JPS61239938A - Preparation of retreaded tire - Google Patents

Abstract

PURPOSE:To prepare a retreaded tire to which characters of a tire size, a pattern name or a trade mark not erased by abrasion of a treated and not becoming difficult to discriminate, by continuously forming unvulcanized side treads to both ends of an unvulcanized tread by molding and subsequently precuring the whole to prepare a precured tread and precured side treads before adhereing the same to the buffed surfaces of a tread part and side upper parts. CONSTITUTION:The tread part 2 and side upper parts 3 of a tire 1 to be retreaded are removed by buffing to prepare a base tire 5 having buffed surfaces 4. Subsequently, an unvulcanized tread and unvulcanized side treads having a width sufficient to continuously stamp characters to both sides of said tread are inserted in a mold and precured under pressure and heating to integrally prepare a precured tread 8 and precured side treads 9 each having a predeter mined length. A seal 10 such as a tire size is transferred to the surface9a of each side tread 9 from the mold. Next, the tread 8 and the side treads 9 are adhered to the buffed surfaces 4a, 4b of the base tire 5 and cured along with the base tire 5 by a retreaded tire vulcanizing apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for manufacturing a retreaded tire, for example, a method for manufacturing a retreaded tire using a vulcanized precure tread.

(Prior Art) As a conventional method for manufacturing a retreaded tire, for example, there is a method as described below, and this method will be explained using FIGS. 5 to 7.

FIG. 5 is a sectional view of a retreaded tire illustrating a conventional method for manufacturing a retreaded tire. First, in FIG. 5, 31 is a tire to be retreaded, and the tread portion (partially worn) 32 and the surface layer portion 33a (indicated by diagonal lines) of the upper side 33 of the tire 31 to be retreaded are removed by a grinder (indicated by diagonal lines). (not shown), a buffed surface 35 is created, and a so-called base tire 36 is manufactured.

Next, on the buff surface 35a of the tread portion of the base tire 36,
A pre-cured tread 37, which has been pre-cured and prepared in advance, as shown in FIGS. 6 and 7, is applied. On the side of the precure tread 37, there are generally characters 38 indicating the tire size, tire pattern name, trademark, etc.
is engraved.

(Problems to be Solved by the Invention) However, as shown in FIG. 6, in the precure tread 37, the area of the side surface 39 of the precure tread 37 is small due to the grooves 40 of the pattern, etc. There is a problem that only small characters of about 10 cranes can be engraved, making it difficult to identify the characters. Also, side 39
Even if characters are engraved on the tires, there is a problem that the engraved characters will disappear as retreaded tires are used and wear progresses. Furthermore, the buffed surface 35b of the upper portion 33 of the base tire 36 is usually left buffed or covered with a thin rubber sheet (not shown). Therefore, the appearance of the upper side portion 33 is very poor, and its commercial value is lower than the appearance of a retreaded tire manufactured by a so-called full mold retreaded tire manufacturing method in which the entire surface of the side portion 42 of the base tire 36 is retreaded. The problem is that it is low.

Therefore, the present invention provides a method for manufacturing a retreaded tire, in which characters such as tire size, pattern name, trademark, etc. can be engraved when manufacturing a retreaded tire, and the characters do not disappear due to tread wear and do not become difficult to identify. In addition, it is an object of the present invention to provide a method for manufacturing a retreaded tire that has a good appearance on the upper side of a stand tire and has a high commercial value comparable to the appearance of a fully molded retreaded tire.

(Means for Solving the Problems) The method for manufacturing a retreaded tire according to the present invention includes buffing and removing the tread portion and upper side of the tire to be retreaded to create a buffed surface, and applying precure to the buffed surface of the tread portion. In a method for producing a retreaded tire in which a precure tread is applied and vulcanized, before the vulcanization, unvulcanized side treads are continuously formed on both ends of the unvulcanized tread, and then precured and pre-cured. The method is characterized in that a cured tread and a precure side tread are manufactured, and then the precure tread and the precure side tread are applied to the buff surface of the tread portion and the upper side.

Here, "buffing" refers to scraping off the rubber surface using a cylindrical grinder with a serrated cutting edge on the surface, a so-called buffing machine, and the "buffing surface" refers to the scraped surface. In addition, "precure" refers to the process of vulcanizing unvulcanized rubber by pressurizing and heating it by a predetermined amount in advance, and "precure tread" refers to vulcanizing unvulcanized tread rubber by applying pressure and heating to a predetermined amount. This refers to a tread that is pre-vulcanized and molded.

(Operation) When manufacturing a retreaded tire, an unvulcanized side tread is formed continuously on both ends of an unvulcanized tread, and then precure is performed to manufacture an integrated precure tread and precure side tread. Ru. Therefore, characters can be engraved on the surface of the side tread having a sufficient area, and since the characters are provided on the side tread which will not wear out, they will not disappear due to wear or become difficult to identify.

Further, a precure tread and a precure side tread having the characters engraved on the precure side tread are attached to the buff surface of the tread portion and the upper side. Therefore, the appearance of the upper side of the base tire is good and the product value is high.

Hereinafter, one embodiment of the method for manufacturing a retreaded tire according to the present invention will be described based on the drawings.

(Example) FIGS. 1 to 4 are diagrams for explaining a method for manufacturing a retreaded tire according to the present invention, and FIG. 1 is a schematic cross-sectional view during manufacture of a retreaded tire.

First, the steps of the manufacturing method of the present invention will be explained. 1st
In the figure, the tread part 2 of the tire 1 to be retreaded (the tread part 2a is partially worn) and the upper side part 3 (
(both shown with dotted lines) are removed by buffing using a buffing machine, and a base tire 5 (shown with solid lines) having a buffed surface 4 is manufactured.

2, the unvulcanized side tread is then placed in a mold (not shown in the figure) having a width sufficient to stamp the unvulcanized tread and continuous text on both ends thereof before being vulcanized. The precure tread 8 and the pre-cured tread (not shown in the figure) are inserted into a pre-cured tread (not shown in the figure) and have a pre-cured length Lll (not shown) as shown in FIG. 2.

(not shown) Precure Site Do1
Red 9 is produced. On the surface 9a of the precure side tread 9, stamps 1O such as tire size, pattern name, trademark, etc. are transferred from the mold.

Here, the length of the precure side tread 9 is the length of the precure tread, which is shorter (although it is manufactured, it may be the same length.
The thickness t)+z of the rubber layer 12 between
), more preferably 0.1 to 1 m. Also, the thickness of Precure side tread 9 is 2 to 5 fl.
(31 in this example). Further, the width W of the precure side tread 9 is 10 to 50 m (30 m in this embodiment).

Next, the pre-cured tread 8 and the pre-cured side tread 9 manufactured as one unit are shown in FIGS. 3 and 4.
As shown in the figure, in the buffed surface 4 of the base tire 5, the buffed surface 4a of the tread portion 2 and the buffed surface 4b of the side upper part 3
At the same time, it can be attached efficiently and integrally.

Next, the base tire 5 to which the precure tread 8 and the precure side tread 9 are attached is vulcanized by a vulcanization device for retreaded tires.

In the retreaded tire 13 manufactured in this manner, the precure side tread 9 having a width W9 sufficient for stamping characters on both ends 8a of the precure tread 8 on the buff surface 4 of the base tire 5 is made of rubber. Because it is integrally formed by layer 12, the letters will not fade due to tread wear and will not become difficult to identify. In addition, since the precure side tread 9 is affixed to the buff surface 4b on the upper side of the side, a retreaded tire with good appearance and high commercial value can be manufactured. This greatly improves manufacturing efficiency,
This is a highly productive method for manufacturing retreaded tires.

In addition, in the above-mentioned embodiment, the case where the pre-cured side tread 9 and the pre-cured tread 8 are pre-cured and manufactured as one body was explained, but the present invention is not limited to this embodiment. 9 may be manufactured by pre-curing only the precure side tread 9 separately from the precure tread 8.

Furthermore, in the above-mentioned embodiment, the case where the precure side tread 9 is attached to the base tire 5 at the same time as the precure tread 8 was explained, but in the present invention, the precure side tread 9 is attached to the precure tread 8. You can attach it separately.

(Effects of the Invention) As explained above, according to the present invention, the tire size,
Characters such as pattern names and trademarks can be engraved, and they will not disappear due to tread wear and will not become difficult to identify. Furthermore, it is possible to provide a method for manufacturing a retreaded tire that has a good appearance on the upper side of the base tire and has a high commercial value comparable to the appearance of a fully molded retreaded tire.

Furthermore, since the pre-cured tread and the pre-cured side tread are pre-cured and manufactured as a single unit, the process of attaching them to the base tire is reduced, and the manufacturing efficiency of retreaded tires can be greatly improved, resulting in extremely high productivity. It is possible to provide a method for manufacturing a retreaded tire with significantly improved width.

[Brief explanation of the drawing]

Figures 1 to 4 are diagrams for explaining an embodiment of the method for producing a retreaded tire according to the present invention, in which Figure 1 is a schematic cross-sectional view of the tire to be retreaded, and Figure 2 is an enlarged cross-section of the main parts thereof. Figure, 3rd
The figure is a schematic sectional view of the retreaded tire, and Figure 4 is I of Figure 3.
It is a partial side view taken along the line V-IV. Figures 5 to 7 are diagrams for explaining a retreaded tire produced by a conventional method for manufacturing a retreaded tire, in which Figure 5 is a schematic sectional view thereof, Figure 6 is an enlarged side view of its main parts, and Figure 7 is a conventional method for manufacturing a retreaded tire. FIG. 3 is a cross-sectional view of the precure tread. 1... Tire to be retreaded, 2... Tread section, 3... Upper side, 4... Buffed surface, 8... Precure Tread, 9...Pre-cured side tread, ㅅ12...Rubber layer, 13...Retreaded tire. Figure 1 Figure 2

Claims (4)

[Claims] (1) Buff and remove the tread part and upper side of the tire to be retreaded to create a buffed surface, and apply the pre-cured tread to the buffed surface of the tread part.
In the method for manufacturing a retreaded tire that is cured, before the vulcanization, an unvulcanized side tread is formed continuously on both ends of the unvulcanized tread, and then precure is performed to form a precure tread and a precure side tread. 1. A method for manufacturing a retreaded tire, which comprises manufacturing a retreaded tire, and then applying a precure tread and a precure side tread to the buffed surface of the tread portion and the upper side. (2) The method for manufacturing a retreaded tire according to claim (1), wherein the precure side tread is manufactured by pre-curing the precure side tread integrally with the precure tread. (3) The method for manufacturing a retreaded tire according to claim (1), wherein the precure side tread is manufactured by pre-curing only the precure side tread separately from the precure tread. (4) Claim No. 1 characterized in that a rubber layer having a thickness of 0.1 to 1 mm is integrally formed between the precure tread and the precure side tread.
) The method for producing a retreaded tire as described in item 2.