JPH06170870A - Manufacture of vinyl chloride hollow ball, in which substance is sealed - Google Patents

Abstract

PURPOSE:To obtain a hollow ball, excellent in appearance as well as quality and in which a substance is sealed, by a method wherein a hollow ball, made of semi-gelled vinyl chloride paste, is molded employing a rotary molding mold consisting of a top force and a bottom force, then, a molded form is divided into two parts together with the mold and adhesive paste is applied on the end faces thereof to clamp the mold while sealing the substance thereinto and effect rotary molding. CONSTITUTION:A rotary molding mold consisting of a top force 11 and a bottom force 10, whose inner surfaces are semi-spherical, is filled with vinyl chloride paste while the mold is heated and rotated to mold a hollow ball of semi-gelled or gelled condition. When the top force 11 is removed without cooling, the hollow ball is divided into two parts at a boundary between the top force 11 and the bottom force 10 whereby semi-spherical hollow balls A1, A2 can be obtained. Adhesive paste B is applied on the end faces and a substance C is placed in the inner part of the mold, then, the mold is clamped and the rotary molding is effected while heating the mold again. According to the method, the ball molding paste will never be adhered to the substance C sealed in the ball.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is manufactured by rotational molding.
The present invention relates to a method for manufacturing a hollow vinyl chloride ball in which an object such as a sensor or a bell is enclosed.

[0002]

2. Description of the Related Art In order to enclose an article such as a bell in a hollow ball molded by rotational molding, it is generally done in Japanese Examined Patent Publication No.
As disclosed in Japanese Patent Publication No. 0-31900, a pedestal is fixed to an inner wall of a molding die by a method such as adhesion, and an article or the like is attached to the pedestal. And is molded by rotational molding.

[0003]

By the way, according to the above method, when the vinyl chloride paste is rotationally molded on the article in the mold, a part of the paste adheres to the article, and the article is contaminated with the paste. , Depending on the attached paste,
There is a risk that the article will be stuck to the inner surface of the ball. Therefore,
An object of the present invention is to eliminate such defects of the conventional products.

[0004]

[Means for Solving the Problems] In order to solve the above-mentioned object, a method for producing a hollow vinyl chloride ball having an object enclosed therein according to the present invention is a vinyl chloride in a rotational molding die composed of an upper die and a lower die. A semi-gelled or gelled hollow ball is molded along the inner surface of the rotational molding die containing the paste, and then the upper mold or the lower mold is separated to adhere to the upper mold and the lower mold. The hollow ball is divided into two hemispherical parts along the upper mold and the lower mold, and then an adhesive paste having the same quality or excellent compatibility with the paste is attached to the end surface of the hollow ball divided into two parts. The present invention is characterized in that an object is internally provided inside, and then upper and lower molds are fitted to each other and rotational molding is performed.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a polyvinyl chloride for forming a ball, which is made of polyvinyl chloride, a plasticizer, an adhesive, etc., in a rotational molding die (1) having an inner surface of a hemispherical upper die (11) and a lower die (10). Spherical hollow balls (A) in a semi-gelled or gelled state, containing paste and heating the rotary mold (1) in a furnace (200 to 300 degrees) and rotating for 2 to 4 minutes.
The molded state is shown.

FIG. 2 shows a hemisphere which is taken out from the furnace shown in FIG. 1 and is not cooled with water, that is, without being cooled (normal temperature), and after removing the upper mold (10), the hemisphere is divided into two parts. The state in which the adhesive paste (B) is attached to the end faces of the hollow balls (A ₁ ) (A ₂ ) in the shape of a circle is shown.

When the upper die (11) is removed, the rotational molding die (1)
Is not cooled, the internal air swells, and the swelling output and the spherical hollow balls (A) are semi-gelled or gelled, so that the spherical hollow balls (A) have an upper mold (11) and a lower mold. From the boundary portion of (10), it is divided into two and becomes hemispherical, and adheres to the inner surfaces of the lower mold (10) and the upper mold (11), respectively.
In this state, placed a hollow ball (A ₁₎ (A ₂₎ object within (C), a hollow ball (A ₁₎ having an adhesive paste (B) to the end surface (A ₂₎ on the attached, the lower mold ( 10) (11)
When the mold is clamped, and the mixture is heated again to be rotationally molded, the hemispherical hollow balls (A ₁ ) (A ₂ ) in the rotational molding die are adhesive paste (B) as shown in FIGS. 3 and 4. To connect together.

The above-mentioned adhesive paste (B) is a resin paste having the same or excellent compatibility with the paste for molding the ball (A). After the second rotational molding, the rotational molding die is cooled with water, After the gelation, the mold is removed to produce the vinyl chloride hollow balls (A ') shown in FIG.

The above object (C) is a hollow ball (A ').
A urethane foam ball that has an outer diameter that is approximately the same as the inner diameter of, or a sensor built into this ball, or
When the ball body (A ') is a transparent body, it is an artificial flower or a bell, and the sensor is a sensor such as a magnetic sensor, and the hollow ball rolls by this sensor.
A timbre is generated.

[0010]

EFFECTS OF THE INVENTION According to the present invention, after a hollow ball is rotationally molded in a semi-gelled or gelled state by a rotational molding die, the rotational molding die composed of a lower die is separated without cooling. Then, a hemispherical two-part hollow ball along the upper and lower molds is molded, and an adhesive paste is attached to the end surface of the two-part hollow ball to be rotationally molded again. In addition, there is no risk that the ball forming paste will adhere. Therefore, the object is not contaminated by the ball-forming paste or attached to the inner wall surface of the ball. Therefore, the hollow ball made of vinyl chloride having excellent appearance quality and the like can be manufactured by simple manufacturing.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a state in which a semi-gelled or gelled ball is molded by the method according to the present invention.

FIG. 2 is a perspective view of the state in which the upper mold is released from the state of FIG.

FIG. 3 is a cross-sectional view showing a state in which an object is enclosed inside.

FIG. 4 is an enlarged view of part (a) of FIG.

FIG. 5 is a perspective view showing a hollow ball formed by the method of the present invention with a part thereof cut away.

[Explanation of symbols]

 1 Rotational mold A Semi-gelled or gelled hollow ball B Adhesive paste C Object

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area B29L 31:52 4F

Claims (1)

[Claims] 1. A semi-gelled or gelled hollow ball is formed along the inner surface of a rotational molding die by containing vinyl chloride paste in the rotational molding die composed of an upper die and an upper die. Alternatively, by separating the lower mold, the hollow ball attached to the upper mold and the lower mold is divided into two hemispherical shapes along the upper mold and the lower mold, and then the end faces of the two divided hollow balls. To
Adhesive paste having the same or excellent compatibility as the paste is attached, and after the object is internally housed therein, the upper and lower molds are fitted to each other and rotational molding is performed. Method for manufacturing vinyl hollow balls.