JPS58122257A - Power cylinder apparatus of vehicle - Google Patents

Abstract

PURPOSE:To eliminate the change in elastic pressing force due to a cylinder pressure by a constitution wherein a part for introducing the cylinder pressure is provided in an elastic pressing means for a pinion member for rear wheels which is provided in a power cylinder for front wheels. CONSTITUTION:A gear box 14 is provided with a steering shaft 13, which controls the lateral motion of a rack 17. A power cylinder 49 generates a steering supplemental power in a piston 17c by supplying chambers S1 and S2 with operation oil. In the chamber S1, a rack 17b and a pinion 19a are provided for steering rear wheels, and also an elastic pressing means 69 is provided. A support member 70 for the means 69 is provided with a communicating part 75 for making the pressure in a chamber S5 equal to that in the chamber S1. Therefore, elastic pressing force does not change when the operation oil is supplied to the chamber S1, and thus expected elastic pressing force can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power cylinder device mounted on a vehicle for reducing the steering torque 'ff applied to the steered wheels when steering wheels. A power cylinder capable of preventing the elastic force of an elastic pressure means for reliably meshing a rack part formed in a rack part with a pinion part of a pinion shaft from being affected by the hydraulic pressure of hydraulic oil supplied inside the power cylinder. Regarding equipment.

Many vehicles are equipped with power cylinders to reduce the steering torque that the driver needs to apply to the steered wheels when steering the front wheels, and to enable the front wheels to be steered using hydraulic auxiliary power. Equipped with Sarel. The piston front of the power cylinder slides linearly under the pressure of hydraulic oil supplied inside the power cylinder to assist in steering the front wheels.

By the way, a rack part is formed in the hydraulic oil supply chamber inside the power cylinder by the sliding movement of the piston rod, and the pinion part of the pinion shaft is engaged with the rack part, so that the piston rod can slide linearly. In some cases, the rotation of the pinion shaft made by the rotation of the pinion shaft is used to perform operations on the vehicle other than the front wheel steering operation. As an example of such an operation on a vehicle, there is a rear wheel steering operation using a steering device that can be used to steer the rear wheels together with the front wheels. .

In the steering device, the second pinion shaft constitutes a part of the path for transmitting the rear wheel steering force from the steered wheels to the rear wheel steering mechanism, and the rear wheels are steered by rotating the pinion shaft. Ru.

Hereinafter, in order to ensure that the piston rod and pinion portion of the power cylinder are engaged with each other, and to ensure that the sliding force of the piston rod is transmitted to the pinion shaft with the entire meshing force at a predetermined thickness, the power cylinder is equipped with an elastic means. is provided.

The pressing means includes a receiving part that receives the piston rod surface on the opposite side to the surface on which the rack part is formed, and an elastic part such as a spring arranged in a space on the back side of the receiving part. The elastic force of the elastic portion acts as an elastic force on the piston rod via the receiving member, causing the rack portion to mesh with the pinion portion with a predetermined meshing force.

As described above, the rack portion is formed on the piston rod so as to move in the hydraulic oil supply chamber, so the receiving member faces the hydraulic oil supply chamber. The hydraulic pressure of the hydraulic oil supplied to the hydraulic oil supply chamber acts on the outer periphery of the piston rod, but since the receiving member is in contact with a part of the piston rod, the piston is not in contact with the receiving part. The total hydraulic pressure acting on the surface of the rod, that is, the surface of the piston rod on which the rack portion is formed, is greater than the total hydraulic pressure acting on the surface of the piston rod that is in contact with the receiving member.

For this reason, the hydraulic joint difference reduces the elastic force of the elastic pressure means, and as a result, the meshing state between the rack part and the pinion part is affected. If there is, there may be cases where the expected adjustment force cannot be obtained.

The present invention includes a power cylinder used in a steering device that steers both front wheels and rear wheels by steering operation of a steering wheel, and includes a power cylinder that uses elastic pressure to obtain an engaging force between a rack portion of a piston rod and a pinion portion of a pinion shaft. This was accomplished in order to eliminate all of the above-mentioned problems regarding the elastic force in a power cylinder provided with the means.

An object of the present invention is to form a rack part in a power cylinder,
The power cylinder is provided with a pressure means that engages a pinion portion of a pinion shaft with the rack portion and applies a pressure force to a surface of the piston rod opposite to the rack portion, and the pressure means is formed inside the power cylinder. The structure includes at least a receiving member facing the hydraulic oil supply chamber and receiving the above-mentioned surface of the piston rod, and an elastic member such as a spring arranged in a space on the back side of the receiving member. All communication parts such as grooves and holes are formed to communicate the hydraulic oil supply chamber and the above space, so that the communication part allows the hydraulic oil in the hydraulic oil supply chamber to flow into the space, and the hydraulic pressure of the hydraulic oil is transferred to the space. It is made to act on the receiving member from the side as well, thereby making it possible to eliminate the total difference in hydraulic pressure acting on the piston rod, and making it possible to engage the rack part and the pinion part by a predetermined elastic force of the elastic pressure means. We provide power cylinder devices ffi for vehicles.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

Figure 1 is a plan view of a four-wheeled vehicle, showing the left and right front wheels 1.

1 is the shaft 2a. The left and right front wheel steering tie rods 3.3 are supported by a knuckle arm 2.2 that is rotatable left and right about the center of the 2affi, and whose outer ends are connected to the front wheel knuckle arms 2, 2. By moving the front wheel 1.1, the front wheel 1.1 is steered by the rotation of the knuckle arms 2, 2. The left and right rear wheels 4, 4 are also connected to the shaft 5 in the same way as the front wheels.
Knuckle arm 5 that can freely rotate left and right around a and 5a
, 5, and whose outer ends are connected to the rear wheel knuckle arms 5, 5, for left and right rear wheel steering;
6 moves in the left-right direction, the rear wheels 4, 4 are steered by rotation of the knuckle arm 5.5.

The front wheel knuckle arm 2 is suspended on the vehicle body by a front wheel suspension mechanism consisting of a lower arm 7, a shock absorber, etc., and the rear wheel knuckle arm 5 is also suspended on the vehicle body by a rear wheel suspension mechanism consisting of a lower arm 8, a shock absorber, etc. .

A steering side 110 is connected to the steering wheel 9 on which the driver performs a steering operation, and the steering shaft 10 consists of a main side 111, an intermediate 11+12, and an output 1 front 13 connected in series. As shown in FIG.
5.16 rotatably supported and output 1ill11
3 is integrally formed with a binion portion 13a. 1st
As shown in FIGS. 1 and 3, the gear box 14 has a long cylindrical shape that is long in the left and right direction of force, and a shaft 17 is slidably inserted inside the gear box 14, and each end of the shaft 17 protrudes from both ends of the gear box 14. The inner end portions of the front wheel steering tie rods 6, 3 are connected to the portions. As shown in FIG. 2, a rack portion 17a is formed on the shaft 17, and the binion portion 13a meshes with the rack portion 17a formed in the axial length direction of l'l1117.

Therefore, when the steering wheel 9 is rotated, the shaft 17 to which the steering torque is transmitted via the steering shaft 10 performs a left-right linear movement,
The front wheels 1.1 are steered by moving the tie rod 6.3 left and right. The second shaft 17 and the tie rod 3.6 constitute a front wheel steering mechanism 18 provided at the front of the vehicle.

A rack portion 17b separate from the rack portion 17a is formed on the through shaft 17 in FIG. 3, and a pinion portion 19a meshes with the rack portion 171). The pinion portion 19a is integrally formed at the front end of the connecting shaft 19 shown in FIG. 19 extends diagonally rearward and downward from the shaft 17. Through connection shaft 1 in Fig. 1
At the rear end of 9 is hydraulic oil 22 whose length direction is the longitudinal direction of the vehicle.
The front end of the rotating shaft 24' is connected to the rear end of the operating shaft 22 through a universal joint 25. From the hydraulic oil 22 as shown in Figure 6.
The pivot shaft 24 extending obliquely toward the rear is rotatably supported inside the gear box 26 by bearings 27 and 28. The operating shaft 22 is laid on the lower surface of the floor component of the vehicle so as to be exposed to the outside of the vehicle.In order to protect the operating shaft 22, a cylindrical cover member 29 is provided over substantially the entire length of the outer periphery of the operating shaft 22. are fitted.

The connecting shaft 19 is rotated by the horizontal linear movement of the shaft 17 by the steering operation of the steering wheel 9, and the rotation of the connecting shaft 19 is caused by the actuation shaft 22 rotatably supported by a bearing 30 inside the cover member 29. Since the signal is transmitted to the rotating shaft 24 via the steering wheel 9, the rotating shaft 24 rotates in conjunction with the steering wheel 9. When the rotation shaft 24 rotates, the rear wheel steering mechanism 31 operates to rotate the rear wheels 4.
, 4, the rotation shaft 24 serves as an input shaft for inputting the entire rear wheel steering force to the rear wheel steering mechanism 61.

Next, the structure of the rear wheel steering mechanism 61 will be explained.

As shown in FIG. 6, a pin 62 is connected to the rear end of the input shaft 24 protruding from the gear box 26 with an offset of eccentricity ``ε'' in the radial direction of the human power shaft 24, and the input shaft 24 and the eccentric pin 32 are The connection is made by connecting the block 63 fixed to the input shaft 24 and the block 64 holding the pin 32 fixedly with the spacer 3.
This is done by connecting with bolts 66 with 5 interposed. FIG. 8 shows a plan sectional view showing the structure behind the input shaft 24. One end of a connecting rod 67 is connected to the pin 62, and the tie rod connecting portion 39 is connected to the other end of the connecting rod 37 via a pin 68. are concatenated. The tie rod connecting member 39 is a member that connects the left and right rear wheel steering tie rods 6.6, and the tie rods 6.6 are connected to both ends of the connecting member 69.
The inner ends of the tie rod connecting members 39 are connected to each other, and the tie rod connecting members 39 are supported by bearings 42 and 43 of a holding frame 40.degree. 41 attached to the vehicle body, and are movable left and right.

The connection between the eccentric pin 62 and the connecting rod 37, the connection between the pin 38 and the quirod connection member 39, and the connection between the tie rod connection part 39 and the tie rod 6.6 are made using the pole joint 1.
- 44.45.46.46. Since the pin 32 is eccentric from the input shaft 24, the input shaft 24 and pin 62
The peripheral structure is a crank mechanism, and when the input shaft 24 rotates in conjunction with the steering wheel 9, the connecting rod 37 is caused to move horizontally by the eccentric pin 62 that rotates about the entire center of the input shaft 24, and the tie rod connecting member 39 moves left and right by the amount of the left and right movement component of the pin 62, thereby steering the rear wheels 4.4, and the rear wheel steering is performed together with the front wheel steering by the front wheel steering mechanism 18.

The eccentric pin 62, the connecting rod 37, the tie rod connecting member 69, the rear wheel steering tie rod 6, and the above constitute a rear wheel steering mechanism 61 provided at the rear of the vehicle.

When the steering wheel 9 is in the Nikotral rotation position, in other words, when the vehicle is traveling straight, the eccentric pin 6 is rotated as shown in Fig. 6.
2 is set to be located directly below the input shaft 24. When the rotation angle of the input shaft 24 is a small angle between 0° and 180°, and when the rotation angle is a large angle between 180° and 360°, the tie rod connecting part 39 changes the rotation angle of the input shaft 24. Reverse position when is 00 (because it is moving in the opposite direction to the left and right with respect to h,
In a small steering angle operation of the steered wheels 9 that rotates the input shaft 24 by a small angle, the rear wheels 4 are steered in the same direction as the front wheels 1, and in a large steering angle operation of the steered wheels 9 that rotates the input shaft 24 by a large angle. The rear wheels 4 can be steered in the opposite direction to the front wheels 1. Furthermore, if the rotation angle ratio between the steering wheel 9 and the input shaft 24 is set so that when the steering wheel 9 is operated by a large steering angle, the rotation angle of the input shaft 24 is 180° or around 180°. By large steering angle operation of the steering wheel 9, the rear wheel 40 steering angle is set to 08 or 0°.
You will be able to return to the vicinity.

As mentioned above, the steering torque applied to the steering wheels 9 is applied to the steering shaft 10 and the gear box 1'2I shown in FIG.
- Since the torque is transmitted to the front wheel steering mechanism 18 through the shaft 17, the steering wheel 9 and the front wheel steering mechanism 18 are connected through the steering torque transmission path 47 consisting of the steering shaft 10 and the shaft 17. Ru. Here, the shaft 17 is also a component of the front wheel steering mechanism 18 and a component of the steering torque transmission path 47.

The front wheel steering mechanism 18 and the rear wheel steering mechanism 31 are connected to the connecting shaft 1.
9, an operating shaft 22 and an input shaft 24, and a connection path 48 consisting of these coupling shafts, the operating shaft 22, and the input shaft 24 connects the front and rear wheel steering mechanisms 18.31. The steering torque transmission path 47 is a front wheel steering force transmission path from the steering wheel 9 to the front wheel steering mechanism 18, and the rear wheel steering force transmission path from the steering wheel 9 to the rear wheel steering mechanism 61 is Since it is constituted by the steering torque transmission path 47 and the connection path 48, the front wheel steering force transmission path and the rear wheel steering force transmission path overlap in the steering torque transmission path 47,
It has been made common. For this reason, the front wheel steering force transmission path and the rear wheel steering force transmission path are combined.

The route configuration can be simplified by removing the route component.

As shown in FIG. 3, the shaft 17 inserted into the gear box 14 is equipped with a piston portion 17C, and therefore, hydraulic oil supply chambers 81, 82 on the left and right sides of the piston are defined inside the gear box 14. 、Ru.

In this way, the gear box 14 is
The cylinder number 9 has a V-rule, and is the piston rod of the cylinder 49, which is the same as 41], 17, and the cylinder 49, and the power cylinder 49 has a nozzle for the front wheel. Since the rack portion 17b that engages with the piston rod shaft and the piny main portion 19a of the connecting shaft 19 is formed as shown in FIGS. 3 and 4, the rack portion 17b is formed as shown in FIGS. The disposed front wheel nozzle 49 is connected to the front part of the connecting path 48. On the other hand, the rear power cylinder 50 for the rear wheels is connected to the rear part of the connection path 48 as shown in FIG. 1, and the specific structure of the rear wheel cylinder 50 is shown in FIGS. 6 and 8. ing. The gear box 2
A pinion portion 24a is integrally formed on the input shaft 24 that is inserted through the input shaft 6, and the pinion portion 24a meshes with a rack portion 51a of a piston rod 51 whose axial direction is the left-right direction of the rear wheel nozzle cylinder 50. do. As a result, the rear wheel power cylinder 50, which is disposed at the rear of the vehicle like the rear wheel steering mechanism 31, is connected to the rear of the connection path 48 at the input shaft 24, which is the terminal shaft of the connection path 48. As shown in FIG. 8, the piston rod 51 is slidably inserted into the cylinder/hole 52, and the left and right hydraulic oil supply chambers 83.8 are provided with the piston portion 51b of the piston rod 51.
4 is formed as a section, and a cylinder nose (rel 52) is integrally connected to the gear box 26 with a bolt 53.

Left and right hydraulic oil supply chambers 81, 82, 83 of the power cylinders 49, 50 for the front and rear wheels. Steering wheel 9 to 84
A switching valve 54 for selectively supplying all hydraulic fluids depending on the steering direction of the vehicle is shown in FIG. The switching valve 54 is an open center type four-way switching valve, and the switching valve 54 is an open center type four-way switching valve.
It is integrally formed below the output i11+13 of O. A valve housing 55 housing the switching valve 54 is integrally connected to the gear box 14.

As shown in FIG. 1, the internal chamber of the valve housing 55 has an oil pump 56
It is connected to an oil tank 59 through a hydraulic pressure injection pipe 57 and a return hydraulic pressure pipe 58. Furthermore, the valve housing 5
The internal chamber 5 is connected to the left and right hydraulic oil supply chambers 81 and 82 by an oil passage formed in the wall of the cylinder 7Z of the gear box 14, that is, the power cylinder 49 for the front wheels. Hydraulic oil supply chamber S3. It is also connected to S4. Hydraulic oil from the oil tank 59 is supplied to the power cylinder 5 for the rear wheels.
These hydraulic lines 60,61 supplying
The piping is routed into the passenger compartment through the underside of the pipe, which protects it from mud and other negative effects on the passenger compartment.

As shown in FIG. 2, the teeth of the pinion part 13a of the output shaft 16 equipped with the switching valve 54 are helical teeth, and the rack part 17a of the piston rod 17 of the front wheel/pocket cylinder 50 that the pinion part 13a meshes with. The teeth are also helical teeth corresponding to this. However, when the steering torque due to the rotation of the steering wheel 9 is transmitted to the output 1hl1+13, a thrust in the axial direction is generated on the output shaft 13, which causes the switching valve 54 to rotate, albeit slightly. The switching valve 54 moves forward or backward depending on the direction in which the steering wheel 9 is steered, and the operating oil is switched by the switching valve 54. Hydraulic oil is selectively supplied to the hydraulic oil supply chamber via the hydraulic passage and the hydraulic pipe line. The switching operation principle of such a switching valve using helical teeth is the same as a known one.

The piston rod 17 of the front wheel power cylinder 49 supplied with hydraulic oil slides in the left and right direction by the hydraulic pressure acting on the piston portion 17C shown in FIG. The piston rod 51 of the rear wheel power cylinder 50, to which hydraulic oil is supplied, slides in the left-right direction by the hydraulic pressure acting on the piston portion 51b shown in FIG. Since the rotation of the input shaft 24 is achieved by adding the sliding force of the piston rod 51, the rear wheel steering operation is performed while receiving auxiliary power from the rear wheel power cylinder 50, so that the driver can steer the front wheels. The steering torque that must be applied to the steered wheels 9 to steer the rear wheels 1, 4 is reduced.

Here, it is possible to completely reduce the steering torque even if only one of the front wheel power cylinder 49 and the rear wheel power cylinder 50 is mounted on the vehicle, and one power cylinder is used for both the front and rear wheels. In this case, in order to transmit the auxiliary power of the power cylinder to both the front wheel steering mechanism 18 and the rear wheel steering mechanism 31, these mechanisms 18 and 31 are required.
It is necessary to increase the mechanical strength and rigidity by increasing the diameters of the connecting shaft 19, the operating shaft 22, and the input shaft 24, which are the path-constituting members of the connecting path 48 that connects. On the other hand, in this device, as mentioned above, the two power cylinders 49 and 50 for the front wheels and the rear wheels are connected to the front and rear of the connection path 48, so that the auxiliary power of the power cylinder 49 for the front wheels is used. The front wheel steering mechanism 18 includes a rear wheel power cylinder 50.
can directly transmit the auxiliary power to the rear wheel steering mechanism 61, and the connecting shaft 19, the operating shaft 22, and the input 11ui+24k
It has the advantage of being able to be made smaller in diameter.

As is clear from the above description, the present invention employs a rack and pinion mechanism for converting rotary motion into linear motion, or converting linear motion into rotary motion.

In order to reliably change the direction of motion and reliably transmit the wheel steering force, it is necessary to set the meshing depth between the rack and pinion parts to a predetermined depth and always maintain an appropriate meshing force. is necessary. For this reason, as shown in FIGS. 2, 3, 4, and 6, the pinions s13a, 19a
, 24a and the rack parts 17a, 17b, 51a that mesh with the rack parts 17a, 17b, 51a
Piston rod 17, 51 on the opposite side to the surface where
The spring force of springs 63, 64 and 65, which are elastic members, is applied to the surface.

The spring 66 shown in FIG. 2 constitutes a pressing means 68 together with a receiving member 66 and a reciprocating member 67. Four parts 6 inserted and formed on the front side
6a receives the piston rod 17 on the opposite side from the rack portion 17a. Advance/retract part A'A67 is a hexagonal head 67
8 on the outer end and a male threaded portion 671) formed on the outer circumferential surface, and is screwed into the female threaded portion 14C formed on the inner circumferential surface of the guide portion 141). .

When the advancing/retracting member 67 is screwed in the hexagonal head 67a, the spring force of the spring 63 interposed between the advancing/retracting member 67 and the receiving portion 4366 is increased or decreased by the forward or backward movement of the advancing/retracting portion restraint 67. , the above-mentioned pressing means 6 by the spring force
The rack portion 17 of the piston rod 17 with an elastic force of 8
a meshes with the pinion portion 13a of the output 11fb13.

The pressure means 69 shown in FIGS. 3 and 4 has the same structure as the pressure means 68 described above, and is slidably inserted into the cylindrical guide portion 14 (1) of the gear box 14.
) and (1- A short-shaft bolt shape that includes a receiving member 70 with a recess 70a formed on the upper surface for receiving the surface of the screw i/rond 17 on the opposite side, and a hexagonal head 71a' and is screwed into the guide part 14dK. The piston rod 17 is attached to the pinion portion 19a of the connecting shaft 19 by the forward/retractable portion 71 of
Rack part 17b'! An elastic force means 69 for elastic engagement is configured.

The pressing means 72 shown in FIG. 6 also includes a receiving member 73, a reciprocating member 74, and a spring 65.

As is clear from the following, the piston rod 17 of the front wheel power cylinder 49 is formed with different rack parts 173, 17b, and these rack parts 17a, 1
The output shaft 16, which is a separate pinion shaft, and the pinion portion 133.19a of the connecting shaft 19 are engaged with the output shaft 7b, and the respective engagement is performed by applying the elastic force of the elastic pressure means 68, 69.

If there are two engaging parts of the rack and pinion parts on the same shaft in this way, when the elastic force of one of the elastic means is adjusted, the piston rod 17 will move slightly due to flexural deformation in the elastic direction. Therefore, there is a possibility that the engagement state between the specific rack portion and the pinion portion by the other pressing means may be affected.

FIG. 5 shows the piston rod 171], the output shaft 16, and the pinion portion 13a of the connecting shaft 19.
．． It is a sectional view of piston rod 17 showing the meshing positional relationship with i9a. Pinion part 16a.

Since 19a is configured at an angle θ, the rack portion 17a.

17b is formed on the outer circumferential surface of the piston rod 17 over the entire angle θ. When the angle θ is 00 or 18o0, f'lJ is also the pinion part 13a. 19a or between the rack parts 17a, 171), one of the two pressure means 68, 69, for example the pressure means 6
8. Adjust the elastic force of rack part 17a and pinion part 1.
, 5a, the moving direction of the piston rod 17 due to elastic force adjustment is adjusted to the rack part 17.
I) and the meshing depth direction of the pinion part 19a match 1-7
Otherwise, a change will occur in the meshing state of the rack portion 17I) and the pinion portion 19a. In order to solve this problem, the rack parts 17a and 171], the pinion part ISa
and 198 form an angle, and the direction of movement of the piston rod 17 by adjusting the elastic force of the elastic force means 68 may be configured to be different from the direction of the depth of engagement between the rack portion 17b and the pinion portion 19a. Rack part 17a.

This problem is most effectively solved when the angle θ formed between pinion parts 17b and pinion parts 13a and 192 is 90°, and ideally it is preferable that the angle θ is 90°. It becomes practical even if the angle θ is set to an angle other than 08° and 180° due to constraints imposed on design such as placement.

As is clear from FIG. 3, the pinion portion 19 of the connecting shaft 19
a The pressure means 69 that engages the rack portion 17b of the Toviston rod 17 is provided in the left hydraulic oil supply chamber S1 of the front wheel power cylinder 49, and the receiving member 70 that constitutes the pressure means 69 is Facing the oil supply room S]. Moreover, the rack portion 17b is formed on the piston rod 17 so as to move in the hydraulic oil supply chamber S1, and the rack portion 17b is
The pinion part 1 is sandwiched between the piston rods 1' and 17 k.
It faces 9a. The hydraulic pressure of the hydraulic oil supplied to the chamber S1 acts on the outer periphery of the piston rod 17, but since the receiving member 70 is in contact with a part of the lower surface of the piston rod 17, The force of the hydraulic pressure acting on the upper surface is thicker than the force of the oil pressure acting on the lower surface of the piston rod 17, depending on the contact area between the piston rod 17 and the receiving member 70.The receiving member 70 is Since it is in close slidable contact with the inner peripheral surface of the cylindrical guide portion 14d, the space on the back side of the receiving portion 4A70 in which the spring 64 is accommodated, that is, the space between the receiving member 70 and the forward/backward lower part 1. S5 is isolated from the hydraulic oil supply chamber SI.For this reason, even if the advancing/retracting member 71 is fully screwed to increase/decrease the spring force of the spring 64 and adjust the elastic force of the elastic means 69, the piston will not move. Due to the existence of a difference in the dimensions of the rod 17 and the total hydraulic pressure on the lower surface, the predetermined elastic force *qrt may not be achieved.

Therefore, a communication groove part 73 is formed in the recessed part 70a of the receiving member 70 that contacts the piston rod 17, and the end thereof opens and faces the hydraulic oil supply chamber S1, and the communication groove part 73 and the space S5 are separated from each other. Connection is made via the communication hole portion 74. As a result, the hydraulic oil supply chamber S1 and the space S5 communicate with each other through a communication section 75 formed in the receiving member 70, which is composed of a communication groove section 76 and a communication hole section 74, and the hydraulic oil in the hydraulic oil supply chamber S1 flows into the space S5. do. As a result, the difference in hydraulic pressure between the upper and lower surfaces of the piston rod 17 is eliminated by the hydraulic pressure 1 acting on the receiving member 70 from the space S5 side, and the spring force of the spring 64 is transferred between the pinion portion 19a and the rack portion 17b. By using the 11 inch of the elastic force of the elastic means 690 to engage the elements, it is possible to achieve the desired effect.

As is clear from the above description, according to the present invention, the power cylinder is provided with an elastic pressure means that fully meshes with the rack part formed on the piston rod of the power cylinder and the pinion part formed on the pinion i11, Even if the receiving member constituting the compression means is placed in the hydraulic oil supply chamber of the power cylinder, the receiving member has a communication portion such as a groove or a hole that communicates the hydraulic oil supply chamber with the space on the back side of the receiving member. , it is possible to cause the hydraulic oil in the hydraulic oil supply chamber to flow into the space and apply hydraulic pressure to the receiving member from the space side. The total working oil pressure difference k jQ4 of the piston rod can be eliminated, and the rack part and pinion part can be brought into mesh with each other by the original elastic force of the elastic pressure means.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is an overall plan view of the vehicle, Fig. 2 is a side sectional view of the vicinity of the steering shaft and the power cylinder for the front wheels, and Fig. 3 is a part of the power 7 cylinder for the front wheels. 4 is a sectional view taken along the line 4-4 in FIG. 3, and FIG. 5 is a piston rod showing the positional relationship between the front wheel power/cylinder piston rod rack section and the pinion section that meshes with the rack section. FIG. 6 is a side sectional view of the vicinity of the input shaft connected to the rear wheel steering mechanism, and FIG. 7 is 7A-7A of FIG. 6. FIG. 8 is a composite half-cut view taken along the line 7B-7B, and is a plan sectional view of the vicinity of the rear wheel steering mechanism. In the drawings, 1 is a front wheel, 4 is a rear wheel, 9 is a steering wheel, 17 is a piston rod, 17b is a rack part, 18 is a front wheel steering mechanism, 19 is a connecting shaft which is a pinion shaft, 19a is a pinion part, 61 4 is a rear wheel steering mechanism, 47 is a steering torque transmission path, and 4 is a steering torque transmission path.
8 is a connection path, 49 is a front wheel power cylinder, 50 is a rear wheel power cylinder, 60.61 is a hydraulic pipe, 64 is a spring that is an elastic member, 69 is a pressure means, 70 is a receiving member, and 75 is a communication link. , S5 is a space. Patent applicant Honda Motor Co., Ltd. Patent attorney Yoshishita Shimoda Patent attorney Kunihiko Ohashi Figure 2

Claims (1)

[Claims] Forming a rack part on the piston rod of the power cylinder,
The power cylinder is provided with an elastic force that engages the rack with the pinion Hl of the pinion shaft and applies an elastic force to the surface of the piston rod opposite to the rack. The receiving member includes at least a receiving member facing the hydraulic oil supply chamber formed inside and receiving the surface of the piston rod, and an elastic member disposed in a space on the back side of the receiving member. A power cylinder device for a vehicle, characterized in that a communication portion such as a groove or a hole is formed so that the hydraulic oil supply chamber and the space are fully connected and allow oil in the hydraulic oil supply chamber to flow into the space.