JPH1035521A - Steering controller for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular steering controller capable of providing good steering feeling by a stable frictional force even if a valve body is tilted, reducing the number of part items and costs and increasing assembling performance. SOLUTION: In a control valve 10, s disk spring 52 attached to a valve shaft 16 is supported to be swung around an axis orthogonal to that of a pin 17 by locking of a pawl part 54 in the return oil hold 19 of the valve shaft 16 and press-contacted with the upper end surface of a valve body 14. When the valve shaft 16 is displaced with respect to the valve body 14, the disk spring 52 produces rotational resistance by a frictional force, thereby hysterisis is produced in the characteristic of a relative displacement angle θ-steering torque T, steering feeling is improved at the time of its start and a steering holding force is reduced. Further, even if the valve body 14 is tilted by the pin 17 as a fulcrum, the disk spring 52 follows this tilting and the frictional force is stably produced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering control device for a vehicle such as an automobile, and more particularly to a vehicle steering control having a hydraulic control valve for controlling supply and discharge of a hydraulic pressure by a relative displacement between a valve shaft and a valve body. Related to the device.

[0002]

2. Description of the Related Art As a steering control device for a vehicle such as an automobile (for example, a hydraulic power steering device), a power steering device having a hydraulic control valve is known (for example, Japanese Utility Model Laid-Open No. 5-55858). ).

[0003] In the power steering apparatus disclosed in this publication, the hydraulic control valve is a so-called rotary valve having a valve shaft and a valve body, and the hydraulic pressure is supplied by the relative displacement between the valve shaft and the valve body. Discharge control can be performed. In this hydraulic control valve, a snap ring is locked on the outer periphery of the valve shaft. Further, a friction washer and the friction washer are provided between the end face of the valve body and the snap ring in the direction of the valve body. A biasing spring is disposed. Thereby, a frictional force is applied at the time of relative displacement between the valve shaft and the valve body. Thereby, the rattling of the valve body is suppressed.

However, in a power steering apparatus using such a hydraulic control valve, the valve body constituting the hydraulic control valve is connected to the pinion shaft via a pin. However, a tilt occurs. For this reason, the friction washer also inclines, and as a result, the pressing force between the valve body and the friction washer becomes uneven, so that the frictional force is not stabilized, and there is a disadvantage that the steering feeling is impaired.

Further, since the hydraulic control valve uses a plurality of components such as a snap ring, a friction washer, and a spring to obtain a frictional force as described above, the number of components is large and the cost is high. However, there was also a problem of poor assemblability.

[0006]

In view of the above facts, the present invention can provide a good steering feeling with a stable frictional force even if the valve body is inclined, and further reduce the number of parts. It is an object of the present invention to provide a vehicle steering control device that is low in cost and has improved assemblability.

[0007]

According to a first aspect of the present invention, there is provided a vehicle steering control device comprising: a valve shaft connected to a steering shaft to which a steering wheel is attached; and a valve shaft connected to the valve shaft via a torsion bar. A valve body connected to a pinion shaft via a pin, 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 a vehicle steering control device controlled by a control valve, the valve body is supported on the valve shaft so as to swing around an axis orthogonal to an axis of the valve body and a pin, facing an axial end surface of the valve body, A frictional force applying member is slidably pressed against the axial end surface of the body with a predetermined urging force.

[0008] In the vehicle steering control device according to the first aspect, a frictional force applying member supported by the valve shaft is slidably pressed against the axial end surface of the valve body by a predetermined urging force. When the steering wheel is operated, the valve shaft and the valve body of the hydraulic control valve are relatively displaced in response to this, whereby the supply and discharge of the hydraulic fluid from the hydraulic source is controlled.

In this case, when the valve shaft is rotated by the steering operation, the frictional force applying member supported by the valve shaft slides on the axial end surface of the valve body, and generates rotational resistance due to the frictional force. As a result, hysteresis occurs in the characteristic of the relative displacement angle θ-steering torque T, the feeling of response at the start of steering operation (at the time of turning) is improved, and the steering force at the time of steering wheel steering is reduced. A good steering feeling can be obtained.

In this case, in the vehicle steering control device according to the first aspect, the frictional force applying member is supported by the valve shaft so as to be swingable about an axis perpendicular to the axis of the valve body and the pin. Even if the valve body connected to the pinion shaft via the pin tilts using the pin as a fulcrum, the frictional force imparting member swings and follows the tilt of the valve body. As a result, the pressing force between the frictional force applying member and the valve body becomes uniform, the frictional force is stabilized, and a good steering feeling can be obtained.

Further, in the vehicle steering control device according to the first aspect, since the rotation resistance is generated by the frictional force by the single frictional force applying member supported by the valve shaft, the number of parts is reduced. The cost is reduced and the assemblability is improved. Further, if the urging force of the frictional force applying member is changed, the frictional force between the frictional force applying member and the axial end surface of the valve body is changed, and the hysteresis characteristic can be adjusted.

As described above, in the vehicle steering control device according to the first aspect, a good steering feeling can be obtained by a stable frictional force even if the valve body is tilted, and the number of parts is reduced. As a result, the cost is reduced and the assemblability is improved.

According to a second aspect of the present invention, in the vehicle steering control device according to the first aspect, the vehicle steering control device is provided at a portion of the valve shaft that does not correspond to the valve body for discharging pressure oil. The frictional force applying member is locked in the returned oil hole.

In the vehicle steering control device according to the second aspect, there is no need to provide a new supporting means such as a mounting hole for supporting the frictional force applying member on the valve shaft, and the structure is simplified.

According to a third aspect of the present invention, in the vehicle steering control device according to the first or second aspect, the frictional force applying member is formed in a ring shape and has an inner peripheral wall. It is characterized in that a pair of claw portions, which serve as support portions for the valve shaft on a diagonal line, are formed as protruding disc spring members.

According to the third aspect of the present invention, the pair of pawls formed on the disc spring member are engaged with the valve shaft, so that the disc spring member is orthogonal to the axis of the valve body and the pin. Is supported by the valve shaft so as to be able to swing around the axis of rotation. Therefore, the configuration as the frictional force applying member can be realized by the disc spring member, and the structure for reliably supporting the disc spring member in a swingable manner is simplified.

[0017]

FIG. 1 shows the overall configuration of a vehicle steering control device according to an embodiment of the present invention.

The vehicle steering control device includes a control valve 10. The control valve 10 has a cylindrical valve housing 12, and a valve body 14 is disposed in the valve housing 12 so as to be relatively rotatable. The valve body 14 has a cylindrical shape, and is connected to a pinion shaft 15 (output shaft) via a pin 17 so as to be integrally rotatable.

The valve shaft 14 is mounted on the valve body 14.
6 are fitted so as to be relatively rotatable. The valve shaft 16 is connected to an input shaft (not shown).

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 valve shaft 16 (input shaft), and the other end is connected to the pinion shaft 15. That is, the valve shaft 16 (input shaft) is connected to the pinion shaft 15 via the torsion bar 18, and is connected to the pinion shaft 15 when the torsion bar 18 is twisted by the turning operation of the steering wheel. A relative angular displacement is generated between the valve body 14 and the valve shaft 16 connected to the input shaft.

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 a hydraulic pump (not shown) via a hydraulic circuit, and the upper annular groove 20A is a power cylinder (not shown). For example, the lower annular groove 20C in the axial direction is connected to, for example, a left oil chamber of the power cylinder.

As shown in FIG. 4, on the inner peripheral surface of the valve body 14, a land portion 22 and a concave groove 24 extending in the axial direction are formed.
They are formed alternately along the circumferential direction. A pressure oil hole 26 for introducing hydraulic pressure from a hydraulic pump into the control valve 10 through a central annular groove 20 </ b> B is formed through the valve body 14 in the radial direction of the land 22. Further, a suction / discharge oil hole 28 communicating with one annular groove 20A for sucking / discharging oil pressure in, for example, a right oil chamber of the power cylinder is formed in the concave groove 24, and the other oil suction / discharge oil is discharged to, for example, a left oil chamber of the power cylinder. An oil suction / discharge hole 30 communicating with the annular groove 20 </ b> C is formed in the concave groove 24.

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. In the valve shaft 16, a communication oil hole 3 for guiding pressure oil to an inner peripheral space 38 of the valve shaft 16 is formed in a concave groove 34 facing the land portion 22 where the pressure oil hole 26 of the valve body 14 is not formed.
6 are formed through.

Further, a return oil hole 19 for guiding pressure oil to a reservoir tank (not shown) is formed through a portion of the valve shaft 16 that does not correspond to the valve body 14.

The valve shaft 16 and the valve body 1
4, when the torsion bar 18 is not twisted (the steering is in a neutral state), the concave groove 24 of the valve body 14 and the land 32 of the valve shaft 16
As shown in the figure, the center parts in the circumferential direction are aligned and opposed,
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. This gap 39 becomes a throttle when the valve shaft 16 and the valve body 14 rotate relative to each other.

Further, as shown in FIG. 5, a steering reaction force control unit 40 is provided in the valve housing 12 below the valve body 14 in the figure. Steering reaction force control unit 40
Has a plunger holder 42 into which the lower end of the valve shaft 16 is fitted.

The plunger holder 42 has a pair of recesses 48 formed on the outer peripheral side, and a space between the recesses 48 and the valve housing 12 is a hydraulic chamber 50. Also,
In the plunger holder 42 corresponding to the hydraulic chamber 50, one pair and two pairs (four) of plungers 46 are slidably held. Each of these plungers 46 faces one side of the hydraulic chamber 50. A projection 46 </ b> A is formed on the side of each plunger 46 opposite to the hydraulic chamber 50, and faces each side of a pair of flat wings 44 formed at the lower end of the valve shaft 16. For this reason, the plunger 46 causes the protrusion 46 </ b> A due to the pressure increase of the hydraulic chamber 50.
Presses the wings 44.

On the other hand, as shown in FIGS. 2 and 3, a disc spring 52 as a frictional force applying member (disc spring member) is arranged near the upper end surface in the axial direction of the valve body 14.
The disc spring 52 is formed in a ring shape (dish shape), and a pair of claw portions 54 are formed on the inner peripheral wall so as to project diagonally. The claw portion 54 is locked in the above-described return oil hole 19 formed in the valve shaft 16, whereby the disc spring 52 is orthogonal to the axis of the valve body 14 and the pin 17 (in FIG. The valve body 16 is supported by the valve shaft 16 so as to be swingable about an axis (from the front side to the back side) and slidably pressed against an axial end face of the valve body 14 with a predetermined urging force.

Next, the operation of the present embodiment will be described. In the control valve 10 (vehicle steering control device) having the above-described configuration, the pressure oil supplied from the hydraulic pump is diverted by the diverter valve, and then is passed through the central annular groove 20B and the pressure oil hole 26 of the control valve 10. It is introduced into the concave groove 34 of the valve shaft 16 and is introduced into the concave groove 24 of the valve body 14 adjacent on both sides through the gap 39 on both sides in the circumferential direction of the concave groove 34. The pressure oil introduced into the groove 24 is introduced into the groove 34 communicated with the communication oil hole 36 through a gap 39 on the side of the groove 24 opposite to the groove 34, and the communication oil hole 3 is formed.
6. Returned to the reservoir tank via the inner peripheral space 38.

When the steering is in a neutral state,
Since the torsion bar 18 is not twisted, the opening areas of the gaps 39 located on both circumferential sides of the concave groove 34 facing the pressure oil hole 26 are equal as shown in FIG. At this time, no pressure difference occurs 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 become equal, No assist force is generated in the power cylinder.

When the steering wheel is rotated and the torsion bar 18 is twisted, the valve body 14
Relative angular displacement occurs between the valve shaft 16 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 a result, one gap 39 (a gap on the opposite side in the rotation direction) 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 power connected to these is reduced. A pressure difference also occurs between the two oil chambers of the cylinder, and an assist force is generated in the steering direction.

Further, the amount of oil increases as the vehicle speed increases, and the reaction force applied to the steering reaction force control unit 40 (the hydraulic chamber 50) increases. Thereby, the reaction force (the arrow F _{R in} FIG. 5) by the plunger 46 increases. Therefore, as the steering force, the reaction force of the plunger 46 acts in addition to the torsion torque of the torsion bar 18, so that
A stable steering feeling with a sense of response is obtained.

Here, in the control valve 10 (vehicle steering control device), a disc spring 52 supported by the valve shaft 16 is slidably pressed against the axial end face of the valve body 14 by a predetermined urging force. When the valve shaft 16 is rotated by the steering operation, the disc spring 52 supported by the valve shaft 16 slides on the axial end surface of the valve body 14 to generate rotational resistance due to frictional force. As a result, hysteresis occurs in the characteristic of the relative displacement angle θ-steering torque T, the feeling of response at the start of steering operation (at the time of turning) is improved, and the steering force at the time of steering wheel steering is reduced. A good steering feeling can be obtained.

In the control valve 10 (vehicle steering control device), the disc spring 52 is supported by the valve shaft 16 so as to be swingable about an axis perpendicular to the axis of the valve body 14 and the pin 17. Therefore, even if the valve body 14 connected to the pinion shaft 15 via the pin 17 is tilted with the pin 17 as a fulcrum, the disc spring 52 swings and follows the tilt of the valve body 14. As a result, the disc spring 52 uniformly presses against the valve body 14 and the disc spring 5
The pressing force between the valve body 2 and the valve body 14 becomes uniform, the frictional force is stabilized, and a good steering feeling can be obtained.

Further, the control valve 10 (vehicle steering control device) has a configuration in which a single disc spring 52 supported on the valve shaft 16 generates rotation resistance due to frictional force, so that the number of parts is reduced. The cost is reduced and the assemblability is improved. Further, since the disc spring 52 has a configuration in which the claw portion 54 is locked in the return oil hole 19 formed in the valve shaft 16, new support means such as a special mounting hole for mounting the disc spring 52 is provided. There is no need to provide a slab, and the structure is simplified. Further, if the urging force of the disc spring 52 is changed, the frictional force between the disc spring 52 and the axial end surface of the valve body 14 is changed, and the hysteresis characteristic can be adjusted.

As described above, the control valve 1 according to the present embodiment
0 (vehicle steering control device), even if the valve body 14 is tilted, a good steering feeling can be obtained by a stable frictional force, and the number of parts is reduced to reduce the cost, and The performance is also improved.

[0037]

As described above, the steering control device for a vehicle according to the present invention can obtain a good steering feeling with a stable frictional force even if the valve body is tilted, and the number of parts can be reduced. It has an excellent effect of reducing the cost and reducing the cost, and improving the assemblability.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an entire configuration of a control valve according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a correspondence relationship between a valve body, a valve shaft, a disc spring, and the like of the control valve according to the embodiment of the present invention.

FIG. 3 is a perspective view showing a correspondence relationship between a valve body, a valve shaft, a disc spring, and the like of the control valve according to the embodiment of the present invention, with the disc spring removed.

FIG. 4 is a schematic half sectional view taken along a direction perpendicular to an axis of the control valve according to the embodiment of the present invention.

FIG. 5 is a sectional view perpendicular to an axis of a steering reaction force control unit of the control valve according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 control valve (vehicle steering control device) 12 valve housing 14 valve body 15 pinion shaft 16 valve shaft 17 pin 18 torsion bar 19 return oil hole 52 disc spring (frictional force applying member, disc spring member) 54 claw

Claims (3)

[Claims] A valve shaft connected to a steering shaft to which a steering wheel is attached;
A valve body connected via a pin to a pinion shaft connected to the valve shaft via a torsion bar, and a hydraulic control valve for controlling supply / discharge of hydraulic pressure by a relative displacement between the valve shaft and the valve body. Have
A vehicle steering control device that controls an oil liquid from a hydraulic pressure source by the hydraulic control valve, wherein the hydraulic control valve is configured to swing around an axis orthogonal to the axis of the valve body and the pin, facing an axial end surface of the valve body. A vehicle steering control device, comprising: a frictional force applying member supported by the valve shaft and slidably pressed against an axial end surface of the valve body with a predetermined urging force. 2. The frictional force applying member is engaged with a return oil hole provided in a portion of the valve shaft that does not correspond to the valve body for discharging pressure oil. Vehicle steering control device. 3. The frictional force applying member is a disc spring member formed in a ring shape and formed with a pair of claws protruding on a diagonal line of an inner peripheral wall as a support portion for the valve shaft. The vehicle steering control device according to claim 1 or 2, wherein: