KR200227445Y1 - Rubber Band for MR Bladder Life Cycle Increasing - Google Patents

Abstract

The present invention relates to a rubber band for improving MR bladder life.

The rubber band for improving the life of MR bladder of the present invention is the aging of the MR bladder which transfers heat into the tire during molding into the mold to cure the green tire as a step before producing the finished tire in the tire industry. By attaching a rubber band to the curved portion of the bladder in which cracks are concentrated, the life of the bladder can be improved by suppressing the aging of the bladder and the occurrence of cracks.

Description

Rubber Band for MR Bladder Life Cycle Increasing

The present invention relates to a rubber band for improving MR bladder lifespan, and more specifically, a tire in the process of molding into a mold for vulcanizing the green tire as a step before producing the finished tire in the tire industry. By attaching a rubber band to the curved part of the bladder where aging or cracks of MR bladder heat transfer to the inside, it is possible to improve the life of the bladder by suppressing the aging and cracking of the bladder. It relates to a rubber band that can be.

The bladder is used to transfer heat into the tire during molding into the mold to cure the green tire as a preliminary step to produce the product tire, which must be discarded when aging or cracking occurs.

The types of bladder are classified into various types according to the tire vulcanizer. Currently, the bladder is divided into BOM type, AFV type, and MR type. Currently, bladder used for vulcanizer is mainly used MR type which is easy to install.

The type of bladder varies greatly in terms of aging and crack generation and lifespan. Especially in the case of MR type bladder, which is currently used the most, it is intensively aged at the bent ring. This aging shows the disadvantage of having to be discarded even though the other parts are intact, and thus there is a problem that the service life decreases relatively compared to other bladder.

In order to solve the above-mentioned problems, the present invention attaches a rubber band to the bent portion of the bladder in contact with the bead ring in the MR bladder to be inserted into the bead ring to prevent wear and impact by the contact of the bead ring Furthermore, it aims at suppressing generation | occurrence | production of the aging and a crack which arise in a curved part.

1 is a state diagram showing an MR bladder marked with the aging site

Figure 2 is a state diagram of the MR bladder attached to the rubber band of the present invention

<Explanation of symbols for the main parts of the drawings>

1: bladder 2: bead ring

3: center post 4: rubber band

5: bladder bend

The present invention is a rubber band characterized in that it is attached to the bent portion of the concentrated aging of the bladder to suppress the aging and cracks of the bladder, the rubber band composition of the present invention is a raw material rubber with respect to 100 phr of natural rubber carbon black (FEF 10-30 phr, zinc oxide (ZnO) 3-5 phr, stearic acid 2-4 phr, sulfur (S) 2-5 phr, Nt-butylbenzothiazole-Z-sulfenamide as a vulcanization accelerator (Nt-butylbenzothiazole -Z-sulfenamide, NS) 1 to 3 phr.

The physical properties of the rubber band by the rubber composition is 40 to 50 hardness, tensile strength 180 to 230, elongation (%) 400 to 600, 300% modulus 110 to 130.

Hereinafter, the role of the rubber band of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a state diagram illustrating an MR bladder in which a bladder 1 is inserted into a bead ring 2 connected to a center post 3, and the bladder interpolated into the bead ring 2. The curved part 5 of (1) is a part which is in direct contact with the bead ring 2, and intensive aging and cracks are generated by abrasion and impact by contact with the bead ring.

As described above, there is a problem in that other parts of the bladder 1 should be destroyed without abnormality due to aging and cracks occurring at the curved portion of the bladder bent between the bladder 1 and the bead ring 2. In order to solve this problem, as shown in FIG. 2, the rubber band 4 of the present invention is attached to the curved portion 5 of the bladder to suppress the wear and impact caused by the contact of the bead ring 2 to prevent the aging of the bladder and the growth of the crack. By reducing the life of the bladder.

Meanwhile, the rubber band width of the present invention is preferably maintained at 8 to 15 cm. If the width of the band is less than 8cm, the band has a short protection range from the bead ring in adhering to the bladder bent portion, and if the band exceeds 15cm, the rubber band is not good because it interferes with the bladder's role of heat transfer into the tire.

Hereinafter, the present invention will be illustrated by the following Comparative Examples and Examples. However, these do not limit the technical scope of the present invention.

<Comparative Example>

When the MR type bladder is used by a known method, the aging, crack growth, and average life of the bladder are measured five times, and the average results are shown in Table 1 below.

<Example>

10 to 30 phr of carbon black (FEF), 3 to 5 phr of zinc oxide (ZnO), 2 to 4 phr of stearic acid, 2 to 5 phr of sulfur (S), Nt-butylbenzothiane as a vulcanization accelerator Physical properties 40 ~ 50, tensile strength 180 ~ 230, elongation (%) 400 ~ 600, 300% modulus 110 ~, using 1 ~ 3 phr of Nt-butylbenzothiazole-Z-sulfenamide (NS) A rubber band of 130 is attached to the bladder curved portion of the bladder 1 and the bead ring 2, and then the aging, crack growth, and average life of the bladder are measured five times. Table 1 shows.

Table 1. Bladder Measurement Results of Comparative Examples and Examples

Item Comparative example Example Aging and Crack Growth Cracks occur around 230-250 times, and cracks grow from 270 times Cracks occur around 250 to 270 times, and cracks grow from 310 times Life expectancy 280 320 times

As shown in Table 1, by attaching the rubber band of the present invention to the bladder curved portion, it is possible to suppress the aging and crack growth of the bladder curved portion due to the contact of the bead ring, thereby improving the life of the bladder and frequently the bladder. The productivity can be improved by preventing replacement.

Claims (3)

Rubber band, characterized in that attached to the bent portion 5 of the bladder (1) in contact with the bead ring (2) to suppress aging and cracking of the bladder The rubber band according to claim 1, wherein the rubber band is a raw material rubber, 10-30 phr of carbon black (FEF), 3-5 phr of zinc oxide (ZnO), 2-4 phr of stearic acid, sulfur (S) 2 with respect to 100 phr of natural rubber. -5 phr, rubber band characterized by containing 1 to 3 phr of Nt-butylbenzothiazole-Z-sulfenamide (NS) as a vulcanization accelerator The rubber band according to claim 1, wherein the physical properties of the rubber band are 40 to 50 hardness, tensile strength 180 to 230, elongation (%) 400 to 600, and 300% modulus 110 to 130.