JP2020104441A - Tire vulcanization system - Google Patents

Abstract

To provide a tire vulcanization system which has excellent accuracy in detecting bladder punctures.SOLUTION: The tire vulcanization system 2 is equipped with a mold 6 and a puncture detection device 22. The mold 6 has a plurality of segments 24, an upper side plate 26 and a lower side plate 28. In the closed position with the mold 6 closed, an outer surface 10a of the upper plate 10 and an inner surface 38a of the actuator 16 are opposed to each other. A flow channel 46 is formed that is recessed from the outer surface 38a or the inner surface 10a. The flow channel 46 is communicated with the puncture detection device 22.SELECTED DRAWING: Figure 1

Description

The present invention relates to a tire vulcanizing apparatus.

In a tire vulcanization process, a raw cover is put into a mold. The bladder, which is filled with steam and expanded, presses the raw cover against the cavity surface of the mold. A tire having a shape following the cavity is molded from the raw cover. Prolonged use can damage the bladder and allow steam to escape from the bladder. This steam leakage causes vulcanization failure of the tire. In order to suppress the occurrence of this vulcanization molding defect, the vulcanization device may include a puncture detection device for the bladder. An example of this puncture detection device is described in Japanese Unexamined Patent Publication No. 2010-11596.

JP, 2010-15796, A

In the tire vulcanization step, a mold including a plurality of segments arranged in the circumferential direction and formed into a ring shape, and a pair of side plates positioned radially inward at the axial end portions of the segments may be used. is there. In this mold, the segment forms the tread surface of the tire and the pair of side plates forms the axial outer surface. A vulcanizer including this mold includes a sector and an actuator that move the segment in the radial direction, and an upper plate that moves the side plate in the axial direction.

In this vulcanizing device, the puncture detecting device detects the vapor that reaches the sensor through the gap between the segment, the side plate, the actuator, the upper plate, and the like. The bladder puncture may not be detected because it is detected by the steam passing through this slight gap. On the other hand, if even a slight leak is made easy to detect, a puncture will be falsely detected.

An object of the present invention is to provide a tire vulcanizing device having excellent detection accuracy for puncture of a bladder.

The tire vulcanizing apparatus according to the present invention,
A plurality of segments that form the tread surface of the tire, and a mold that includes a pair of side plates that form the outer surface of the tire in the axial direction,
A sector to which the segment is attached,
An actuator that moves the sector and the segment in the radial direction by moving in the axial direction;
An upper plate that moves one side plate of the pair of side plates in the axial direction by moving in the axial direction;
A bladder that expands and contracts with a heating and pressurizing medium,
A puncture detection device for detecting a leak of the heating and pressurizing medium from the bladder.
In the closed posture in which the mold is closed, the outer peripheral surface of the upper plate and the inner peripheral surface of the actuator face each other. This vulcanizing device is provided with a flow channel recessed from the outer peripheral surface or the inner peripheral surface. The flow path communicates with the puncture detection device.

Preferably, the flow path is formed by a groove recessed from the inner peripheral surface of the actuator.

Preferably, the groove has a vertical width of 1 mm or more and a lateral width of 3 mm or more.

The tire vulcanizing device includes a ventilation hole that connects the flow passage and the puncture detecting device. The diameter of the ventilation hole is preferably 3 mm or more.

The tire vulcanizing device includes a ventilation hole that connects the flow passage and the puncture detecting device. Preferably, the actuator comprises an actuator body and an actuator ring mounted on the actuator body. The flow path and the ventilation hole are formed in the actuator ring.

The tire vulcanizing apparatus according to the present invention includes a flow channel that is recessed from the outer peripheral surface of the upper plate or the inner peripheral surface of the actuator. The pressurized heating medium easily flows into this flow path. This flow path communicates with the puncture detection device. The heating/pressurizing medium reaches the puncture detecting device through this flow path. This tire vulcanizing device is excellent in the accuracy of detecting the puncture of the bladder.

FIG. 1 is a sectional view showing a part of a tire vulcanizing apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view showing a part of the tire vulcanizing apparatus of FIG. 3(a) is a partially enlarged view of the tire vulcanizing apparatus of FIG. 1, and FIG. 3(b) is a partially enlarged view of the sector viewed in the direction of arrow b in FIG. 3(a). FIG. 4A is an explanatory diagram showing a usage state of the tire vulcanizing apparatus of FIG. 1, and FIG. 4B is an explanatory diagram showing another usage state of the tire vulcanizing apparatus.

Hereinafter, the present invention will be described in detail based on preferred embodiments with reference to the drawings as appropriate.

FIG. 1 shows a tire 4 that has been vulcanized and molded together with a tire vulcanizing device 2. The vulcanizing device 2 includes a mold 6, a bladder 8, an upper plate 10, a lower plate 12, a large number of sectors 14, an actuator 16, an upper platen board 18, a lower platen board 20, and a puncture detecting device. 22 and 22. Although not shown, the vulcanization device 2 further includes a lift table, a press table, a control device, and an alarm device.

The vulcanization device 2 of FIG. 1 is installed with the axial direction being the vertical direction. In this vulcanizing device 2, the rightward direction in the left-right direction in FIG. 1 is the radially inward direction, and the direction perpendicular to the paper surface is the circumferential direction.

The mold 6 includes a large number of segments 24, an upper side plate 26, a lower side plate 28, an upper bead ring 30 and a lower bead ring 32. The vulcanization device 2 in FIG. 1 shows a closed state in which the mold 6 is closed.

In FIG. 1, a large number of segments 24 are arranged in the circumferential direction and have a ring shape. Usually, a ring shape is formed by 3 to 20 segments 24, but the number of segments 24 is not particularly limited. The segment 24 mainly forms the tread surface of the tire 4.

The upper side plate 26 is located inside the segment 24 in the radial direction. The upper side plate 26 is in contact with the upper end portion (one end portion in the axial direction) of the segment 24. The lower side plate 28 is located inside the segment 24 in the radial direction. The lower side plate 28 is in contact with the lower end of the segment 24 (the other end in the axial direction). Each of the upper side plate 26 and the lower side plate 28 has a ring shape. The upper side plate 26 and the lower side plate 28 mainly form the axial outer surface of the tire 4. The upper side plate 26 and the lower side plate 28 are a pair of side plates of the present invention.

The upper bead ring 30 is located inside the upper side plate 26 in the radial direction. The upper bead ring 30 is in contact with a radially inner portion of the upper side plate 26. The lower bead ring 32 is located inside the lower side plate 28 in the radial direction. The lower bead ring 32 is in contact with a radially inner portion of the lower side plate 28. Each of the upper bead ring 30 and the lower bead ring 32 has a ring shape. The upper bead ring 30 and the lower bead ring 32 mainly form the outer surface around the bead of the tire 4.

The bladder 8 is arranged inside the mold 6. The bladder 8 is filled with a heating and pressurizing medium, for example, steam, so that the bladder 8 can be expanded and the steam can be discharged and contracted. Inflated bladder 8 is shown in FIG. The bladder 8 extends along the segment 24, the upper side plate 26, the lower side plate 28, the upper bead ring 30, and the lower bead ring 32. The bladder 8 is in contact with the upper bead ring 30 and the lower bead ring 32, and the mold 6 and the bladder 8 form a cavity 34.

The upper plate 10 is located on the upper side plate 26. The upper side plate 26 is fixed to the upper plate 10. The upper plate 10 is movable in the vertical direction by an upper plate driving unit (not shown). The lower plate 12 is located below the lower side plate 28. The lower side plate 28 is fixed to the lower plate 12. By moving the upper plate 10 in the vertical direction, the distance between the upper side plate 26 and the lower side plate 28 can be changed.

Each sector 14 has an inner peripheral surface 14a, an outer peripheral surface 14b, a lower surface 14c and an upper surface 14d. The segment 24 is attached to the inner peripheral surface 14 a of the sector 14. The segment 24 is fixed to the sector 14. The outer peripheral surface 14b is inclined from the inside to the outside in the radial direction from the upper side to the lower side. The outer peripheral surface 34b is in contact with the actuator 16. The sector 14 is attached to the actuator 16. Although not shown, the sector 14 is formed with an engagement groove recessed from the outer peripheral surface 14b. The engagement groove extends from the inside to the outside in the radial direction from the upper side to the lower side.

The actuator 16 includes an actuator body 36 and an actuator ring 38. An actuator ring 38 is mounted on the actuator body 36. The actuator ring 38 is fixed to the actuator body 36.

The actuator ring 38 has a ring shape. The actuator ring 38 is formed with a groove 40 as a flow channel that is recessed from the inner peripheral surface 38a. The actuator ring 38 is formed with a communication hole 42 that communicates from the groove 40 to the upper surface 38b which is the outer surface of the actuator ring 38.

The actuator body 36 has a ring shape. A taper surface 36 a is formed on the inner circumference of the actuator body 36. The tapered surface 36a is inclined from the inside toward the outside in the radial direction from the upper side to the lower side. The tapered surface 36a is slidable on the outer peripheral surface 14b of the sector 14. Although not shown, the actuator body 36 includes an engaging portion that projects inward in the radial direction from the tapered surface 36a.

Although not shown, the engaging portion of the actuator body 36 is engaged with the engaging groove of the sector 14. As a result, the sector 14 is attached to the actuator body 36. The outer peripheral surface 14b of the sector 14 and the taper surface 36a of the actuator body 36 are slidable.

The upper platen board 18 is located above the actuator 16. The actuator 16 is attached to the upper platen board 18. The upper platen board 18 is attached to an elevator (not shown). The upper platen board 18 is movable in the up-down direction by an elevating table as a drive unit. The upper platen board 18 includes a communication hole 44 that communicates from the upper surface 18a to the lower surface 18b. The communication hole 44 communicates with the communication hole 42 of the actuator ring 38 (actuator 16). The lower platen board 20 is located below the lower plate 12. The lower plate 12 is attached to the lower platen board 20. The lower platen board 20 is fixed to a press table (not shown).

The puncture detection device 22 includes a sensor box 22a and a sensor housed in the sensor box 22a. The sensor box 22a is connected to the communication hole 44. This sensor has a function of detecting the heating and pressurizing medium leaking from the bladder 8. An example of this sensor is a humidity sensor that detects vapor as a heating and pressurizing medium. In the vulcanization device 2, the communication hole 42 and the communication hole 44 function as a ventilation hole 46 that connects the groove 40 and the puncture detection device 22. The vent hole 46 may connect the groove 40 and the puncture detection device 22. The vent hole 46 may be composed of only the communication hole 42 of the actuator 16, or may be composed of a combination of the communication hole 42 and the communication hole 44 with another communication hole or a pipe.

FIG. 2 shows an exploded view of a part of the mold 6 in the closed state. In the mold 6, the plurality of sectors 14 are arranged in the circumferential direction and have a ring shape. The plurality of segments 24 are arranged in the circumferential direction and have a ring shape. In this mold 6, nine segments 24 are arranged in the circumferential direction to form a ring shape.

Each segment 24 includes an inner peripheral surface 24a facing inward in the radial direction, an outer peripheral surface 24b facing outward in the radial direction, an end surface 24c facing in one circumferential direction, and an end surface 24d facing in the other circumferential direction. The outer peripheral surface 24b abuts on the sector 14 and is attached to the sector 14. In the mold 6 of FIG. 2, the end faces 24c and 24d face each other between the adjacent segments 24. The end surface 24c and the end surface 24d are in contact with each other.

As shown in FIG. 3A, in the closed state of the mold 6, the inner peripheral surface 38a of the actuator ring 38 as the inner peripheral surface of the actuator 16 and the outer peripheral surface 10a of the upper plate 10 face each other. .. A slight gap is formed between the inner peripheral surface 38a and the outer peripheral surface 10a.

The double-headed arrow H in FIG. 3A represents the vertical width of the groove 40. The vertical width H is the distance from the inner peripheral surface 38a of the actuator ring 38 to the bottom surface 40a of the groove 40. The vertical width H is measured as a linear distance in the radial direction. A double-headed arrow D represents the inner diameter of the communication hole 42. The communication hole 42 is formed of a communication hole 42a extending in the radial direction and a communication hole 42b extending in the axial direction, and the communication hole 42a and the communication hole 42b are formed with an inner diameter D. The double-headed arrow W in FIG. 3B represents the lateral width of the groove 40. The width W is measured as a linear distance in a direction perpendicular to the axial direction and perpendicular to the radial direction.

The control device has a function of controlling the lifting platform and the upper plate driving unit. The control device has a function of controlling the puncture detection device 22. The puncture detection device 22 has a function of detecting a puncture of the bladder 8. The puncture detection device 22 has a function of outputting a puncture detection signal to the control device. The control device has a function of receiving this puncture detection signal and a function of outputting an operation signal to the alarm device. The alarm device includes an alarm light and an alarm speaker. The alarm device has a function of receiving an operation signal, a function of turning on an alarm lamp, and a function of emitting an alarm sound from an alarm speaker.

In FIG. 4A, the upper plate 10 is located above. The upper side plate 26 is located above the upper plate 10 as well. The upper side plate 26 and the lower side plate 28 are arranged apart from each other. The upper platen plate 18 is located further above the upper plate 10. The actuator 16 is located above the upper platen board 18. The sector 14 moves along the tapered surface 36 a of the actuator 16, and the sector 14 is located below and radially outside the actuator 16. Together with this sector 14, the segment 24 is located radially outside. The segments 24 arranged in the circumferential direction are arranged at intervals in the circumferential direction. In this vulcanizing apparatus 2, the mold 6 is in an open state in which it is opened.

In FIG. 4B, the upper plate 10 is located below. The upper side plate 26 is located below together with the upper plate 10. The upper side plate 26 and the lower side plate 28 are arranged near each other. The upper platen board 18 is located below. The actuator 16 is located below the upper platen board 18. The sector 14 is in contact with the upper surface 12a of the lower plate 12. The sector 14 moves along the tapered surface 36 a of the actuator 16 and is located above and radially inside the actuator 16. With this sector 14, the segment 24 is located radially inward. The segments 24 arranged in the circumferential direction abut each other and are arranged in a ring shape. The outer peripheral surface of the upper side plate 26 is in contact with the inner peripheral surface of the upper end portion (one end portion in the axial direction) of the segment 24. The outer peripheral surface of the lower side plate 28 is in contact with the inner peripheral surface of the lower end portion (the other end portion in the axial direction) of the segment 24. In this vulcanizer 2, the mold 6 is in a closed state.

A method of manufacturing the tire 4 using the vulcanizing apparatus 2 will be described with reference to FIGS. 1 to 4. The method for manufacturing the tire 4 includes a preparation step, a charging step, a mold closing step, an inflation step, a pressurizing step, an exhausting step, a mold opening step and a removing step.

In the preparation step, the vulcanizer 2 and the raw cover are prepared. In this preparatory step, the mold 6 is in an open state as shown in FIG. In the raw cover insertion step, the raw cover is placed on the mold 6 in the open state. In the mold closing step, the mold 6 is closed as shown in FIG.

In the inflation step, the bladder 8 is filled with steam as a heating and pressurizing medium, and the bladder 8 expands. In the pressurizing step, the bladder 8 is filled with an inert gas to pressurize the bladder 8. Thereby, the raw cover is vulcanized and molded according to the shape of the cavity 34 of the mold 6. The tire 4 is formed from this raw cover.

In the exhaust step, the bladder 8 exhausts the inert gas and the vapor. In the mold opening step, the mold 6 is opened. In the take-out step, the tire 4 is taken out from the mold 6. In this way, the tire 4 is obtained from the raw cover.

In the method for manufacturing the tire 4, the puncture of the bladder 8 is inspected in the mold opening step. When the mold 6 is opened from the closed state, the puncture detection device 22 detects the vapor flowing into the groove 40. The puncture detection device 22 detects a puncture of the bladder 8. The puncture detection device 22 outputs a puncture detection signal to the control device when detecting the puncture of the bladder 8. The control device receiving the puncture detection signal outputs an operation signal to the alarm device. The alarm device turns on an alarm light and emits an alarm sound. The vulcanization device 2 informs the worker of the puncture of the bladder 8 with an alarm light and an alarm sound.

In this vulcanizing device 2, a groove 40 is formed as a flow channel recessed from the inner peripheral surface 38a of the actuator ring 38 (actuator 16). The vertical width H of the groove 40 is larger than the radial width of the gap formed between the outer peripheral surface 10a and the inner peripheral surface 38a. Steam is allowed to easily flow into the groove 40 from other gaps formed in the vulcanizer 2. Since the puncture detection device 22 is connected to this groove 40, it is easy to detect the puncture of the bladder 8. Further, since the groove 40 is arranged above the mold 6, steam easily flows in. The vulcanization device 2 is excellent in the accuracy of detecting a flat tire of the bladder 8.

In the vulcanizer 2, a groove 40 is formed which is recessed from the inner peripheral surface 38a of the actuator ring 38 (actuator 16). The groove 40 is formed along the gap between the outer peripheral surface 10a and the inner peripheral surface 38a. This facilitates the formation of the groove 40. In this vulcanizer 2, the groove 40 is formed in the actuator ring 38 (actuator 16), but the present invention is not limited to this. The groove 40 may be recessed from the outer peripheral surface 10a of the upper plate 10 or may be recessed from the outer peripheral surface 10a and the inner peripheral surface 38a.

The vulcanization device 2 having a large vertical width H of the groove 40 can easily detect a puncture of the bladder 8. From this viewpoint, the vertical width H is preferably 1 mm or more, more preferably 5 mm or more, and particularly preferably 10 mm or more. The vertical width H has no particular upper limit, but is, for example, 30 mm or less. From the same viewpoint, the lateral width W of the groove 40 is preferably 3 mm or more, more preferably 10 mm or more, and particularly preferably 20 mm or more. The lateral width W is, for example, 40 mm or less.

Further, from the same viewpoint, the diameter D of the communication hole 42 is preferably 3 mm or more, more preferably 10 mm or more, and particularly preferably 20 mm or more. This diameter D is, for example, 40 mm or less. Further, it is preferable that the diameter of the communication hole 44 is also the same as the diameter D of the communication hole 42. In other words, the diameter of the ventilation hole 46 is preferably 3 mm or more, more preferably 10 mm or more, and particularly preferably 20 mm or more. This diameter D is, for example, 40 mm or less.

The actuator 16 includes an actuator body 36 and an actuator ring 38. In this actuator 16, since the groove 40 and the communication hole 42 are formed in the actuator ring 38, the groove 40 and the communication hole 42 are easily formed. The actuator 16 does not necessarily have to include the actuator body 36 and the actuator ring 38. The groove 40 and the communication hole 42 may be formed in the integral actuator 16.

In the method for manufacturing the tire 4 using the vulcanizing device 2, the puncture of the bladder 8 is inspected in the mold opening step, but the invention is not limited to this. For example, the blowout of the bladder 8 may be inspected in the inflation step. For example, in the inflation process, the bladder 8 is filled with steam and expanded with the mold 6 slightly opened. The steam leaked in this state is allowed to escape to the outside of the mold 6. Then, the puncture of the bladder 8 may be detected by detecting the steam flowing into the groove 40.

Hereinafter, the effects of the present invention will be clarified by examples, but the present invention should not be limitedly interpreted based on the description of the examples.

[Example 1]
The vulcanization apparatus shown in FIG. 1 was prepared. In this vulcanizer, the vertical width H of the groove was 10 mm, the horizontal width W was 20 mm, and the diameter D of the communication hole was 20 mm. The total distance L of the groove and the vent hole was L1. Bladder puncture detection accuracy was tested using 10 vulcanizers with flat bladders. The results are shown in Table 1. This puncture detection rate is expressed as an index. This index has a detection accuracy of 50 in the comparative example. The larger the numerical value of this index, the higher the detection accuracy, which is preferable.

[Comparative example]
The detection accuracy of the puncture of the bladder was tested in the same manner as in Example 1 except that a conventional vulcanizing device was prepared. The results are shown in Table 1.

[Examples 2 and 3]
The bladder puncture detection accuracy was tested in the same manner as in Example 1 except that the groove vertical width H, horizontal width W, communication hole diameter D, and flow path distance L were set as shown in Table 1. It was In these examples, the total length of the flow path (distance L) was set to be twice as long as the distance L1 in the first embodiment. The results are shown in Table 1.

As shown in Table 1, the evaluation of the example is higher than that of the comparative example. From this evaluation result, the superiority of the present invention is clear.

2... Vulcanizing device 4... Tire 6... Mold 8... Bladder 10... Upper plate 14... Sector 16... Actuator 22... Punk detector 24... Segment 26... Upper side plate 36... Actuator body 38... Actuator ring 40... Groove 42... Communication hole, communication hole 46... Vent hole

Claims (5)

A plurality of segments that form the tread surface of the tire, and a mold that includes a pair of side plates that form the outer surface of the tire in the axial direction,
A sector to which the segment is attached,
An actuator that moves the sector and the segment in the radial direction by moving in the axial direction;
An upper plate that moves one side plate of the pair of side plates in the axial direction by moving in the axial direction;
A bladder that expands and contracts with a heating and pressurizing medium,
It is provided with a puncture detection device for detecting the leakage of the heating and pressurizing medium from the bladder,
In a closed position in which the mold is closed, the outer peripheral surface of the upper plate and the inner peripheral surface of the actuator are opposed to each other,
It is provided with a flow channel recessed from the outer peripheral surface or the inner peripheral surface,
A tire vulcanizing device, wherein the flow path communicates with the puncture detecting device. The tire vulcanizing device according to claim 1, wherein the flow path is formed by a groove recessed from an inner peripheral surface of the actuator. The tire vulcanizing apparatus according to claim 2, wherein the groove has a vertical width of 1 mm or more and a lateral width of 3 mm or more. It has a ventilation hole that communicates the flow passage and the puncture detection device,
The tire vulcanizing apparatus according to claim 3, wherein the diameter of the ventilation hole is 3 mm or more. It has a ventilation hole that communicates the flow passage and the puncture detection device,
The actuator comprises an actuator body and an actuator ring mounted on the actuator body,
The tire vulcanizing device according to any one of claims 1 to 4, wherein the flow path and the vent hole are formed in the actuator ring.

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