JPS6256015B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an energy absorbing structure in which an energy absorbing member for absorbing impact loads is mounted inside a cover pad disposed at the center of a vehicle steering wheel.

In general, the impact load perpendicular to the front surface of the steering wheel cover pad is larger than the impact load applied diagonally to the front or sideways of the steering wheel cover pad. Therefore, the energy absorbing member installed inside the cover pad is It is preferable that the pad has a large energy absorption characteristic for impact loads in the normal direction, and a small energy absorption characteristic for impact loads in the diagonal or lateral direction of the front surface of the pad.

Conventionally, the energy absorbing member installed in the cover pad of a steering wheel has been formed into a wrapped cylindrical shape, but in this case, a large number of slits were formed in a thin steel plate, which were then bent into a wrapped cylindrical shape. Thereafter, both ends of the bent portion must be joined by welding or riveting to produce an energy absorbing member, which increases costs. Moreover,
If the cover pad is formed into a substantially rectangular box shape for aesthetic reasons, a large space will be created between the outer peripheral surface of the energy absorbing member and the four corners of the cover pad, resulting in a problem that will adversely affect the energy absorption characteristics. .

In view of the above-mentioned reasons, an object of the present invention is to provide a steering wheel cover pad which is formed in a substantially rectangular box shape in consideration of aesthetic design, and which has excellent energy absorption characteristics for impact loads acting on the pad. It is an object of the present invention to provide an energy absorbing structure that allows an energy absorbing member to be easily manufactured and to reduce costs.

A feature of the present invention is that an energy absorbing member having a U-shaped cross section along the inner wall surface of the front plate portion and one opposing side plate portion of the cover pad, which is formed in a substantially rectangular box shape, is provided inside the cover pad. This is where the parts are installed.

An embodiment of the present invention will be described below with reference to the drawings.

Tightening nut 2 on the tip of steering shaft 1
A boss plate 4 is fixed to the boss 3 fixed by the screws 7, and a support plate 6 fixed to the base end of the spoke portion 5a of the steering wheel 5 is fixed to the boss plate 4 by screws 7.

A cover pad 8 is arranged at the center of the steering wheel 5 and covers the front of the boss plate 4.
A cover body 9 made of synthetic resin and having a substantially rectangular box shape;
A pad material 10 made of a flexible synthetic resin such as urethane, rubber, etc. covers the surface of the cover body 9.

An energy absorbing member 11 made of a thin steel plate that is installed inside the cover pad 8 is bent by a press or the like on a front plate 11a along the inner wall surface of the front plate portion of the cover pad 8, and on both upper and lower ends of the front plate 11a. It has upper and lower side plates 11b and 11c along the inner wall surface of the upper and lower side plate parts of 8, and is formed in a U-shape in cross section, and a part of these side plates 11b and 11c are attached to the cover pad 8 by screws 12 and 13. is fixed to the inner wall of the At the tips of both side plates 11b and 11c of the energy absorbing member 11, there is a bent piece 11 supported on the front surface of the boss plate 4 or the front surface of the support plate 6.
d, 11e are formed, and the lower side plate 11c
A mounting piece 15 fixed to the support plate 6 with screws 14 is fixed to the bent piece 11e, while
A clip 16 for clipping onto the boss plate 4 is fixed to the bent piece 11d of the upper side plate 11b.
Further, when an impact load is applied in the direction perpendicular to the front surface of the cover pad 8, the side plates 11b and 11c of the energy absorbing member 11 are arranged so that the side plates 11b and 11c buckle inward at approximately the center thereof.
b and 11c are formed in a dogleg shape in cross section.
Furthermore, when an impact load is applied in a direction parallel to the front plate 11a and both side plates 11b and 11c of the energy absorbing member 11, the side plates 11b and 11c are designed as shown in FIG. In addition, vertically long slit-shaped through holes 17 to 17 are formed at predetermined intervals from the bent portions of the front plate 11a and the side plates 11b and 11c to the central portions of the side plates 11b and 11c in the front and back direction. The energy absorbing member 11 has a large energy absorption characteristic against an impact load in a direction perpendicular to the front surface of the cover pad 8, and a small energy absorption characteristic against an impact load in an oblique or lateral direction to the front surface of the cover pad 8. It is set to have. Furthermore, in consideration of safety, flange portions 11f, 11f are bent with rounded surfaces at both left and right ends of the front plate 11a.

In the above configuration, when an impact load acts in the direction perpendicular to the front surface of the cover pad 8 (direction of arrow A in FIG. 3), this load is transferred to the energy absorbing member 11.
The buckling energy of both side plates 11b and 11c is absorbed by both side plates 11b and 11c. At this time,
The energy absorption characteristics due to buckling of the side plates 11b and 11c are shown by the solid curve in FIG.

Both side plates 11b and 11c of the energy absorbing member 11
When an impact load acts in a direction perpendicular to the energy absorbing member 11 (in the direction of arrow B in FIG. 3), this load becomes a bending moment on both side plates 11b and 11c of the energy absorbing member 11, and is absorbed by the both side plates 11b and 11c.
At this time, the energy absorption characteristic due to the bending of both side plates 11b and 11c is shown by a curved line shown by a chain line in FIG.

When an impact load acts in a direction parallel to the front plate 11a and the side plates 11b, 11c of the energy absorbing member 11 (in the direction of arrow C in FIG. 3), this load is applied to the side plates 11b, 11c of the energy absorbing member 11.
The deflection energy within the plate plane of both sides plates 11
b, 11c. At this time, both side plates 11
The energy absorption characteristics due to the deflection of b and 11c are:
Draw the curve shown by the broken line in Figure 4.

Therefore, considering that the impact load on the front surface of the cover pad 8 of the steering wheel 5 in the perpendicular direction is large, and the impact load on the front surface of the cover pad 8 diagonally or sideways is small.
A favorable energy absorption effect can be obtained against these impact loads.

That is, in the present invention, the cover pad of the steering wheel is formed into a substantially rectangular box shape in consideration of aesthetic design, and the energy absorbing member installed inside the cover pad is attached to the inner wall surface of the front plate portion of the cover pad and one opposite side plate. Since it is formed in a U-shape in cross section along the inner wall surface of the cover pad, this energy absorbing member can effectively absorb the energy of the impact load that acts in the direction perpendicular to the front surface of the cover pad, diagonally in the front surface of the cover pad, or sideways. It can be absorbed and is effective in terms of safety. Moreover, the energy absorbing member can be easily manufactured by bending a thin steel plate into a U-shaped cross section using a press or the like, which is effective in reducing costs.

[Brief explanation of the drawing]

The drawings show one embodiment of the invention.
2 is a front view showing the steering wheel, FIG. 2 is a sectional view taken along the line -- in FIG. 1, FIG. 3 is a perspective view showing the energy absorbing member, and FIG. 4 is an explanatory diagram showing energy absorption characteristics. DESCRIPTION OF SYMBOLS 1...Steering shaft, 3...Boss, 4...Boss plate, 5...Steering wheel, 8...Cover pad, 11...Energy absorption member, 11a...
Front plate, 11b, 11c...Both side plates.

Claims (1)

[Claims] 1. In a steering wheel that is attached to a boss portion at the tip of a steering shaft, a cover pad that is disposed at the center of the steering wheel and covers the front of the boss portion is formed in a substantially rectangular box shape. An energy absorbing structure characterized in that an energy absorbing member having a U-shape in cross section is attached along the inner wall surface of a front plate part and one opposing side plate part.