JPH03281475A - Manufacture of steering wheel core - Google Patents

Abstract

PURPOSE:To form a locking part at a low cost by pressure-deforming the outer surface of a ring section with die-cast molding dies so as to form the locking ring as a cover layer during the fastening of the die-cast molding dies. CONSTITUTION:When a ring section 2 is set in a die-cast molding die, two to three slidable dies are provided on a stationary die 6a, for retaining the ring section 2 so as to direct the same toward the center of the die 6a. After the ring section 2 is temporarily held, the dies are fastened while the slidable dies are moved outward by cams formed to a movable die 6b, and finally, the ring section 2 is directly pressed by the movable die 6b. Since a plurality of pressing projections 7 are formed on the stationary and movable dies 6a, 6b along the parting line, the inner and outer peripheral surfaces of the ring section 2 are locally press-deformed by the projections 7, thereby it is possible to project locking parts 4.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method of manufacturing a core metal for a steering wheel that includes a locking portion for a coating layer.

[Conventional technology]

The ring part of a steering wheel is generally made of a metal core covered with a resin coating layer such as urethane, and this coating layer is often bonded to the ring part made of iron vibrator etc. by applying an adhesive. . However, with this structure, there is a risk that the adhesive part may peel off due to aging and the coating layer may rotate relative to the pipe, so it is necessary to use a material with an irregular cross section for the ring part or to form a locking part with unevenness. Mechanical locking of the coating layer has also been carried out (for example, Utility Model Application Publication No. 59-17)
2066, Utility Model Application Publication No. 60-135266, etc.).

[Problem to be solved by the invention]

The problem with conventional locking parts as described above is that they not only complicate the manufacturing process, but also often require additional parts, leading to many factors that increase costs. There was a point. The present invention has focused on such problems and has been made for the purpose of forming a locking part at low cost.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention provides a method for manufacturing a core metal for a steering wheel in which a spoke part is integrally formed in a ring part by a die-casting method. By deforming the outer surface of the ring part under pressure, a locking part for the covering layer is formed.

[Effect]

According to this invention, the die-casting mold is also used to form the locking part, so by forming the die-casting mold into a predetermined shape, the locking part is automatically formed, and the locking part is formed. No special process or materials are required.

【Example】

Next, one embodiment shown in the drawings will be described. Figure 1 is a front view of the embodiment, Figure 2 is a perspective view of its main parts, and Figures 3 to 5.
The figure is an explanatory diagram of the pressurizing process, and FIG. 6 is a perspective view of the main parts of another embodiment. In the figure, l is the core metal of the steering wheel, 2 is the ring part, 3 is the spoke part, 4 is the locking part formed in plurality on the ring part 2, 5 is the boss part, and 6 is movable with the fixed mold 6a. This is a die-casting mold consisting of a mold 6b. The core metal 1 of the steering wheel is made by setting the ring part 2 and the boss part 5 made of, for example, iron pipes in a predetermined position in a die-casting mold 6 as shown in FIG. 3(a), and then forming the core metal 1 as shown in FIG. After the mold is clamped, die casting is performed by supplying materials such as A, (1, Mg) into the cavity 6c having a shape corresponding to the spoke part 3, and forming the ring part 2 and the boss part 5 into the spoke part 3.
Manufactured by integrating through. Figure 3 (
d) shows the extrusion process using the extrusion bottle 6d. FIG. 4 shows an example of a mold structure for correctly setting the ring part 2 in the die-casting mold 6, in which a slide mold 6e that presses the outer periphery of the ring part 2 toward the center is placed in a fixed mold 6a.
~3 are provided, and after temporarily holding and positioning the ring part 2, slide cams 6r formed on the movable mold 6b
The slide mold 6e is moved outward and clamped, and finally the ring portion 2 is directly pressurized with the movable mold 6b. A plurality of pressure protrusions 7 are formed on the fixed mold 6a and the movable mold 6b along the parting line as shown in FIG. 5(a). The outer periphery and inner periphery of the ring portion 2 are partially deformed by pressure, so that a locking portion 4 as shown in FIG. 2 is made to protrude. The pressurizing protrusion 7 is designed to correspond to the shape of the locking part 4 to be formed, and for example, as shown in FIG. 5(b), a mold 6a and a mold 6
It can also be provided only on one side of b. In this way, according to this embodiment, no special process or material is required to form the locking portions 4, and the plurality of locking portions 4 are automatically formed when the die-casting mold 6 is clamped. The covering layer to be adhered around the ring portion 2 in a later step is mechanically locked by the locking portion 4. In addition to forming a plurality of independent locking portions 4 as described above, the locking portions 4 may be formed continuously over the entire length of the ring portion 2 as illustrated in FIGS. 6(a) and 6(b). Often, the shape and number can be selected as appropriate.

【Effect of the invention】

As is clear from the above-mentioned embodiments, the present invention is configured to deform the outer surface of the ring part under pressure with the die-casting mold when the die-casting mold is clamped, thereby forming a connecting part for the coating layer. It is something. Therefore, the manufacturing process requires only the same die-casting process as conventional methods, no special process for forming the locking part, and no separate parts are required, reducing manufacturing costs. It becomes possible.

[Brief explanation of drawings]

FIG. 1 is a front view of a core metal according to an embodiment of the present invention, and FIG.
The figure is a perspective view of the main parts, Figures 3 (a) to (d) are explanatory diagrams of the die-casting process, and Figures 4 (a) and (b) are the metal parts used to set the ring part in a predetermined position. An explanatory diagram of the mold structure, FIGS. 5(a) and (b) are explanatory diagrams of the main parts of the mold and the locking part forming process, and FIGS. 6(a) and (b) are main parts of other embodiments. FIG. 1...Core metal, 2...Ring part, 3...Spoke part,
4... Locking part, 5... Boss part, 6... Die casting mold, 6a... Fixed mold, 6b... Movable mold, 6c...
・Cavity, 6d...Extrusion bottle. 6e...Slide type, 6"...Slide cam, 7...
Pressure protrusion.

Claims (1)

[Claims] 1. In a method for manufacturing a core metal (1) for a steering wheel in which spoke parts (3) are integrally formed on a ring part (2) by a die-casting method, when the die-cast mold (6) is clamped, the die-cast metal A method for manufacturing a core metal for a steering wheel, characterized in that a locking part (4) for a coating layer is formed by pressurizing and deforming the outer surface of a ring part (2) with a mold (6).