JPH0754053Y2 - Electric tilt steering - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention is an electric tilt steering system, and in particular, an electric tilt steering system which is improved so that the tilt amount of the rear column with respect to the front column is increased.

<Prior Art> A steering column of a vehicle is attached to a vehicle body at a predetermined inclination angle. In particular, a tilt mechanism is used to facilitate the getting on and off of the occupant and to make the driving posture suitable for the occupant. Of these, in particular, an electric tilt steering may be adopted in order to further improve the operability of the tilt steering.

Many electric tilt steering devices have a structure in which a front part connected to the steering gear box side and a rear part to which a steering handle is attached are connected via a universal joint.

By the way, means for electrically operating the rear steering column to the desired tilt angle with respect to the front steering column is configured as shown in, for example, FIGS. 4 to 5.

That is, the front steering column 1 has its outer cylinder 2 welded with two brackets 3 and 3'having sufficiently enhanced rigidity, and is fixed to the vehicle body base side through the brackets. A tilt bracket 7 is welded to a front portion of an outer cylinder 9 of the rear steering column 8 and is connected and supported to the main bracket 3 on the front steering column 1 side via the tilt bracket 7.

Inside the outer cylinders 2 and 9, the front and rear main shafts 4,5
Are each pivoted. A front end of the front main shaft 4 is connected to a steering gear box side (not shown), and a rear end of the front main shaft 4 is connected to a rear main shaft 5 via a universal joint 6. Further, a steering wheel (not shown) is attached to the rear end of the rear main shaft 5.

Here, the main bracket 3 and the tilt bracket 7 are U-shaped in a plan view, and one end of each is welded to the outer cylinders 2 and 9 of the front and rear steering columns 1 and 8 to form a bifurcated shape. The other opposite ends are pivotally mounted via a pair of bearings 10 as column bearings. That is, the main bracket 3 on the front steering column 1 side and the tilt bracket 7 on the rear steering column 8 side have bifurcated bifurcated ends at a tilt center line long in the left-right direction intersecting the center point a of the universal joint 6. It is pivotally mounted around a shaft 1 through a spindle 11 and a column bearing 10.

Thus, the rear steering column 8 and the rear main shaft 5 are connected to the front steering column 1 and the front main shaft 4 supported on the vehicle body side so as to be tiltable about the tilt center line l, and the tilt angle at this time is Is adjusted and held by the tilt angle adjusting device A.

The tilt angle adjusting device A is mounted over the main bracket 3 and the tilt bracket 7.

Here, a substantially box-shaped base frame 13 having an open rear side is integrally attached to one side of the main bracket 3 by a bolt 14. The base frame 13 vertically supports an output shaft 15 which is a screw shaft in a central space, and a motor 17 is attached to a front end projecting portion thereof. The upper and lower ends of the output shaft 15 are supported by the base frame 13 via the bearings 16, a screw groove is formed in the center, and the output gear 18 is integrally attached to the lower part thereof.

The output gear 18 is connected to the drive shaft of the motor 17 via the gear train 12. Here, the motor 17 is connected to the motor controller 23, and the motor controller 23 is connected to the tilt switch 24.
Are connected. Therefore, the motor controller 23 operates the output shaft by the amount according to the command of the tilt switch 24.
Drive 15 to rotate.

An output nut 19 is screwed onto the output shaft 15. As shown in FIG. 6, the output nut 19 is composed of a main portion 191 and a tilt operating pin 192 extending left and right by the main portion 191, and the pair of tilt operating pins 192 are arranged parallel to the tilt center line l. It is pivotally attached to an eccentric cam 22 described later. The tilt operation center line, which is the axis line of the tilt operation pin 192, is the sixth line as l ₁ .
It is illustrated in the figure.

One end of the tilt bracket 7 is provided with a steering lever 701 extending forward from the tilt center line l, and a tip end of the steering lever 701 has a connecting end 7 that is bifurcated in plan view.
02 is formed. Here, the cam bearings 20 are attached to the pair of connecting ends 702 along the tilt operation center line l ₁ .

The cam bearing 20 is a ball bearing, and the eccentric cam 22 is pivotally supported in the inner ring thereof. The eccentric cam 22 pivotally supports a pair of tilt operation pins 192 at a position displaced from the center by a predetermined amount.

The reason for providing such an eccentric connection structure is as follows. That is, as shown in FIG. 5, when the output nut 19 moves in the up-down direction which is the longitudinal direction of the output shaft 15 due to the rotation of the output shaft 15, the rear steering column 8 rotates around the tilt center line l. As a result, the distance between the tilt center line l and the tilt operation center line l ₁ changes, but this change in distance is caused by the eccentric cam 22 supported by the steering lever portion 701 via the cam bearing 20 and the eccentric cam 22. This is because the tilt operation pin 192 pivotally supported by the eccentric cam 22 absorbs it in cooperation.

This type of electric tilt steering wheel has a tilt switch 24
It is possible to switch and hold the rear steering column 8 side to a desired tilt angle in accordance with a switching operation such as.

<Problems to be Solved by the Invention> By the way, as shown in FIG. 4, the tilt amount of the electric steering is determined by the distance L ₁ between the tilt center line ₁ and the end of the main shaft 5 and the tilt center line. It is determined by the ratio K of the distance L ₂ between l and the tilt operation center line l ₁ . That is,
The larger the ratio K = L ₁ / L ₂ is, the larger the tilt amount can be obtained, but it is not easy to change the distances L ₁ and L ₂ . This is because other parts are complicated around the steering wheel, and it is not easy to change the position and shape of each part of the electric steering wheel together with these parts. Therefore, the advent of a technology that can easily increase the tilt amount without changing the positions of components has been desired.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an electric tilt steering which can easily increase the tilt amount without changing the positions of components.

<Means for Solving the Problems> The structure of the present invention that achieves the above-mentioned object is provided with a front main shaft in a front steering column and a rear main shaft in a rear steering column, which are connected to each other through a universal joint, and the rear portion. A column bearing pivotally attached to the outer cylinder of the front steering column so that the front end of the steering column can swing in a vertical plane around a tilt center line intersecting the center point of the universal joint, and the front end of the outer cylinder of the rear steering column. A steering lever that extends forward, an output shaft that is a screw shaft that is pivotally supported by a bracket that is fixed to the vehicle body side, and that is rotated by a rotation source, and that is screwed into the output shaft and accompanies the rotation of the output shaft. In an electric tilt steering having an output nut that moves in the vertical direction, the output nut The front end is fixed to the, and extends rearward and moves up and down as the output nut moves up and down, an eccentric cam rotatably attached to the operation lever, and an eccentric cam pivotally supported at an eccentric position. The tilt lever has a tilt operation pin that connects the operation lever and the tip of the steering lever via the eccentric cam, and the operation force transmitted through the tilt operation pin along with the vertical movement of the output nut causes the steering lever to move through the steering lever. It is characterized in that the steering column is tilted.

<Operation> According to the present invention having the above structure, the tilt amount is determined by the ratio of the distance between the tilt center line and the end of the rear main shaft to the distance between the tilt center line and the tilt operation pin. .

<Embodiment> An embodiment of the present invention will be described in detail below with reference to the drawings.

1 and 2 show a tilt angle adjusting means B which is a main part of an electric tilt steering device as an embodiment of the present invention. The electric tilt steering here is configured in the same manner as the conventional electric tilt steering shown in FIGS. 4 and 5 except for the tilt angle adjusting means B. Therefore, the same parts are denoted by the same reference numerals. The description of the overlapping portions will be omitted.

With respect to the main bracket 3 on the front steering column 1 side, the tilt bracket 7 on the rear steering column 8 side can perform a tilt operation with the tilt center line 1 as a fulcrum. On the other hand, an output shaft 15 which is a screw shaft is pivotally supported on a base frame 13 supported by the main bracket 3, and an output nut 30 is screwed onto the output shaft 15.

This output nut 30 has an operating lever that extends from its rear surface.
The front end of 36 is integrally fixed. A lateral recess 303 is formed in the operating lever 36, and the bearing member 3 is formed therein.
1 is fitted and the stop pin 32 prevents the detachment. A ball 33 is provided at the center of the bearing member 31 and at the rear end of the operating lever 36.
Is held irremovably and is pivotally attached. An eccentric cam 35 having a tilt operation pin 34 pivotally supported at an eccentric position is pivotally attached to the center of the spherical portion 33. Here, the operating lever 36, the bearing member 31, the ball portion 33, the tilt operation pin 34, and the eccentric cam 35 constitute a ball joint BJ.

Here, the eccentric cam 35 has a cylindrical shape as shown in FIG. 3, and is rotatably fitted to the spherical portion 33. This eccentric cam
A tilt operation pin 34, which rotates about a position deviated from the tilt operation center line l ₂ by b, is pivotally mounted inside 35.

On the other hand, a pair of connecting ends 702 having a bifurcated shape in a plan view is formed at the tip of the steering lever 701.
The tilt operation pin 34 is integrally attached to the 02, and the output nut 30 side and the steering lever 701 side are pivotally connected to each other via the tilt operation pin 34. That is, the output nut 30 and the steering lever 701 are connected by the operating lever 36 via the ball joint BJ.

In such an electric tilt steering, the motor controller 23 outputs a drive current to the motor 17 in response to a switching command issued by a switching operation of the tilt switch 24. As a result, the output shaft 15 rotates and the output nut 30 moves along the m locus (see FIG. 1). At this time, the eccentric cam 35 in the actuating lever 36 and the tilt operating pin 34 in the eccentric cam 35 relatively rotate, and the tilt operating pin 34 moves along the n locus (see FIG. 3). For this reason, the steering lever 701 side swings smoothly in conjunction with the output nut 30 and the operating lever 36, and the rear steering column 8 side rotates with respect to the rear steering column 8 around the tilt center line 1 to obtain a desired tilt angle. Is switched to and held.

The tilt amount at this time is the ratio of the distance L ₁ (see FIG. 4) to the distance L ₃ between the tilt center line 1 and the tilt operation center line l _2.
Determined by K ₁ . This ratio K ₁ is the ratio K in the prior art.
Even if the distance L ₁ is the same, a larger tilt amount can be obtained.

Incidentally, the distance L ₂ (see FIG. 4) in the conventional technique corresponds to the distance L ₂ between the tilt center line 1 and the axis of the output shaft 15 in the present embodiment, as shown in FIG. Therefore, the tilt amount can be increased without changing the positions and shapes of the output shaft 15 and the steering lever 701.

Further, in the electric tilt steering according to the present embodiment, when the output nut 30 side and the connecting end 702 side of the tip end of the steering lever 701 are connected, the eccentric cam 35 acts to shift the relative position in the front-rear direction X. And the relative twist between the tilt operation pin 34 supported by the eccentric cam 35 and the connecting end 702, that is, each twist in the front, rear, left, right, and top can be absorbed by the ball joint, and the assembling can be facilitated. You can

That is, in the electric tilt steering according to the present embodiment, since the ball joint BJ is interposed between the operating lever 36 and the steering lever 701, the relative displacement between the two can be easily absorbed, the precision of the parts can be eased, and the assembly There are advantages that it is easy to prepare and mass-produce.

<Effects of the Invention> As described in detail with the embodiments above, according to the present invention, the distance between the tilt center and the tilt operation center can be made smaller than before without changing the position and shape of the parts. Therefore, the tilt amount can be easily increased.

[Brief description of drawings]

1 is a cutaway side sectional view of a tilt angle adjusting device used in an electric tilt steering according to an embodiment of the present invention, FIG. 2 is a cutaway flat sectional view of the tilt angle adjusting device of FIG. 1, and FIG. A sectional view taken along the line III-III in FIG. 2, FIG. 4 is a schematic plan view of a conventional electric tilt steering wheel, FIG. 5 is a schematic side view of the electric tilt steering wheel of FIG. 4, and FIG. FIG. 3 is a cutaway flat sectional view of a tilt angle adjusting device used for tilt steering. In the drawing, 1,8 is a steering column, 2,9 is an outer cylinder, 3 is a main bracket, 4,5 is a main shaft, 7 is a tilt bracket, 15 is an output shaft, 17 is a motor, 30 is an output nut,
34 is a tilt operation pin, 35 is an eccentric cam, 36 is an operating lever,
701 is a steering lever, 1 is a tilt center line, and B is a tilt angle adjusting means.

Claims (1)

[Scope of utility model registration request] 1. A front main shaft in a front steering column and a rear main shaft in a rear steering column, which are connected to each other via a universal joint, and a tilt at which a front end of the rear steering column intersects a center point of the universal joint. A column bearing pivotally attached to the outer cylinder of the front steering column so as to be swingable in a vertical plane around the center line, a steering lever extending forward from the front end of the outer cylinder of the rear steering column, and fixed to the vehicle body side. In an electric tilt steering having an output shaft that is a screw shaft that is pivotally supported by a bracket that is rotated by a rotation source, and an output nut that is screwed onto the output shaft and that moves in the up-down direction with the rotation of the output shaft, The output nut is fixed to the front end and extends rearward. Of the operating lever, an eccentric cam rotatably attached to the operating lever, and an eccentric cam that is pivotally supported at an eccentric position. It has a tilt operation pin that connects the tip end portion, and is configured to tilt the steering column via a steering lever by an operation force transmitted through the tilt operation pin as the output nut moves up and down. Electric tilt steering to be.