JP2554195Y2 - Electric telescopic steering system - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric telescopic steering device used for automobiles and the like.

[0002] In this specification, the term spline is used to include all spline style joints such as splines and serrations. In this specification, the left side of FIG. 1 is referred to as front, and the right side of FIG.

[0003]

2. Description of the Related Art An electric telescopic steering apparatus of this type includes a hollow outer shaft having a serration formed on an inner periphery thereof, and an inner serration formed on an outer periphery thereof so as to mesh with the serrations of the outer shaft and inserted into the outer shaft. 2. Description of the Related Art There is known a steering shaft including a steering shaft having a shaft, and the steering shaft can be expanded and contracted by rotation of an electric motor. In this steering device, in order to determine the stroke amount of the steering shaft,
It is necessary to regulate the relative positions of the outer shaft and the inner shaft in the axial direction.

Therefore, conventionally, the first positioning member is fixedly provided on one of the outer shaft side and the inner shaft side outside the outer shaft, and the first positioning member on the front and rear sides of the first positioning member on the other side. A second positioning member that abuts on the first positioning member and regulates the relative position of the two shafts in the axial direction is fixedly provided at the portion (see Japanese Utility Model Laid-Open No. 63-42475).

[0005]

However, in the conventional electric telescopic steering apparatus, since the positioning member is provided outside the outer shaft,
Therefore, there is a problem that the space for this becomes large, the work of assembling into a car or the like becomes troublesome, and it becomes a hindrance when arranging other devices.

An object of the present invention is to provide an electric telescopic steering apparatus which solves the above problem.

[0007]

The electric telescopic steering apparatus according to the present invention comprises a hollow outer shaft having a spline formed on the inner periphery, and a spline meshing with the spline of the outer shaft formed on the outer periphery. An electric telescopic type steering device comprising a steering shaft having an inner shaft inserted into the steering shaft, and the steering shaft being extended and contracted by rotation of the electric motor, wherein the front end of the inner shaft is A small-diameter shaft portion is provided in a forwardly protruding shape and fixed , and a first positioning member is fixedly provided on the inner periphery of the outer shaft, and on the outer periphery of the shaft portion on both front and rear sides of the first positioning member, The outer shaft and the inner shaft come into contact with the first positioning member, respectively. Second positioning member for regulating the relative axial position of the shaft is provided in a fixed shape, two
The three positioning members are fitted around the shaft portion.
It is detachably fixed to the shaft so as to hold the valve .

[0008] The electric telescopic steering described above.
In the device, the front end of the inner shaft is hollow.
The inner peripheral surface of the hollow part tapered toward the rear
Tapered, from the front end to the part around the hollow part
A plurality of slits extending in the axial direction are formed,
And a shaft portion behind the second positioning member on the rear side.
The rattling prevention member is fitted around the
Into the hollow at the front end of the inner shaft.
The push-out part that pushes and spreads the part around the hollow part
The rattling prevention member and the inner shaft are
Provision of means for pressing in the direction approaching the axial direction
Is preferred.

[0009]

[Function] Electric telescopic stearin of this invention
When the steering shaft is extended and contracted by the rotation of the electric motor, the first positioning member and the second positioning member come into contact with each other, so that the relative positions of the outer shaft and the inner shaft in the axial direction are regulated. Moreover, two second
2 The positioning member is a sleeve fitted around the shaft.
It is detachably fixed to the shaft so that it can be clamped
By changing the length of the sleeve,
It is possible to easily and accurately change the stroke amount of the
Can be.

The electrically driven telescopic steer of the present invention.
In the ring device, the front end of the inner shaft is hollow
And the inner peripheral surface of the hollow portion tapers rearward.
Tapered, with its front end at the periphery of the hollow
A plurality of slits extending in the axial direction from the
Rearward of the first and second positioning members on the rear side,
A rattling prevention member is fitted around the shaft to prevent rattling.
At the rear end of the stop member, inside the hollow at the front end of the inner shaft
A push-spread portion that fits and pushes the portion around the hollow portion
Is formed, and the rattling prevention member and the inner shaft are
Equipped with means for pressing in the direction approaching in the axial direction
And the above means makes the front end of the inner shaft rattle.
Press the rear ends of the prevention members so that they approach each other in the axial direction
Then, the outer peripheral surface of the push-spread portion of the rattling prevention member
It hits the inner peripheral surface of the front end of the female shaft. In front of inner shaft
Multiple slits extending in the axial direction around the edge
The part around the front end of the inner shaft
It is pushed outward in the radial direction by the push-out portion to open. This
Outer shaft spline and inner shaft spline
The occurrence of rattling at the meshing part with the line is prevented.
You.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an automobile steering system will be described below with reference to the drawings.
In the following description, the upper and lower sides in FIG. Further, left and right refer to forward with reference to the vertical direction of the paper surface of FIG.

FIG. 1 shows a telescopic operation unit of a steering device having a tilt operation function in addition to a telescopic operation function, and FIGS. 2 to 4 show each part thereof.

In FIG. 1, a tilt bracket (2) is provided at a rear portion of a fixing bracket (1) fixed to a vehicle body with a connecting pin.
(3) is attached so as to be rotatable up and down. The front end of the column tube (4) is fixed to the rear end of the tilt bracket (2).

A hollow outer shaft (6) constituting a steering shaft (5) in a column tube (4) is a ball bearing.
(7) It is rotatably supported via (8). The front of the hollow inner shaft (9), which also forms the steering shaft (5), is inserted from the rear into the rear of the outer shaft (6), and the steering wheel (11) is inserted into the rear end of the inner shaft (9). Installed. An adjustment rod (12) is passed through the inner shaft (9) from behind. At the rear end of the rattling adjusting rod (12), a head (12a) for rotating the rod (12) around the axis is integrally formed, and at the front end, a screw portion (12b) is formed. . A predetermined length of the front end of the rattling adjustment rod (12) is the inner shaft.
The sleeve (10) projects forward from the front end of (9), and a sleeve (10) and an anti-rattle member (13) are fitted around the projected portion (shaft) (12A) from the front.

A serration (14) is formed entirely on the inner peripheral surface of the outer shaft (6) except for a predetermined length portion at the front portion thereof. The portion where the serration (14) is not formed is indicated by (6A). The inner ring (8a) of the ball bearing (8) supporting the rear end of the outer shaft (6) has a small diameter portion formed on the outer peripheral surface of the rear end of the outer shaft (6) via a step (6a). (6b), and a retaining ring (15) is fitted on the rear side. Behind the retaining ring (15), in the small diameter portion (6b),
The front cylindrical part (16b) of the anti-tilt collar (16) of the inner shaft (9) is fixed by press-fitting.
(9) is slidably passed through the collar (16) in the axial direction.
A portion (16a) of the collar (16) fitted around the inner shaft (9) and a small-diameter portion (6
b) A synthetic resin bush (22) is interposed between the rear end face and the inner shaft (9) and the collar.
The generation of sound due to the gap existing between the portion (16) and the portion (16a) can be prevented. In addition, color (16)
The front end of the cylindrical portion (16b) presses the retaining ring (15) and the inner ring (8a) of the ball bearing (8) against the step (6a), and thereby is fixed to the outer shaft (6). Therefore, backlash in the axial direction between the ball bearing (8) and the outer shaft (6) is prevented. The rear end of the portion (6A) of the inner peripheral surface of the outer shaft (6) where the serration (14) is not formed is provided with a stopper (a first positioning member) for regulating the forward and backward positions of the inner shaft (9). ) (17) is installed.

A serration (18) meshing with the serration (14) of the outer shaft (6) is formed at a front end of the outer peripheral surface of the inner shaft (9) over a predetermined length. At the front end of the inner shaft (9), a tapered hole (19) tapering rearward is formed. Taper hole
A fool hole (20) is formed so as to be connected to the rear of (19).
Taper hole (19) and fool hole in inner shaft (9)
A plurality of slits (21) extending in the axial direction from the front end thereof are formed in the peripheral portion of (20) at intervals in the circumferential direction.

A flange (23) is rotatably mounted via a ball bearing (24) at an intermediate portion of the length of the outer peripheral surface of the inner shaft (9). A rear end portion of the telescopic operation screw shaft (26) extending forward and backward is fixed to the flange (23). Screw shaft (26) is tilt bracket
(2) is passed through a housing (27) integrally formed on the lower side. On the left side of the wall of the housing (27) when viewed from the steering wheel (11) side, a telescopic operation motor (28) is fixed to the right so as to be perpendicular to the screw shaft (26). The motor shaft (29) penetrates the wall of the housing (27) and protrudes inward, and the worm (30)
Has been fixed.

A screw nut (31) for telescopic operation is arranged in the housing (27) and meshed with the screw shaft (26). The screw nut (31) is rotatably supported by the housing (27) via two front and rear ball bearings (32) and (33). Between the two ball bearings (32) and (33), teeth (31a) meshing with the teeth (30a) of the worm (30) are formed on the outer peripheral surface of the screw nut (31).
(31) also serves as a worm wheel that forms a worm gear (34) together with the worm (30).

Thread portion at front end of rattling adjusting rod (12)
(12b) has a detent nut (36) screwed in,
The detent nut (36) fixes the sleeve (10) and the rattling prevention member (13), and the rod (12)
Is fixed to the inner shaft (9). Sleeve (10)
Around the protrusion (12A) of the rattling adjusting rod (12) between the rear end and the rattling prevention member (13), a stopper (1
A flange (second positioning member) (37) for abutting on the inner shaft (9) and restricting the forward position of the inner shaft (9) is attached thereto. On the front of the flange (37), an elastic shock-absorbing member (3
8) is installed. Also, between the detent nut (36) and the sleeve (10), around the protruding portion (12A) of the rattling adjustment rod (12), the stopper abuts on the stopper (17), and the inner shaft (9) A flange (second positioning member) (39) for restricting the retreat position is mounted. On the front surface of the flange (39), an impact absorbing member (40) made of an elastic material that absorbs an impact when the stopper (17) comes into contact is attached. That is, the flanges (37) and (39) sandwich the sleeve (10).
Detachable from the protruding part (12A) of the rod (12) to hold
It is fixed to.

At the rear end in the axial direction of the rattling preventing member (13), it fits in the tapered hole (19) of the inner shaft (9) and is formed around the tapered hole (19) and the fool hole (20). A push-spread portion (13a) that pushes the portion is formed. Push-out section (13
The peripheral surface of a) is a tapered spherical surface.

In the above-described configuration, when the head (12a) or the detent nut (36) of the rattling adjusting rod (12) is turned around the axis, the inner shaft (9) is inserted through the sleeve (10). ) The anti-rattle members (13) are pressed in the direction of approaching each other, and the push-out portions (13a) of the anti-rattle members (13)
Of the inner shaft (9) corresponds to the inner peripheral surface of the tapered hole (19) of the inner shaft (9). A plurality of slits (21) extending in the axial direction are formed around the tapered hole (19) and the fool hole (20) of the inner shaft (9).
The portion around the tapered hole (19) and the fool hole (20) is pushed radially outward by the push-out portion (13a) to open. As a result, the serrations (18) on the outer periphery of the inner shaft (9) are pressed against the serrations (14) on the inner periphery of the outer shaft (6), so that the engagement between these serrations is reduced. In this way, the outer shaft (6), the sleeve (10), and the inner shaft (9) are adjusted so that there is no play and that they slide smoothly in the axial direction.

The inner shaft (9) is formed by a serration (14) of the outer shaft (6) and the inner shaft (9).
(18) The outer shaft of the inner shaft (9) is supported by the meshing portion of the two and the anti-tilt collar (16).
(6) The inclination with respect to is prevented.

In the above-described electric telescopic steering apparatus, when performing a telescopic operation, the rotation of the telescopic motor (28) is reduced by the worm gear (34) and transmitted to the screw nut (31). The screw nut (31) rotates. Then, the rotation of the screw nut (31) is converted into an axial linear motion of the screw shaft (26). As a result, the front-rear direction of the force to the flange (23) acts, telescopic operation by moving back and forth the inner shaft (9) relative to the outer shaft (6) is carried out, you telescopic steering shaft (5) . When the flange (37) contacts the stopper (17), the advance position of the inner shaft (9) is restricted, and when the flange (39) contacts the stopper (17), the inner shaft (9) moves.
(9) The retreat position is regulated.

Here, it is necessary to change the length of the sleeve (10).
And the stroke amount of the steering shaft (5)
Can be changed easily and accurately.

In the above description, the peripheral surface of the push-spread portion (13a) of the rattling preventing member (13) is a spherical surface. However, the present invention is not limited to this. For example, the peripheral surface is a tapered conical surface. also not good.

FIG . 5 shows a modification of the anti-tilt collar. In FIG. 5, the inner shaft (9) of the anti-tilt collar (16)
(16a) and inner shaft
There is a gap (41) between the outer peripheral surface of (9) and the rear projecting portion (22a) integrally formed on the inner peripheral edge of the synthetic resin bush (22). It is fitted in.

[0027]

According to the electric telescopic steering device of the present invention, the relative position of the outer shaft and the inner shaft in the axial direction is regulated as described above.
Moreover, since the first and second positioning members are disposed inside the outer shaft, unlike the conventional case, no space is required for the positioning members outside the outer shaft. Therefore, the work of assembling the steering device into an automobile or the like is facilitated, and it is possible to prevent the steering device from being obstructed when arranging other devices. Furthermore, three
By changing the length of the
Can easily and accurately change the stroke amount
Therefore, the type of automobile to which the steering device is
As a result, the required steering shaft
Even when the troke amount changes, it can be easily handled.

Also, as described above, the front of the inner shaft
The end is hollow, and the inner peripheral surface of the hollow is
Tapered tapered section around the hollow
Multiple slits extending axially from the front end
After the sleeve and the second positioning member on the rear side.
The anti-rattle member is fitted around the shaft
The front end of the inner shaft is attached to the rear end of the
Fits into the hollow part of the
The push-spread portion is formed, and the backlash prevention member and inner
Hand that presses the shaft and the shaft in a direction approaching each other
With a step, the outer shaft spline and inner
Rattling at the point of engagement with the spline of the na shaft
The occurrence is prevented. Therefore, the steering shaft
The rigidity is improved, and rattling is prevented.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view showing a configuration of a main part of an electric telescopic steering device of the present invention.

FIG. 2 is a partially enlarged sectional view of a rear part of FIG. 1;

FIG. 3 is an enlarged sectional view of a front part of FIG.

FIG. 4 is an enlarged sectional view of a portion of the electric motor in FIG. 1;

FIG. 5 shows a modified example of the anti-tilt collar of the present invention.
It is a figure corresponding to a part of.

[Explanation of symbols]

 Reference Signs List 5 steering shaft 6 hollow outer shaft 9 hollow inner shaft 12A projecting portion (shaft portion) of rattling adjustment rod 14 serration 17 stopper (first positioning member) 18 serration 37 flange (second positioning member) 39 flange (second 2 positioning member)

Claims (2)

(57) [Scope of request for utility model registration] 1. A steering shaft comprising: a hollow outer shaft having a spline formed on an inner periphery; and an inner shaft having a spline formed on the outer periphery meshing with a spline of the outer shaft and inserted into the outer shaft. , an electric telescopic steering device steering shaft adapted to be caused to expand and contract by the rotation of the motor, the front end of the inner shaft, the shaft of diameter smaller than this front
Provided protruded and the stationary form, together with the first positioning member provided fixedly to the inner periphery of the outer shaft, the front and rear side portions of the first positioning member in the outer periphery of the shaft portion, a first positioning member, respectively A second positioning member that abuts and regulates the relative position of the outer shaft and the inner shaft in the axial direction is fixedly provided , and the two second positioning members fit around the shaft portion.
Detachably attaches to the shaft so that the sleeve is clamped
A fixed electric telescopic steering device. 2. The front end of the inner shaft has a hollow shape.
The inner peripheral surface of the hollow part tapered toward the rear
Tapered, from the front end to the part around the hollow part
A plurality of slits extending in the axial direction are formed,
And a shaft portion behind the second positioning member on the rear side.
The rattling prevention member is fitted around the
Into the hollow at the front end of the inner shaft.
The push-out part that pushes and spreads the part around the hollow part
The rattling prevention member and the inner shaft are
Claims comprising means for pressing in a direction approaching the axial direction
Item 2. An electric telescopic steering device according to Item 1.