JP2001260900A - Energy absorbing steering column device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost, size and weight by using energy absorbing members which are inexpensive to manufacture and easy to mount without considering interference with other members. SOLUTION: Base portions 12, 12 of energy absorbing members 10, 10 formed by bending metal wire materials into U-shape are locked to the front edge of a steering column 1. Bent portions 15, 15 provided on energy absorbing portions 13, 13 of the energy absorbing members are arranged in shear passages 14, 14 provided in a shearing member 11. The shearing member 11 which is prevented from being displaced frontward by a front supporting bracket 9 is axially movable with respect to the steering column 1. During secondary collision, the shearing member 11 displaces the bent portions 15, 15 to the rear end of the energy absorbing portions 13, 13 to absorb impact energy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION An impact-absorbing steering column apparatus according to the present invention displaces a steering wheel forward in a secondary collision so that a large impact is not applied to a driver's body.

[0002]

2. Description of the Related Art When a vehicle collides, a so-called secondary collision occurs in which a driver collides with a steering wheel, following a so-called primary collision in which the vehicle collides with another vehicle or the like. For the purpose of reducing the impact received by the driver in the event of this secondary collision and protecting the life of the driver, the steering shaft that fixes the steering wheel at one end, the overall length shrinks when a strong impact is applied, It is common practice to use a so-called collapsible steering shaft and a shock absorbing type steering column through which the steering shaft is inserted.

Conventionally, a shock absorbing type steering column device used for such a purpose is disclosed in, for example,
-272448, 11-1165643,
Japanese Patent Application Laid-Open No. 11-268655 is known. In each of these hitherto known shock absorbing steering column devices, the steering column is supported on the vehicle body so as to be freely displaceable forward based on a strong forward impact force, and a portion fixed to the vehicle body and a steering column are fixed. And a shock absorbing member is provided between the two. When an impact force that pushes the steering column forward due to a secondary collision caused by a collision is applied, the steering column is allowed to be displaced forward while the energy absorbing member is plastically deformed to extend in the front-rear direction. Then, based on the plastic deformation of the energy absorbing member, the impact energy transmitted from the steering wheel to the steering column is absorbed, and the impact force applied to the driver's body during a secondary collision is reduced, thereby protecting the driver. Can be achieved.

[0004]

In the case of the conventional structures described in the above publications, the shape of the components is complicated and the cost increases, or it is difficult to secure a space for arranging the components. There are problems such as difficulty in reducing the size and weight. In view of such circumstances, the present invention provides a shock-absorbing steering column in which the shape of each component is simple, can be manufactured at low cost, and a space for arranging each component can be easily secured, and the size and weight can be reduced. It was invented to realize the device.

[0005]

According to the shock absorbing type steering column apparatus of the present invention, similarly to the conventionally known shock absorbing type steering column apparatus, the steering column is moved forward relative to the vehicle body with respect to the vehicle body. When a strong impact load is applied to the steering column, it is supported so that it can drop forward, and between the portion fixed to the vehicle body and the steering column, the energy that acts as a resistance against displacement of the steering column forward. An absorbing member is provided.

Particularly, in the shock absorbing type steering column device of the present invention, the energy absorbing member is formed by bending a metal wire, and a front end of the energy absorbing member is locked to a front end of the steering column. Things. A handle member having a handle passage bent in the axial direction of the steering column is fitted inside the steering column near the front end of the steering column so as to be displaceable in the axial direction of the steering column. The handling member is supported by the vehicle body in a state where forward displacement is prevented. Further, a part of the metal wire constituting the energy absorbing member is inserted through the handling passage from the front to the rear.

[0007]

The operation of the shock absorbing steering apparatus of the present invention having the above-described structure is as follows. At the time of a secondary collision, a forward-facing load is applied to the steering column from the steering wheel via the steering shaft. This load causes the energy absorbing member to be displaced forward together with the steering column. On the other hand, the handle member is not displaced forward while being supported by the vehicle body, but is displaced relative to the steering column toward the rear end side of the steering column. Therefore, a part of the metal wire constituting the energy absorbing member is handled in the handling passage of the handling member. More specifically, a part of the metal wire bent in accordance with the shape of the handling passage moves from the originally formed portion toward the rear end of the metal wire.

As described above, the energy absorbing member is plastically deformed so as to move the bent portion toward the rear end of the metal wire. The applied impact energy is absorbed. As a result, the impact applied to the driver's body is reduced, and the driver is protected during a secondary collision.

[0009]

1 to 6 show a first embodiment of the present invention. The steering column 1 is moved forward (see FIGS. 1, 2, 4, 6) via a steering wheel (not shown) and a steering shaft 2 in accordance with the secondary collision.
When a strong impact load directed to the left) is applied, it can be displaced forward. That is, the supported bracket 3 is fixed to the intermediate portion of the steering column 1 by welding. The supported bracket 3 is formed by bending a steel plate having sufficient rigidity. The intermediate portion is a U-shaped holding portion 4 having an open upper portion.
Are bent at right angles in opposite directions to each other to form a pair of left and right mounting plate portions 5. The steering column 1 is fixed to the holding portion 4 by welding while being held by the holding portion 4 of the supported bracket 3.

A notch is formed in each of the mounting plate portions 5 so as to open to the rear edge side (the right edge side in FIGS. 1 and 6) of each of the mounting plate portions 5. The locking member 6 is fixed inside each of the notches. Each of these locking members 6 is made of a light alloy, a synthetic resin, or the like.
The inside of each of the notches is locked so as to come out of each of the notches when a large impact load is applied.
A through-hole 7 is formed in the center of each of the locking members 6, and the supported bracket 3 is attached to the vehicle body by bolts (not shown) inserted through the through-holes 7 from below to above. It is supported against a fixed part 8a. On the other hand, the front end of the steering column 1 is slidably supported by a front support bracket 9 which is also supported and fixed to a portion 8b fixed to the vehicle body. Therefore, the steering column 1 is supported so that it can be freely displaced (dropped) forward when a strong forward impact load is applied to the vehicle body.

The feature of the present invention resides in the structure of a portion for absorbing the impact energy applied to the steering column 1 at the time of a secondary collision. For the structure of the portion that supports the steering column 1 so that it can be displaced forward in the event of a secondary collision, various structures known in the art, including the structure described above, can be employed. Hereinafter, the structure of the portion that absorbs the impact energy, which is a feature of the present invention, will be described.

In the case of this embodiment in order to absorb the impact energy, a pair of energy absorbing members 10 and 10 are connected to the front edge of the steering column 1 (the left edge in FIGS. 1, 2, 4 and 6). The steering column 1 is provided between the steering column 1 and a handling member 11 which is externally fitted to a portion near the front end of the steering column. Each of the energy absorbing members 10 and 10 is formed in a long U-shape by bending a plastically deformable metal wire (metal wire) such as mild steel. The energy absorbers 13 are bent at right angles from both ends toward the rear (to the right in FIGS. 1, 2, 4, and 6).

The energy absorbing portions 13, 13, near the middle front end thereof, are smoothly bent in a partial arc shape in accordance with the shape of handling passages 14, 14 provided in the handling member 11, which will be described later. The parts 15 and 15 are formed.
Each of the energy absorbing members 10 and 10 locks the base 12 at two positions on the front end edge of the steering column 1, and the energy absorbing members 13 and 1.
3 is disposed rearward along the outer peripheral surface of the steering column 1. For this reason, the length of the base 12 is
The outer diameter of the steering column 1 is made slightly smaller. When absorbing the impact energy applied to the steering column 1 due to the secondary collision, each of the bent portions 1
The front and rear displacements of the steering column 1 are allowed while moving 5, 15 to the rear end side of each of the energy absorbing sections 13, 13 (right side in FIGS. 1, 2, 4, and 6). This point will be described later in detail.

The steering column 1 has a steering column 1 inside a portion near the front end of the steering column 1.
A handle member 11 having a handle passage 14 bent in the axial direction (left and right directions in FIGS. 1, 2, 4, and 6) is fitted around the steering column 1 so as to be freely displaceable in the axial direction. In the illustrated example, the handling member 11 is made of an aluminum alloy or a synthetic resin (having excellent strength and abrasion resistance like a high-performance resin) or the like. It comprises an element 16 and an annular outer element 17 (closed without discontinuities) concentric with each other.

The inner diameter side element 16 has an inner peripheral surface formed into a cylindrical surface, and the inner diameter side element 16 is slidably fitted to the steering column 1 in the axial direction. On the other hand, the outer peripheral surface of the inner diameter side element 16 is curved in a direction in which the central portion in the axial direction is convex and in a direction in which both ends in the axial direction are concave, and these portions are smoothly connected to each other. It has a complex curved surface. At a plurality of positions (four in the illustrated example) of the outer peripheral surface of the inner diameter side element 16, there are handle grooves 21, 21 for forming the respective handle passages 14, 14.
Are formed in the axial direction of the steering column 1, respectively. The bent portions 15, 15 formed on the energy absorbing portions 13, 13 of the energy absorbing members 10, 10, respectively, are substantially unsteady in the respective handling grooves 21, 21 (in a state where only a slight gap is provided). ) Is freely insertable.

On the other hand, the cross-sectional shape of the inner peripheral surface of the outer-diameter element 17 is substantially similar to the cross-sectional shape of the outer peripheral surface of the inner-diameter element 16. That is, the inner peripheral surface of the outer diameter side element 17 is curved in a direction in which the central portion in the axial direction is concave, and in a direction in which both ends in the axial direction are convex, and a composite in which these portions are smoothly connected. It has a curved surface. The outer diameter side element 17 and the inner diameter side element 16 and the energy absorbing members 10 and 10 are combined with each other as follows.

That is, first, the bent portions 15, 15 formed in the energy absorbing portions 13, 13 of the energy absorbing members 10, 10 are respectively provided in the handling grooves 21, 21 formed on the outer peripheral surface of the inner diameter side element 16. Is fitted. In this state, the outer diameter element 16 is fitted to the inner diameter side of the outer diameter element 17 while elastically reducing the outer diameter of the inner diameter element 16. In this way, each of the above members 1
After the combination of 7, 16, and 10, the inner-diameter-side element 16 is externally fitted to a portion near the front end of the steering column 1 from the front end side of the steering column 1 as it is. Then, the bases 12, 12 of the energy absorbing members 10, 10 are brought into contact with the front edge of the steering column 1. In addition, a locking notch is formed as necessary at a portion of the front end edge of the steering column 1 where the bases 12 and 12 abut, so that the steering column 1 can be moved forward when a secondary collision occurs. The bases 12 and 12 do not come off the front edge of the steering column 1.

In this manner, the front end portion of the steering column 1 (see FIG. 4) in which the outer diameter side element 17, the inner diameter side element 16, and the energy absorbing members 10, 10 are mounted near the front end of the intermediate portion. 1, 2, 4, and 6)
It is pushed into the support hole 18 provided in the front support bracket 9 from back to front (from right to left in FIGS. 1, 2, 4, and 6). Notches 19, 19 are formed at a plurality of places (four places in the illustrated example) on the inner peripheral edge of the support hole 18, and elasticity is provided between the notches 19, 19 adjacent in the circumferential direction. The deformed portions 20 are provided. With the front end of the steering column 1 pushed into the support hole 18 of the front support bracket 9, the energy absorbing portions 13 of the energy absorbing members 10, 10 are located in the notches 19, 19. Therefore, there is no interference between the energy absorbing portions 13 and 13 and the front support bracket 9. Also, the inner peripheral edge of each of the elastically deformable portions 20, 20 is:
The steering column 1 extends over almost the entire length of each.
Of the steering column 1
The front end of the is supported without play. In addition, the handling member 11, which includes the inner and outer diameter elements 16 and 17,
It abuts on the rear surface of the front support bracket 9 (the right surface in FIGS. 1, 2, 4, and 6) to prevent forward displacement.

The shock absorbing steering apparatus of the present invention assembled as described above works as follows to protect the driver in the event of a collision. At the time of the secondary collision, a forward-facing load is applied to the steering column 1 from the steering wheel via the steering shaft 2. Then, the steering column 1 is displaced forward together with the supported bracket 3 by this load. At this time, each of the locking members 6 into which a bolt (not shown) has been inserted comes out backward from a notch formed in each of the mounting plate portions 5.

The front end of the steering column 1 is displaced forward while sliding its outer peripheral surface with respect to the inner peripheral edge of each of the elastically deformable portions 20,20. On the other hand, the handling member 11 is restrained by the rear surface of the front support bracket 9, and is not displaced forward while being supported by the vehicle body via the front support bracket 9. For this reason, the handling member 11 is directed toward the rear end of the steering column 1 with respect to the steering column 1 from the state shown in FIG.
As shown in FIG. 6, it is relatively displaced rightward. Therefore, a part of the metal wire constituting the energy absorbing member 10 is handled in the handling passages 14 provided inside the handling member 11. More specifically, of the energy absorbing portions 13, 13, which are a part of the metal wire, each of the handling passages 1
The bent portions 15, 15, which are portions bent according to the shapes of the energy absorbing portions 4, 14, move from the originally formed portions to the rear end sides of the energy absorbing portions 13, 13.

As described above, in order to move the bent portions 15, 15 to the rear end sides of the energy absorbing portions 13, 13, when the energy absorbing portions 13, 13 are plastically deformed, Each bent portion 15, 15 is securely pressed down from the outer diameter side. That is, since the outer-diameter-side element 17 has a cut-out annular shape without a notch, each of the bent portions 15, 15
Is pushed forward, and even if the bent portions 15 press the outer diameter side element 17 outward in the radial direction, the diameter of the outer diameter side element 17 does not increase. Each of the handling passages 14, 14 formed by a part of the inner peripheral surface of the outer diameter side element 17 and the inner surface of each of the handling grooves 21, 21 divides the bending portion 15, 15 into the energy absorbing portion 13. , 13 are securely moved (handled) toward the rear end side.

As described above, the energy absorbing portions 13 and 13 are plastically deformed so as to move the bent portions 15 and 15 to the rear end sides of the energy absorbing portions 13 and 13, respectively. The impact energy applied to the steering wheel from the driver's body due to the collision is absorbed. As a result, the impact on the driver's body is reduced,
The protection of the driver in the event of a secondary collision is achieved.

In particular, in the case of the shock absorbing type steering column apparatus of the present invention, each of the energy absorbing members 10, 1
As 0, a metal wire having a simple shape in which a metal wire is bent into a U-shape and bent portions 15 and 15 are formed in a part thereof is used. And each such energy absorbing member 10,
The structure for absorbing the impact energy can be obtained by a simple assembling operation in which the handle 10 is externally fitted to the front end of the steering column 1 together with the handling member 11. For this reason, welding work for assembling the energy absorbing members 10 and 10 to predetermined portions is not required. In addition, the energy absorbing members 10 and 10 made by bending and forming the metal wire hardly waste material, so that the yield of the material is improved. In addition, since a complicated mold is not required for processing the energy absorbing members 10 and 10, the manufacturing cost can be reduced from this aspect.

Next, FIGS. 7 and 8 show a second embodiment of the present invention. The difference between the structure of the first example described above and the structure of the present example is that a portion that prevents the handling member 11a from being displaced forward during a secondary collision, and a portion that constitutes the handling member 11a during a secondary collision. The two points are to prevent the diameter of the radial element 17a from expanding.

First, the structure of a portion for preventing the handling member 11a from being displaced forward at the time of a secondary collision will be described.
In the case of this example, the front support bracket 9 a for supporting the front end (the left end in FIG. 7) of the steering column 1 with respect to the vehicle body includes a bracket body 22 and a mounting tube 23. The bracket main body 22 has a holding portion 24 formed by bending an intermediate portion of a band-shaped metal plate having sufficient rigidity into a short cylindrical shape, and bending both ends in a radially outward direction to be parallel to each other. A pair of mounting plate portions 25, 25 is provided. The mounting tube 23 is welded and fixed in a state of being bridged between the mounting plate portions 25.

At a plurality of locations (three locations in the illustrated example) in the circumferential direction of the holding portion 24, locking through holes 26, 26 are formed to allow the inner and outer peripheral surfaces of the holding portion 24 to communicate with each other. I have. On the other hand, at a plurality of positions on the outer peripheral surface of the outer diameter side element 17a constituting the handling member 11a, these locking through holes 26, 2
6 are formed with engaging projections 27, 27, respectively. Each of the locking projections 27, 27 is made to enter the inner diameter side of the holding portion 24 by reducing the outer diameter of the outer diameter side element 17a by using the discontinuous portion, and then the outer diameter of the outer diameter element 17a is reduced. By elastically restoring the outer diameter of the side element 17,
It is engaged with each of the locking through holes 26, 26. The energy absorbing members 10, 10 and the inner diameter side element 16 are mounted on the inner diameter side of the outer diameter side element 17a assembled on the inner diameter side of the holding portion 24 in the same manner as in the first example described above. To assemble.

Also in the case of this embodiment, at the time of a secondary collision, the above-mentioned energy absorbing members 10, 10 together with the steering column 1 are provided.
Is displaced forward, so that the energy absorbing portions 1 of each of the energy absorbing members 10 and 10 are moved by the handling member 11a.
The bent portions 15 formed on the energy absorbing portions 3 and 13 are moved toward the rear end side (the right side in FIG. 7) of the energy absorbing portions 13 and 13. At this time, the outer diameter side element 17a is located forward (FIG. 7).
Is applied to the front support bracket 9a based on the engagement between the locking projections 27, 27 and the locking through holes 26, 26. Supported by A radially outward force is applied to the outer diameter side element 17a from each of the bent portions 15, 15, but the outer diameter side element 17a is held down by the holding portion 24 on its outer peripheral surface. Therefore, the diameter of the outer diameter side element 17a does not increase. Therefore, each of the bent portions 15, 15
Is moved to the rear ends of the energy absorbing portions 13 and 13 reliably.

[0028]

The shock absorbing type steering column apparatus of the present invention is constructed and operates as described above, so that a structure capable of reducing the impact at the time of a secondary collision and effectively protecting the driver can be obtained at low cost. Can be In addition, since the installation space for the constituent members does not increase, a compact and lightweight shock absorbing steering column device can be realized.

[Brief description of the drawings]

FIG. 1 is a partial longitudinal sectional side view showing a first example of an embodiment of the present invention in a normal state.

FIG. 2 is an enlarged view of a left end portion of FIG.

FIG. 3 is a view seen from the left side of FIG. 2;

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is a sectional view taken along line BB of FIG. 4;

FIG. 6 is a partial longitudinal side view showing a first example of an embodiment of the present invention in a state at the time of a secondary collision.

FIG. 7 is a view similar to FIG. 2, showing a second example of the embodiment of the present invention;

FIG. 8 is a partial cutaway view from the left side of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steering column 2 Steering shaft 3 Supported bracket 4 Holder 5 Mounting plate 6 Locking member 7 Through hole 8a, 8b Part fixed to vehicle body 9, 9a Front support bracket 10 Energy absorption member 11, 11a Handle member 12 Base DESCRIPTION OF SYMBOLS 13 Energy absorption part 14 Handle passage 15 Bend part 16 Inner diameter side element 17, 17a Outer diameter side element 18 Support hole 19 Notch 20 Elastic deformation part 21 Handling groove 22 Bracket main body 23 Mounting tube 24 Holding part 25 Mounting plate part 26 Shield hole 27 locking projection

Claims (1)

[Claims] The steering column is supported on a vehicle body so that the steering column is free to fall forward when a strong forward shock load is applied to the steering column, and a portion fixed to the vehicle body and the steering column are provided. In the shock absorbing type steering column apparatus provided with an energy absorbing member which serves as a resistance against the forward displacement of the steering column, the energy absorbing member is formed by bending a metal wire. The front end of the steering column is locked to the front end of the steering column, and a handle member having a handle passage bent in the axial direction of the steering column is provided inside the steering column near the front end of the middle portion. The steering column is fitted externally so as to be freely displaceable in the axial direction. In contrast, the metal wires constituting the energy absorbing member are supported in a state where the displacement is prevented from moving forward, and a part of the metal wire constituting the energy absorbing member is inserted from the front toward the rear. Shock absorbing steering column device.