JP2009101960A - Electrically-driven telescopic adjustment type steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrically-driven telescopic adjustment type steering device capable of stably absorbing impact from an initial stage to a final stage during a secondary collision with impact load applied to a steering wheel. <P>SOLUTION: A sliding contact holding member 60 is mounted in a plastically compressed state between a compression part 58e and an insertion part 58a. When the impact load is applied during the secondary collision, the sliding contact holding member 60 therefore slides on the compression part 58e, while being regulated in radial moving and rotation. Stable impact absorption load therefore is generated from starting of a collapse stroke to finishing of the stroke. Pre-load is imparted between a pre-load part 58d and the insertion part 58a in the sliding contact holding member 60 before plastically compressed between the compression part 58e and the insertion part 58a, and the sliding contact holding member 60 is mounted between the compression part 58e and the insertion part 58a without being rapidly plastically compressed. As a result, twisting due to local deformation of the sliding contact holding member 60 is prevented. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention includes an outer column and an inner column that are relatively telescopically connected, a steering column that rotatably supports a steering shaft to which a steering wheel is attached, one end portion of the outer column, and the other end The present invention relates to an electric telescopic adjustment type steering apparatus provided with an electric column actuator attached to the inner column and extending and contracting the outer column and the inner column.

Conventionally, an electric telescopic steering device has been proposed in which a shaft provided on a different axis from the steering column is driven in the axial direction by a motor to expand and contract a column connected to the shaft. As this electric telescopic steering device, for example, as described in Patent Document 1, a housing inner cylinder is slidably accommodated in a housing cylinder, and a steering shaft having a steering wheel at the tip is provided in the housing inner cylinder. The electric motor is attached to the housing cylinder, the mounting plate is attached to the inner cylinder of the housing, and a connecting rod is disposed between the electric motor and the mounting plate. The connecting rod is connected to the electric motor. It consists of a shaft that moves in the axial direction in conjunction with it, and an outer cylinder that is slidably inserted in the axial direction and that has a free end inserted into the mounting plate and tightened with a nut, and penetrates the shaft and the outer cylinder. One or more pins are press-fitted, and the pins are broken and collapsed by an impact force generated at the time of a collision or the like.
JP 2003-276616 A (first page, FIGS. 1 and 2)

  In the conventional example described in Patent Document 1, when a secondary collision load acts on the steering wheel, the secondary collision load acts on the outer cylinder of the connecting rod via the housing inner cylinder and the mounting plate. In this way, the pin that is press-fitted so as to penetrate the shaft and the inner cylinder can be broken and collapsed, but in order to absorb the impact at the time of the secondary collision, the pin is broken at the time of collapse. The relative movement between the shaft and the outer cylinder needs to be performed while applying a predetermined load, and the load during the relative movement needs to be stabilized in order to perform stable shock absorption.

However, when the pin is ruptured at the time of the secondary collision, the shock absorption between the collapse strokes after the pin rupture depends on the sliding contact resistance between the shaft and the outer cylinder. Stable shock absorption cannot be performed until the end.
Therefore, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and can stably absorb shock from the initial stage to the final stage at the time of a secondary collision in which an impact load acts on the steering wheel. 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 has an outer column and an inner column which are relatively telescopically connected, and a steering shaft to which a steering wheel is attached is rotatable. A steering column to be supported; and an electric actuator having one end attached to the outer column and the other end attached to the inner column, and contracting the outer column and the inner column. An electric telescopic adjustment type steering device having a contraction part that contracts in the axial direction while absorbing a shock load while generating a predetermined load in the axial direction when an impact load at the time of collision is input, wherein the contraction part is A rod, an insertion portion through which the rod is inserted, and an opposing surface of the rod and the insertion portion. The sliding contact holding member is formed on one of the opposing surfaces of the rod and the insertion portion, and the sliding contact holding member to which a predetermined pressing force is applied from the other opposing surface is compressed and disposed. A compression portion that connects and holds the insertion portion, and an end portion of one opposing surface continuous to the compression portion, and the sliding contact holding member compresses the compression portion when the sliding contact holding member is disposed in the compression portion. And a preload portion that applies preload so as to be compressed with a lower pressing force than the portion.

  According to a second aspect of the present invention, in the electric telescopic adjustment type steering apparatus according to the first aspect, the preload portion is formed at an end portion of the rod, and the sliding portion is formed between the inner peripheral surface of the insertion portion. A small diameter portion set to an outer diameter compressed by the contact holding member, wherein the compression portion is formed continuously with the small diameter portion, and the sliding contact holding member compresses between the inner peripheral surface of the insertion portion A large-diameter portion set to have a larger outer diameter than the small-diameter portion.

According to a third aspect of the present invention, in the electric telescopic adjustment type steering apparatus according to the second aspect, the diameter gradually increases between the small diameter portion and the large diameter portion from the small diameter portion toward the large diameter portion. The taper part which becomes large was formed.
According to a fourth aspect of the present invention, in the electric telescopic adjustment type steering apparatus according to the second or third aspect, an axial length of the small diameter portion is greater than or equal to an axial length of the sliding contact holding member. Is set.

  According to a fifth aspect of the present invention, in the electric telescopic adjustment type steering apparatus according to the first aspect, the preload portion is formed at an end portion of the insertion portion, and the sliding contact with an outer peripheral surface of the rod. A large-diameter inner peripheral surface set to an inner diameter compressed by the holding member, the compression portion is formed continuously with the large-diameter inner peripheral surface, and the sliding contact holding member is between the outer peripheral surface of the rod and It is a small diameter inner peripheral surface set to the inner diameter to be compressed.

According to a sixth aspect of the present invention, in the electric telescopic adjustment type steering apparatus according to the fifth aspect, the large-diameter inner diameter portion is directed to the small-diameter large-diameter portion between the large-diameter inner diameter portion and the small-diameter inner diameter portion. In accordance with this, a tapered portion having a gradually decreasing diameter was formed.
According to a seventh aspect of the present invention, in the electric telescopic adjustment type steering apparatus according to any one of the first to sixth aspects, the sliding contact holding member has a crest and a trough on the front and back surfaces in the circumferential direction. It is the corrugated cylindrical member which protrudes alternately and continues.

  Furthermore, the invention according to claim 8 is the electric telescopic adjustment type steering apparatus according to any one of claims 1 to 7, wherein the compression portion compresses the sliding contact holding member in a plastic region, and the preload portion Is configured to compress the sliding contact holding member in an elastic region.

  According to the electric telescopic adjustment type steering device of the present invention, since the sliding contact holding member is mounted in a compressed state between the compression portion formed on one of the rod and the insertion portion and the other, the secondary collision When an impact load is sometimes applied, the sliding contact holding member slides on the compression portion while restricting radial movement and rotation. Therefore, it is possible to generate an impact absorbing load from the start to the end of the collapse stroke.

  Furthermore, the sliding contact holding member before being subjected to plastic compression between the compression portion and the other of the rod and the insertion portion is preloaded between the preload portion and the other of the rod and the insertion portion, Therefore, the sliding contact holding member can be prevented from being twisted due to local deformation, and a stable shock absorbing load can be generated.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an overall configuration diagram showing a vehicle equipped with an electric telescopic adjustment type steering device according to the present invention, FIG. 2 is an overall configuration diagram of an electric telescopic adjustment type steering device according to the present invention, and FIG. 4 is a cross-sectional view taken along the line BB in FIG. 3, FIG. 5 is a cross-sectional view of the main part of the present invention, FIG. 6 is a cross-sectional view taken along the line CC in FIG. 5 is a cross-sectional view similar to FIG. 5, FIG. 8 is a view showing a sliding contact holding member, FIG. 8 (a) is a side view, and FIG. 8 (b) is a cross-sectional view taken along the line CC in FIG. FIG. 8 (c) is an enlarged view of the F portion of FIG. 8 (b), FIG. 9 is a longitudinal sectional view showing the contraction portion, and FIG. 10 is a preload at the small diameter portion before the sliding contact holding member is arranged on the large diameter portion 11 is an enlarged cross-sectional view taken along the line H-H in FIG. 9, FIG. 12 is an enlarged view of a portion G in FIG. 10, and FIG. 13 shows a relationship between compression and load of the sliding contact holding member. It is a characteristic diagram.

  In FIG. 1, a steering column device 10 includes a steering column 12 that supports a steering shaft 11 so as to be rotatable. A steering wheel 13 is mounted at the rear end of the steering shaft 11, and an intermediate shaft 15 is connected to the front end of the steering shaft 11 via a universal joint 14. A steering gear 17 composed of a rack and pinion mechanism or the like is connected to the intermediate shaft 15 through a universal joint 16 at the front end thereof. The output shaft of the steering gear 17 is connected to the steering wheel 19 via a tie rod 18.

When the driver steers the steering wheel 13, the rotational force is transmitted to the steering gear 17 via the steering shaft 11, the universal joint 14, the intermediate shaft 15, and the universal joint 16, and the rack and pinion mechanism rotates the vehicle. The steering wheel 19 is steered through the tie rod 18 after being converted into a linear motion in the width direction.
In addition, peripheral parts P such as a control switch, a combination switch, a column cover, and the like for driving an electric tilt mechanism 30 and an electric telescopic mechanism 50 described later are disposed at a rear portion of the steering column 12 in the vehicle.

  As shown in FIG. 5, the steering column device 10 is disposed so as to be inclined backward by a predetermined angle θ with respect to the horizontal direction of the vehicle. As shown in FIG. 5, the steering column device 10 includes an outer shaft 11a to which a steering wheel 13 is attached as shown in FIG. 5, and an inner shaft 11b that is slidably engaged with the outer shaft 11a by spline coupling or serration coupling. It consists of and.

  2 and 5, the steering column 12 includes an outer column 12a and an inner column 12b that is slidably held by the outer column 12a. The outer shaft 11a of the steering shaft 11 is rotatably supported by a rolling bearing 12f disposed on the surface and a rolling bearing (not shown) disposed on the inner peripheral surface of the vehicle front side.

  The outer column 12a has a rear end (left end in FIG. 2) on the side of the universal joint 14 supported by a lower bracket 22 attached to the vehicle body side member 21 so as to be swingable in the vertical direction by a pivot pin 23. A front end (right end in FIG. 2) is attached to the vehicle body side member 21 and is supported by the upper bracket 24 so as to be movable in the vertical direction.

As shown in FIG. 3, the upper bracket 24 includes a mounting plate portion 24b having a bulging portion 24a with a central portion bulging upward attached to the vehicle body side member 21, and a bulging portion of the mounting plate portion 24b. The guide plate portions 24c and 24d extending downward from the left and right positions of 24a and the bottom plate portion 24e connecting the lower ends of the guide plate portions 24c and 24d are formed in a rectangular frame shape.
The outer column 12a described above is inserted into the guide space 24f surrounded by the mounting plate portion 24b, the guide plate portions 24c and 24d, and the bottom plate portion 24e of the upper bracket 24. As is apparent from FIG. 3, the outer column 12a has a protruding portion that protrudes in the horizontal direction, and its end portion has guide plate portions 12d and 12e each having a vertical guide surface 12c that is closely opposed to the guide plate portions 24c and 24d. Is formed.

  The guide plate portion 12e is held by the electric tilt mechanism 30 so as to be movable in the vertical direction. As shown in FIG. 3, the electric tilt mechanism 30 is a rolling bearing 33 fixedly arranged by a restraining member 32 in a substantially rectangular frame-shaped gear housing 31 formed integrally with the lower end portion of the guide plate portion 24 d of the upper bracket 24. And a screw shaft 35 that extends in the vertical direction along the guide plate portion 24d and is rotatably supported by the rolling bearing 34 disposed on the lower surface of the mounting plate portion 24b of the upper bracket 24 described above.

  A worm wheel 36 is mounted on the screw shaft 35 in the vicinity of the rolling bearings 38 a and 38 b in the gear housing 31, and a worm 37 is engaged with the worm wheel 36. As shown in FIG. 4, the worm 37 is rotatably held by rolling bearings 38 and 39 disposed in the gear housing 31, and one end of the worm 37 is attached to the guide plate portion 24 d of the upper bracket 24. The output shaft 40a of the electric motor 40 fixed to the plate portion 24g is connected via a coupling 40b.

  A cylindrical cover 42 that covers the screw shaft 35 is disposed in an insertion hole 31 a through which the screw shaft 35 of the gear housing 31 is inserted, and a large elasticity that slides on the outer peripheral surface of the screw shaft 35 at the tip of the cylindrical cover 42. A damper 43a made of a synthetic resin such as polyurethane having Similarly, a damper 43 b that is in sliding contact with the outer peripheral surface of the screw shaft 35 is disposed on the lower end surface of the rolling bearing 34.

  A nut 45 held by a nut holder 44 having a square cross section is screwed between the dampers 43 a and 43 b of the screw shaft 35. The nut holder 44 engages in a guide groove 46 formed in the guide plate portion 24d of the upper bracket 24 and extending in the vertical direction, so that the rotational movement around the axis of the screw shaft 35 of the nut holder 44 is restricted. The nut holder 44 is moved in the vertical direction by forward and reverse rotation of the screw shaft 35. An engaging pin 47 protruding from the nut holder 44 is engaged with a long hole 24h extending in the axial direction of the outer column 12a formed at the tip of the outer column 12a.

Therefore, when the worm 37 is driven forward / reversely by the electric motor 40, the screw shaft 35 is driven forward / reversely via the worm wheel 36, whereby the nut holder 44 is moved up and down, and the outer column 12a is centered on the pivot pin 23. As a result, the tilt function can be exerted.
An electric telescopic mechanism 50 as an electric actuator is provided between the outer column 12a and the inner column 12b of the steering column 12 as shown in FIG.

  As shown in FIG. 5, the electric telescopic mechanism 50 includes a gear housing 51 fixed to the steering wheel 13 side of the outer column 12 a of the steering column 12. A worm wheel 54 is rotatably supported on the gear housing 51 by rolling bearings 52 and 53 that are arranged to face each other at a predetermined distance in the axial direction of the steering column 12. The worm wheel 54 is formed in a cylindrical shape having a large-diameter outer peripheral surface at the center and small-diameter outer peripheral surfaces fitted with rolling bearings 52 and 53 on both ends sandwiching the large-diameter outer peripheral surface. In addition, a helical gear 54a is formed, and a female screw 54b is formed on the inner peripheral surface.

  As shown in FIG. 6, the worm 56 connected to the output shaft of the electric motor 55 attached to the gear housing 51 is engaged with the helical gear 54 a of the worm wheel 54. Here, the worm 56 is rotatably supported by rolling bearings 56a and 56b disposed in the gear housing 51, and is connected to the output shaft 55a of the electric motor 55 via a coupling 55b. The worm wheel 54 and the worm 56 constitute a speed reducer. Further, a linear motion mechanism is constituted by a connecting rod 58 described later and a female screw 54b of the worm wheel 54.

  On the other hand, as shown in FIG. 5, a connecting plate 57 that extends in the same direction as the gear housing 51 at a position closer to the steering wheel 13 of the inner column 12b of the steering column 12 and is spaced from the end surface of the outer column 12a. A connecting rod 58 is disposed between the connecting plate 57 and the gear housing 51 while maintaining a predetermined offset L from the central axis of the steering column 12.

The connecting rod 58 includes an outer rod 58a having one end attached to the lower end of the connecting plate 57, and an inner rod 58b slidably inserted into the other end of the outer rod 58a. 59.
The inner rod 58b is formed with a male screw 58f on the side opposite to the outer rod 58a. The male screw 58f is screwed into a female screw 54b of a worm wheel 54 rotatably supported by the gear housing 51, thereby connecting rod 58b. Is arranged so as to be parallel to the axial direction of the steering column 12.

Therefore, by driving the electric motor 55 forward / reversely, driving the worm wheel 54 forward / reversely via the worm 56, and moving the inner rod 58 b back and forth in the axial direction of the steering column 12, the outer rod 58 a and the connection The inner column 12b is driven to extend and contract in the axial direction via the plate 57 to exhibit a telescopic function.
The contracting portion 59 described above regulates the relative movement between the outer rod 58a and the inner rod 58b depending on the joint between the outer rod 58a and the inner rod 58b and a normal driver or the like. When an excessive impact load is transmitted to the outer rod 58a via the steering wheel 13, the inner column 12b, and the connecting plate 57, the sliding contact holding member 60 that allows relative movement between the outer rod 58a and the inner rod 58b is configured.

As shown in FIG. 8, the sliding contact holding member 60 is an end ring made of a corrugated thin leaf spring material in which crests 60a and troughs 60b alternately protrude from the front and back surfaces in the circumferential direction. The peak portion 60a and the valley portion 60b are long in the axial direction.
In the normal molding, as shown in FIG. 8C, the sliding contact holding member 60 is not formed into a perfect circle due to the radial displacement Y between the end portions 60c and 60d even in a free state. Has a twist during molding.

Further, as shown in FIGS. 9 to 12, an annular housing recess 58c is formed on the inner peripheral surface of the outer rod 58a, and a sliding contact holding member 60 is mounted between the housing recess 58c and the inner rod 58b. Has been.
The outer peripheral surface of the inner rod 58b, as shown in FIG. 10, a small diameter portion 58d of the diameter phi _A formed on the distal end side, larger diameter than the diameter of the small diameter portion 58d formed on the vehicle front side of the small-diameter portion 58d a large diameter portion 58e of phi _B is formed. Here, the diameter φ _A of the small diameter portion 58d is set to the same dimension as the designed inner diameter dimension of the sliding contact holding member 60 (the inner diameter dimension of the perfectly circular sliding contact holding member 60).

Between the small diameter portion 58d and the large diameter portion 58e, a tapered portion 58f having a diameter gradually increasing from the small diameter portion 58d toward the large diameter portion 58e is formed.
The axial length L1 of the small diameter portion 58d is set to be longer than the axial length L2 of the peak portion 60a and the valley portion 60b of the sliding contact holding member 60 that contacts the small diameter portion 58d.
The sliding contact holding member 60 which is not in a perfect circle shape in a free state and is disposed in the accommodating recess 58c of the outer rod 58a is disposed on the outer periphery of the small diameter portion 58d of the inner rod 58b, and then passes through the tapered portion 58f. Is mounted on the outer periphery of the large-diameter portion 58e.

  At this time, the sliding contact holding member 60 is formed in a perfect circle shape by eliminating the radial displacement of the both end portions 60c and 60d, and is disposed on the outer peripheral surface of the small diameter portion 58d of the inner rod 58b while the radial movement and rotation are restricted. As shown in FIG. 13, it is attached between the small-diameter portion 58d and the accommodating recess 58c in an elastically compressed state by contacting the inner peripheral surface of the annular accommodating recess 58c and pressing radially inward. At this time, all the crests 60a of the sliding contact holding member 60 are in contact with the outer peripheral surface of the inner rod 58b, and all of the troughs 60b are also in contact with the inner peripheral surface of the housing recess 58c.

Then, the sliding contact holding member 60 that has passed through the taper portion 58f has a uniform contact pressure with respect to the outer peripheral surface of the large diameter portion 58e, with its entire circumference being uniform, and as shown in FIG. Is attached to the outer peripheral surface of the large-diameter portion 58e. Thus, in the outer rod 58a and removing load (collapse load) to permit relative movement of the inner rod 58b F _L of the sliding holding member 60 which is mounted on the outer peripheral surface of the large diameter portion 58e is a state of being plastically compressed, for example, about It is set to 2 kN or more. Note that the sliding contact holding member 60 of the present embodiment may be attached to the outer peripheral surface of the large diameter portion 58e in an elastically compressed state as long as a predetermined collapse load is set.

Here, the preload portion of the present invention corresponds to the small diameter portion 58d, and the compression portion of the present invention corresponds to the large diameter portion 58e.
Next, the operation of the apparatus of the above embodiment will be described.
Now, in order for the driver to adjust the tilt of the steering column 12 of the steering column device 10, the control for the tilt mechanism provided in the peripheral part P provided in the rear part of the steering column 12 shown in FIG. When the switch is operated in the tilt-up direction (or tilt-down direction), the electric motor 40 of the electric tilt mechanism 30 is driven forward (or reverse), for example.

  In response to this, by driving the screw shaft 35 in reverse (or forward) via the worm 37 via the worm 37, the nut 45 moves upward (or downward) as viewed in FIG. Since the engaging pin 47 formed on the nut holder 44 is engaged with the long hole 24h formed on the outer column 12a of the steering column 12, the outer column 12a rotates upward (downward) about the pivot pin 23. And tilt up (or tilt down) adjustment.

  In addition, in order for the driver to perform telescopic adjustment of the steering column 12 of the steering column device 10, a control for a telescopic mechanism provided in a peripheral part P disposed in the vehicle rear portion of the steering column 12 shown in FIG. When the switch is operated in the expansion direction (or contraction direction), the electric motor 55 of the electric telescopic mechanism 50 is driven forward (or reverse), for example.

  As a result, the worm wheel 54 is driven to rotate forward (or reversely) via the worm 56, whereby the inner rod 58b of the connecting rod 58 moves to the steering wheel 13 side (or the side opposite to the steering wheel 13) and slides. The outer rod 58a moves to the steering wheel 13 side (or the side opposite to the steering wheel 13) via the contact holding member 60.

For this reason, the inner column 12b is pulled out from the outer column 12a via the connecting plate 57 (or the inner column 12b is inserted into the outer column 12a), and the steering column 12 is expanded (or contracted) to perform telescopic adjustment. be able to.
At this time, along with the movement of the inner column 12b, the outer shaft 11a of the steering shaft 11 moves relative to the inner shaft 11b.

  Thus, the electric telescopic mechanism 50 can telescopically adjust the telescopic column 12 by expanding and contracting. At this time, at the normal time when the connecting rod 58 is moved by the electric motor 55, the sliding contact holding member 60 is slidably contacted with the small diameter portion 58d of the inner rod 58b while the contact pressure is high. For this reason, expansion / contraction between the outer rod 58a and the inner rod 58b is reliably prevented, and the outer rod 58a and the inner rod 58b integrally move the connecting plate 57 in the vehicle front-rear direction and move the inner column 12b in the vehicle front-rear direction. be able to.

  On the other hand, when an impact load F that presses the steering wheel 13 toward the front side of the vehicle in the horizontal direction of the vehicle, that is, the left side in FIG. 5, is applied to the steering wheel 13 due to the secondary collision. It is divided into a perpendicular component Fy. Then, the inner column 12b and the outer shaft 11a are pushed to the left in the column axial direction as viewed in FIG. 5 by the column axial component force Fx, and the outer rod 58a of the connecting rod 58 is moved to the left via the connecting plate 57 accordingly. The axial force component Fx is transmitted to the sliding contact holding member 60 by being moved.

Then, the column axial component force Fx is transmitted to the sliding holding member 60 exceeds the collapse load F _L which is set, sliding retaining member 60 allows the relative movement of the outer rod 58a and the inner rod 58b Then, the inner rod 58b is inserted into the outer rod 58a to ensure a predetermined collapse stroke.
Here, immediately before the column axial load Fx exceeds collapse load F _L is sliding retaining member 60 is mounted in a state of being plastically compressed between the housing recess 58c and the large diameter portion 58e, all crests 60a All the valley portions 60b are in contact with the outer peripheral surface of the large-diameter portion 58e, and all the valley portions 60b are in contact with the inner peripheral surface of the housing recess 58c, so that the radial movement and rotation of the sliding contact holding member 60 are restricted.

Then, at the beginning of the collapse stroke (when the column axial load Fx exceeds the collapse load F _L), sliding retaining member 60 that is mounted in a state of being plastically compressed sliding the outer peripheral surface of the large diameter portion 58e The shock absorption load _FEA is generated by moving.
Therefore, according to this embodiment, the column axial load Fx acts on the constriction 59 during a secondary collision, when the collapse stroke starts beyond the collapse load F _L, between the large diameter portion 58e and the housing recess 58c in mounted in a state of being plastically compressed, since sliding retaining member 60 radial movement and rotation is regulated slides on the outer peripheral surface of the large diameter portion 58e, generating a shock absorbing load F _EA until the collapse stroke ends can do.

The sliding contact holding member 60 mounted between the large diameter portion 58e and the housing recess 58c is elastically compressed between the small diameter portion 58d and the housing recess 58c. since mounted without, since entanglement by local deformation of the sliding retention member 60 can be prevented, it is possible to generate a stable impact absorption load F _EA from the start to the end of the collapse stroke.

Further, when the sliding contact holding member 60 is mounted from the small diameter portion 58d to the large diameter portion 58e, the sliding contact holding member 60 is in sliding contact with the tapered portion 58f formed between the small diameter portion 58d and the large diameter portion 58e. Since the plastic compression of the sliding contact holding member 60 is gradually performed, the sliding contact holding member 60 can be further prevented from being twisted.
Further, when the sliding contact holding member 60 is elastically compressed and mounted between the small diameter portion 58d and the housing recess 58c, as shown in FIG. 10, the axial length L1 of the small diameter portion 58d is equal to the sliding contact holding member 60. Longer than the axial length L2, all the crests 60a of the sliding contact holding member 60 are in contact with the outer peripheral surface of the small diameter portion 58d, and all the troughs 60b are also in contact with the inner peripheral surface of the accommodating recess 58c. Therefore, local deformation of the sliding contact holding member 60 at the time of mounting on the large diameter portion 58e can be reliably prevented.

In the present embodiment, the case where one tapered portion 58f is provided between the small diameter portion 58d and the large diameter portion 58e of the inner rod 58b has been described. However, the present invention is not limited to this, and two or more tapered portions are provided. May be provided.
Further, in the present embodiment, setting the diameter phi _A of the inner rod 58b in inner diameter and the same size on the design of the sliding holding member 60, sliding contact between the inner circumferential surface of the annular housing recess 58c If the holding member 60 is elastically compressed, a different diameter φ _A may be set.

Further, the axial length L1 of the small diameter portion 58d of the inner rod 58b may be equal to or longer than the axial length L2 of the sliding contact holding member 60.
In the present embodiment, the annular housing recess 58c is formed on the inner peripheral surface of the outer rod 58a, and the small diameter portion 58d and the large diameter portion 58e are formed on the inner rod 58b. A peripheral surface and a small-diameter inner peripheral surface may be formed, and an annular housing recess may be formed on the outer periphery of the inner rod.

Further, in this embodiment, the outer rod 58a is located at the rear of the vehicle and the inner rod 58b is located at the front of the vehicle and is connected to each other so as to be stretchable. However, the outer rod 58a is located at the front of the vehicle, and the inner rod 58b is You may make it couple | bond together so that it may be located back and can expand and contract.
In this embodiment, the case where the outer rod 58a of the connecting rod 58 is directly fixed to the connecting plate 57 has been described. However, the present invention is not limited to this, and the outer rod 58a of the connecting rod and the connecting plate 57 are connected to the pivot pin. You may make it connect via. In this case, when the column axial component force Fx is applied to the inner column 12b, it is possible to reliably prevent the bending moment that twists the connecting rod 58 generated in the connecting plate 57 from affecting the connecting rod 58. When the column axial component force Fx becomes equal to or greater than the collapse load, the relative movement of the connecting rod 58 between the outer rod 58a and the inner rod 58b can be further stabilized, and better shock absorption can be performed. .

Furthermore, in the present embodiment, the case where the outer column 12a of the steering column 12 is fixed to the vehicle body side member 21 has been described. However, the present invention is not limited to this, and the inner column 12b is formed by the lower bracket 22 and the upper bracket 24. The steering wheel 13 may be attached to the vehicle body side member 21 and the outer column 12a side.
Furthermore, in the present embodiment, the case where the electric tilt mechanism 30 is provided has been described. However, the present invention is not limited to this, and the electric tilt mechanism 30 is omitted and only the electric telescopic mechanism 50 is provided. May be.

1 is an overall configuration diagram showing a vehicle in which an electric telescopic adjustment type steering apparatus according to the present invention is assembled. 1 is an overall configuration diagram of an electric telescopic adjustment type steering apparatus according to the present invention. It is sectional drawing on the AA line of FIG. It is sectional drawing on the BB line of FIG. It is sectional drawing of the principal part of this invention. It is sectional drawing on the CC line of FIG. It is sectional drawing similar to FIG. 5 which shows a contracted state. It is a figure which shows a sliding contact holding member, (a) is a side view, (b) is sectional drawing on CC line of (a), (c) is the F section enlarged view of (b). It is a longitudinal cross-sectional view of the contraction | shrinking part which shows the state which has given the preload by the small diameter part, before arrange | positioning a sliding contact holding member in a large diameter part. It is a figure which shows the state which has given the preload by the small diameter part, before arrange | positioning a sliding contact holding member in a large diameter part. It is an expanded sectional view on the HH line of FIG. It is the G section enlarged view of FIG. It is a characteristic diagram which shows the relationship between the compression of a sliding contact holding member, and a load.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Steering column apparatus, 11 ... Steering shaft, 11a ... Outer shaft, 11b ... Inner shaft, 12 ... Steering column, 12a ... Outer column, 12b ... Inner column, 12c ... Guide surface, 12d, 12e ... Guide plate part, 12e DESCRIPTION OF SYMBOLS ... Guide plate part, 12f ... Bearing, 13 ... Steering wheel, 14 ... Universal joint, 15 ... Intermediate shaft, 16 ... Universal joint, 17 ... Steering gear, 18 ... Tie rod, 19 ... Steering wheel, 21 ... Car body side member, 22 ... lower bracket, 23 ... pivot pin, 24 ... upper bracket, 24a ... bulge, 24b ... mounting plate, 24c, 24d ... guide plate, 24e ... bottom plate, 24f ... guide space, 24g ... mounting plate, 24h ... long hole, 30 ... electric tilt mechanism, 31 ... gear housing 31a ... insertion hole, 32 ... member, 33 ... rolling bearing, 34 ... rolling bearing, 35 ... screw shaft, 36 ... worm wheel, 37 ... worm, 38 ... rolling bearing, 38a, 38b ... rolling bearing, 40 ... electric motor, 40a ... output shaft, 40b ... coupling, 42 ... cylindrical cover, 43a ... damper, 43b ... damper, 44 ... nut holder, 45 ... nut, 46 ... guide groove, 47 ... engagement pin, 50 ... electric telescopic mechanism, DESCRIPTION OF SYMBOLS 51 ... Gear housing, 52 ... Rolling bearing, 54 ... Worm wheel, 54a ... Helical gear, 54b ... Male screw, 55 ... Electric motor, 55a ... Output shaft, 55b ... Coupling, 56 ... Worm, 56a ... Rolling bearing, 57 ... Connection Plate, 58 ... Connecting rod, 58a ... Outer rod, 58b ... Inner rod, 58c ... Housing recess, 58d ... Small Parts, 58e ... large-diameter portion, 58f ... taper portion, 59 ... constriction, 60 ... sliding holding member, 60a ... peak portion, 60b ... valleys, 60c, 60d ... the end, F _EA ... impact absorption load, F _L ... Collapse load, Fx ... Column axial component

Claims (8)

A steering column that has an outer column and an inner column that are relatively telescopically connected, and that rotatably supports a steering shaft to which a steering wheel is attached, one end of the steering column and the other end An electric actuator attached to the inner column and contracting the outer column and the inner column, and the electric actuator generates a predetermined load in an axial direction when an impact load at the time of a secondary collision is input. An electric telescopic adjustment type steering device having a contraction part that contracts in the axial direction and absorbs an impact load,
The contraction portion is formed on a rod, an insertion portion for inserting the rod, a sliding contact holding member disposed between opposing surfaces of the rod and the insertion portion, and one opposing surface of the rod and the insertion portion. A compressing portion that compresses and arranges the sliding contact holding member to which a predetermined pressing force is applied from the other facing surface, and connects and holds the rod and the insertion portion, and one facing the compressing portion. A preloading portion that is formed at an end of a surface and applies a preload so that the sliding contact holding member compresses with a pressing force lower than that of the compression portion when the sliding contact holding member is disposed in the compression portion. An electric telescopic adjustment type steering device characterized by that. The preload portion is a small-diameter portion formed at an end of the rod and set to an outer diameter compressed by the sliding contact holding member between the inner peripheral surface of the insertion portion,
The compression portion is a large-diameter portion that is formed continuously with the small-diameter portion and has a larger outer diameter than the small-diameter portion that is compressed by the sliding contact holding member with the inner peripheral surface of the insertion portion. The electric telescopic adjustment type steering apparatus according to claim 1.   3. The electric telescopic adjustment type steering apparatus according to claim 2, wherein a taper portion whose diameter gradually increases from the small diameter portion toward the large diameter portion is formed between the small diameter portion and the large diameter portion. .   4. The electric telescopic adjustment type steering apparatus according to claim 2, wherein an axial length of the small diameter portion is set to be equal to or longer than an axial length of the sliding contact holding member. The preload portion is a large-diameter inner peripheral surface that is formed at an end portion of the insertion portion and is set to an inner diameter that the sliding contact holding member compresses between the rod and the outer peripheral surface.
The compression portion is a small-diameter inner peripheral surface that is formed continuously with the large-diameter inner peripheral surface and is set to an inner diameter that the sliding contact holding member compresses between the rod and the outer peripheral surface. The electric telescopic adjustment type steering apparatus according to claim 1.   6. The electric motor according to claim 5, wherein a tapered portion is formed between the large-diameter inner diameter portion and the small-diameter inner diameter portion so that the diameter gradually decreases from the large-diameter inner diameter portion toward the small-diameter large-diameter portion. Telescopic adjustable steering device.   The slidable contact holding member is a corrugated cylindrical member in which crests and troughs protrude alternately on the front and back surfaces in the circumferential direction and are continuous. The electric telescopic adjustment type steering apparatus as described.   The said compression part compresses the said sliding contact holding member in a plastic region, The said precompression part compresses the said sliding contact holding member in an elastic region, The any one of Claim 1 thru | or 7 characterized by the above-mentioned. The electric telescopic adjustment type steering apparatus as described.

Images