JPH0755181Y2 - Electric tilt steering - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an electric tilt steering, and more particularly to improvement of a connecting portion of means for adjusting a tilt amount of a rear column with respect to a front column.

(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 handle (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, 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 attached 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 9 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 has an output shaft 15 extending vertically in the central space.
And the motor 17 is attached to the front end projecting portion. The upper and lower ends of the output shaft 15 are supported by the base frame 13 via bearings 16, a screw groove is formed in the center, and the output gear 15 is located below the output shaft 15.
18 is attached integrally.

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 shaft portion 192 extending left and right from the main portion 191, and the pair of shaft portions 192 are arranged parallel to the tilt center line 1 and will be described later. It is pivotally attached to the eccentric cam 22.

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

The cam bearing 20 is a ball bearing, and the eccentric cam 22 is pivotally supported in the inner ring of the cam bearing 20. The eccentric cam 22 pivotally supports a pair of shaft portions 192 at a position deviated from the tilt operation center line 1 by a predetermined amount.

For this reason, as shown in FIG. 5, with respect to the locus m that the output nut 19 side moves in the longitudinal direction of the output shaft due to the rotation of the output shaft 15, the locus n that the shaft portion 192 moves around the tilt center line 1 is set. The shift in side view can be absorbed by the synergistic action of the eccentric cam 22 supported by the lever portion 701 via the cam bearing 20 and the shaft portion 192 pivotally supported by the eccentric cam 22.

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, this type of electric tilt steering is a problem because it requires a certain amount of skill and time to connect the lever 701 side of the tilt bracket 7 to the base frame 13 side. . That is, at the time of connecting the output nut 19 on the base frame 13 side and the eccentric cam 22 on the lever portion 701 side, it is necessary to make the front and rear, left and right, and upper and lower relative positions of both sides face each other, and then to assemble them. There is.

However, the output nut 19 is sequentially attached to the output shaft 15, the base frame 13, and the main bracket 3 by welding or bolting, and unless the accuracy of each member itself and the mutual assembly accuracy are sufficiently secured, these It takes a lot of time and technology to adjust the shim for assembling, and lacks mass productivity.

An object of the present invention is to provide an electric tilt steering which can improve mass productivity.

(Means for Solving the Problems) In order to achieve the above object, an electric tilt steering device of the present invention includes a front main shaft in a front column and a rear main shaft in a rear column, which are connected to each other through a universal joint. , A column bearing pivotally attached to the outer cylinder of the front column so that the front end of the rear column can swing around a tilt center line intersecting the center of the universal joint, and extends forward from the front end of the outer cylinder of the rear column. In addition, it is pivotally supported by a lever part with a tilt operation pin attached to the tip part and a bracket fixed to the vehicle body side in a direction substantially along the trajectory when the lever part swings around the tilt center line. And has an output shaft with a screw groove that is rotated by a rotation source, and an output nut that is screwed onto the output shaft and that is connected with the tilt operation pin. An eccentric cam pivotally supporting the tilt operation pin at an eccentric position is pivotally attached to the output nut, in which a ball joint outer frame portion that rotatably supports the ball portion of the ball joint is rotatably supported. The tilt operation pin is eccentric as long as it can absorb a relative deviation between the tilt operation pin that moves along the swing path of the lever portion and the center position of the eccentric cam that moves along the movement path of the output nut. It is characterized in that it is formed so as to be eccentric with respect to the center position of the cam.

(Operation) An eccentric cam is pivotally mounted in the spherical portion of the ball joint, and the tilt operation pin on the lever portion side is pivotally mounted by being eccentric in the eccentric cam. Therefore, the shift in the front-rear direction between the pivot end of the lever portion and the output nut is absorbed by the relative movement of the ball portion and the tilt operation pin that are connected to each other via the eccentric cam, and the ball joint causes the tilt on the lever portion side. It is possible to absorb the front and rear, left and right, and upper and lower twists of the operation pin and the output nut.

(Embodiment) FIGS. 1 and 2 show a tilt angle adjusting means B which is a main part of an electric tilt steering according to 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, and therefore, the description of the overlapping parts 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 is pivotally supported by a base frame 13 supported by the main bracket 3, and an output nut 30 is screwed into a screw groove of this shaft.

The output nut 30 includes a rectangular main portion 301 and an outer frame portion 302 extending from the rear surface thereof. The outer frame portion 302 is a sideways recessed portion 30.
3 is formed, the bearing member 31 is fitted therein, and the stop pin 32
To prevent the withdrawal. The bearing member 31 and the outer frame portion 302 are rotatably attached to the center of the bearing member 31 and the outer frame portion 302 with the sphere portion 33 held irremovably. 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 outer frame portion 30
2, bearing member 31, ball portion 33, tilt operation pin 34, eccentric cam 3
5 constitutes the ball joint BJ.

Here, the eccentric cam 35 has a cylindrical shape as shown in FIG. 3, and is rotatably fitted around a center line 12 that intersects with the center point O1 of the spherical portion 33. In this eccentric cam 35, the center line l2
A tilt operation pin 34 that rotates about a tilt center line 1 (extending in the direction perpendicular to the paper surface) at a position deviated by b is pivotally mounted.

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 lever portion 701, and the tilt operating pins 34 are integrally formed on the connecting ends 702 along the tilt operating center line 1. The output nut 30 side and the lever portion 701 side are pivotally attached to each other via this pin.

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. 3). At this time, the eccentric cam 35 in the output nut 30 and the tilt operation pin 34 in the eccentric cam 35 rotate relative to each other, and the operation pin 34
Moves along the n locus (see FIG. 3). For this reason,
The lever portion 701 side smoothly swings in conjunction with the output nut 30, the rear steering column 8 side rotates with respect to the rear steering column 8 around the tilt center line l, and the tilt angle is switched to a desired tilt angle and held. .

Such an electric tilt steering has its output nut
At the time of assembly for connecting the 30 side and the connecting end 702 side of the lever end, the deviation of the relative position in the front-rear direction X can be absorbed by the action of the eccentric cam 35, and the tilt operating pin 34 supported by the eccentric cam 35 is connected. The twist relative to the 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.

(Effect of device) As described above, in the electric tilt steering device of the present invention, since the ball joint and the eccentric cam are interposed between the output nut and the lever portion, the relative displacement between the two can be easily absorbed, and The advantages are that the accuracy can be relaxed, assembly preparation can be facilitated, and mass production can be facilitated.

[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. 1,8 ... Steering column, 2,9 ... Outer cylinder, 3 ... Main bracket, 4,5 ... Main shaft, 7 ... Tilt bracket, 15 ... Output shaft, 17 ... Motor, 30 ...
… Output nut, 33 …… Ball part, 34 …… Tilt operation pin, 35
... eccentric cam, l ... tilt center line, B ... tilt angle adjusting means.

Claims (1)

[Scope of utility model registration request] 1. A front main shaft in a front column and a rear main shaft in a rear column, which are connected to each other via a universal joint, and a tilt centerline that intersects a front end of the rear column with a center point of the universal joint. A column bearing pivotally attached to the outer cylinder of the front column, a lever portion that extends forward from the front end of the outer cylinder of the rear column and has a tilt operation pin attached to the tip, and the tilt centerline An output shaft with a screw groove, which is pivotally supported by a bracket fixed to the vehicle body and is rotated in a direction substantially along the locus when the lever part swings, and which is rotated by a rotation source; It has an output nut to which the tilt operation pin is connected while being screwed to a shaft, and the output nut is integrally formed with a ball joint outer frame portion for rotatably supporting the ball portion of the ball joint, An eccentric cam that pivotally supports the tilt operation pin at an eccentric position is pivotally mounted in the recording ball portion, and moves along the movement path of the tilt operation pin and the output nut that moves along the swing path of the lever section. An electric tilt steering having a configuration in which the tilt operation pin is formed so as to be eccentric with respect to the center position of the eccentric cam so as to be able to absorb a relative deviation from the center position of the eccentric cam.