JPS608018A - Preparation of headrest - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention relates to a method for manufacturing a headrest, and more particularly to a method for rationally manufacturing a headrest with an excellent appearance.

(Description of Prior Art) Headrests are installed in almost all vehicles for the purpose of preventing occupants from suffering whiplash injuries in the event of a collision. The structure of the headrest is that a reinforcing body made of metal or synthetic resin that is integrated with the stay that fixes the headrest to the seat is covered with soft or semi-hard polyurethane foam, and this soft or semi-hard polyurethane foam is made of vinyl chloride resin, etc. It is covered with a skin material made of plastic leather or fabric whose back side is lined with a vinyl chloride resin sheet or the like.

As shown in Figures 1 to 6, the conventional manufacturing method for a headrest with such a structure is to cut a linear cut into the bottom of a skin material that is hollow inside and pre-shaped into the outer shape of the headrest. Include 41, <9 without 2. Alternatively, valve-shaped notches 6 are formed, these are used as injection ports, and a soft or semi-rigid polyurethane foam raw material is injected into the interior through the injection ports and foamed. However, with this conventional method, raw materials tend to adhere to the outside of the skin material around the injection port when the raw materials are injected, and many raw materials leak out from the injection port during foaming, so these must be removed by post-processing after molding. Furthermore, in order to facilitate subsequent processing, a release agent must be applied to the skin material and around the injection port of the skin material prior to the injection of raw materials, and around the injection port of the mold where the skin material is set during foaming. This required a lot of effort to manufacture.

Further, even after foam molding, the above-mentioned mold release agent adhering to the surface of the skin material had to be removed using a solvent. Furthermore, even in headrests that have been foam-molded, the mold release agent applied to the raw materials often adheres to the inner surface of the skin material, making it easy for the skin material to separate from the polyurethane foam, causing the skin material to peel off during use. It was raised and looked unsightly, and in the area where the raw material was injected, the skin material 4 was bent inward as shown by A in the cross-sectional view of Figure 4, creating a step and exposing the polyurethane foam, which was not desirable in terms of appearance. . In addition, 5 is a stay and 6 is a reinforcement body.

(Object of the Invention) The present invention was made in order to eliminate the above-mentioned problems that the prior art had, and aims to provide a method for rationally manufacturing a headrest with an excellent appearance.

(Structure of the Invention) The present invention uses a skin material having an open injection port that protrudes to the outside, injects polyurethane foam raw material into the interior of the skin material through the injection port, closes the injection port after injection, and closes the polyurethane foam raw material. This is a manufacturing method in which the headrest is obtained by foaming the foam and then cutting out the injection port.

The present invention will be explained in detail below using the accompanying drawings.

FIG. 5 is a perspective view of the skin material 7 used in the present invention, and shows an embodiment. The skin material 7 is formed by a slush molding method using a thermoplastic synthetic resin paste containing % vinyl chloride resin paste, or by melting thermoplastic synthetic resin powder in a molding hood to form a thermoplastic synthetic resin layer that conforms to the inner surface shape of the mold. The headrest is formed into a headrest shape by a molding method or by a blow molding method in which a tube is extruded from an extruder, the material is immediately sandwiched between after-effects, and air is blown inside to form a hollow product. part, preferably at the bottom which does not spoil the appearance, protrudes outward,
It has an opening 6- inlet 7a through which the inside and outside communicate. ! Mj: A pipe-shaped or rod-shaped stay, and the end of the stay 5 located inside the skin material 7 is reinforced with a reinforcing body (not shown) made of plastic or metal.
is combined with The stay 5 and the reinforcing body are installed in the skin material 7 by being set in the mold of the skin material 7 when the skin material 7 is molded, or by cutting a part of the skin material 7 open after the skin material 7 is molded. Inserted inside the skin material.

6 to 8 show the molding process of the present invention, and are sectional views taken along the dividing plane of the molding certificate. The molding process will be explained according to these figures.

(1) Injection of polyurethane foam raw material (Fig. 6) The injection lower a protruding to the outside aligns the skin material 7, the decorative body 6 and the stay 5 located inside the skin material 7, along the outer shape of the headrest. Set in the split molding W8 having a cavity, and pour the polyurethane foam raw material 9 from the injection lower a.
Inject a predetermined amount of a. The reinforcing body 6 is made of a hollow plastic product or a plate-shaped body made of plastic or metal.

The polyurethane foam raw material is appropriately mixed depending on the required physical properties of the head rest, such as hardness.

(2) Closing the injection port 6'1 (FIG. 7) After injection of the polyurethane foam raw material 9a, the injection lower a of the skin material 7 is closed using a pinch valve (not shown) or the like. The closing timing of the injection lower a is determined by the shape of the headrest, the material, shape or position of the stay and reinforcing body, and molding conditions such as the polyurethane foam, the blend of raw materials, and the temperature of the mold.

(3) Cutting out the injection port (Fig. 8) The entire polyurethane foam 9 is formed by foaming the polyurethane foam raw material, and after a predetermined period of time, the molded product is demolded, and the skin material 7 is injected into the 175 part using a cutting tool 10 such as a knife. is cut out and used as the final product. The mold temperature of the molding m8 is maintained at a temperature that optimizes the reaction of the polyurethane foam raw material from the time when the polyurethane foam raw material is injected until the molded product is decomposed.

FIG. 9 is a perspective view of the headrest obtained in this way, and 7b is a cutout of the injection port.

10 to 12 are partial perspective views and partially cutaway perspective views showing the types of injection ports.

The injection port 11 has an A"4i funnel shape with an enlarged injection tip, the injection port 12Fi has a flat part 12ae with a film gate facing down, and the injection port 13 has an enlarged funnel-shaped tip and is configured to form this injection port. It has a fitting part 13a that can be fitted to a type 1 holder.

(Effects of the Invention) As described above, the present invention injects polyurethane foam raw material into the skin material through the injection port formed in the skin material and protruding to the outside, and closes the injection port after injection of the raw material to foam the polyurethane foam raw material. Finally, the skin material and polyurethane foam are cut off at the injection port part of the skin material to obtain the headrest.

Therefore, according to the present invention, when the polyurethane foam raw material is injected, the raw material does not adhere to the skin material and the mold.
jllll'! There is no need for post-processing to apply a lil agent or remove adhered raw materials, and there is no risk of raw materials leaking out during foaming, so there is no need to remove the polyurethane foam on the outside of the skin material that is formed due to leakage. can be manufactured rationally. Furthermore, since the manufacturing method of the present invention does not use a release agent, there is no separation of the skin material from the polyurethane foam due to adhesion of the Qffi agent to the inner surface of the skin material, and there is no possibility that the skin material is bent inward when raw materials are injected. Since there are no steps, it is possible to obtain a plain appearance with no steps at the raw material injection part, and the resulting headrest has an excellent appearance.

[Brief explanation of the drawing]

Figures 1 to 4 relate to the conventional manufacturing method, Figures 1 to 6 are perspective views explaining the injection port, Figure 4 is a sectional view of the headrest, and Figures 5 to 12 relate to the present invention. , 5th
The figure is a perspective view illustrating one embodiment of the skin material, FIGS. 6 to 8 are sectional views illustrating the molding process, FIG. 9 is a perspective view of a headrest manufactured according to the present invention, and FIGS. Figure 12 explains the types of injection ports, Figures 10 and 11
The figure is a partial perspective view, and FIG. 12 is a partial perspective view with a part cut away. 7- 7...Skin material, 7a...Injection port, 9a"...Polyurethane foam [material, 9...Polyurethane foam, 10...Resecting tool patent applicant Inoue MCP Co., Ltd. 8- No. 1 Size [F], fan fence

Claims (1)

[Claims] Using a headrest-shaped skin material that protrudes to the outside and has an open inlet, the polyurethane foam raw material is injected into the skin material through the injection port, and this injection port is closed. A method for manufacturing a headrest, characterized by cutting it out.