JP2002067040A - Method and apparatus for detecting puncture of vulcanizing bladder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely detect a puncture of a vulcanizing bladder 29 even when a leakage amount of a vulcanizing gas is small. SOLUTION: When the vulcanizing bladder 29 is punctured, the vulcanizing gas is guided to a passage 31. Then, the gas is diffused in an air fully filled in the passage 31 so that concentrations of the gases are changed. Then, gas concentrations are detected by a gas detecting sensor 35, its change is detected by a controller 37, and whether a puncture occurs or not is judged. Here, even when the exhausted gas is small, the concentrations of the gases are surely changed by the diffusion, and hence the puncture can be detected surely.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a puncture detection method and apparatus for detecting puncture of a vulcanized bladder.

[0002]

2. Description of the Related Art As a conventional method and apparatus for detecting puncture of a vulcanized bladder, for example, a method described in JP-A-53-139682 is known. It has a passage communicating with the vulcanization bladder, and a thermistor provided in the middle of the passage. When the vulcanization bladder punctures, the high-temperature vulcanization gas in the vulcanization bladder flows out to the outside between the vulcanization bladder and the tire and through a passage communicating therewith. Heats a thermistor provided in the middle of the passage, so that such heating is detected to detect puncture of the vulcanized bladder.

[0003]

However, in such a conventional vulcanizing bladder puncture detecting method / apparatus, when the vulcanizing bladder has a small puncture hole and a small amount of vulcanizing gas leaks. Means that the vulcanized gas absorbs heat to the surroundings before it reaches the thermistor and the temperature decreases, and the amount of heat is insufficient to heat the thermistor, which makes puncture detection inaccurate. There is a problem.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vulcanized bladder puncture detection method and apparatus that can reliably detect vulcanized bladder puncture even when the amount of vulcanized gas leakage is small.

[0005]

SUMMARY OF THE INVENTION The purpose of the invention is as follows.
Then, the vulcanization gas in the vulcanization bladder that has flowed between the vulcanization bladder and the tire due to the puncture of the vulcanization bladder is led to a passage filled with air, and the concentration of each gas in the passage is increased. While changing the concentration of any one of the gases by the gas detection sensor, when the concentration of the gas changes, by the vulcanized bladder puncture detection method to determine that the vulcanized bladder punctured,

Secondly, a passage communicating between the tire and the vulcanizing bladder and being filled with air therein, and provided in the middle of the passage to detect the concentration of any gas in the passage. A gas detection sensor, and a control unit that determines whether or not the vulcanized bladder has been punctured based on a detection signal from the gas detection sensor, and the vulcanized gas in the vulcanized bladder is reduced by the puncture of the vulcanized bladder. When the concentration of each gas in the passage changes by being guided in the passage, the gas concentration is detected by the gas detection sensor, and the detection signal is output to the control unit, whereby the puncture of the vulcanized bladder is performed. Can be attained by a vulcanized bladder puncture detecting device configured to detect the puncture.

When a puncture occurs in the vulcanized bladder, the high-temperature and high-pressure vulcanized gas in the vulcanized bladder flows out between the tire and the vulcanized bladder, and then communicates between the tire and the vulcanized bladder. You are led into the passage. Here, the passage is filled with air. Since the inflowing vulcanizing gas diffuses into the air, the concentration of each gas constituting the air and the concentration of the vulcanizing gas change.

Then, the concentration of any one of the gases is detected by a gas detection sensor provided in the middle of the passage, and a detection signal is output to the control unit.
At this time, since the value of the detection signal output to the control unit changes due to the above-described density change, the control unit determines that the vulcanization bladder has been punctured. Here, even if the amount of the vulcanized gas flowing out of the vulcanized bladder is small, the concentration of each gas changes without fail due to the above-described diffusion, so that the puncture of the vulcanized bladder can be reliably detected.

Further, according to the third aspect of the present invention, the existing peeling air supply passage can be used as it is as a puncture detection passage, so that it is not necessary to newly provide a passage, thereby simplifying the structure. It can be inexpensive. Further, when steam is used as the vulcanizing gas, the gas is condensed due to a decrease in temperature, so that the change in the gas concentration becomes unclear. However, if a gas that does not condense as described in claim 4 is used, Thus, puncture detection is ensured.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 11 denotes a tire vulcanizing device. The vulcanizing device 11 has a stationary lower base 12, and a lower platen 13 is fixed to an upper surface of the lower base 12. On the upper surface of the lower platen 13, a lower vulcanization mold 15 provided with a molding surface 14 for molding the lower half of the unvulcanized tire T bead, side wall and tread is mounted.

Above the lower base 12, an upper base 17 which is moved up and down by elevating means (not shown) is installed, and an upper platen 18 is fixed to a lower surface of the upper base 17. An upper vulcanization mold 19 that is paired with the lower vulcanization mold 15 is fixed to the lower surface of the upper platen 18.
Is provided with a molding surface 20 for molding the upper bead portion, the sidewall portion, and the upper half of the tread portion of the unvulcanized tire T.

Reference numeral 23 denotes a vertically extending cylindrical body loosely fitted to the center of the lower base 12 and the lower platen 13. The upper end of the cylindrical body 23 is in contact with the inner end of the lower vulcanization mold 15. The lower clamp ring 24 that is in contact is fixed. Reference numeral 25 denotes a vertically extending center post which is inserted into the cylindrical body 23 so as to be able to move up and down, and an upper clamp ring 26 which can abut the inner end of the upper vulcanization mold 19 at the upper end of the center post 25. Has been fixed. When the upper base 17 is lowered and the upper vulcanization mold 19 contacts the lower vulcanization mold 15 and the upper clamp ring 26, the lower and upper vulcanization molds 15, 19
The vulcanization mold 27 composed of
17, Upper platen 18, Upper vulcanization mold 19, Center post
25, a closed space 28 surrounded by the upper clamp ring 26 is formed.

Reference numeral 29 denotes a bendable vulcanization bladder having a lower end portion held in a lower clamp ring 24 and an upper end portion held in an airtight state by an upper clamp ring 26. The vulcanization bladder 29 has a high temperature and high pressure inside. When an inert gas such as a vulcanized gas, for example, a nitrogen gas or an argon gas, is injected, it expands into a donut shape in the unvulcanized tire T, and the unvulcanized tire T is closed and the upper vulcanization mold is closed. The vulcanized tire T is vulcanized while being pressed against the molding surfaces 14 and 20 of 15 and 19.

Reference numeral 31 denotes a separation air supply passage formed by laying a pipe. One end of the passage 31 extends through the upper base 17 into the closed space 28, and the upper vulcanization mold 19 One end ends near the boundary between the upper clamp ring 26 and the upper clamp ring 26. Here, even when the vulcanizing mold 27 is closed, there is a slight gap at the boundary between the upper vulcanizing mold 19 and the upper clamp ring 26, and one end of the passage 31 is vulcanized through this gap. It can communicate between the bladder 29 and the tire T.

An air supply source 32 is connected to the other end of the passage 31, so that the inside of the passage 31 is always filled with air. Then, from the air supply source 32, the tire T
When the vulcanization gas is discharged from the vulcanization bladder 29 after the vulcanization of the vulcanization is completed, air of a predetermined pressure is supplied between the vulcanization bladder 29 and the vulcanized tire T through the passage 31, and The peeling of the bladder 29 from the vulcanized tire T is promoted.

If the passage 31 is constituted by the peeling air supply passage as described above, the existing peeling air supply passage can be used as it is as a puncture detection passage, so that it is not necessary to newly provide a passage. Can be made simple and inexpensive.

In the middle of the passage 31, in this embodiment, the passage
A gas detection sensor 35 is housed at one end of the gas sensor 31. The gas detection sensor 35 detects the concentration of any gas in the passage 31. As such a gas detection sensor 35,
For example, a metal oxide semiconductor sensor for detecting the concentration of oxygen gas can be used.

One end of a lead wire 36 extending along the passage 31 is connected to the gas detection sensor 35, and the other end of the lead wire 36 is connected to a vulcanizing bladder based on a detection signal from the gas detection sensor 35. Control unit that determines whether 29 has punctured
37 is connected. That is, the control unit 37 uses the detection signal output from the gas detection sensor 35 and a reference signal stored in advance (when the oxygen gas concentration is a normal value, the concentration of the oxygen gas is detected by the gas detection sensor 35). When the former becomes larger than the latter due to a decrease in the oxygen gas concentration, it is determined that the vulcanized bladder 29 has punctured.

Since a plurality of tire vulcanizing apparatuses 11 as described above are provided, passages 31 are also provided to other tire vulcanizing apparatuses.
Are connected, and a gas detection sensor 35 similar to that described above is also provided in the middle of these passages 40.

Next, the operation of the embodiment of the present invention will be described. When vulcanizing the unvulcanized tire T using the tire vulcanizing device 11 described above, the upper base 17, the upper platen 18,
When the upper vulcanization mold 19 is located at the upper limit, the unvulcanized tire T is carried into the lower vulcanization mold 15 and placed horizontally, and the center post 25 projecting upward is lowered. A low-pressure vulcanizing gas is supplied into the vulcanized bladder 29 while expanding the vulcanized bladder 29 into a donut shape in the unvulcanized tire T.

Thereafter, the upper base 17, the upper platen 18, and the upper vulcanization mold 19 are lowered until the upper vulcanization mold 19 contacts the lower vulcanization mold 15 and the upper clamp ring 26, and the vulcanization mold 27
And one end of the passage 31 is positioned near the boundary between the upper vulcanization mold 19 and the upper clamp ring 26 in the closed space 28.

Next, when a high-temperature, high-pressure vulcanizing gas is supplied into the vulcanized bladder 29, the vulcanized bladder 29 moves down the unvulcanized tire T, and forms the molding surfaces 14, 20 of the upper vulcanization molds 15, 19. Vulcanized while being pressed against to obtain a vulcanized tire T.

If a puncture occurs in the vulcanized bladder 29 during vulcanization as described above, the vulcanized gas in the vulcanized bladder 29 is discharged from the vulcanized bladder 29 and the unvulcanized tire T
However, since the vulcanized bladder 29 is strongly pressed against the tire T by the high-pressure vulcanized gas, the leaked vulcanized gas hardly flows into the closed space 28.

Next, when the vulcanization of the tire T is completed, the vulcanized gas is discharged from the vulcanized bladder 29. At this time, the pressing force of the vulcanized bladder 29 against the vulcanized tire T by the vulcanized gas is reduced. Since the vulcanized bladder 29 starts to peel off from the inner surface of the vulcanized tire T when it becomes weak, the vulcanized gas flowing out between the vulcanized bladder 29 and the vulcanized tire T described above is
It is guided to the closed space 28 and the passage 31 through a small gap between the upper vulcanization mold 19 and the upper clamp ring 26.

Here, the passage 31 is filled with air. However, since the above-mentioned vulcanized gas which has flowed into the air is diffused, each gas constituting the air, for example, oxygen gas, carbon dioxide gas, etc. Etc., while the vulcanizing gas, for example,
The concentration of nitrogen gas, argon gas, etc. increases. And
Of these gases, the concentration of oxygen gas is
It is detected by the gas detection sensor 35 and the detection signal is
Output to 37. Here, if the above-mentioned inert gas which does not condense as the vulcanizing gas is used, since it does not condense due to a decrease in temperature unlike water vapor, puncture detection is ensured.

As a result, the control unit 37 compares the detection signal from the gas detection sensor 35 with a reference signal stored in advance. At this time, the former value is changed to the latter value due to a decrease in the oxygen gas concentration. The control unit 37
Determines that the vulcanized bladder 29 has punctured. As described above, even if the amount of the vulcanized gas flowing out of the vulcanized bladder 29 is small, the concentration of each gas is surely changed by the above-described diffusion, so that the puncture of the vulcanized bladder 29 can be reliably detected.

On the other hand, when no puncture is generated in the vulcanization bladder 29, the peeling air is supplied from the air supply source 32 through the passage 31 to the vulcanization bladder 29 at a later stage of the discharge of the vulcanization gas from the vulcanization bladder 29. It is supplied between the vulcanized tire T and vulcanized bladder 29
From the vulcanized tire T is promoted. Next, the upper base 17, the upper platen 18, and the upper vulcanization mold 19 are raised to open the vulcanizing mold 27, and the center post 25 is raised to release the vulcanized bladder 29 from within the vulcanized tire T. After being extracted, the vulcanized tire T is carried out of the vulcanizing device 11.

In the above-described embodiment, the concentration of oxygen gas is detected by the gas detection sensor 35. However, in the present invention, the concentration of another type of gas may be detected by the gas detection sensor. Good.

[0029]

As described above, according to the present invention, even when the amount of vulcanizing gas leaking from the vulcanized bladder is small, it is possible to reliably detect the puncture of the vulcanized bladder.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing an embodiment of the present invention.

[Explanation of symbols]

 29 ... vulcanized bladder 31 ... passage 35 ... gas detection sensor 37 ... control unit T ... tire

Claims (4)

[Claims] 1. A vulcanizing gas in a vulcanized bladder which has flowed out between a vulcanized bladder and a tire by puncturing of a vulcanized bladder is guided to a passage filled with air, and A vulcanization method characterized in that the concentration of a gas is changed, and the concentration of any one of the gases is detected by a gas detection sensor, and when the concentration of the gas changes, it is determined that the vulcanization bladder has punctured. A bladder puncture detection method. 2. A passage communicating between a tire and a vulcanization bladder and filled with air therein, and a gas provided in the middle of the passage for detecting a concentration of any gas in the passage. A detection sensor, and a control unit that determines whether or not the vulcanized bladder has punctured based on a detection signal from the gas detection sensor, and the vulcanized gas in the vulcanized bladder passes through the passage when the vulcanized bladder is punctured. When the concentration of each gas in the passage changes, the gas concentration is detected by the gas detection sensor, and the detection signal is output to the control unit, thereby detecting the puncture of the vulcanized bladder. A puncture detecting device for a vulcanized bladder, characterized in that: 3. The vulcanizing bladder according to claim 2, wherein the passage is a peeling air supply passage for supplying air between the vulcanized bladder and the tire after vulcanization to promote peeling of the vulcanized bladder from the tire. Sulfuric bladder puncture detector. 4. The puncture detecting device for a vulcanized bladder according to claim 2, wherein an inert gas is used as said vulcanizing gas.