WO2011158621A1

WO2011158621A1 - Steering column mounting bracket

Info

Publication number: WO2011158621A1
Application number: PCT/JP2011/061981
Authority: WO
Inventors: 正志安藤; 修司吉川; 善一川田; 康弘谷岡
Original assignee: ヒルタ工業株式会社; 株式会社ジェイテクト
Priority date: 2010-06-16
Filing date: 2011-05-25
Publication date: 2011-12-22
Also published as: CN102933449A; JP2012001080A

Abstract

Provided is a steering column mounting bracket such that load-deflection characteristics can be easily adjusted, and that in particular, peak loads can be easily raised. The steering column mounting bracket is a support member which has a bent cross section, and causes a steering column to be supported by a vehicle body member. The support member comprises a mounting surface which is fixed to the vehicle body member; a support surface which is mounted on the steering column; a main bent edge which is a connecting portion between the mounting surface and the support surface, and which extends in a direction that intersects the steering column at right angles; and a bead which is disposed in such a way as to intersect the main bent edge while extending over the mounting surface and the support surface and. Thus the features mentioned above are achieved.

Description

Steering column mounting bracket

The present invention relates to a mounting bracket for supporting a steering column on a vehicle body side member.

The vehicle steering mechanism (steering mechanism) is composed of a steering shaft with a handle attached thereto and a steering column in which the steering shaft is rotatably stored. The steering column is supported by the vehicle body side member via a support member. It is sufficient for the steering mechanism to be able to stably support the steering column on the vehicle body side member. Recently, in addition to this, a steering mechanism is desired to prevent a “secondary collision” in which a driver hits a steering wheel and is damaged when a vehicle collides. In order to achieve this object, a steering mechanism incorporating an impact absorbing device that absorbs the impact energy of a secondary collision has been proposed.

As a shock absorber for the steering mechanism, a ripping plate type that absorbs impact energy by tearing a dedicated plate (ripping plate) or bending deformation (plastic deformation) of the support member that attaches the steering column to the body side member is used. There is a bending type that absorbs impact energy. The latter shock absorbing device is preferable because it does not require additional members to be added to the steering mechanism and thus has a simple structure. For example, as in Patent Document 1, a configuration using bending deformation (plastic deformation) of a mounting bracket that supports a steering column with respect to a vehicle body side member has been proposed.

Patent Document 1 discloses an L-shaped cross section that connects an attachment surface (first plate portion 35) fixed to a vehicle body side member, a support surface (second plate portion 36) attached to a steering column, and the attachment surface and the support surface. A connecting surface having a shape (connecting plate portion 37), a main bent edge (first bent portion 38) formed between the mounting surface and the connecting surface and extending in the left-right direction of the vehicle body, and between the support surface and the connecting surface. A lower secondary bent edge (second bent portion 39) that is formed and extends in the left-right direction of the vehicle body, and an upper secondary bent edge (separated from the main bent edge and the secondary bent edge and provided on the connecting plate portion ( A third mounting bracket 40) is disclosed (claim 1 of patent document 1 and others). The mounting bracket of Patent Document 1 is excellent in that the bending of the upper and lower sub-bending edges is caused to bend and the support surface (second plate portion 36) is translated to prevent the steering column from being twisted. It is supposed that the absorption of the impact energy is realized (Patent Document 1, FIG. 5 and others).

The mounting bracket of Patent Document 1 adjusts load displacement characteristics (particularly peak load) by changing the overall shape and thickness, or by opening through holes (45, 46) over each surface or across each surface. . However, it is difficult to adjust the load displacement characteristics by changing the overall shape or the plate thickness, and there is a problem that it cannot be adjusted as designed. In addition, the adjustment of the load displacement characteristics by the through holes can be adjusted only in the direction of decreasing the peak load by facilitating bending deformation, and cannot be adjusted in the direction of increasing the peak load (Patent Document 1 [0006], etc.) ).

JP 2008-087537 A

The object of the present invention is to provide a steering column mounting bracket in which the load displacement characteristics can be easily adjusted, and in particular, the peak load can be easily increased.

A support member having a bent cross section for supporting a steering column on a vehicle body side member, the support member including an attachment surface fixed to the vehicle body side member, a support surface attached to the steering column, the attachment surface and the support A main bending edge extending in the orthogonal direction of the steering column, and a bead arranged across the mounting surface and the support surface so as to intersect the main bending edge. The above problem is solved by the mounting bracket of the steering column. As long as the bead can intersect the main bending edge, the outer shape, the cross-sectional shape, and the depth of the bead are not particularly limited. If the bead has an directional outer shape, the bead is preferably orthogonal to the main bent edge.

The mounting bracket of the present invention constitutes an impact absorbing device for the steering mechanism. When the steering column receives an impact, the steering column moves forward. Since the end of the steering column is attached to the support surface of the mounting bracket, the support surface advances together with the steering column. On the other hand, since the mounting surface of the mounting bracket is fixed to the vehicle body side member, when the support surface moves forward, the support surface is bent and deformed across the main bending edge to absorb impact energy. In the mounting bracket of the present invention, a bead is formed across the mounting surface and the support surface so as to intersect the main bending edge, thereby increasing the rigidity at the main bending edge. Further, the load displacement characteristic is improved by increasing the bending stress required for the bending deformation generated across the main bending edge (the peak load is increased and the energy absorption amount is also increased).

The outer shape or cross-sectional shape and depth of the bead (hereinafter referred to as an outer shape or the like) is not particularly limited, and the load displacement characteristic by the mounting bracket is adjusted by adjusting the outer shape or the like. The specific outer shape or the like of the bead also depends on the outer shape of the mounting bracket, the degree of interference with other members associated with the steering mechanism, and the vehicle body side member. However, the positions of the bead start end (bead start at the mounting surface) and bead end (bead end at the support surface) are all within the range of the mounting surface and support surface, and the bead cross section is the periphery of the mounting surface or support surface. It is desirable to configure so that it does not appear in More specifically, the bead intersects a line (fastening line) connecting a mounting portion (screw hole or the like) to the vehicle body side member on the mounting surface, and the bead starting end is positioned between the peripheral edge of the mounting surface and the fastening line. Good.

The support surface includes an upper support surface connected to the main bent edge of the mounting surface, a lower support surface attached to the steering column, and is sandwiched between the upper support surface and the lower support surface in a direction orthogonal to the steering column. The bead may be configured to be disposed across the attachment surface and the upper support surface so as to intersect the main bending edge. There may be a plurality of minor folding edges. In this case, if the folding direction is changed for each minor folding edge (for example, the bending direction is changed in the order of mountain folding, valley folding, and mountain folding), the lower support surface is impacted. Therefore, it is possible to move the steering column integrally with the forward moving steering column, so that the forward moving steering column is not twisted. The effect of increasing the peak load and increasing the amount of energy absorption is not impaired.

The mounting bracket of the present invention has the effect of improving the rigidity at the main bent edge by forming a bead that intersects the main bent edge, and in particular has the effect of increasing the peak load. Deformation is difficult to occur, and the function of the mounting bracket as an impact absorbing device is impaired. Therefore, in order to moderately reduce the peak load that has become too high by forming the bead, the bead may be provided with a through hole to reduce the rigidity at the main bent edge. The outer shape and size of the through holes are determined so that the rigidity due to the formation of the beads is lowered and the peak load is within the allowable range of the required design value.

Also, as described above, in order to reduce the peak load that has become too high by forming the bead, the bead may be formed with a dent (driving) at a position that coincides with the main bent edge. The dent is a part that facilitates bending deformation of the bead, and has a function of reducing rigidity due to the formation of the bead. As long as the bending deformation of the bead can be promoted in this way, the dent may be formed on either the front surface side or the back surface side of the bead. The cross-sectional shape and depth of the dent are determined so that the rigidity due to the formation of the bead is lowered and the peak load is within the allowable range of the required design value.

According to the present invention, it is possible to easily adjust the load displacement characteristics of the mounting bracket constituting the shock absorbing device of the steering mechanism. This is an effect by the bead arrange | positioned so that a main bending edge may be crossed first. And this invention also brings about the effect which enlarges the adjustment width | variety of the load displacement characteristic of the said mounting bracket. This is an effect due to the bead increasing the peak load and increasing the adjustment range of the energy absorption amount. According to the required specifications, it is possible to easily adjust the load displacement characteristics by providing a bead with a through hole or a dent to reduce the peak load. According to the present invention, since it is easy to realize the required load displacement characteristics (particularly peak load), the quality can be maintained even if, for example, the number of samples for sampling inspection is reduced.

¡By forming a bead so as to intersect the main bent edge, the rigidity of the mounting bracket is increased at the main bent edge. Even if the thickness of the mounting bracket to which the present invention is applied is reduced, a necessary and sufficient load displacement characteristic can be secured. Therefore, the material cost can be reduced by using a plate material thinner than the conventional mounting bracket. Further, the weight can be reduced. In particular, the weight-reduced mounting bracket has a higher natural vibration value than the conventional mounting bracket of the same type, and brings about a secondary effect of suppressing the vibration of the supporting steering column. Thus, the present invention not only improves the load displacement characteristics of the mounting bracket as an impact absorbing device, but also improves the cost and mechanical properties required for manufacturing the mounting bracket as a structural member.

It is the perspective view which looked at an example of the attachment bracket to which this invention was applied from the front direction. It is a front view of the mounting bracket of this example. It is a side view of the steering column supported by the vehicle body side member by the mounting bracket of this example. It is the perspective view equivalent to FIG. 1 which looked at the attachment bracket (without a through-hole) of another example from the front direction. It is the perspective view equivalent to FIG. 1 which looked at the mounting bracket (bead is equal width) of another example from the front direction. It is the perspective view equivalent to FIG. 1 which looked at the attachment bracket (bead start end appears in the periphery of an attachment surface) of another example from the front direction. It is the perspective view equivalent to FIG. 1 which looked at the mounting bracket (single support surface) of another example from the front direction. It is a side view of the mounting bracket of this example which supported the steering column. FIG. 4 is a side view corresponding to FIG. 3 of the mounting bracket of this example that is plastically deformed by absorbing impact energy.

Hereinafter, modes for carrying out the present invention will be described. The present invention is, as shown in FIGS. 1 to 3, for example, a mounting bracket 1 constituting an impact absorbing device for a steering mechanism. In the mounting bracket 1 of this example, a mounting surface 11 fixed to the vehicle body side member 3 and an upper support surface 12 mounted to the steering column 2 have a main bent edge 14 extending perpendicularly to the steering column 2. The bead 15 is disposed across the attachment surface 11 and the upper support surface 12 so as to form a bent cross section through the main bending edge 14. The attachment surface 11 is provided with a pair of left and right bolt notches (attachment portions) 111 and 111 on the periphery parallel to the main bent edge 14. The bead starting end 151 intersects the fastening line connecting the

bolt notches

111 and 111 and extends toward the peripheral edge, and is positioned between the peripheral edge of the mounting surface 11 and the fastening line.

The mounting bracket 1 is bent and deformed with respect to the mounting surface 11 via the main bent edge 14. The support surface in this example is divided into an upper support surface 12 and a lower support surface 13. Specifically, an upper support surface 12 descending obliquely rearward (leftward in FIG. 1) from the mounting surface 11 and a lower support surface 13 orthogonal to the steering column 2 are connected by an intermediate surface 122. The bead end 152 is within the range of the upper support surface 12. A shaft through hole 132 through which a steering shaft (illustrated) extending from the steering column 2 passes is arranged at the center of the lower support surface 13. The mounting bracket 1 and the steering column 2 are joined by a connecting bolt 21. The mounting bracket 1 is provided with a pair of bolt holes 133 through which the connecting bolts 21 are inserted at diagonal positions with the shaft through hole 132 interposed therebetween.

The mounting surface 11 and the upper support surface 12 are valley-folded (concave section with respect to the right side in FIG. 3) via a main bending edge 14 orthogonal to the steering column 2. The bending angle between the mounting surface 11 and the upper support surface 12 in this example is 135 degrees. The upper support surface 12 and the intermediate surface 122 are mountain-folded (a convex cross section with respect to the right side in FIG. 3) via a first sub-bending edge 121 orthogonal to the steering column 2. The bending angle between the upper support surface 12 and the intermediate surface 122 in this example is 105 degrees. The lower support surface 13 and the intermediate surface 122 are folded at a valley (a concave cross section with respect to the right side in FIG. 3) via a second auxiliary folding edge 131 orthogonal to the steering column 2. The bending angle between the lower support surface 13 and the intermediate surface 122 in this example is 90 degrees.

The steering column 2 is connected to the lower support surface 13 of the mounting bracket 1 as shown in FIG. A bolt hole 133 through which the connecting bolt 21 is inserted is provided in the lower support surface. The steering column 2 is supported by a vehicle body side member (for example, a deck cross member) 3 through a mounting bracket 1. A steering shaft (not shown) extending from the steering column 2 extends forward (rightward in FIG. 3) through the shaft through hole 132 of the lower support surface 13. The steering column 2 is supported by another part of the vehicle body side member 3 via the auxiliary bracket 22. The auxiliary bracket 22 is configured so that the steering column 2 can be easily separated when an impact is applied from the rear of the steering column 2 by, for example, a driver hitting a handle (not shown) in the event of a collision. .

The feature of the mounting bracket 1 of the present invention is a bead 15 formed so as to intersect the main bent edge 14. The bead 15 of the present example is a convex part that bulges forward a square plane in front view. As described above, the bead starting end 151 extends from the upper side of the square convex portion toward the periphery of the mounting surface 11 so as to intersect the fastening line connecting the

bolt notches

111 and 111. As a result, the rigidity reduction of the mounting surface 11 due to the provision of the bolt notch 111 is reinforced by the bead starting end 151. In the bead 15 of this example, a through-hole 153 is provided in a plane extending over the upper support surface 12, and a recess (driving) 154 is formed at a position corresponding to the main bent edge 14. In this example, the through hole 153 and the recess 154 reduce the rigidity of the main bent edge 14 that is excessively increased, and easily cause bending deformation to absorb impact energy.

FIG. 4 shows another embodiment of the mounting bracket of the present invention. Similar to the bead 15 of this example, the bead 16 of another example is provided with a bead start end 161 and a bead end end 162, and a recess 164 is formed at a position corresponding to the main bent edge 14. However, the bead 16 is not provided with a through hole. Due to this difference, in another example, the rigidity at the main bent edge 14 is higher than in this example.

FIG. 5 shows another embodiment of the mounting bracket of the present invention. The bead end 172 of another example bead 17 is the same as this example. However, the bead 17 of another example eliminates a through hole and a dent, makes the mounting surface 11 wider than the present example, makes the bead start end 171 wider, and increases the rigidity at the main bent edge 14, so that this example Is different. The beat start end 171 intersects with the fastening line connecting the

bolt notches

111 and 111 and extends toward the periphery of the mounting surface 11, and the width of the bead start end 171 is the same as that of the main body of the bead 17. Further, as shown in FIG. 6, the main bent edge 14 is formed as a bead 18 in which the width of the mounting surface 11 and the bead end 182 are the same as the bead 17 and the bead starting end 181 reaches the periphery of the mounting surface 11. The rigidity of the bead 17 may be slightly lower than that of the main bent edge 14 of the bead 17.

The present invention can be applied to various conventionally known mounting brackets 1 that exhibit an impact absorbing function by plastic deformation in addition to the above-described examples (FIGS. 1 to 6). For example, as shown in FIG. 7, it comprises a single support surface 193 provided with a hinge flange 195 for supporting (tilting) the steering column 2 so that it can be swung up and down, and a mounting surface 11. In the case of the mounting bracket 1, a bead 19 is provided across the main bent edge 14 that is a boundary between the mounting surface 11 and the support surface 193 by applying the present invention. The bead 19 of this other example has the same width from the bead start end 191 to the bead end 192 and forms a recess 194 at a position corresponding to the main bent edge 14.

Thus, the outer shape, cross-sectional shape, and depth of the bead 15 are not particularly limited. The presence or absence of through holes or dents is not particularly limited. However, from the viewpoint of improving the rigidity at the main bent edge 14, it is preferable to satisfy the following relationship when L1, L2, L1, L2, F1, and F2 are defined as shown in FIG. . By satisfying this relationship, it is possible to prevent the bend end from being bent before the main bent edge 14. As long as this relationship is satisfied, the outer shape, cross-sectional shape, and depth of the bead 15 are not particularly limited, and the presence or absence of a through hole or a dent is not particularly limited.
L1 × F / Z1> L2 × F / Z2
Z1: Section modulus L1 of the mounting bracket 1 including the bead 15 at the main folding edge 14: Main folding from the load point M that is the intersection of the axis of the steering column 2 to which the lower support surface 13 is attached and the lower support surface 13 Distance Z2 to bead 15 at curved edge 14: Section modulus L2 of mounting bracket 1 of bead end 152 at upper support surface 12: Intersection of axis of steering column 2 to which lower support surface 13 is attached and lower support surface 13 The distance F from the load point M to the bead end 152 is a load applied to the load point M.

When the mounting bracket 1 in which the bead 15 is formed according to the above relationship receives a load F from the steering column 2 due to an impact, the upper support surface 12 reduces the bending angle with respect to the mounting surface 11 as shown in FIG. In addition, the impact is caused by bending deformation so that the intermediate surface 122 increases the bending angle with respect to the upper support surface 12 and the lower support surface 13 increases with respect to the intermediate surface 122. Absorb energy. Since the first sub-folding edge 121 and the second sub-folding edge 131 are bent and deformed, the lower support surface 13 moves in parallel with the steering column 2. Therefore, the lower support surface is not inclined and deformed with respect to the steering column that moves forward, and the steering column is not twisted.

The mounting bracket 1 absorbs impact energy mainly by bending deformation at the main bent edge 14. In the case of this example, bending deformation at the first sub-folding edge 121 and the second sub-folding edge 131 also contributes to the absorption of impact energy. The bead 15 prevents the bending deformation at the main bending edge 14 and increases the bending stress necessary to cause the bending deformation, thereby increasing the peak load and increasing the energy absorption amount. The mounting bracket 1 of this example causes the main folding edge 14 to bend and deform so that the upper support surface 12 with respect to the mounting surface 11 has a small bending angle. This is a plastic deformation that generates excess meat in the bead 15, and usually excessively increases the bending stress required to cause the bending deformation. The dent 154 absorbs the excess meat of the bead 15 by its own shape deformation (in this example, it is deep with respect to the plane of the bead 15), and facilitates bending deformation of the bead 15 itself.

1 Mounting Bracket 11 Mounting Surface 12 Upper Support Surface 13 Lower Support Surface 14 Main Bending Edge 15 Bead 2 Steering Column 21 Connecting Bolt 22 Auxiliary Bracket 3 Car Body Side Member 31 Fixing Bolt

Claims

A support member having a bent cross section for supporting the steering column on the vehicle body side member;
The support member is an attachment surface fixed to a member on the vehicle body side, a support surface attached to a steering column, and a joint portion between the attachment surface and the support surface, and extends in a direction orthogonal to the steering column. A steering column mounting bracket, comprising: a bent edge; and a bead arranged across the mounting surface and the support surface so as to intersect the main bent edge.
The support surface includes an upper support surface connected to a main bent edge of the mounting surface, a lower support surface attached to the steering column, and an orthogonal position of the steering column sandwiched between the upper support surface and the lower support surface. It consists of a minor folding edge that extends in the direction,
2. The steering column mounting bracket according to claim 1, wherein the bead is arranged across the mounting surface and the upper support surface so as to intersect a main bending edge. 3.
The steering column bracket according to claim 1, wherein the bead is provided with a through hole.
The steering column mounting bracket according to any one of claims 1 to 3, wherein the bead has a recess at a position corresponding to the main bent edge.