JP2000072013A - Hydraulic control valve with torque transmission direction changing means - Google Patents

Abstract

(57) [Problem] To integrate a hydraulic control valve and a torque transmission direction changing means in the middle of a steering shaft system to reduce a space occupied in a vehicle, increase a degree of freedom of a vehicle layout, and transmit rotation. Configure so that it can be performed properly. SOLUTION: A hydraulic control valve 11 by a rotary flow path switching valve 26 for driving and controlling a power cylinder, and a torque transmission direction changing means 12 provided in the middle of a steering shaft system.
Is provided. It is integrally connected to the valve body 21 of the hydraulic control valve and the gear body 41 of the torque transmission direction changing means.
A transmission shaft 23, which is connected to an input shaft 22 on the steering wheel side via a rotary flow path switching valve, extends through the valve body toward the gear body, and is connected to an output shaft rotatably supported by the gear body. On the other hand, the shafts face each other from a direction substantially perpendicular to the shafts, and the two shafts are connected to the gear coupling means 50, 51 in the internal space.
Gear coupling. The output shaft is supported so as to be movable in the axial direction, and an adjusting mechanism 40 capable of adjusting the amount of movement of the output shaft in the axial direction is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power steering apparatus for transmitting a steering wheel to a steering link mechanism by using a steering gear by a steering operation of a steering wheel to steer left and right steering wheels. The present invention relates to a hydraulic control valve for driving and controlling a power cylinder, which is provided with a torque transmission direction changing unit.

[0002]

2. Description of the Related Art For example, a rack-and-pinion type power steering device meshes with a rack shaft arranged along the width direction between left and right front wheels (steering wheels) of a vehicle (vehicle). A pinion shaft that has a pinion and is connected to the handle shaft side of the steering handle.
Further, a power cylinder is provided in a part of the steering link mechanism between the left and right steering wheels together with the steering gear including the rack and the pinion, so that a steering assist force is applied to the steering link mechanism.

[0003] Further, a hydraulic control valve having a rotary flow path switching valve structure is provided on the pinion shaft portion. The hydraulic control valve detects a steering operation state of a steering handle and detects a left or right cylinder of the power cylinder. The supply of the pressure oil to the chamber is controlled to be distributed.

In the power steering apparatus described above, the rotational displacement caused by the steering operation of the steering wheel is converted into a linear displacement in the axial direction of the rack shaft by the steering gear, and the linear displacement is transmitted through the steering link mechanism including the rack shaft. ,
The right steering wheel is steered in a desired direction, and the pressure oil distributed and controlled by the hydraulic control valve is supplied to the left and right cylinder chambers of the power cylinder, whereby the steering assist force in a required direction is provided. It is provided to a steering link mechanism to steer left and right steered wheels.

[0005]

However, when the above-described power steering device is mounted on a vehicle, there are the following problems, particularly in terms of occupied space.

One is that a valve mechanism having the hydraulic control valve is integrally connected to a part of a power steering main body having a rack constituting a steering link mechanism between steered wheels of a vehicle. Therefore, when assembled into a vehicle, there is a problem that the entire unit including the power steering main body and the valve mechanism becomes large, and there is a restriction in terms of space.

In particular, a hydraulic pipe is provided around the above-mentioned valve mechanism and the power steering main body, and a working space for a tool such as a wrench for tightening and removing bolts and nuts attached to each member. Therefore, the occupied space as a whole becomes large, and it is necessary to arrange them so as not to interfere with the vehicle body frame and other in-vehicle devices.

[0008] Around the power steering body, frames constituting a vehicle body such as an engine, an exhaust pipe, a cross member, and other connecting members including other in-vehicle devices and hydraulic piping are mounted at high density. ing. In particular, securing such a mounting space is a major problem for small passenger cars. Therefore, it is desired to reduce the size of the main body of the power steering device so as to be easily mounted on a vehicle in consideration of the relationship with these various mechanisms.

Although it is conceivable that the above-mentioned valve mechanism is formed as a separate body, simply dividing the valve mechanism increases the number of components such as a valve body and a transmission shaft.
Also, incorporation into the steering shaft system may cause troubles such as complicated work and complicated structure. For this reason, it is desired to take some measures that can simplify the structure and assemblability of the valve mechanism in addition to the structure of the steering shaft system.

The present invention has been made in view of such circumstances, and a hydraulic control valve provided on a steering shaft system is combined with another mechanism to share components and thereby simplify the structure and reduce the size. While promoting
Simplify the overall structure of the power steering device, reduce the size of each part, especially the space occupied by the power steering body as much as possible, and incorporate the power steering device into space-constrained vehicles such as small passenger cars. It is an object of the present invention to obtain a hydraulic control valve with a torque transmission direction changing means that can improve workability and allow a degree of freedom in a vehicle-mounted layout.

[0011]

According to a first aspect of the present invention, there is provided a hydraulic control valve having a torque transmission direction changing means, which is provided with a steering link mechanism through a steering link mechanism. A power steering body having a steering gear for turning the right steering wheel, a power cylinder for applying a steering assist force to the steering link system by a steering operation, and driving control of the power cylinder by a steering operation of a steering wheel. A hydraulic control valve, and a torque transmitting direction changing means provided in a steering shaft system for transmitting a steering operation state from a steering handle to a steered wheel side, wherein the hydraulic control valve is formed separately from the power steering main body. The valve body of the hydraulic control valve is connected to a gear In connection with the gear, a transmission shaft connected to an input shaft that is rotated by a steering operation via a rotary flow path switching valve extends through the valve body toward the gear body, and is rotatably mounted on the gear body. The transmission shaft and the output shaft are gear-coupled to each other by a gear coupling means within an internal space of the gear body, and the output shaft is connected to the gear body. And an adjusting mechanism capable of adjusting the amount of movement of the output shaft in the axial direction.

According to a second aspect of the present invention, there is provided a hydraulic control valve with a torque transmitting direction changing means, wherein a steering gear portion for turning left and right steering wheels by a steering operation, and a steering assist force to a steering link system by the steering operation. A power steering body having a power cylinder to be operated, a hydraulic control valve for drivingly controlling the power cylinder by a steering operation, and a torque transmission direction changing means provided in the middle of a steering shaft system from a steering wheel to a steered wheel. The hydraulic control valve is formed separately from the power steering main body, and when the valve body of the hydraulic control valve is connected to the gear body of the torque transmitting direction changing means, a rotary flow path is switched to an input shaft which is rotated by a steering operation. The transmission shaft connected via a valve passes through the valve body and The transmission shaft and the output shaft are gear-coupled by a gear coupling means in an internal space of the gear body. A part of a return side flow path to a tank in a rotary flow path switching valve of a valve body is connected to an internal space of a gear body provided with a gear coupling means for the transmission shaft and the output shaft. .

According to a third aspect of the present invention, there is provided a hydraulic control valve with a torque transmitting direction changing means according to the second aspect, wherein the hydraulic control valve with the torque transmitting direction changing means has a transmission shaft side of a gear at an output shaft in a gear body. A back pressure chamber communicating with an internal space connected to a return flow path to the tank is provided at a shaft end opposite to a meshing portion with the gear.

According to the present invention, when the hydraulic control valve is separated from the power steering main body and integrally connected to the torque transmission direction changing means in the middle of the steering shaft system, the respective bodies (valve body and gear body) are connected. Then, it can be used as a lid member for closing the opening of each other, or a common transmission shaft can be used, and further, torque transmission in a direction substantially orthogonal to the transmission shaft and the output shaft can be performed by using a gear coupling means such as a bevel gear. At the same time, the backlash at the gear coupling portion is absorbed by the adjusting mechanism provided at the shaft end of the output shaft.

According to the present invention, the lubricating oil can be shared by guiding the tank pressure from the rotary flow passage switching valve side in the valve body into the gear body integrally connected to the valve body. Further, the back pressure chamber using the tank pressure is formed at the shaft end of the output shaft to constitute the adjusting mechanism, so that the backlash can be absorbed by the automatic preload.

Here, in the hydraulic control valve with the torque transmitting direction changing means, the gear coupling means refers to, for example, a bevel gear or a zelol gear, but is not limited thereto.

The valve body constituting the above-mentioned hydraulic control valve is integrally connected to the steering handle side of the gear body constituting the torque transmitting direction changing means in the steering shaft system. However, it is not limited to this.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic diagram showing the entirety of a power steering apparatus using a hydraulic control valve with a torque transmitting direction changing means according to the present invention, and FIG. 2 is a torque transmitting direction according to the present invention. It is a longitudinal section showing one embodiment of a hydraulic control valve with conversion means.

FIG. 3 is an enlarged cross-sectional view of a main part of FIG. 2, which is a main part of the joint between the valve body and the gear body.
4 is a sectional view taken along the line IV-IV in FIG. 3, FIG. 5 is a side view showing the appearance of FIG. 2, and FIG. 6 is a plan view of FIG.

In FIG. 1, a power steering device generally designated by reference numeral 1 is a power steering device 4 which constitutes a steering link mechanism 3 between left and right steering wheels 2 and 2 (front wheels). It has. In the drawings, reference numerals 3a, 3a denote tie rods, and 3b, 3b denote tie rod arms, which are configured to transmit the movement of the steering link mechanism 3 to the left and right steering wheels 2, 2 to steer in a required direction. .

The power steering body 4 comprises a rack 7a and a pinion 8 for transmitting a steering operation transmitted from a steering handle 5 via a steering shaft system 6 to a rack shaft 7 constituting the steering link mechanism 3. A steering gear section 9 of a rack and pinion type and a power cylinder 10 for applying a steering assist force to the steering link mechanism by the steering operation are provided.

Reference numeral 11 denotes a hydraulic control valve. The hydraulic control valve 11 is adapted to control the left and right cylinder chambers (CL, CL) of the power cylinder 10 in accordance with a steering operation of the steering handle 5.
By controlling the distribution of the pressure oil by switching the oil path to CR), the power cylinder 10 is driven in a predetermined direction (steering operation direction) to generate the steering assist force. In addition,
As such a hydraulic control valve 11, for example, a rotary flow path switching valve may be used. In the figure, P is a hydraulic pump, and T is a tank.

The hydraulic control valve 11 has a torque transmitting direction changing means 12 (see FIGS. 2 and 3) provided in the middle of a steering shaft system 6 for transmitting a steering operation torque from the steering handle 5 to the steering gear portion 9. Are provided integrally. This torque transmission direction conversion means 12
Is transmitted in the transmission path of the steering operation force between the handle shaft 5a on the steering handle 5 side and the pinion shaft 8 having the pinion 8a of the steering gear portion 9 due to the mounting state on the vehicle, space, and other reasons. It is disposed in a portion where the path is bent. As the above-described torque transmission direction conversion means 12, a gear mechanism that changes the transmission direction, such as a bevel gear, is used.

According to the present invention, the above-described hydraulic control valve 11 is formed separately from the power steering main body 4 as shown in FIGS. 1 and 2, and the hydraulic control valve 11 is connected to the steering handle 5. It is disposed between the power steering main body 4 and the power steering main body 4. The valve body 21 of the hydraulic control valve 11 is shown in FIGS.
As shown in the figure, the torque transmitting direction converting means 12 is integrally connected to the gear body 41. In FIGS. 5 and 6, reference numeral 70 denotes a bolt for fastening and fixing the two bodies 21 and 41 in an integrally assembled state.

In the hydraulic control valve 11 with the torque transmitting direction changing means 12 described above, the hydraulic control valve section
As shown in FIG. 2, an input shaft 22 that is rotated by a steering operation of a steering handle in a valve body 21 and a transmission shaft 23 that is connected to the input shaft 22 so as to be relatively rotatable. It is constituted by a rotary flow path switching valve 26 comprising a rotor 24 and a sleeve 25 provided.

The input shaft 22 and the transmission shaft 23 are connected to each other by a torsion bar 27 so as to be relatively rotatable within a predetermined angle range. Is switched between the left and right chambers CL, CR, and the tank T. The transmission shaft 23 integrally having the sleeve 25 is
A pair of bearings 28,
It is rotatably supported by 29.

In the figure, 31 is a pump port, 32 is a tank port, 33 and 34 are output ports to the left and right chambers CL and CR of the cylinder, and these ports 31, 32, 33 and 33 are shown.
Is connected to a passage groove formed in the rotor 24 and the sleeve 25, and pressure oil is supplied with the passage switching,
Although it is discharged, its detailed structure and operation are widely known, and a detailed description thereof will be omitted.
A bearing 35 supports the input shaft 22. The input shaft 22 is supported by a bearing 36 in the transmission shaft 23.
Reference numeral 37 denotes a plug member for closing an opening on the input shaft 22 side in the shaft hole 21a of the valve body 21.

As shown in FIG. 2, the torque transmitting direction changing means 12 integrally connected to the hydraulic control valve 11
A gear body 41 is connected to the transmission shaft 23 of the valve body 21. The gear body 41 has an opening 41a with which the end 21b of the valve body 21 is engaged. An opening 41b is also formed in a direction orthogonal to the opening 41a, and a gear cover 42 for closing the opening 41b is provided. 5 and 6, reference numeral 75 denotes a bolt for fastening and fixing the gear cover 42 to the gear body 41.

In the gear body 41, an output shaft 43 for changing the direction of transmission of rotation of the transmission shaft 23 on the hydraulic control valve 11 side is supported so that the transmission shaft 23 and the axis are substantially orthogonal to each other. . In the figure, reference numerals 44 and 45 denote output shafts 4.
3 is a bearing for supporting. Since the output shaft 43 is supported at both ends by such bearings 44 and 45, and a bevel gear 50 (described later) as a gear means is provided between the output shaft 43 and the output shaft 43.
Smooth, axial transmission of each axis is obtained.

The transmission shaft 23 is connected to the valve body 21
And extends toward the gear body 41 side, and faces the output shaft 43 rotatably supported in the gear body 41 from a direction in which the axis is substantially orthogonal to the output shaft 43. A bevel gear 50 gear-coupled to transmit rotation between the transmission shaft 43 and the output shaft 23;
51 are provided. Incidentally, such gear coupling means is not limited to the bevel gear 50, and a zero roll gear may be used. In short, any off-axis gear that does not generate a component force may be used.

According to the present invention, the bevel gear 5 for connecting the transmission shaft 23 and the output shaft 43 in the gear body 41 is provided.
As shown in FIGS. 2 and 3, a part of the return-side flow path to the tank T in the rotary flow path switching valve 26 of the valve body 21 is provided in the internal space provided with The passage groove, the radial passage groove 25a formed in the sleeve 25, and the clearance between the bearing 29 communicate with each other.

When such a structure is adopted, the lubrication of the gear portion and the rotating portion in the gear body 41 is controlled by the hydraulic control valve 1.
1, the lubricating oil can be shared.

Further, when the hydraulic oil having the tank pressure on the hydraulic control valve 11 side is introduced into the gear body 41, the following advantages are obtained. That is, in the torque transmission direction changing means 12, it is desired that the meshing portions of the bevel gears 50 and 51, which are gear coupling means, reduce the backlash, smoothly transmit the torque, and improve the steering feeling.

Here, the gear chamber 4 in the gear body 41
When hydraulic oil is introduced to 1a, hydraulic pressure is generated in this chamber 41a. The hydraulic pressure causes the hydraulic control valve 1
A pressing force on the input shaft 22 on the steering wheel side acts on the transmission shaft 23 on the one side. The output shaft 43 is pressed by hydraulic pressure toward the steered wheels. This force is equal to the inner diameter of the lip of the oil seal adjacent to the bearing 44 to the magnitude of the hydraulic pressure.

The input shaft 22 is brought to a stable position by the pushing of the bearing 21a. The output shaft 43 is provided with a slight backlash in an adjusting screw portion between the output shaft 43 and an adjusting screw 48 described later, so that hydraulic pressure acts to reduce backlash of the gears 50 and 51. Therefore, according to such a configuration, it is possible to obtain an appropriate meshing state between the gears 50 and 51 and perform smooth torque transmission.

The output shaft 43 is movable in the axial direction, that is, the output shaft 43 and the adjusting screw 4
The gap between the adjusting screw 8 and the adjusting screw 8 may be, for example, a gap large enough to absorb a mounting error around the output shaft 43 and a processing error of the gears 50 and 51.

According to the present invention, the output shaft 43
Is provided with an adjusting mechanism 46 that is axially movably supported in the gear body 41 and that can adjust the amount of movement of the output shaft 43 in the axial direction. This adjustment mechanism 46
In the gear body 41, at the shaft end 43a of the output shaft 43 on the side opposite to the meshing portion of the gear 51 with the gear 50 on the transmission shaft 23 side, the internal space connected to the return-side flow path to the tank T is formed. It is configured by providing a back pressure chamber 47 that is in communication.

The back pressure chamber 47 is formed by being narrowed down by a clearance passage in a bearing 45 that supports the output shaft 43. According to such a back pressure chamber 47, the output shaft 43 is connected to the bevel gear 5
Since a force against the movement of the bevel gear 51 generated at the time of the meshing of the gears 0 and 51 can be given in a direction to reduce the backlash, the backlash of the bevel gears 50 and 51 is absorbed and the backlash is eliminated. Appropriate mesh transmission can be ensured.

That is, the force acting on the bevel gear 51 on the output shaft 43 by the back pressure chamber 47 is smaller than the force from the transmission shaft 23 and the bevel gear 50 in the direction in which the backlash is reduced (steering wheel side). Is also a pressing force due to a large hydraulic pressure. However, this pressing force is a force within a range in which mounting errors and gear processing errors can be absorbed.

According to the adjusting mechanism 46 utilizing such a back pressure chamber 47, the backlash is automatically adjusted, and proper meshing is ensured. In addition, such an adjusting mechanism 4
According to No. 6, it is practically advantageous because the mounting error of the bevel gears 50 and 51, the transmission shaft 23, the output shaft 43 and the like and the processing error of the gear can be absorbed by using the back pressure which can always be obtained.

For example, when a steering torque of 1 Kgm in a normal steering range is input to the transmission shaft 23, the bevel gears 50, 5
1 (the force of the output shaft 43 toward the back pressure chamber 47)
Is 13.3 Kgm. On the other hand, the pressing force obtained by the back pressure chamber 47 is 24.5 Kgm when a back pressure of 5 Kgf / cm ² is applied, and is always larger than the above-described meshing component force. Therefore, since the meshing tooth surfaces of the bevel gears 50 and 51 do not separate due to the pressing force by the hydraulic pressure, there is no noise problem such as rattling noise.

In the drawing, reference numeral 48 denotes a gear 50 on the transmission shaft 23 side.
And an adjustment screw for performing backlash adjustment at the time of initial setting of the gear 51 on the output shaft 43 side. This adjustment screw 4
8 is fixed at a predetermined adjustment position by a nut 48a screwed into an outer end protruding from the gear cover 42. In FIGS. 2 and 3, reference numeral 48b denotes a sealing material such as rubber;
c is a metal ring, which constitutes a seal washer structure for sealing the mounting portion of the adjusting screw 48,
7 is sealed at the outer end side. In addition, a seal member is not provided at a portion of the bearing 45 that supports the output shaft 43 on the inner end side of the back pressure chamber 47, and the back pressure chamber 47 and the gear chamber 41a are kept in communication. Needless to say.

In the adjusting mechanism 46 as described above, the output shaft 43 is adjusted to a state where the backlash in the bevel gears 50 and 51 becomes zero once, and then adjusted in a direction to increase the backlash. And, as described above, the back pressure chamber 4
Since the output shaft 43 is constantly receiving a force in the direction of reducing the backlash by the pressing force of 7, the appropriate backlash can be set without being affected by the backlash.

The appropriate clearance (play) provided in the above-mentioned adjusting mechanism 46 is normally closed in the backlash decreasing direction by the pressing force of the back pressure chamber 47. At the time of gear meshing interference due to an error or a mounting error, the output shaft 4 is pressed against the pressing force of the back pressure chamber 47.
3 helps in the direction of increasing backlash.

Therefore, according to the above-described configuration, even if an expensive gear such as a grinding gear is not used, the backlash of the gear does not generate rattle noise and the minimum backlash which does not adversely affect the performance is obtained. A rushed gear can be obtained.

In this embodiment, in the hydraulic control valve 11 with the torque transmitting direction changing means 12 described above, the valve body 21 is integrally connected to the steering handle of the gear body 41 in the steering shaft system 6. ing. With such a configuration,
Although it is often advantageous from the viewpoint of the on-board layout configuration, the present invention is not limited to such a structure. A gear body 41 constituting the torque transmission direction changing means 12 is provided on the steering handle side of the valve body 21 constituting the hydraulic control valve 11. They can also be connected together.

As shown in FIGS. 2 and 3, the hydraulic control valve 11 with the torque transmitting direction changing means 12 has the gear body 4 of the valve body 21 as described above.
The side 21b on one side is connected to the opening 41a of the gear body 41.
The two bodies 21 and 41 are integrally connected with each other in a state where the opening 41a is closed by engaging with the body. further,
As shown in FIGS. 2 and 3, a transmission shaft 23 integrally provided with a sleeve 25 constituting the rotary flow path switching valve 26 is inserted through the valve body 21 so that the gear body 4
In FIG. 1, the output shaft 43 extends so as to face the output shaft 43 from a direction in which the axis is substantially orthogonal to the output shaft 43.

The rear surface of the gear coupling bevel gear 50 which constitutes the torque transmission direction changing means provided at the extending end of the transmission shaft 23 and the end surface of the valve body 21 on the gear body 41 side are shown in FIG. And as shown in FIG.
Engaging portions 60 and 61 are provided to engage with each other in the axial direction. Note that the engaging portion 60 is a side surface on the side opposite to the meshing teeth of the bevel gear 50, and the engaging portion 61 is a bottom side surface of a recess formed in the end 21 b of the valve body 21.

According to the engaging portions 60 and 61, the bevel gear 5 can be easily pulled out of the hydraulic control valve 11 with the torque transmitting direction changing means 12 by disassembling the shaft.
0 can be removed. That is, the transmission shaft 23
The bevel gear 50, which is supported at the extended end thereof on the gear body 41 side of the valve body 21, has a large diameter.
It is necessary to assemble the valve assembly including the transmission shaft 23 and the like from the steering handle side and then from the opposite side. At this time, the bevel gear 50 needs to be supported on the transmission shaft 23 with no play in the rotational direction and the axial direction, and it is desired that the disassembling operation can be easily performed. 61 may be provided.

According to the above configuration, when the power steering device 1 is mounted on a vehicle, the hydraulic control valve 11 is conventionally connected integrally with the power steering main body 4 and thus has many restrictions on the space for mounting on the vehicle. Is formed as a separate member from the power steering main body 4, the space occupied around the steering link mechanism 3 between the left and right steering wheels 2, 2 can be reduced as much as possible.

Therefore, the power steering body 4 of the power steering apparatus 1 can be made much smaller than in the past, and can be relatively easily assembled into a vehicle. Also, when installing the hydraulic control valve 11 in a vehicle, the hydraulic control valve 11 that is relatively small compared to other parts can be installed using an appropriate empty space, so that it is easy to secure an installation space. Can be done
Easy to assemble. Further, the degree of freedom of the layout when the steering shaft system 6 is mounted on the vehicle can be provided.

The present invention is not limited to the structure described in the above embodiment, and the shape, structure, and the like of each part in the power steering device 1 can be appropriately modified or changed. For example, in the above-described embodiment, the case where the bevel gears 50 and 51 are used as the gear coupling means in the torque transmission direction changing means 12 has been described. However, the present invention is not limited to this, and a zero roll gear or the like may be used.

Further, in the above-described embodiment, the hydraulic control valve 11 is connected to the steering handle 5 side of the torque transmitting direction changing means 12 in the steering shaft system 6, but the present invention is not limited to this. Hydraulic control valve 1
1 may be connected to the steered wheel side of the torque transmission direction conversion means 12.

[0054]

As described above, according to the hydraulic control valve with the torque transmitting direction changing means according to the present invention, the valve body of the hydraulic control valve and the gear body of the torque transmitting direction changing means are integrally connected. These two bodies are used as lid members to close the openings of each other, can also be used as sealing parts, and the transmission shaft between them can be shared, so that the number of overall components is reduced, the size is reduced, and assembly is achieved. The operation can be simplified, and the torque can be reliably transmitted from the transmission shaft to the output shaft by a simple gear connection.

Further, according to the present invention, the torque transmission between the transmission shaft and the output shaft is performed by using a bevel gear or the like.
The transmission direction can be reliably changed in a direction substantially orthogonal to the transmission shaft, and the adjustment mechanism provided at the shaft end of the output shaft can perform adjustment to absorb backlash at the gear coupling portion.

Further, according to the present invention, such an adjusting mechanism is constituted by forming a back pressure chamber utilizing the tank pressure derived from the valve body side at the shaft end of the output shaft. Can be easily absorbed by automatic preloading, automatic backlash adjustment can be easily performed, gears can be connected without play, and machining and assembly errors can be absorbed.

Also, according to the present invention, the hydraulic oil on the hydraulic control valve side is introduced by guiding the tank pressure from the rotary flow path switching valve side as the hydraulic control valve into the gear body integrally connected to the valve body. Since it can be used as lubricating oil on the side of the torque transmission direction changing means, there is an advantage that the lubricating oil can be used in common and there is no need to newly add lubricating oil into the gear body. Further, since the lubricating oil is filled in the gear body of the torque transmission direction changing means, the gear coupling means can rotate smoothly, and the torque transmission and the transmission direction can be reliably changed.

According to the hydraulic control valve with torque transmitting direction changing means of the present invention, the torque transmitting direction changing means using a bevel gear or the like is coupled, so that the rotation is transmitted in a direction substantially orthogonal to the transmission shaft. The direction can be changed, and despite the simple structure, the mounting position of the hydraulic control valve can be selected and installed in locations where there is sufficient space, so that the assembly workability is also improved in terms of structure. Is also advantageous. In particular, such an advantage is effective when this kind of power steering device is incorporated in a vehicle having a space restriction such as a small passenger car.

Further, according to the present invention, since the hydraulic control valve with the torque transmitting direction changing means is separated from the power steering body having the steering gear and the power cylinder, the size of the power steering body can be reduced. Thus, the space occupied by the steering link mechanism between the left and right steering wheels can be made as small as possible, and the degree of freedom in the effective use of the mounting space in the vehicle and the layout configuration can be increased.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a power steering apparatus using a hydraulic control valve with a torque transmission direction changing means according to the present invention, and schematically showing the entirety thereof.

FIG. 2 is a longitudinal sectional view showing a hydraulic control valve with a torque transmission direction changing means according to the present invention.

FIG. 3 is an enlarged cross-sectional view of a main part of a hydraulic control valve with a torque transmission direction changing unit according to the present invention, in which a coupling portion between a valve body and a gear body is enlarged.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is a side view showing the appearance of FIG. 2;

FIG. 6 is a plan view of FIG. 5;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Power steering device, 2 ... Left and right steering wheels (front wheel), 3 ... Steering link mechanism, 4 ... Power steering main body part, 5 ... Steering handle, 6 ... Steering shaft system, 7 ... Rack shaft, 7a ... Rack, 8 ... Pinion, 9
... Rack and pinion type steering gear, 10 ... Power cylinder, 11 ... Hydraulic control valve, 12 ... Torque transmission direction changing means, 21 ... Valve body, 22 ... Input shaft, 23 ... Transmission shaft, 24 ... Rotor, 25 ... Sleeve, 26: rotary flow path switching valve, 27: torsion bar, 28, 29: bearing, 3
1 ... pump port, 32 ... tank port, 33, 34 ...
Output port, 35 ... bearing, 36 ... bearing, 37 ... plug member, 41 ... gear body, 42 ... gear cover, 43 ... output shaft, 44, 45 ... bearing, 46 ... adjustment mechanism, 47 ... back pressure chamber, 48 ... adjustment screw , 50, 51 ... bevel gear, 60,
61: engagement part, P: pump, T: tank, CL, CR ...
Left and right cylinder chambers.

Claims (3)

[Claims] 1. A steering gear section for steering left and right steering wheels via a steering link mechanism by a steering operation of a steering handle, and a power cylinder for applying a steering assist force to the steering link system by the steering operation. A power steering body, a hydraulic control valve for driving and controlling the power cylinder by a steering operation of the steering wheel, and a torque transmission provided in the middle of a steering shaft system for transmitting a steering operation state from the steering wheel to a steered wheel side. And a direction changing means, wherein the hydraulic control valve is formed separately from the power steering body, and a valve body of the hydraulic control valve is connected to a gear body of the torque transmitting direction changing means. The rotary shaft to the input shaft that rotates by steering operation. A transmission shaft connected via a valve extends through the valve body in the direction of the gear body, and faces the output shaft rotatably supported by the gear body from a direction substantially perpendicular to the axis. The transmission shaft and the output shaft are gear-coupled to each other by a gear coupling means in an internal space of the gear body, and the output shaft is axially movably supported in the gear body. A hydraulic control valve with a torque transmission direction changing means, comprising an adjusting mechanism capable of adjusting the amount of movement of the hydraulic control valve. 2. A steering gear unit for steering left and right steering wheels via a steering link mechanism by a steering operation of a steering wheel, and a power cylinder for applying a steering assist force to the steering link system by the steering operation. A power steering body, a hydraulic control valve for driving and controlling the power cylinder by a steering operation of the steering wheel, and a torque transmission provided in the middle of a steering shaft system for transmitting a steering operation state from the steering wheel to a steered wheel side. And a direction changing means, wherein the hydraulic control valve is formed separately from the power steering body, and a valve body of the hydraulic control valve is connected to a gear body of the torque transmitting direction changing means. The rotary shaft to the input shaft that rotates by steering operation. A transmission shaft connected via a valve extends through the valve body in the direction of the gear body, and faces the output shaft rotatably supported by the gear body from a direction substantially perpendicular to the axis. The transmission shaft and the output shaft are gear-coupled to each other in the internal space of the gear body by gear coupling means, and the rotation of the valve body is provided in the internal space of the gear body provided with the gear coupling means for the transmission shaft and the output shaft. A hydraulic control valve with torque transmission direction changing means, wherein a part of a return side flow path to a tank in a flow path switching valve is connected. 3. The hydraulic control valve with torque transmission direction changing means according to claim 2, wherein: a shaft end of the output shaft in the gear body opposite to a meshing portion of the output shaft with a gear on a transmission shaft side; A hydraulic pressure control valve with a torque transmission direction changing means, wherein a back pressure chamber communicated with an internal space connected to a return flow path to the tank is provided.