JPH1016801A - Steering control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simply structured and low-cost vehicular steering control device for constituting, by hydraulic control, for instance an automatic steering mode or a steering force variable mechanism. SOLUTION: In a vehicular steering control device 60, the valve body 14 and the valve shaft 16 of a control valve 10 are engaged with each other so as to be associatively displaced around an axis and along an axial direction. The recessed groove 24 of the valve body 14 and the land part 32 of the valve shaft 16 are formed to be spiral along the axis. Thus, by not only associatively rotating the valve body 14 and the valve shaft 16 but also associatively displacing these along the axial direction, an automatic steering mode or a steering force variable mechanism is provided by hydraulic control, and without needing any other special hydraulic control systems, a structure is simplified and costs are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a steering control device for a vehicle such as an automobile.

[0002]

2. Description of the Related Art In a steering control device for a vehicle such as an automobile (for example, a hydraulic power steering device), for example, a manual steering mode in which a driver operates a steering wheel and a running state of the vehicle are detected. There is a power steering device capable of selectively switching between an automatic steering mode for automatically performing steering (for example, see Japanese Patent Application Laid-Open No.
-95575).

[0003] The power steering apparatus disclosed in this publication includes a hydraulic actuator for steering a steered wheel, and a hydraulic steering system for steering by distributing and controlling the hydraulic pressure from a hydraulic pump by operating a steering wheel. In the mode, the steering wheel is steered by supplying hydraulic pressure from the automatic steering hydraulic system.

However, this power steering apparatus is provided with an automatic steering hydraulic system used in an automatic steering mode, in addition to a hydraulic steering system used in a normal operation (manual steering mode in which steering is performed by steering). Therefore, the configuration of the hydraulic circuit and the like is complicated as a whole, and there is a problem in terms of arrangement space and cost.

[0005]

SUMMARY OF THE INVENTION In consideration of the above facts, the present invention provides a vehicle steering system capable of realizing a simple structure and an inexpensive structure for forming, for example, an automatic steering mode or a variable steering force mechanism by hydraulic control. The aim is to obtain a control device.

[0006]

According to a first aspect of the present invention, there is provided a vehicle steering control device having a valve shaft having spiral valve grooves opposed to each other and capable of being relatively displaced around an axis and along an axial direction. And a hydraulic control valve that controls supply and discharge of hydraulic pressure by a relative displacement between the valve shaft and the valve body.

In the vehicle steering control device according to the first aspect, not only can the supply and discharge of the hydraulic pressure be controlled by relative displacement of the valve shaft and the valve body of the hydraulic control valve around the axis, but also along the axial direction. The relative displacement can also control the supply and discharge of the hydraulic pressure.

Therefore, different hydraulic steering systems (for example, a manual steering hydraulic system used in the manual steering mode and an automatic steering hydraulic system used in the automatic steering mode) are constituted only by using the single hydraulic control valve. And the structure is simple and inexpensive.

According to a second aspect of the present invention, in the vehicle steering control apparatus according to the first aspect, the hydraulic control valve is disposed in a steering mechanism connecting the steering wheel and the steered wheels. And an actuating means for displacing the valve shaft and the valve body relative to the axis around the axis by steering wheel operation, and displacing the valve shaft and the valve body of the hydraulic control valve relatively along the axial direction. And

In the vehicle steering control device according to the second aspect, the valve shaft and the valve body of the hydraulic control valve are relatively displaced about the axis in response to the operation of the steering wheel, whereby the hydraulic fluid from the hydraulic power source is displaced. The pressure is controlled for supply and discharge. Further, when the operating means is driven, the valve shaft and the valve body of the hydraulic control valve are relatively displaced along the axial direction, whereby the supply and discharge of the hydraulic fluid from the hydraulic source is controlled.

Therefore, not only can a different hydraulic steering system be constructed by using only this single hydraulic control valve, but if the operating means is driven as desired, for example, an automatic steering mode can be constructed or the steering system can be constructed. A variable force mechanism can be easily realized, and the structure is simple and inexpensive.

According to a third aspect of the present invention, there is provided a vehicle steering control device according to the second aspect, wherein the operating means includes a manual steering mode in which steering is performed by a driver operating a steering wheel. When the automatic steering mode is selected from the automatic steering modes that automatically detect and steer the traveling state, the valve shaft and the valve body of the hydraulic control valve are relatively displaced along the axial direction. I have.

According to a third aspect of the present invention, in the manual steering mode in which the driver operates the steering wheel by operating the steering wheel, when the steering wheel is operated, the valve shaft and the valve body of the hydraulic control valve are moved. Hydraulic pressure is supplied and discharged by being relatively displaced around the axis. On the other hand, in an automatic steering mode in which steering is automatically performed by detecting the running state of the vehicle, the actuating means is driven to relatively displace the valve shaft and the valve body of the hydraulic control valve along the axial direction. The pressure is controlled for supply and discharge.

As described above, it is easy to configure the automatic steering mode (selectively switching between the manual steering mode and the automatic steering mode) simply by driving the operating means as desired using a single hydraulic control valve. And the structure is simple and inexpensive.

According to a fourth aspect of the present invention, in the vehicle steering control device according to the second aspect, the operating means includes a valve shaft and a valve body of the hydraulic control valve based on a steering torque. Are relatively displaced along the axial direction.

In the vehicle steering control device according to the fourth aspect, the operating means is driven based on the steering torque by the driver operating the steering wheel, and the valve shaft and the valve body of the hydraulic control valve are moved along the axial direction. Relative displacement is performed, thereby controlling the supply and discharge of the hydraulic pressure. Therefore, it is possible to easily realize a steering force variable mechanism simply by driving the operating means as desired using a single hydraulic control valve, and the structure is simple and inexpensive.

[0017]

FIG. 6A and FIG. 6B show a vehicle steering controller 60 according to a first embodiment of the present invention.
Is shown.

The vehicle steering control device 60 includes a control valve 10. As shown in FIG. 1, the control valve 10 has a valve shaft 16 having a cylindrical shape, and is connected to a pinion shaft 15 so as to be integrally rotatable. The valve body 14 is fitted to the valve shaft 16 so as to be relatively rotatable around the axis and to be movable in the axial direction. This valve body 14 is used for the steering shaft 12.
And the steering shaft 12
Is mounted with a steering wheel 13.

A torsion bar 18 is arranged at the axis of the valve shaft 16. One end of the torsion bar 18 is connected to the steering shaft 12 and the other end is connected to the pinion shaft 15. That is, the steering shaft 12 is connected to the torsion bar 1
When the torsion bar 18 is twisted by the turning operation of the steering wheel 13, it is connected to the valve shaft 16 and the steering shaft 12 connected to the pinion shaft 15. A relative angular displacement is generated between the valve body 14 and the valve body 14.

An annular groove 2 is formed on the outer peripheral surface of the valve body 14.
0A, 20B and 20C are formed at predetermined intervals in the axial direction, the central annular groove 20B is connected to the hydraulic pump 52, and the axially upper annular groove 20A is connected to, for example, the right oil chamber 42 of the power cylinder 40. The lower annular groove 20 </ b> C in the axial direction is connected to, for example, a left oil chamber 44 of the power cylinder 40. A return oil hole 19 is formed in the valve shaft 16 at a portion that does not correspond to the valve body 14, and is connected to the reservoir tank 21.
Therefore, the oil liquid discharged from the hydraulic pump 52 is supplied to the control valve 10 (the valve body 14 and the valve shaft 16) and is returned to the reservoir tank 21.

As shown in detail in FIG.
Land portions 22 and concave grooves 24 extending in the axial direction
And are alternately formed along the circumferential direction. The land portion 22 and the concave groove 24 are spirally formed along the axial direction of the valve body 14. Also valve body 1
4, a pressure oil hole 26 for introducing hydraulic pressure from the hydraulic pump 52 into the control valve 10 through the central annular groove 20B.
Are formed in a radial direction of the land portion 22. Also,
An oil suction / discharge oil hole 28 communicating with one annular groove 20A for sucking / discharging oil pressure in, for example, a right oil chamber 42 of the power cylinder 40 is formed in the concave groove 24, and sucks / discharges oil in a left oil chamber 44 of the power cylinder 40, for example. An oil suction / discharge hole 30 communicating with the other annular groove 20 </ b> C is formed in the concave groove 24.

On the other hand, on the outer peripheral surface of the valve shaft 16,
The land portions 32 and the concave grooves 34 extending in the axial direction are alternately formed along the circumferential direction. As shown in FIG. 4, the land portion 32 and the concave groove 34 are spirally formed along the axial direction of the valve shaft 16, similarly to the land portion 22 and the concave groove 24 formed on the valve body 14. . In the valve shaft 16, a communication oil hole 36 for guiding the pressure oil to the inner peripheral space 38 of the valve shaft 16 is formed in a concave groove 34 facing the land 22 where the pressure oil hole 26 of the valve body 14 is not formed. It is formed through.

When the torsion bar 18 is not twisted (neutral state of the steering wheel 13), the groove 24 of the valve body 14 and the land 32 of the valve shaft 16 are formed between the valve shaft 16 and the valve body 14. As shown in FIG. 3, they face each other so that their central portions in the circumferential direction coincide. Thus, in the neutral state of the steering wheel 13, as shown in FIG.
A predetermined gap 39 is formed between the land 32 and the land 22 of the valve body 14 on both sides in the circumferential direction. As shown in FIG. 5B, the gap 39 serves as a throttle when the valve shaft 16 and the valve body 14 rotate relative to each other around the axis, and further, as shown in FIG.
As shown in FIG. 5, the valve shaft 16 and the valve body 14 serve as a throttle when relatively moving along the axial direction.

As shown in FIGS. 1 and 2, a lower end of the valve shaft 16 is provided with a rotating ring 46 constituting an operating means.
Is provided. A feed screw portion 48 is provided around the rotary ring 46, and a worm wheel 50 is screwed thereto. Therefore, the worm wheel 50
Is rotated, the rotary ring 46 is moved in the axial direction by the action of the feed screw portion 48, and thereby the valve shaft 16 is moved in the axial direction. Also,
The worm wheel 50 is meshed with a worm gear 56 of a motor 54 constituting an operating means.
Is driven to rotate the worm wheel 50.

The motor 54 is connected to a controller (not shown), and when the automatic steering mode is selected, the motor 5 is driven in accordance with the steering direction in the automatic steering mode.
4 can be driven and controlled.

Next, the operation of the first embodiment will be described. First, a description will be given of a case where the vehicle steering control device 60 is operated in a manual steering mode in which steering is performed by a driver's steering wheel operation.

In this manual steering mode, the steering wheel 13 is mechanically moved to the control valve 10 as shown in FIG.
Connected.

Here, the pressure oil supplied from the hydraulic pump 52 is introduced into the concave groove 34 of the valve shaft 16 through the central annular groove 20B and the pressure oil hole 26 of the control valve 10, and the periphery of the concave groove 34 It is introduced into the groove 24 of the valve body 14 adjacent on both sides through the gap 39 on both sides in the direction.
The pressure oil introduced into the concave groove 24 passes through the communication oil hole 3 through a gap 39 on the opposite side of the concave groove 34 to the concave groove 34.
6 is returned to the reservoir tank 21 via the communication oil hole 36 and the inner peripheral space 38.

When the steering is in a neutral state,
Since the torsion bar 18 is not twisted, FIG.
As shown in (A), the opening areas of the gaps 39 located on both sides in the circumferential direction of the concave groove 34 facing the pressure oil hole 26 become equal. At this time, there is no pressure difference between the concave grooves 24 on both sides of the land portion 22 in which the pressure oil hole 26 is formed, and the pressure in the right oil chamber and the pressure in the left oil chamber of the power cylinder 40 become equal. Thus, no assist force is generated in the power cylinder 40.

When the steering wheel is rotated and the torsion bar 18 is twisted, the valve body 14
As shown in FIG. 5B, there is a difference in the opening area of the gap 39 on both sides of the concave groove 34 in the circumferential direction. This allows
A pressure difference is generated by narrowing one of the gaps 39 between the concave grooves 24 on both sides of the land portion 22 in which the pressure oil hole 26 is formed, and a pressure difference also occurs between the two oil chambers of the power cylinder 40 connected thereto. As a result, an assist force is generated in the steering direction.

On the other hand, in the automatic steering mode in which the steering state is detected and the steering is automatically performed, the steering wheel 13 is separated from the control valve 10 as shown in FIG. 6B.

Here, the motor 5 is controlled based on the automatic steering signal.
When the motor 4 is driven, the worm wheel 50 rotates, and the rotary ring 46, that is, the valve shaft 16 is moved in the axial direction by the action of the feed screw 48. This allows
A relative axial displacement occurs between the valve body 14 and the valve shaft 16, resulting in a difference in the opening area of the gap 39 on both circumferential sides of the concave groove 34, as shown in FIG. Thereby, one gap 39 is narrowed between the concave grooves 24 on both sides of the land portion 22 in which the pressure oil hole 26 is formed, so that a pressure difference is generated, and the pressure difference is also generated between the two oil chambers of the power cylinder 40 connected thereto. The pressure difference causes a steering force in the steering direction, and the steered wheels are steered.

As described above, in the vehicle steering control device 60, the automatic steering mode can be configured by simply driving the motor 54 as desired using the single control valve 10 (the manual steering mode and the automatic steering mode are switched). (Selective switching) can be easily realized, and the structure is simple and inexpensive. Therefore, there is no need to provide an automatic steering hydraulic system used in the automatic steering mode, and the structure is simple and inexpensive.

Next, a second embodiment of the present invention will be described. Note that components that are basically the same as those in the first embodiment are given the same reference numerals as in the first embodiment, and descriptions thereof are omitted.

FIG. 7 shows the overall configuration of a vehicle steering control device 70 according to a second embodiment of the present invention.

The basic configuration of the vehicle steering control device 70 is the same as that of the vehicle steering control device 60 described above.
The drive of a motor 54 constituting an operating means for moving the valve shaft 16 along the axial direction is controlled based on the steering torque.

Therefore, the vehicle steering control device 70
For example, when it is desired to increase the steering force while the vehicle is running at high speed, the motor 54 drives the valve shaft 1
6 is moved along the axial direction to cause a relative axial displacement between the valve body 14 and the valve shaft 16. As a result, a difference occurs in the opening area of the gap 39 on both sides in the circumferential direction of the concave groove 24 (concave groove 34) on both sides of the land portion 22 where the pressure oil hole 26 is formed. As a result, the relative displacement between the valve body 14 and the valve shaft 16 (displacement around the axis) due to the operation of the steering wheel 13 is changed by the relative displacement between the valve body 14 and the valve shaft 16 (the axis (Displacement along the direction). As a result, as shown in FIG. 8, the substantial opening area of the gap 39 is increased, for example, and as a result, the hydraulic pressure is reduced and the steering force can be increased.

For example, when it is desired to reduce the steering force at the time of stationary steering or the like, the motor 54 is driven in a direction opposite to the above to move the valve shaft 16 along the axial direction. In addition to the relative displacement (displacement around the axis) between the valve body 14 and the valve shaft 16 due to the operation, the relative displacement between the valve body 14 and the valve shaft 16 (displacement along the axial direction) due to the driving of the motor 54 ) Also acts, and as a result, the hydraulic pressure is increased and the steering force can be reduced.

As described above, in the vehicle steering control device 70, the motor 54 is driven based on the steering torque by the driver operating the steering wheel 13 to control the control valve 10.
The valve shaft 16 and the valve body 14 are relatively displaced along the axial direction, thereby controlling the supply and discharge of the hydraulic pressure. Therefore, by simply driving the motor 54 as desired using the single control valve 10, a steering force variable mechanism can be easily realized, and the structure is simple and inexpensive.

[0040]

As described above, the vehicle steering control device according to the present invention can realize a simple and inexpensive structure for configuring, for example, an automatic steering mode or a variable steering force mechanism by hydraulic control. It has an excellent effect.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view along an axis of a control valve applied to a vehicle steering control device according to a first embodiment of the present invention.

FIG. 2 is a schematic perspective view showing a relationship between a rotating ring, a worm wheel, and a motor applied to the vehicle steering control device according to the first embodiment of the present invention.

FIG. 3 is a schematic half-sectional view perpendicular to an axis of a control valve applied to the vehicle steering control device according to the first embodiment of the present invention.

FIG. 4 is a schematic perspective view of a valve shaft of a control valve applied to the vehicle steering control device according to the first embodiment of the present invention.

FIG. 5 is a schematic sectional view showing a correspondence relationship between a land portion of a valve shaft of a control valve applied to the vehicle steering control device according to the first embodiment of the present invention and a concave groove of a valve body. is there.

FIG. 6 is an overall configuration diagram of a vehicle steering control device according to the first embodiment of the present invention.

FIG. 7 is an overall configuration diagram of a vehicle steering control device according to a second embodiment of the present invention.

FIG. 8 shows a relationship between a valve operating angle and a valve opening area of a control valve applied to a vehicle steering control device according to a second embodiment of the present invention, in which a valve shaft and a valve body are arranged only around an axis. FIG. 7 is a diagram illustrating a difference between a case where relative displacement is performed and a case where relative displacement is performed around an axis and along an axial direction.

[Explanation of symbols]

 Reference Signs List 10 control valve 12 steering shaft 14 valve body 16 valve shaft 18 torsion bar 24 concave groove (valve groove) 32 land (valve groove) 39 gap 46 rotating ring (operating means) 48 feed screw (operating means) 50 worm wheel ( Operating means) 54 Motor (operating means) 60 Vehicle steering control device 70 Vehicle steering control device

Claims (4)

[Claims] 1. A valve body comprising a valve shaft and a valve body having spiral valve grooves facing each other and capable of being relatively displaced around an axis and along an axial direction, and a hydraulic pressure is generated by the relative displacement of the valve shaft and the valve body. A vehicle steering control device provided with a hydraulic control valve for controlling the supply and discharge of air. 2. The hydraulic control valve according to claim 1, wherein the hydraulic control valve is disposed in a steering mechanism for connecting a steering wheel and a steered wheel, and the steering shaft operates to relatively displace the valve shaft and the valve body around an axis. 2. The vehicle steering control device according to claim 1, further comprising an actuating means for relatively displacing the valve shaft and the valve body of the valve along the axial direction. 3. An automatic steering mode is selected from a manual steering mode in which steering is performed by a driver's steering wheel operation and an automatic steering mode in which a driving state of a vehicle is detected and steering is automatically performed. 3. The vehicle steering control device according to claim 2, wherein the valve shaft and the valve body of the hydraulic control valve are relatively displaced along the axial direction. 4. The steering control device for a vehicle according to claim 2, wherein the operating means relatively displaces a valve shaft and a valve body of the hydraulic control valve in an axial direction based on a steering torque. .