JP2927875B2 - Manufacturing method of cushion tires for industrial vehicles - Google Patents

Description

The present invention relates to a method for manufacturing a cushion tire for an industrial vehicle.

[Conventional technology]

2. Description of the Related Art Conventionally, cushion tires for industrial vehicles used for traveling on a road surface where rocks, ores, nails and the like are scattered, such as a crushed stone site, a construction site, or a wasteland, have a large load and are easily damaged. For this reason, it is required that insertion into the rim be strong, in addition to various properties such as cut resistance and wear resistance.

Therefore, tread rubber with excellent abrasion resistance and cut resistance is used on the contact surface side of the tire, and a rim and base rubber with high compression modulus are used inside the tire to increase the tightening force. The required characteristics. Further, as the base rubber, a reinforcing rubber in which a predetermined amount of a short fiber cord of an organic fiber such as nylon or polyester is mixed is frequently used. And this base rubber has a tire cross section height of 40
By using a large amount in the range of% to 60% height,
The tire base has been strengthened to prevent rim slip.

In the cushion tire for an industrial vehicle, there is no legal restriction that the tire must be replaced when the worn amount of the tread portion reaches a predetermined value like a pneumatic tire for a general vehicle. Therefore, in a waste tire having a worn tread portion, the amount of wear in the tread portion varies greatly, so that the tire radius varies greatly. Therefore, when a waste tire is rehabilitated by winding a vulcanized tread rubber sheet having a predetermined thickness around the outer circumference of the tread rubber, there is a problem that the outer diameter of the rehabilitated tire varies.

In addition, in a cushion tire for an industrial vehicle, the rim contact surface of the tire side portion of the reinforcing layer and the inner peripheral surface is depressed, and if this portion is not rehabilitated, the rim may be displaced.

Accordingly, in a cushion tire for an industrial vehicle, worn waste tires are incinerated without being rehabilitated and are wasted.

[Problems to be solved by the invention]

In consideration of the above fact, the present invention can reuse a waste tire whose outer peripheral portion has been worn or sagged, and can shorten the vulcanization time and improve the productivity, thereby improving the productivity. It is intended to obtain a manufacturing method of the.

[Means to solve the problem]

The present invention described in claim (1) is an industrial vehicle having a reinforcing rubber layer mixed with short fibers constituting a radially inner portion of a tire and a tret rubber layer constituting a tire radially outer portion of the reinforcing rubber layer. A method of manufacturing a cushion tire for use in a tire, wherein a tire having a buffed at least a ground contact surface and a rim contact surface of a waste tire having a worn outer peripheral portion is a nucleus, and a sheet-like rubber material is attached to a buff portion of the core tire. And vulcanized.

According to a second aspect of the present invention, there is provided the method for manufacturing a cushion tire for an industrial vehicle according to the first aspect, wherein the rubber material to be attached and the buff portion to which the rubber material is attached are attached. It is characterized by being made of the same material.

The present invention described in claim (3) has a reinforcing rubber layer mixed with short fibers constituting the radially inner portion of the tire and a tread rubber layer constituting the tire radially outer portion of the reinforcing rubber layer. A method for manufacturing a cushion tire for an industrial vehicle, comprising: forming and vulcanizing a core of the cushion tire for an industrial vehicle in advance; and forming a core of the same material as a core attached to at least a part of the core. A vulcanized sheet-like rubber material is stuck and vulcanized.

[Action]

In the present invention having the configuration described in the claim (1), a buffed portion of the tire serving as a nucleus is formed by buffing at least a tread surface and a rim contact surface of a waste tire having a worn outer peripheral portion. And vulcanize it. Therefore, the worn tire can be reused, and since the vulcanized portion is small, the vulcanization time can be shortened and the productivity can be improved.

Further, since not only the ground contact surface of the waste tire but also the rim contact surface is rehabilitated, rim displacement can be prevented.

In the present invention having the configuration described in claim (2), at least a tire having a buffed at least a ground contact surface and a rim contact surface of a waste tire having a worn outer peripheral portion is used as a core to buff the tire. Then, a sheet-like rubber material made of the same material as the buff portion to be attached is attached and vulcanized. Therefore, the worn tire can be reused, and since the vulcanized portion is small, the vulcanization time can be shortened and the productivity can be improved.

In addition, since not only the ground contact surface of the waste tire but also the rim contact surface is rehabilitated, rim displacement can be prevented.

In the present invention having the structure described in claim (3), the core of the cushion tire for industrial vehicles is vulcanized in advance instead of the waste tire, and the core is affixed to at least a part of the core. An unvulcanized sheet rubber material made of the same material as that of the core is adhered to each other and vulcanized. For this reason, compared with the conventional case of vulcanizing the entire tire at one time, the vulcanization time is shortened and the productivity can be improved.

〔Example〕

Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

Generally, a cushion tire for an industrial vehicle is configured as follows.

As shown in FIG. 4, a cushion tire 10 for an industrial vehicle is provided.
Is a structure in which a rubber material is filled in an air filling portion of a general pneumatic tire. That is, the inner side in the tire radial direction (the right side in FIG. 4) is constituted by a base rubber layer 14 as a short fiber layer.
Reference numeral 14 denotes a configuration in which the short fibers 12 are mixed in the hard rubber 13. In addition, the outer side of the base rubber layer 14 in the tire radial direction (the fourth
The left side of the figure) is composed of a tread rubber layer 16.

When assembling the cushion tire 10 for industrial vehicles to the rim 20, a force is applied to the cushion tire 10 for industrial vehicles in the direction of arrow L in FIG. 4 (to the left in FIG. 4). The inner circumference of the vehicular cushion tire 10 is widened, and a force is applied in the directions indicated by arrows M and N in FIG. 4 (downward and upward in FIG. 4) to compress the tire width. For this reason, in the cushion tire 10 for an industrial vehicle, the tread portion 16A as the ground surface of the tread rubber layer 16 is worn, and the rim 2 of the base rubber layer 14 is worn.
The contact surface with 0 will be slack.

As shown in FIG. 1, in the method for manufacturing a cushion tire for an industrial vehicle according to the present embodiment, the tread portion 16A and the tire side portion 16B of the tread rubber layer 16 and the base rubber layer 14 are provided.
The buffed tire 24 shown by the imaginary line in FIG. 1 is produced by buffing at least a part of the waste tire 22 in a predetermined range, with the contact surface 14A with the rim 20 of the waste tire having been damaged.

In addition, if the buffing range of the waste tire 22 is too large, the buffing operation time, the molding operation time and the vulcanization time become longer, but at least the ground contact surface and the rim contact surface are buffed for the above-described reason. It is.

Next, as shown in FIG. 2, a sheet-like raw rubber sheet 26 is wound around 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 set to a predetermined value. Thickness. Also a tread rubber layer
A sheet-like raw rubber sheet 28 is adhered to the outside of the 16 tire side portions 16B, and the tire width dimension of the tread rubber layer 16 is set to a predetermined length.

Further, a hard raw rubber sheet 30 mixed with sheet-like short fibers 12 is wound 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 set to a predetermined value. Thickness. Further, a hard raw rubber sheet 32 mixed with sheet-like short fibers 12 is attached to the outside of the tire side portion 14C of the base rubber layer 14, the tire width dimension of the base rubber layer 14 is set to a predetermined length, and unvulcanized. Build tire 34.

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

In addition, the mold 36 has the upper mold 4 at the split position 36A.
0 corresponds to the lower mold 42 in a substantially upward direction in FIG.
It opens in the direction of arrow A in the figure).

Therefore, the upper mold 40 is moved relative to the lower mold 42.
1, the unvulcanized tire 34 is set in the lower mold 42 and the upper mold 40 is opened.
Is moved substantially downward in FIG. 1, and the upper mold 40 and the lower mold 42 are brought into contact with each other (the state shown in FIG. 3).

In this state, the mold 36 is heated, and the unvulcanized tire 34 is vulcanized.

In the present embodiment, in order to manufacture the cushion tire 10 for an industrial vehicle by the above manufacturing method, the contact surface between the tread portion 16A and the tire side portion 16B of the tread rubber layer 16 and the rim 20 of the base rubber layer 14 is used. 14A is worn or sparse,
The waste tire 22 can be reused, and the vulcanization time is shortened and productivity can be improved because the vulcanized portion is smaller than in the conventional method of vulcanizing the entire tire.

Further, in this embodiment, in order to rehabilitate the entire circumference of the waste tire 22, the contact surface 14A of the base rubber layer 14 with the rim 20 is also rehabilitated. Therefore, since the rim tightening force can be returned to the same level as that of a new tire, 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. Instead, the core 10A of the cushion tire 10 for industrial vehicles (the imaginary line in FIG. 4) was used instead. The core portion 10A is used as a core, and a sheet-like raw rubber sheet is wound around the outer periphery of the tread portion 16A of the tread rubber layer 16 of the core portion 10A.
The thickness in the tire radial direction is a predetermined thickness. Further, a sheet-like raw rubber sheet is adhered 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. Further, a hard raw rubber sheet in which sheet-like short fibers 12 are mixed is wound around the inner peripheral surface 14B of the base rubber layer 14, and 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 attached to the outside of the tire side 14C of the base rubber layer 14, the tire width dimension of the base rubber layer 14 is set to a predetermined length, and the unvulcanized tire is May be made.

As described above, the core of the industrial vehicle cushion tire 10 is previously determined.
When vulcanizing 10A and using this core first 10A in place of waste tire 22, the vulcanization time can be reduced and productivity can be improved compared to the conventional case where the entire tire is vulcanized at once. it can.

〔The invention's effect〕

Since the present invention employs the above-described method, it is possible to reuse a waste tire whose outer peripheral portion has been worn or sagged, and has an excellent effect of shortening the vulcanization time and improving productivity. Have.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a left half of a waste tire used in the method for manufacturing an industrial vehicle cushion tire according to one embodiment of the present invention, and FIG. 2 is an industrial vehicle cushion tire according to one embodiment of the present invention. FIG. 3 is a cross-sectional view showing an unvulcanized tire used in the method for manufacturing a tire in the left half thereof. FIG. 3 shows a mold used in the method for manufacturing a cushion tire for industrial vehicles according to one embodiment of the present invention in the left half thereof. FIG. 4 is a sectional view showing the cushion tire for an industrial vehicle in the left half thereof. 10… Cushion tire for industrial vehicles, 12… Short fiber, 13… Hard rubber, 14 …… Base rubber layer, 16 …… Tred rubber layer, 22 …… Waste tire, 24 …… Buff tire, 26, 28… … Green rubber sheet, 30, 32… Hard raw rubber sheet, 36 …… Mold, 40 …… Upper mold, 42 …… Lower mold.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B29D 30/00-30/72 B60C 7/00, 7/10, 7/22

Claims (3)

(57) [Claims] 1. A method for manufacturing a cushion tire for an industrial vehicle, comprising a reinforcing rubber layer mixed with short fibers constituting a radially inner portion of a tire and a tret rubber layer constituting a radially outer portion of the reinforcing rubber layer. At least a tire having a buffed at least a ground contact surface and a rim contact surface of a waste tire having a worn outer peripheral portion is a core, and a sheet-like rubber material is attached to a buff portion of the core tire and vulcanized. A method for producing a cushion tire for an industrial vehicle. 2. The method for producing a cushion tire for an industrial vehicle according to claim 1, wherein said rubber material to be attached and a buff portion to be attached are made of the same material. 3. A method for manufacturing a cushion tire for an industrial vehicle, comprising a reinforcing rubber layer mixed with short fibers constituting an inner portion in the tire radial direction and a tread rubber layer constituting an outer portion in the tire radial direction of the reinforcing rubber layer. The core of the industrial car cushion tire is molded and vulcanized in advance, and an unvulcanized sheet-like rubber material made of the same material as the core to be attached to at least a part of the core is attached. And producing a cushion tire for industrial vehicles.