JPS60112429A - Manufacture of steering wheel - Google Patents

Abstract

PURPOSE:To manufacture various kinds of steering wheel in small quantity at low cost by a method wherein a core material covered with expandable soft vinyl chloride resin is expansion-molded by high-frequency heating in a simple mold made of material having a small power factor such as silicone resin or the like. CONSTITUTION:A corel made of material with small power factor such as polypropylene or the like or of material with high thermal deformation temperature such as polycarbonate or the like is shaped into the form of steering wheel. A covered body 3 consisting in covering said core 1 with pieces 2 of expandable soft vinyl chloride resin having large power factor is arranged in simple forces 5 and 5', both of which are made of material with small power factor such as silicone resin or the like and pinched between electrodes 6 in order to expand the pieces 2 by applying high frequency voltage. Because the mold made of resin with small power factor is employed, only vinyl chloride resin can be efficiently expanded. In addition, because the mold itself is cheap, the provision of various kinds of mold is made possible, resulting in enabling to mold various kinds of steering wheel in small quantity at low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is often used for automobiles, forklifts, abrasive trucks, or those made of urethane resin, and the former is generally manufactured by injection molding, and the latter by reaction injection molding.

-1-1c7 By the way, the steering wheel is often replaced depending on the driver's preference, which necessitates the production of a wide variety of products in small quantities.

However, all of the above-mentioned manufacturing methods require large equipment such as injection molding machines and molds, and are not suitable for high-mix, low-volume production.

In addition, both manufacturing methods involve press-fitting molten resin etc. into a mold, holding it,
Since it is a cooling product, it is difficult to obtain a lightweight product or a product with a soft feel, especially if it is made of highly foamed material.

Therefore, in view of these points, the present invention aims to provide a novel method for manufacturing a handle that can easily produce a wide variety of products in small quantities. A piece of non-foamed or low-foamed soft vinyl chloride resin containing the agent is coated on a core material with a relatively low power factor or high heat deformation temperature, and the underarm cover is installed indoors, and then the cover is passed through the back of the shoe. A high frequency voltage is applied to the soft seeded vinyl piece, the soft seeded vinyl piece is melted by the self-heating effect of the high frequency, and the blowing agent contained in the soft vinyl chloride resin is decomposed by the extreme heat, and the decomposed gas causes the soft chloride to melt. The present invention provides a method for manufacturing a handle in which a vinyl piece is made into a highly foamed material and shaped into a hollow cavity shape, and the armpit foam and core material are integrated.

The present invention will be explained below based on examples. FIG. 1 is a plan view of the handle core, and FIGS. 2(a) and 2(b) are sectional views of a piece of soft vinyl chloride resin for coating.

The handle core body 1 is made of a plastic molded product having a low power factor, such as polyphenylene oxide or polypropylene, or a plastic having a high heat distortion temperature, such as polycarbonate, polyamide, polyimide, etc.

The soft vinyl chloride resin piece 2 contains an azo compound represented by azosica-bonamide, N, and dimethyl N.

Most of the non-foamed or foaming agent is composed of unfoamed, low-foamed material into which a desired amount of a decomposed layer foaming agent such as a nitroso compound represented by N'-dinitroterephthalamide is kneaded. The type and amount of the foaming agent are selected to be suitable for obtaining the desired foaming ratio. For example, to obtain a product with double foaming ratio,
~3 parts by weight of blowing agent. The soft seeded vinyl resin piece 2 is previously shaped into a flat plate shape as shown in FIG. 2 (a) or a cylindrical shape as shown in FIG.

Soft vinyl chloride resin is a typical plastic with a high power factor among plastics, and the present invention utilizes it.

Next, the manufacturing method of the present invention will be explained. First, the core body 1 is coated with a soft vinyl chloride resin piece 2. When the soft vinyl chloride resin piece 2 is flat, it can be wrapped around the core 1; when it is cylindrical, one piece is cut out and covered.

Next, as shown in FIG. 3, this covering 6 is supported at several points around the circumference of the handle by means of a support part (not shown) on the undershoe 5 having a cavity 4 having a predetermined handle shape.

3- W5, 5' is made of a material with a low power factor such as yycon resin or epoxy resin, and is designed to reduce self-heating in the rearward process.

Next, the upper mold 5' is closed, the mold 5 and the electrode 51 are sandwiched between the electrodes 6 as shown in FIG. 4, and a high frequency is applied to the covering body 6 through the mold 5.5I. Then, since the housing 5.5' is made of a material with a low power factor, high frequency waves act on the covering body B installed on the mold 5.51. Soft vinyl resin piece 2
As mentioned above, since the power factor is large, it rapidly self-heats and melts. As a result, the foaming agent kneaded into the soft cyclized vinyl resin piece is also thermally decomposed, and the released gas causes the soft cyclized vinyl resin piece 2 to foam, and its volumetric expansion fills the inside of the cavity 4 to form a predetermined cavity shape. The outer layer 2' is formed into a shape.

On the other hand, when the core 1 in the cover 6 is made of a material with a small power factor, it maintains its original shape without generating much heat, just like the mold 5.5', and is made of foamed soft vinyl chloride. It will be located approximately at the center of the outer resin layer 2I. In addition, when the core body 1 is made of a material with a high heat deformation temperature such as polycarbonate, it will be held in the foamed soft vinyl chloride with almost no deformation even if the power factor is small or large. .

FIG. 5 shows the state.

Furthermore, if a colored film or a film with a pattern printed thereon is placed in the wound cavity prior to installing the covering body 6, a handle having an arbitrary color or pattern can be obtained.

Further, although the solid core 1 is shown in the above embodiment, a round and hollow core may be used in combination with semicircular cores. In that case, the weight can be further reduced.

As described above, the present invention covers a handle core body with a small power factor or a handle core body with a high heat deformation temperature with a piece of soft cyclized vinyl resin containing a foaming agent and having a high power factor of non-foaming or low foaming. , the coating is made of WK with a low power factor such as plJcon resin.
The device selectively heats and melts the soft vinyl chloride resin piece using high frequency waves, and decomposes the foaming agent in the soft vinyl chloride resin piece using cough heat to produce nine handles covered with a foamed soft vinyl chloride layer. Because of this, the foaming ratio can be adjusted as desired, and a handle that is highly foamed, that is, lightweight, can be manufactured.

The mold only needs to be kept closed at a pressure that exceeds the foaming pressure by the decomposition gunu, and the mold can be simply cast using v-recon resin, etc., so conventional equipment that is very dusty can be used. This has the advantage that the molds are not required, and the molds can be changed and created at any time, making it possible to produce a wide variety of products in small quantities.

Furthermore, it also has the advantage that handles of various designs can be manufactured by combining pieces of different colored soft vinyl chloride resin coated on the handle core, or by combining colored film stops as needed. It is industrially useful as a manufacturing method that can adapt to diversifying needs.

[Brief explanation of the drawing]

i@Figure 1 is a plan view of a core body according to an embodiment of the present invention, Figure 2 is a cross-sectional view of a soft vinyl chloride resin piece, and Figure 6 is an apparatus in which the core body is coated with a soft vinyl chloride resin piece and the nine-covered body is molded into a mold. FIG. 1 is a cross-sectional view taken along the line A--A, FIG. 4 is a cross-sectional view showing the high frequency application method, and FIG. 5 is a cross-sectional view of the gripping portion of the product.

Claims (1)

[Claims] A piece of non-foamed or low-foamed soft vinyl chloride resin that has a high power factor and contains a foaming agent is coated on a core material that has a relatively low power factor or a high heat distortion temperature, and the coated body is installed indoors. Then, by applying a high frequency voltage to the covering body through the trailing dust, the soft seeded vinyl resin layer is heated and melted, and the foaming agent is decomposed, so that a soft vinyl chloride resin foam layer of a desired shape is formed around the core material. A method for manufacturing a handle characterized by: