JP2008024243A - Electric telescopic adjustment type steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric telescopic adjustment type steering device capable of absorbing the energy of an impact load without making the entire steering device disengaged from a vehicle body side member by a simple constitution. <P>SOLUTION: The electric telescopic adjustment type steering device comprises a column member 1 in which an inner column 1a and an outer column 1b for rotatably supporting a steering shaft 9 are fitted to each other in an expandable manner, and an electric actuator 51 having an output unit 57 movable in the axial direction by the drive of a motor 63 wherein the electric actuator 51 is fixed to any either the inner column 1a and the outer column 1b, and the output unit 57 of the electric actuator 51 is connected to the other. The positions in the axial direction of the inner column 1a and the outer column 1b can be adjusted by the drive of the motor 63, and when an impact load is inputted to the steering shaft 9, a coupling part of the output unit 57 of the electric actuator 51 with the other of the inner column 1a and the outer column 1b is relatively movable in the axial direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention has an electric telescopic adjustment having a column member in which an inner column and an outer column that rotatably support a steering shaft are telescopically fitted, and the inner column and the outer column are relatively moved by an electric actuator. The present invention relates to a type steering device.

As this type of electric telescopic adjustment type steering device, for example, a steering shaft connected to a steering wheel is rotatably supported on an inner column, and this inner column is telescopically fitted to an outer column to constitute a column member. There is known an electric steering column apparatus having a configuration in which an outer column is attached to a vehicle body side member via a column bracket, and an electric actuator for extending and retracting the inner column and the outer column is provided (for example, see Patent Document 1). .
International Publication WO 03/078334 Pamphlet (first page, FIG. 5, FIG. 11)

However, in the conventional example described in Patent Document 1, an electric actuator is attached between the inner column and the outer column. Therefore, when an impact load is transmitted to the steering shaft, the presence of the electric actuator causes the inner actuator to exist. There is an unsolved problem that the column cannot be contracted with respect to the outer column, the entire steering device needs to be detached from the vehicle body, and the layout of the steering device is restricted.
Therefore, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and can absorb energy of an impact load without separating the entire steering device from the vehicle body side member with a simple configuration. An object of the present invention is to provide an electric telescopic adjustment type steering device.

  In order to achieve the above object, an electric telescopic adjustment type steering apparatus according to claim 1 includes a column member in which an inner column and an outer column for rotatably supporting a steering shaft are fitted, and a drive of the electric motor. An electric actuator having an output section movable in the axial direction, and the electric actuator is fixed to one of the inner column and the outer column, and the output section of the electric actuator is coupled to the other to drive the electric motor In the electric telescopic adjustment type steering apparatus capable of adjusting the axial positions of the inner column and the outer column by means of an output of the electric actuator, the inner column, and the outer when an impact load is input to the steering shaft. Relative to the other side of the column in the axial direction It is characterized by being rotatably configured.

  According to a second aspect of the present invention, there is provided the electric telescopic adjustment type steering apparatus according to the first aspect, wherein the output portion is engaged with a coupling portion with the output portion of the electric actuator in the other of the inner column and the outer column. A long hole is formed, and when the impact load is input to the steering shaft, the output portion is configured to slide in the long hole.

  Furthermore, in the electric telescopic adjustment type steering apparatus according to a third aspect, in the invention according to the second aspect, the elongated hole has a normal engagement portion with which an output portion of the electric actuator is engaged in a normal state and an impact load is input. An impact load input engagement portion that engages with the output portion when the load is applied, protrudes inwardly between the normal engagement portion and the impact load input engagement portion, and It is characterized in that a protruding portion is formed on which the output portion can get over when inputting.

Furthermore, the electric telescopic adjustment type steering apparatus according to claim 4 is the invention according to claim 2 or 3, wherein the engagement portion at the time of impact load input gives a predetermined frictional resistance to the output portion. It is characterized by being formed.
Still further, the electric telescopic adjustment type steering apparatus according to claim 5 is the invention according to any one of claims 1 to 4, wherein the output portion of the electric actuator is coupled to the other of the inner column and the outer column. It is characterized by including a wire member that absorbs energy when the portion relatively moves in the axial direction.

According to the present invention, the connecting portion between the output portion of the electric actuator for relatively moving the inner column and the outer column of the column member and the other of the inner column and the outer column is configured to be relatively movable in the axial direction. With this configuration, when an impact load is input to the steering shaft, the coupling portion between the output part of the electric actuator and the other of the inner column and the outer column to which the output is connected is moved in the axial direction to absorb the impact load. In addition, since it is not necessary to separate the entire steering device from the vehicle body side member when the impact load is input, an effect that the degree of freedom in layout of the steering device can be improved is obtained.
In addition, when an impact load is input to the steering shaft, the frictional resistance is applied when the coupling portion between the output portion of the electric actuator and the other of the inner column and the outer column moves in the axial direction, so that the energy of the impact load is increased. The effect that absorption can be performed stably is acquired.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an overall configuration diagram of an electric telescopic adjustment type steering apparatus showing an embodiment of the present invention, FIG. 2 is a configuration diagram showing a specific configuration of an electric tilt adjustment mechanism, and FIG. 3 is a cross-sectional view taken along line AA in FIG. 4 is a cross-sectional view showing a connection structure between a ball stud and a sleeve of the electric tilt adjusting mechanism, FIG. 5 is a block diagram showing a specific configuration of the electric telescopic adjusting mechanism, and FIG. 6 is a bottom view showing the electric actuator of FIG. 7 is a bottom view in a state where the electric actuator of FIG. 6 is removed, FIG. 8 is a cross-sectional view taken along line BB of FIG. 6, and FIG. 9 is a cross-sectional view taken along line CC of FIG.

  In FIG. 1, an electric telescopic adjustment type steering device 16 extends in the front-rear direction of the vehicle, and supports a steering shaft 9 having a steering wheel 8 fixed to the rear side of the vehicle, rotatably inside a column member 1 supported by the vehicle body. is doing. The vehicle front side end portion of the steering shaft 9 is connected to an input shaft of the steering gear 19 through an intermediate shaft 18 having universal joints 17a and 17b at both ends so that steering torque can be transmitted.

Although not shown, the steering gear 19 includes a rack and pinion mechanism having a pinion connected to an input shaft and a rack shaft having a rack meshing with the pinion. The rack shaft is connected to a steered wheel (not shown) via a tie rod 20. Has been.
Then, by steering the steering wheel 8, steering torque is transmitted to the steering gear 19, and from the rack shaft serving as the output shaft to the steered wheel (not shown) via the tie rod 20, rotation of the steering wheel 8 is achieved. The steered wheels are steered according to the direction.

  As shown in FIG. 2, the column member 1 includes an inner column 1a that rotatably supports a steering shaft 9, and an outer column 1b in which the inner column 1a is telescopically fitted. The outer column 1b is supported by a column bracket 22 of a steel plate press-formed product fixed to the vehicle body side member 21. The column bracket 22 includes a mounting portion 23 that is fixed to the vehicle body side member 21, a pivot portion 24 that extends downward from the front end of the mounting portion 23, and a lower portion that extends downward from the rear end of the mounting portion 23. It is comprised from the column support plate part 25. FIG.

Here, in the pivot portion 24, a pivot pin 26 projecting from the column member 1 in a direction perpendicular to the axial direction is rotatably supported at the lower end portion, and the column member 1 is centered on the pivot pin 26. Is supported so as to be swingable in the vertical direction.
On the other hand, the column support plate portion 25 is formed in a rectangular plate shape as shown in FIG. 3, and the vehicle rear end side end portion of the outer column 1b constituting the column member 1 (see FIG. 2 is formed with a long hole 25a extending in the up-down direction for guiding the right end portion 2) to be movable up and down.

  An electric tilt adjusting mechanism 27 is provided for adjusting the tilt of the column member 1. As shown in FIG. 2, the electric tilt adjusting mechanism 27 includes a ball screw shaft support bracket 28 attached to the column member 1, a ball screw shaft 31 rotatably supported by the bracket 28, and the ball screw. A ball nut 32 screwed to the shaft 31 via a ball and an electric motor 38 that rotationally drives the ball screw shaft 31 are provided.

  The ball screw shaft support bracket 28 is integrally formed on one side in the width direction of the outer peripheral surface of the column member 1 (the front side in FIG. 2 and the left side in FIG. 3) substantially in parallel with the column support plate portion 25 of the column bracket 22. ing. The bracket 28 has a ball screw shaft 31 disposed between the upper and lower upper support portions 29 and the lower support portion 30, and both upper and lower end portions thereof are rotatably supported by rolling bearings (not shown).

  As shown in FIGS. 2 and 3, a ball nut 32 is screwed onto the ball screw shaft 31 with a ball interposed therebetween, and a ball portion 33 and a shaft portion 34 are formed on an end surface of the ball nut 32 on the vehicle rear side. A shaft portion 34 of the ball stud 35 is fixed. The ball portion 33 of the ball stud 35 is engaged in a cylindrical sleeve 36 that is formed at the same height position as the pivot shaft 26 on the rear end surface of the column support plate portion 25 of the column bracket 22, for example. . The mechanism for converting the rotational motion into the linear motion is not limited to the case where the above-described ball screw is applied, and a nut may be directly screwed onto the screw shaft.

As shown in FIG. 2, for example, a case body 39 having a rectangular cross section of the electric motor 38 is fixed to the ball screw shaft support bracket 28 so that the rotation shaft thereof is parallel to the axial direction of the column member 1. Yes.
The electric motor 38 is composed of, for example, a brushed DC motor, a brushless motor, or the like. As shown in FIG. 2, a worm 41 is connected to the rotary shaft 40, and the worm 41 is connected to the lower end side of the ball screw shaft 31 described above. It is meshed with the attached worm wheel 42.

  Therefore, when the electric motor 38 is driven forward / reversely, the ball screw shaft 31 is rotated forward / reversely via the worm 41 and the worm wheel 42, so that the ball stud 35 attached to the ball nut 32 supports the column of the column bracket 22. Since the column member 1 is engaged with the sleeve 36 fixed to the plate portion 25, the column member 1 can be rotated up and down around the pivot shaft 26 to perform tilt adjustment.

  When the column member 1 is tilt-adjusted, the column member 1 rotates about the pivot shaft 26. Therefore, the surface of the ball nut 32 to which the ball stud 35 is attached is connected to the pivot shaft 26 as shown in FIG. Since it extends in the tangential direction of each point on the center arc, when the ball nut 32 moves in the vertical direction with respect to the neutral position shown in the solid line, as shown in the two-dot chain line at the upper and lower end positions. The distance to the sleeve 36 changes with the inclination, but since the ball portion 33 of the ball stud 35 is engaged with the cylindrical sleeve 36, the inclination of the ball nut 32 and a change in the distance can be allowed. In addition, it is possible to prevent the tilt adjustment from being hindered and the occurrence of unnecessary stress and friction on each component member.

Further, the column member 1 is provided with an electric telescopic adjustment mechanism 50 as shown in FIG. The electric telescopic adjustment mechanism 50 includes an electric actuator 51 that expands and contracts the inner column 1a with respect to the outer column 1b.
As shown in FIGS. 5 and 6, an opening 52 that extends in the axial direction to expose the inner column 1a is formed at the lower end of the outer column 1b to which the electric actuator 51 is mounted. The outer peripheral surface at the lower end facing the opening 52 is a flat surface 53 as shown in FIG.

  The electric actuator 51 has ball screw shaft holding plate portions 54a and 54b that are integrally formed at both axial end positions of the opening 52 of the outer column 1b, and between these ball screw shaft holding plate portions 54a and 54b. Further, a ball screw shaft 55 rotatably held by a rolling bearing (not shown) is rotatably arranged. As with the electric tilt adjusting mechanism 27 described above, a worm wheel 56 is integrally attached to the ball screw shaft 55 on the front side of the vehicle (left end side in FIG. 8).

A ball nut 57 as an output portion is screwed onto the ball screw shaft 55 via a ball, and a ball stud 60 having a ball portion 58 and a shaft portion 59 is fixed to the ball nut 57, and the ball portion 58 is It is engaged with a cylindrical sleeve 62 that is engaged in a long hole 61 that is formed by extending in the axial direction on the outer peripheral surface exposed from the opening 52 of the inner column 1a. Also in this case, a screw shaft and a nut screwed to the screw shaft can be applied instead of the ball screw in the same manner as the electric tilt adjusting mechanism 27 described above.
On the other hand, an electric motor 63 is attached to the ball screw shaft holding plate portion 54a on the front side of the vehicle, and a worm 64 (which may be integrated with the rotating shaft or separate) may be formed on the rotating shaft. It is meshed with a worm wheel 56 attached to the screw shaft 55.

  Here, as shown in FIGS. 6 to 9, the long hole 61 formed in the inner column 1a includes a circular normal engagement portion 61a with which the sleeve 62 is normally engaged, and the normal engagement portion 61a. And an oval impact load input engagement portion 61b that engages with the sleeve 62 when an impact load is input to the inner column 1a. The normal engagement portion 61a When the impact load is input, the projecting portion protrudes inward from the opposite side wall between the engagement portion 61b and is collapsed by the sleeve 62 when an impact load greater than the set collapse load is input, or the sleeve 62 is a cylindrical spacer 62d described later. A protrusion 61c is formed that can contract and get over. Then, the width W of the engagement portion 61b at the time of impact load input is set narrow (φ> W) with respect to the diameter φ of the engagement portion 61a at the normal time to be a resistance applying portion, and the sleeve 62 is engaged at the time of impact load input. It is set so that the frictional energy is generated when the portion 61b is slid to absorb the impact energy stably.

  On the other hand, as shown in FIGS. 8 and 9, the sleeve 62 includes a bottomed cylindrical portion 62 a having an open lower surface with which the ball portion 58 of the ball stud 60 is engaged, and a center portion of the upper end surface of the bottomed cylindrical portion 62 a. A support shaft 62b protruding upward and having a male screw formed on the upper end side, a spacer 62c having a diameter wider than the width of the long hole 61 of the outer column 1b fitted on the support shaft 62b, and similarly supported on the spacer 62c. A cylindrical spacer 62d made of synthetic resin that is fitted on the shaft 62b and is slightly thicker than the inner column 1a and engages with the long hole 61, and a long hole in the inner column 1a that is screwed into the male screw of the support shaft 62b. 61, and a nut 62e having a diameter larger than that of the normal engagement portion 61a. Here, corner portions of the spacer 62c and the nut 62e that contact at least the outer peripheral surface and the inner peripheral surface of the inner column 1a are rounded.

  Then, the spacer 62c is first fitted on the support shaft 62b of the sleeve 62, and the cylindrical spacer 62d is fitted on the spacer 62c. Then, the normal engagement portion 61a of the elongated hole 61 of the inner column 1a is fitted. The nut 62e is inserted through the nut insertion hole 65 formed at a position opposed to the normal engagement portion 61a of the inner column 1a and the outer column 1b from above, and is screwed into the male screw of the support shaft 62b. As a result, the sleeve 62 is attached to the normal engagement portion 61a.

Next, the operation of the first embodiment will be described.
For example, when the driver is seated in the driver's seat and wants to adjust the tilt angle of the column member 1, for example, a tilt adjustment switch (not shown) that instructs up / down of the column member 1 disposed beside the column member 1. The tilt angle can be adjusted by driving the electric motor 38 of the electric tilt adjusting mechanism 27 forward and backward.
That is, when tilt up is selected with the tilt adjustment switch, the electric motor 38 of the electric tilt adjustment mechanism 27 is driven in reverse, for example, by a motor control device (not shown), whereby the ball screw shaft 31 is moved via the worm 41 and the worm wheel 42. By being reversed, the ball nut 32 moves toward the lower support portion 30 side of the ball screw shaft support bracket 28.

However, the ball nut 32 is engaged with the cylindrical sleeve 36 fixed to the column support plate portion 25 of the column bracket 22 fixed to the vehicle body side member 21 with the ball portion 33 of the ball stud 35 fixed thereto. Therefore, the ball nut 32 does not move up and down, but the ball screw shaft 31 moves upside down, and the column member 1 is pivoted through the ball screw shaft support bracket 28. With the pivot pin 26 as a fulcrum, it is guided to the long hole 25a of the column support plate portion 25 and tilted up.
When the column member 1 reaches the desired tilt up position, the tilt adjustment switch is returned to the OFF state, whereby the reverse rotation of the electric motor 38 is stopped and the column member 1 maintains the desired tilt up position. To do.

  Similarly, when the column member 1 is tilted down, tilt down is selected by a tilt adjustment switch (not shown), and the electric motor 38 is driven to rotate forward by a motor control device (not shown) to thereby drive the worm 41. The ball screw shaft 31 is driven to rotate forward via the worm wheel 42. Therefore, the column member 1 is guided by the long hole 25a of the column support plate portion 25 of the column bracket 22 and tilted down with the pivot pin 26 of the pivot portion 24 as a fulcrum. When the column member 1 reaches the desired tilt-down position, the tilt adjustment switch is turned off to stop the drive of the electric motor 38 and maintain the desired tilt-down position.

Thus, by driving the electric motor 38 forward and backward, the column member 1 can swing up and down about the pivot pin 26 to adjust the tilt position. The axial position and angle of the ball stud 35 fixed to the ball nut 32 with respect to the sleeve 36 change in accordance with the vertical swing.
However, since the ball portion 33 of the ball stud 35 is engaged with the sleeve 36, even if the axial position and angle of the ball stud 35 change, the ball portion 33 slides in the axial direction and the sliding contact is circumferential. By moving in the direction, the engagement relationship between the ball portion 33 and the sleeve 36 is not lost, and the tilting operation can be performed smoothly.

Further, when telescopic position adjustment for expanding / contracting the inner column 1a with respect to the outer column 1b of the column member 1 is desired, for example, a telescopic adjustment switch for instructing expansion / contraction of the telescopic position disposed on the side of the column member 1 By operating (not shown), the electric motor 63 of the electric telescopic adjustment mechanism 50 can be driven forward and backward to adjust the telescopic position.
That is, when extension is selected by the telescopic position adjustment switch, the electric motor 63 of the electric telescopic adjustment mechanism 50 is driven in reverse by a motor control device (not shown), whereby the ball screw shaft 55 is rotated in reverse via the worm 64 and the worm wheel 56. As a result, the ball nut 57 moves toward the ball screw shaft holding plate portion 54b.

  At this time, the ball portion 58 of the ball stud 60 attached to the ball nut 57 is engaged with the bottomed cylindrical portion 62a of the sleeve 62, and the sleeve 62 is normally engaged with the long hole 61 formed in the inner column 1a. Since the projecting portion 61c is engaged between the normal-time engaging portion 61a and the impact-load-input engaging portion 61b and cannot be normally passed, the sleeve 62 moves the projecting portion 61c in the normal time. Being engaged with the engaging portion 61b at the time of impact load input is prevented. As the ball nut 57 moves toward the steering wheel 8, the inner column 1a extends relative to the outer column 1b. When the inner column 1a reaches the desired telescopic extension position, the telescopic adjustment switch is returned to the OFF state, so that the reverse rotation of the electric motor 63 is stopped and the inner column 1a maintains the desired telescopic extension position. To do.

  Similarly, in order to contract the inner column 1a of the column member 1 with respect to the outer column 1b, telescopic contraction is selected by a telescopic adjustment switch (not shown), and the electric motor 63 is adjusted by a motor control device (not shown). By rolling and driving, the ball screw shaft 55 is driven to rotate forward via the worm 64 and the worm wheel 56. For this reason, the ball nut 57 is moved to the ball screw shaft holding plate portion 54a side, and the inner column 1a is contracted with respect to the outer column 1b accordingly. Then, when the inner column 1a reaches the desired telescopic contraction position, the telescopic adjustment switch is returned to the OFF state, whereby the forward drive of the electric motor 63 is stopped and the inner column 1a is set to the desired telescopic contraction position. Hold.

  Thus, when the telescopic position adjustment is performed by the electric telescopic adjustment mechanism 50, the sleeve 62 with which the ball portion 58 of the ball stud 60 attached to the ball nut 57 is engaged is formed in the inner column 1a. Since the protrusion 61c is formed between the elongated hole 61 and the normal engagement portion 61a of the long hole 61 and the engagement portion 61b when the impact load is input, the cylindrical shape of the sleeve 62 is used for normal telescopic position adjustment. The spacer 62d does not pass through the protrusion 61c, and the inner column 1a is expanded and contracted as the ball nut 57 moves.

However, if an impact load greater than the collapse load set in front of the vehicle acts on the steering wheel 8 during the secondary collision, the impact load can rotate the steering shaft 9 from the steering wheel 8 via the steering shaft 9. It is transmitted to the supporting inner column 1a.
The impact load transmitted to the inner column 1a at this time is equal to or greater than the collapse load, and the ball portion 58 of the ball stud 60 formed on the ball nut 57 is engaged with the bottomed cylindrical portion 62a of the sleeve 62, so that the shaft Since the movement in the direction is restricted, the protrusion between the normal engagement portion 61a and the impact load input engagement portion 61b in the long hole 61 formed in the inner column 1a by the impact load transmitted to the inner column 1a. 61c is crushed by the cylindrical spacer 62d of the sleeve 62 or the cylindrical spacer 62d is deformed, so that the normal-time engaging portion 61a of the long hole 61 is engaged with the cylindrical spacer 62d from the protruding portion 61c. Then, the state shifts to the state where the engaging portion 61b engages with the cylindrical spacer 62d when the impact load is input.

  For this reason, the inner column 1a contracts into the outer column 1b, and when the inner column 1a contracts, the width W of the engaging portion 61b at the time of impact load input is narrower than the diameter of the engaging portion 61a at the normal time. An appropriate frictional resistance is generated between the sleeve 62 and the cylindrical spacer 62d, so that the impact energy of the impact load transmitted to the steering wheel 8 can be stably absorbed.

Thus, according to the above-described embodiment, the ball portion 58 of the ball stud 60 attached to the ball nut 57 for positioning the telescopic position engages with the bottomed cylindrical portion 62a of the sleeve 62, and the cylindrical shape of the sleeve 62 is obtained. The spacer 62d is normally engaged with the normal engagement portion 61a of the long hole 61 formed in the inner column 1a. When an impact load greater than the collapse load is transmitted to the inner column 1a, the long hole The protruding portion 61c of 61 passes through the cylindrical spacer 62d of the sleeve 62, and the engaging portion 61b engages with the cylindrical spacer 62d of the sleeve 62 when an impact load is input. In this state, the cylindrical spacer 62d and the impact load are engaged. A frictional resistance is generated between the input engaging portion 61b and the impact energy of the impact load can be reliably absorbed.
Moreover, the impact energy can be absorbed and the entire steering apparatus can be separated by simply providing a long hole 61 formed in the inner column 1a and a sleeve 62 coupled to the ball nut 57 engaged therewith. Therefore, the degree of freedom in the layout of the steering device can be improved.

  In the above embodiment, the engagement portion 61b of the elongated hole 61 formed in the inner column 1a is set to have a width W smaller than the diameter φ of the normal engagement portion 61a so that the sleeve 62 has a cylindrical shape. The case where the frictional resistance is provided between the spacer 62d and the spacer 62d has been described. However, the present invention is not limited to this, and as shown in FIG. A synthetic resin material 70 is provided as a resistance imparting portion on the sliding contact surface with which the cylindrical spacer 62d of the sleeve 62b is in sliding contact, and a frictional resistance is generated between the sleeve 62 and the cylindrical spacer 62d. May be.

  Further, as shown in FIG. 11 showing a modified example of the long hole, the engagement portion 61b of the long hole 61 formed in the inner column 1a is set in the axial direction with the protruding portion 71 similar to the protruding portion 61c being set in the axial direction. A plurality of resistance imparting portions may be formed by arranging them at intervals, and a frictional resistance may be generated between the protruding portion 71 and the cylindrical spacer 62d of the sleeve 62 when an impact load is input.

  Further, as shown in FIG. 12 to FIG. 14 showing modifications of the long holes, the width W of the engaging portion 61b at the time of impact load input is formed to be equal to or larger than the diameter of the normal engaging portion 61a. The roller 72 is rotatably supported at the end opposite to the steering wheel 8 on the extended line of the long hole 61 of the inner column 1a with its axial direction orthogonal to the axial direction of the inner column 1a. A U-shaped portion 73a half-circulating the outer peripheral surface on the steering wheel 8 side of the bottomed cylindrical portion 62a, a parallel straight portion 73b reaching the roller 72 from both ends of the U-shaped portion 73a, and an end of the parallel straight portion 73b A bent portion 73c that is bent by 180 ° along the roller 72 and an extension portion 73d that extends from the bent portion 73c along the inner peripheral surface of the inner column 1a. Ya 73 may be disposed. In this case, when an impact load equal to or greater than the collapse load is input to the inner column 1a, the protrusion 61c in the long hole 61 of the inner column 1a passes through the cylindrical spacer 62d of the sleeve 62, and the impact load is input. When the inner column 1a contracts into the outer column 1b with the joining portion 61b engaging with the cylindrical spacer 62d of the sleeve 62, the bent portion 73c of the wire 73 is moved to the roller 72 as the inner column 1a contracts. A frictional resistance may be generated by squeezing at a position to absorb the impact energy of the impact load. Instead of the wire 73, a thin plate formed in the same shape as the wire 73 may be applied. The cross-sectional shape of the wire 73 is not limited to a round wire shape, and a cross-sectional shape may be an oval or polygonal shape, or a plate having a rectangular cross-section may be applied.

  Furthermore, in the above-described embodiment, the ball screw shaft 55, the electric motor 63, and the like constituting the electric actuator 51 are fixed to the outer column 1b, and the ball stud 60 attached to the ball nut 57 serving as the output portion of the electric actuator 51 is used. Although the case where the sleeve 62 with which the ball portion 58 engages is engaged with the long hole 61 provided in the coupling portion with the inner column 1a has been described, the present invention is not limited to this, and the electric actuator 51 is attached to the inner column 1a. A normal engagement portion 61a in which a ball screw 55 and an electric motor 63 are fixed, and a sleeve 62 that engages a ball portion 58 of a ball stud 60 attached to a ball nut 57 is formed in the outer column 1b. You may make it engage with the long hole 61 which has the hour engaging part 61b and the protrusion part 61c.

  Furthermore, in the above-described embodiment, the case where the sleeve 62 is engaged with the long hole 61 formed in the inner column 1a has been described. However, the present invention is not limited to this, and the sleeve 62 is fixed to the inner column 1a. The ball nut 57 is provided with a long hole corresponding to the long hole 61 having the normal engagement portion 61a, the impact load input engagement portion 61b, and the protruding portion 61c, and the shaft portion 59 of the ball stud 60 is described above in the long hole. You may make it engage by the structure similar to the sleeve 62. FIG.

  In the above embodiment, the case where the ball nut 57 is engaged with the elongated hole 61 of the inner column 1a via the ball stud 60 and the sleeve 62 has been described. However, the present invention is not limited to this. The sleeve 62 may be omitted, and instead of these, an engagement piece that directly engages with the elongated hole 61 of the inner column 1a may be formed on the ball nut 57. Also in this case, the engagement piece may be fixed to the inner column 1 a and the elongated hole 61 may be formed in the ball nut 57. Furthermore, the long hole 61 of the inner column 1a is omitted, the sleeve 62 is directly attached to the inner column 1a, and when the impact load at the time of the secondary collision is applied, the ball portion 58 of the ball stud 60 and the ball nut 57 You may comprise so that between may be fractured.

Furthermore, in the above-described embodiment, the case where the protruding portion 61c of the long hole 61 formed in the inner column 1a is protruded inward from each of the opposing side walls is not limited to this. You may make it protrude only from any one of these.
Furthermore, in the above embodiment, the case where the electric telescopic adjustment type steering device 16 has the electric tilt adjustment mechanism 27 has been described. However, the present invention is not limited to this, and the electric tilt adjustment mechanism 27 can be omitted. .

  Still further, in the above-described embodiment, the electric telescopic mechanism 50 is configured to be able to relatively move the coupling portion between the output portion of the electric actuator and the other of the inner column and the outer column when an impact load at the time of a secondary collision is input. However, the present invention is not limited to this, and the electric tilt mechanism 30 also has a long hole having a normal engagement portion 61a and an impact load input engagement portion 61b connected to the upper side of the column bracket 22. 61, and the sleeve 36 is engaged with the normal-time engaging portion 61a, so that when the impact load at the time of the secondary collision is applied to the steering wheel 8, the steering column 1 is moved upward by the vertical component force. When the sleeve 36 is moved, the sleeve 36 is detached from the normal engaging portion 61a and slides on the engaging portion 61b when an impact load is input. Ri, the impact energy by generating frictional resistance can be stably absorbed. Also in this case, similar to the electric telescopic mechanism 50, the modified examples shown in FIGS. Further, the long hole may be omitted and the ball portion 33 of the ball stud 35 and the ball nut 32 may be broken when an impact load is applied.

1 is an overall configuration diagram showing an electric telescopic adjustment type steering apparatus according to the present invention. It is a side view which shows an example of an electric tilt adjustment mechanism. It is the sectional view on the AA line of FIG. It is sectional drawing which shows the connection structure of the ball stud and sleeve of an electric tilt adjustment mechanism. It is a block diagram which shows the specific structure of an electric telescopic adjustment mechanism. It is a bottom view which shows the electric actuator of FIG. It is a bottom view of the state which removed the electric actuator of FIG. It is the BB sectional view taken on the line of FIG. It is CC sectional view taken on the line of FIG. It is a bottom view which shows the modification of the long hole formed in the inner column. It is a bottom view which shows the other modification of the long hole formed in the inner column. It is a bottom view which shows the further another modification of the long hole formed in the inner column. It is the DD sectional view taken on the line of FIG. It is the EE sectional view taken on the line of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Column member, 1a ... Inner column, 1b ... Outer column, 8 ... Steering wheel, 9 ... Steering shaft, 16 ... Electric telescopic adjustment type steering apparatus, 22 ... Column bracket, 24 ... Pivot part, 25 ... Column support part, 28 ... Ball screw shaft support bracket, 31 ... Ball screw shaft, 32 ... Ball nut, 33 ... Ball portion, 34 ... Shaft portion, 35 ... Ball stud, 36 ... Sleeve, 38 ... Electric motor, 41 ... Worm, 42 ... Worm wheel, 50 ... electric telescopic adjustment mechanism, 51 ... electric actuator, 52 ... opening, 55 ... ball screw shaft, 56 ... worm wheel, 57 ... ball nut, 58 ... ball portion, 59 ... shaft portion, 60 ... ball stud 61 ... Long hole, 61a ... Normal engagement portion, 61b ... Impact load input engagement portion, 61c ... Projection 62, sleeve, 62a ... bottomed cylindrical part, 62b ... support shaft, 62c ... spacer, 62d ... cylindrical spacer, 62e ... nut, 63 ... electric motor, 64 ... worm, 70 ... synthetic resin material, 71 ... Projection part 73 ... Wire 73a ... U-shaped part 73b ... Parallel straight part 73c ... Bending part 73d ... Extension part

Claims (5)

A column member in which an inner column and an outer column that rotatably support a steering shaft are telescopically fitted, an electric actuator having an output portion that is movable in an axial direction by driving of an electric motor, the inner column, and the outer column The electric actuator is fixed to one of the two, and the output portion of the electric actuator is coupled to the other, and the electric telescopic adjustment type steering capable of adjusting the axial position of the inner column and the outer column by driving the electric motor. In the device
When the impact load is input to the steering shaft, the electric actuator is configured such that the coupling portion between the output portion of the electric actuator and the other of the inner column and the outer column is relatively movable in the axial direction. Telescopic adjustable steering device.   When the other end of the inner column and the outer column is connected to the output portion of the electric actuator, a long hole is formed to engage the output portion, and when the impact load is input to the steering shaft, the output portion The electric telescopic adjustment type steering apparatus according to claim 1, wherein the electric telescopic adjustment steering apparatus is configured to slide in the elongated hole.   The elongated hole has a normal engagement portion with which the output portion of the electric actuator is normally engaged, and an impact load input engagement portion with which the output portion is engaged when an impact load is input, The protrusion part which protrudes inward between the said normal engagement part and the engagement part at the time of impact load input, and the said output part can get over when the said impact load is input is formed. 2. The electric telescopic adjustment type steering device according to 2.   4. The electric telescopic adjustment type steering apparatus according to claim 2, wherein the impact load input engagement portion is formed with a resistance applying portion that gives a predetermined frictional resistance to the output portion. 5.   The wire member which absorbs energy is provided when the connection part of the output part of the said electric actuator and the other of the said inner column and the other of the said outer column moves relatively in an axial direction. The electric telescopic adjustment type steering apparatus according to any one of the above.

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