JP2000296779A - Steering column support structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noises of a motor-driven power steering device, and to reduce the transmission of vibration to a car body from the steering column side by forming a structure of installing a car body installing bracket on the car body via an elastic body. SOLUTION: A bolt 8 is fastened between a car body installing bracket 4 and a car body 7 by a nut 9 via an elastic body 10 by insert molding. Thus, since a steering column is supported via the car body 7 and the eleastic body 10, the transmission of vibration can be reduced, and since support is the elastic body 10, installing dimensional accuracy of the car body installing bracket 4 can be relieved. At vehicle colliding time, the support elastic body 10 deflects in the shearing direction to relieve impact applied to a driver when the driver collides with a steering wheel 1. Since rigidity of a support part can be varied, a natural frequency can be adjusted, and for example, resonance in an unpleasant frequency can be avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering column support structure for mounting a steering column and a vehicle body in an electric power steering apparatus.

[0002]

2. Description of the Related Art FIG. 7 is a perspective view showing a conventional steering column support structure, FIG. 8 is a conceptual view of the same, FIG. 9 is an enlarged front view showing a vehicle body, in which 21 is a steering wheel, and 22 is a steering wheel. A steering shaft, 23 is a column case, 24 is a vehicle body mounting bracket, 25 is a nut, 26 is a bolt, 27 is a joint, 28 is a motor, and 29 is a vehicle body.

[0003]

Since the conventional steering column support structure is constructed as described above, the vehicle body side and the vehicle body mounting bracket are directly fastened by bolts, so that the motor and the steering wheel are rotated. There is a problem that vibration generated by each component is transmitted to the vehicle body and noise is easily generated. Conventionally, mini cars and 1
The electric power steering was applied to a relatively small displacement car of the 000cc class.
The required output of the motor also increases, and the operating noise also increases accordingly.

In general, a vehicle having a large displacement has a quiet cabin. In particular, when an electric power steering of a column assist type (a motor is disposed in the vehicle compartment) is adopted for a vehicle having a large displacement, noise is reduced. Reduction was required.

The present invention has been made to solve the above problems, and has as its object to reduce the noise of an electric power steering device and to reduce the transmission of vibration from a steering column to a vehicle body. I do.

[0006]

According to a first aspect of the present invention, there is provided a steering column support structure in which a vehicle body mounting bracket is mounted on a vehicle body via an elastic body.

According to a second aspect of the present invention, there is provided a steering column support structure in which an elastic body is made of rubber.

[0008] The steering column support structure according to claim 3 of the present invention has a rubber hardness of Hs60 or more.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a support structure of a steering column according to a first embodiment of the present invention, and FIG. 2 is an enlarged sectional view showing a vehicle body portion, where 1 is a steering wheel, 2 is a steering shaft, and 3 is a column. The case 4 is a bracket for attaching the vehicle body, 5 is a motor, 6 is a joint, 7 is a vehicle body, 8 is a bolt, 9 is a nut, and 10 is an elastic body. As shown in FIG. 2, a bolt 8 is fastened by a nut 9 between a bracket 4 for attaching the vehicle body and the vehicle body 7 via an elastic body 10 formed by insert molding.

With the above-described support structure,
By supporting the steering column via the vehicle body 7 and the elastic body 10, transmission of vibration can be reduced, and since the support is made of the elastic body 10, the dimensional accuracy of the mounting portion of the vehicle body mounting bracket 4 can be relaxed. Further, at the time of a vehicle collision, the support elastic body 10 bends in the shearing direction, so that the impact given to the driver when the driver collides with the steering wheel 1 can be reduced. Further, since the rigidity of the support portion can be changed, the natural frequency can be adjusted, and, for example, resonance in an unpleasant frequency range can be avoided. In addition, even at the time of reverse input on the tire side, the influence on the components can be reduced by the absorption of the elastic body 10.

As shown in FIG. 3, the elastic body 10 may be provided with a rib 10a. With this configuration, the noise reduction effect of the electric power steering device and the vibration transmission reduction effect from the steering column side to the vehicle body 7 can be further enhanced.

Further, as shown in FIG. 4, a structure in which the vehicle body mounting bracket 4 is embedded in the elastic body 10 may be adopted. Further, as shown in FIG. 5, a female screw may be provided on the vehicle body 7 side, and the whole may be tightened by bolts 11. Further, as shown in FIG. 6, a pair of elastic bodies 10 may be sandwiched above and below the vehicle body mounting bracket 4.

Embodiment 2 FIG. Elastic body 10 described in the first embodiment may be made of rubber. By using rubber in this manner, the structure can be simplified and the device can be manufactured at a lower cost.

Embodiment 3 In the above embodiment, the lower the rubber hardness is, the more the transmission of vibration can be reduced. However, if the hardness is low, the column is easy to move, and the steering feeling is deteriorated. Therefore, in order to achieve both, the rubber hardness can be Hs (Shore hardness) 60 or more.

[0015]

According to the steering column support structure according to the first aspect of the present invention, since the vehicle body mounting bracket is mounted on the vehicle body via the elastic body, the noise of the electric power steering device can be reduced. At the same time, vibration transmission from the steering column to the vehicle body can be reduced. In addition, it is possible to alleviate the accuracy of the components of the mounting portion and to alleviate the damage to the driver in the event of a vehicle collision.

Furthermore, by selecting the elastic force (hardness) of the elastic body, the adjustment of the natural frequency of the column and the steering feeling can be achieved at the same time, and the acting force on the components when a reverse input is generated from the tire side. Can be alleviated.
Also, if an elastic body is provided between the motor and the bracket, the backlash change of the worm gear meshing system of the motor will increase, and rattling noise generated from the gear meshing system will be easily generated. This is advantageous for the generation of rattle in the system.

According to the steering column support structure of the second aspect of the present invention, since the elastic body is made of rubber, the structure can be simplified and it can be manufactured at low cost.

According to the steering column support structure of the third aspect of the present invention, since the hardness of the rubber is set to Hs60 or more, it is possible to prevent the steering feeling from deteriorating and to reduce the transmission of vibration. .

[Brief description of the drawings]

FIG. 1 is a perspective view showing a steering column support structure according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a vehicle body according to Embodiment 1 of the present invention.

FIG. 3 is an enlarged sectional view showing a vehicle body part according to Embodiment 1 of the present invention.

FIG. 4 is an enlarged sectional view showing a vehicle body according to Embodiment 1 of the present invention.

FIG. 5 is an enlarged sectional view showing a vehicle body according to Embodiment 1 of the present invention.

FIG. 6 is an enlarged sectional view showing a vehicle body according to Embodiment 1 of the present invention.

FIG. 7 is a perspective view showing a conventional steering column support structure.

FIG. 8 is a conceptual diagram showing a conventional steering column support structure.

FIG. 9 is an enlarged sectional view showing a conventional vehicle body.

[Explanation of symbols]

4 Bracket for mounting on vehicle body, 7 Vehicle body, 10 elastic body.

 ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kyohei Yamamoto 2-6-1, Otemachi, Chiyoda-ku, Tokyo F-term (reference) in Mitsubishi Electric Engineering Co., Ltd. 3D030 DC02 DC16 DC17 DC22 3D033 CA02 3J048 AA01 BA03 BB10 EA21 3J066 AA04 BA01 BE10

Claims (3)

[Claims] 1. A support structure for mounting a steering column on a vehicle body, wherein a bracket for mounting the vehicle body is mounted on the vehicle body via an elastic body. 2. The steering column support structure according to claim 1, wherein the elastic body is made of rubber. 3. The steering column supporting structure according to claim 2, wherein the rubber has a hardness of Hs60 or more.