JPS5845939A - Manufacture of rubber product - Google Patents

Abstract

PURPOSE:To enable the manufacture of a rubber product having a cylindrical shape opened at both ends or a bellow-shaped sectional shape by introducing hydraulic pressure between the product formed between an outer die and a core die, and the core die and then extruding the core die from the product. CONSTITUTION:When a slab-shaped crude rubber R is placed on the butting surfaces between a lower outer die 2 and an upper outer die 4 and the die 2 is raised by a ram cylinder, the rubber R is compressed between the upper outer die and the lower outer die, is intruded into an air gap 11 formed between the dies 2, 4 and a core die 5, and is formed in a bladder shape. Then, the crude rubber is vulcanized by the vapor heat which is introduced into the die 5 and air gaps 2a, 4a of the upper and lower outer dies. After the bladder B is vulcanized in this manner, pneumatic pressure is introduced between the bladder and the core die upon extruding of the die 5, and the core die is extruded in the state that the bladder is expanded. As a result, the opened end of the bladder is not damaged, but the bladder adapted for a radial tire having an outer diameter larger than the bore of the open end can be manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cylindrical or lantern-like cross-sectional shape with both ends open, which is used for curing tires, for example.
The present invention relates to a method for manufacturing aluminum products such as /, Ili, etc.

The above-mentioned burata is produced by pressing a comb between an outer mold and an inner core mold in a so-called burata press. Molded and vulcanized.

However, after the completion of molding and vulcanization: the core mold is pulled out from the bracket (representing the diameter of the opening end of the bracket) and forcibly pulled out while being mechanically pulled out by the mold (because it is necessary to
It is impossible to make the outer diameter of the outer diameter of the outer diameter of the outer diameter of the outer diameter of the outer diameter of the outer diameter of the outer diameter of the outer diameter of the outer diameter of the outer diameter of the inner diameter larger. was there.

On the other hand, in the case of radial tires, as shown in No. 60,
The raw tire has a shape that closely resembles the finished tire shape,
In order to achieve uniform vulcanization, it is desirable to have a shape that approximates the shape of a green tire and to reduce the elongation rate of the tire.
It is better to make the outer diameter of the burra as thick as possible, but as mentioned above, there is an eye limit to making the outer diameter of the burra as thick as possible, so only the burrata with the shape shown in Figure 4 can be manufactured. Improvement is desired.

The present invention has been proposed in view of the above-mentioned points, and its object is to provide rubber having a cylindrical or lantern-like cross-sectional shape with two open ends, such as a bra, with a significantly large outer diameter at the open end. An object of the present invention is to provide a method for manufacturing a product.

The present invention relates to a method for manufacturing a rubber product having a conical or lantern-like cross-sectional shape with both ends open.

1. After molding the product in the gap between the outer mold and the inner core mold, the core mold is pulled out from the product (at this time, one open end is held tightly and the core mold is removed from the core mold). Introducing fluid pressure between the product and the product to inflate the product, and then
The core mold is pulled out from the product.

As mentioned above, when the inner core mold is pulled out, the rubber product is inflated by fluid pressure, the open end is expanded, and the core mold can be pulled out. It is possible to manufacture large rubber products with a large outer diameter.

In Figures 1 to 5, 2 is the lower mold.

It is attached to the component 1 and moves up and down. 4 is a rising mold which is attached to the fixed upper constituent member 5 of the Burata press, and the upper and lower life molds 2 and 4 are secessarily signed by the upper end outer circumferential guide 2b of the lower outer mold fJ2.55 is an inner core mold; It can be raised and lowered with respect to the rising mold 4 by a known mechanism (not shown), and when rising, it is positioned in the rising mold 4 by the center taper 5 and also in the internal cavity.

Steam introduction pipe6. Drain pipe7. The pneumatic pipe 8 that penetrates the core metal and the lower part of the mold is installed (swiped).

Reference numeral 9 denotes an upper clasp fitting that fits into the center of the lower part of the core mold 5 with a taper; 10 denotes a lower clasp fitting that fits with the center hole taper of the lower die 2; 9 and 10 are configured to be able to be raised and lowered independently of each other by a cylinder mechanism (not shown) provided inside the pusher press ram cylinder.

Then, the upper and lower outer molds 2, 4. By pushing a comb into the empty PJil formed between the core mold 5 and the upper and lower Clasilla metal fittings 9 and 10, the Brata B is molded and vulcanized.

Note that sealed gaps 2 m and 4 m are formed in the upper and lower molds 2° 4 for heating for vulcanization, through which steam is introduced.

Assume that vulcanization is completed in the state shown in FIG. 1, lower the lower life mold 2 by the ram cylinder, and at the same time move the core mold 5 to the upper and outer molds. ! ! Lower it from 14. On the other hand, the upper and lower clamp fittings 9 and 10 are given a relative upward force by the lower external force type 2 so as to maintain a state in close contact with the core metal ms, as shown on the left side of Figure 2. .

Here, when air pressure is introduced from the pneumatic pipe 8 while the upper and lower crushing fittings 9 and 10 are held in close contact, the air pressure is applied to a small amount between the lower part of the core mold 5 and the upper crushing fitting 9. When the core mold 5 and plastic plate B are expanded from the gap as described above, the upper open end of the plastic plate B is expanded, and when the core mold 5 is raised in this state, the core mold 5 moves to the right side in Fig. 2. As shown, do not rub too much the upper am end of the upper heptera from the upper open end of the bulata B (it will be pulled out smoothly).

Thereafter, the lower crushing metal fitting 10 is lowered to the lower mold 2 as shown on the left side of FIG.

Next, as shown on the right side of Fig. 3, the slab-like raw rubber R is placed on the mating surface of the lower mold 4 of the upper mold 2, and the lower mold 2 is raised by a ram sill and a lever.・Compressed between the lower and outer molds.

The core metal i5 is pushed into the gap 11 formed between the upper and lower molds 2 and 4 and the core mold 5, and is formed into a zigzag shape.
It is vulcanized by steam heating introduced into the voids 2a, 4& of the inner, upper and lower molds.

As described above, when pulling out the core mold 5 after vulcanizing B, pneumatic pressure is introduced between the burr and the mold A to inflate the burr, and the expansion force of the open end causes the burr to expand. Since the core mold is pulled out in a fully expanded state for 5K, there is no risk of damaging the open end of the tire, and it is suitable for use with radial tires such as those shown in Figure 5, which have a larger outer diameter than the open end diameter. A suitable burrata can be manufactured.

Incidentally, in the conventional model, the lower crushing fitting is integrated with the lower outer mold, so in order to seal the open end of one of the thrusters for introducing air pressure, the plunger must be inserted into the lower outer mold. This must be carried out under certain conditions, but in this case, the expanded bladder will be strongly pressed against the upper corner of the lower outer mold.

This cannot be carried out due to the risk of damage to the bra, and the method described above (
, it is necessary to enable the lower classical fitting 10 to be raised and lowered relative to the lower outer mold 2.

The ratio of the open end diameter dI and the outer diameter D1 of the opening end is 1:15.
However, in the above embodiment, as shown in FIG. 5, the ratio of dI and Dl was up to 1:2.

In addition, the lower open end diameter d! of the bracket B may be not only df:dI but also df(dI).

Although the above description has been made regarding the production of tie P vulcanization plates, the present invention can be broadly applied to the production of other products having similar cylindrical or lantern-like cross-sectional shapes.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an example of the device used to carry out the present invention, FIGS. 2 and 5 are cross-sectional views showing different states between the left half and the right half, respectively, to explain the operating state, and FIGS. FIG. 5 is a diagram showing different shapes of tires, and FIG. 6 is a diagram showing the raw tire shape of the radial tie P. - B: Plata, 2: Lower outer mold, 4: Upper outer mold. , Ha4 Sentoku 6 Sen

Claims (1)

[Claims] A method for manufacturing a product having a cylindrical or lantern-like cross-sectional shape with both ends open, after the product is molded in a gap between an outer mold and an inner core mold. When pulling out the core mold from the product, one open end is held hermetically and fluid pressure is introduced between the A4i mold and the product to swell and erode the product. After that, the core mold is pulled out from the product.