JPS6184211A - Vulcanization of elastomer article - Google Patents

Abstract

PURPOSE:To improve the suitability of vulcanization by vulcanizing mixed fluid as the pressure and temperature of the fluid are adjusted so as to agree to the conditions of the preset pressure and temperature. CONSTITUTION:The conditions of pressure and temperature suitable to vulcanize an article are provided in advance for the controller 7. When a signal of pressure in a vulcanizing chamber and a signal of temperature of the internal part of the article A are outputted from the sensors 5, 6, the controller 7 operates the automatic regulating valves V1, V2, V3 so as to supply to vulcanizing chamber the mixed fluid having the pressure and the temperature agreeing to each set condition. For example, when the temperature only does not arrive at the set value, the valves V1, V2, V3 are opened. When the pressure exceeds the set value and the temperature comes short of the set value, the valve V3 is opened, the mixed fluid is exhausted, the valve V1 is opened and then vapor is injected. When the pressure only comes short of the set value, as the valves V1, V2 remain to be closed, the valve V2 is opened to supply inert gas into the vulcanizing chamber.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to an elastomer article placed in a vulcanization chamber of a mold,
In particular, the present invention relates to a method of vulcanizing vehicle tires using a mixed fluid obtained by directly mixing a low heat capacity gas and a high heat capacity thermal fluid in a vulcanization chamber.

(Prior art) Vulcanization of elastomer articles such as tires requires appropriate temperature and appropriate pressure, but saturated steam, which has been used as a thermal fluid with a high heat capacity, has a temperature between pressure and temperature. There is a relationship, and there is a disadvantage that the temperature increases at the same time as the pressure is increased, and the pressure also decreases when the temperature is lowered. It was difficult to obtain proper vulcanization because the degree of Ji was excessive and the pressure was insufficient at an appropriate temperature. Therefore, the applicant placed a temperature sensor and a pressure sensor in the vulcanization chamber, directly mixed steam and inert gas in the vulcanization chamber, and controlled the temperature and pressure of the resulting mixed fluid. The invention was conceived of as a method for vulcanizing elastomer articles and was filed in Japanese Patent Application No. 116644/1983. Although this method has made it possible to easily obtain proper vulcanization, it is also possible to indirectly control the vulcanization temperature of elastomer articles by controlling the temperature of the vulcanization medium (mixture). Therefore, it was difficult to determine the appropriate degree of vulcanization.

OBJECTS OF THE INVENTION The present invention solves the above problems and provides a method for vulcanizing elastomeric articles using a fluid mixture of a low heat capacity gas and a high heat capacity thermal fluid mixed directly in a vulcanization chamber. It is an object of the present invention to provide a vulcanization method that can more effectively control the appropriateness of vulcanization.

(Structure of the Invention) The main feature of the present invention is that the elastomer article placed in the vulcanization chamber is heated using a mixed fluid obtained by directly mixing a low heat capacity gas and a high heat capacity thermal fluid in the vulcanization chamber. A method of vulcanization, comprising setting desired pressure and temperature conditions in a controller, placing a temperature sensor inside the elastomeric article itself, and placing a pressure sensor inside the vulcanization chamber;
During the heating process, the temperature inside the elastomer article and the pressure of the mixed fluid are measured, and the pressure and temperature of the mixed fluid are adjusted by a controller to match preset pressure and temperature conditions, and vulcanization is performed. Exists.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is an explanatory diagram of the vulcanization method of the present invention, in which a tire A is used as an example of the vulcanizable elastomer article, and in the drawing, the elastomer article is inserted into the vulcanization chamber, that is, the mold, through the vulcanization bag. This shows the state in which the vulcanization of the tire A loaded in the vehicle has progressed considerably.

In FIG. 1, 1 is a mold consisting of an upper mold 2 and a lower mold 3, and 4 is a vulcanizing bag, which expands when fluid is supplied, and a tire is placed between the vulcanizing bag 4 and the mold 1. A is involved. 5 is a pressure sensor placed inside the vulcanization chamber, 6 is the tip of tire A
The mixed fluid is vulcanized by a temperature sensor (for example, a thermocouple) placed on the mold 1 so as to reach a desired location, and a controller 7 connected to a pressure sensor 5, a temperature sensor 6, and an automatic control valve described below. It functions to constantly adjust and maintain optimal pressure and temperature conditions. 8 is a check valve, V
,,V2. V3 is an automatic control valve provided in each of the pipes for steam S1, inert gas G1, and exhaust gas E. The pressure and temperature conditions suitable for tire vulcanization are set in advance in the controller 7, and the signals of the pressure inside the vulcanization chamber and the temperature inside the tire A itself are transmitted from the sensors 5 and 6. - When the steam is output to the roller rough, the commie roller 7 automatically operates each automatic control valve so that the mixed fluid with the pressure and temperature matching the above setting conditions can be sent into the vulcanization chamber. or inert gas, or exhaust the mixed fluid.

Incidentally, a plurality of pressure sensors and temperature sensors may each be arranged. For example, as shown in FIG. 2, the temperature sensor can measure the temperature of each of the P, Q, R, and S portions of the tire A.

The temperature sensor 6 has a length of 1 to 5 m, as shown in Figure 3.
It is a needle-shaped thermocouple, which is rigidly held in a NAND-shaped support tube 9, and whose rear end is connected to a lead wire 10, and which is connected to the mold 1.
A support tube 9 is inserted into a large diameter 1iffi hole 11 drilled at a desired location.
It is attached by screwing it on. The lead wire is passed through the small diameter through hole 12. The sensor 6 may be made retractable into the tire by an air cylinder (not shown) provided inside the mold instead of the above-mentioned fixed type.

Example 1 This will be explained in more detail, for example, in the case where a tire of 1000 to 20 size is used as the article to be vulcanized.

The vulcanization conditions for tire vulcanization of sizes 1000 to 20 are a temperature of 140 to 200°C and a pressure of 15 to 30 kg/cJ, for example, 25 kg/cn at 150°C! The following conditions are set in advance in the controller 7. First, a green tire is loaded into a mold, and steam and inert gas are directly supplied into the vulcanization chamber under the control of the controller 7 to form a mixed fluid.

This starts vulcanization. During the heating process using the mixed fluid, signals of the pressure inside the mixed fluid (in the vulcanization chamber) and the temperature inside the tire A (shoulder P) are input to the controller 7, and the temperature is set at a preset temperature of 150°C and 25kg/c+A. Automatically adjusts steam, inert gas, and mixed fluid automatic regulating valves v, , VZ V3 [J close] according to each condition.

For example, if we talk about control when the pressure or temperature of a mixed fluid is too high or too low, if only the temperature is below the set value, V + , V z and V3 are opened, and if the pressure is too high above the set value and the temperature If it is insufficient than the set value, first open (3) to exhaust the mixed fluid, then open (1) to inject steam.

If only the pressure is insufficient than the set value, V2 may be opened while V and V3 are closed to supply inert gas into the vulcanization chamber.

In this manner, the tire vulcanization (heating process) is completed by supplying the mixed fluid under the above conditions for 40 to 50 minutes. The same applies to the case where vulcanization is performed without passing through a vulcanization bag.

Case 2 In another embodiment, instead of setting one specific temperature value (for example 150° C. in the above case) in the controller 7 as the temperature condition, a temperature value as a function of time may be set. In this case, the pressure condition is constant (for example, 25 kg/c
J).

There are two ways to set the temperature value as a function of time:

The first method is to place the altitude sensor 6 at a specific part of the tire A, for example, the part P where vulcanization is delayed the most (Fig. 2), and to approximate the time-temperature curve of the specific part as shown below. The temperature is controlled by setting a temperature value in the controller 7 (FIG. 4).

Vulcanization time Set temperature 0 to 3 minutes 80°C 3 to 10 minutes 130°C 10 to 30 minutes 150°C Part 2 differs from case part 1 above only in the following points. That is, the temperature is controlled by setting a temperature value expressed by a linear equation or an equation of higher order that matches the time-temperature curve itself of a desired specific part at each time within a certain range as shown below. Yes (Figure 5).

Vulcanization time Set temperature 0-10 minutes Temperature - α1 x Time + β210-30 minutes
Temperature - α2 x time → -β2 (α1.α2 is the slope of the straight line, β2 is the intercept) Case 36 Multiple placement inside the tire (Fig. 2 P, Q).

In response to the temperature signal at point P, any one of the temperature sensors R, S) L, etc. performs the temperature control (main control) of Example 2 above, and on the other hand, The upper limit temperature value (e.g. 200°C) or the lower limit temperature value (e.g. 100°C) of tire A is set in advance in the chondro rough, and the sensor showing the highest value among the plurality of temperature sensors (e.g. Q in Fig. 2) is set in advance. When the temperature signal at the point) exceeds the above-mentioned two-limit temperature value, the automatic steam control valve V1 is closed to prevent the temperature from decreasing further, and the sensor indicating the lowest value (for example, the When the temperature signal at point P in Figure 2 is below the lower limit temperature value, the temperature is controlled by opening the steam automatic control valve ■1 to prevent the temperature from dropping below that value.
sub-control). In this method, the control system automatically shifts from main control to sub-control control in accordance with the temperature signal of each part.

Example 4: The temperature condition set in the controller is one temperature value,
The pressure condition is to control the temperature inside the tire and the pressure of the mixed fluid by setting a plurality of pressure values as a function of time, that is, pressure values that approximate the time-pressure curve as shown below. Figure 6).

Vulcanization time Set pressure value 0 to 3 minutes 10 kir/cJ 3 to 10 minutes 20 kg/cJ 10 to 30 minutes 25 kg/c+a Example 5 The temperature conditions set in the controller are multiple temperature values as a function of time, and The pressure conditions set a plurality of pressure values as a function of time to control the temperature within the tire and the pressure of the mixed fluid. In this case, there are 12 iffi methods, and one is to make the pressure setting value the same as in case 4, and the temperature setting value to be the same as the temperature value that approximates the time-temperature curve in part 1 of case 2. In case 2, the pressure setting value is the same as in case 4, and the temperature setting value is the same as the temperature value expressed by a linear equation or higher order that matches the time-temperature curve itself in part 2 of case 2. .

Case 6 The pressure conditions set in the controller are the same as in Case 4 to perform pressure control, and the temperature conditions are set to multiple temperature values as a function of time, that is, the same as the first or second temperature value of Case 2, Furthermore, the upper limit temperature value of tire A (for example, 200
℃) and a lower limit temperature value (for example lOOoC) are set in the controller, and if the temperature signal of the sensor that indicates the highest value among multiple temperature sensors exceeds the upper limit temperature value, the steam is The automatic control valve V is closed, and when the temperature signal from the sensor indicating the lowest value is less than the lower limit temperature value, the temperature is controlled so as not to fall below that value.

In the method of the present invention, after the vulcanization process, the entire vulcanization process is completed through conventionally known steps such as a cooling water process.

In addition to the tires described in the examples, examples of elastomer articles employing the vulcanization method of the present invention include fenders, sleeves, hoses, and the like.

(Effects of the Invention) As described above, in the method of the present invention, the temperature sensor is placed inside the elastomer article itself to directly control the temperature of the elastomer article. It is possible to more effectively prevent vulcanization, improve the appropriate degree of vulcanization, and further improve the efficiency of energy consumption such as steam.

Furthermore, more accurate vulcanization control can be achieved by controlling the temperature or pressure of specific parts of the elastomer article based on the time-temperature curve; Alternatively, by controlling the upper limit temperature value or the lower limit temperature value in addition to pressure control, the entire article to be vulcanized can be kept within a desired range of proper vulcanization.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view of the vulcanizing device used to carry out the vulcanization method of the present invention, Fig. 2 is an explanatory diagram showing the temperature measurement points inside the tire by a temperature sensor, and Fig. 3 is a longitudinal cross-sectional view of the vulcanizing device used to carry out the vulcanization method of the present invention. Figures 4 and 5 are graphs of the time-temperature curve of tire vulcanization, and are explanatory diagrams showing the temperature value (set value) as a function of time. FIG. 2 is an explanatory diagram showing a pressure value (set value) as a function of time in a graph of a time-pressure curve of tire vulcanization. 1... Mold, 4... Vulcanizing bag, 5... Pressure sensor, 6... Temperature sensor, 7...
Controller 1-Roller, 9...Temperature sensor support tube, 10
...Large diameter through hole. Patent Applicant Sumitomo Rubber Industries Co., Ltd. Procedures + 'rtt Seika) December 1985 - ζ Date Patent Application No. 206700υ 1982 2. Name of the invention Power of elastomer article ■ Sulfur method 3. Amendment person case and Relationship Patent applicant address 1-1-1 Tsutsui-cho, Chuo-ku, Kobe City Temperature - α
1 x time + β 2 pieces says "0 to 10 minutes temperature - α, X
time→−β1”. The statement in the first line of page 11 of the specification says, ``(Also, α1°α2 is the slope of the straight line, β2 is the intercept), 1 [(Also, α1.
α2 is the slope of the straight line, β1. β2 is section)-1, one mouse is dissected. (2) Correct the attached sheet 1l11 in Figure 5. that's all

Claims (7)

[Claims] (1) A method of vulcanizing an elastomer article placed in a vulcanization chamber using a mixed fluid obtained by directly mixing a low heat capacity gas and a high heat capacity thermal fluid in the vulcanization chamber, the method comprising: to set the desired pressure and temperature conditions and place a temperature sensor inside the elastomer article itself and a pressure sensor inside the vulcanization chamber to maintain the temperature inside the elastomer article and the pressure of the mixed fluid throughout the heating process. Measure and
A method for vulcanizing an elastomer article, characterized in that vulcanization is performed by adjusting the pressure and temperature of the mixed fluid using a controller so as to match preset pressure and temperature conditions. (2) The pressure and temperature conditions set in the controller are 1.
2. A method of vulcanizing an elastomeric article according to claim 1, wherein the vulcanization method is: 1 pressure value and 1 temperature value. (3) A patent claim in which the pressure condition set in the controller is one pressure value, and the temperature condition is a plurality of temperature values as a function of time based on a time-temperature curve at a specific location within the elastomer article. A method for vulcanizing an elastomer article according to item 1. (4) The pressure condition set in the controller is one pressure value, and the temperature condition is a plurality of temperature values as a function of time based on the time-temperature curve of a specific part within the elastomer article, as well as the upper limit of the elastomer article. A method for vulcanizing an elastomer article according to claim 1, wherein the temperature value or the lower limit temperature value is used. (5) The method of vulcanizing an elastomer article according to claim 1, wherein the pressure condition set in the controller is a plurality of pressure values as a function of time, and the temperature condition is a single temperature value. (6) The pressure condition set in the controller is a plurality of pressure values as a function of time, and the temperature condition is a plurality of temperature values as a function of time. Sulfur method. (7) The pressure conditions set in the controller are a plurality of pressure values as a function of time, and the temperature conditions are a plurality of temperature values as a function of time and an upper limit temperature value or a lower limit temperature value of the elastomer article. A method for vulcanizing an elastomer article according to claim 1.