JPH0217863Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Industrial application field] This invention relates to diaphragm molds, in particular,
The present invention relates to a mold for forming a diaphragm containing a base fabric.

[Prior art]

Generally, when manufacturing diaphragms containing base fabric, if the base fabric is placed directly in the diaphragm mold and molded, wrinkles will occur in the base fabric and the quality of the diaphragm after molding will deteriorate. Therefore, in order to prevent the base fabric from wrinkling, a base fabric preforming process was required.

[Problem that the invention attempts to solve]

However, in the case of the above-mentioned conventional products, a base fabric preforming process is required to prevent wrinkles in the base fabric, which lengthens the manufacturing period of the product, that is, the diaphragm containing the base fabric, and increases the manufacturing time. This also has the problem of increasing costs.

This invention solves the problems of the conventional ones as mentioned above, and it can be used directly with unvulcanized rubber without requiring a preforming process for the base fabric to prevent wrinkles in the base fabric. It is possible to shorten the manufacturing period by molding into
It is an object of the present invention to provide a diaphragm mold that can reduce manufacturing costs.

[Means for solving problems]

In order to solve the above problems, this invention includes an upper mold, a lower mold forming a molding cavity between the upper mold, and a lower mold disposed between the upper mold and the lower mold to a medium size for holding the base fabric outside the cavity;
The upper mold is provided with a biasing member that resiliently presses the middle mold against the lower mold before the molding cavity is formed by the upper mold and the lower mold.

[Effect]

By adopting the above-mentioned means, this idea
When molding a diaphragm, first, the base fabric surrounding the outside of the molding cavity formed by the upper and lower molds is pulled by the biasing member to prevent wrinkles from forming therein, and then Since forming is performed, even if the base fabric is not preformed, wrinkles will not occur in the base fabric after the diaphragm is formed.

〔Example〕

Embodiments of this invention shown in the drawings will be described below.

FIG. 1 and FIG. 2 show an embodiment of a diaphragm mold according to this invention, and this diaphragm mold includes a lower mold 2 and an upper part located above the lower mold 2 that is movable up and down. It consists of a mold 1 and a middle mold 3 located between the upper mold 1 and the lower mold 2.

The middle mold 3 has an annular shape that can come into contact with the bottom of an annular groove 2a formed on the upper surface of the lower mold 2, and a vertical hole 4 is bored in the part of the upper mold 1 facing the groove 2a. A spring holder 6 is provided in the hole 4, the rear end of which is located in the small diameter portion 4a of the hole 4, and a stop ring 5 is provided at the end to prevent downward movement. The lower end of the spring holder 6 is integrally formed with an enlarged portion 6a that comes into contact with the upper surface of the medium mold 3, and the spring 7 that winds the spring holder 6 always moves the spring holder 6 downward as shown in FIG. It is biased to the position. Therefore,
The spring holder 6 and the spring holder 6
A biasing member is constituted by a spring 7 that presses the spring 7 toward the medium mold 3 and a stop ring 5 that preloads the spring 7.

During molding, an unvulcanized rubber 8 is provided in the center of the lower mold 2 that cooperates with the upper mold to form a molding cavity, and a base fabric 9 is placed so as to cover the upper surface of the unvulcanized rubber 8. After doing this, when the middle mold is lowered, the middle mold 3 falls into the groove 2a of the lower mold 2.
Moreover, since the middle mold 2 is annular along the outer edge of the base fabric 9, the outer edge of the base fabric 9 is not held between the middle mold 3 and the lower mold 2. Become.

Next, when the upper die 1 is lowered, the enlarged part 6a of the spring holder 6 comes into contact with the upper surface of the middle die 3, and when the upper die 1 is further lowered, the enlarged part 6a of the spring holder 6 is brought into contact with the middle die 2. The biasing force of the spring 7, that is, the spring load acts on the base fabric 9 to provide a suitable tension, which acts on the base fabric 9.

In this way, with the base fabric 9 given an appropriate tension, the inner diameter portion 1a of the upper mold 1 is applied to the lower mold 2.
The base fabric 9 is squeezed between the base fabric 9 and the upper die 1 and the lower die 2 are completely closed, and vulcanization is performed as shown in FIG. 2 to form a diaphragm 10 containing the base fabric. .

3 and 4 show another embodiment of this invention, in which a mold formed substantially the same as that of the previous embodiment is used to form a base fabric. The case where preforming is performed is shown,
Parts that are substantially the same as those in the embodiment described above are given the same numbers, and explanations thereof will be omitted.

Even when preforming the base fabric 9 using the mold of this embodiment, the force of the spring 6, that is, the spring load allows the deep drawing base fabric to be preformed without wrinkles. In addition, the diaphragm can also be integrally molded using the base fabric and unvulcanized rubber as in the above embodiment.

In each of the above embodiments, an annular recess, which is a groove, is formed on the upper surface of the lower mold that surrounds the outside of the portion of the lower mold that cooperates with the upper mold to form the molding cavity. Although the description has been made regarding the case where the medium size is located within the
The upper surface of the outer side of the molding cavity of the lower mold is flattened, and the middle mold is brought into contact with this upper surface, and the base fabric is elastically pressed between the lower mold and the middle mold by a biasing member. However, it is of course possible to prevent wrinkles from forming in the base fabric during molding.

[Effect of idea]

By configuring this idea as described above,
By elastically pressing the outer periphery of the base fabric with a medium mold that is biased by a biasing member before molding, it is possible to prevent wrinkles from forming when molding with unvulcanized rubber. Since it can be molded directly with unvulcanized rubber without requiring preforming of the base fabric to prevent fabric wrinkles, it is possible to shorten the manufacturing period and reduce manufacturing costs. It has excellent effects such as being able to

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing the diaphragm mold according to this invention before operation, Figure 2 is a schematic diagram showing the diaphragm mold of Figure 1 in operation, and Figure 3 is a diagram showing the preforming of the base fabric. FIG. 4 is a schematic diagram showing the state shown in FIG. 3 before operation. 1... Upper mold, 1a... Inner diameter part, 2... Lower mold, 3
... Medium size, 4 ... Hole, 4a ... Small diameter part, 5 ... Stop ring, 6 ... Spring holder, 7 ...
Spring, 8... Unvulcanized rubber, 9... Base fabric, 1
0...Diaphragm with base fabric.

Claims (1)

[Scope of utility model registration request] An upper mold 1, a lower mold 2 forming a molding cavity between the upper mold 1, and a base fabric disposed between the upper mold 1 and the lower mold 2 to form a base fabric outside the molding cavity. a middle mold 3 for holding the middle mold 3, and the middle mold 3 is attached to the lower mold 2 before forming the molding cavity with the upper mold 1 and the lower mold 2.
The biasing members 5, 6, and 7 that press the upper mold
A diaphragm mold characterized by being arranged in.