JPH07171834A - Mold for producing tire vulcanizing bladder - Google Patents

Abstract

PURPOSE:To provide a mold capable of easily producing a bladder capable of corresponding individually to every kind of a tire by altering gauge distribution. CONSTITUTION:In a mold for producing a tire vulcanizing bladder constituted by combining ring-shaped outer molds 1, 2 and a ring-shaped core 3, the ring- shaped core 3 is constituted of a large number of small parts 41, 42... divided in axial and peripheral directions and the gauge distribution of the bladder can be altered by replacing the small parts 41, 42....

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to dies for making bladders used in the vulcanization process in all tire types.

[0002]

2. Description of the Related Art A conventional mold used for manufacturing a bladder comprises a ring-shaped outer mold and a middle mold, and the shape and gauge distribution (thickness distribution) of the bladder are determined by the initially designed shapes of the outer mold and the middle mold. To be done.

FIG. 1 is a view showing a cross section of a conventional mold for manufacturing a bladder. The ring-shaped outer mold is composed of an upper outer mold 01 and a lower outer mold 02 which are divided into upper and lower (axial directions) approximately half and half. The annular middle mold is also divided into upper and lower molds, but the upper middle mold 03 Occupies a larger area than the lower middle size 04,
The inside of the upper middle mold 03 is a heating medium chamber 05. The bladder 06 is manufactured by supplying synthetic rubber to the inside of a mold configured by combining the outer molds 01, 02 and the middle molds 03, 04.

The shape and gauge distribution of the manufactured bladder 06 are determined by these four molds 01, 02, 03, 04. When changing the normal gauge distribution, it is not possible to deal with it except by replacing the medium size 03, 04. Therefore, when changing the gauge, manufacture the entire medium size according to the change,
I was trying to replace the entire medium size.

In this way, it is difficult to manufacture a medium-sized tire each time the gauge is changed, and it is therefore difficult to prepare a bladder corresponding to each tire type. Therefore, in reality, many types of tires are manufactured by one type of bladder.

[0006]

[Problems to be solved] As described above, the bladder cannot be individually adapted for each type of tire. Therefore, when it is desired to change the gauge distribution of the bladder for the purpose of temperature control of each part of the tire, it is necessary to change the tire inner surface during vulcanization Flexible and quick when you want to change the bladder expansion form so that air escapes well for the purpose of preventing air retention, or when you want to partially change the gauge distribution to deal with the failure that the bladder is partially damaged due to rubber deterioration. Can not correspond to.

The present invention has been made in view of the above points,
The purpose of this is to provide a bladder manufacturing mold for tire vulcanization that can easily manufacture a bladder that can be individually adapted for each type of tire by changing the gauge distribution.

[0008]

In order to achieve the above object, the present invention relates to a mold for producing a tire vulcanizing bladder, which is constituted by combining an annular outer mold and a middle mold. A mold for manufacturing a bladder for tire vulcanization in which a ring-shaped middle mold is composed of a plurality of small parts divided in the axial direction and the circumferential direction, and the gauge distribution of the bladder can be changed by exchanging the small parts.

Since it is possible to easily obtain the desired gauge distribution of the bladder by replacing only the small parts of the portion requiring the gauge change of the medium size, it is possible to easily manufacture the bladder which can be individually adapted to each tire type. it can.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention shown in FIGS. 2 and 3 will be described below. The outer die is composed of an upper outer die 1 and a lower outer die 2 which are divided into upper and lower halves as in the conventional example. On the other hand, the middle die 3 is configured by combining a plurality of small parts that are divided into a plurality of circumferentially and axially opposed inner peripheral surfaces of the outer dies 1 and 2, and is divided into 14 in the circumferential direction in FIG. The small parts 4 ₁ , 4 ₂ , ..., 4 ₁₄ are shown.

The small parts 4 ₁ , 4 ₂ , ..., 4 ₁₄ are supported by the upper middle-size support member 5 and the lower middle-size support member 6, and the upper middle-size support member 5 and the lower middle-size support member 5 are supported. The member 6 is a part of the middle dies 03, 04 of the conventional example, and the heating medium chamber 7 is provided inside the upper middle dies supporting member 5. The upper middle-sized support member 5 is composed of the upper 11 small parts 4 ₁ ,
4 _2, ..., 4 ₁₁ support, the lower middle- supporting member 6 is adapted to support three small parts 4 _12, 4 _13, 4 ₁₄ lower.

A dovetail groove oriented in the circumferential direction is formed on the side of the medium-sized supporting members 5 and 6, and a corresponding ridge is formed on the side of the small components 4 ₁ , 4 ₂ , ..., 4 ₁₄ respectively. The ridges of the small parts 4 ₁ , 4 ₂ , ..., 4 ₁₄ are fitted in the dovetail grooves of the members 5, 6 so that the small parts 4 ₁ , 4 ₂ , ..., 4 ₁₄ are supported by the medium-sized support members 5, 6. It

The bladder 10 is manufactured by supplying synthetic rubber between the small parts 4 ₁ , 4 ₂ , ..., 4 ₁₄ and the outer molds 1, ₂ supported by the middle mold supporting members 5, 6. The bladder 10 is for tire vulcanization, and is made of synthetic rubber, such as butyl rubber, which can be used for a long time under high temperature and high tension of about 200 ° C. during vulcanization.

The bladder 10 has an annular shape as a whole, and side parts 10b and 10c extend vertically from the center part 10a to the flange parts 10f and 10g through the neck parts 10d and 10e. The upper and lower flanges 10f and 10g are formed by the outer molds 1 and 2 and the middle mold supporting members 5 and 6, but the neck 10
d, outer mold 1 and the small parts 4 ₁ toward the center portion 10a from 10e, 4 _2, ..., is also determined gauge distribution with shape by 4 ₁₄ is determined.

The bladder manufacturing die of this embodiment has the structure as described above, and the gauge distribution can be obtained by exchanging the small parts 4 ₁ , 4 ₂ , ..., 4 ₁₄ partially or entirely. It can be changed easily. FIG. 3 shows small parts 4 ₁ ,
4 _2, ..., 4 ₁₄ by an illustration how the gauge distribution of the bladder 10 is changed, and the broken line shows a gauge change when replacing the neck 10d, small parts 4 _1, 4 ₁₄ closer to 10e only The side portions 10b and 10c near the neck portions 10d and 10e are partially thickened.

The alternate long and short dash line indicates the small part 4 of the center portion 10a.
An example of the gauge distribution when all other small parts except ₇ are replaced is shown. It is easy to make the side portion of the bladder 10 thicker or thinner if necessary. In this embodiment, the bladder 10 has a thickness of 0.1 mm to 2
It can be changed by 0.0mm.

As long as the same bladder is used, it is difficult to change and control the maximum temperature during tire vulcanization in parts. For example, the kind of tire and side part where the temperature of the bead part and side part is desired to be lowered. It is not possible to use the same bladder for the type of tire whose temperature you want to lower, and even in such a case, you can replace only some of the required small parts of the medium size 3 and easily and at low cost the desired bladder. Can be manufactured.

Further, even when the bladder expansion mode or gauge distribution is changed in order to solve a failure during use of the bladder, such as a manufacturing failure of the tire inner surface such as air remaining on the tire inner surface or a partial damage due to rubber deterioration, It is easy to deal individually and at low cost. Further, even when the outer mold has the same rim diameter and the outer mold has a different shape, it is possible to easily form the middle mold corresponding to the outer mold.

In this embodiment, the small parts 4 ₁ , 4 ₂ , ...,
Although it is between the medium-sized support members 5 and 6 to support 4 ₁₄ and the groove and the projection are fitted together, the small-sized support member 20 can be made smaller along the medium-sized support member 20 as partially shown in FIG. The components 21, 21, ... May be supported together by fitting the dovetail groove and the ridge. Also, the number of small parts by dividing the medium size can be appropriately determined as necessary, but in the division in the circumferential direction, 2 to
10 pieces, 4 to 20 pieces are suitable for axial division.

[0020]

According to the present invention, the desired gauge distribution of the bladder can be easily obtained by exchanging only the small parts of the medium-sized gauge that need to be changed, so that it is possible to deal with each type of tire individually. The bladder can be easily manufactured.

[Brief description of drawings]

FIG. 1 is a sectional view of a conventional bladder manufacturing mold.

FIG. 2 is a cross-sectional view of a mold for manufacturing a bladder according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a relationship between small parts and a bladder.

FIG. 4 is a sectional view of an essential part showing another structure for supporting small parts.

[Explanation of symbols]

1 ... Upper outer mold, 2 ... Lower outer mold, 3 ... Medium mold, 4 ₁ , 4 ₂ ,
..., 4 ₁₄ ... small parts, 5 ... upper middle-sized supporting member, 6 ... lower middle-sized supporting member, 7 ... heating medium chamber, 10 ... bladder, 20 ... middle-sized supporting member, 21 ... small parts.

Claims (1)

[Claims] 1. A mold for manufacturing a bladder for tire vulcanization, which is configured by combining an annular outer mold and a middle mold, wherein a plurality of small parts are formed by dividing the annular middle mold in an axial direction and a circumferential direction. A mold for manufacturing a bladder for tire vulcanization, characterized in that the gage distribution of the bladder can be changed by replacing the small parts.