JPS6027724Y2 - Shock absorbing steering device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an impact-absorbing steering device that absorbs impact energy at the time of a collision of an automobile at a joint between a boss portion of a steering wheel and a steering shaft.

In such conventional shock-absorbing steering devices, the boss portion of the steering wheel and the steering shaft are connected by a plastically deformable connecting member, and compressive plastic deformation occurs at the bent, folded, or folded portion of the connecting member. However, the amount of impact energy absorbed was not necessarily large.

SUMMARY OF THE INVENTION An object of the present invention is to increase the amount of impact energy absorbed in an impact-absorbing steering device that absorbs impact energy at the time of a car collision at a joint between a boss portion of a steering wheel and a steering shaft.

In order to achieve this object distantly, the shock absorbing steering device of the present invention is provided with a tapered member provided on at least one of the opposing ends of the boss portion of the steering wheel and the steering shaft; A coupling member that can be plastically deformed by fitting into the tapered surface of the steering wheel couples the boss portion of the steering wheel and the steering shaft.

During a collision, the tapered member advances toward the coupling member in the axial direction, and as a result, the coupling member is plastically deformed to expand radially outward due to the tapered surface of the tapered member, and this plastic deformation releases impact energy. is absorbed.

The amount of plastic deformation caused by the radial expansion of the coupling member by the tapered member is larger than that of compressive plastic deformation such as simple bending of the coupling member, so the amount of energy absorption can be significantly increased.

Next, embodiments of the present invention will be described with reference to the drawings.

The steering wheel 1 includes a ring portion 2, spoke portions 3, and a boss portion 4.

A cushion member 5 is stretched over the upper surfaces of the spoke portions 3 and the boss portions 4.

A shock absorbing member 6 serving as a coupling member that couples the boss portion 4 and a steering shaft (to be described later) has a bottom surface 7, and a plurality of strip portions 8 formed in a strip shape extend upward from the periphery of the bottom surface 7 ( Figure 2).

The strip portion 8 is arranged in an annular shape and is folded back radially outward at the upper end.

The lower peripheral edge part 13 of the boss part 4, which also serves as a tapered member, is formed in a downwardly concave shape, the lower surface center part 14 is formed in a downwardly concave tapered shape, and the strip part 8 of the shock absorbing member 6 is formed in a tapered shape. It is press-fitted into the lower center portion 14.

A reinforcing plate 9 is fixedly provided on the bottom surface 7 of the shock absorbing member 6, and a steering shaft 11 extending inside the column tube 10 is fixed to the bottom surface 7 with a bolt 12 at its upper end.

Rotation of the steering wheel 1 is transmitted to the steering shaft 11 via the shock absorbing member 6.

At the time of a collision (Fig. 3), the boss portion 4 moves downward in the axial direction,
With this movement, the upper end of the strip portion 8 of the shock absorbing member 6 expands radially outward along the tapered lower surface central portion 14, comes into contact with the concave lower surface peripheral portion 13, and is thus plastically deformed.

Since the upper end of the strip portion 8 is guided by the concave lower surface peripheral portion 13 and folded back downward, the upper end of the strip portion 8 is prevented from flying upward and causing injury to the driver.

The initial folding of the upper end of the strip portion 8 serves to smooth the folding in the event of a collision.

FIG. 4 shows the deformation of the boss portion 4.

A groove 16 corresponding to the strip portion 8 of the shock absorbing member 6 is formed in the center portion 14 of the lower surface of the boss portion 4 .

The strip portion 8 of the shock absorbing member 6 is press-fitted into the groove 16.

This embodiment is advantageous in that it improves prevention of circumferential slippage between the boss portion 4 and the shock absorbing member 6.

In FIG. 5, the upper end of the strip portion 8 of the shock absorbing member 6 is screwed to the tapered central portion 14 of the boss portion 4 by the head of a bolt 20. As shown in FIG.

In Fig. 6, the strip portion 8 is formed by resin injection 22.
is fixed to the tapered central portion 14 of the boss portion 4.

At the time of collision, the resin injection 22 is damaged by a predetermined shearing force, allowing relative movement between the boss portion 4 and the strip portion 8.

FIG. 7 shows another embodiment of the invention.

The boss portion 17 of the steering wheel 1 is formed in a planar shape, and the shock absorbing member 6 is fixed to the boss portion 17 with its bottom surface 7 upside down compared to the embodiment shown in FIG.

A new boss member 18 is provided which is fixed to the steering shaft 11 with a bolt 12. The side surface of the boss member 18 is tapered upward and has a suitable step 19, so that the side surface of the boss member 18 is formed to have an appropriate step 19. The strip portion 8 is press-fitted into the boss member 18.

In this embodiment, the tip of the strip portion 8 is not folded back.

In the event of a collision, the tip of the strip portion 8 comes into contact with the step 19 and is expanded radially outward by the tapered side surface of the boss member 18, thereby absorbing the impact energy by plastic deformation of the strip portion.

In this embodiment, the tip of the strip portion 8 moves downward in the event of a collision and does not fly out toward the driver, so there is no need to take precautions to prevent it from jumping out toward the driver as in the embodiment shown in FIG. It is.

Figures 8 and 9 show other embodiment variations of the invention.

One boss member 30 constitutes a boss portion of the steering wheel 1, and the other boss member 31 is fixed to the steering shaft 11 with bolts 25.

The boss member 30 has a structure similar to that of the boss portion 4 described above, that is, it has a downwardly tapered central portion 32 and a downwardly concave peripheral portion 33.

The boss member 31 has a similar structure to the above-described boss member 18, that is, it has a tapered side surface 34 that tapers upward.

A linear member 35 serving as a coupling member for coupling the boss portion 5 and the steering shaft 11 is folded back radially outward and downward at the upper end, and is press-fitted and fixed into the boss members 30 and 31 on both sides.

The entire linear member 35 has a constricted portion formed at the center in the axial direction.

As shown in FIG. 13, in the event of a collision, the linear member 35 is plastically deformed at its upper end by the boss member 30 and at its lower end by the boss member 31, and the impact energy is absorbed by this plastic deformation.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a perspective view of the boss portion and shock absorbing member shown in FIG. 1, and FIG. 3 is a diagram showing the state of the embodiment shown in FIG. 1 at the time of a collision. 4 is a diagram showing a modification of the boss portion in FIG. 1, FIGS. 5 and 6 are diagrams each showing another manner of coupling the boss portion and the shock absorbing member, and FIG. 7 is a modification of the boss portion in FIG. 1. 8 and 9 are diagrams showing other embodiments of the present invention. 1... Steering wheel, 4...
Boss portion, 6...Shock absorbing member, 11...
・Steering shaft, 18.30.31...
・Boss member, 35... Linear member.

Claims (1)

[Scope of utility model registration request] A tapered member is provided on at least one of the opposing ends of the boss portion of the steering wheel and the steering shaft, and a coupling member that can be plastically deformed by fitting into the tapered surface of the tapered member is provided at the end portion of the boss portion of the steering wheel. A shock absorbing steering device characterized by combining a steering shaft and a steering shaft.