JPH11165320A - Tire vulcanizing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To partly alter a rigidity of a rubber of a pneumatic tire. SOLUTION: A pipeline 42 is embedded near a width direction outside of a tread forming surface in an upside mold 18 and a lower side mold 20. Cooling water is circulated in the pipeline 42. The molds 18, 20 are heated to a predetermined temperature by an upper side platen and a lower side platen, and the water is circulated to the pipeline 42 to lower a temperature near the outside of the tread forming surface from that at the other part. Thus, the degree of vulcanization of the outside of the tread of the tire can be lowered from tat of the other part of the tread. A rubber hardness of the outside of the tread after the vulcanization can be lowered from that of the other part of the tread in spite of the same rubber material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tire vulcanizing apparatus for vulcanizing a tire.

[0002]

2. Description of the Related Art A tire vulcanizer has a built-in heater,
A green tire is loaded into a mold that forms an annular space inside, and a bladder expanded by a high-temperature gas or steam is pressed against the inner surface of the green tire, heated from inside and outside, and vulcanized.

In a conventional tire vulcanizing apparatus, a heater incorporated in a mold is provided so that the degree of vulcanization of rubber is constant.

[0004]

As a method of suppressing uneven wear of a pneumatic tire, for example, heel-and-toe wear generated on a block, the rigidity of a kick-out end is made higher than that of a stepped end of the block. Thus, it is conceivable to suppress wear on the kicking end side.

In addition, the rigidity on both sides in the tread width direction is low,
It is conceivable to improve the cornering characteristics by increasing the rigidity at the center in the width direction.

As a method of imparting rigidity to each predetermined region of the tread, it is conceivable to dispose different types of rubber in each predetermined region. However, in practice, the rubber flows in the mold and a desired position is obtained. May not be arranged.

[0007] It is also difficult to form a tread of a green tire by arranging different types of rubber in predetermined regions.

Further, when different types of rubber are used,
After vulcanization, separation may occur at the rubber boundary.

The present invention has been made in consideration of the above-described circumstances, and has as its object to provide a tire vulcanizing apparatus that can partially change the rigidity even when a single type of rubber is used.

[0010]

According to a first aspect of the present invention, there is provided a tire vulcanizing apparatus comprising: an annular space in which a raw tire made of unvulcanized rubber is loaded; It is characterized by comprising heating means for vulcanizing to a degree of vulcanization and changing means for changing the degree of vulcanization of a part of the green tire loaded in the annular space.

In the tire vulcanizing apparatus according to the first aspect, a green tire is loaded in the annular space, and the entire raw tire loaded in the annular space is heated by the heating means, and the whole is vulcanized to a predetermined degree of vulcanization. Sulfurized. Also, in this tire vulcanizer,
It is possible to change the degree of vulcanization of a part of the rubber of the raw tire by changing means, and by changing the degree of vulcanization of a part of the rubber, it is possible to partially change the hardness of the tire after vulcanization. it can.

For example, increasing the degree of vulcanization of rubber increases hardness, and decreasing the degree of vulcanization decreases hardness.

[0013] According to a second aspect of the present invention, in the tire vulcanizing apparatus according to the first aspect, the changing means is located near a tire kicking end or a stepping end of a block forming recess provided on a tread forming surface. It is characterized by being provided in.

In the tire vulcanizing apparatus according to the second aspect, since the changing means is provided near the tire kicking end or the stepping end of the block forming recess provided on the tread forming surface, the rubber block tire is provided. A difference can be made between the rigidity near the kicking end and the rigidity near the stepping end.

According to a third aspect of the present invention, in the tire vulcanizing apparatus according to the first aspect, the changing means is provided at a central portion of the tread forming surface in the tire width direction or at both side portions in the tire width direction. It is characterized by.

In the tire vulcanizing device according to the third aspect, since the changing means is provided at the central portion of the tread forming surface in the tire width direction or at both side portions in the tire width direction, the rigidity of the tread at the central portion in the tire width direction is improved. A difference can be made between the rigidity of both sides in the tire width direction.

According to a fourth aspect of the present invention, in the tire vulcanizing apparatus according to any one of the first to third aspects,
The changing means is a heater for heating the raw tire to a higher temperature than the heating means.

In the tire vulcanizing apparatus according to the fourth aspect, the vulcanization can be promoted by setting a part of the raw tire at a higher temperature than the other parts by the heater, thereby increasing the rubber hardness of the part. Can be higher than the part.

According to a fifth aspect of the present invention, in the tire vulcanizing apparatus according to any one of the first to third aspects,
The change means is a cooling means.

In the tire vulcanizing apparatus according to the fifth aspect, the vulcanization can be delayed by setting a part of the raw tire at a lower temperature than the other part by the cooling means. Part can be lower.

According to a sixth aspect of the present invention, in the tire vulcanizing apparatus according to any one of the first to fifth aspects,
The temperature of the rubber changed by the changing means is not less than 20 °.

In the tire vulcanizing apparatus according to the sixth aspect, since the temperature of the rubber changed by the changing means is 20 ° C. or more, for example, when a rubber member used for a tread of a general tire for a passenger car is used. By vulcanizing at 165 ° C. as compared with the case of vulcanizing at 145 ° C., the rubber hardness can be increased by about 3 degrees.

According to a seventh aspect of the present invention, in the tire vulcanizing apparatus according to any one of the first to fifth aspects,
The temperature of the rubber changed by the changing means is not less than 50 °.

In the tire vulcanizing apparatus according to the seventh aspect, the temperature of the rubber changed by the changing means is 50 ° C. or more, so that, for example, when a rubber member used for a tread of a general tire for a passenger car is used. By vulcanizing at 195 ° C. as compared with the case of vulcanizing at 145 ° C., the rubber hardness can be increased by about 5 degrees.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of a tire vulcanizing apparatus according to the present invention will be described with reference to FIGS.

As shown in FIG. 1, the tire vulcanizing device 10
Includes a mold unit 12 and a bladder unit 16 having an inflatable / reducible bladder 14.

The mold unit 12 includes an upper mold 18 and a lower mold 20 made of metal, and a raw tire 46 is loaded between the upper mold 18 and the lower mold 20.

The outer periphery of the mold unit 12 is covered by a jacket 22 as heating means. A passage 24 is provided in the jacket 22, and a heating fluid (steam, gas, hot water, or the like) flows through a pipe 26.

The side of the mold unit 12 corresponding to the tire peripheral surface is heated by the jacket 22.

In order to heat the end face side of the mold unit 12, an upper platen 25 and a lower platen 27 as heating means are disposed on the upper and lower sides thereof.

A passage 25A is formed in the upper platen 25, and a passage 27A is formed in the lower platen 27, and the heating fluid flows through a pipe (not shown).

The bladder 14 is attached to an upper ring 28 and a lower ring 30, and the upper ring 28 is fixed to a center post 32. This center post 32
The movement is indicated by a sleeve 34. For this reason, the bladder 14 can move according to the vertical movement of the center post 32.

The lower ring 30 is connected to pipes 36 and 38 for circulating a heating fluid through the bladder 14. Thereby, the bladder 14 is heated.

As shown in FIG. 2, a conduit 42 is embedded in the upper mold 18 and the lower mold 20 in the vicinity of the widthwise outer portion of the tread forming surface (inner peripheral surface). This conduit 42 extends in the circumferential direction.

The pipe 42 is connected to a cooling water generator (water cooler or the like) for generating cooling water via a pipe (both not shown), and the cooling water generated by the cooling water generator is connected to the pipe 42. It circulates on the road 42.

Next, the operation of the tire vulcanizing apparatus 10 of the present embodiment will be described. First, a green tire 46 is loaded between the upper mold 18 and the lower mold 20 and the upper mold 1
8 and the lower mold 20 are closed.

Next, a heating fluid such as steam is supplied to the bladder 14 to expand the bladder 14, and the raw tire 46 is pressed against the inner surface of the mold unit 12.

The jacket 22, the upper platen 25
The heating fluid is also supplied to the lower platen 27 to heat the entire mold unit 12 to a predetermined temperature.

In this way, the raw tire 46 can be heated from inside and outside, and the whole can be uniformly vulcanized.

Here, the tire vulcanizing apparatus 10 of the present embodiment
In this case, by circulating the cooling water through the pipe 42, the temperature in the vicinity of the widthwise outer portion of the tread forming surface (the inner peripheral surface) of the upper mold 18 and the lower mold 20 can be lowered as compared with other portions.

Thus, the degree of vulcanization of the outer portion in the width direction of the tread portion of the tire can be made lower than that of other portions of the tread portion, and the vulcanized tread portion is the same rubber member. Of the tread portion can be made lower than the rubber hardness of the other portion in the width direction.

At the time of cornering, the load on the outer portion of the tread portion in the tire width direction is increased. If the rubber hardness of the portion is low, the contact with the road surface is improved, and the cornering performance is improved.

That is, by vulcanizing the raw tire 46 using the tire vulcanizing apparatus 10 of the present embodiment, a pneumatic tire having excellent cornering performance can be formed.

In the present embodiment, cooling water is circulated through the conduit 42 in order to partially lower the degree of vulcanization of the raw tire 46, that is, to partially lower the rubber hardness of the vulcanized tire. However, in order to partially increase the degree of vulcanization of the raw tire 46, that is, to partially increase the rubber hardness of the vulcanized tire, the heating fluid (jacket 22, upper platen 25
And higher temperature than the heating fluid supplied to the lower platen 27)
May be circulated.

By doing so, the degree of vulcanization of the outer portion in the width direction of the tread portion can be made higher than that of the other portions of the tread portion. The rubber hardness of the outer portion in the width direction can be higher than the rubber hardness of other portions of the tread portion.

In the pneumatic tire, when the rubber hardness of the outer portion in the width direction of the tread portion is increased, the wear of the shoulder portion (so-called abrasion against shoulder drop) can be suppressed.

The conduit 42 may be buried in the vicinity of the widthwise inner part of the tread forming surface of the upper mold 18 and the lower mold 20. In this case, by circulating the cooling water through the conduit 42, the degree of vulcanization of the inner portion in the width direction of the tread portion can be made lower than that of the other portion of the tread portion, and although the same rubber member is used. In addition, the rubber hardness of the inside of the tread portion in the width direction after vulcanization can be made lower than the rubber hardness of other portions of the tread portion.

The heating fluid supplied to the jacket 22, the upper platen 25 and the lower platen 27 in the conduit 42 buried near the widthwise inner portion of the tread forming surface of the upper mold 18 and the lower mold 20 is smaller than that of the heating fluid. A high-temperature heating fluid may be circulated. In this case, the degree of vulcanization of the inner portion in the width direction of the tread portion can be made higher than that of the other portions of the tread portion. The rubber hardness of the widthwise inside portion of the tread portion after vulcanization can be higher than the rubber hardness of the other portion of the tread portion. [Second Embodiment] A tire vulcanizing apparatus according to a second embodiment of the present invention will be described with reference to FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The mold unit 12 of the present embodiment includes:
A plurality of block forming recesses 48 for forming a block pattern are formed, and the conduit 42 is buried in the vicinity of the kick-out side of the block.

By circulating a heating fluid having a higher temperature than the heating fluid supplied to the jacket 22, the upper platen 25 and the lower platen 27 through the conduit 42, the rigidity at the ejection end side is higher than that of the other portions. Can be molded.

By increasing the rubber hardness on the kick-out end side of the block, wear on the kick-out end side can be suppressed more than on the step-in end side, and heel-and-toe wear can be suppressed. .

The pipe 42 may be embedded near the stepping end of the block to be formed. In this case, by circulating the cooling water through the conduit 42, the rigidity at the stepping end side can be reduced as compared with other portions. In this case, it is possible to reduce the impact sound when the block steps on the road surface.

In the first and second embodiments, a high-temperature heating fluid is supplied to the pipe 42 to increase the degree of vulcanization of a part of the rubber. And may be irradiated with a microwave for generating heat in the rubber.

The part of the rubber whose hardness is changed is not limited to the tread part, but may be a side part, a bead part, or the like. The position where the pipe 42 is embedded is the part described in the above embodiment. Not exclusively.

By the way, when a rubber member used for a tread of a general passenger car tire is used, vulcanization at 145 ° C. is carried out at 165 ° C. to increase the rubber hardness by about 3 degrees. By vulcanizing at 195 ° C., the rubber hardness can be increased by about 5 degrees.

[0056]

As described above, the tire vulcanizing apparatus according to the first aspect has the above-described configuration, and therefore, the hardness of the vulcanized tire is partially reduced without using different types of rubber members. It has an excellent effect that it can be changed.

Since the tire vulcanizing device according to the second aspect has the above-described configuration, an excellent effect that the rigidity near the kick-out end of the rubber block and the rigidity near the step-in end can be differentiated. Having.

Since the tire vulcanizing device according to the third aspect has the above-described configuration, the rigidity of the central portion of the tread in the tire width direction and the rigidity of both sides in the tire width direction can be differentiated. Has an effect.

Since the tire vulcanizing apparatus according to the fourth aspect has the above-described structure, it has an excellent effect that the rubber hardness of a part of the tire can be made higher than that of the other parts.

The tire vulcanizing apparatus according to the fifth aspect has the above-described configuration, and thus has an excellent effect that the rubber hardness of a part of the tire can be made lower than that of the other parts.

The tire vulcanizing device according to the sixth aspect has the above-described configuration, and thus has an excellent effect that the rubber hardness of a part of the tire can be increased by about three degrees as compared with other parts.

The tire vulcanizing apparatus according to the seventh aspect has the above-described configuration, and thus has an excellent effect that the rubber hardness of a part of the tire can be made about 5 degrees higher than the other parts.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a tire vulcanizing apparatus according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a mold unit.

FIG. 3 is a sectional view of a main part of a tire vulcanizing apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Tire vulcanizing apparatus 22 Jacket (heating means) 25 Upper platen (heating means) 27 Lower platen (heating means) 42 Pipe line (changing means, cooling means)

Claims (7)

[Claims] 1. An annular space for loading a green tire made of unvulcanized rubber, heating means for vulcanizing the entire green tire loaded in the annular space to a predetermined degree of vulcanization, Changing means for changing a degree of vulcanization of a part of the loaded raw tire; and a tire vulcanizing apparatus comprising: 2. The tire vulcanizing device according to claim 1, wherein said changing means is provided near a kick-out end or a step-in end of a block forming recess provided on a tread forming surface. apparatus. 3. The tire vulcanizing apparatus according to claim 1, wherein the changing means is provided at a central portion of the tread forming surface in the tire width direction or at both side portions in the tire width direction. 4. The tire vulcanizing apparatus according to claim 1, wherein the changing unit is a heater that heats the green tire to a higher temperature than the heating unit. . 5. The tire vulcanizing apparatus according to claim 1, wherein the changing unit is a cooling unit. 6. The tire vulcanizing apparatus according to claim 1, wherein the temperature of the rubber changed by the changing means is 20 ° C. or more. 7. The tire vulcanizing apparatus according to claim 1, wherein the temperature of the rubber changed by the changing means is 50 ° C. or more.