 31, 2019. Hydraulic steering device of a working vehicle for agricultural use), an estimate of the preset driving route while changing the driving direction of the working vehicle with automatic steering When an emergency situation such as an undesirable obstacle occurs and the driver manipulates the steering wheel, the automatic steering is configured to be switched to manual steering.

However, in the conventional autonomous driving steering system as described above, when the driver attempts manual steering in an emergency, hydraulic pressure is supplied to the manual steering unit circuit prior to the automatic steering unit circuit, so that manual steering is possible, but only In a state in which only automatic steering is changed from automatic steering to manual steering, there is a risk that steering operation by the automatic steering unit may occur due to inexperienced manual steering or malfunction of the automatic steering unit. The risk due to a malfunction of the automatic steering unit is increased due to a failure or abnormality of the automatic steering unit itself.

In addition, in the conventional autonomous driving steering system, when an emergency situation such as an unexpected obstacle occurs on a preset driving path while changing the driving direction of the work vehicle by automatic steering occurs and the driver manipulates the steering wheel, automatic steering is manual Although it is configured to be switched to steering, there was also a problem in that the transition from automatic steering to manual steering was slow.

Republic of Korea Patent Publication No. 10-2017-0108995 (2017.09.27.) Republic of Korea Patent Publication No. 10-2013-0139475 (2013.12.23.) Republic of Korea Patent Publication No. 10-2019-0089735 (2019.07.31.)

SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic power steering apparatus in which a driving mode is accurately converted when a manual driving mode is switched from a manual driving mode to an automatic driving mode or when an automatic driving mode is switched to a manual driving mode.

Another object to be solved by the present invention is to provide a hydraulic power steering device capable of emergency conversion to a manual driving mode urgently from an automatic driving mode.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, a hydraulic power steering apparatus according to the present invention includes a manual steering valve, an automatic steering valve, a steering priority valve, a main switching valve, an automatic steering on-off valve, a first automatic steering operation valve, and a second automatic steering operation valve. It consists of an actuating valve. The manual steering valve supplies hydraulic pressure to any one of a left steering port and a right steering port in a manual operation mode, and receives hydraulic pressure from the other and supplies it to the tank port. In the automatic operation mode, the automatic steering valve supplies hydraulic pressure to one of the left steering port and the right steering port, and receives hydraulic pressure from the other and supplies it to the tank port. The steering priority valve receives hydraulic pressure from a pump port. In the manual operation mode, the main selector valve blocks hydraulic pressure flowing from the steering priority valve to the automatic steering valve to allow hydraulic pressure to flow from the steering priority valve to the manual steering valve. The main selector valve allows hydraulic pressure to flow from the steering priority valve to the automatic steering valve in the automatic operation mode. The automatic steering on-off valve turns on or off the automatic operation mode. The first automatic steering operation valve supplies hydraulic pressure provided from the automatic steering on-off valve to one end of the automatic steering valve when the automatic steering on-off valve turns on the automatic operation mode, The flow path of the automatic steering valve is changed by moving the spool toward the other end of the automatic steering valve. The second automatic steering operation valve supplies the hydraulic pressure provided from the automatic steering on-off valve to the other end of the automatic steering valve in a state in which the automatic steering on-off valve is turned on in the automatic operation mode. The flow path of the automatic steering valve is changed by moving the spool toward one end of the automatic steering valve.

The hydraulic power steering apparatus according to the present invention may further include a pressure reducing valve. The pressure reducing valve is configured to lower the hydraulic pressure provided from the steering priority valve to one end of the main selector valve from the manual steering valve when emergency switching to the manual operation mode among the automatic operation mode is lower than that of the main selector valve. By supplying to the other end, the main switching valve may block the hydraulic pressure flowing from the steering priority valve to the automatic steering valve.

The hydraulic power steering apparatus according to the present invention may further include an automatic steering shut-off valve. When the automatic steering on-off valve turns off the automatic operation mode, the automatic steering shut-off valve includes a hydraulic pressure flowing from the automatic steering valve to one of the left steering port and the right steering port, and hydraulic pressure flowing from the other to the automatic steering valve. can block When the automatic steering on-off valve turns on the automatic operation mode, the automatic steering shutoff valve includes a hydraulic pressure flowing from the automatic steering valve to any one of the left steering port and the right steering port, and hydraulic pressure flowing from the other to the automatic steering valve. can be opened The pressure reducing valve is configured to lower the hydraulic pressure provided from the steering priority valve to one end of the main selector valve from the manual steering valve when emergency switching to the manual operation mode among the automatic operation mode is lower than that of the automatic steering on-off valve. can be supplied with The automatic steering on-off valve may supply hydraulic pressure provided from the pressure reducing valve to the other end of the main switching valve when an emergency is switched to the manual operation mode among the automatic operation mode.

The hydraulic power steering apparatus according to the present invention may further include a load sensing valve. In the manual operation mode, the manual steering valve supplies hydraulic pressure provided from the steering priority valve to one of the left steering port and the right steering port, and receives hydraulic pressure from the other and supplies it to the tank port. In order to do this, the hydraulic pressure provided from the steering priority valve may be supplied to the manual steering valve. In the automatic operation mode, the automatic steering valve connects the hydraulic pressure provided from the main selector valve to one end of the load sensing valve to block the flow path flowing to the manual steering valve, so that the automatic steering valve It is possible to supply hydraulic pressure to the steering valve.

The hydraulic power steering apparatus according to the present invention includes a first connection flow path, a second connection flow path, a third connection flow path, a fourth connection flow path, a fifth connection flow path, a sixth connection flow path, a seventh connection flow path, an eighth connection flow path, 9 connection flow path, 10th connection flow path, 11th connection flow path, 12th connection flow path, 13th connection flow path, 14th connection flow path, 15th connection flow path, 16th connection flow path, 17th connection flow path, 18th connection flow path, No. 19 connection flow path, 20 connection flow path, 21 connection flow path, 22 connection flow path, 23 connection flow path, 24 connection flow path, 25 connection flow path, 26 connection flow path, 27 connection flow path, and 28 connection flow path are further can be configured. The first connection passage may connect the pump port and the steering priority valve. The second connection passage may connect the steering priority valve and the manual steering valve. The third connection passage may connect the manual steering valve and the left steering port. The fourth connection passage may connect the manual steering valve and the right steering port. The fifth connection passage may connect the manual steering valve and the tank port. The sixth connection passage may connect the steering priority valve and the load sensing valve. The seventh connection passage may connect the load sensing valve and the manual steering valve. The eighth connection flow path may connect the second connection flow path and the main switching valve. The ninth connection passage may connect the main switching valve and the automatic steering valve. The tenth connection passage may connect the automatic steering valve and the automatic steering shut-off valve. The eleventh connection passage may connect the automatic steering shut-off valve and the third connection passage. The twelfth connection passage may connect the automatic steering shut-off valve and the fourth connection passage. The thirteenth connection passage may connect the automatic steering shut-off valve and the automatic steering valve. The fourteenth connection passage may connect the automatic steering valve and the fifth connection passage. The fifteenth connection passage may connect the second connection passage and the pressure reducing valve. The sixteenth connection passage may connect the pressure reducing valve and the automatic steering on-off valve. The seventeenth connection passage may connect the other ends of the automatic steering on-off valve and the main switching valve. The eighteenth connection passage may connect the seventeenth connection passage and one end of the automatic steering shut-off valve. The nineteenth connection passage may connect the other end of the automatic steering shut-off valve and one end of the main switching valve, and may pass through the seventh connection passage. The twentieth connection passage may connect the load sensing valve and the automatic steering valve. The twenty-first connection passage may connect the pressure reducing valve and the fifth connection passage. The 22nd connection flow path may connect the automatic steering on-off valve and the fifth connection flow path. The 23rd connection flow path may connect the 18th connection flow path and the second automatic steering operation valve. The twenty-fourth connection passage may connect the second automatic steering operation valve and the other ends of the automatic steering valve. The twenty-fifth connection passage may connect the fifth connection passage and the second automatic steering operation valve. The 26th connection flow path may connect the 23rd connection flow path and the first automatic steering operation valve. The twenty-seventh connection passage may connect one end of the first automatic steering operation valve and the automatic steering valve. The twenty-eighth connection passage may connect the fifth connection passage and the first automatic steering operation valve.

In the manual operation mode, the steering priority valve supplies hydraulic pressure provided from the pump port through the first connection passage to the manual steering valve through the second connection passage and through the sixth connection passage. It can be supplied with a load sensing valve. In the manual operation mode, the manual steering valve supplies hydraulic pressure provided from the steering priority valve through the second connection flow path to one of the third connection flow path and the fourth connection flow path, and the hydraulic pressure provided from the other one may be supplied to the tank port through the fifth connection passage. In the manual operation mode, the main switching valve may disconnect the eighth connection passage and the ninth connection passage. In the manual operation mode, the load sensing valve supplies hydraulic pressure provided from the steering priority valve through the sixth connection passage to the manual steering valve through the seventh connection passage, so that the manual steering valve is the steering priority valve. to supply the hydraulic pressure provided through the second connection flow path to one of the third connection flow path and the fourth connection flow path from the The flow path of the steering valve can be changed.

In the automatic operation mode, the steering priority valve supplies hydraulic pressure provided from the pump port through the first connection passage to the pressure reducing valve through the second connection passage and the fifteenth connection passage, and the second It may be supplied to the main switching valve through a connection flow path and the eighth connection flow path, and may be supplied to the load sensing valve through the sixth connection flow path. In the automatic operation mode, the pressure reducing valve may supply hydraulic pressure provided from the steering priority valve through the second connection passage and the fifteenth connection passage to the automatic steering on-off valve through the sixteenth connection passage. In the automatic operation mode, the main switching valve may supply hydraulic pressure provided from the steering priority valve through the second connection passage and the eighth connection passage to the automatic steering valve through the ninth connection passage. In the automatic operation mode, the automatic steering valve supplies hydraulic pressure provided from the main selector valve through the ninth connection passage to one of the tenth connection passage and the thirteenth connection passage, and the hydraulic pressure provided from the other. may be supplied to the tank port through the fourteenth connection passage and the fifth connection passage. In the automatic operation mode, the load sensing valve disconnects the sixth connection flow path and the seventh connection flow path, so that the automatic steering valve controls the hydraulic pressure provided from the main selector valve through the ninth connection flow path to the tenth The flow path of the automatic steering valve may be changed to supply one of the connection flow path and the thirteenth connection flow path and supply hydraulic pressure provided from the other one to the tank port through the 14th connection flow path and the fifth connection flow path. . In the automatic operation mode, the automatic steering shut-off valve may connect the tenth connection flow path and the eleventh connection flow path, and also connect the twelfth connection flow path and the thirteenth connection flow path. In the automatic operation mode, the automatic steering on-off valve supplies hydraulic pressure provided from the pressure reducing valve through the 16th connection passage to the other end of the main selector valve through the 17th connection passage, so that the main selector valve The flow path of the main switching valve may be changed to supply hydraulic pressure provided from the steering priority valve through the second connection flow path and the eighth connection flow path to the automatic steering valve through the ninth connection flow path. In the automatic operation mode, the automatic steering on-off valve supplies hydraulic pressure provided from the pressure reducing valve through the 16th connection passage to one end of the automatic steering shutoff valve through the 17th connection passage and the 18th connection passage. Thus, the flow path of the automatic steering shutoff valve may be changed such that the automatic steering shutoff valve connects the tenth connection flow path and the eleventh connection flow path and connects the twelfth connection flow path and the thirteenth connection flow path. In the automatic operation mode, the automatic steering on-off valve applies hydraulic pressure provided from the pressure reducing valve through the 16th connection flow path, the 17th connection flow path, the 18th connection flow path, the 23rd connection flow path, and the 26th connection flow path. It may be supplied to the first automatic steering operation valve and the second automatic steering operation valve through a flow path. In the automatic operation mode, the first automatic steering operation valve connects the 26th connection flow path and the 27th connection flow path, disconnects the 27th connection flow path and the 28th connection flow path, and the second automatic steering An operation valve may disconnect the twenty-third connection passage and the twenty-fourth connection passage and connect the twenty-fourth connection passage and the twenty-fifth connection passage. Alternatively, in the automatic operation mode, the first automatic steering operation valve disconnects the 26th connection flow path and the 27th connection flow path, connects the 27th connection flow path and the 28th connection flow path, and the second An automatic steering operation valve may connect the 23rd connection flow path and the 24th connection flow path, and disconnect the 24th connection flow path and the 25th connection flow path.

When an emergency is switched to the manual operation mode among the automatic operation modes, the manual steering valve supplies hydraulic pressure to one end of the main switching valve and the other end of the automatic steering shut-off valve through the seventh connection passage and the 19th connection passage. Thus, the flow path of the main switching valve is changed so that the main switching valve disconnects the eighth connection flow path and the ninth connection flow path, and the automatic steering shut-off valve operates the tenth connection flow path and the eleventh connection flow path. and the flow path of the automatic steering shut-off valve may be changed to disconnect the twelfth connection flow path and the thirteenth connection flow path.

When the automatic operation mode is canceled during the automatic operation mode, the automatic steering on-off valve may include the 22 connection passage and the Supplying to the tank port through the fifth connection flow path, the main switching valve changes the flow path of the main switching valve to disconnect the eighth connection flow path and the ninth connection flow path, and the automatic steering shut-off valve may change the flow path of the automatic steering shut-off valve to disconnect the tenth connection flow path and the eleventh connection flow path and disconnect the twelfth connection flow path and the thirteenth connection flow path.

Details of other embodiments are included in the detailed description and drawings.

In a hydraulic power steering apparatus according to the present invention, the hydraulic pressure provided from the automatic steering on-off valve is supplied to one end of the automatic steering valve in a state in which the automatic steering on-off valve is turned on in an automatic operation mode, and the spool of the automatic steering valve is supplied to the spool of the automatic steering valve. A first automatic steering operation valve for changing the flow path of the automatic steering valve by moving it toward the other end of the automatic steering valve, and the automatic steering on-off valve provided from the automatic steering on-off valve in a state in which the automatic operation mode is turned on and a second automatic steering operation valve configured to change the flow path of the automatic steering valve by supplying hydraulic pressure to the other end of the automatic steering valve to move the spool of the automatic steering valve toward one end of the automatic steering valve. When the automatic operation mode is switched from the mode to the automatic operation mode or the automatic operation mode is switched from the automatic operation mode to the manual operation mode, since the automatic steering valve is operated accurately, there is an effect that the operation mode conversion is performed accurately.

In addition, the hydraulic power steering apparatus according to the present invention includes a main selector valve for supplying hydraulic pressure to the automatic steering valve in the automatic operation mode. Since a pressure reducing valve for changing the flow path of the main selector valve is provided so as not to supply hydraulic pressure to the automatic steering valve, the main selector valve switches to the automatic steering valve when an emergency switch to the manual operation mode is urgently performed during the automatic operation mode. By quickly changing the flow path of the main switching valve so as not to supply hydraulic pressure, there is an effect that an emergency conversion to the manual operation mode is possible in an emergency among the automatic operation mode.

The effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a view showing a hydraulic power steering system including a hydraulic power steering device according to an embodiment of the present invention;
2 is a circuit diagram of a hydraulic power steering system including a hydraulic power steering device according to an embodiment of the present invention;
3 is a circuit diagram showing the hydraulic flow when turning left in the manual operation mode in FIG. 2 with arrows;
4 is a circuit diagram showing the hydraulic flow with arrows when turning right in the manual operation mode in FIG. 2;
5 is a circuit diagram showing the hydraulic flow with arrows when turning left in the automatic operation mode in FIG. 2;
6 is a circuit diagram showing the hydraulic flow when turning right in the automatic operation mode in FIG. 2 with arrows;
7 is a circuit diagram showing the hydraulic pressure flow when emergency switching to a manual operation mode among automatic operation modes in FIG. 2 with arrows;
FIG. 8 is a circuit diagram showing the hydraulic pressure flow when the automatic operation mode is released during the automatic operation mode in FIG. 2 by arrows.

Hereinafter, a hydraulic power steering apparatus according to an embodiment of the present invention will be described with reference to the drawings.

1 is a view showing a hydraulic power steering system including a hydraulic power steering apparatus according to an embodiment of the present invention.

Referring to FIG. 1 , a hydraulic power steering apparatus 100 according to an embodiment of the present invention may be installed on a steering shaft 200 of a vehicle.

The upper end of the steering shaft 200 may be disposed to protrude upward of the hydraulic power steering apparatus 100 . A steering wheel 300 may be installed at an upper end of the steering shaft 200 . The steering wheel 300 may be configured to be rotated by a driver holding and rotating the vehicle in order to steer the vehicle. That is, when the driver rotates the steering wheel 300 to the left while holding the steering wheel 300 by hand in order to steer the vehicle to the left, the steering shaft 200 may be rotated to the left together with the steering wheel 300 . Also, when the driver rotates the steering wheel 300 to the right while holding the steering wheel 300 by hand to steer the vehicle to the right, the steering shaft 200 may be rotated to the right together with the steering wheel 300 .

The hydraulic power steering apparatus 100 may receive oil from the oil pump 400 . The hydraulic power steering apparatus 100 may be provided with a pump port P receiving oil from the oil pump 400 .

The oil pump 400 may pump oil stored in the oil tank 500 and supply it to the hydraulic power steering apparatus 100 . To this end, the oil pump 400 may be connected to the oil tank 500 through the first oil passage P1, and the pump port P may be connected to the oil pump 400 through the second oil passage P2. can

In addition, the hydraulic power steering apparatus 100 may recover oil to the oil tank 500 . A tank port T for recovering oil to the oil tank 500 may be formed in the hydraulic power steering apparatus 100 . The tank port T may be connected to the oil tank 500 through the third oil passage P3 .

In addition, the hydraulic power steering apparatus 100 may steer the left and right wheels 810 and 820 to the left or right. The hydraulic power steering device 100 may be provided with steering ports L and R through which oil is supplied to or recovered from the first steering cylinder device 610 and the second steering cylinder device 620 installed on the axle 700 . .

The wheels 810 and 820 may include a left wheel 810 and a right wheel 820 .

A left steering knuckle 910 may be installed inside the wheel of the left wheel 810 , and one end of the left steering knuckle 910 may be rotatably installed at the left end of the axle 700 . Also, the other end of the left steering knuckle 910 may be rotatably coupled to the left end of the link bar 930 .

A right steering knuckle 920 may be installed inside the wheel of the right wheel 820 , and one end of the right steering knuckle 920 may be rotatably installed at the right end of the axle 700 . In addition, the other end of the right steering knuckle 920 may be rotatably coupled to the right end of the link bar 930 .

Each of the first steering cylinder device 610 and the second steering cylinder device 620 may include a cylinder and a piston rod.

The end of the cylinder in the first steering cylinder device 610 may be rotatably connected to the axle 700 , and the end of the piston rod in the first steering cylinder device 610 rotates between both ends of the left steering knuckle 910 . possible to be connected.

The end of the cylinder in the second steering cylinder device 620 may be rotatably connected to the axle 700 , and the end of the piston rod in the second steering cylinder device 620 rotates between both ends of the right steering knuckle 920 . possible to be connected.

The steering ports L and R of the hydraulic power steering apparatus 100 may include a left steering port L and a right steering port R.

The left steering port L may be connected to the cylinder of the first steering cylinder device 610 and the cylinder of the second steering cylinder device 620 through the fourth oil flow path P4, and the right steering port R may be connected to the first 5 may be connected to the cylinder of the first steering cylinder device 610 and the cylinder of the second steering cylinder device 620 through the oil passage P5.

One end of the fourth oil flow path P4 may be branched into two to include a first end flow path P41 and a second end flow path P42 . Here, the first end flow path P41 may be connected to a part far from the end of the piston rod of the first steering cylinder device 610 among the cylinders of the first steering cylinder device 610 , and the second end flow path P42 is Among the cylinders of the second steering cylinder device 620 , it may be connected to a portion close to the end of the piston rod of the second steering cylinder device 620 .

One end of the fifth oil flow path P5 may be branched into two to include a third end flow path P51 and a fourth end flow path P52 . Here, the third end flow path P51 may be connected to a portion close to the end of the piston rod of the first steering cylinder device 610 among the cylinders of the first steering cylinder device 610 , and the fourth end flow path P52 is Among the cylinders of the second steering cylinder device 620 , it may be connected to a portion far from the end of the piston rod of the second steering cylinder device 620 .

Accordingly, when the oil discharged from the left steering port L moves to the cylinder of the first steering cylinder device 610 and the cylinder of the second steering cylinder device 620 through the fourth oil flow path P4, the first steering The piston rod of the cylinder device 610 rotates the left steering knuckle 910 to the left while being drawn out from the cylinder of the first steering cylinder device 610, and the piston rod of the second steering cylinder device 620 is the second steering cylinder Since the right steering knuckle 920 is rotated to the left while being inserted into the cylinder of the device 620 , the left wheel 810 and the right wheel 820 can be steered to the left. At this time, the hydraulic pressure inside the cylinder of the first steering cylinder device 610 and the hydraulic pressure inside the cylinder of the second steering cylinder device 620 move to the fifth oil passage P5 and then through the right steering port R It may be moved to the inside of the hydraulic power steering apparatus 100 , and then discharged through the tank port T and recovered to the oil tank 500 through the third oil passage P3 . That is, the hydraulic pressure moving to the cylinder of the first steering cylinder device 610 and the cylinder of the second steering cylinder device 620 through the fourth oil passage P4 flows into one side of each piston among the inside of each cylinder, The pressure may be higher than that of the other side of the piston. In addition, the hydraulic pressure flowing out from the cylinder of the first steering cylinder device 610 and the cylinder of the second steering cylinder device 620 through the fifth oil flow path P5 is filled on the other side of each piston among the inside of each cylinder. As the hydraulic pressure, the pressure may be lower than that of one side of the piston.

In addition, when the oil discharged from the right steering port R is moved to the cylinder of the first steering cylinder device 610 and the cylinder of the second steering cylinder device 620 through the fifth oil flow path P5, the first steering The piston rod of the cylinder device 610 rotates the left steering knuckle 910 to the right while being inserted into the cylinder of the first steering cylinder device 610, and the piston rod of the second steering cylinder device 620 is inserted into the second steering cylinder Since the right steering knuckle 920 is rotated to the right while being drawn out from the cylinder of the device 620 , the left wheel 810 and the right wheel 820 may be steered to the right. At this time, the hydraulic pressure inside the cylinder of the first steering cylinder device 610 and the hydraulic pressure inside the cylinder of the second steering cylinder device 620 move to the fourth oil passage P4 and then through the left steering port L It may be moved to the inside of the hydraulic power steering apparatus 100 , and then discharged through the tank port T and recovered to the oil tank 500 through the third oil passage P3 . That is, the hydraulic pressure moving to the cylinder of the first steering cylinder device 610 and the cylinder of the second steering cylinder device 620 through the fifth oil flow path P5 flows into the other side of each piston among the inside of each cylinder. The pressure may be higher than that of one side of the piston. In addition, hydraulic pressure flowing out from the cylinder of the first steering cylinder device 610 and the cylinder of the second steering cylinder device 620 through the fourth oil passage P4 is filled on one side of each piston among the inside of each cylinder. As a hydraulic pressure, the pressure may be lower than that of the other side of the piston.

2 is a circuit diagram of a hydraulic power steering system including a hydraulic power steering apparatus according to an embodiment of the present invention.

2, the hydraulic power steering apparatus 100 according to the embodiment of the present invention includes a manual steering valve 10, an automatic steering valve 20, a steering priority valve 30, a main switching valve 40, It may include an automatic steering on-off valve 60 , a first automatic steering operation valve 91 , and a second automatic steering operation valve 92 .

The manual steering valve 10 can supply hydraulic pressure to any one of the left steering port (L) and the right steering port (R) in the manual operation mode, and receive hydraulic pressure from the other and supply it to the tank port (T). have. That is, the manual steering valve 10 may supply hydraulic pressure to the left steering port (L) when turning left in the manual operation mode, and may receive hydraulic pressure from the right steering port (R) and supply it to the tank port (T). In addition, the manual steering valve 10 may supply hydraulic pressure to the right steering port (R) when turning right in the manual operation mode, and may receive hydraulic pressure from the left steering port (L) and supply it to the tank port (T). The hydraulic flow in the manual operation mode will be described later in detail with reference to FIGS. 3 and 4 .

The automatic steering valve 20 may supply hydraulic pressure to any one of the left steering port (L) and the right steering port (R) in the automatic operation mode, and may receive hydraulic pressure from the other and supply it to the tank port (T). have. That is, the automatic steering valve 20 may supply hydraulic pressure to the left steering port (L) when turning left in the automatic operation mode, and may receive hydraulic pressure from the right steering port (R) and supply it to the tank port (T). In addition, the automatic steering valve 20 may supply hydraulic pressure to the right steering port (R) when turning right in the automatic operation mode, and may receive hydraulic pressure from the left steering port (L) and supply it to the tank port (T). The hydraulic flow in the automatic operation mode will be described later in detail with reference to FIGS. 5 and 6 .

The steering priority valve 30 may receive hydraulic pressure from the pump port P.

In the manual operation mode, the main switching valve 40 blocks the hydraulic pressure flowing from the steering priority valve 30 to the automatic steering valve 20 so that the hydraulic pressure flows from the steering priority valve 30 to the manual steering valve 10. can

In addition, the main switching valve 40 may allow hydraulic pressure to flow from the steering priority valve 30 to the automatic steering valve 20 in the automatic operation mode.

The automatic steering on-off valve 60 may turn on or off the automatic operation mode.

The first automatic steering operation valve 91 applies the hydraulic pressure provided from the automatic steering on-off valve 60 to one end of the automatic steering valve 20 when the automatic steering on-off valve 60 turns on the automatic operation mode. By supplying the spool, the flow path of the automatic steering valve 20 may be changed by moving the spool of the automatic steering valve 20 toward the other end of the automatic steering valve 20 .

The second automatic steering operation valve 92 applies the hydraulic pressure provided from the automatic steering on-off valve 60 to the other end of the automatic steering valve 20 while the automatic steering on-off valve 60 turns on the automatic operation mode. By supplying it, the flow path of the automatic steering valve can be changed by moving the spool of the automatic steering valve 20 toward one end of the automatic steering valve.

The hydraulic power steering apparatus 100 according to the embodiment of the present invention may further include a pressure reducing valve 50 .

The pressure reducing valve 50 provides hydraulic pressure provided from the steering priority valve 30 to one end of the main selector valve 40 from the manual steering valve 10 when an emergency switch is made to the manual operation mode among the automatic operation mode. By supplying the lower hydraulic pressure to the other end of the main selector valve 40 , the main selector valve 40 may block the hydraulic pressure flowing from the steering priority valve 30 to the automatic steering valve 20 . The hydraulic flow during emergency conversion to the manual operation mode among the automatic operation modes will be described in detail later with reference to FIG. 7 .

The hydraulic power steering apparatus 100 according to the embodiment of the present invention may further include an automatic steering shut-off valve 70 .

The automatic steering shut-off valve 70 includes hydraulic pressure flowing from the automatic steering valve 20 to any one of the left steering port (L) and the right steering port (R) when the automatic steering on-off valve 60 turns off the automatic operation mode. It is possible to block the hydraulic pressure flowing from the other to the automatic steering valve 20 .

In addition, the automatic steering shutoff valve 70 flows from the automatic steering valve 20 to any one of the left steering port L and the right steering port R when the automatic steering on-off valve 60 turns on the automatic operation mode. It is possible to open the hydraulic pressure flowing from the other to the hydraulic pressure to the automatic steering valve 20 .

The pressure reducing valve 50 converts the hydraulic pressure provided from the steering priority valve 30 to one end of the main switching valve 40 from the manual steering valve 10 when the automatic operation mode is switched to the manual operation mode in an emergency. It can be lowered and supplied to the automatic steering on-off valve 60 .

In addition, the automatic steering on-off valve 60 may supply hydraulic pressure provided from the pressure reducing valve 50 to the other end of the main switching valve 40 when the automatic operation mode is switched to the manual operation mode in an emergency.

The hydraulic power steering apparatus 100 according to the embodiment of the present invention may further include a load sensing valve 80 .

The load sensing valve 80 supplies the hydraulic pressure provided by the manual steering valve 10 from the steering priority valve 30 to one of the left steering port (L) and the right steering port (R) in the manual operation mode, and the other The hydraulic pressure provided from the steering priority valve 30 may be supplied to the manual steering valve 10 so as to receive the hydraulic pressure from the tank port T and supply it to the tank port T.

In addition, the load sensing valve 80 connects the hydraulic pressure provided from the main switching valve 40 to the one end of the load sensing valve 80 by the automatic steering valve 20 in the automatic operation mode to the manual steering valve 10 . By blocking the flow path, hydraulic pressure may be supplied from the steering priority valve 30 to the automatic steering valve 20 .

The hydraulic pressure supplied from the steering priority valve 30 to the manual steering valve 10 is cut off so that it is supplied to the automatic steering shutoff valve 70 and supplied to the tank port T by receiving the hydraulic pressure from the automatic steering shutoff valve 70 . Thus, the flow path of the automatic steering valve 20 can be changed.

The hydraulic power steering apparatus 10 according to an embodiment of the present invention includes a first connection flow path L1, a second connection flow path L2, a third connection flow path L3, a fourth connection flow path L4, and a fifth Connection passage (L5), sixth connection passage (L6), seventh connection passage (L7), eighth connection passage (L8), ninth connection passage (L9), tenth connection passage (L10), eleventh connection passage (L11), the twelfth connection passage (L12), the thirteenth connection passage (L13), the fourteenth connection passage (L14), the fifteenth connection passage (L15), the sixteenth connection passage (L16), the seventeenth connection passage (L17) ), the 18th connection flow path (L18), the 19th connection flow path (L19), the 20th connection flow path (L20), the 21st connection flow path (L21), the 22nd connection flow path (L22), the 23rd connection flow path (L23), A twenty-fourth connection passage L24, a twenty-fifth connection passage L25, a twenty-sixth connection passage L26, a twenty-seventh connection passage L27, and a twenty-eighth connection passage L28 may be further included.

The first connection passage L1 may connect the pump port P and the steering priority valve 30 .

The second connection passage L2 may connect the steering priority valve 30 and the manual steering valve 10 .

The third connection passage L3 may connect the manual steering valve 10 and the left steering port L.

The fourth connection passage L4 may connect the manual steering valve 10 and the right steering port R.

The fifth connection passage L5 may connect the manual steering valve 10 and the tank port T.

The sixth connection flow path L6 may connect the steering priority valve 30 and the load sensing valve 80 .

The seventh connection passage L7 may connect the load sensing valve 80 and the manual steering valve 10 .

The eighth connection flow path L8 may connect the second connection flow path L2 and the main switching valve 40 .

The ninth connection passage L9 may connect the main switching valve 40 and the automatic steering valve 20 .

The tenth connection passage L10 may connect the automatic steering valve 20 and the automatic steering shut-off valve 70 .

The eleventh connection flow path L11 may connect the automatic steering shut-off valve 70 and the third connection flow path L3.

The twelfth connection flow path L12 may connect the automatic steering shut-off valve 70 and the fourth connection flow path L4.

The thirteenth connection passage L13 may connect the automatic steering shutoff valve 70 and the automatic steering valve 20 to each other.

The fourteenth connection flow path L14 may connect the automatic steering valve 20 and the fifth connection flow path L5.

The fifteenth connection passage L15 may connect the second connection passage L2 and the pressure reducing valve 50 .

The sixteenth connection passage L16 may connect the pressure reducing valve 50 and the automatic steering on-off valve 60 .

The seventeenth connection passage L17 may connect the other ends of the automatic steering on-off valve 60 and the main switching valve 40 .

The eighteenth connection passage L18 may connect one end of the seventeenth connection passage L17 and the automatic steering shut-off valve 70 .

The 19th connection flow path L19 may connect the other end of the automatic steering shut-off valve 70 and one end of the main switching valve 40 . The nineteenth connection passage L19 may pass through the seventh connection passage L7.

The twentieth connection passage L20 may connect the load sensing valve 80 and the automatic steering valve 20 .

The twenty-first connection passage L21 may connect the pressure reducing valve 50 and the fifth connection passage L5.

The 22nd connection flow path L22 may connect the automatic steering on-off valve 60 and the 5th connection flow path L5.

The twenty-third connection passage L23 may connect the eighteenth connection passage L18 and the second automatic steering operation valve 92 to each other.

The twenty-fourth connection passage L24 may connect the other ends of the second automatic steering operation valve 92 and the automatic steering valve 20 .

The twenty-fifth connection passage L25 may connect the fifth connection passage L5 and the second automatic steering operation valve 92 to each other.

The 26th connection flow path L26 may connect the 23rd connection flow path L23 and the first automatic steering operation valve 91 .

The twenty-seventh connection passage L27 may connect one end of the first automatic steering operation valve 91 and the automatic steering valve 20 .

The twenty-eighth connection passage L28 may connect the fifth connection passage L5 and the first automatic steering operation valve 91 to each other.

A first check valve CV1 may be installed in the second connection passage L2 between a portion to which the fifteenth connection passage L15 is connected and the manual steering valve 10 . The first check valve CV1 may prevent a reverse flow of hydraulic pressure supplied from the steering priority valve 30 to the manual steering valve 10 through the second connection passage L2 .

In the third connection passage L3 , a second check valve CV2 may be installed between a portion to which the eleventh connection passage L11 is connected and the manual steering valve 10 . The second check valve CV2 may prevent a reverse flow of hydraulic pressure supplied from the manual steering valve 10 to the left steering port L through the third connection passage L3 .

A third check valve CV3 may be installed in the fourth connection passage L3 between a portion to which the twelfth connection passage L12 is connected and the manual steering valve 10 . The third check valve CV3 may prevent a reverse flow of hydraulic pressure supplied from the manual steering valve 10 to the right steering port R through the fourth connection passage L4.

The hydraulic power steering apparatus 100 according to the embodiment of the present invention may further include a gerotor pump (G). The manual steering valve 10 may supply hydraulic pressure provided from the steering priority valve 30 through the second connection passage L2 to the gerotor pump G. The gerotor pump G may increase the hydraulic pressure provided from the manual steering valve 10 and then supply it back to the manual steering valve 10 . The manual steering valve 10 may supply hydraulic pressure provided from the gerotor pump G to the third connection flow path L3 or the fourth connection flow path L4 . When turning left in the manual operation mode, the manual steering valve 10 may supply hydraulic pressure provided from the gerotor pump G to the third connection passage L3. When turning right in the manual operation mode, the manual steering valve 10 may supply hydraulic pressure provided from the gerotor pump G to the fourth connection flow path L4.

The hydraulic power steering apparatus 100 according to the embodiment of the present invention may further include a 29th connection passage L29. The 29th connection flow path L29 may connect the steering priority valve 30 and the external device EF. When the manual steering valve 10 and the automatic steering valve 20 are not operated, the steering priority valve 30 may supply hydraulic pressure to the external device EF through the 29th connection passage L29.

3 is a circuit diagram showing the hydraulic flow when turning left in the manual operation mode in FIG. 2 with arrows, and FIG. 4 is a circuit diagram showing the hydraulic flow when turning right in the manual operation mode in FIG. 2 by arrows.

Referring to FIGS. 3 and 4 , in the manual operation mode, the steering priority valve 30 applies hydraulic pressure provided from the pump port P through the first connection flow path L1 and the second connection flow path L2. In addition to supplying to the manual steering valve 10 through the through, it can be supplied to the load sensing valve 80 through the sixth connection flow path (L6).

In addition, in the manual operation mode, the manual steering valve 10 applies the hydraulic pressure provided from the steering priority valve 30 through the second connection passage L2 to the third connection passage L3 and the fourth connection passage L4. In addition to supplying to any one of the hydraulic pressure provided from the other one may be supplied to the tank port (T) through the fifth connection flow path (L5).

In addition, in the manual operation mode, the main switching valve 40 may disconnect the eighth connection flow path L8 and the ninth connection flow path L9.

In addition, in the manual operation mode, the load sensing valve 80 transfers the hydraulic pressure provided from the steering priority valve 30 through the sixth connection passage L6 to the manual steering valve 10 through the seventh connection passage L7. By supplying, the manual steering valve 10 supplies the hydraulic pressure provided from the steering priority valve 30 through the second connection flow path L2 to any one of the third connection flow path L3 and the fourth connection flow path L4. The flow path of the manual steering valve 10 may be changed to supply the hydraulic pressure provided from the other one to the tank port T through the fifth connection flow path L5.

That is, referring to FIG. 3 , when turning left in the manual operation mode, the steering priority valve 30 applies the hydraulic pressure provided from the pump port P through the first connection passage L1 to the second connection passage L2. It may be supplied to the manual steering valve 10 through the , and may be supplied to the load sensing valve 80 through the sixth connection flow path L6.

In addition, when turning left in the manual operation mode, the manual steering valve 10 supplies the hydraulic pressure provided from the steering priority valve 30 through the second connection flow path L2 to the third connection flow path L3 and the fourth Hydraulic pressure provided from the connection flow path L4 may be supplied to the tank port T through the fifth connection flow path L5 .

In addition, when turning left in the manual operation mode, the main switching valve 40 may disconnect the eighth connection flow path L8 and the ninth connection flow path L9.

In addition, when turning left in the manual operation mode, the load sensing valve 80 applies the hydraulic pressure provided from the steering priority valve 30 through the sixth connection passage L6 to the manual steering valve 10 through the seventh connection passage L7. ), the manual steering valve 10 supplies the hydraulic pressure provided from the steering priority valve 30 through the second connection flow path L2 to the third connection flow path L3 and from the fourth connection flow path L4. The flow path of the manual steering valve 10 may be changed to supply the provided hydraulic pressure to the tank port T through the fifth connection flow path L5.

In addition, referring to FIG. 4 , when turning right in the manual operation mode, the steering priority valve 30 applies the hydraulic pressure provided from the pump port P through the first connection passage L1 to the second connection passage L2. It may be supplied to the manual steering valve 10 through the , and may be supplied to the load sensing valve 80 through the sixth connection flow path L6.

In addition, when turning right in the manual operation mode, the manual steering valve 10 supplies the hydraulic pressure provided from the steering priority valve 30 through the second connection flow path L2 to the fourth connection flow path L4 and the third Hydraulic pressure provided from the connection flow path L3 may be supplied to the tank port T through the fifth connection flow path L5 .

In addition, when turning right in the manual operation mode, the main switching valve 40 may disconnect the eighth connection flow path L8 and the ninth connection flow path L9.

In addition, when turning right in the manual operation mode, the load sensing valve 80 transfers the hydraulic pressure provided from the steering priority valve 30 through the sixth connection passage L6 to the manual steering valve 10 through the seventh connection passage L7. ), the manual steering valve 10 supplies the hydraulic pressure provided from the steering priority valve 30 through the second connection flow path L2 to the fourth connection flow path L4 and from the third connection flow path L3. The flow path of the manual steering valve 10 may be changed to supply the provided hydraulic pressure to the tank port T through the fifth connection flow path L5.

5 is a circuit diagram showing the hydraulic flow when turning left in the automatic operation mode in FIG. 2 with arrows, and FIG. 6 is a circuit diagram showing the hydraulic pressure flow when turning right in the automatic operation mode in FIG. 2 by arrows.

5 and 6, in the automatic operation mode, the steering priority valve 30, the hydraulic pressure provided from the pump port (P) through the first connection passage (L1), the second connection passage (L2) and It is supplied to the pressure reducing valve 50 through the fifteenth connection passage (L15) and supplied to the main switching valve 40 through the second connection passage (L2) and the eighth connection passage (L8), while being supplied to the sixth connection passage ( It can be supplied to the load sensing valve 80 through L6).

In addition, in the automatic operation mode, the pressure reducing valve 50 transmits the hydraulic pressure provided from the steering priority valve 30 through the second connection flow path L2 and the 15th connection flow path L15 through the 16th connection flow path L16. It can be supplied to the automatic steering on-off valve (60).

In addition, in the automatic operation mode, the main switching valve 40 transfers the hydraulic pressure provided from the steering priority valve 30 through the second connection passage L2 and the eighth connection passage L8 to the ninth connection passage L9. It can be supplied to the automatic steering valve 20 through the.

In addition, in the automatic operation mode, the automatic steering valve 20 applies the hydraulic pressure provided from the main switching valve 40 through the ninth connection passage L9 to the tenth connection passage L10 and the thirteenth connection passage L13. In addition to supplying to any one of the hydraulic pressure provided from the other one may be supplied to the tank port (T) through the 14th connection flow path (L14) and the fifth connection flow path (L5).

In addition, in the automatic operation mode, the load sensing valve 80 disconnects the sixth connection passage L6 and the seventh connection passage L7, so that the automatic steering valve 20 is released from the main selector valve 40 . The hydraulic pressure provided through the 9 connection flow path L9 is supplied to any one of the tenth connection flow path L10 and the thirteenth connection flow path L13, and the hydraulic pressure provided from the other is supplied to the 14th connection flow path L14 and the fifth connection flow path L14. The flow path of the automatic steering valve 20 may be changed so that it is supplied to the tank port T through the flow path L5.

In addition, in the automatic operation mode, the automatic steering shutoff valve 70 connects the tenth connection flow path L10 and the eleventh connection flow path L11, as well as the twelfth connection flow path L12 and the thirteenth connection flow path L13. ) can be connected.

In addition, in the automatic operation mode, the automatic steering on-off valve 60 applies the hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection passage L16, and the main selector valve 40 through the 17th connection passage L17. ), the main selector valve 40 supplies the hydraulic pressure provided from the steering priority valve 30 through the second connection flow path L2 and the eighth connection flow path L8 through the ninth connection flow path L9. The flow path of the main switching valve 40 may be changed to supply to the automatic steering valve 20 .

In addition, in the automatic operation mode, the automatic steering on-off valve 60 applies the hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection flow path L16, the 17th connection flow path L17 and the 18th connection flow path L18. ) to one end of the automatic steering shutoff valve 70, and the automatic steering shutoff valve 70 connects the tenth connection flow path L10 and the 11th connection flow path L11, and the twelfth connection flow path L12 and The flow path of the automatic steering shut-off valve 70 may be changed to connect the thirteenth connection flow path L13.

In addition, in the automatic operation mode, the automatic steering on-off valve 60 controls the hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection flow path L16, the 17th connection flow path L17 and the 18th connection flow path L18. ), the 23 th connection passage L23 and the 26 th connection passage L26 may be supplied to the first automatic steering operation valve 91 and the second automatic steering operation valve 92 .

In addition, in the automatic operation mode, the first automatic steering operation valve 91 connects the 26th connection flow path L26 and the 27th connection flow path L27, and the 27th connection flow path L27 and the 28th connection flow path L28 ), and the second automatic steering operation valve 92 disconnects the 23rd connection flow path (L23) and the 24th connection flow path (L24), and the 24th connection flow path (L24) and the 25th connection flow path ( L25) can be connected. Alternatively, in the automatic operation mode, the first automatic steering operation valve 91 disconnects the 26th connection flow path L26 and the 27th connection flow path L27, and the 27th connection flow path L27 and the 28th connection flow path ( L28), the second automatic steering operation valve 92 connects the 23rd connection flow path L23 and the 24th connection flow path L24, and the 24th connection flow path L24 and the 25th connection flow path L25 ) can be disconnected.

That is, referring to FIG. 5 , when turning left in the automatic operation mode, the steering priority valve 30 applies the hydraulic pressure provided from the pump port P through the first connection passage L1 to the second connection passage L2. And while supplying to the pressure reducing valve 50 through the fifteenth connection passage (L15), while supplying to the main switching valve 40 through the second connection passage (L2) and the eighth connection passage (L8), as well as the sixth connection passage It can be supplied to the load sensing valve 80 through (L6).

In addition, when turning left in the automatic operation mode, the pressure reducing valve 50 applies the hydraulic pressure provided from the steering priority valve 30 through the second connection flow path L2 and the 15th connection flow path L15 to the 16th connection flow path L16. It can be supplied to the automatic steering on-off valve 60 through the.

In addition, when turning left in the automatic operation mode, the main switching valve 40 transfers the hydraulic pressure provided from the steering priority valve 30 through the second connection passage L2 and the eighth connection passage L8 to the ninth connection passage L9. ) through the automatic steering valve 20 can be supplied.

In addition, when turning left in the automatic operation mode, the automatic steering valve 20 supplies the hydraulic pressure provided from the main selector valve 40 through the ninth connection passage L9 to the tenth connection passage L10 and the thirteenth Hydraulic pressure provided from the connection flow path L13 may be supplied to the tank port T through the fourteenth connection flow path L14 and the fifth connection flow path L5 .

In addition, when turning left in the automatic operation mode, the load sensing valve 80 disconnects the sixth connection passage L6 and the seventh connection passage L7, so that the automatic steering valve 20 becomes the main switching valve 40 The hydraulic pressure supplied from the ninth connection passage L9 is supplied to the tenth connection passage L10 and the hydraulic pressure provided from the thirteenth connection passage L13 is supplied to the 14th connection passage L14 and the fifth connection passage L5. ), it is possible to change the flow path of the automatic steering valve 20 to supply to the tank port (T).

In addition, when turning left in the automatic operation mode, the automatic steering shutoff valve 70 connects the tenth connection flow path L10 and the eleventh connection flow path L11 as well as the twelfth connection flow path L12 and the thirteenth connection flow path. (L13) can be connected.

In addition, when turning left in the automatic operation mode, the automatic steering on-off valve 60 applies hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection passage L16, and through the 17th connection passage L17, the main switching valve Supplying to the other end of (40), the main switching valve (40) from the steering priority valve (30) through the second connection flow path (L2) and the eighth connection flow path (L8) through the ninth connection flow path (L9) It is possible to change the flow path of the main switching valve 40 to supply to the automatic steering valve 20 through the .

In addition, when turning left in the automatic operation mode, the automatic steering on-off valve 60 applies the hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection flow path L16, the 17th connection flow path L17 and the 18th connection flow path. Supply to one end of the automatic steering shut-off valve 70 through (L18), the automatic steering shut-off valve 70 connects the tenth connection passage L10 and the eleventh connection passage L11, and the twelfth connection passage L12 ) and the thirteenth connection flow path (L13) may be changed to the flow path of the automatic steering shut-off valve (70).

In addition, when turning left in the automatic operation mode, the automatic steering on-off valve 60 uses the hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection flow path L16, the 17th connection flow path L17 and the 18th connection flow path. It may be supplied to the first automatic steering operation valve 91 and the second automatic steering operation valve 92 through (L18), the 23rd connection flow path L23, and the 26th connection flow path L26.

In addition, when turning left in the automatic operation mode, the first automatic steering operation valve 91 connects the 26th connection flow path L26 and the 27th connection flow path L27, and the 27th connection flow path L27 and the 28th connection flow path. In addition to disconnecting (L28), the second automatic steering operation valve 92 disconnects the 23rd connection flow path (L23) and the 24th connection flow path (L24), and the 24th connection flow path (L24) and the 25th connection A flow path (L25) can be connected.

Also, referring to FIG. 6 , when turning right in the automatic operation mode, the steering priority valve 30 applies the hydraulic pressure provided from the pump port P through the first connection passage L1 to the second connection passage L2. And while supplying to the pressure reducing valve 50 through the fifteenth connection passage (L15), while supplying to the main switching valve 40 through the second connection passage (L2) and the eighth connection passage (L8), as well as the sixth connection passage It can be supplied to the load sensing valve 80 through (L6).

In addition, when turning right in the automatic operation mode, the pressure reducing valve 50 applies the hydraulic pressure provided from the steering priority valve 30 through the second connection flow path L2 and the 15th connection flow path L15 to the 16th connection flow path L16. It can be supplied to the automatic steering on-off valve 60 through the.

In addition, when turning right in the automatic operation mode, the main switching valve 40 transfers the hydraulic pressure provided from the steering priority valve 30 through the second connection passage L2 and the eighth connection passage L8 to the ninth connection passage L9. ) through the automatic steering valve 20 can be supplied.

In addition, when turning right in the automatic operation mode, the automatic steering valve 20 supplies the hydraulic pressure provided from the main switching valve 40 through the ninth connection passage L9 to the thirteenth connection passage L13 as well as the tenth Hydraulic pressure provided from the connection flow path L10 may be supplied to the tank port T through the fourteenth connection flow path L14 and the fifth connection flow path L5 .

In addition, when turning right in the automatic operation mode, the load sensing valve 80 disconnects the sixth connection passage L6 and the seventh connection passage L7, so that the automatic steering valve 20 operates the main switching valve 40 The hydraulic pressure supplied from the ninth connection passage L9 is supplied to the thirteenth connection passage L13 and the hydraulic pressure provided from the tenth connection passage L10 is supplied to the 14th connection passage L14 and the fifth connection passage L5. ), it is possible to change the flow path of the automatic steering valve 20 to supply to the tank port (T).

In addition, when turning right in the automatic operation mode, the automatic steering shutoff valve 70 connects the tenth connection passage L10 and the eleventh connection passage L11, as well as the twelfth connection passage L12 and the thirteenth connection passage. (L13) can be connected.

In addition, when turning right in the automatic operation mode, the automatic steering on-off valve 60 applies the hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection flow path L16, and through the 17th connection flow path L17, the main switching valve Supplying to the other end of (40), the main switching valve (40) from the steering priority valve (30) through the second connection flow path (L2) and the eighth connection flow path (L8) through the ninth connection flow path (L9) It is possible to change the flow path of the main switching valve 40 to supply to the automatic steering valve 20 through the .

In addition, when turning right in the automatic operation mode, the automatic steering on-off valve 60 applies the hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection flow path L16, the 17th connection flow path L17 and the 18th connection flow path. Supply to one end of the automatic steering shut-off valve 70 through (L18), the automatic steering shut-off valve 70 connects the tenth connection passage L10 and the eleventh connection passage L11, and the twelfth connection passage L12 ) and the thirteenth connection flow path (L13) may be changed to the flow path of the automatic steering shut-off valve (70).

In addition, when turning right in the automatic operation mode, the automatic steering on-off valve 60 applies the hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection flow path L16, the 17th connection flow path L17 and the 18th connection flow path. It may be supplied to the first automatic steering operation valve 91 and the second automatic steering operation valve 92 through (L18), the 23rd connection flow path L23, and the 26th connection flow path L26.

In addition, when turning right in the automatic operation mode, the first automatic steering operation valve 91 disconnects the 26th connection passage L26 and the 27th connection passage L27 and connects the 27th connection passage L27 and the 28th connection passage. In addition to connecting the flow path L28, the second automatic steering operation valve 92 connects the 23rd connection flow path L23 and the 24th connection flow path L24, and the 24th connection flow path L24 and the 25th connection flow path. (L25) can be disconnected.

FIG. 7 is a circuit diagram showing the hydraulic pressure flow when emergency switching to a manual operation mode among automatic operation modes in FIG. 2 is indicated by arrows. Here, only the emergency left turn conversion to the manual operation mode while turning left in the automatic operation mode will be described as an example.

Referring to FIG. 7 , when an emergency is switched to the manual operation mode among the automatic operation mode, the manual steering valve 10 is connected to the main switching valve 40 through the seventh connection passage L7 and the 19th connection passage L19. By supplying hydraulic pressure to one end of the and the other end of the automatic steering shut-off valve 70, the main selector valve 40 disconnects the eighth connection passage L8 and the ninth connection passage L9. In addition to changing the flow path of The flow path of the automatic steering shut-off valve 70 may be changed to disconnect.

That is, when an emergency is switched to the manual operation mode among the automatic operation mode, the manual steering valve 10 is connected to one end of the main switching valve 40 through the seventh connection passage L7 and the 19th connection passage L19 and automatically When hydraulic pressure is supplied to the other end of the steering shutoff valve 70, the main selector valve 40 has a higher hydraulic pressure at one end connected to the 19th connection passage L19 than the hydraulic pressure at the other end connected to the 17th connection passage L17. , as the spool of the main switching valve 40 is moved to the left in the drawing to change the flow path, the main switching valve 40 may disconnect the eighth connection flow path L8 and the ninth connection flow path L9. Here, in the main switching valve 40, the reason that the hydraulic pressure of one end connected to the 19th connection passage L19 is higher than the hydraulic pressure of the other end connected to the 17th connection passage L17 is that the pressure reducing valve 50 is connected to the 17th connection passage ( This is because the hydraulic pressure supplied to L17) was reduced.

In addition, when emergency switching to the manual operation mode among the automatic operation mode, the manual steering valve 10 is connected to one end of the main selector valve 40 and the automatic When hydraulic pressure is supplied to the other end of the steering shut-off valve 70, the automatic steering shut-off valve 70 sets the hydraulic pressure at one end to which the 18th connection flow path L18 is connected is lower than the hydraulic pressure at the other end to which the 19th connection flow path L19 is connected. Therefore, as the spool of the automatic steering shutoff valve 70 is moved to the left in the drawing and the flow path is changed, the automatic steering shutoff valve 70 disconnects the tenth connection flow path L10 and the eleventh connection flow path L11 and The twelfth connection flow path L12 and the thirteenth connection flow path L13 may be disconnected. Here, in the automatic steering shutoff valve 70 , the reason that the hydraulic pressure at one end to which the 18th connection flow path L18 is connected is lower than the hydraulic pressure at the other end to which the 19th connection flow path L19 is connected is the reason why the pressure reducing valve 50 is connected to the 18th connection flow path. This is because the hydraulic pressure supplied to (L18) is reduced.

FIG. 8 is a circuit diagram showing the hydraulic pressure flow when the automatic operation mode is released during the automatic operation mode in FIG. 2 by arrows. Here, only when the automatic operation mode is canceled while turning left in the automatic operation mode will be described as an example.

Referring to FIG. 8 , when the automatic operation mode is released during the automatic operation mode, the automatic steering on-off valve 60 connects the hydraulic pressure provided from the pressure reducing valve 50 through the sixteenth connection passage L16 to a seventeenth connection. It is not supplied to the flow path L17, but is supplied to the tank port T through the 22nd connection flow path L22 and the 5th connection flow path L5, so that the main selector valve 40 is connected to the 8th connection flow path L8 and the second connection flow path L8. 9 The flow path of the main selector valve 40 is changed to disconnect the connection flow path L9, and the automatic steering shutoff valve 70 disconnects the 10 connection flow path L10 and the 11th connection flow path L11, and The flow path of the automatic steering shutoff valve 70 may be changed to disconnect the twelfth connection flow path L12 and the thirteenth connection flow path L13 .

That is, when the automatic operation mode is released during the automatic operation mode, the automatic steering on-off valve 60 transfers the hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection passage L16 to the 17th connection passage L17. When supply is supplied to the tank port T through the 22nd connection flow path L22 and the 5th connection flow path L5 without supplying, the main switching valve 40 releases the hydraulic pressure on the 17th connection flow path L17 side and , by the spring force on the side of the 19th connection flow path (L19), the spool of the main switching valve 40 is moved to the left in the drawing to change the flow path. The ninth connection flow path L9 may be disconnected.

In addition, when the automatic operation mode is canceled during the automatic operation mode, the automatic steering on-off valve 60 transfers the hydraulic pressure provided from the pressure reducing valve 50 through the 16th connection passage L16 to the 17th connection passage L17. When supply is supplied to the tank port T through the 22nd connection flow path L22 and the fifth connection flow path L5 without supplying, the automatic steering shutoff valve 70 is the hydraulic pressure of one end connected to the 18th connection flow path L18. is released, and the spool of the automatic steering shutoff valve 70 is moved to the left in the drawing by the spring force on the side of the 19th connection flow path L19 to change the flow path, and the automatic steering cutoff valve 70 is connected to the 10th connection The flow path L10 and the eleventh connection flow path L11 may be disconnected, and the twelfth connection flow path L12 and the thirteenth connection flow path L13 may be disconnected.

As described above, the hydraulic power steering apparatus 100 according to the embodiment of the present invention automatically controls the hydraulic pressure provided from the automatic steering on-off valve 60 in a state in which the automatic steering on-off valve 60 turns on the automatic operation mode. The first automatic steering operation valve 91 for changing the flow path of the automatic steering valve 20 by supplying it to one end of the steering valve 20 and moving the spool of the automatic steering valve 20 toward the other end of the automatic steering valve 20 . ), and the automatic steering on-off valve 60 supplies the hydraulic pressure provided from the automatic steering on-off valve 60 to the other end of the automatic steering valve 20 in a state in which the automatic operation mode is turned on to the automatic steering valve 20 Since it includes a second automatic steering operation valve 92 that changes the flow path of the automatic steering valve 20 by moving the spool of the automatic steering valve 20 toward one end of the automatic steering valve 20, when switching from the manual operation mode to the automatic operation mode Alternatively, when the automatic operation mode is switched from the automatic operation mode to the manual operation mode, the operation of the automatic steering valve 20 is accurately performed, so that the operation mode conversion is accurately performed.

In addition, the hydraulic power steering apparatus 100 according to the embodiment of the present invention includes a main selector valve 40 for supplying hydraulic pressure to the automatic steering valve 20 in the automatic operation mode. Since the pressure reducing valve 50 for changing the flow path of the main selector valve 40 is provided so that the hydraulic pressure at the other end is lowered than the hydraulic pressure at the other end so that the main selector valve 40 does not supply the hydraulic pressure to the automatic steering valve 20, the automatic During the automatic operation mode, the flow path of the main selector valve 40 is quickly changed so that the main selector valve 40 does not supply hydraulic pressure to the automatic steering valve 20 when an emergency switch to the manual operation mode is urgently performed during the operation mode. Emergency conversion to manual operation mode becomes possible in an emergency.

Those of ordinary skill in the art to which the present invention pertains will understand that the present invention may be embodied in other specific forms without changing the technical spirit or essential features thereof. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention.

10: manual steering valve 20: automatic steering valve
30: steering priority valve 40: main selector valve
50: pressure reducing valve 60: automatic steering on-off valve
70: automatic steering shut-off valve 80: load sensing valve
91: first automatic steering operation valve 92: second automatic steering operation valve
100: hydraulic power steering device L: left steering port
L1: first connection passage L2: second connection passage
L3: third connection passage L4: fourth connection passage
L5: fifth connection passage L6: sixth connection passage
L7: seventh connection passage L8: eighth connection passage
L9: ninth connection passage L10: tenth connection passage
L11: 11th connection flow path L12: 12th connection flow path
L13: 13th connection flow path L14: 14th connection flow path
L15: fifteenth connection passage L16: sixteenth connection passage
L17: 17th connection flow path L18: 18th connection flow path
L19: 19th connection flow path L20: 20th connection flow path
L21: 21st connection flow path L22: 22nd connection flow path
L23: 23rd connection flow path L24: 24th connection flow path
L25: 25th connection flow path L26: 26th connection flow path
L27: 27th connection flow path L28: 28th connection flow path
P : Pump port R : Right steer port
T: tank port

Claims (9)

In the manual operation mode, a manual steering valve for supplying hydraulic pressure to one of the left steering port and the right steering port, and receiving hydraulic pressure from the other and supplying the hydraulic pressure to the tank port;
an automatic steering valve supplying hydraulic pressure to one of the left steering port and the right steering port in the automatic operation mode, receiving hydraulic pressure from the other, and supplying the hydraulic pressure to the tank port;
Steering priority valve receiving hydraulic pressure from the pump port;
In the manual operation mode, the hydraulic pressure flowing from the steering priority valve to the automatic steering valve is blocked so that the hydraulic pressure flows from the steering priority valve to the manual steering valve, and in the automatic operation mode, from the steering priority valve to the automatic steering valve a main selector valve that allows hydraulic pressure to flow;
an automatic steering on-off valve for turning on or off the automatic operation mode;
When the automatic steering on-off valve turns on the automatic operation mode, the hydraulic pressure provided from the automatic steering on-off valve is supplied to one end of the automatic steering valve, and the spool of the automatic steering valve is connected to the other end of the automatic steering valve. a first automatic steering operation valve for changing a flow path of the automatic steering valve by moving it toward; and
When the automatic steering on-off valve turns on the automatic operation mode, the hydraulic pressure provided from the automatic steering on-off valve is supplied to the other end of the automatic steering valve, and the spool of the automatic steering valve is connected to one end of the automatic steering valve. A hydraulic power steering device including a; a second automatic steering operation valve for changing the flow path of the automatic steering valve by moving toward the The method according to claim 1,
When emergency switching to the manual operation mode in the automatic operation mode, the hydraulic pressure provided from the steering priority valve is lower than the hydraulic pressure provided from the manual steering valve to one end of the main selector valve and supplied to the other end of the main selector valve. and a pressure reducing valve allowing the main switching valve to block the hydraulic pressure flowing from the steering priority valve to the automatic steering valve. 3. The method according to claim 2,
When the automatic steering on-off valve turns off the automatic operation mode, the hydraulic pressure flowing from the automatic steering valve to any one of the left steering port and the right steering port and the hydraulic pressure flowing from the other one to the automatic steering valve are cut off, an automatic steering shutoff valve that opens hydraulic pressure flowing from the automatic steering valve to any one of the left steering port and the right steering port and hydraulic pressure flowing from the other to the automatic steering valve when the steering on-off valve turns on the automatic operation mode; further comprising,
When the automatic operation mode is switched to the manual operation mode in an emergency, the pressure reducing valve lowers the hydraulic pressure provided from the steering priority valve than the hydraulic pressure provided from the manual steering valve to one end of the main selector valve to lower the automatic steering on-off valve and the automatic steering on-off valve supplies the hydraulic pressure provided from the pressure reducing valve to the other end of the main switching valve. 4. The method according to claim 3,
In the manual operation mode, the manual steering valve supplies the hydraulic pressure provided from the steering priority valve to one of the left steering port and the right steering port, and receives the hydraulic pressure from the other to supply the hydraulic pressure to the tank port. It further includes; a load sensing valve for supplying the hydraulic pressure provided from the manual steering valve to the
In the automatic operation mode, the automatic steering valve connects the hydraulic pressure provided from the main selector valve to one end of the load sensing valve to block the flow path flowing to the manual steering valve, so that the automatic steering valve A hydraulic power steering system that supplies hydraulic pressure to the steering valve. 5. The method according to claim 4,
a first connection passage connecting the pump port and the steering priority valve;
a second connection passage connecting the steering priority valve and the manual steering valve;
a third connection passage connecting the manual steering valve and the left steering port;
a fourth connection passage connecting the manual steering valve and the right steering port;
a fifth connection passage connecting the manual steering valve and the tank port;
a sixth connection passage connecting the steering priority valve and the load sensing valve;
a seventh connection passage connecting the load sensing valve and the manual steering valve;
an eighth connection passage connecting the second connection passage and the main switching valve;
a ninth connection passage connecting the main switching valve and the automatic steering valve;
a tenth connection passage connecting the automatic steering valve and the automatic steering shut-off valve;
an eleventh connection passage connecting the automatic steering shut-off valve and the third connection passage;
a twelfth connection passage connecting the automatic steering shut-off valve and the fourth connection passage;
a thirteenth connection passage connecting the automatic steering shut-off valve and the automatic steering valve;
a 14th connection flow path connecting the automatic steering valve and the fifth connection flow path;
a fifteenth connection passage connecting the second connection passage and the pressure reducing valve;
a 16th connection passage connecting the pressure reducing valve and the automatic steering on-off valve;
a 17th connection passage connecting the other ends of the automatic steering on-off valve and the main switching valve;
an 18th connection flow path connecting the 17th connection flow path and one end of the automatic steering shut-off valve;
a 19th connection passage connecting the other end of the automatic steering shut-off valve and one end of the main switching valve and passing through the seventh connection passage;
a twentieth connection passage connecting the load sensing valve and the automatic steering valve;
a 21st connection passage connecting the pressure reducing valve and the fifth connection passage;
a 22nd connection passage connecting the automatic steering on-off valve and the fifth connection passage;
a 23rd connection flow path connecting the 18th connection flow path and the second automatic steering operation valve;
a twenty-fourth connection passage connecting the second automatic steering operation valve and the other end of the automatic steering valve;
a 25th connection flow path connecting the fifth connection flow path and the second automatic steering operation valve;
a 26th connection flow path connecting the 23rd connection flow path and the first automatic steering operation valve;
a 27th connection passage connecting the first automatic steering operation valve and one end of the automatic steering valve;
The hydraulic power steering apparatus further comprising a twenty-eighth connection passage connecting the fifth connection passage and the first automatic steering operation valve. 6. The method of claim 5,
In the manual operation mode,
The steering priority valve supplies hydraulic pressure provided from the pump port through the first connection flow path to the manual steering valve through the second connection flow path and supplies the load sensing valve through the sixth connection flow path, and ,
The manual steering valve supplies hydraulic pressure provided from the steering priority valve through the second connection flow path to one of the third connection flow path and the fourth connection flow path, and supplies hydraulic pressure provided from the other to the fifth connection flow path. is supplied to the tank port through
The main switching valve disconnects the eighth connection flow path and the ninth connection flow path,
The load sensing valve supplies hydraulic pressure provided from the steering priority valve through the sixth connection passage to the manual steering valve through the seventh connection passage, so that the manual steering valve moves from the steering priority valve to the second connection passage. Change the flow path of the manual steering valve so that the hydraulic pressure provided through hydraulic power steering system. 7. The method of claim 6,
In the automatic operation mode,
The steering priority valve supplies hydraulic pressure provided through the first connection passage from the pump port to the pressure reducing valve through the second connection passage and the fifteenth connection passage, and the second connection passage and the eighth connection passage. It is supplied to the main switching valve through a connection flow path and is supplied to the load sensing valve through the sixth connection flow path,
the pressure reducing valve supplies hydraulic pressure provided from the steering priority valve through the second connection passage and the fifteenth connection passage to the automatic steering on-off valve through the sixteenth connection passage,
the main switching valve supplies hydraulic pressure provided from the steering priority valve through the second connection passage and the eighth connection passage to the automatic steering valve through the ninth connection passage,
The automatic steering valve supplies hydraulic pressure provided from the main switching valve through the ninth connection flow path to one of the tenth connection flow path and the thirteenth connection flow path, and supplies hydraulic pressure provided from the other to the 14th connection flow path. and supplying to the tank port through the fifth connection passage,
The load sensing valve disconnects the sixth connection passage and the seventh connection passage, so that the automatic steering valve applies hydraulic pressure provided from the main switching valve through the ninth connection passage to the tenth connection passage and the thirteenth connection passage. Changing the flow path of the automatic steering valve to supply one of the connection flow paths and supply hydraulic pressure provided from the other to the tank port through the 14th connection flow path and the fifth connection flow path,
The automatic steering shut-off valve connects the tenth connection flow path and the eleventh connection flow path, and also connects the twelfth connection flow path and the thirteenth connection flow path,
The automatic steering on-off valve supplies hydraulic pressure provided from the pressure reducing valve through the 16th connection flow path to the other end of the main selector valve through the 17th connection flow path so that the main selector valve moves from the steering priority valve to the first The flow path of the main switching valve is changed to supply hydraulic pressure provided through the second connection flow path and the eighth connection flow path to the automatic steering valve through the ninth connection flow path, and the 17th connection flow path and the 18th connection flow path are changed. The automatic steering shut-off valve connects the tenth connection flow path and the eleventh connection flow path and connects the twelfth connection flow path and the thirteenth connection flow path by supplying it to one end of the automatic steering shutoff valve through a flow path. The first automatic steering operation valve and the second automatic steering operation valve through the 17th connection flow path, the 18th connection flow path, the 23rd connection flow path, and the 26th connection flow path while changing the flow path of the shut-off valve supplied with
The first automatic steering operation valve connects the 26th connection passage and the 27th connection passage and disconnects the 27th connection passage and the 28th connection passage, and the second automatic steering operation valve connects the 23rd connection passage. Disconnecting the connection flow path and the 24th connection flow path and connecting the 24 connection flow path and the 25th connection flow path, or the first automatic steering operation valve disconnects the 26th connection flow path and the 27th connection flow path, The 27th connection flow path and the 28th connection flow path are connected, and the second automatic steering operation valve connects the 23rd connection flow path and the 24th connection flow path, and connects the 24th connection flow path and the 25th connection flow path. Hydraulic power steering to disconnect. 8. The method of claim 7,
In case of emergency conversion to the manual operation mode among the automatic operation modes,
The manual steering valve supplies hydraulic pressure to one end of the main switching valve and the other end of the automatic steering shut-off valve through the seventh connection flow path and the 19th connection flow path, so that the main switching valve is connected to the eighth connection flow path and the The flow path of the main switching valve is changed to disconnect the ninth connection flow path, and the automatic steering shut-off valve disconnects the tenth connection flow path and the eleventh connection flow path, and the twelfth connection flow path and the thirteenth connection flow path A hydraulic power steering device for changing the flow path of the automatic steering shut-off valve to disconnect the flow path. 8. The method of claim 7,
When the automatic operation mode is canceled during the automatic operation mode,
The automatic steering on-off valve supplies the hydraulic pressure provided from the pressure reducing valve through the 16th connection flow path to the 17th connection flow path, but supplies it to the tank port through the 22nd connection flow path and the fifth connection flow path. Thus, the flow path of the main switching valve is changed so that the main switching valve disconnects the eighth connection flow path and the ninth connection flow path, and the automatic steering shut-off valve operates the tenth connection flow path and the eleventh connection flow path. A hydraulic power steering apparatus for changing the flow path of the automatic steering shut-off valve to disconnect the connection and disconnect the twelfth connection flow path and the thirteenth connection flow path.

Images