JPS645527B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to improvements in tire vulcanizing equipment.

Conventionally, vulcanization of tires has been carried out using a vulcanizing apparatus as shown in cross-section in FIG.

To explain the outline of this device, reference numeral 1 denotes a bladder supported by an upper clamp ring 2 and a lower clamp ring 3, and is shown in an expanded state by supply of a vulcanizing medium.

(Please note that the rings around the upper and lower clamp rings,
Illustrations of molds, tires, etc. are omitted. ) The upper clamp ring 2 is supported by the center post 4. 5 is a bag cylinder and 6 is a bag cylinder head. The lower clamp ring 3 is supported by the bag cylinder 5. 7 is a baffle plate supported by the lower clamp ring 3, and this baffle plate 7 and the lower clamp ring 3
In between, a supply port 9 of a steam or gas supply pipe 8 and a discharge port 11 of a discharge pipe 10 are provided at a position opposite thereto.

Note that 12 is a diaphragm valve operated by air pressure sent from a solenoid valve directly connected to a timer (not shown).

Vulcanization of the tire (not shown) in the vulcanization chamber by such a device includes, for example, a shaping process,
It is completed through known operational steps such as a steam process, a gas process, and an exhaust process.

However, a drawback of this method is that both steam and gas are supplied from the same supply port 9.

That is, when the gas following the steam process is supplied from the supply port 9 located below the vulcanization chamber 13, the specific gravity of the gas is greater than that of the steam, so that the gas is supplied to the lower part 14 in the vulcanization chamber 13. It has a strong tendency to accumulate, making it difficult to mix uniformly with the steam filling the chamber.

Therefore, steam accumulates in the upper part 15 of the vulcanization chamber, and as a result, the upper part 15 is 7 to 8 degrees Celsius higher than the standard temperature of the vulcanization chamber, and the lower part 14 is 7 to 8 degrees higher than the standard temperature of the vulcanization chamber.
It has been pointed out that a temperature difference of 15 to 16° C. occurs between the upper and lower portions of the tire sidewall, making it difficult to obtain a uniformly vulcanized tire.

The inventor of the present invention arrived at this invention as a result of various studies in order to find a vulcanizing device that can eliminate the drawbacks of tire vulcanization using conventional vulcanizing devices and can always perform uniform vulcanization. be.

That is, this invention supplies steam and gas to a tire set in a vulcanizing chamber from separate supply ports, and in particular uses a baffle plate of a new structure to increase the gas supply injection height to a higher level than the steam supply port. The first feature is that the gas is supplied from the gas supply port at the position, and furthermore, in order to give directionality to the gas supply injection using the baffle plate, the baffle plate has a thick taper on its upper surface periphery, and an upper clamp ring. The second feature is that the baffle plate is installed so that the gap between the baffle plate and the top surface of the baffle plate is 5 to 10 mm.

Hereinafter, this invention will be explained based on FIGS. 2 to 5 showing one embodiment thereof.

In Fig. 2, 21 is the upper clamp ring 2.
2 and a lower clamp ring 23. (The rings, molds, tires, etc. around the upper and lower clamp rings are not shown in the illustration.) 24 is a baffle plate, and the lower clamp ring 2
3, and its shape is tapered with a thick peripheral edge on the upper surface. Due to this taper, the gas is injected toward the vicinity of the upper portion 32 of the vulcanization chamber 33 as indicated by the black arrow.

The baffle plate 24 and the lower clamp ring 23
The supply port 27 of the steam supply pipe 26 passing through the inside of the bag cylinder 25 is arranged between the supply port 27 of the steam supply pipe 26 which passes through the inside of the bag cylinder 25, and the supply port 27 of the gas supply pipe 28 which also passes through the inside of the bag cylinder 25 is arranged at the upper part of the baffle plate 24 at a position opposite to this. A supply port 29 is provided. This gas supply pipe 28 also serves as an exhaust pipe during the latter half of the vulcanization process, such as exhaust and vacuuming. 30 is a diaphragm valve.

To perform tire vulcanization using a vulcanizing device having such a structure, for example, first steam (2Kg/cm ² ) is supplied into the vulcanization chamber 33 from the supply port 27 for shaping, and then steam (15Kg/cm 2 ) is supplied into the vulcanization chamber 33 for shaping. cm ² ) is also supplied from the supply port 27 and heated, and then the gas from the gas supply pipe 28 is supplied from the supply port 29 to the baffle plate 24.
It is supplied through the gap between the upper part and the upper clamp ring 22.

As a result, the gas is injected into the upper part 32 of the vulcanization chamber 33 filled with steam, so that the steam and gas are sufficiently mixed, and the downward settling speed of the gas can be slowed down, resulting in the formation of tire sidewalls. The temperature difference between the upper and lower parts of the tire can be reduced to about 5 to 6 DEG C., thereby preventing over- or under-vulcanization of the tire sidewall, and more uniform vulcanization.

The baffle plate 24 has a tapered shape with a thick upper peripheral edge as shown in FIG. 2, and the appropriate gap between the upper clamp ring 22 and the baffle plate 24 is 5 to 10 mm. It is preferable that it does not adversely affect the bladder life when it hits the bladder during contraction (vacuum).

The reason why the gap between the upper clamp ring 22 and the baffle plate 24 is set to 5 to 10 mm is because if it is less than 5 mm, the directionality when gas is ejected is small, and if the gap is too small, it is easy to get clogged, so if it exceeds 10 mm, the taper angle should be adjusted. This is because it has to be made quite tight.

Note that instead of the baffle plate 24, a gas supply port 29
A pipe (not shown) that is loosely continuous and angled in the direction of the black arrow may be used.

Above, based on FIG. 2, the embodiment in which the gas supply injection is performed from a high position toward the upper part 32 of the vulcanization chamber 33 has been described. By devising the supply method, it is possible to reduce the temperature difference between the upper and lower parts of the tire sidewall.

That is, for example, first steam (2 kg/cm ² ) is supplied for shaping, and then steam (5 kg/cm 2 ) is supplied again.
Kg/cm ² ) is supplied from the supply port 27 for 30 seconds to heat it, and then gas (10Kg/cm ² ) is supplied from the supply port 29 for 30 seconds.
2 seconds, then steam (15Kg/cm ² ) is again supplied from the supply port 27 for 6 minutes, and then gas (21
Kg/cm ² ) is supplied from the supply port 29, then exhausted from the discharge port 29, and finally vacuumed to complete one cycle of the vulcanization process.

In another example, the above alternating supply of steam and gas is performed by supplying gas (5Kg/cm ² ) for 30 seconds, then supplying steam (15Kg/cm ² ) for 6 minutes, then supplying gas (21Kg/cm ² ) for 7 minutes. It may be supplied for minutes.

In this way, if the steam and gas supply positions shown in Fig. 2 are used, and if the steam and gas are supplied in the above-mentioned alternate manner, the effect becomes even more remarkable. can be reduced to about 2-3°C.

Note that the opening 34 of the steam supply port 27 of this invention
The opening 35 of the gas supply port 29 may be provided at one location in the circumferential direction as shown in FIG.
As shown in the figure, several to ten holes with a diameter of 2 to 6 mm are provided in the circumferential direction.

Next, the apparatus of the present invention, as shown in FIG. 2, has a case in which steam is supplied from the supply port at the bottom of the baffle plate, and gas is supplied from the gas supply port at the top of the baffle plate;
We conducted an actual tire vulcanization test using a conventional device in which both steam and gas are supplied from the supply ports at the bottom of the baffle plate. When the vulcanization temperature difference R between the upper and lower parts of the part was investigated, the results shown in FIGS. 5A and 5B were obtained.

In addition, in this test, the device of the present invention shown in FIG. 5A is a device in which 15 kg of steam was supplied from the steam supply port at the bottom of the baffle plate, and then 21 kg of gas was supplied from the gas supply port at the top of the baffle plate. Fig. 5B shows steam 15Kg, gas
15 kg was supplied sequentially from the supply port at the bottom of the baffle plate.

From FIG. 5, it can be seen that A according to the present invention has a temperature difference R = 4 even after 1 to 5 minutes have passed after switching from steam to gas.
~8°C, and in particular even after 5 minutes of switching to gas, the temperature difference was only 4°C.

On the other hand, in B using the conventional device, the temperature difference R is
The temperature was very high at 13 to 17°C, and it was confirmed that a more uniform tire vulcanization state could be obtained with the apparatus of the present invention.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a conventional device used for tire vulcanization, Fig. 2 is a sectional view of a tire vulcanizing device of the present invention, Fig. 3 is a sectional view of the opening of the steam supply port, and Fig. 4 is a gas supply FIGS. 5A and 5B, which are cross-sectional views of the mouth opening, are charts showing the temperature difference between the upper and lower sidewalls of tires according to the present invention and the conventional apparatus. 21... Bladder, 22... Upper clamp ring, 23... Lower clamp ring, 24... Baffle plate, 27... Steam supply port, 29... Gas supply port.

Claims (1)

[Claims] 1. In a vulcanizing device that vulcanizes a green tire by supplying a vulcanizing medium such as steam or gas into a mold in which a green tire is set, an upper clamp ring supported by a center post and an upper clamp ring supported by a center post are used. The bladder is supported by a lower clamp ring supported by a bag cylinder, and a baffle plate having a slight gap with the upper clamp ring is installed between the upper clamp ring and the lower clamp ring, and the gas supply port is connected to a gas other than gas. Installed at a higher position than the vulcanization medium supply port,
A tire vulcanizing device characterized in that gas is injected through the gap. 2 Set the gap between the baffle plate and the upper clamp ring to 5~
Claim 1 characterized in that the diameter is 10 mm.
The tire vulcanizing device described in Section 1. 3. The tire vulcanizing device according to claim 1, wherein the baffle plate has an upper surface tapered with a thick peripheral edge.