JPH03288631A - Manufacture of cushion tire for industrial vehicle - Google Patents

Abstract

PURPOSE:To recycle waste tires, and shorten the vulcanization time and thus improve the productivity thereof by utilizing, as a nucleus, a tire that is buffed at least in its tread and rim contact surface of the waste tire in which the tire outer periphery is abraded, and adhering a rubber material to the buffed part thereof, and vulcanizing them thereafter. CONSTITUTION:A part of the waste tire 22 is buffed in a predetermined range and, around the outer periphery of a tread part 16 A in the tread rubber layer 16 of the buffed tire 24, a sheet-shaped raw rubber sheet 26 is wound and then, on the outside of the tire side part 16 B of the tread tire layer 16, a sheet- shaped raw rubber sheet 28 is adhered. Furthermore, on the outside of a tire side part 14 C in a base rubber layer 14, a sheet-shaped rigid raw rubber sheet 32 blended with staple fibers 12 is adhered, thereby forming an unvulcanized tire 34. The unvulcanized tire 34 is set on a mold, and the mold is heated so as to vulcanize the unvulcanized tire 34.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a cushion tire for industrial vehicles.

[Conventional technology]

BACKGROUND OF THE INVENTION Conventionally, cushion tires for industrial vehicles, which are used for running on roads where rocks, ores, nails, etc. are scattered, such as at stone crushing sites, construction sites, or wasteland, bear a large load and are easily damaged. For this reason, it is required to have strong properties such as cut resistance and abrasion resistance, as well as strong insertion into the rim.

Therefore, we use tread rubber with excellent abrasion and cut resistance on the contact surface side of the tire, and on the inside, we use tread rubber to tighten the rim.
= In order to increase the I force, a base rubber with a high compressive elastic modulus has been used, and each rubber has shared the required characteristics.

Further, reinforcing rubber in which a predetermined amount of short fiber cords of organic fibers such as nylon and polyester are mixed is often used as the base rubber.

This base rubber is 40% to 6% of the cross-sectional height of the tire.
By using large amounts up to the 0% height range, the tire base has been strengthened and rim slip has been prevented.

In this cushion tire for industrial vehicles, unlike pneumatic tires for general vehicles, there is no legal regulation that requires replacement of the tire when the amount of wear on the tread reaches a predetermined value. Therefore, for waste tires with worn treads,
The amount of wear on the tread varies widely (and therefore the tire radius varies widely. Therefore, if a used tire is retreaded by wrapping a vulcanized tread rubber sheet of a predetermined thickness around the outer circumference of the tread rubber, the retreaded tire's There is a problem that the outer diameter varies.

In addition, in cushion tires for industrial vehicles, the tire side portions of the reinforcing layer and the rim abutting surfaces of the inner circumferential surface are worn out, and if these portions are not rehabilitated, this may cause rim displacement.

Therefore, in the case of cushion tires for industrial vehicles, worn out waste tires are not retreaded but are incinerated, resulting in waste.

[Problem to be solved by the invention]

In consideration of the above facts, the present invention has been developed to provide a cushion tire for industrial vehicles that is capable of reusing waste tires whose outer circumferential portions are worn or flattened, and which can shorten vulcanization time and improve productivity. The purpose is to obtain a manufacturing method for.

[Means to solve problems]

The present invention as set forth in claim (1) is directed to an industry that has a reinforcing rubber layer mixed with short fibers constituting the radially inner part of the tire and a trend rubber layer constituting the radially outer part of the reinforcing rubber layer. A method for manufacturing a cushion tire for a car, wherein a tire is made by buffing at least the ground contact surface and the rim contact surface of a waste tire whose outer circumferential portion is worn out, and a rubber material is pasted on the buffed portion of the core tire. It is characterized by being vulcanized.

Furthermore, the present invention as described in claim (2) includes a reinforcing rubber layer mixed with short fibers constituting the radially inner part of the tire and a trend rubber layer constituting the radially outer part of the reinforcing rubber layer. A method for manufacturing an industrial military cushion tire having the following steps: a core portion of the industrial vehicle cushion tire is molded and vulcanized in advance, a rubber material is adhered to at least a portion of the core portion, and the core portion is vulcanized. It is said that

[Effect]

In the present invention configured as described in claim (1),
Using a waste tire whose outer peripheral part has been worn out and buffing at least the ground contact surface and the rim abutting surface, a rubber material is adhered to the buffed portion of the core tire and vulcanized. Therefore, worn out tires can be reused, and
Since there are few vulcanized parts, vulcanization time can be shortened and productivity can be improved.

Furthermore, since not only the contact surface of the waste tire but also the rim contact surface is regenerated, rim displacement can be prevented.

In addition, in the present invention having the configuration described in claim (2), instead of a waste tire, the core part of a cushion tire for an industrial vehicle is vulcanized in advance, and at least a part of this core part is coated with a rubber material. Paste and vulcanize. Therefore, compared to the conventional case where the entire tire is vulcanized at once, the vulcanization time is shortened and productivity can be improved.

〔Example〕

A first embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

Generally, cushion tires for industrial vehicles have the following configuration.

As shown in FIG. 4, a cushion tire 10 for industrial vehicles
The radial cross-sectional structure of the tire is a structure in which the air filling part of a general pneumatic tire is filled with a rubber material. That is, the inner side in the radial direction of the tire (the right side in FIG. 4) is composed of a base rubber layer 14 as a short fiber layer, and this base rubber layer 14 has a structure in which short fibers 12 are mixed into hard rubber 13. It has become. Further, the outer side of the base rubber layer 14 in the tire radial direction (the left side in FIG. 4) is constituted by a tread rubber layer 16.

In addition, when assembling the industrial vehicle cushion tire 10 to the rim 20, force is applied to the industrial vehicle cushion tire 10 in the direction of the arrow in FIG. 4 (to the left in FIG. 4). The inner circumference of the cushion tire 10 is widened, and the arrow M in FIG.
Force is applied in the direction of arrow N (downward and upward in FIG. 4) to compress the tire width. Therefore, in the industrial vehicle cushion tire 10, the tread portion 16A, which is the contact surface of the tread rubber layer 16, wears out, and the contact surface of the base rubber layer 14 with the rim 20 becomes flat.

As shown in FIG. 1, in the manufacturing method of the industrial vehicle cushion tire of this embodiment, the tread portion 16A and tire side portion 16B of the tread rubber layer 16 come into contact with the rim 20 of the base rubber layer 14. When the surface 14A is flattened, at least a portion of the waste tire 22 is buffed within a predetermined range, and the first
A buffed tire 24 shown by imaginary lines in the figure is made.

Note that if the buffing area of the waste tire 22 is too large, the buffing work time, molding work time, and vulcanization time will become longer; however, for the above-mentioned reasons, at least the ground contact surface and the rim contact surface are buffed. It is.

Next, as shown in FIG. 2, a raw rubber sheet 26 is wrapped around the outer periphery of the tread portion 16A of the tread rubber layer 16 of the buffed tire 24, and the thickness of the tread rubber layer 16 in the tire radial direction is determined. The thickness is set to a predetermined value. Further, a sheet-shaped raw rubber sheet 28 is attached to the outside of the tire side portion 16B of the tread rubber layer 16, and the tire width dimension of the tread rubber layer 16 is set to a predetermined length.

Furthermore, a hard raw rubber sheet 30 mixed with short fibers 12 is wrapped around the inner peripheral surface 14B of the base rubber layer 14 of the buffed tire 24, and the thickness of the base rubber layer 14 in the tire radial direction is adjusted to a predetermined thickness. Thickness. Also, base rubber layer 1
A hard raw rubber sheet 32 mixed with sheet-like short fibers 12 is adhered to the outside of the tire side portion 14C of No. 4, and the tire width dimension of the base rubber layer 14 is set to a predetermined length, thereby producing an unvulcanized tire 34. .

Next, as shown in FIG. 3, the unvulcanized tire 34 is set in a mold 36. This mold 36 includes an upper mold 40 corresponding to the upper part of the equatorial plane 38 of the industrial vehicle cushion tire 10 shown in FIG. 4, and a lower mold 42 corresponding to the lower part in FIG.

Further, the mold 36 is configured such that the upper mold 40 opens toward the road in FIG. 3 (in the direction of arrow A in FIG. 3) with respect to the lower mold 42 at the split position 36A.

Therefore, the upper mold 40 is opened with respect to the lower mold 42 in the direction of the road in FIG. 1, and the upper mold 40 and the lower mold 42 are brought into contact (the state shown in FIG. 3).
shall be.

In this state, the mold 36 is heated to vulcanize the unvulcanized tire 34.

In this example, in order to manufacture the cushion tire 10 for an industrial vehicle by the above manufacturing method, the tread portion 16A and tire side portion 16B of the tread rubber layer 16 are brought into contact with the rim 20 of the base rubber layer 14. It is possible to reuse the waste tire 22 whose surface 14Δ is worn or flattened, and since there are fewer vulcanized parts compared to the conventional method of vulcanizing the entire tire, the vulcanization time can be shortened and productivity can be improved. be able to.

Furthermore, in this embodiment, since the entire circumference of the waste tire 22 is rehabilitated, the contact surface 14A of the base rubber layer 14 with the rim 20 is also rehabilitated. Therefore, the rim tightening force can be restored to the same level as that of a new tire, and rim displacement can be prevented.

In this embodiment, a tire obtained by buffing the entire circumference of the waste tire 22 was used as the core of the tire. Using this core portion 10A as a core, a raw rubber sheet is wrapped around the outer periphery of the tread portion 16A of the tread rubber layer 16 of the core portion 10A, and the tread rubber layer 16 is vulcanized in the tire radial direction. Let the thickness be a predetermined thickness 0. Also, the tire side portion 16 of the tread rubber layer 16
A sheet-like raw rubber sheet is attached to the outside of B, and the tire width dimension of the tread rubber layer 16 is set to a predetermined length. Further, a hard raw rubber sheet mixed with short fibers 12 is wrapped around the inner circumferential surface 14B of the base rubber layer 14, so that the thickness of the base rubber layer 14 in the tire radial direction is set to a predetermined thickness. Further, a hard raw rubber sheet mixed with sheet-like short fibers 12 is pasted on the outside of the tire side 14C of the base rubber layer 14, and the tire width dimension of the base rubber layer 14 is set to a predetermined length, and the unvulcanized tire is You can make it.

In this way, even when the core portion 10A of the industrial vehicle cushion tire 10 is vulcanized in advance and the core portion 10A is used instead of the waste tire 22, it is different from the conventional case where the entire tire is vulcanized at once. In comparison, the vulcanization time is shorter and productivity can be improved.

〔Effect of the invention〕

Since the present invention employs the above-described method, it is possible to reuse waste tires whose outer circumferential portions have worn out or become flat, and
It has the excellent effect of shortening vulcanization time and improving productivity.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the left half of a waste tire used in a method for manufacturing a cushion tire for an industrial vehicle according to an embodiment of the present invention, and FIG. 2 is a sectional view of a cushion tire for an industrial vehicle according to an embodiment of the present invention. FIG. 3 is a cross-sectional view showing the left half of an unvulcanized tire used in the tire manufacturing method; FIG. 4 is a sectional view showing the left half of a cushion tire for an industrial vehicle. 10 ・ 12 ・ 13 ・ 14 ・ 16 ・ 22 ・ 24 ・ 26, Cushion tire for industrial vehicles, short fiber, hard rubber, base rubber layer, tread rubber layer, waste tire, buff tire, ... raw rubber sheet, 1 2 30.32... Hard raw rubber sheet, 36... Mold, 40... Upper mold, 42... Lower mold.

Claims (2)

[Claims] (1) A method for producing a cushion tire for an industrial vehicle, comprising a reinforcing rubber layer mixed with short fibers constituting a radially inner part of the tire, and a treaded rubber layer constituting an outer part of the reinforcing rubber layer in a radial direction of the tire, comprising: An industrial vehicle characterized in that a tire is a core tire made by buffing at least the ground contact surface and the rim contact surface of a scrap tire whose outer circumferential portion is worn, and a rubber material is affixed to the buffed portion of the core tire and vulcanized. manufacturing method for cushion tires. (2) A method for manufacturing a cushion tire for an industrial vehicle, comprising a reinforcing rubber layer mixed with short fibers constituting the inner radial part of the tire, and a treaded rubber layer constituting the outer radial part of the reinforcing rubber layer, comprising: A method for producing a cushion tire for an industrial vehicle, comprising: molding and vulcanizing the core of the cushion tire for an industrial vehicle in advance, and adhering a rubber material to at least a portion of the core and vulcanizing the core.