JPH0382680A - Outer material forming method for steering wheel - Google Patents

Abstract

PURPOSE:To simplify the forming process of seams and reduce the cost by sticking the outer skin to a covering material made of soft synthetic resin and covering the core metal of a steering wheel, forming seams at the edge section of the outer skin, and winding and sticking the covering material to the core metal. CONSTITUTION:For forming the outer material of a steering wheel, a covering material 8 made of a soft synthetic resin material such as urethane and covering a core metal 5 is injection-molded with a mold. The outer skin 9 made of leather or a synthetic resin sheet and cut to the size of the covering material 8 is stuck on the surface of the covering material 8 with an adhesive to manufacture an outer material 6A. Both edge sections of the outer skin 9 are folded inward and stuck to both end faces of the covering material 8. Seams 7 are formed on the edge section of the outer material 6A with a thread 11 by using a sewing machine, for example. The outer material 6A formed with seams 7 is wound on the core metal 5 of a wheel section 2 at the preset position, and the back face of the covering material 8 is stuck to the core metal 5 with an adhesive.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for forming an exterior material on a core bar of a steering wheel, and particularly relates to a method for forming an exterior material having anti-slip and decorative seams. It is.

[Prior Art] FIG. 6 is a perspective view showing the entirety of a steering wheel used in an automobile or the like. As is well known, the steering wheel 1 includes a wheel portion 2, spoke portions 3, a boss portion (not shown), and a butt portion 4 that covers the boss portion. The wheel portion 2 is formed by fixing an exterior material 6 to the outside of a core metal 5, and an anti-slip and decorative seam 7 is formed on the inner peripheral surface of the exterior material 6. In addition, the outer skin of the exterior material 6, such as leather, usually includes a portion that covers the wheel portion 2;
It is divided into a portion that covers the connecting portion between the wheel portion 2 and the spoke portion 3, and is formed into an annular integral body by connecting each divided piece by stitching or the like.

When attaching the sheathing material 6 having this type of seam 7 to the core bar 5, the method shown in FIGS. 7 to 9 has conventionally been adopted.

FIG. 7 is a perspective view showing a first conventional method of forming a steering wheel exterior material. Here, the core bar 5 is first insert-molded with a covering material 8 made of a soft synthetic resin such as urethane foam, then the covering material 8 is covered with an outer skin 9 made of leather or a synthetic resin sheet, and then, Outer skin 9
The joints were sutured with thread 11 using needle 10.

FIG. 8 is a perspective view showing a second conventional method for forming a steering wheel exterior material. Here, the core bar 5 is insert-molded with a covering material 8 in the same manner as in the first conventional example, and then the covering material 8 is covered with an outer skin 9 having pseudo seams 12 formed on both side edges. The outer skin 9 was adhered to the surface of the covering material 8, and the surfaces of the outer skin 9 to be joined together were adhered to each other.

FIG. 9 is a sectional view showing a third conventional method for forming a steering wheel exterior material disclosed in Japanese Patent Application Laid-Open No. 49-76234. Here, the core bar 5 is first insert-molded with an outer core member 13 made of a hard synthetic resin, then a covering material 8 made of a soft synthetic resin or rubber is applied to the outer surface of the outer core member 13, and then , the covering material 8 is covered with an outer skin 9, and then, after folding both side edges of the outer skin 9 into the groove 14 of the outer core member 13, a wedge 15 having a pseudo seam 12 on the outer surface is inserted into the groove 14. The outer skin 9 was press-fitted to prevent the outer skin 9 from peeling off.

[Problems to be Solved by the Invention] However, according to the method of the first conventional example, when sewing the outer skin 9, it is necessary to keep pulling the outer skin 9 strongly, which not only involves great labor but also makes it difficult to sew beautiful stitches. In order to form the eyes 7, it is necessary for a skilled person to spend a considerable amount of time, resulting in a problem of increased costs. Further, according to the method of the second conventional example, since the adhesion area of the surfaces of the outer skin 9 that are joined together is small, there is a risk that the joined portions will peel off over time. Furthermore, according to the third conventional example, in particular,
Since the process of molding the outer core member 13 and the process of press-fitting the wedge 15 are required, there is a problem that the total number of man-hours increases and process control becomes complicated.

Therefore, an object of the present invention is to simplify the seam forming process, and
An object of the present invention is to provide a method for forming an exterior material for a steering wheel, which can reduce manufacturing costs, firmly fix the exterior material to a core metal, and reliably prevent peeling of the exterior skin.

[Means for Solving the Problems] In order to solve the above problems, the method for forming an exterior material for a steering wheel of the present invention includes a step of molding a covering material that covers a core metal using a soft synthetic resin material. , a step of adhering an outer skin to the surface and both end faces of the covering material to obtain an outer covering material, a step of forming a seam at the edge of the outer covering material before attaching the outer covering material to the core metal, The process consists of the steps of attaching the back side of the sheathing material to the core metal, and bonding the outer skins of the parts adhered to both end faces of the sheathing material to each other, thereby attaching the seamed sheathing material to the core metal.

[Function] According to the method for forming a steering wheel exterior material of the present invention, the seams are formed in a substantially flat state before the exterior material is attached to the core metal, so even non-experts can easily form the seams. Beautiful seams can be formed. In addition, when the sheathing material is attached to the core metal, the back side of the sheathing material is adhered to the core metal, and the outer skin of the parts adhered to both end faces of the sheathing material is adhered to each other over a wide area, so that the wedge The sheathing material can be easily and firmly fixed to the core bar without using separate members such as, and peeling of the sheath can be reliably prevented.

[Example] Hereinafter, an example embodying the present invention will be described based on the drawings.

1 to 4 show an embodiment of the method for forming a steering wheel exterior material according to the present invention, and FIG. 2 is a perspective view showing a state in which the exterior material 6B is attached to the core bar 5 at the connection portion between the wheel portion 2 and the spoke portion 3, and FIG. 3 is a perspective view illustrating the manufacturing process of the exterior material 6A shown in FIG. , FIG. 4 is a perspective view illustrating the process of forming the exterior material 6B of FIG. 2.

Now, in the steering wheel 1 of this embodiment, the exterior material 6 has two parts: one part is attached to the core metal 5 of the wheel part 2, and the other part is attached to the core metal 5 at the connection part between the wheel part 2 and the spoke parts 3. It is divided into two parts. In the final form in which these exterior materials 6 are attached to the outer periphery of the core metal 5, the sixth
It shows the same form as the conventional steering wheel 1 shown in the figure.

In FIG. 1, 6A indicates an exterior material attached to the core bar 5, and this exterior material 6A includes a covering material 8 made of soft synthetic resin such as foamed urethane bonded to the core bar 5, and the covering material 8. It consists of an outer cover 9 made of leather or synthetic resin sheet adhered to the surface and both end faces of the cover. The edges of the outer skin 9 are bonded to both end surfaces of the covering material 8 on the inner peripheral side of the outer covering material 6A, and are bonded to each other at both joint surfaces. Furthermore, a seam 7 formed by a thread 11 is formed at the joint portion on the inner peripheral side of the exterior material 6A so as to be exposed on the surface of the wheel portion 2 (see FIG. 6). Note that the seams 7 function as anti-slip and decorative purposes, and do not have the function of fixing the exterior material 6A to the core bar 5.

On the other hand, as shown in FIG. 2, the exterior material 6B attached to the core metal 5 at the connection portion between the wheel portion 2 and the spoke portions 3 is formed into a substantially T-shape. This exterior material 6B is also the exterior material 6A.
Similarly, it is composed of a covering material 8 and an outer skin 9, and the edges of the outer skin 9 are bonded to each other while being sandwiched between both end surfaces of the covering material 8, and the joints and both ends of the outer covering material 6B are bonded to each other. , a seam 7 is formed with a thread 11.

In the above configuration, next, a method of forming the exterior material of the steering wheel will be described.

First, as shown in FIG. 3(a), the covering material 8 covering the core metal 5 is injection molded to a predetermined size using a mold using a soft synthetic resin material such as urethane. Similarly, as shown in FIG. 4(a), a coating material 8 covering the core metal 5 at the connection portion between the wheel portion 2 and the spoke portions 3 is injected in a cross shape using a mold. Shape.

Next, as shown in FIG. 3(b), an outer skin 9 made of leather or synthetic resin sheet cut to match the size of the covering material 8 is attached to the covering material 8 using an adhesive (as shown in the diagram). An exterior material 6A for the core bar 5 of the wheel portion 2 consisting of a coating material 8 and an outer skin 9 is manufactured by adhering it to the surface. In this case, both edges of the outer skin 9 are folded inward and adhered to both end surfaces of the covering material 8. Similarly, as shown in FIG. 4(b), an outer skin 9 is adhered to the surface and all end faces of the cross-shaped covering material 8, thereby connecting the covering material 8 and the outer skin 9. Fabricate the exterior material 6B for the section.

Next, before attaching the exterior materials 6A and 6B to the core bar 5,
As shown in FIG. 3(C), a seam 7 is formed on the edge of the exterior material 6A with thread 11 using, for example, a sewing machine, and as shown in FIG. 4(C), the exterior material 6A is A seam 7 is formed at the edge of the material 6B.

Thereafter, as shown in FIG. 1, the sheathing material 6A with the seams 7 formed thereon is wrapped around the core bar 5 of the wheel section 2 at a predetermined position, and the back surface of the sheathing material 8 is glued with adhesive (as shown in the diagram). Adhere to the core bar 5. Further, as shown in FIG. 2, the exterior material 6B is folded over the core bar 5 at the connecting portion between the wheel part 2 and the spoke part 3, and the back surface of the sheathing material 8 is glued (as shown) to the core bar. 5
Glue to.

In this state, next, the portion of the exterior material 6A where the outer skin 9 is joined together, and the portion of the exterior material 6B where the outer skin 9 is joined together are bonded to each other with an adhesive (the path shown in the figure).

Then, after correcting the postures of the exterior material 6A and the exterior material 6B, the connection surfaces of both are bonded to each other with an adhesive (as shown in the diagram).

After that, if you wait for the adhesive on each part to harden, the exterior material 6
A is fixed to the core bar 5 of the wheel part 2, and the exterior material 6B is fixed to the core bar 5 at the connection part between the wheel part 2 and the spoke part 3, thereby forming a steering wheel as shown in FIG. 1 is completed.

As described above, the method for forming the exterior material of a steering wheel according to this embodiment includes the steps of injection molding the covering layer 8 covering the core bar 5 from a soft synthetic resin material using a mold, and forming the surface of the covering material 8. and the step of gluing the outer skin 9 to both end faces to obtain the outer covering materials 6A and 6B, and before attaching the outer covering materials 6A and 6B to the core bar 5, stitches 7 are formed with threads 11 on the edges of the outer covering materials 6A and 6B. and bonding the back side of the sheathing material 8 to the core metal 5, and bonding the outer skins 9 of the parts adhered to both end faces of the sheathing material 8 to each other to form the sheathing material A having the seam 7 and B
The process consists of the step of attaching the metal core 5 to the core metal 5.

Therefore, according to the method for forming a steering wheel exterior material according to the second embodiment, the exterior materials 6A and 6B have seams 7 in a substantially planar state before being attached to the core metal 5. is formed, so even non-experts can easily form beautiful seams 7. Furthermore, when the sheathing materials 6A and 6B are attached to the core bar 5, the back surface of the sheathing material 8 is adhered to the core bar 5, and the surfaces of the outer sheaths 9 that are joined to each other are bonded to each other over a wide area. Unlike the conventional method, the sheathing members 6A and 6B can be easily and firmly fixed to the core metal 5 without using a separate member such as a wedge, and peeling of the sheath 9 can be reliably prevented.

Incidentally, in the above embodiment, the surfaces of the outer skin 9 that are joined to each other are formed flat, and the flat surfaces of both hands are bonded to each other with an adhesive, but the joining structure of this part is as shown in FIG. It is also possible to configure

FIG. 5 is a sectional view showing another embodiment of the method for forming a steering wheel exterior material according to the present invention.

Here, a protrusion 17 is provided protrudingly on one end surface of the covering material 8, and a recess 18 into which the protrusion 17 fits is formed on the other end surface of the covering material 8. In addition, on both edges of the outer skin 9,
One hole into which the projection 17 is inserted is formed. Therefore, according to this configuration, not only the portion of the outer skin 9 that joins with each other, but also the protrusion 17 and the recess 18 are bonded to each other with an adhesive (not shown), so that the area is wider than that of the above embodiment. The bonding area allows the bonded portions of the exterior materials 6A and 6B to be firmly bonded, and it is possible to reliably prevent peeling of the exterior skin 9 due to twisting during operation, for example.

Further, in the above embodiment, the seam 7 is formed across the edges of the sheathing materials 6A and 6B, that is, the sheathing material 8 and the outer skin 9. However, the present invention is not limited to this, and the seam 7 is A seam 7 is formed only on the outer skin 9 having the seam 7.
It is also possible to adopt a method in which the exterior materials 6A and 6B are manufactured by bonding the exterior materials 6A and 6B to the covering material 8.

Further, in the above embodiment, the seam 7 is formed by the thread 11, but the present invention is not limited to this, and if the outer skin 9 on which a pseudo seam (see FIG. 8) is formed is used. However, it provides anti-slip and decorative functions. Note that the direction of the seam and the pseudo-seam is not limited to the illustrated example of FIGS. 1 and 2, and may be parallel to the joining line of the exterior materials 6A and 6B.

Furthermore, in the second embodiment, the injection molding process of the covering material 8 and the adhesion process of the outer skin 9 are separate, but after the seam 7 is formed at the edge of the outer skin 9, this seam 7 is Applied outer skin 9
is set in an injection mold, and injection molding of the covering material 8 and joining of the outer skin 9 are simultaneously performed by in-mold molding.
Thereafter, the outer skin 9 may be folded back and bonded to both end surfaces of the covering material 8 to obtain the outer covering material 6. In this way, manufacturing time can be shortened and an adhesive for bonding the outer skin 9 to the covering material 8 can be made unnecessary.

[Effects of the Invention] As detailed above, the method for forming a steering wheel exterior material of the present invention includes the steps of molding a covering material covering a core bar using a soft synthetic resin material, and A process of gluing the outer skin to the surface and both end faces of the sheath to obtain the sheathing material, a process of forming seams at the edges of the sheath before attaching the sheathing material to the core metal, and a process of attaching the back side of the sheathing material to the core metal. The method consists of the steps of attaching the sheathing material with seams to the core metal by adhering the outer skins of the parts adhered to both end faces of the sheathing material to each other, and attaching the sheathing material with seams to the core metal. This has the effect of simplifying the process and reducing manufacturing costs, as well as firmly adhering the sheathing material to the core metal and reliably preventing peeling of the sheath.

[Brief explanation of drawings]

1 to 4 show an embodiment of the method for forming the exterior material of a steering wheel according to the present invention, FIG. 1 is a perspective view showing the state where the exterior material is attached to the core bar of the wheel portion, and FIG. FIG. 3 is a perspective view illustrating the manufacturing process of the exterior material shown in FIG. 1, and FIG. 4 is FIG. 2. It is a perspective view explaining the manufacturing process of the exterior material of. FIG. 5 is a sectional view showing another embodiment of the method for forming a steering wheel exterior material according to the present invention. FIG. 6 is a perspective view showing the appearance of the steering wheel. FIGS. 7 to 9 are explanatory diagrams illustrating different conventional methods of forming exterior materials for a steering wheel. In the figure, 1 Steering wheel 5: Core metal 6A, 6B
: Exterior material 7: Seam 8: Covering material
9: Outer skin. In the drawings, the same reference numerals and the same symbols indicate the same or equivalent parts.

Claims (1)

[Claims] (1) A step of molding a sheathing material covering a core metal using a soft synthetic resin material; A step of adhering an outer skin to the surface and both end faces of the sheathing material to obtain an exterior material; Before attaching to the core metal, there is a step of forming a seam on the edge of the outer skin, adhering the back side of the covering material to the core metal, and bonding the parts of the outer skin glued to both end faces of the covering material to each other. A method for forming an exterior material for a steering wheel, comprising the steps of: attaching an exterior material having seams to a core bar.