JP2002178936A - Mounting structure for steering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To resolve a problem that a high support load and a high vibration- proof property can not be obtained at the same time by a mounting structure for mounting a steering device for an automobile to a body frame therefor. SOLUTION: In this mounting structure 1 for the steering device 2, cylindrical elastic members 32 are fitted in insertion-holes 12 of the body frame 10, metal members 33 are inserted into the holes of the elastic members 32, and a hole is formed in each metal member 33. Each connection shaft 31 composed of a hexagon bolt is inserted into the through-hole 21 of the steering device 2 and the hole 51 of the metal member 33, and the male screw of the connection shaft 31 is driven into the female screw of a nut 70. The size of the elastic member 32 mounted to the body frame 10 having a marginal space can be increased, so that the maximum support load within an allowable stroke can be increased while using the soft elastic member having the excellent vibration- proof property.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure for mounting an automobile steering device to a vehicle body.

[0002]

2. Description of the Related Art In a conventional mounting structure for a steering device, for example, in order to block transmission of force or vibration received from wheels to a vehicle body, for example,
The steering device is elastically supported by the vehicle body. As usual,
The steering device is mounted on the vehicle body by fitting a rubber bush with a metal tube into a mounting hole formed in the mounting portion of the steering device, and screwing a fixing bolt that penetrates the metal tube into a frame of the vehicle body.

In some cases, the rubber bush described above has insufficient vibration damping properties. For example, in an electric power steering apparatus, high-frequency vibration due to rotation of a driving motor may occur in addition to vibration due to force received from wheels. However, when the above-mentioned rubber bush is used for this high-frequency vibration, the vibration-proof effect is small. In order to block the transmission of such vibrations to the cabin, it is required to improve the vibration proofness of the rubber bush.

[0004] However, since there is no space in the steering device which has a strong demand for miniaturization, only a small rubber bush can be used. If soft rubber is used in this small rubber bush having a small thickness of rubber in order to enhance vibration isolation, the rubber easily bottoms out even under a low load. That is, a required supporting load cannot be obtained within the elastic stroke range of the rubber.

If a hard rubber is used to solve this problem, on the contrary, the vibration-proofing property is deteriorated. Therefore, an object of the present invention is to solve the above-mentioned technical problems and to provide a mounting structure of a steering device capable of obtaining high vibration isolation and securing a high supporting load within an elastic stroke range. It is.

[0006]

According to the first aspect of the present invention, there is provided a connecting shaft fixed to a steering device, an insertion hole of a vehicle body frame through which the connecting shaft is inserted, and a holding shaft provided in the insertion hole. And the connecting shaft is inserted,
An attachment structure for a steering device, comprising: an elastic member that elastically supports a connecting shaft. According to the present invention, since the elastic member is accommodated in the insertion hole of the body frame having a sufficient space, a large elastic member can be used. Therefore, even if a soft elastic member having excellent vibration isolation is used, a high supporting load can be achieved within the allowable stroke of the elastic member (corresponding to the elastic range where the elastic member does not bottom out).

According to a second aspect of the present invention, in the mounting structure for a steering device according to the first aspect, the elastic member has a cylindrical shape, and a cylindrical metal member is provided between the elastic member and the connecting shaft. Provided is a mounting structure for a steering device, which is interposed. According to the present invention, since a general rubber bush with a metal cylinder can be used, it is possible to contribute to a reduction in the cost of the mounting structure. The invention according to claim 3 is the mounting structure for a steering device according to claim 1, further comprising tapered receiving surfaces formed on a pair of opening edges of the insertion hole, respectively, and formed in mutually opposite directions. The elastic member includes a pair of elastic members having a conical taper shape received by each receiving surface, has a truncated conical shape for pressing each elastic member against a corresponding receiving surface, and reduces the distance between each other via a connecting shaft. A mounting structure for a steering device, further comprising a pair of metal members provided.

According to the present invention, the pair of elastic members and the pair of metal members can be easily attached to the corresponding opening edges from opposite sides. Then, by a simple operation of reducing the distance between the metal members, the tapered elastic member is securely held in a pressed state in both the axial direction and the radial direction of the connecting shaft. Therefore, the mounting structure can be easily assembled.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A mounting structure of a steering device according to an embodiment of the present invention will be described below. FIG. 1 is an exploded perspective view of a mounting structure of a steering device according to a first embodiment of the present invention. FIG. 2 is a partial cross-sectional front view of the mounting structure shown in FIG. The mounting structure 1 includes a steering device 2
Is elastically supported by the body frame 10. The vehicle body frame 10 is, for example, a hollow cylindrical cross member extending in the width direction of the vehicle body. An attached portion 20 provided on the housing 6 is attached to the cross member. The steering device 2 is configured as a power steering device, and includes a rack-and-pinion type steering mechanism 3 and an assisting force applying mechanism 4 including an electric motor 7 and the like for applying a steering assisting force to the steering mechanism 3. ing. The steering device 2 includes a rack shaft 5 that is displaced in the axial direction for steering, a cylindrical housing 6 that accommodates and supports the rack shaft 5, and a housing 6.
And an electric motor 7 built therein to generate a steering assist force. The torque of the electric motor 7 is transmitted to the rack shaft 5 via a ball screw mechanism (not shown) or the like. The housing 6 extends in the width direction of the vehicle body, that is, the direction in which the axis of the rack shaft 5 extends, and the mounted portions 20 are provided at a plurality of positions, for example, at four positions. Each mounted portion 20 and the main mounting structure 1 related thereto are configured in substantially the same manner. Hereinafter, one mounting structure 1 will be described.

The mounting structure 1 includes a connecting shaft 31 fixed to the steering device 2, an insertion hole 12 of the vehicle body frame 10 through which the connecting shaft 31 is inserted, and a connecting shaft 31 held by the insertion hole 12 and connected to the connecting shaft 31. And an elastic member 32 which is inserted and elastically supports the connecting shaft 31. In particular, in the mounting structure 1 of the first embodiment of the present invention, the elastic member 32 has a cylindrical shape, and the cylindrical metal member 33 is interposed between the elastic member 32 and the connection shaft 31.

The elastic member 32 and the metal member 33 are
It constitutes an integral unit that functions as a bush. In this unit, the inner peripheral surface of the elastic member 32 and the outer peripheral surface of the metal member 33 are fixed by bonding or the like.
The method of fixing the elastic member 32 and the metal member 33 is not particularly limited. The outer peripheral surface of the elastic member 32 is fitted in the insertion hole 12 of the vehicle body frame 10. Body frame 10
Has a hollow rectangular tube shape having a substantially rectangular cross section. The vehicle body frame 10 includes a pair of opposed plate portions 13 that form one side facing each other having a rectangular cross section, a connection plate portion 14 that connects the pair of opposed plate portions 13, and an opening formed in each opposed plate portion 13. And a cylindrical portion 15 that connects the pair of opposing plate portions 13 at the peripheral edge. Each part of the body frame 10 is integrally formed. Insertion hole 1 inside cylindrical part 15
2 are sectioned. The cylindrical portion 15 is formed in a substantially cylindrical shape. The cylindrical portion 15 can reinforce the peripheral edge of the opening of the vehicle body frame 10 while receiving the load applied to the elastic member 32.

In the following, the direction in which the axis of the insertion hole 12 extends is also referred to as the axial direction. Further, a direction orthogonal to the axial direction is also referred to as a radial direction. The elastic member 32 is fitted into the insertion hole 12 in a press-fit state. The elastic member 32 has a cylindrical portion 42 that is cylindrical and is housed in the insertion hole 12.
And a pair of flanges 43 provided at both axial ends of the cylindrical portion 42 and extending radially outward. The cylindrical portion 42 and the pair of flanges 43 are integrally formed, and a hole 44 penetrating them is formed. The body frame 10 is interposed between the pair of flanges 43. One surface of each flange 43 facing each other is
Along the opposing plate portion 13 of the body frame 10 corresponding to this surface. Thereby, the elastic member 32 is positioned on the vehicle body along the axial direction.

The elastic member 32 is made of, for example, a material having an anti-vibration effect, such as natural rubber or synthetic rubber. The elastic member 32 has a predetermined thickness in the axial direction at the flange 43 and a predetermined thickness in the radial direction at the cylindrical portion 42. Here, the above-mentioned thickness is set to an amount which can obtain a sufficient vibration-proofing effect and can be elastically deformed when an assumed maximum load is applied. The metal member 33 passes through the hole 44 of the elastic member 32. The metal member 33 is made of, for example, a hard member such as steel or an aluminum alloy. The metal member 33 has a hole 5 through which the connecting shaft 31 passes.
One.

The connecting shaft 31 is made of, for example, a general-purpose hexagonal bolt. This bolt has a head portion 61 at one end and a shaft portion 62 on which a male screw is formed. The male screw is inserted through the through hole 21 and the hole 51 of the metal member 33, and the nut 70
It is screwed into the female screw formed in the. The mounting portion 20 of the steering device 2 has a through hole 21 through which the shaft portion 62 of the connection shaft 31 is inserted. The through-hole 21
Are formed on the housing 6 and the housing 6
It may be formed separately from and formed on a member fixed to the housing 6.

In the mounting structure 1, the head 61 of the connecting shaft 31
Is supported by the peripheral portion of the through hole 21, and the shaft portion 62 passes through the through hole 21, and the male screw of the connection shaft 31 is screwed into the female screw of the nut 70. In this state, the steering device 2, the connection shaft 31, the metal member 33, and the nut 70 are rigidly connected, and the metal member 33 and the vehicle body frame 10 are connected via the elastic member 32. Thus, the steering device 2 is elastically supported in all directions via the elastic member 32.

The body frame 10 is connected to the connecting shaft 31.
The manner of connection between the housing and the housing 6 is not limited to the above. For example, a female screw into which the male screw of the connection shaft 31 is screwed is formed in the through hole 21 of the housing 6 instead of the nut 70, and the metal member 33 is provided between the head 61 of the connection shaft 31 and the mounting portion 20 of the housing 6. May be interposed and fixed. In addition, the above-described elastic member 32 is press-fitted into the insertion hole 12 of the body frame 10, but is not limited thereto. For example, instead of press-fitting, the elastic member 32 may be fixed to the cylindrical portion 15 in the insertion hole 12 by adhesion.
Further, press-fitting and bonding may be used in combination. The elastic member 32 may be formed integrally with the insertion hole 12 of the body frame 10.

When assembling the above-described elastic member 32 to the vehicle body frame 10, as in the second embodiment,
Pressing and bonding can be avoided. In short, the elastic member 32 only needs to be held in the insertion hole 12 of the vehicle body frame 10. The second embodiment is different from the first embodiment in the following points, and the other points are configured in the same manner, and the same reference numerals are given and the description is omitted. FIG. 3 is a partial cross-sectional front view of the mounting structure according to the second embodiment of the present invention.

In the mounting structure 1 according to the second embodiment, the body frame 10 is formed with a pair of opening edges 16 of the insertion holes 12 which are both ends of the cylindrical portion 15 and has tapered shapes opposite to each other. Are provided.
In addition, the elastic member 32 includes a pair of elastic members 34 having a conical taper shape received by each receiving surface 17.
Correspondingly, the metal member 33 includes a pair of metal members 35 and 36, and the pair of metal members 35 and 36 has a truncated cone shape, and the distance between the metal members 33 and 36 can be reduced via the connection shaft 31. This allows each elastic member 34 to correspond to the corresponding receiving surface 17.
, Respectively.

The insertion hole 12 of the body frame 10 is defined by a pair of receiving surfaces 17 each forming a substantially conical surface, and a cylindrical surface 18 connecting the small diameter side edges of the pair of receiving surfaces 17. The receiving surface 17 forms a tapered surface having a predetermined inclination angle with respect to the axis of the insertion hole 12, and the inclination angle of each receiving surface 17 is:
Have been equal. The pair of elastic members 34 are substantially cup-shaped and have the same shape. Each elastic member 34 has a hole 44 through which the connecting shaft 31 passes near the top of the conical shape, and a contact surface 46 on the outer peripheral surface forming a conical surface. This contact surface 4
6 is in contact with the receiving surface 17 of the insertion hole 12. Also,
Each elastic member 34 has a predetermined thickness in an axial direction and a radial direction between an inner peripheral surface and an outer peripheral surface forming a conical surface. These thicknesses are set to such an amount that a sufficient vibration-proofing action can be obtained and the elastic deformation is possible when the assumed maximum load is applied. On the inner peripheral surface, a metal member 33
Are fixed, and each elastic member 34 and each metal member 35, 36 are fixed.
“Constitutes a unit that functions as a bush.

The pair of metal members 35 and 36 has a conical outer peripheral surface adhered to the inner peripheral surface of each elastic member 34,
Each has an end surface serving as a bottom surface of the truncated cone, and is formed in substantially the same shape. The hole 51 of one metal member 35 has a cylindrical surface through which the connecting shaft 31 is inserted. The hole 51 of the other metal member 36 is formed with a female screw into which a male screw of the connection shaft 31 is screwed. The connection shaft 31 is screwed into the metal member 36 through the housing 6 and the metal member 35. By tightening the male screw of the connecting shaft 31 into the female screw of the metal member 36, a pair of metal members 35, 36
Can be brought closer to each other.

In the mounting structure 1 of the present embodiment, the distance between the pair of metal members 35, 36 is a predetermined distance, and in this state, each elastic member 34 Are pressed in substantially the same state in both the axial direction and the radial direction in a pressed state. Thus, the steering device 2 is elastically supported via the pair of elastic members 34 while obtaining substantially the same vibration isolation in all directions. As described above, according to each embodiment of the present invention, the elastic member 32 is accommodated in the insertion hole 12 of the vehicle body frame 10 having a sufficient space, so that a large-sized elastic member 32 can be used. Therefore, even if a soft elastic member 32 having excellent vibration proof properties is used, a high supporting load can be achieved within the allowable stroke of the elastic member 32 (corresponding to the elastic stroke range where the elastic member does not bottom).

Further, in the mounting structure 1 of the first embodiment,
It has a cylindrical elastic member 32 and a cylindrical metal member 33 between the elastic member 32 and the connecting shaft 31. These include
As a rubber bush with a general metal cylinder can be used,
This can contribute to a reduction in the cost of the mounting structure 1. Further, in the second embodiment, by reducing the distance between the pair of metal members 35 and 36 having a truncated conical shape, the pair of elastic members 34 having a conical taper shape can be connected to the tapered receiving members having opposite directions. The surface 17 was pressed. Thereby, the actual mounting structure 1 can be easily assembled. That is, the pair of elastic members 34 and the pair of metal members 3
5 and 36 can be easily attached to the corresponding opening edges 16 from opposite sides. Then, for example, by a simple operation of tightening a bolt to reduce the distance between the pair of metal members 35 and 36, each of the tapered elastic members 3 is formed.
4 can be reliably held in a pressed state in both the axial direction and the radial direction.

In the second embodiment, a pair of elastic members 34 are collectively attached to the corresponding receiving surface 17 with the tightening of a bolt which is a connecting shaft 31 for fixing the steering device 2 and the metal member 33. Pressing is performed. Further, thereby, the mounting of the pair of elastic members 34 to the insertion holes 12 and the mounting of the steering device 2 to the vehicle body frame 10 can be simultaneously performed simultaneously. Also, the elastic member 32
The metal member 33 is accommodated in an internal space of the body frame 10 that is not normally used, and the mounted portion 20 of the steering device 2 can be made smaller than a conventional structure in which a rubber bush is mounted in a hole of the steering device. . Thus, despite the use of the large elastic member 32, the mounting structure 1 can be prevented from increasing in size, and can be further reduced in size.

According to the mounting structure 1, the steering device 2 can be mounted on the vehicle body frame 10 without rattling. Further, the large-sized elastic member 32 can suppress transmission of low-frequency vibration from the wheels and high-frequency vibration from the electric motor 7 to the vehicle interior. In addition, the above-described insertion hole 12 is formed in the hollow cross member as the vehicle body frame 10, but is not limited thereto.
For example, the body frame 10 may be a member having a C-shaped cross section, or may be a part of a so-called monocoque body type body in which the frame and the body shell are integrally formed by welding or the like. It may be a member rigidly connected to such a vehicle body or a frame. In short, it is only necessary that the vehicle body frame 10 be provided with the insertion hole 12 that can hold the inserted elastic member 32.

The present invention also relates to an electric type having an electric motor 7 for generating a steering assist force, in particular, a type in which the electric motor 7 is fixed to the housing 6, and a rotation of the electric motor 7. This is preferable for a power steering device of a type in which force is transmitted to the rack shaft 5 via a ball screw mechanism as a speed reduction mechanism. This is because, in each type of power steering device described above, in addition to the relatively low frequency vibration caused by the force received from the wheels, the relatively high frequency vibration caused by the rotation of the electric motor 7 and the operation of the reduction mechanism. Vibration tends to occur easily. In a conventional mounting structure that can only use a small elastic member, it is difficult to obtain a vibration-proof property against high-frequency vibration at a practically sufficient level while obtaining a high supporting load. This is because the mounting structure 1 can suppress high-frequency vibrations as well as low-frequency vibrations at a high level while obtaining a high supporting load.

Further, the present invention may be applied to a manually operated steering device 2 which cannot obtain a steering assist force, in addition to the power steering device. The configuration of the steering mechanism 3 can use other known configurations in addition to the rack and pinion type described above. In addition, various design changes can be made without changing the gist of the present invention.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a mounting structure of a steering device according to a first embodiment of the present invention, in which a steering device and a body frame are also illustrated.

FIG. 2 is a partial cross-sectional front view of the mounting structure shown in FIG.

FIG. 3 is a partial cross-sectional front view of a mounting structure of a steering device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mounting structure 2 Steering device 10 Body frame 12 Insertion hole of body frame 16 Opening edge 17 Receiving surface 31 Connecting shaft 32 Elastic member 33 Metal member 34 A pair of elastic members 35, 36 A pair of metal members

Claims (3)

[Claims] 1. A connecting shaft fixed to a steering device, an insertion hole of a vehicle body frame through which the connecting shaft is inserted, and an elastic member held in the insertion hole and through which the connecting shaft is inserted to elastically support the connecting shaft. And a mounting structure for a steering device. 2. The mounting structure for a steering device according to claim 1, wherein the elastic member has a cylindrical shape, and a cylindrical metal member is interposed between the elastic member and the connection shaft. Mounting structure for steering device. 3. The mounting structure for a steering device according to claim 1, further comprising tapered receiving surfaces formed on a pair of opening edges of the insertion hole, respectively, and formed in opposite directions. A pair of metal members including a pair of elastic members having a conical taper shape received by each receiving surface, forming a truncated cone shape for pressing each elastic member against a corresponding receiving surface, and reducing a distance between each other via a connecting shaft. A mounting structure for a steering device, further comprising a member.