JPH0440184B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and a mold for forming a diaphragm containing a base fabric.

Conventionally, molds as shown in Figs. 1 to 3 have been known as molds for fabric-filled diaphragms, and include a diaphragm-shaped lumen e formed by an upper mold a and a lower mold b, and its The diaphragm e formed with a burr cavity d around the periphery and formed by these molds has a base fabric f located on one side of the diaphragm e, as shown in FIGS. 4 to 6, respectively. At the flange part g on the outer periphery of the diaphragm e, the base fabric f is exposed on the flange sealing surface, and not only is the sealing performance of the diaphragm e poor, but the base fabric f
There were problems such as peeling of the film. However, in the conventional mold structure, no tensile force is applied to the base fabric f, so the base fabric
It has the fatal drawback that it cannot be buried deeply. Another commonly used method is to provide a protrusion on the a side of the upper die of the burr cavity d in Fig. 2, and press and hold the base fabric between it and the b side of the lower die through the rubber fabric. There is a method, but if the base fabric contacts the flange g before the protrusion, or the base fabric cannot be held sufficiently because the rubber fabric is interposed, wrinkles of the base fabric may appear on the inner circumferential side of the diaphragm flange. This also causes problems such as the inability to embed the base fabric within the diaphragm, and it is still not possible to solve the adverse effects on the bonding of the base fabric to the diaphragm. Therefore, there has been a need for a diaphragm molding method and mold that can embed the base fabric of a diaphragm containing base fabric into the thickness of the flange portion.

In view of the above problems, an object of the present invention is to provide a method for molding a diaphragm that allows the base fabric of a diaphragm containing base fabric to be buried sufficiently deeply into the wall thickness of a flange portion, and also to provide a mold for the same. The purpose is to

In order to achieve the above object, the molding method of the present invention is a molding method in which a diaphragm having a flange portion on the outer peripheral edge and a base fabric are integrally molded. At the same time, a pair of split molds having a concave ring on one burr-forming surface and a convex ring on the other burr-forming surface that protrudes into the gap that forms a burr when corresponding to the concave ring. The method for forming a diaphragm includes placing the fabric, placing a base fabric on one side of the rubber-like fabric, clamping a pair of split molds to form the diaphragm, and then separating and forming the burr part. .

In addition, the molding die of the present invention is a pair of split molds for forming a diaphragm by embedding a base fabric from one side in a rubber-like elastic material fabric, and a flange is provided on the diaphragm-shaped inner cavity and the outer peripheral edge of the diaphragm-shaped inner cavity. and a molded surface forming a burr cavity on the outer peripheral edge of the flange part, one molded surface of the burr cavity has a convex ring, and the other molded surface corresponds to the formed surface of the convex ring. It has a convex ring that protrudes into the gap that forms a burr when it does so.

Hereinafter, embodiments of the diaphragm mold of the present invention will be described with reference to the drawings. FIGS. 7 to 9 show molds having different shapes of the flange cavity 4, respectively. In each figure, the mold has a pair of split molds 1 and 2 that are moved toward and away from each other, and a diaphragm-shaped lumen 3 is provided at the junction of the split dies 1 and 2, and the diaphragm-shaped lumen 3 A thick flange cavity 4 is provided as part of the outer peripheral edge of the flange cavity 4, a burr cavity 5 is provided on the outer periphery of the flange cavity 4, and the inner surface of the burr cavity 5 of the one split mold 1, 2 A concave annulus 6 is provided on the other split molds 1 and 2, and a convex annulus 7 that enters the concave annulus 6 prior to completion of mold clamping is provided.

As shown in FIGS. 10 to 12, the diaphragm molded by the mold having the above configuration has the base cloth 11 located within the wall thickness of the diaphragm 10, and the base cloth 11 is located within the wall thickness of the diaphragm 10, especially at the flange portion 12. 11 diagonally crosses its cross section, the base fabric 11 is located deep inside the diaphragm 10 and does not appear on the flange surface.The diaphragm 10 using this mold is described below. The molding method will be explained.

The diaphragm 10 containing the base fabric can be molded using the above-mentioned mold. There are two methods: first forming the rubber fabric into a product shape (with burrs), then filling it with the base fabric and press-forming; and another method of forming the rubber fabric into a sheet shape. There are two methods in which the rubber fabric and the base fabric are simultaneously put into a mold and pressure-molded. An example of the former method will be explained with reference to FIGS. 13 and 14.

The rubber fabric 13 preformed into a product (with burrs) shape using the mold is attached to the lower split mold 2 when the mold is opened, and the base fabric 1 is placed on top of the rubber fabric 13.
The diaphragm 10 is pressure-molded by placing the mold and clamping the mold again. Taking advantage of the fact that the convex ring line 7 enters the concave ring line 6 prior to completion of mold clamping, the convex ring line 7 is 7, the outer peripheral edge of the base fabric 11 is pulled in a direction in which a part of the base fabric 11 is embedded in the corresponding portion of the flange portion 12 of the rubber fabric 13, thereby causing the base fabric 11 to form a flange. Part 12
Pull it into the wall thickness. After molding, the mold is released and the burr portion 14 is cut and removed together with the base fabric 11 extending thereto.

The diaphragm molding method of the present invention has the following effects. That is, ○A. The convex ring strip enters the concave ring strip of the split type and presses the base fabric, so it effectively applies tension to the base fabric, pushes it into the flange part, and securely embeds the base fabric inside the diaphragm. be able to. At the same time, the concave ring and convex ring effectively restrict the flow from the diaphragm-shaped inner cavity of the rubber fabric to the burr cavity, allowing the rubber fabric to flow into the base fabric, causing the base fabric to flow. It can be buried within a uniform thickness inside the diaphragm. When cutting the burr part from the diaphragm, the flange part and the bent part formed by the convex ring can be held in the cutting jig. It becomes possible to accurately cut a predetermined position on the outer circumferential side of the flange portion. Therefore, there is no variation in the mounting position of the diaphragm to the housing, and when the diaphragm is mounted, the operating characteristics as set can be obtained.

○C The concave ring and convex ring of the split type effectively restrict the outflow of the rubber fabric to the burr side, which exerts the compression effect of the diaphragm and improves the material strength by modifying the material. be able to.

Next, the mold of the present invention has the following effects.

The effects of ○a and ○b above also occur depending on the mold.

In particular, pressing the base fabric using a combination of the split type concave ring and convex ring has the effect of embedding the base fabric deeper into the flange than the inner diameter side portion of the flange.

When the flange part is attached to the mounting part of the housing, the base fabric is not exposed to the outside surface, so it has the effect of sealing, and the base fabric of the flexible part is closer to one side of the diaphragm than the housing part. Since it can be buried shallowly, the placement of this base fabric on one side has the effect of improving the operating characteristics of the diaphragm when pressure is applied to the other side.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIGS. 1 to 3 are half-cut sectional views showing the structure of a conventional mold, and FIG. 4A shows a mold formed by the mold shown in FIG. A half-cut sectional view of the diaphragm, FIG. 4B is an enlarged sectional view of the same essential part, and FIGS. 5 and 6 are enlarged sectional views of the essential part of the diaphragm molded by the molds shown in FIGS. 2 and 3, respectively. 7 to 9 are half-cut sectional views showing the mold of the present invention, and FIG.
Figure 0A is a half-cut sectional view of the diaphragm molded by the mold shown in Figure 7, Figure 10B is an enlarged sectional view of the same essential parts, and Figures 11 and 12 are Figures 8 and 9, respectively. FIG. 13 is an enlarged cross-sectional view of the main part of the diaphragm formed by the mold shown in the figure, and FIG.
FIG. 14 is a sectional view of the main part when the mold clamping is completed. 1, 2...divided type, 3...diaphragm-shaped inner cavity,
4... Flange cavity, 5... Burr cavity, 6... Concave ring strip,
7... Convex ring strip, 10... Diaphragm, 11... Base fabric,
12...flange part, 13...rubber fabric, 14...burr part.

Claims (1)

[Claims] 1. In a molding method in which a diaphragm 10 having a flange portion 12 on the outer peripheral edge and a base fabric 11 are integrally molded, a burr portion 1 is formed on the outer peripheral side of the flange portion 12.
4, the one burr forming surface has a concave ring 6, and the other burr forming surface has a burr 14 formed when the surface corresponds to the concave ring 6. Rubber fabric 13 is placed between a pair of split molds 1 and 2 having a convex ring 7 protruding into the gap to be formed.
At the same time, the base fabric 11 is placed on the other burr forming surface side of the rubber fabric 13 where the convex ring strip 7 is located, and the pair of split molds 1 and 2 are clamped to form a diaphragm. A method of forming a diaphragm by separating and forming a burr portion 14. 2 A base fabric is embedded in the rubber fabric from one side to form a diaphragm-shaped inner cavity 3 and the diaphragm-shaped inner cavity 3.
The flange portion 4 has a forming surface forming a burr cavity 5 on the outer periphery of the flange portion 4, and has a concave ring 6 on one forming surface of the burr cavity 5, and has a concave ring 6 on the other side. A mold for a diaphragm having a convex annular strip 7 projecting into a gap forming the burr portion 14 when the forming surface corresponds to the forming surface of the concave annular strip 6.