JPH08295246A - Tilt steering system - Google Patents

Abstract

PURPOSE: To realize such a structure as preventing noise based on the vibration of a compression coil spring from occurring inexpensively without using excessive parts. CONSTITUTION: A compression coil spring 26 to support the weight of a rear steering column 4a is set up in a state that both the front and rear ends are offset. In consequence, a bending direction of this coil spring 26 might not be suddenly changed and noise is preventable from occurring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The tilt type steering device according to the present invention relates to an improvement of a portion for supporting a steering column which constitutes a steering device for an automobile so as to be swingable with respect to a vehicle body. This prevents the generation of unusual noise.

[0002]

2. Description of the Related Art A steering wheel height adjusting device, which is a so-called tilt-type steering device, has been known in which the height of the steering wheel can be changed according to the physique and driving posture of a driver. . As such a tilt type steering device, a device described in, for example, Japanese Utility Model Publication No. 2-34145 is conventionally known.

The tilt type steering device described in this publication is of a so-called swing type and is constructed as shown in FIGS. In order to insert the steering shaft 1, the tubular steering column 2 is
Front steering column 3 and rear steering column 4
It is divided into two parts. The two steering columns 3 and 4 are connected by a support bracket 5 that is supported and fixed to the vehicle body. The rear steering column 4 among them is swingable around the horizontal shafts 6, 6 provided on the support bracket 5. Further, in the steering shaft 1, the rear end portion (right end portion in FIG. 6) of the front steering shaft 22 and the front end portion (left end portion in FIG. 6) of the rear steering shaft 23 are connected by a universal joint 24. The displacement center of the universal joint 24 exists on an extension line of the central axes of the horizontal shafts 6, 6. Further, between the support bracket 5 and the rear steering column 4, there is provided a locking mechanism which can be engaged and disengaged by a tilt lever 7 which swings about the horizontal shafts 6, 6.

More specifically, the dashboard 8
The front end of the rear steering column 4 (the left end in FIGS. 5, 6 and 8) is pivotally supported on the support bracket 5 by the horizontal shafts 6 provided on the support bracket 5 fixed to the vehicle body on the lower surface of the vehicle. There is. A first engaging member 9 is fixed to the lower surface of the rear steering column 4. The lower surface of the first engaging member 9 forms an arcuate convex surface centered on the horizontal axes 6 and 6, and the first engaging teeth 10 are formed on the lower surface.

On the other hand, another horizontal shaft 11 provided on the support bracket 5 is engaged with and disengaged from the first engaging member 9 as the tilt lever 7 swings. Is pivoted at the front end (the left end in FIGS. 6 and 8). The upper surface of the rear end portion of the second engaging member 12 (the upper surface of the right end portion in FIG. 6) is disengageable with the first engaging teeth 10 formed on the lower surface of the first engaging member 9. The second engagement tooth 13 is formed. Further, an intermediate portion of the tilt lever 7 is pivotally supported on the horizontal shafts 6, 6. Then, a roller 15 is supported on a shaft 14 having its lower end connected to the lower end of the tilt lever 7.
The upper surface of 5 is brought into contact with the lower surface of the second engaging member 12. Further, a swing plate 16 fixed to the tilt lever 7 is provided.
The second engaging member 12 is formed in the slanted elongated hole 17 formed in
The pin 18 protruding from the side surface of the is engaged.

Since the tilt lever 7 is swung counterclockwise in FIG. 6, the roller 15 causes the roller 15 to move to the rear end (the right end in FIG. 6) of the second engaging member 12. At the same time as retracting from below, the rear end of the second engaging member 12 is displaced downward based on the engagement between the inclined elongated hole 17 and the pin 18.

As a result, the second engaging teeth 13 formed on the upper surface of the rear end of the second engaging member 12 and the lower surface of the first engaging member 9 fixed to the lower surface of the rear steering column 4 are provided. The engagement with the one engagement tooth 10 is released. In this state, (the pin 19 protruding from the side surface of the rear steering column 4
The rear steering column 4 becomes swingable about the horizontal shafts 6 and 6 within a range in which the rear steering column 4 can be displaced inside the arcuate elongated hole 20 formed in the support bracket 5. Based on this swing, the height position of the steering wheel 25 fixed to the rear end of the steering shaft 1 inserted through the inside of the rear steering column 4 can be freely adjusted.

When the height position of the steering wheel 25 is adjusted in this manner, the tilt lever 7 is moved to the position shown in FIG.
Rock clockwise. With this swing, the roller 15 enters below the rear end of the second engaging member 12 and pushes the rear end of the second engaging member 12 upward. Then, the second engaging teeth 13 formed on the upper surface of the rear end portion,
The first engaging teeth 10 formed on the lower surface of the first engaging member 9 fixed to the lower surface of the rear steering column 4 are engaged. As a result, the rear steering column 4 does not swing about the horizontal shafts 6 and 6, and the steering wheel 25 is held at the adjusted height position. The tilt lever 7 has a tension spring 21 so that the tilt lever 7 shown in FIG.
Since the elastic force to swing in the clockwise direction is imparted to the roller 15 from below the second engaging member 12,
There is no careless evacuation.

In the case of the tilt type steering device constructed as described above, a spring is provided between a portion fixed to the support bracket 5 and a portion fixed to the rear steering column 4, and the rear steering is provided. It is necessary to support the weight of the portion that swings around the horizontal axes 6 and 6 together with the column 4. The reason for this is as follows. A steering shaft 1 and a steering wheel 25 are supported by the rear steering column 4 which swings about the horizontal shafts 6, 6. Therefore, the weight of the portion that swings about the horizontal axes 6 and 6 is considerably increased. Therefore, if this weight is not supported by the spring, the rear steering column 4 vibrates downward vigorously as soon as the engagement of the locking mechanism is disengaged, which may cause the driver's foot to be vigorously hit. Become. Also, the driver must adjust the height position of the steering wheel 25 while supporting the large weight.
Adjustment work becomes troublesome.

A tension spring or a compression coil spring is used as a spring for supporting the weight of the rear steering column 4. If a tension spring is used, it is arranged above the steering column 2.
On the other hand, when a sufficient space cannot be secured above the steering column 2, a compression coil spring is arranged below the steering column 2. 9 to 10 show a conventional structure in which a compression coil spring 26 is arranged below the steering column 2 for such a purpose.

The front end portion (left end portion in FIG. 9) of the compression coil spring 26 is fixed to a part of the support bracket 5 and extends downward from the front end portion (left end portion in FIG. 9) of the support bracket 5. Rear side surface of the fixed side receiving piece 27 protruding to the left side (left side surface in FIG. 9)
Elastically abutted against. A folding piece 31 is folded on the rear side surface of the fixed side receiving piece 27 at a right angle to the rear side surface. Then, the front end portion of the compression coil spring 26 is fitted onto the folding piece 31. The rear end portion (right end portion in FIG. 9) of the compression coil spring 26 is fixed to a swing bracket 29 that constitutes the rear steering column 4a together with the column tube 28, and the front end portion of the swing bracket 29 ( It is elastically abutted on the front side surface (left side surface in FIG. 9) of the rocking side receiving piece 30 which projects downward from the left end portion in FIG. A circular concave hole 32 is formed in the front side surface of the swing side receiving piece 30 in a direction perpendicular to the front side surface. Then, the rear end portion of the compression coil spring 26 is fitted in the concave hole 32. By assembling the compression coil spring 26 in this manner, the compression coil spring 26 elastically bulges between the fixed-side receiving piece 27 and the swing-side receiving piece 30, and the horizontal shaft 6 together with the rear steering column 4a. , 6 to support the weight of the part that swings.

In the conventional structure shown in FIGS. 9 to 10, the rear steering column 4a is in a neutral state (the central axis of the front steering column 3 and the central axis of the rear steering column 4a are aligned with each other, When the steering wheel is in the middle position), the central axis of the compression coil spring 26 is located on a straight line from the front end to the rear end. In other words, the center of the folded piece 31 and the center of the concave hole 32 are aligned, and the central axis of the front end portion of the compression coil spring 26 and this compression coil spring 26 are aligned.
The central axis of the rear end part of the rear end is the same. From such a neutral state, when the rear steering column 4a is swung counterclockwise in order to raise the height position of the steering wheel, the compression coil spring 26 as shown in FIG.
However, it is curved in a direction in which the lower surface side is convex in an arc shape. On the other hand, when the rear steering column 4a is swung clockwise to lower the height position of the steering wheel, as shown in FIG.
However, it is curved in a direction in which the upper surface side is convex in an arc shape. A structure for supporting the weight of the rear steering column 4a by using the compression coil spring 26 that is aligned in the neutral position is described in, for example, JP-A-1-127453.

In the structure shown in FIGS. 9 to 12, the structure of the locking mechanism provided between the portion fixed to the rear steering column 4a and the portion fixed to the front steering column 3 is the same as that shown in FIG. 8 is slightly different from the structures shown in FIGS. That is, in the structure shown in FIGS. 9 to 12, the first engaging member 9a having the first engaging teeth 10a that are straight in the shape of a rack formed on the lower surface is used as the rear end portion of the front steering column 3. It is fixed to the lower surface of the support bracket 5 fixed to. In addition, the second engaging teeth 13 which are also linear in a rack shape
The rear end portion of the second engaging member 12a having a formed on the upper surface of the front end portion thereof is pivotally supported by the horizontal shaft 11a on the lower surface of the front end portion of the rear steering column 4a. Then, by the tilt lever (not shown), the first and second engaging teeth 10
A and 13a can be freely engaged and disengaged. Note that such a locking mechanism is not an essential part of the present invention, and the operation itself is similar to the structure shown in FIGS. Further, since a more specific structure of the locking mechanism shown in FIGS. 9 to 12 is described in detail in Japanese Patent Application No. 6-123907, detailed description thereof will be omitted in this specification.

[0014]

In the case of the conventional tilt type steering device configured and used as described above, the compression coil spring 26 produces an abnormal noise as the rear steering column 4a swings. That is, when the direction of the force applied from both ends of the compression coil spring 26 is continuously changed while applying the force in the compression direction to the compression coil spring 26, the compression coil spring 26 vibrates at the moment when the neutral position is exceeded.
For example, when the rear steering column 4a is changed from the state shown in FIG. 11 through the state shown in FIG. 9 to the state shown in FIG. 12, at the moment of passing the neutral position shown in FIG.
The bending direction of the compression coil spring 26 suddenly changes, and the compression coil spring 26 vibrates. Then, based on this vibration, the compression coil spring 26 produces an abnormal noise, which gives an occupant such as a driver discomfort. Of course, such abnormal noise is shown in Figure 1.
It also occurs when changing from the state shown in FIG. 2 to the state shown in FIG. 11 through the state shown in FIG.

In order to prevent such an unpleasant noise, the conventional compression coil spring 26 is covered with a member having a vibration damping property such as a rubber tube, or the end surface of the compression coil spring 26 and the coil portion are covered. The inner peripheral side was guided by a synthetic resin member. However, such a conventional structure requires a separate component to prevent the generation of abnormal noise, which is a cause of increasing the manufacturing cost of the tilt type steering device. The tilt type steering device of the present invention was invented in view of such circumstances.

[0016]

The tilt type steering device of the present invention, like the above-mentioned conventional tilt type steering device, is rotatably supported only in the front steering column and inside the front steering column. Front steering shaft, a support bracket fixed to the vehicle body while the rear end of the front steering column is supported and fixed, a horizontal shaft provided in a portion fixed to the support bracket, and a horizontal shaft A rear steering column whose front end is pivotally supported by a shaft, a rear steering shaft which is rotatably supported inside the rear steering column, a front end of the rear steering shaft and a rear end of the front steering shaft. A universal joint that connects the rear steering column and the front steering wheel. A locking mechanism that is provided between the column and a fixed portion to prevent swinging of the rear steering column around the horizontal axis when engaged, and a front end portion of the fixed portion to the support bracket. A compression coil spring is provided which elastically abuts a rear end portion of a portion fixed to the rear steering column to support the weight of a portion swinging around the horizontal axis together with the rear steering column.

Particularly, in the tilt type steering device of the present invention, the central axis of the front end portion of the compression coil spring and the central axis of the rear end portion of the compression coil spring are centered on the horizontal axis. Disagreement over the entire swing range of the rear steering column. Moreover, the central axis of the front end portion is displaced in the same direction with respect to the central axis of the rear end portion over the entire swing range.

[0018]

With the tilt type steering apparatus of the present invention constructed as described above, the operation itself of adjusting the height position of the steering wheel according to the physique of the driver is the same as that of the conventional structure described above. In particular, in the case of the tilt type steering device of the present invention, the compression coil spring that supports the weight of the portion that swings around the horizontal axis together with the rear steering column is displaced in the same direction over the entire swing range. Therefore, the compression coil spring does not vibrate significantly. Therefore, it is possible to prevent an unpleasant noise from being generated by the compression coil spring without using a separate component to prevent vibration.

[0019]

1 to 4 show an embodiment of the present invention.
The feature of the present invention is that the rear side surface (right side surface of FIGS. 1, 3 and 4) of the fixed side receiving piece 27 fixed to the support bracket 5 and the swing bracket 29 are supported to support the weight of the rear steering column 4a. The front side surface of the swing-side receiving piece 30 fixed to (Fig. 1,
It is characterized by the structure of the portion where the compression coil spring 26 is disposed between the left and right side surfaces 3 and 4. The structure and operation of the other parts are the same as those of the conventional structure shown in FIGS. 5 to 8 or 9 to 12 described above, and therefore, the same parts are designated by the same reference numerals to omit or simplify duplicate description. Hereinafter, the characteristic part of the present invention will be mainly described.

A folding piece 31 is folded on the rear side surface of the fixed side receiving piece 27 at a right angle to the rear side surface, and the front end portion of the compression coil spring 26 (the lower left end portion of FIGS. 1, 3 and 4).
Is externally fitted to this folding piece 31. Further, a circular concave hole 32 is formed in the front side surface of the rocking side receiving piece 30 in a direction perpendicular to the front side surface, and the rear end portion of the compression coil spring 26 (see FIGS. The upper right end) is fitted in the recess 32. In the case of the tilt type steering device of the present invention, unlike the case of the conventional structure described above, the central axis α of the folding piece 31 and the central axis β of the concave hole 32 do not coincide with each other. In the case of the illustrated embodiment, when the rear steering column 4a is set to the neutral position as shown in FIG. 1, both the central axes α and β are parallel to each other, but the central axis β of the concave hole 32 is folded up. It exists in a portion closer to the steering shaft 1 than the central axis α of the piece 31.

Therefore, the rear steering column 4a is provided.
Even if is in the neutral position, the compression coil spring 26 is not aligned. In the case of the illustrated embodiment, more specifically, the lower surface side is convexly curved except for the vicinity of the rear end portion fitted into the concave hole 32. Then, even if the rear steering column 4a is swung counterclockwise to the state shown in FIG. 3 in order to raise the steering wheel from this state, the lower surface side of the compression coil spring 26 remains curved convexly. . Incidentally, when the rear steering column 4a is swung to the state shown in FIG. 3 in order to raise the steering wheel in this manner, the rear end of the compression coil spring 26 becomes substantially linear. Further, even if the rear steering column 4a is rocked clockwise to the state shown in FIG. 4 in order to lower the steering wheel from the neutral state, the compression coil spring 2 is
No. 6 remains convexly curved on the lower surface side except for the vicinity of the rear end portion fitted into the concave hole 32.

As described above, in the tilt type steering device of the present invention, the entire compression coil spring 26 does not instantaneously change the bending direction. For this reason, even if a member for preventing vibration is not provided, the compression coil spring 26 does not generate an abnormal noise that gives an occupant an uncomfortable feeling. Although the rear end of the compression coil spring 26 is located closer to the steering shaft 1 than the front end in the illustrated embodiment,
The displacement directions of these both ends may be opposite to those shown in the figure.

[0023]

Since the present invention is constructed and operates as described above, it is possible to obtain at a low cost a structure that does not give an occupant an unpleasant feeling.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of an essential part showing an embodiment of the present invention.

FIG. 2 is a view seen from the upper right in FIG. 1 in the axial direction.

FIG. 3 is a view similar to FIG. 1, showing a state in which a rear steering column has been pivotally displaced upward.

[Fig. 4] Similarly, showing a state in which the oscillating displacement is made to the lowest,
The same figure as FIG.

FIG. 5 is a side view showing an example of a conventionally known tilt type steering device.

FIG. 6 is an enlarged cross-sectional view of part A in FIG.

7 is a sectional view taken along line BB of FIG.

FIG. 8 is a partially cutaway view taken in the direction of arrow C in FIG. 6;

FIG. 9 is a vertical cross-sectional side view of essential parts showing a conventional structure in which a compression coil spring is incorporated.

FIG. 10 is a view seen from the upper right side in FIG. 9 in the axial direction.

FIG. 11 is a view similar to FIG. 9, showing a state in which the rear steering column is pivotally displaced upward.

FIG. 12 is a view similar to FIG. 9 showing a state in which it is also pivotally displaced to the lowest position.

[Explanation of symbols]

 1 Steering Shaft 2 Steering Column 3 Front Steering Column 4, 4a Rear Steering Column 5 Support Bracket 6 Horizontal Axis 7 Tilt Lever 8 Dashboard 9, 9a First Engaging Member 10, 10a First Engaging Teeth 11, 11a Horizontal shaft 12, 12a Second engaging member 13, 13a Second engaging tooth 14 Shaft 15 Roller 16 Oscillating plate 17 Inclined elongated hole 18, 19 Pin 20 Circular elongated hole 21 Tension spring 22 Front steering shaft 23 Rear steering shaft 24 Universal joint 25 Steering wheel 26 Compression coil spring 27 Fixed side receiving piece 28 Column tube 29 Swing bracket 30 Swing side receiving piece 31 Folding piece 32 Recessed hole

Claims (1)

[Claims] 1. A front steering column, a front steering shaft rotatably supported inside the front steering column, and a rear steering end of the front steering column fixed to a vehicle body in a supported and fixed state. Support bracket, a horizontal shaft provided in a portion fixed to the support bracket, a rear steering column whose front end is pivotally supported by the horizontal shaft, and only the inside of the rear steering column can freely rotate. A supported rear steering shaft, a universal joint connecting the front end of the rear steering shaft and the rear end of the front steering shaft, a portion fixed to the rear steering column and a portion fixed to the front steering column. Is provided between the rear steering column and the rear steering column about the horizontal axis when engaged. A locking mechanism for preventing movement and a front end portion of the portion fixed to the support bracket and a rear end portion of the portion fixed to the rear steering column are elastically abutted, respectively. In a tilt type steering device including a compression coil spring that supports the weight of a portion that swings about the horizontal axis, a center axis of a front end portion of the compression coil spring and a center axis of a rear end portion of the compression coil spring. And are inconsistent over the entire swing range of the rear steering column about the horizontal axis, and the central axis of the front end portion is the full swing with respect to the central axis of the rear end portion. Tilt type steering device characterized by being displaced in the same direction over the range of motion.