JPH0584565U - Steering wheel core metal - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a steering wheel mandrel that has a light weight structure, good productivity, and has energy absorption characteristics within a certain range regardless of the direction of impact load. To do. [Structure] A boss portion 1 in which an upper spoke constituent portion 1a, 1a 'and a lower spoke constituent portion 1b, 1b' are integrally cast-molded,
Upper spoke attachment parts 2a, 2a 'and lower spoke attachment parts 2b,
2b 'and a rim portion 2 integrally formed by casting, and an upper spoke
Between the spoke constituent portions 1a, 1a 'and the upper spoke attachment portions 2a, 2a' and between the lower spoke constituent portions 1b, 1b 'and the lower spoke attachment portions
A plurality of loop-shaped absorbing members 3 inserted between 2b and 2b '
A steering wheel core metal is composed of A, 3A ', 3B and 3B'.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a steering wheel core metal that absorbs an impact load when a driver or a passenger in a passenger seat collides with a steering wheel used in an automobile or the like.

[0002]

[Prior Art]

 When the front part of a vehicle such as an automobile collides with an obstacle, the driver is suddenly moved forward by inertial force. Also, when an obstacle collides with the side of the vehicle, the passenger occupant is suddenly moved to the side. Depending on the extent of the collision, the chest or the like of the driver or the passenger in the passenger seat may be strongly hit on the steering wheel and seriously injured. In order to prevent serious injury, it is desirable that the steering wheel absorb as much as possible the impact energy generated when the driver's or passenger's chest or the like is strongly hit against the steering wheel.

As a device that absorbs impact energy, a shock absorbing structure for a steering wheel has been conventionally proposed, as disclosed in, for example, Japanese Patent Laid-Open No. 3-99975. This is because the rim and the column mounting portion arranged in the center of the rim are connected and fixed by several spokes, and a coil is provided at a portion between the rim of the spoke and the column mounting portion. It is characterized in that a section is provided. With this configuration, when an impact load is applied to the steering wheel, this impact load is absorbed by the expansion and contraction action of the coil section, and the expansion and contraction action of the coil section affects the impact load that acts on the steering wheel. Since it becomes almost constant irrespective of the direction of action, there is an effect that the energy absorption characteristic can be made constant regardless of the direction in which the impact load is applied.

[0004]

[Problems to be solved by the device]

 However, in the above-mentioned conventional technology, as can be seen by referring to the embodiments, only the coil portion for absorbing impact energy is formed only in the middle portion on the left and right of the upper spoke, and the shape of the figure eight is formed. No coil is provided on the lower spoke that has been bent in the direction of 0.Therefore, even if the energy absorption characteristic is constant regardless of the direction in which the impact load is applied, it depends on which part of the rim the load acts on. Energy-absorption characteristics vary. In particular, the energy-absorption characteristics are inferior to the impact load applied from the lateral direction (passenger side).

Further, the above publication does not describe the material of the rim, the column mounting member, the upper spoke and the lower spoke, but according to the ordinary knowledge of those skilled in the art, a steel rim is not used. On the other hand, it is considered that the upper and lower spokes made of steel were welded, and both spokes were welded to the steel column mounting member. However, if steel is used as in the conventional example, there is a limit to achieving sufficient weight reduction even if the rim or the like is made into a hollow pipe. In order to exceed this limit, there has been provided a Mg alloy which is capable of casting a steering wheel core metal, which is lightweight and has excellent strength and rigidity, as an integral body for the purpose of improving productivity (Japanese Patent Laid-Open Publication No. Sho. 61-243147 and JP-A-61-243148). That is, when manufacturing a steering wheel core metal, in order to improve the productivity, it is effective to cast and mold the core metal not as an assembly but as an integral body, which is particularly suitable for mass production. Adoption of die casting method is recommended.

However, in the die-casting method, it is difficult to form a coil portion in the portion related to the shock absorbing structure, that is, the intermediate portion on the left and right of the upper spoke in the above-mentioned conventional technique. Obtaining the desired impact energy-absorption characteristics is even more difficult.

The present invention has been made in view of the above-mentioned problems of the prior art, and has a light weight structure, high productivity, and a certain energy absorption characteristic regardless of the direction in which an impact load is applied. The object is to provide a steering wheel core metal that fits within the range.

[0008]

[Means for Solving the Problems]

 A boss portion in which the upper spoke constituent portion and the lower spoke constituent portion are integrally cast-molded, and a rim portion in which the upper spoke attachment portion and the lower spoke attachment portion are integrally cast-molded, A plurality of loop-shaped absorbent members inserted between the upper spoke constituent portion and the spoke attachment portion and between the lower spoke constituent portion and the lower spoke attachment portion, The steering wheel core metal consisting of Further, it is preferable to provide the boss portion 1 with a radial shock absorbing shape. Further, it is preferable that the boss portion and the rim portion are cast and formed by a die casting method of Mg alloy, and the loop-shaped absorbing member to be inserted is made of steel.

[0009]

【Example】

 An embodiment of the present invention will be described with reference to the drawings. 1 is a plan view of a steering wheel core metal according to the present invention, FIG. 2 is a sectional view taken along the line AA of FIG. 1, FIG. 3 is a sectional view taken along the line BB of FIG. 1, and FIG. FIG. 3D is a sectional view taken along line CC of FIG. It consists of three major components, 1 is a boss, 2 is a rim, and 3 is a loop-shaped absorbent member.

The boss portion 1 is made of Mg alloy, and the upper spoke constituent portions 1a and 1a ', the lower spoke constituent portions 1b and 1b', and the shock absorbing shape 1c are integrally cast and formed by a die casting method. It is a thing. As shown in FIG. 1, the upper spoke constituent portions 1a and 1a 'are protrusions protruding in the directions of approximately 3 o'clock and 9 o'clock. The lower spoke components 1b, 1b 'are protrusions protruding in the directions of 4:30 and 7:30. As shown in FIG. 3, the upper spoke constituent portion and the lower spoke constituent portion form a constant inclination angle α with respect to the horizontal plane. As shown in FIG. 3, the front ends of the upper spoke constituent portion and the lower spoke constituent portion are provided with insertion holes into which loop-shaped absorbing members 3 described later can be inserted. The shock absorbing shape 1c extends radially in eight directions around the center of the boss 1 (Fig. 1), and each of them has a step shape (Fig. 2).

The rim portion 2 is also made of Mg alloy, and the upper spoke attachment portions 2a and 2a 'and the lower spoke attachment portions 2b and 2b' are integrally cast by a die casting method. The cross section of the rim body is U-shaped in order to reduce the weight, and the tips of the upper spoke attachment portion and the lower spoke attachment portion can be inserted with the loop-shaped absorbing member 3 as shown in FIG. An insertion hole is provided. Since the upper spoke attachment portion 2a is a protrusion provided at a position facing the upper spoke constituent portion 1a of the boss portion 1, the upper spoke attachment portion 2a is located in the direction of about 3 o'clock. The same applies to the upper spoke attachment portion 2a 'and the lower spoke attachment portions 2b and 2b'.

The loop-shaped absorbing members 3A, 3A ', 3B, 3B' are made of steel, and one of the loop-shaped absorbing members 3B will be described. One end of the loop-shaped absorbing member 3B is described. It is inserted into the insertion hole of the lower spoke constituent portion 1b of the above, and the other end is inserted into the insertion hole of the lower spoke attachment portion 2b of the rim portion 2 (Fig. 3). Then, the two inserted places are welded.

[0013]

[Effect of the device]

 Since a plurality of loop-shaped absorbing members are provided between the boss and the rim, and a radial shock absorbing shape is provided on the boss, the chest or the like of the driver or passenger in the event of a collision of the automobile, etc. Even if the vehicle is strongly hit by the steering wheel, the collision energy can be sufficiently absorbed, so that the driver or the like can be prevented from being seriously injured. Further, due to the synergistic effect of the radial impact absorbing shape and the plurality of loop-shaped absorbing members, a constant energy absorbing characteristic can be obtained regardless of the point of action in the action direction of the impact load. As a result, there are problems such as unevenness and non-uniformity of gas in the airbag due to the difference in energy absorption characteristics (or strength difference) between the 12 o'clock side and the 6 o'clock side of the rim, which is a problem when deploying the airbag. It can be resolved. Further, it is possible to manufacture a lightweight steering wheel core metal having excellent impact energy absorption characteristics, which could not be realized by combining the Mg alloy and the steel material, while maintaining high productivity.

[Brief description of drawings]

FIG. 1 is a plan view of a steering wheel core metal according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

4 (C) is a sectional view taken along line CC of FIG. 3, and FIG. 4 (D) is taken along line D- of FIG.
D sectional view.

[Explanation of symbols]

1 Boss 1a, 1a 'Upper spoke component 1b, 1b' Lower spoke component 1c Impact absorbing shape 2 Rim 2a, 2a 'Upper spoke attachment 3b, 3b' Lower spoke attachment 3A, 3A ', 3B, 3B' Loop-shaped absorbing member

Claims (3)

[Scope of utility model registration request] 1. A boss portion in which an upper spoke constituent portion and a lower spoke constituent portion are integrally cast-molded, and an upper spoke attachment portion and a lower spoke attachment portion are integrally cast-molded. A plurality of loops inserted between the rim portion, the upper spoke constituent portion and the upper spoke attachment portion, and between the lower spoke constituent portion and the lower spoke attachment portion. Steering wheel core metal consisting of a strip-shaped absorbing member. 2. The steering wheel core metal according to claim 1, wherein the boss portion is provided with a radial shock absorbing shape. 3. The steering wheel according to claim 1 or 2, wherein the boss portion and the rim portion are cast and formed by a Mg alloy die casting method, and the loop-shaped absorbing member to be inserted is made of steel. Le core metal.