JP2565207Y2 - Rack and pinion hydraulic power steering system - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a rack and pinion type hydraulic power steering device supported on a vehicle body via an elastic body fitted into a housing.

[0002]

2. Description of the Related Art A rack and pinion type hydraulic power steering apparatus 100 shown in FIG. 12 has an input shaft 102 connected to a steering operation handle, a rack 103 meshing with a pinion 101 connected to the input shaft 102, and a rack 103. A housing 104 that covers the rack 103;
The steering wheel is connected through the connection 15. Thus, the steering wheel is steered by the movement of the rack 103 in the vehicle width direction due to the rotation of the input shaft 102.

[0003] Inside the housing 104 are formed oil chambers 106 and 107 partitioned by a piston 105. One end of pipes 108 and 109 for supplying pressure oil to the oil chambers 106 and 107 is fixed to the housing 104. ,
The other end is connected to the control valve 110. As a result, the oil chambers 106, 1
07 is supplied with pressurized oil, and an assisting force for the steering operation is applied to the rack 103.

[0004] Elastic bodies 111 and 112 are fitted around the outer periphery of the housing 104.
The housing 104 is supported by the vehicle body via the housing. This prevents the vibration transmitted from the road surface via the wheels from being transmitted to the vehicle body.

Further, telescopic covers 113 and 114 are provided, one end of which is fixed to the housing 104 and the other end of which is fixed to the tie rod 115 so as to be fixed to the rack 103. This prevents muddy water, dust, and the like from entering the inside of the housing 104.

[0006]

In the rack and pinion type hydraulic power steering apparatus 100 as described above, the mounting angle around the rack axis and the position in the rack axis direction with respect to the vehicle body are set to be constant. Therefore, the outer peripheral surface of one elastic body 111 is made non-circular, and the positioning of the housing 104 around the rack axis and the axial direction of the rack with respect to the vehicle body is performed with reference to the outer peripheral surface.

However, the elastic body 111 is not
The housing 1 at the time of fitting.
Even when the relative angle of the elastic body 111 with respect to the rack axis with respect to the rack axis and the relative position of the elastic body 111 in the rack axis direction are predetermined, the housing 104 and the elastic body 111 There is a possibility of relative rotation around the axis or relative movement in the rack axis direction. Then, the power steering device 1
00 cannot be mounted at a predetermined position with respect to the vehicle body.

Therefore, the elastic member 111 is formed by using a special jig.
Of the rack 104 relative to the housing 104 and the relative movement in the rack axis direction have been prevented. However, the special jig is the steering device 1
00 had to be removed when assembling it to the car body, which made the assembling troublesome.

One end of each of the elastic covers 113 and 114 is fixed by being fitted to the outer periphery of the housing 104. However, since the housing 104 is usually made of metal, the inner periphery of the elastic covers 113 and 114 and the housing 104 are fixed. However, there is a problem that the gap with the outer periphery is not enough and a gap is formed, and muddy water or the like enters through the gap. Therefore, the housing 10
The adhesion is improved by interposing an elastic body such as rubber between the outer periphery of the elastic member 4 and the inner periphery of the elastic covers 113 and 114. However, the number of parts increases and the assembly becomes troublesome. .

An object of the present invention is to solve the above-mentioned problems of the prior art.

[0011]

A feature of the present invention is that it comprises a pinion which is rotated by a steering operation input, a rack which meshes with the pinion, and a housing which covers the rack. Pressurized oil is supplied to the inside of the housing by piping fixed to the housing and supported by the vehicle body via the combined elastic body, and the pressure oil applies an assisting force for steering operation to the rack, and one end is connected to the housing. In a rack-and-pinion type hydraulic power steering apparatus provided with a telescopic cover made of an elastic material and fixed to a rack whose other end protrudes from the housing, a relative position of the elastic body and the housing around a rack axis is provided. The pipe is brought into contact with an elastic body so that rotation and relative movement in the axial direction of the rack can be prevented. Lies in one end of the over is fitted on the outer periphery of the elastic body.

[0012]

According to the structure of the present invention, the elastic body for supporting the housing on the vehicle body contacts the pipe fixed to the housing . Therefore, the relative movement of the relative rotation and the rack axial direction around the rack axis against the housing, housings
Occurs during transportation, etc. before attaching the
And a dedicated jig for preventing relative rotation and relative movement is not required.

By fitting one end of the elastic cover made of an elastic material to the outer periphery of the elastic body, the adhesion between the elastic cover and the housing is improved without increasing the number of parts.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

A rack and pinion type hydraulic power steering apparatus 1 shown in FIGS. 1 and 2 has an input shaft 2 connected to a steering wheel of a vehicle, a pinion 3 connected to the input shaft 2, and a rack meshing with the pinion 3. 4 and a housing 5 that covers the rack 4.

Tie rods 14 and 15 are connected to both ends of the rack 4 via ball joints 12 and 13,
Steering wheels (not shown) are connected via the tie rods 14 and 15. Thereby, the rotation of the input shaft 2 by the operation of the steering wheel is transmitted to the pinion 3, and the steering wheel is steered by the movement of the rack 4 in the vehicle width direction by the rotation of the pinion 3.

A pair of oil chambers 7, 8 partitioned by a piston 6 attached to the rack 4 are formed inside the housing 5 in order to provide an assisting force for the steering operation. Both ends of the oil chamber 7 are closed by seal members 9 and 10. A known control valve 11 is formed on the outer periphery of the input shaft 2 to supply hydraulic oil to the oil chambers 7 and 8 from a hydraulic pump (not shown) according to the steering resistance and the steering direction. The control valve 11 and the housing 5 are connected by two pipes 20 and 21, and one of the oil chambers 7
When pressure oil is supplied from one pipe 20 to the other, oil flows from the other oil chamber 8 through the other pipe 21 to a tank (not shown) via the control valve 11, and is returned to the other oil chamber 8. When pressure oil is supplied from the other pipe 21, the oil flows from one oil chamber 7 through one pipe 20 to the tank via the control valve 11.

In order to fix one of the pipes 20 to the housing 5 , as shown in FIG. 4, a cylindrical pipe joint 22 is welded to the housing 5 , and a step 22a formed inside the pipe joint 22 is formed. A flange 20a formed on the pipe 20
Are abutted via a seal ring 23, and a cylindrical male screw 24 is screwed into a female screw 22b formed on the inner periphery of the pipe joint 22, and the flange 20a is pressed against the step 22a by the male screw 24. Incidentally, the other pipe 21 is also fixed to the housing 5 in the same manner as one of the pipe 2 0.

In order to support the housing 5 on the vehicle body, rubber elastic bodies 30, 31 are fitted to one end and the center of the housing 5, respectively. The elastic bodies 30, 31 are shown in FIGS. Thus, the brackets 32 and 33 are covered by the brackets 32 and 33, and the brackets 32 and 33 are fixed to the vehicle body side member 34 by bolts 32a and 33a. At this time, the outer peripheral surface of the elastic body 30 at one end of the housing 5 is made non-circular and engages with the concave portion 34a of the vehicle body-side member 34. A mounting angle around the rack axis and a mounting position in the rack axis direction are determined.

The elastic body 30 at one end of the housing 5
Is brought into contact with one of the pipes 20, so that the elastic body 30
Relative rotation about the rack axis and relative movement of the housing 5 and the housing 5 in the rack axis direction are prevented. 5 to 7
As shown in FIG. 5, a concave portion 35 into which the bracket 32 is fitted is formed on the outer periphery of the elastic body 30, a plurality of circumferential grooves 36 are formed on the inner periphery for preventing relative sliding with the housing 5, and one end is formed at one end. Is formed with a semicircular notch 37. The outer peripheral surface of the pipe joint 22 of the pipe 20 contacts the inner peripheral surface of the semicircular notch 37. Thus, relative rotation of the elastic body 30 and the housing 5 around the axis of the rack 5
During the transportation before attaching to the vehicle body side member 34, etc.
Can be prevented from occurring . As shown in FIG. 1, a bush 38 that supports the rack 4 is inserted into one end of the housing 5, and the other end of the elastic body 30 abuts a flange 38 a that projects radially outward from the bush 38. . As a result, the elastic body 30 is sandwiched between the flange 38a of the bush 38 and the pipe joint 22 of the pipe 20, and the relative movement of the housing 5 in the rack axis direction causes the housing 5 to move to the vehicle body.
Occurs during transportation or the like before attachment to the side member 34
Can be prevented .

Each end of the housing 5 is covered with elastic covers 40 and 41 made of rubber bellows.
One end of each of the telescopic covers 40 and 41 is fixed to the housing 5, and the other end is fixed to the rack 4 by being attached to the tie rods 14 and 15 via clips 42 and 43.

A telescopic cover 40 covering one end of the housing 5
Is fitted on the outer periphery of the elastic body 30, and the retaining ring 45 is fitted on the outer periphery. Thereby, the elastic cover 4
Since the contact between the elastic member 30 and the elastic member 30 is made of elastic materials, the adhesion is improved, and the effect of preventing muddy water and dust from entering the housing 5 is improved. In addition, the elastic cover 4
One end of O is sandwiched between the step portion 30b on the outer periphery of the elastic body 30 and the flange 38a of the bush 38, thereby preventing the elastic member 30 from coming off.

According to the above configuration, the relative rotation of the elastic body 30 and the housing 5 around the rack axis and the relative movement in the rack axis direction can be controlled by the contact between the elastic body 30 and the pipe 20 .
Transportation process before attaching the housing 5 to the vehicle body side member 34
Since this can be prevented from occurring in the middle or the like, there is no need to use a dedicated jig for the prevention, so that the steering device 1 can be easily assembled to the vehicle body.

Further, since the elastic cover 40 is fitted to the elastic body 30, the sealing between the elastic cover 40 and the housing 5 is improved. Further, in this embodiment, the outer diameter of the elastic body 30 to which one of the elastic covers 40 is fitted is made equal to the outer diameter of the other end of the housing 5 to which the other elastic cover 41 is fitted. , 41 have the same shape.

The present invention is not limited to the above embodiment.

For example, in the above embodiment, the inner peripheral surface of the semicircular notch 37 formed at one end of the elastic body 30 is shown to be in contact with the outer peripheral surface of the pipe 20, but as shown in FIGS. Alternatively, a circular hole 37 'may be formed in the center of the elastic body 30, and the outer peripheral surface of the pipe 20 may be in contact with the inner peripheral surface of the hole 37'. In this case, the elastic body 30 has a hole 3 so that the pipe 20 can be inserted into the hole 37 '.
A split groove 39 extending from 7 ' to one end is formed. Further, one of the elastic covers 40 is fitted into a circumferential groove 48 formed on the outer periphery of the elastic body 30, whereby the elastic cover 40 is
From the elastic body 30 is prevented. Other parts are the same as those in the above embodiment, and the same parts are indicated by the same reference numerals. In the above embodiment, the rack is projected from both ends of the housing, and the present invention is applied to a steering device in which steering wheels are connected via tie rods connected to each end of the rack. The present invention can also be applied to a steering device which is protruded and has left and right steering wheels connected to the protruding portion via a rod.

[0027]

According to the rack and pinion type hydraulic power steering device of the present invention, the relative rotation of the elastic body and the housing around the rack axis and the relative movement of the rack in the axial direction are caused during the transportation before the housing is mounted on the vehicle body. etc
Can be prevented without using a special jig, and assembling to a vehicle body can be facilitated. Further, the sealing effect between the housing and the telescopic cover can be improved without increasing the number of parts.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a steering device according to an embodiment of the present invention.

FIG. 2 is a sectional view of the other side of the steering device according to the embodiment of the present invention.

FIG. 3 is a sectional view taken along line III-III of FIG. 1;

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

FIG. 5 is a plan view of the elastic body according to the embodiment of the present invention.

FIG. 6 is a front view of the elastic body according to the embodiment of the present invention.

FIG. 7 is a sectional view taken along line VII-VII of FIG. 6;

8 is a sectional view taken along line VIII-VIII in FIG.

FIG. 9 is a cross-sectional view of a steering device according to another embodiment.

FIG. 10 is a front view of an elastic body according to another embodiment.

11 is a sectional view taken along line XI-XI in FIG.

FIG. 12 is a sectional view of a steering device according to a conventional example.

[Explanation of symbols]

 4 Rack 5 Housing 20 Piping 30 Elastic body 40 Telescopic cover

Claims (1)

(57) [Scope of request for utility model registration] A first pinion that is rotated by a steering operation input; a rack that meshes with the pinion; and a housing that covers the rack. The housing is supported by a vehicle body via an elastic body fitted to the outer periphery. Pressure oil is supplied to the inside of the housing by piping fixed to the housing, and the pressure oil applies an assisting force for steering operation to the rack, and a rack having one end fixed to the housing and the other end protruding from the housing. In a rack-and-pinion type hydraulic power steering device provided with an elastic cover made of an elastic material fixed to the elastic member, relative rotation of the elastic body and the housing around the rack axis and relative movement in the rack axis direction are prevented. The elastic pipe is abutted on the elastic body so that one end of the elastic cover is fitted to the outer periphery of the elastic body. Rack and pinion hydraulic power steering system.