JPS6056517A - Manufacture of hollow body with insert therein - Google Patents

Abstract

PURPOSE:To mold simply a hollow body without necessity of the conventional process of cutting open by a method in which one part of an insert is positioned in the cavity of a split mold and the insert is kept at the fitting part of the split mold and then rotational molding is achieved. CONSTITUTION:An insert 3 is kept at the fitting part 2b of a split mold at the state where the part 3a of the insert is positioned in the cavity 2a of the split mold 2. The paste or the powder of thermoplastic resin e.g. PVC paste is poured into the cavity and the split molds 1, 2 are clamped and heated with rotation, whereby the gelatinized PVC layer is molded on the inner surface of the cavity. The skin material 6 of a head rest with the insert 3 therein is obtained by mold release after cooling. By this method, the conventional process of cutting open for fitting the insert becomes unnecessary, and simultaneously liquid cushion raw material does not leak outside.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a hollow body having an insert inside to be used as a skin material for a headrest stop.

(Description of the prior art) The production of products that have an insert inside and whose outer periphery is narrowed by a skin material, such as a headrest, has traditionally involved forming a bag-shaped skin material and then removing a part of this skin material. This was done by cutting open the skin, inserting an insert into the skin, injecting a synthetic resin foam material such as polyurethane foam through the opening of the skin, and foam-molding the cushioning material inside the skin. However, in such a method, the skin material must be cut open to insert the insert, which increases the number of work steps, and the synthetic resin foam raw material leaks from the cut-out part for insert insertion, resulting in leakage of the material to the outside. In order to form this, it is necessary to perform this deburring operation and to apply an l1li molding agent to facilitate the delinquent removal, which is not a rational method. Furthermore, the cutout portion for inserting the insert is visible, which is not aesthetically pleasing.

(Objective of the Invention) The present invention has been made in consideration of the above points, and provides a method for rationally manufacturing a hollow body having an insert inside, which is used as a skin material for a headrest stop.

(Structure of the Invention) The present invention utilizes a rotational molding method using vinyl chloride resin paste or powdered polyethylene, etc., which is often used in the production of hollow bodies made of thermoplastic synthetic resin. The purpose of the present invention is to carry out rotational molding by holding a portion of the insert in the split mold and holding the insert in the mating portion of the split mold.

The present invention will be specifically explained below using the drawings.

FIG. 1 is a perspective view illustrating an embodiment of the present invention.
This shows the manufacturing of headrest skin materials. The mold used in carrying out the present invention is a split mold consisting of an upper mold 1 and a lower mold 2, and has a cavity 1as2a that forms a predetermined shape of the skin material of the headrest when the mold is closed. This structure allows the insert 6 to be held in the mating portion 2b of the mold 2. The inserter also includes a portion 6a located within the skin material of the headrest and reinforcing the headrest;
It is composed of a stay part 6b that supports the headrest on the upper part of the seat. The hollow body having an insert inside, which becomes the skin material of the headrest, is made by holding the insert 6 in the mating part 2b of the split mold with a part 6a of the insert positioned inside the cavity of the split mold, and inserting the insert 6 into the cavity. Inject thermoplastic synthetic resin beneto or powder, for example, vinyl chloride resin paste 4a, close the split mold, and heat while rotating the split mold to form a gelled vinyl chloride resin layer on the inner surface of the cavity, Obtained by demolding after cooling. In addition, the split mold is Kufunbu 5.
The mold is closed by the mold, and a gas vent hole (not shown) is provided at a predetermined position of the split mold to allow gas generated in the cavity to escape. This gas vent hole can also be used as an injection port for a cushioning material forming compound when the cushioning material is continuously formed within the skin material after manufacturing the skin material.

FIG. 2 is a partially cut away perspective view of a headrest skin 6 having an insert therein manufactured in accordance with the present invention. The skin material 6 having an insert inside is integrated with the bag body 4 made of a thermoplastic synthetic resin with an inside made of the above-mentioned vinyl chloride resin paste, and a part 3a is inside the bag body 4. and an insert 6 located therein. In the part of the insert 6 that protrudes from the bag body 4, the periphery of the insert filter is sealed by the thermoplastic synthetic resin that constitutes the bag body 4, and when pouring the liquid cushion material raw material into the bag body 4, the raw material is There is no risk of leakage.

(Effects of the Invention) The present invention performs rotational molding by positioning a part of the insert in the cavity of the split mold as described above and holding the insert in a good condition at the mating part of the split mold. . Therefore, the resulting product has an insert inside, which eliminates the need for the post-cutting process for insert insertion, which was required in conventional manufacturing methods. Even if raw materials are injected, they cannot be returned to the outside. Furthermore, if the insert is held in a different way from the present invention, for example, by providing an insertion hole for holding the insert in one of the split molds and setting the insert in this insertion hole, setting the insert takes time and demolding is troublesome. Furthermore, repeated insertion of the insert will enlarge the insertion hole, making it difficult to secure the insert, and will also cause leakage of the cushion material raw material, which will require an increase in the deburring process.
The present invention does not cause the above-mentioned inconvenience because the insert is held at the mating portion of the split mold.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing one embodiment of the present invention, and FIG. 2 is a partially cutaway perspective view of the skin material of a headrest manufactured according to the present invention. 1... Upper mold, 2... Lower mold, 1a, 2a... Cavidigilito α i, 6... Benli=, 4... Vinyl chloride resin paste patent issuer Inoue MCHIP Co., Ltd. 1 Figure 5 Figure 2 91-

Claims (1)

[Claims] Holding the insert in the mating part of the split mold with a part of the insert positioned in the cavity of the split mold that forms a cavity of a predetermined shape when the mold is closed;
It is characterized by forming a hollow body within the cavity by a rotational molding method. A method for manufacturing a hollow body having an insert inside.