JP2008037192A - Power steering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power steering device capable of automatically performing steering control when a driver is determined to be dozing even when a hydraulic actuator is used.
SOLUTION: Environmental information detection means for detecting vehicle, driver or road information, hydraulic pressure control section for controlling hydraulic pressure supplied to an input shaft drive section based on an output signal of the environmental information detection means, and output A shaft, which is formed at a position spaced apart from the input shaft drive portion in the axial direction, and is formed in a housing and a first oil passage connected to the control valve, and connects the first oil passage and the first pressure chamber. A second oil passage and an output shaft, the input shaft driving portion being formed at a position spaced apart from each other in the axial direction, a third oil passage connected to the control valve, a housing, and a third oil passage And a fourth oil passage connecting the second pressure chamber.
[Selection] Figure 2

Description

  The present invention relates to a power steering device that assists a driver's steering force with hydraulic pressure, and more particularly to an integral type power steering device used for a large vehicle.

Conventionally, in accordance with the vehicle driving support device disclosed in Patent Document 1, a white line recognition camera is used to appropriately drive a vehicle without deviating from the driving lane when the driver is falling asleep or driving aside. And a camera for recognizing the line of sight and blinking, and safety is ensured by automatically performing steering control when the vehicle deviates from the white line or the driver is determined to be dozing.
JP 11-339199 A

  However, in the above prior art, since automatic steering control is performed by an electric signal, automatic steering control can be easily applied to a type of power steering device using an electric motor as an actuator. In this case, since it is difficult to assist the steering with the electric motor, a hydraulic power steering apparatus that does not use the electric motor as an actuator is generally used. For this reason, it has been difficult to apply the above-described automatic steering control such as a dozing prevention function to the hydraulic actuator of the hydraulic power steering apparatus.

  The present invention has been made paying attention to the above problems, and the purpose thereof is to perform steering control automatically when the driver is determined to be dozing even when a hydraulic actuator is used. An object of the present invention is to provide a power steering device that can perform the above-described operation.

  To achieve the above object, according to the present invention, a housing, an input shaft connected to a steering wheel, an output shaft accommodated in the housing and connected to the input shaft via a torsion bar, and accommodated in the housing A piston that divides the interior of the housing into a first pressure chamber and a second pressure chamber, a conversion mechanism that converts rotation of the input shaft into axial movement of the piston, the first pressure chamber, and the second pressure chamber. An oil pump that supplies hydraulic pressure to the pressure chamber and a hydraulic oil that is formed between the input shaft and the output shaft and that is supplied from the oil pump is selected based on the relative rotation between the input shaft and the output shaft. And a control valve for supplying the first pressure chamber and the second pressure chamber, a transmission mechanism for transmitting the axial movement of the piston to the steering wheel, and the output shaft. An input shaft drive unit that applies torque to the input shaft by hydraulic pressure from an oil pump, environmental information detection means that detects vehicle, driver, or road information, and the input based on an output signal of the environmental information detection means A hydraulic pressure control unit for controlling a hydraulic pressure supplied to the shaft driving unit, and the output shaft, the input shaft driving unit being formed at a position spaced apart in the axial direction and connected to the control valve; A first oil passage, a second oil passage formed in the housing and connecting the first oil passage and the first pressure chamber, and the output shaft, the axial separation from the input shaft drive unit A third oil passage formed at the position and connected to the control valve, and a fourth oil passage formed in the housing and connecting the third oil passage and the second pressure chamber. .

  Therefore, even when a hydraulic actuator is used, it is possible to provide a power steering device that can automatically perform steering control when the driver is determined to be dozing.

  Hereinafter, the best mode for realizing the power steering apparatus of the present invention will be described based on an embodiment shown in the drawings.

[System configuration of power steering system]
Example 1 will be described with reference to FIGS. FIG. 1 is a system configuration diagram of the power steering apparatus 1 of the present application.

  The power steering device 1 is provided in an input shaft 2 connected to a steering wheel SW, a control valve 600 that switches an assist direction, a hydraulic power cylinder 10 that generates assist force by hydraulic pressure, and meshes with the piston 70. And a sector shaft 30 (transmission mechanism) that rotates by the reciprocating motion of the piston 70 to steer the steered wheels.

  The input shaft 2 includes an input shaft 40 and an output shaft 60, and a torsion bar 50 (see FIG. 2) connecting the input / output shafts 40 and 60. Further, the power steering apparatus 1 supplies the left and right rotation input shaft driving units 100 and 200 (input shaft driving units) that apply a reaction force to the input shaft 40 by hydraulic pressure, and the input shaft driving units 100 and 200. And a hydraulic pressure control unit 300 that controls the hydraulic pressure of the hydraulic oil.

  The left and right rotation input shaft driving units 100 and 200 are actuators that apply left and right torques to the input shaft 40, respectively. It functions as a reaction force actuator during normal steering, and when automatic steering control is required, such as during a driver's drowsy driving or side-viewing driving, the input valve 40 is rotated to drive the control valve 600 to steer in the direction of torque application. It functions as a steering actuator that performs assist.

  When the steering wheel SW is steered, the hydraulic oil discharged from the pump P is supplied to one of the first and second pressure chambers 21 and 22 separated by the control valve 600. As a result, the piston 70 is driven, and the sector shaft 30 is rotated and steered. Excess hydraulic fluid is discharged to the reservoir 5.

  The hydraulic pressure control unit 300 includes a control unit 301 and left and right rotation control valves 310 and 320. The control unit 301 is connected to the battery E and drives the left and right rotation control valves 310 and 320 based on a signal from the environment information detection unit 400 (environment information detection means) that detects the vehicle environment. The control valves 310 and 320 are connected to the control valve 600 through oil passages 6 and 7, respectively, and are supplied with the discharge pressure of the pump P.

  The environment information detection unit 400 includes a vehicle speed sensor 401, a white line recognition camera 403 on the road, and a driver's line-of-sight recognition camera 402. The control unit 301 drives the control valves 310 and 320 for left rotation and right rotation based on the detected vehicle speed, the positional relationship between the white line and the vehicle, and the driver's line of sight.

  As a result, the left and right rotation input shaft drive units 100 and 200 are driven during a drowsy operation or a side-view operation, and a reaction torque in the left-right direction is applied to the input shaft 40. A warning is issued to the driver by vibrating the steering wheel SW connected to the input shaft 40.

  The left rotation and right rotation control valves 310 and 320 are connected to the control valve 600 to receive hydraulic oil. When the input shaft 40 rotates relative to the output shaft 60 in the right direction, hydraulic oil is supplied to the left rotation control valve 310, and when it rotates relative to the left direction, it is supplied to the right rotation control valve 320. Excess hydraulic fluid is discharged to the reservoir 5.

  The left and right rotation control valves 310 and 320 include left and right rotation direction torque generation solenoids SOL1 and SOL2, and left and right rotation direction torque generation spools 311 and 321, respectively. The spools 311 and 321 are driven by driving the solenoids SOL1 and SOL2 based on a command from the control unit 301, and the hydraulic pressure supplied to the left and right rotation input shaft driving units 100 and 200 is controlled. .

  The left and right rotating input shaft driving units 100 and 200 are provided on the input shaft 40 and apply a reaction force to the input shaft 40 by the hydraulic pressure from the control valves 310 and 320. The left rotation input shaft drive unit 100 applies a left rotation direction torque to the input shaft 40, and the right rotation input shaft drive unit 200 applies a right rotation direction torque.

[Axial sectional view]
FIG. 2 is an axial sectional view of the power steering apparatus. For the sake of explanation, the axial direction of the input / output shafts 40 and 60 is defined as the y-axis, and the input shaft 40 side is positive. Also, polar coordinates are defined around the y axis, and the radial direction is the r axis (the rotation direction is counterclockwise positive, see FIG. 3).

  The power steering apparatus 1 includes a first housing 11 that houses a control valve 600 and a second housing 12 that houses a piston 70. The sector shaft 30 is provided in the sector shaft storage portion 13 in the second housing.

  The housings 11 and 12 are both substantially cup-shaped members and are connected to each other in the axial direction opening. An input shaft 40 connected to the steering wheel is inserted into the bottom of the first housing 11 in the axial direction, and the piston 70 in the second housing 12 is slid in the y-axis direction by hydraulic pressure according to the rotation of the input shaft 40. .

  The second housing 12 and the sector shaft 30 are provided at right angles to each other in the axial direction. The teeth provided on the piston 70 in the second housing 12 and the teeth provided on the sector shaft 30 mesh with each other, and the piston slides. The sector shaft 30 is rotated to perform steering assist.

  A piston 70 is accommodated in the second housing 12 so as to be movable in the axial direction, and the piston 70 causes the second housing 12 to have a first pressure chamber 21 on the input shaft side (volume increase during steering in the right direction) and a cup-shaped bottom portion. The second pressure chamber 22 on the side (the volume is increased during leftward steering) is kept liquid-tight.

  The input shaft 40 is connected to the output shaft 60 by a torsion bar 50. The output shaft 60 has a hollow cylindrical shape, and the input shaft 40 is accommodated on the y axis positive direction side of the hollow portion, and the torsion bar 50 is accommodated on the y axis negative direction side. By providing the torsion bar 50 between the input / output shafts 40, 60, the torque applied to the input shaft 40 from the input shaft driving units 100, 200 is absorbed by the elastic force of the torsion bar 50, and the influence on the steered wheels is affected. Make it smaller.

  The solenoids SOL1 and SOL2 and the spools 311 and 321 are provided on the same axis in the y-axis direction and parallel to the input shaft 40. This suppresses an increase in the size of the apparatus in the radial direction (r-axis direction).

  Each of the input shaft driving units 100 and 200 has rod-shaped protrusions 110 and 210 and pistons 120 and 220, which are on the y-axis negative direction side of the control valve 600, and the output shafts 40 and 60 overlap. Is provided. The left rotation input shaft drive unit 100 and the right rotation input shaft drive unit 200 are provided in this order from the y-axis negative direction side.

  The projecting portions 110 and 220 are embedded in the input shaft 40 and rotate integrally, and the outer diameter end portions 111 and 211 project to the outer diameter side of the input shaft 40. The pistons 120 and 220 are embedded in the output shaft 60 so as to be slidable in the r-axis direction (movable in the radial direction) with respect to 101 and 201 provided at equal intervals in the circumferential direction.

  On the inner diameter side of the pistons 120 and 220, concave portions 121 and 221 that are recessed in a mortar shape toward the outer diameter direction are provided. . Moreover, the front-end | tip of the protrusion part outer diameter direction edge part 111,211 is provided in the curved surface shape.

  At the time of assembly, outer diameter direction end portions 111 and 211 of the projecting portions 110 and 120 are inserted into the concave portions 121 and 221 and brought into contact with each other. Thereby, each drive part 100,200 is latched by each piston 120,220 with the permissible amount of rotation for the radial direction width of crevice 121,221, and avoids twisting torsion bar 50 more than necessary.

  A left rotation direction torque generation chamber D1 (first hydraulic pressure introduction portion) is formed on the r axis direction outer diameter side of the left rotation piston 120, and the outer diameter portion of the piston 120 receives the hydraulic pressure of D1. It becomes. Similarly, a right rotation direction torque generation chamber D2 (second hydraulic pressure introduction portion) and a pressure receiving portion 222 are formed on the outer diameter side of the right rotation piston 220.

  The left rotation direction torque generation chamber D1 is connected to the left rotation control valve 310 via the first oil passage 510 and the oil passage 33, and the right rotation direction torque generation chamber D2 is connected to the third oil passage 530 and the oil passage 34. Connected to the control valve 320 for right rotation.

  The y-axis direction positions of the first and third oil passages 510 and 530 are provided at positions different from the y-axis direction positions of the input shaft driving units 100 and 200, respectively. The positions of the input shaft driving units 100 and 200 and the first and third oil passages 510 and 530 are sufficiently separated from each other, and a sufficient installation space for the input shaft driving units 100 and 200 is ensured.

  The left rotation direction torque generation chamber D1 communicates with the first pressure chamber 21 by the oil passage 31, the left rotation control valve 310, and the oil passage 33, and the right rotation direction torque generation chamber D2 has the oil passage 32, right rotation. The control valve 320 and the oil passage 34 communicate with the second pressure chamber 22.

  The first oil passage 510 communicates with the first pressure chamber 21 via the second oil passage 520 provided in the first housing 11, and the third oil passage 530 is provided in the first housing 11. The second pressure chamber 22 communicates with the four oil passages 540. Accordingly, the hydraulic pressures in the first and second pressure chambers 21 and 22 are controlled by the control valves 310 and 320 and supplied to the left and right rotation input shaft driving units 100 and 200.

  The output shaft 60 is inserted into the piston 70 in the axial direction, and is fitted to the piston 70 by the ball screw mechanism 61. A piston tooth portion 71 (conversion mechanism) carved in the circumferential direction is provided on the outer periphery of the piston 70, and the piston 70 meshes with the sector shaft 30 in the piston tooth portion 71.

  The second housing 12 is provided so that its axis is orthogonal to the sector shaft 30, and a sector shaft storage portion 13 that stores a part of the sector shaft 30 is provided in a part of the second housing 12 in the radial direction. The sector shaft storage portion 13 is supplied with hydraulic oil and communicates with the first pressure chamber 21 to lubricate the sector shaft 30 and the piston tooth portion 71 in mesh.

  The first pressure chamber 21 in the second housing 12 communicates with the control valve 600 through the right steering cylinder chamber communication passage 15 provided in the first housing 11, and the second pressure chamber 22 includes the second housing 12 and the first housing. 11 communicates with the control valve 600 by a left steering cylinder chamber communication passage 16 provided across the control valve 600.

  The control valve 600 functions as a valve mechanism that introduces or discharges oil from the IN port and the OUT port to the first and second pressure chambers 21 and 22 according to the rotation of the input shaft 40. When the input shaft 40 rotates to the right relative to the output shaft 60, the pump P and the first pressure chamber 21 are communicated. When relatively rotated to the left, the pump P communicates with the second pressure chamber 22.

[Details of input shaft drive]
FIG. 3 is a radial cross-sectional view of the input shaft drive unit 200 for right rotation. The left rotation input shaft driving unit 100 provided on the y-axis positive direction side is indicated by a broken line.

  As described above, the left and right rotation input shaft driving units 100 and 200 are rotated in the left and right rotation directions respectively in the four radial holes 101 and 201 in the r-axis direction provided at equal intervals with respect to the output shaft 60. It is formed by retracting the torque generating pistons 120 and 220. Left-rotation direction and right-rotation direction torque generation chambers D1 and D2 are formed on the outer diameter side of the pistons 120 and 220 in the r-axis direction.

  The pressure receiving portions 122 and 222 receive the hydraulic pressures of the torque generating chambers D1 and D2, and the pistons 120 and 220 move to the inner diameter side in the r-axis direction. Therefore, the outer diameter direction ends 111 and 211 of the protrusions 110 and 210 abut against the recesses 121 and 221 of the pistons 120 and 220, and the pistons 120 and 220 press the protrusions 110 and 210.

  Here, the input shaft driving units 100 and 200 for left and right rotation are provided with their rotational directions shifted from each other. That is, the AA line which is the axis of the radial hole 101 in the left rotation input shaft drive unit 100 (the line passing through the deepest part of the recess 121) and the axis of the radial hole 211 of the right rotation input shaft drive unit. Certain BB lines are offset from each other by an angle θ.

  Due to this offset, the AA lines of the radial holes 101 and 201 are provided with a shift of θ / 2 counterclockwise with respect to the CC line that is the axis of the protrusions 110 and 210. Similarly, the BB line is provided with an angle θ / 2 shifted clockwise from the CC line.

  Therefore, the piston 120 for left rotation presses the protrusion part 110 in the recessed part 121a of the CC line side rather than the AA line, and presses the protrusion parts 110 and 210 in the left rotation direction. The piston 220 for right rotation presses the protrusion 110 in the recess 221a on the CC line side with respect to the line BB, and presses the protrusions 110 and 210 in the right rotation direction. Thereby, the hydraulic pressure in the left rotation direction and right rotation direction torque generation chambers D1 and D2 is efficiently converted into torque.

[Supplying hydraulic oil to the input shaft drive]
FIG. 4 is a cross-sectional view in the axial direction of the power steering apparatus 1 at the time of rightward steering assist. When the steering wheel SW is steered rightward, the control valve 600 introduces pump pressure into the first pressure chamber 21 (volume expansion during rightward steering), and a differential pressure is generated between the first and second pressure chambers 21 and 22. appear. As a result, the piston 70 moves in the negative y-axis direction, the sector shaft 30 rotates counterclockwise, and rightward steering assist is performed.

  At this time, the hydraulic oil in the first pressure chamber 21 is introduced into the left rotation control valve 310 through the oil passage 31 and hydraulically controlled, and is introduced into the left rotation direction torque generation chamber D1 through the oil passage 33. As a result, the left rotation piston 120 is driven, and the left rotation input shaft drive unit 100 presses the input shaft 40 in the left rotation direction to apply reaction torque.

  Similarly, during left-hand steering assist, the hydraulic oil in the second pressure chamber 22 is also introduced into the right-rotation direction torque generation chamber D2 via the oil passage 16 and the oil passages 32 and 34, and the right-rotation input shaft drive unit receives input. The shaft 40 is pressed in the clockwise direction to apply a reaction force torque.

  Since the recesses 121 and 221 that are contact surfaces between the pistons 120 and 220 and the protrusions 110 and 210 are inclined with respect to the advancing / retreating direction (r-axis direction) of the pistons 120 and 220, the recesses 121, By adjusting the tilt angle of 221, the torque generated by the input shaft drive unit is adjusted.

  Moreover, since the front-end | tip parts 111 and 211 of the protrusion parts 110 and 210 are formed in the curved surface shape, the advancing / retreating motion of piston 120,220 is converted into the rotational motion of the input shaft 40 smoothly.

[Applying reaction force to the input shaft]
FIG. 5 is a radial cross-sectional view of the left rotation input shaft drive unit 100, and FIG. A case where torque is applied to each input shaft 40 is shown. An enlarged view of the vicinity of the piston 120 of the left rotation input shaft driving unit 100 is shown in FIG.

(Normal steering)
As described above, when the hydraulic pressure in the first pressure chamber 21 is high during normal steering, the input shaft 40 is given a torque in the left rotation direction by the left rotation input shaft drive unit 100, and the second pressure chamber 22 When the hydraulic pressure is high, torque in the clockwise direction is applied. According to the vehicle speed detected by the vehicle speed sensor 401, the left and right rotation control valves 310 and 320 are driven, and torque corresponding to the environmental information is applied to the input shaft 40.

(When snoozing is detected)
When the driver's drowsiness is detected by the line-of-sight recognition camera 402, the left and right rotation control valves 310 and 320 are alternately driven, and the torque generation chambers of the left and right rotation input shaft driving units 100 and 200 are driven. The hydraulic pressures of D1 and D2 are alternately raised and lowered.

  Accordingly, the left and right rotational direction torque generating pistons 120 and 220 alternately press the input shaft 40, and the input shaft 40 repeats left-right bi-directional rotation and vibrates in the torsional direction. As a result, the steering wheel SW connected to the input shaft 40 vibrates in the left-right twist direction, and issues a warning to the driver.

(When lane departure is detected)
When the lane departure state is detected by the white line recognition camera 403, the left and right rotation control valves 310 and 320 are driven to rotate the input shaft 40 and enter within the allowable rotation range of the serration grooves 41 and 61. The output shafts 40 and 60 are relatively rotated. As a result, the opening degree of the control valve 600 is changed, steering assist is performed, and the lane is returned.

  For example, when the vehicle deviates to the left, the control valve 320 for right rotation is driven to apply a reaction force in the right rotation direction to the input shaft 40, and the control valve 600 is rotated to the right side. As a result, the hydraulic pressure in the right steering cylinder chamber 21 increases, and an assist force in the right steering direction is generated to turn the vehicle in the right direction to avoid lane departure. When the vehicle is deviating to the left side, the vehicle is turned counterclockwise by driving the control valve 310 for left rotation.

[Effect of the embodiment of the present application]
(1) Housing 10, input shaft 40 connected to steering wheel, output shaft 60 accommodated in housing 10 and connected to input shaft 40 via torsion bar 50, and housing 10 accommodated in this housing 10, a piston 70 that divides the inside of the first pressure chamber 21 and the second pressure chamber 22, a conversion mechanism that converts the rotation of the input shaft 40 into an axial movement of the piston 70, the first pressure chamber 21 and the second pressure An oil pump P that supplies hydraulic pressure to the chamber 22 and an operation that is formed between the input shaft 40 and the output shaft 60 and that is supplied from the oil pump P based on the relative rotation between the input shaft 40 and the output shaft 60. A control valve 600 that selectively supplies oil to the first pressure chamber 21 and the second pressure chamber 22, a transmission mechanism that transmits the axial movement of the piston 70 to the steered wheels, and an output shaft 6 Input shaft drive units 100 and 200 that apply torque to the input shaft 40 by hydraulic pressure from the oil pump P, environmental information detection means that detects vehicle, driver, or road information, and environmental information detection means Are hydraulic pressure control units 310 and 320 for controlling the hydraulic pressure supplied to the input shaft driving units 100 and 200 based on the output signal of the output shaft 60, and the output shaft 60. A first oil passage 510 formed at a position different in the axial direction and connected to the control valve 600 and a second oil passage 520 formed in the housing 10 and connecting the first oil passage 510 and the first pressure chamber 21. A third oil passage 530 formed at a position where the axial position of the output shaft 60 is different from that of the input shaft driving units 100 and 200 and connected to the control valve 600; Formed in Managing 10, it was to have a fourth oil passage 540 that connects the third oil passage 530 and the second pressure chamber 22.

  As a result, the positions of the input shaft driving units 100 and 200 and the first and third oil passages 510 and 530 can be sufficiently separated from each other, and a sufficient installation space for the input shaft driving units 100 and 200 is ensured. Without providing a drive source such as an electric motor, a torque can be applied to the input shaft 40 to add a drowsiness prevention function, an automatic steering function, or the like.

[Other embodiments]
The best mode for carrying out the present invention has been described based on the embodiments. However, the specific configuration of the present invention is not limited to each embodiment, and the scope of the invention is not deviated. Design changes and the like are included in the present invention.

  For example, as shown in FIG. 8, a spherical protrusion 123 may be provided at the tip of the piston 120, a serration groove 41 may be provided on the outer periphery of the input shaft 40, and the groove 41 may be pressed by the protrusion 123.

  Further, technical ideas other than the claims that can be grasped from the above embodiments will be described below together with the effects thereof.

(A) In the power steering apparatus according to claim 1,
The environmental information detection means detects a driver's doze or side-view driving.

  When the driver's dozing or side-by-side driving is detected, the input shaft driving unit applies torque to the input shaft, so that the driver can warn the driver of falling asleep due to the generation of this torque.

(B) In the power steering device according to claim 1,
The environmental information detection means detects a relative position between the traveling road and the vehicle,
The hydraulic pressure control unit drives and controls the input shaft driving unit based on an output signal of the environment information detecting unit so that the vehicle does not deviate from the traveling road.

  Drive control of the input shaft drive unit so that the vehicle does not deviate from the travel path, and drive control of the hydraulic power cylinder by the hydraulic pressure from the pump, without specially providing an actuator to drive and control the steering wheel and steered wheels, Lane departure prevention control can be performed.

(C) In the power steering device according to claim 1,
The input shaft drive unit includes a protrusion formed on the outer peripheral side of the input shaft,
It is provided in the output shaft so as to be able to advance and retract in the radial direction, and has a contact portion that contacts the protruding portion on one side of the forward and backward direction, and a pressure receiving portion that receives the hydraulic pressure from the hydraulic pressure control portion on the other side of the forward and backward direction A power steering apparatus comprising: a piston.

  The hydraulic pressure from the pump can be efficiently converted into torque that is applied to the input shaft.

(D) In the power steering device described in (c) above,
The power steering device according to claim 1, wherein the contact surface of the piston is an inclined surface inclined with respect to the advancing / retreating direction of the piston.

  By adjusting the angle of the inclined surface, the torque generated by the input shaft driving unit can be adjusted.

(E) In the power steering apparatus described in (d) above,
The power steering device according to claim 1, wherein a tip of the protruding portion is formed in a curved shape.

  Piston movement can be smoothly converted into rotational movement of the input shaft.

(G) In the power steering device described in (f) above,
The power steering apparatus according to claim 1, wherein the first input shaft drive unit and the second input shaft drive unit are provided apart in the axial direction.

  Each space of the first and second input shaft driving units can be sufficiently secured.

(H) In the power steering device described in (f) above,
The environmental information detection means detects a driver's doze or side-view driving,
The hydraulic pressure control unit alternately supplies hydraulic pressure to the first input shaft drive unit and the second input shaft drive unit when the environmental information detection unit detects a driver's dozing or side-view driving. A featured power steering device.

  By driving the input shaft to rotate alternately in the forward and reverse directions, it is possible to give a warning to the driver about a drowsy driving or a side driving.

(L) In the power steering device described in (F) above,
The environmental information detection means detects a relative position between the traveling road and the vehicle,
The fluid pressure control unit selectively supplies fluid pressure to the first input shaft drive unit or the second input shaft drive unit based on a relative position between the traveling path and the vehicle detected by the environment information detection unit. A power steering device characterized by:

  By driving the input shaft to rotate in a direction in which the vehicle does not deviate from the travel path, it is possible to prevent the vehicle from departing from the travel path.

(Nu) In the power steering device according to claim 1,
The hydraulic pressure control unit includes a solenoid that is driven and controlled based on an output signal from the environmental information detection means, and a spool valve that is connected to the solenoid and controls the hydraulic pressure from the oil pump to the input shaft driving unit. A power steering device.

  The hydraulic pressure can be controlled based on the output signal from the environmental information detection means.

(Le) In the power steering apparatus described in (nu) above,
The power steering device, wherein the solenoid and the spool valve are coaxial and are provided in parallel with the input shaft.

  An increase in the radial dimension of the apparatus can be suppressed.

1 is a system configuration diagram of a power steering apparatus 1 of the present application. It is an axial sectional view of a power steering device. It is radial direction sectional drawing of a 1st input shaft drive part. It is an axial sectional view of a power steering device at the time of right direction steering assist. It is radial direction sectional drawing of the input shaft drive part for left rotation. It is radial direction sectional drawing of the input shaft drive part for right rotation. It is an expanded sectional view of the input shaft drive part for left rotation. It is a figure which shows another Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Power steering apparatus 2 Input shaft 5 Reservoir 10 Hydraulic power cylinders 11 and 12 1st, 2nd housing 13 Sector shaft storage part 15 Right steering cylinder chamber communication path 16 Left steering cylinder chamber communication path 21, 22 1st, 1st 2 Pressure chamber 30 Sector shaft 40 Input shaft 50 Torsion bar 60 Output shaft 70 Pistons 100, 200 Left and right rotation input shaft drive units 110, 210 Protruding portions 111, 211 Outer diameter direction ends 120, 220 Pistons 121, 221 Recesses 300 Hydraulic pressure control unit 301 Control units 310, 320 Left and right rotational direction torque generation control valves 311, 321 Spool 400 Environmental information detection unit 401 Vehicle speed sensor 402 Line-of-sight recognition camera 403 White line recognition camera 510-540 First to fourth oil passages 600 Control valve D , D2 left, right rotation direction torque generating chamber E battery P pump SOL1, SOL2 solenoid

Claims (1)

A housing;
An input shaft connected to the steering wheel;
An output shaft housed in the housing and connected to the input shaft via a torsion bar;
A piston housed in the housing and separating the interior of the housing into a first pressure chamber and a second pressure chamber;
A conversion mechanism that converts rotation of the input shaft into axial movement of the piston;
An oil pump for supplying hydraulic pressure to the first pressure chamber and the second pressure chamber;
The hydraulic oil that is formed between the input shaft and the output shaft and that is supplied from the oil pump based on the relative rotation between the input shaft and the output shaft is selectively used for the first pressure chamber and the second pressure. A control valve for supplying to the chamber,
A transmission mechanism for transmitting the axial movement of the piston to the steering wheel;
An input shaft driving unit that is provided on the output shaft and applies torque to the input shaft by a hydraulic pressure from the oil pump;
Environmental information detection means for detecting vehicle, driver or road information;
A hydraulic pressure control unit that controls the hydraulic pressure supplied to the input shaft driving unit based on an output signal of the environmental information detection means;
A first oil passage which is the output shaft, is formed at a position where the axial direction position of the output shaft is different from the input shaft drive unit, and is connected to the control valve;
A second oil passage formed in the housing and connecting the first oil passage and the first pressure chamber;
A third oil passage which is the output shaft, is formed at a position where the axial direction position of the output shaft is different from the input shaft drive unit, and is connected to the control valve;
A power steering device, comprising: a fourth oil passage formed in the housing and connecting the third oil passage and the second pressure chamber.

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