JPH0236779Y2 - - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention (Field of Industrial Application) The present invention relates to a steering wheel core metal having a ring portion core metal and a spoke portion core metal.

(Prior art) Conventionally, a steering wheel core consisting of a ring core and a spoke core connected to the ring core has been reduced in weight, and at the same time, a coating layer covering the ring core has been developed. In order to prevent rotation and rotation, that is, to prevent rotation, a hollow metal pipe with a non-circular cross section (hereinafter simply referred to as cross section) in the radial direction from the center of the ring core metal, for example, a rectangular hollow metal pipe is used. A proposal has been made to construct the entire ring part core metal.

This ring core metal having a non-circular overall cross section is made by drawing a round pipe to give it a non-circular cross section and then bending it into a ring-shaped object.

(Problems to be Solved by the Invention) However, since the ring portion core metal is manufactured through drawing, bending, etc., the cost becomes relatively high. Another problem is that when a pipe with a non-circular cross section is bent, it tends to twist, making it difficult to butt the ends of the pipe together.

Furthermore, butting both end surfaces of the pipe,
There is a problem in that the workability of butting is poor in any butting of the ring part core metal and the spoke part core metal, and furthermore, butt welding takes time.

These problems become particularly noticeable when a hollow ring core metal 21 with a rectangular cross section is manufactured and a solid spoke core metal 22 is butted against it, as shown in FIG.

In addition, when matching the ends of the spoke part core metal 22 to the outer peripheral surface shape of the ring part core metal 21, it is also possible to finish the end surface of the spoke part core metal 22 to match the abutting surface of the ring part core metal 21. However, not only does this require correspondingly complicated work, but also the design of the steering wheel has to be coordinated with the core metal 22 of the spoke part and the core metal 2 of the ring part.
There is a problem in that a design change to change the joining angle with respect to 1 is inevitable.

Therefore, an object of this invention is to provide a steering wheel core metal that can solve the various problems mentioned above.

Structure of the invention (means for solving problems) This invention provides a steering hole core metal having a ring part core metal and a spoke part core metal joined to the ring part core metal. 1
Consisting of a ring-shaped hollow metal pipe, a part thereof has a circular cross-section, and the other part has a non-circular cross-section that can prevent rotation of the coating layer provided on the outer periphery, and the circular cross-section The above-mentioned problem is solved by forming a steering wheel core metal by butt welding the ends of the spoke core metals.

(Function) Since the attachment portion of the spoke portion core metal to the ring portion core metal has a circular cross section, it is easy to butt the ends of the spoke portion core metal against that portion.

In addition, since the ring part core metal has a non-circular cross section other than the welded part with the spoke part core metal, even if a coating layer is provided on the outer periphery, there will be a gap between the coating layer and the ring part core metal. The rotation is reliably prevented.

(Example) Next, an example embodying this invention will be described based on FIGS. 1 to 5.

As shown in FIG. 1, the steering wheel core metal 3 of this embodiment is arranged with the ring part core metal 1 so that one end faces substantially the center of the ring part core metal 1, and the other end faces the ring part core metal 1. It has two spoke part core metals 2 joined to a ring part core metal 1.

The ring core metal 1 consists of a ring-shaped object P made by processing a hollow metal pipe into a ring shape.The part where the spoke core metal 2 is joined is a circular cross-section part A, and the other parts are circular cross-section parts A. As shown in FIG. 2, the outer cross section is a non-circular cross section B having a substantially square shape.

As shown in FIG. 5, one end of the spoke part core bar 2 is butt-welded to the circular cross-sectional part A.
As shown in FIG. 1, the other end of the spoke part core metal 2 is welded to a boss part 4 provided at the center of the ring part core metal 1.

The spoke portion 2 is made of a solid rod with a rectangular cross section, and the boss portion 4 has an insertion hole 7 into which a steering shaft (not shown) is inserted.
is provided.

The ring core metal 1 of this embodiment is manufactured as follows. In other words, the outer diameter is 15.9mm and the wall thickness is
A ring-shaped object P is manufactured by processing a 1.6 mm steel round pipe into a ring shape, and the part of the ring-shaped object P to which the spoke part core metal 2 is attached is left as it is as the circular cross-section section A, and the other parts are The ring portion core metal 1 is obtained by pressing the portion to form a non-circular cross-sectional portion B.

At this time, the cross section of the ring core metal 1, that is,
The ring portion core metal 1 is pressed so that the cross section when cut in a radial direction around the insertion hole 7 of the boss portion 4 becomes a hollow rectangle as shown in FIG.

Pressing is performed, for example, by the following method.

First, as shown in FIG. 3, a portion of the ring-shaped object P that will become the non-circular cross-sectional portion B of the ring core metal 1 is placed on the lower mold 5 having an inner surface.

Then, an upper mold 6 with an inner surface facing the lower mold 5 is placed on the ring-shaped object P, and the ring-shaped object P is sandwiched between the two molds 5 and 6.

Then, as shown in FIG. 4, when the ring-shaped object P is pressed by applying pressure to the upper mold 6, a ring portion core metal 1 as shown in FIG. 1 is produced.

For this ring part core metal 1, the spoke part core metal 2
By butt welding one end and welding the other end of the spoke part core metal 2 to the boss part 4, the steering wheel core metal 3 is completed.

A steering wheel is completed by covering the steering wheel core metal 3 of this embodiment with a synthetic resin coating layer (not shown) made of polyurethane, soft polyvinyl chloride, or the like.

The steering wheel core metal 3 of this embodiment exhibits the following functions and effects.

Since the ends of the spoke part core metal 1 abut against the circular outer circumferential surface of the ring part core metal 2, no matter what the joining angle of the ring part core metal 2, the spoke part core metal 1 will remain as shown in FIG. The gap between the end of the metal 2 and the outer circumferential surface of the ring core metal 1 is constant, and this gap serves as a notch for appropriate welding, so the ring core metal 1 and the spoke core metal 2 are The effect is that stable bonding is possible.

Therefore, in the steering wheel core metal 3 of this embodiment, the butt welding strength is improved, and the design of the steering wheel is improved so that the joining angle of the spoke part core metal 2 is as shown by the two-dot chain line in FIG. Even when changing the spoke part core metal 2, the ring part core metal 1 and the spoke part core metal 2 can be easily joined without changing the design of the end portion of the spoke part core metal 2.

This effect is achieved when the wall thickness of the ring core metal 1 is 1.4 mm or more.
It is particularly noticeable when it is preferably 1.6 to 2.0.

Furthermore, the spoke part core metal 1 has a non-circular cross section B.
Therefore, even if the ring core metal 1 is coated with a coating layer made of polyurethane, soft polyvinyl chloride, etc., the rotation/rotation of the coating layer due to twisting between the coating layer and the ring core metal 1 is prevented, i.e. , the rotation is reliably stopped. Moreover, since only a part of the ring-shaped object P is pressed, not all of it, the manufacturing cost of the steering wheel core metal is lower than that of the conventional one.

This invention is not limited to the above embodiments, but
For example, the following embodiment can also be used.

(1) The shape of the non-circular cross section B may be any non-circular shape that prevents the coating layer from rotating, and may be, for example, a gourd shape. However, considering various factors such as the ability to prevent the coating layer from rotating against the ring core metal due to twisting, the strength of the ring core metal 1, and the ease of press working, the most preferable non-circular shape is a square or nearly square. be.

(2) The spoke core metal 2 may be a plate-like material as long as it is made of a solid metal material, and its cross-sectional shape can be arbitrarily selected as required. The number of spoke portion core metals and the attachment locations can also be arbitrarily selected.

Effects of the invention Since the welding area between the ring core metal and the spoke core metal has a circular cross section, no matter what the joining angle of the spoke core metal, the outer peripheral surface of the ring core metal and the spoke core metal The gap at the end of the spoke part becomes constant, and it is easy to butt the end of the spoke part core metal against the ring part core metal. Therefore, butt welding between the ring portion core metal and the end portions of the spoke portion core metal is stabilized, and welding strength is improved.

In addition, even when changing the joint angle of the spoke core metal, the spoke core metal can be easily attached to the ring core metal without changing the design of the ends of the ring core metal and the spoke core metal. Can be done.

In addition, since the ring part core metal has a non-circular cross section other than the welded part with the spoke part core metal, even if a coating layer is provided on the outer periphery, there will be a gap between the coating layer and the ring part core metal. Rotation can be reliably prevented.

[Brief explanation of the drawing]

Figure 1 is a front view of the steering wheel core metal.
Figure 2 is a sectional view taken along the - arrow in Figure 1;
The figure is a cross-sectional view showing a ring-shaped object sandwiched between molds for non-circular processing. Figure 4 is a cross-sectional view showing a ring-shaped object processed into a non-circular shape.
FIG. 6 is a partial sectional view showing a state in which a spoke part core metal is joined to a ring part core metal in a steering wheel core metal manufactured by a conventional method. Ring part core metal 1, spoke part core metal 2, steering wheel core metal 3, circular cross-section part A, non-circular cross-section part B.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. In a steering wheel core 3 having a ring core 1 and a spoke core 2 joined to the ring core 1, one ring core 1 is provided. It is composed of a ring-shaped hollow metal pipe, a part of which has a circular cross section A, and the other part a non-circular cross section B that can prevent the coating layer provided on the outer periphery from rotating, and the circular cross section A steering wheel core metal characterized in that an end of the spoke part core metal 2 is butt-welded to part A. 2. The steering wheel core metal according to claim 1, wherein the circular cross-sectional portion A has a wall thickness of 1.4 mm or more. 3. The steering wheel core metal according to claim 1, wherein the spoke portion core metal 2 is made of a solid metal.