JP5158475B2 - Steering column device - Google Patents

Description

  The present invention relates to a steering column device that transmits a rotational force of a steering wheel to a steering device.

  The steering column device is an important safety and security component of the vehicle, and it is very important how to control the behavior at the time of the collision in order to ensure the safety of the passenger at the time of the collision. Normally, the steering column device itself is provided with an impact energy absorbing mechanism, and also plays an important role as a support member for an air bag accommodated in the steering wheel.

  Conventionally, various impact energy absorption mechanisms have been proposed. Most of them focus on how to absorb the energy at the time of collision, but when mounted on a real vehicle, the steering shaft is fixed with high rigidity during normal operation, and the specified energy is absorbed quickly at the time of collision. It is necessary to do. Accordingly, the driver can increase the drive feeling by operating the steering wheel supported with high rigidity, and the impact received by the driver at the time of collision can be effectively reduced. However, since these two characteristics are usually contradictory, it is difficult to achieve both, and if the steering shaft is fixed with high rigidity, the energy absorption mechanism becomes difficult to operate at the time of a collision, or an extra resistance acts to absorb energy. It becomes unstable. On the other hand, if the energy absorbing action is to be performed stably and reliably, the support of the steering shaft is loosened and the rigidity is lowered. As a result, the drive feeling may deteriorate.

More specifically, the problems of the prior art will be described. In Patent Document 1, a pair of column tightening fixing portions are disposed on the vehicle front side of a pair of flat plate-like support wall portions, so that a vehicle body mounting bracket support wall portion and a column tightening fixing portion are arranged in a secondary collision. A steering column device is disclosed in which the movement start direction is substantially horizontal and the movement start can be performed stably.
JP 2004-161021 A

  However, according to the technique of Patent Document 1, the movement of the steering column is started when the tilt pivot bolt that fixes the steering column to the vehicle body at the lower end is pulled out forward. Accordingly, in order to increase the support rigidity of the steering column, it is sufficient to increase the tightening force of the tilt pivot bolt, but this delays the timing of starting the movement of the steering column at the time of the secondary collision. On the other hand, if the tightening force of the tilt pivot bolt is reduced in order to speed up the movement of the steering column at the time of the secondary collision, the support rigidity of the steering column is thereby lowered.

  On the other hand, a technique has been developed in which the steering column is fixed to the skid bracket, and the skid bracket is held by a predetermined holding means, thereby adjusting the timing of starting the movement of the steering column at the time of the secondary collision. However, in such a configuration, the amount of movement of the skid bracket is limited, so that a large amount of energy must be absorbed with a short stroke, and there is a problem that adjustment of the holding means is difficult.

  The present invention has been made in view of the problems of the prior art, and an object of the present invention is to provide a steering column device capable of changing energy absorption characteristics in a limited space.

The steering column device of the present invention is a steering column device that holds a steering shaft with respect to a vehicle body.
A steering column for holding the steering shaft;
A top member movable relative to the steering column;
A bracket attached to the vehicle body and holding the steering column;
A clamp shaft that passes through the bracket, the top member, and the steering column;
Pressing means for applying an axial force to the clamp shaft and pressing the bracket against the steering column and the top member;
When the steering shaft receives an external force in the axial direction, the steering column and the top member can be independently displaced relative to the bracket .
When the steering shaft receives an external force in the axial direction, after the steering column is displaced relative to the bracket, the coma member starts to displace, thereby gradually displacing the energy absorption amount,
The top member is arranged to be displaceable along a groove formed in the steering column .

  According to the steering column device of the present invention, when the steering shaft receives an external force in the axial direction, the steering column and the top member can be independently displaced relative to the bracket. By selecting the material and dimensions of the top member, it is possible to adjust the amount of energy absorbed when the top member is displaced with respect to the steering column, thereby absorbing energy even when placed in a limited space. The characteristics can be easily adjusted.

  When the steering shaft receives an external force in the axial direction, it is preferable that the top member starts to be displaced after the steering column is displaced with respect to the bracket.

  It is preferable that the top member is disposed so as to be displaceable along a groove formed in the steering column.

  It is preferable to provide suppression means for suppressing relative displacement between the steering column and the top member.

  A tilt / telescopic steering device according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of the steering column device according to the present embodiment. FIG. 2 is a view of the configuration of FIG. 1 taken along the line II-II and viewed in the direction of the arrow. FIG. 3 is a perspective view of the column according to the present embodiment. FIG. 4 is a view of the configuration of FIG. 3 taken along the line IV-IV and viewed in the direction of the arrow. In the present specification, the “telescopic direction” refers to the direction of the approximate axis of the steering shaft, and the “tilt direction” refers to the direction (particularly the vertical direction) intersecting it.

  In FIG. 2, a bracket 1 attached to a vehicle body VB (FIG. 1) supports a column (steering column) 3 as described later. An upper shaft 5 that is connected to the steering wheel 4 and transmits the steering force to the pinion shaft PS of the rack and pinion mechanism that is a steering mechanism is inserted into the column 3 and is rotatably supported by a bearing (not shown). Has been.

  In FIG. 1, the lower end of the upper shaft 5 is attached to the upper end of the lower shaft 8 so as to be displaceable in the axial direction and integrally rotate. The upper shaft 5 and the lower shaft 8 constitute a steering shaft. The lower shaft 8 is rotatably supported by a bearing 13 held in a cylindrical pivot bracket 12 pivotally attached to a pivot support point PV fixed to the vehicle body VB.

  A lower end of the lower shaft 8 is connected to an upper end of the intermediate shaft 10 via a universal joint portion 9 disposed in the vicinity of a bulkhead BH that separates the vehicle compartment from the engine room. The lower end of the intermediate shaft 10 is connected to the pinion shaft PS via the universal joint portion 11. The pinion of the pinion shaft PS is meshed with a rack shaft (not shown), and the wheel is steered via a steering mechanism (not shown) by converting the rotation of the pinion shaft PS into the axial movement of the rack shaft. It has become.

  In FIG. 2, the bracket 1 attached to the vehicle body has side plates 1a and 1a extending in parallel in the vertical direction. Tilt long holes 1b and 1b extending in the tilt direction are formed in the side plates 1a and 1a, respectively. A column 3 is arranged between the side plates 1a and 1a.

  The hollow column 3 has a guide groove 3a extending in the telescopic direction on the left side surface, and further telescopically extending in the telescopic direction so as to penetrate sideways within the guide groove 3a. A long hole 3b is formed.

  As shown in FIG. 3, a rectangular parallelepiped frame member 20 is disposed in the guide groove 3a so as to be movable along the guide groove 3a. The top member 20 forms a long hole 20a that overlaps the telescopic long hole 3b. At the time of fixing, the left side plate 1 a abuts both the side surface of the column 3 and the side surface of the top member 20.

  As shown in FIG. 2, the clamp bolt 15 which is a clamp shaft includes an operation lever 6, a cam mechanism 7, a tilt long hole 1b of the left side plate 1a, a long hole 20a of the top member 20, a telescopic long hole 3b, and a right side plate. The tilt elongated hole 1b of 1a and the needle bearing 19 are inserted in the horizontal direction in this order and screwed into the nut 18.

  The cam mechanism 7 that constitutes the pressing means includes a follower portion 7a that is attached to the operation lever 6 and rotates integrally, and a cam portion 7b that engages with the tilted long hole 1b of the bracket 1 and is not relatively rotatable. Have The cam portion 7b and the follower portion 7a have irregularities in the circumferential direction, and when this is relatively rotated, the axial distance between the cam portion 7b and the follower portion 7a changes according to the rotational position. It has become.

  Next, the operation of the present embodiment will be described. When tilting or telescopic adjustment is performed, in FIG. 2, when the operator turns the operation lever 6 in a predetermined direction, the cam portion 7 b and the follower portion 7 a of the cam mechanism 7 are relatively rotated to approach each other. It is displaced to. Thereby, since the axial force of the clamp bolt 15 is lost, the side plates 1a and 1a of the bracket 1 are not biased from both sides, so that the frictional force acting between the side plates 1a and 1a and the column 3 and the piece member 20 is reduced. Decrease or disappear. Therefore, the operator applies a force to the steering wheel 4 to rotate the column 3 around the pivot support point PV within the range in which the clamp bolt 15 moves within the tilt long hole 1b. The steering wheel 4 can be displaced to the tilt position, and the column 3 together with the upper shaft 5 can be displaced in the axial direction within a range in which the clamp bolt 15 moves in the long hole 20a of the top member 20. Thus, the steering wheel 4 can be displaced to an arbitrary telescopic position.

  When the tilt or telescopic adjustment is completed, in FIG. 1, the operator turns the operation lever 6 in the reverse direction, whereby the cam portion 7 b and the follower portion 7 a of the cam mechanism 7 are relatively rotated and separated from each other. It is displaced to. At this time, the left side plate 1a that has received the axial force via the cam mechanism 7 by the axial force generated in the clamp bolt 15 has the left side surface of the column 3 with the piece member 20 interposed therebetween. The right side plate 1a that receives the axial force through the needle bearing 19 presses the right side surface of the column 3 to generate the frictional force. As a result, the frictional force acting between the bracket 1, the piece member 20, and the column 3 is firmly fixed to each other.

  When the steering wheel 4 is rotated in this state, the rotational motion is transmitted to the pinion shaft PS via the upper shaft 5, the lower shaft 8, the universal joint portion 9, the intermediate shaft 10, and the universal joint portion 11, and the The wheels are steered at a necessary angle by being converted into the axial movement of the rack shaft by the illustrated rack and pinion mechanism.

  By the way, when the driver's body is thrown forward and collides with the steering wheel 4 during a vehicle collision, a so-called secondary collision occurs. At this time, if the steering wheel 4 moves forward while absorbing the impact, the driver can be protected. When the steering column device according to the present embodiment is fixed, the left side plate 1a presses the left side surface of the column 3 with the piece member 20 sandwiched therebetween to generate a predetermined frictional force. When a secondary collision occurs, in addition to relative sliding between the bracket 1 and the column 3, relative sliding between the bracket 1 and the top member 20 and relative sliding between the column 3 and the top member 20 can be caused. Therefore, even if the total length of the column 3 is short, impact energy can be efficiently converted into heat and absorbed by friction.

  FIG. 5 is a diagram showing a change with time of the steering column device at the time of the secondary collision. The clamp bolt 15 is assumed to be at an arbitrary position in the long hole 20a of the top member 20. At the time of the secondary collision, as shown in FIG. 5 (a), when an axial force is input to the steering shaft 5, the column 3 is pushed forward (to the left in FIG. 5) via a bearing (not shown). . At this time, referring to FIG. 2, the right side plate 1 a slides with respect to the side surface of the column 3, but the left side plate 1 a slides with respect to the side surface of the top member 20.

  When the column 3 moves from the initial position by the distance Δ1, the clamp bolt 15 hits the end of the long hole 20a of the top member 20 (see FIG. 5B). Thereafter, upon receiving a reaction force from the clamp bolt 15, the top member 20 starts to move relative to the guide groove 3a. Eventually, when the column 3 moves from the initial position by a distance Δ2, the piece member 20 is locked to the end of the guide groove 3a, and the movement of the column 3 is completed.

  FIG. 6 is a graph comparing energy absorption characteristics of the steering column device of the comparative example and the steering column device of the present embodiment. In the comparative example, the top member is not provided, and the side plate of the bracket is in direct contact with the side surface of the column.

  In FIG. 6, as indicated by the dotted line B, the energy absorption amount of the steering column of the comparative example suddenly increases from the time of the secondary collision and becomes constant thereafter. On the other hand, in this embodiment, the frictional force generated between the side plate 1a and the side surface of the piece member 20 is lower than the frictional force generated between the side plate 1a and the side surface of the column 3. As indicated by the solid line A, relatively low energy absorption is performed while the column 3 moves from the initial position by the distance Δ1 from the time of the secondary collision, and then the absorbed energy is increased. In this way, the driver can be further protected by absorbing energy in two stages.

  FIG. 7 is a perspective view similar to FIG. 3 of a steering column device according to a modification of the present embodiment. In this modification, the piece member 120 has a hole 120a that fits into the clamp bolt 15 (FIG. 2). Accordingly, since the bracket 1 does not move relative to the top member 120 at the time of the secondary collision, the energy absorption amount is constant regardless of the movement amount of the column 3. According to this modification, the frictional force generated between the side plate 1a and the side surface of the piece member 120 is changed to the side plate 1a by changing the piece member 120 to a desired material (including a material whose surface treatment is changed). And the frictional force generated between the column 3 and the side surface of the column 3 can be made higher or lower. Therefore, the energy absorption characteristic of the steering column device can be easily changed by selecting an appropriate material according to the application.

  By the way, depending on the steering column device, in the event of a secondary collision, an airbag or the like provided on the steering wheel may be deployed to protect the driver. In such a steering column device, it is desired to maintain the direction of the steering wheel at the time of a secondary collision in order to make the best use of the effect of the airbag. A steering column device optimal for such applications will be described below.

  FIG. 8 is an exploded view of a steering column device according to another embodiment. FIG. 9 is a perspective view of the lock member as viewed from the side opposite to FIG. In the present embodiment, the top member 220 has vertical teeth 220b formed on the side surface around the long hole 220a. On the left side plate 201a of the bracket 201, lateral teeth 201c are formed on the side surfaces on both sides of the tilt long hole 201b. The lock member 230 having a rectangular plate shape has vertical teeth 230a formed at the center of the thickest plate, and a through hole 230b formed at the center of the vertical teeth 230a. On both sides of the vertical teeth 230a, the plate thickness is thinner than the center, and horizontal teeth 230c and 230c are formed alongside the vertical teeth 230a. The ends of the wave springs 230d and 230d are riveted to both ends where the plate thickness is the thinnest. The lock member 230 constitutes a suppression means.

  The clamp bolt 15 includes an operation lever 6 (see FIG. 2), a cam mechanism 7 (see FIG. 2), a hole 230b in the lock member 230, a tilt long hole 201b in the left side plate 201a, a long hole 220a in the top member 220, and a telescopic length. The hole 3b, the tilted long hole 201b of the right side plate 201a, and the needle bearing 19 (see FIG. 2) are inserted in the horizontal direction and screwed into the nut 18 (see FIG. 2). In the assembled state, the vertical teeth 230a of the lock member 230 enter the tilt elongated hole 201b and face the vertical teeth 220b of the top member 220, and the horizontal teeth 230c of the lock member 230 face the horizontal teeth 201c of the bracket 201, respectively. The wave springs 230d are in contact with the surface of the side plate 201a.

  In a state where the clamp bolt 15 is tightened using the operation lever, the lock member 230 is urged toward the top member 220 while the wave spring 230d is elastically deformed by the axial force generated in the clamp bolt 15, and the vertical teeth 230a are The horizontal teeth 230c mesh with the vertical teeth 220b of the top member 220, and the horizontal teeth 230c mesh with the horizontal teeth 201c of the bracket 201, respectively. In other words, the clamp bolt 15 is securely fixed in the tilt direction with respect to the bracket 1 and in the telescopic direction with respect to the top member 20 via the lock member 230, so that a strong force is applied during the secondary collision. However, the direction of the steering wheel attached to the column 3 can be made unchanged. At this time, since the column 3 can move to the front side of the vehicle within the range in which the top member 220 moves in the guide groove 3a, the impact energy can be absorbed thereby. In order to strengthen tightening between the bracket 201 and the column 3, for example, the engagement between the vertical teeth 230a of the lock member 230 and the vertical teeth 220b of the top member 220 eliminates backlash, and the horizontal teeth 230c and the bracket 201 It is desirable that the meshing with the lateral teeth 201c is slightly loose.

  On the other hand, when the clamp bolt 15 is loosened using the operation lever, the axial force of the clamp bolt 15 disappears, so that the lock member 230 is biased away from the side plate 201a of the bracket 1 by the elastic force of the wave spring 230d. Thus, the vertical teeth 230a are detached from the vertical teeth 220b of the top member 220, and the horizontal teeth 230c are separated from the horizontal teeth 201c of the bracket 201, respectively. That is, since the restraint of the clamp bolt 15 due to the engagement is released, the tilt or telescopic adjustment can be performed against the frictional force acting between the bracket 201 and the column 3.

  FIG. 10 is a view showing the periphery of a top member of a steering column device according to a modified example. In the present modification, three through holes 3c are formed from the upper part of the column 3 toward the guide groove 3a, and on the upper surface of the piece member 220, bag holes 220d corresponding to the through holes 3c are respectively formed. Is formed. The resin R is filled and solidified from the through hole 3c to the bag hole 220d. Resin R constitutes a suppression means.

  According to this modified example, when the piece member 220 starts to move with respect to the guide groove 3a at the time of the secondary collision, the solidified resin R shears, and thus, when the piece member 220 starts to move, You can determine the power. Note that the force at the start of movement of the top member 220 can be adjusted to a desired value by appropriately selecting the cross-sectional area of the through hole 3c and the bag hole 220d and the type of the resin R.

  FIG. 11 is a view showing the periphery of a top member of a steering column device according to a modified example. In this modification, an elastic member 240 molded from rubber or resin is disposed between the end of the guide groove 3a and the piece member 220. In the state before the secondary collision, as shown in FIG. 11A, the elastic member 240 is in a free state, but when the piece member 220 starts moving with respect to the guide groove 3a in the secondary collision, As shown in FIG. 11 (b), the elastic member 240 is compressed and deformed, and the elastic deformation force is used to provide resistance to the movement of the top member 220, so that the amount of energy absorption can be further increased. The elastic member 240 constitutes a suppression means.

  FIG. 12 is a view showing the periphery of a top member of a steering column device according to a modified example. In this modified example, as shown in FIG. 12A, a notch 220e having a narrow end-side inlet and a wide back is formed on the back surface of the piece member 220. On the other hand, the wire member 250 has an end portion 250a that is short and bent into a hairpin shape, an arc portion 250b that follows the end portion 250a, and a linear portion 250c that follows the end portion 250a.

  The wire member 250 is attached by fitting the end portion 250a into the notch 220e. At this time, as shown in FIG. 12B, the wire member 250 is mounted in the narrow groove 3f formed on the side surface of the column 3 and having the radius portion 3e having the radius R while maintaining the shape. When the top member 220 starts to move with respect to the guide groove 3a at the time of the secondary collision, the wire member 250 is dragged and moves in the narrow groove 3a as shown in FIG. When the squeezed wire member 250 is plastically flowed, resistance can be given to the movement of the piece member 220, and thus the amount of energy absorption can be further increased. The wire member 250 constitutes suppression means.

  FIG. 13 is a view showing the periphery of a top member of a steering column device according to another modification. An arm 6a is formed on the operation lever 6 ', and a gear portion 6b having gear teeth on both sides is formed on the end thereof. On the other hand, a receiving portion 3g is formed on the side surface of the column 3 ', and receiving teeth 3h arranged in two rows are formed on the upper surface of the receiving portion 3g.

  When the operation lever 6 'is rotated in the tightening direction, the arm 6a rotates together with it, and the gear teeth of the gear portion 6b mesh with the receiving teeth 3h of the receiving portion 3g. Is fixed in the telescopic direction. On the other hand, when the operation lever 6 ′ is rotated in the loosening direction, the arm 6a is rotated together with it, and the gear teeth of the gear portion 6b are detached from the receiving teeth 3h of the receiving portion 3g. The column 3 can be arbitrarily moved and desired telescopic adjustment can be performed. The arm 6a and the receiving part 3h constitute a suppression means.

  As described above, the present invention has been described in detail with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and can be appropriately changed and improved without departing from the spirit thereof. Of course there is. For example, it is optional to combine the steering column device of the present invention with another shock absorbing mechanism.

It is a side view of the steering column apparatus which concerns on this Embodiment. It is the figure which cut | disconnected the structure of FIG. 1 by the II-II line | wire, and looked at the arrow direction. It is a perspective view of the column concerning this Embodiment. It is the figure which cut | disconnected the structure of FIG. 3 by the arrow IV-IV line, and looked at the arrow direction. It is a figure which shows the time-dependent change of the steering column apparatus at the time of a secondary collision. It is the graph which compared the steering column apparatus of the comparative example, and the steering column apparatus energy absorption characteristic of this Embodiment. It is a perspective view similar to FIG. 3 of the steering column apparatus concerning the modification of this Embodiment. It is an exploded view of the steering column apparatus concerning another embodiment. It is the perspective view which looked at the locking member from the opposite side to FIG. It is a figure which shows the periphery of the top member of the steering column apparatus concerning a modification. It is a figure which shows the periphery of the top member of the steering column apparatus concerning a modification. It is a figure which shows the periphery of the top member of the steering column apparatus concerning a modification. It is a figure which shows the periphery of the top member of the steering column apparatus concerning another modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bracket 1a Side plate 1b Tilt long hole 3, 3 'column 3a Guide groove 3b Telesco long hole 3c Through-hole 3e Scratch part 3f Narrow groove 3g Receiving part 3h Receiving tooth 4 Steering wheel 5 Upper shaft 6, 6' Operation lever 6a Arm 6b Gear part 7 Cam mechanism 7a Follower part 7b Cam part 8 Lower shaft 9 Universal joint part 10 Intermediate shaft 11 Universal joint part 12 Pivot bracket 13 Bearing 15 Clamp bolt 18 Nut 19 Needle bearing 20 Top member 20a Long hole 120 Top member 120a Hole 201 Bracket 201a Side plate 201b Tilt long hole 201c Lateral tooth 220 Top member 220a Long hole 220b Vertical tooth 220d Bag hole 220e Notch 230 Lock member 230a Vertical tooth 230b Hole 230b Through hole 230 c Lateral teeth 240 Elastic member 250 Wire member 250a End portion 250b Arc portion 250c Linear portion BH Bulkhead PS Pinion shaft PS Pinion shaft PV Pivot support point R Resin VB Car body

Claims (2)

In the steering column device that holds the steering shaft with respect to the vehicle body,
A steering column for holding the steering shaft;
A top member movable relative to the steering column;
A bracket attached to the vehicle body and holding the steering column;
A clamp shaft that passes through the bracket, the top member, and the steering column;
Pressing means for applying an axial force to the clamp shaft and pressing the bracket against the steering column and the top member;
When the steering shaft receives an external force in the axial direction, the steering column and the top member can be independently displaced relative to the bracket .
When the steering shaft receives an external force in the axial direction, after the steering column is displaced relative to the bracket, the coma member starts to displace, thereby gradually displacing the energy absorption amount,
The steering column device, wherein the top member is disposed so as to be displaceable along a groove formed in the steering column. The steering column apparatus according to claim 1 , further comprising a suppression unit that suppresses relative displacement between the steering column and the top member.

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