JP2003040114A - Tilting structure for electric power steering - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tilting structure for an electric power steering having a tilt turning shaft arranged between an electric power steering motor and a steering wheel for reducing the load of a steering column during tilting operation. SOLUTION: The tilt turning shaft 10 as a connection between a reduction gear cover 7 and a lower bracket 3 is arranged on the rear side of a vehicle beyond the electric power steering motor 8 fixed to the reduction gear box 6, on the front side of the vehicle beyond the steering wheel 4. During tilting operation of the steering column 1, the electric power steering motor 8 located on the front side of the vehicle beyond the tilt turning shaft 10 serves as a balancer for the steering wheel 4 and so the steering column 1 with the steering wheel 4 can be tilted with a small load.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilt structure for an electric power steering system that reduces a load during tilt operation of a steering column.

[0002]

2. Description of the Related Art Conventionally, a power steering structure for an automobile employs a structure for supporting a rotational operation force of a steering wheel by using a pneumatic type, a hydraulic type, an electric type or the like as a power source. The structure used was the mainstream. 2. Description of the Related Art In recent years, development of electric power steering using an electric power steering motor as a power source has been promoted and adopted because of suppression of drive loss of an engine and installation in a vehicle.

As shown in FIG. 6, a conventional electric power steering system includes a steering column 1 and a steering wheel 4 equipped with an airbag at an end of the steering column 1 on the rear side of the vehicle. Is equipped with a reduction gear box 55 and a reduction gear cover 56,
The reduction gear cover 56 is arranged on the front side of the vehicle with respect to the reduction gear box 55.
It is fixed at 7. An electric power steering motor 8 is fixedly installed on the side surface of the reduction gear box 55.
Further, the steering column 1 is fixed to a vehicle body member 54 via vehicle body side brackets 52, 53 on the vehicle front side and the vehicle rear side, and the vehicle body side on the vehicle front side. A tilt rotation shaft 50 of the tilt mechanism is fixedly provided at a portion where the bracket 52 and the reduction gear cover 56 are connected. This part serves as a fulcrum when the steering column 1 equipped with the steering wheel 4 is tilted. Further, a tilt lever 51 used when locking or unlocking the steering column 1 at a predetermined position is fixed to a vehicle body side bracket 53 on the vehicle rear side.

The conventional electric power steering system employs a tilt mechanism so that the driver can voluntarily adjust the position of the steering wheel 4 in accordance with the physique and driving posture of the driver. This tilt mechanism
It is a mechanism that allows the steering wheel 4 to be adjusted in the vertical direction, and includes a tilt rotation shaft 50 that allows the steering column 1 to swing and a tilt lever 51 that fixes the steering column 1 at a predetermined position. Then, by operating the steering wheel 4 up and down, the tilt rotation shaft 5
The steering column 1 is swung to a predetermined position with 0 as a fulcrum, and the tilt lever 51 is attached to the tilt lever shaft center portion 51.
The steering column 1 is fixed by rotating in a counterclockwise direction locking around a. Here, the tilt rotation shaft 50 has a layout in which it is located further to the vehicle front side than the steering wheel 4 and the electric power steering motor 8 together with the vehicle body side bracket 52 on the vehicle front side.

[0005]

As described above, the conventional electric power steering is considerably heavy because the steering wheel is provided with the airbag and the electric power steering motor is provided.
Further, since the tilt rotation shaft is disposed on the front side of the vehicle with respect to the steering wheel and the electric power steering motor, the load acting on the steering wheel at the time of tilt operation is the weight of both the steering wheel and the electric power steering motor. Therefore, the tilt operation becomes difficult. Therefore, in the conventional electric power steering, a balance spring was mounted on the steering column to exert a spring force in a direction to urge the steering wheel upward, but this spring force causes the steering wheel to be released when the tilt lever is released during tilt operation. The column bounces up,
It is difficult to adjust the steering column to a predetermined tilt position.

In the electric power steering device disclosed in Japanese Patent Laid-Open No. 2000-38146, as shown in FIG. 1, the tilt rotation shaft is located on the front side of the vehicle with respect to the steering wheel and the electric motor. No consideration was given to the load on the tilt operation of the column. The present invention has been made in view of the above point, and an electric power steering system in which a tilt rotation shaft of a steering column is disposed between an electric power steering motor and a steering wheel to reduce a load during a tilt operation. It is an object of the present invention to provide a tilt structure.

[0007]

As a means for solving the above problems, the present invention as set forth in claim 1 is as follows.
In a tilt structure of an electric power steering, a steering wheel is provided at one end of a steering column, an electric power steering motor is provided at the other end, and a tilt rotation shaft serving as a fulcrum when tilting the steering column is provided. The tilt rotation shaft is arranged between the electric power steering motor and the steering wheel. With this configuration, since the tilt rotation shaft that serves as a fulcrum during tilt operation of the steering column is disposed between the steering wheel and the electric power steering motor, the load during tilt operation of the steering column is It operates with the tilt rotation axis as a fulcrum, but since the electric power steering motor acts as a balancer for the steering wheel, these weights are hardly transmitted to the steering wheel, and tilt operation is easily performed. be able to.

According to a second aspect of the present invention, in the first aspect of the present invention, the tilt rotation shaft is provided on a vehicle body side bracket disposed on a vehicle rear side of the electric power steering motor. It is characterized by With this structure, the tilt rotation shaft is provided on the rigid vehicle body side bracket disposed on the rear side of the vehicle from the electric power steering motor, and therefore acts on the tilt rotation shaft that serves as a fulcrum during tilt operation. It can fully support the load.

A third aspect of the invention is characterized in that, in the first or second aspect of the invention, the electric power steering motor is disposed below a center line of the steering column. With this configuration, the electric power steering motor is arranged below the center line of the steering column. Therefore, when assembling the electric power steering motor, etc., the electric power steering motor is not close to the peripheral members, so wiring etc. Can be easily assembled.

The invention described in claim 4 is the same as claims 1 to 3.
In the invention described in any one of above, the electric power steering motor is arranged between an extension line of an outer peripheral edge portion of a steering column cover covering the steering column and a center line of the steering column. To do. With this configuration, the electric power steering motor is disposed inward of the extension line of the outer peripheral edge of the steering column cover that covers the steering column, so that the layout of peripheral components is not hindered. Moreover, the electric power steering motor does not hinder an occupant during driving.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a tilt structure of an electric power steering according to an embodiment of the present invention will be described in detail with reference to FIGS. In the description of the embodiments of the present invention, the same members as those in the conventional example will be described using the same reference numerals. As shown in FIG. 1, the steering column 1
Is an upper bracket 2 located on the vehicle rear side and fixed to the lower surface of a steering column hanger 31 fixed to a substantially columnar steering support member 30 mounted on the vehicle body side frame in the vehicle width direction. It is installed so as to be tiltable in the vehicle interior via the lower bracket 3 located. Further, the steering column 1 connects the upper steering shaft 1a, the middle steering shaft 1b (see FIG. 2) and the input steering shaft 1c, and the upper steering shaft 1a
A steering wheel 4 is attached to the rear end of the vehicle. The upper steering shaft 1a and the middle steering shaft 1b are rotatably arranged on the upper bracket 2 via an outer jacket 1d and an inner jacket 1e. The inner jacket 1e is stretchably held in the outer jacket 1d. The upper bracket 2 has an upper steering shaft 1
A shaft center portion 5a is provided below the center line of a, and the tilt lever 5 formed in a substantially L shape can be rotated about the shaft center portion 5a as a fulcrum. Also the upper bracket 2
A mounting bracket 2a, which is formed in a substantially rectangular shape and is fixed to the steering column hanger 31, is mounted on the upper part of the mounting bracket 2a. ing.

Further, as shown in FIGS. 2 and 3, in the shaft center portion 5a of the tilt lever 5, a slightly inclined long hole 5c penetrating the upper bracket 2 in the vehicle width direction is formed.
A lock bolt 5d fixed to the tilt lever 5 is inserted into the long hole 5c. The steering column 1 can be fixed to the upper bracket 2 by rotating the lock bolt 5d integrated with the tilt lever 5 counterclockwise, and the steering column 1 can be fixed by rotating the lock bolt 5d clockwise. It can be canceled from. The steering column 1 is swingable within the range of the length w of the long hole 5c of the upper bracket 2. The upper bracket 2 is fixed to the lower surface of the steering column hanger 31 by the mounting bolts 32 via the mounting brackets 2a.

As shown in FIGS. 4 and 5 (see also FIG. 1), the reduction gear box 6 located on the front side of the vehicle and the reduction gear cover 7 located on the rear side of the vehicle are attached to the mounting bolt 3.
3, the input steering shaft 1c is rotatably supported in the reduction gear box 6 and the reduction gear cover 7. Further, an electric power steering motor 8 having a substantially cylindrical shape is attached to one side surface of the reduction gear box 6 so as to be positioned below the center line of the steering column 1. Further, a lower steering shaft 35 is connected to an end portion of the input steering shaft 1c on the vehicle front side via a universal joint 34.

The reduction gear cover 7 is connected to the lower bracket 3 on the vehicle rear side of the electric power steering motor 8 and above the center line of the steering column 1. The lower bracket 3 is formed in a substantially U-shape that opens downward so as to sandwich the upper side of the reduction gear cover 7, and is also a mounting flange 3b that is mounted on the steering column hanger 31.
And an insertion hole 3a through which the shaft 9 is inserted. The reduction gear cover 7 also has an insertion hole 7a through which the shaft 9 is inserted. Then, the lower bracket 3 sandwiches the upper side of the reduction gear cover 7, and the shaft 9 is inserted into the insertion hole 3a of the lower bracket 3 and the insertion hole 7a of the reduction gear cover 7,
The reduction gear cover 7 is rotatably connected to the lower bracket 3. This connecting part is the steering column 1.
The tilt rotation shaft 10 serves as a fulcrum when the tilt operation is performed.
Further, the mounting bracket 3b of the lower bracket 3 is formed with an insertion hole 3d having an open end through which a mounting bolt 36 for mounting the lower bracket 3 on the lower surface of the steering column hanger 31 is inserted.

Next, a tilt operation of the electric power steering according to the embodiment of the present invention will be described. Figure 1
As shown in FIG. 2, when the tilt lever 5 provided on the upper bracket 2 is rotated clockwise around the shaft center portion 5a as a fulcrum to the position shown by the dotted line, the steering column 1 is tilted. It becomes possible to swing in the vertical direction with 10 as a fulcrum, and when the steering column 1 is arranged at a predetermined tilt position, the tilt lever 5 is rotated counterclockwise to the position shown by the solid line with the shaft center portion 5a as a fulcrum. Then, the steering column 1 can be fixed.

According to the embodiment of the present invention, as shown in FIG. 1, the position of the tilt rotation shaft 10 is indicated by an alternate long and short dash line from the position of the conventional tilt rotation shaft 50 (see FIG. 6) in the direction of the arrow. When the tilting operation of the steering column 1 is performed, the steering column 1 is moved to the rear of the vehicle and is disposed on the vehicle rear side of the electric power steering motor 8 fixed to the reduction gear box 6 and on the vehicle front side of the steering wheel 4. The electric power steering motor 8 located on the vehicle front side of the tilt rotation shaft 10 serves as a balancer for the steering wheel 4, and the steering column 1 including the steering wheel 4 can be operated up and down with a small load.

The electric power steering motor 8
Is fixed to the side surface of the reduction gear box 6 below the center line of the steering column 1. Further, a steering column cover 11 is provided around the steering column 1 in the vicinity of the steering wheel 4 so as to cover the steering column 1, and the electric power steering motor 8 is provided below the steering column cover 11. Since it is arranged between the center line of the steering column 1 and the inside of the extension line of the outer peripheral portion of the substantially semi-cylindrical shape, a wide space is secured between the electric power steering motor 8 and the peripheral members. be able to.

[0018]

As described above, according to the first aspect of the present invention, the tilt rotation shaft serving as a fulcrum when the steering column is tilted is disposed between the steering wheel and the electric power steering motor. Therefore, the load at the time of tilting the steering column acts with the tilt rotation axis as the fulcrum, but since the electric power steering motor acts as a balancer for the steering wheel, these weights are not applied to the steering wheel. Since there is almost no transmission, the driver can easily tilt the steering wheel to the desired position. Further, the balance spring, which was required as a separate component in the past, is not required, and the cost can be reduced.

According to the second aspect of the invention, since the tilt rotation shaft is provided on the rigid vehicle body side bracket disposed on the vehicle rear side of the electric power steering motor, it serves as a fulcrum during tilt operation. The load acting on the tilt rotation shaft can be sufficiently dealt with.

According to the invention described in claim 3, since the electric power steering motor is arranged below the center line of the steering column, a wide space can be secured between the electric power steering motor and the peripheral members. Assembling work such as wiring of the electric power steering motor is facilitated, and work efficiency can be improved.

According to the fourth aspect of the invention, the electric power steering motor is arranged inward of the extension line of the outer peripheral edge portion of the steering column cover for covering the steering column. There is no hindrance, and the electric power steering motor does not hinder an occupant during driving.

[Brief description of drawings]

FIG. 1 is a diagram showing a tilt structure of an electric power steering according to an embodiment of the present invention.

FIG. 2 is a diagram showing a pivoting operation of a tilt lever attached to an upper bracket.

FIG. 3 is an enlarged view of a substantially elongated hole of an upper bracket.

FIG. 4 is a plan view taken along the line AA of FIG.

FIG. 5 is a front view taken along the line BB of FIG.

FIG. 6 is a diagram showing a conventional electric power steering system.

[Explanation of symbols]

1 Steering column 2 upper bracket 3 lower bracket 4 steering wheel 8 Electric power steering motor 10 Tilt rotation axis 11 Steering column cover

Claims (4)

[Claims] 1. An electric power having a steering wheel at one end of a steering column, an electric power steering motor at the other end, and a tilt rotation shaft serving as a fulcrum when tilting the steering column. In the tilt structure of the steering, the tilt rotation shaft is arranged between the electric power steering motor and the steering wheel, and the tilt structure of the electric power steering. 2. The tilt of the electric power steering according to claim 1, wherein the tilt rotation shaft is provided on a vehicle body side bracket disposed on a vehicle rear side of the electric power steering motor. Construction. 3. The electric power steering motor,
The tilt structure for an electric power steering according to claim 1, wherein the tilt structure is disposed below a center line of the steering column. 4. The electric power steering motor,
The electric power steering system according to any one of claims 1 to 3, wherein the steering column cover is arranged between an extension line of an outer peripheral edge of the steering column cover and a center line of the steering column. Tilt structure.