JP3367896B2 - Belt forming method and belt forming apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt molding method and a belt molding apparatus, such as a timing belt, a profile belt, a ribbed belt, and a flat belt, which are formed of polyurethane or the like.

[0002]

2. Description of the Related Art In molding an annular belt made of a resin such as polyurethane, a molding comprising an outer mold and an inner mold, as provided in Japanese Patent Publication No. 47-32824 and Japanese Patent Publication No. 2-29006. Molding is performed using a device. That is, the raw resin solution is injected from the injection port provided in the outer mold into the molding cavity formed as a cylindrical cavity between the inner peripheral surface of the outer mold and the outer peripheral surface of the inner mold, After the filled raw material resin liquid is cured and molded, the outer mold and the inner mold are separated and released from the mold to obtain a belt molded in an annular shape.

However, in the method of injecting the raw material resin liquid into the molding cavity from the thin injection port as described above, it is necessary to inject the raw material resin liquid while pressurizing the raw material resin liquid. At this time, air is entrained in the raw material resin liquid. There is a risk. Also, since the injection port is usually provided at one place, the liquid level of the raw material resin liquid injected from the injection port into the molding cavity rises in a state where the vicinity of the injection port is high and the position far from the injection port is low, When the liquid surface of the resin liquid reaches the upper end of the molding cavity,
Air may be entrained in the raw material resin liquid at a place where the liquid level is lower than the inlet. This remarkably occurs when the viscosity of the raw material resin liquid is high and the flow in the molding cavity is poor. Then, when air is entrained in the raw material resin liquid in this way, a belt in which air bubbles are mixed is formed, and there is a problem that a defective occurrence rate due to air bubbles increases.

Therefore, the following molding method has been proposed by the present applicant. That is, the raw material resin liquid is supplied to the bottom portion of the outer die whose upper surface is open, and while the inner die is being inserted into the outer die, the raw material resin liquid is fed between the lower end portion of the inner die and the bottom portion of the outer die. By pressing, the inner mold is inserted into the outer mold to push up and fill the raw material resin liquid into the molding cavity formed between the inner peripheral surface of the outer mold and the outer peripheral surface of the inner mold. In this method, the raw material resin liquid is cured by advancing a crosslinking reaction of the raw material resin liquid in the cavity, and then the raw material resin liquid is cured in the molding cavity to form the belt.

According to this method, since it is not necessary to inject the raw material resin liquid while pressurizing it through the inlet, there is no problem that air is caught when the raw material resin liquid is injected, and the raw material resin liquid is molded. Since the resin is filled while being pushed up into the cavity, the height of the liquid surface of the raw resin liquid in the molding cavity is uniform, and air is trapped in the raw resin liquid at the low liquid level. It also disappears.

As described above, although it is possible to prevent air from being entrained in the raw material resin liquid, when the raw material resin liquid is filled into the molding cavity while being pushed up, the raw material resin liquid is mixed with the air existing in the molding cavity. Since the air is pushed up while coming into contact with the air, bubbles may be mixed in the raw material resin liquid by this air.

Therefore, after the air inside the molding cavity is discharged to reduce the pressure inside the molding cavity, or while the pressure is being reduced, the inner mold is inserted into the outer mold and the raw resin solution is pushed up and filled into the molding cavity. Is being considered.

However, when the air inside the molding cavity is depressurized by discharging the air as described above, the air inside the molding cavity will not be mixed with the raw material resin liquid. When molding is performed by using air bubbles, bubbles are generated from the volatile components contained in the raw material resin liquid, or bubbles are generated from the water remaining in the core wire set in the molding cavity to reinforce the belt. There is a risk of Then, if the raw material resin liquid is hardened and solidified before the bubbles generated in this way come out of the raw material resin liquid, the bubbles will remain in the molded belt, which may cause a defect due to the bubbles. .

Further, as described above, by inserting the inner mold into the outer mold, the raw material resin liquid is filled in the molding cavity formed between the inner peripheral surface of the outer mold and the outer peripheral surface of the inner mold, When the crosslinking reaction of the raw material resin proceeds in the molding cavity to cure it, when the temperature of the inner die is largely deprived of by the raw material resin liquid and the temperature of the inner die drops significantly, the inner die shrinks and the diameter decreases, The space between the inner peripheral surface of the outer mold and the outer peripheral surface of the inner mold widens, and the volume of the molding cavity increases. At this time, if the cross-linking speed of the raw material resin is high, the viscosity of the raw material resin liquid becomes too high at an early point, and it is not possible to follow this volume expansion, and a sink mark is generated inside. There is a problem that cracks may occur inside the solidified molded product, and defective molding tends to occur due to the cracks. Then, in order to prevent the occurrence of molding defects due to such cracks, it is necessary to use a raw material resin liquid that follows the volume change of the molding cavity, that is, a raw material resin liquid with a slow crosslinking rate, As a result, the time becomes longer, the molding cycle becomes longer, and the productivity is reduced.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a belt forming method and a forming apparatus capable of forming a belt having no bubbles. In addition, it is an object of the present invention to provide a belt molding method and a molding apparatus capable of molding a belt having no molding failure due to cracks with high productivity.

[0011]

In the belt molding method according to the present invention, the inner mold 2 is inserted into the outer mold 1 to form an inner peripheral surface of the outer mold 1 and an outer peripheral surface of the inner mold 2. The material resin liquid 4 between the outer mold 1 and the inner mold 2 is pushed up and filled in a molding cavity 3 formed as a cavity between them, and then the material resin liquid 4 is cured in the molding cavity 3 to form an annular belt. In molding, the gas between the outer mold 1 and the inner mold 2 is discharged to reduce the pressure in the molding cavity 3 and the inner mold 2 is inserted into the outer mold 1 to feed the raw resin solution 4 into the molding cavity 3. It is characterized in that it is pushed up and filled, and the reduced pressure is released immediately before the completion of the filling or at the same time as the completion of the filling.

According to a second aspect of the present invention, in the above belt molding method, the degree of vacuum in the molding cavity 3 is 5 mmH.
It is characterized in that the pressure is reduced to g or less.

According to a third aspect of the present invention, in the above belt molding method, the filling detection means detects the filling completion of the raw resin liquid 4 into the molding cavity 3 or the completion of the filling, and based on the detection by the filling detection means. It is characterized in that the reduced pressure is released by means of the above.

According to a fourth aspect of the present invention, in the above-described belt molding method, the filling detection means is formed by using the limit switch 6, and the inner mold 2 is inserted into the outer mold 1 to insert the inner mold 2 into the molding cavity 3. The limit switch 6 detects the relative positional relationship between the outer mold 1 and the inner mold 2 immediately before the completion of the filling of the raw material resin liquid 4 or when the filling of the raw material resin liquid 4 is completed. It is characterized in that immediately before the completion of the filling of No. 4 or the completion of the filling is detected.

According to a fifth aspect of the present invention, in the above belt molding method, the outer mold 1 is formed at the start of the crosslinking of the raw material resin liquid 4.
One of the inner mold 2 and the inner mold 2 is set to a temperature at which the raw material resin liquid 4 is crosslinked, and the other mold temperature of the outer mold 1 and the inner mold 2 is set to a temperature lower than that. The mold is characterized in that the mold set to a low temperature at the start of crosslinking is heated so that the temperatures of the outer mold 1 and the inner mold 2 become substantially equal.

According to a sixth aspect of the present invention, in the above belt molding method, the outer mold 1 is provided at the start of crosslinking of the raw material resin liquid 4.
Is set to a temperature at which the raw material resin liquid 4 is crosslinked, the temperature of the inner mold 2 is set to a temperature lower than the temperature of the outer mold 1, and the temperature of the inner mold 2 is equal to the temperature of the outer mold 1 at the end of the crosslinking. It is characterized in that the inner mold 2 is heated so as to be substantially equal.

According to a seventh aspect of the present invention, in the above belt molding method, the temperature of the inner mold 2 is set to a temperature lower than the temperature of the outer mold 1 by cooling the inner mold 2 after the completion of crosslinking. It is a feature.

According to the eighth aspect of the present invention, in the above belt molding method, the inner mold 2 is heated by passing a heat medium selected from hot water, oil, and steam through the inner mold 2, and the inner mold 2 is heated. It is characterized in that the inner mold 2 is cooled by passing a coolant such as cooling water.

Further, the invention of claim 9 is characterized in that, in the above-mentioned belt molding method, the inner mold 2 is cooled by air-cooling the surface of the inner mold 2.

A belt molding apparatus according to a tenth aspect of the present invention is formed by including an outer mold 1 and an inner mold 2. When the inner mold 2 is inserted into the outer mold 1, the outer mold 1 is formed. Inside of the molding cavity 3 is pushed up and filled into the molding cavity 3 formed as a cavity between the inner peripheral surface of the inner mold 2 and the outer peripheral surface of the inner mold 2. In the molding apparatus for curing the raw material resin liquid 4 to mold the annular belt, the exhaust means for discharging the gas between the outer mold 1 and the inner mold 2 to reduce the pressure in the molding cavity 3; It is characterized by comprising a filling detection means for detecting the completion of the filling of the raw material resin liquid 4 or the completion of the filling, and a control means for releasing the pressure reduction by the exhaust means based on the detection by the filling detection means. .

A belt forming apparatus according to an eleventh aspect of the present invention is formed by including an outer mold 1 and an inner mold 2. When the inner mold 2 is inserted into the outer mold 1, the outer mold 1 is formed. Inside of the molding cavity 3 is pushed up and filled into the molding cavity 3 formed as a cavity between the inner peripheral surface of the inner mold 2 and the outer peripheral surface of the inner mold 2. In the molding apparatus for curing the raw material resin liquid 4 to mold the annular belt, the outer mold 1 is provided with the exhaust port 9 for discharging the gas between the outer mold 1 and the inner mold 2 to reduce the pressure in the molding cavity 3. A flange 10 that closes the communication between the exhaust port 9 and the molding cavity 3 when the inner mold 2 is inserted into the outer mold 1 immediately before the completion of the filling of the raw resin solution 4 into the molding cavity 3 or until the completion of the filling. It is characterized by being provided in the inner mold.

According to a twelfth aspect of the present invention, in the above belt forming apparatus, an outer die heating means for heating the outer die 1,
Inner mold heating means for heating the inner mold 2, inner mold cooling means for cooling the inner mold 2, and so that the temperature of the outer mold 1 becomes the temperature at which the raw material resin liquid 4 is crosslinked at the start of the crosslinking of the raw material resin liquid 4. The outer die 1 is heated by the outer die heating means, and the inner die 2 is cooled by the inner die cooling means so that the temperature of the inner die 2 becomes lower than the temperature of the outer die 1. The inner mold 2 is heated by the inner mold heating means so that the temperature of 2 becomes substantially equal to that of the outer mold 1.
It is characterized by comprising temperature control means for respectively controlling the outer die heating means, the inner die heating means, and the inner die cooling means so as to heat the.

According to a thirteenth aspect of the present invention, in the above belt forming apparatus, the outer die heating means is formed by providing a heat medium passage 50 for passing a heat medium provided in the outer die 1, Heat medium passage 5 for passing the heat medium provided in the inner mold 2 through the mold heating means.
It is characterized by being formed by including 1.

According to a fourteenth aspect of the present invention, in the above belt forming apparatus, the inner die cooling means is formed by including a refrigerant passage 52 provided in the inner die 2 for passing a refrigerant. It is a feature.

According to a fifteenth aspect of the present invention, in the above belt forming apparatus, the inner die cooling means is formed by an air blower 53 for blowing air onto the surface of the inner die 2 to cool it. It is a thing.

According to a sixteenth aspect of the present invention, in the above belt forming apparatus, the heat medium passage 50 provided in the outer mold 1 is provided.
And a heat medium supply device 5 for supplying a heat medium to the heat medium passage 50.
4 together with the outer die heating means, the inner die heating means is formed by the heat medium passage 51 provided in the inner die 2 and the heat medium supply device 54 for supplying the heat medium to the heat medium passage 51. The heater 55 for heating the heat medium formed in the heat medium supply device 54 and the pump 56 for feeding the heat medium are controlled by the temperature control means.

According to a seventeenth aspect of the present invention, in the above belt forming apparatus, the heat medium flow passage 50 provided in the outer mold 1 is provided.
And a steam supply device 57 for supplying steam to the heat medium flow path 50 form an outer die heating means, and a heat medium flow path 51 provided in the inner mold 2 and steam in the heat medium flow path 51. The inner mold heating means is formed together with the steam supply device 57 for supplying heat to the heat medium flow passage 50 of the outer mold 1 and the heat medium flow passage 51 of the inner mold 2 to control the amount and pressure of the steam. It is characterized in that the temperature is controlled by a temperature control means.

According to the eighteenth aspect of the present invention, in the above belt forming apparatus, the refrigerant flow passage 52 provided in the inner mold 1 is provided.
And a refrigerant supply device 5 for supplying a refrigerant to the refrigerant channel 52
8 forms an internal cooling means, a cooling device 59 for cooling the refrigerant provided in the refrigerant supply device 58, and a pump 6 for sending the refrigerant.
0 is controlled by the temperature control means based on the temperature of the inner mold 2 measured by the temperature sensor 61.

According to a nineteenth aspect of the present invention, in the above belt forming apparatus, a non-contact type thermometer 62 for measuring the temperature in a non-contact manner is used as the temperature sensor 61.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, claims 1 to 4 and claim 1
An embodiment of the invention of No. 0 will be described.

FIGS. 1 to 3 show an example of a molding apparatus, and the outer mold 1 and the inner mold 2 form a molding device. The outer mold 1 is a molding recess 3 having a circular opening on the upper surface.
9 is provided, and a decompression chamber 40 that opens inward is formed in the upper part of the molding recess 39 over the entire circumference.
The outer mold 1 is attached to the lower platen 19 of the mold clamping press. The outer mold 1 is formed with an exhaust port 9 that opens to the upper surface of the outer mold 1 and the decompression chamber 40.
An evacuation device 34 such as a vacuum pump is connected through 3. The exhaust port 9, the exhaust hose 33, and the exhaust device 34 form an exhaust unit.

Further, the inner mold 2 is formed in a columnar shape, and is formed by a flange 10 having a circular plane shape protruding over the entire outer circumference of the upper end portion of the core portion 42. The outer diameter radius of the core portion 42 is formed to be smaller than the inner diameter radius of the molding recess 39 of the outer mold 1 by the thickness dimension of the belt to be molded, and the molding recess 39 of the outer mold 1 is formed. When the core portion 42 of the inner mold 2 is inserted into the inner mold 2, a molding cavity 3 for forming a belt is formed between the inner peripheral surface of the molding recess 39 and the outer peripheral surface of the core portion 42. is there. When molding a toothed belt such as a timing belt,
The outer peripheral surface of the core portion 42 is provided with a large number of parallel grooves along its axial direction. Also the flange 10
Has an outer diameter equal to the inner diameter of the opening on the upper surface of the upper mold 1 of the molding recess 39.

In molding the belt with the molding apparatus formed as described above, first, with the outer mold 1 and the inner mold 2 separated from each other, the raw resin solution 4 such as polyurethane is placed on the bottom of the outer mold 1. Supply. Next, the outer mold 1 is raised with the inner mold 2 fixed, and the core portion 42 of the inner mold 2 is inserted into the molding recess 39 of the outer mold 1. Then, as shown in FIG. 2, when the flange portion 10 of the inner mold 2 is inserted into the opening of the upper surface of the molding recess 39, the inner peripheral surface of the molding recess 39 and the core portion 42 of the inner mold 2 are inserted.
Since the inside of the cavity between the outer peripheral surface and the outer peripheral surface of the inner mold is sealed by the flange 10, the exhaust device 34 is actuated from this point and the space between the molding recess 39 of the outer mold 1 and the core 42 of the inner mold 2 is activated. Air of the outer mold 1 is discharged from the exhaust port 9 through the decompression chamber 40.
The cavity between the molding recess 39 and the core 42 of the inner mold 2 is decompressed. At this point, the lower end of the core portion 42 of the inner mold 2 has not reached the raw material resin liquid 4 supplied to the bottom of the outer mold 1. In addition, by depressurizing the cavity between the molding recess 39 of the outer mold 1 and the core portion 42 of the inner mold 2 in this way, bubbles inside the raw material resin liquid 4 and the molding recess of the outer mold 1 are reduced. Water is removed from the inside of the reinforcing core wire, which is arranged as necessary on the inner circumference of 39 and the outer circumference of the core portion 42 of the inner mold 2.

Next, when the outer die 1 is further raised and the core portion 42 of the inner die 2 is deeply inserted into the molding recess 39, the lower end portion of the core portion 42 of the inner die 2 is the raw material of the bottom portion of the outer die 1. It reaches the resin liquid 4 and is pushed between the lower surface of the core portion 42 and the bottom surface of the outer mold 1. The raw material resin liquid 4 thus pushed is pushed up in the cavity between the inner peripheral surface of the molding recess 39 of the outer die 1 and the outer peripheral surface of the core portion 42 of the inner die 2, as shown in FIG. . Then, the outer mold 1 is further raised to completely insert the core portion 42 of the inner mold 2 into the molding recess 39, so that FIG.
In the molding cavity 3 formed between the inner peripheral surface of the molding recess 39 of the outer mold 1 and the outer peripheral surface of the core portion 42 of the inner mold 2 as described above, between the molding recess 39 and the core portion 42. Is filled with the raw material resin liquid 4 that is pushed up. In this way, when pushing up and filling the raw material resin liquid 4 into the molding cavity 3,
Since the inside of the molding cavity 3 is depressurized, it is possible to prevent the air inside the molding cavity 3 from being mixed into the raw material resin liquid 4.

At this time, immediately before the completion of the filling of the raw resin liquid 4 into the molding cavity 3 or at the same time as the completion of the filling, the operation of the exhaust device 34 is stopped to release the decompression, and the inside of the molding cavity 3 is brought to the atmospheric pressure. I'm trying to put it back. By releasing the reduced pressure in the molding cavity 3 and returning it to the atmospheric pressure in this way, bubbles are generated from volatile components such as water contained in the raw material resin liquid 4 or remain in the reinforcing core wire. It is possible to prevent bubbles from being generated from the water contained therein.

A limit switch 6 is provided as a filling detection means for detecting the completion of filling the raw resin solution 4 into the molding cavity 3 or the completion of filling. The limit switch 6 is attached to the frame body 35 which is fixed together with the inner mold 2. Then, the outer mold 1 is raised so that the core portion 4 of the inner mold 2 is placed in the molding recess 39 of the outer mold 1.
2 is inserted, and when the outer mold 1 is raised until just before the core part 42 is completely inserted into the molding recess 39, the actuator 36 of the limit switch 6 is provided with a flange provided on the outer periphery of the lower end part of the outer mold 1. By setting the mounting position of the limit switch 6 in advance so that 37 contacts, it is possible to detect the completion of the filling of the raw resin solution 4 into the molding cavity 3 by the ON operation of the limit switch 6. is there. In addition, the outer mold 1 is lifted to form the molding recess 3 of the outer mold 1.
The core part 42 of the inner mold 2 is inserted into the inside 9 to form the molding recess 39.
When the outer mold 1 is raised until the core part 42 is completely inserted therein, the actuator 36 of the limit switch 6 is brought into contact with the flange 37 provided on the outer periphery of the lower end part of the outer mold 1 in advance. By setting the mounting position of, the completion of the filling of the raw resin solution 4 into the molding cavity 3 can be detected by the ON operation of the limit switch 6.

The filling detection means formed by the limit switch 6 is connected to the control means formed by a CPU or a relay, and the control means is shown in FIG. 4 in the exhaust device 34 forming the exhaust means. Are connected. Then, the raw material resin liquid 4 to the molding cavity 3 by the filling detection means
Immediately before the completion of filling or when the completion of filling is detected, this detection signal is input to the control means, and the control means operates based on this detection signal to stop the operation of the exhaust device 34 forming the exhaust means, and the exhaust device The pressure reduction by 34 is released so that the inside of the molding cavity 3 returns to the atmospheric pressure. In this way, by controlling the exhaust device 34 of the exhaust means using the filling detection means and the control means, the molding cavity 3
Immediately before or when the filling of the raw material resin liquid 4 into the resin is completed, the depressurization can be automatically released, which facilitates the automation of molding. In the embodiment of FIGS. 1 to 3, the position of the outer mold 1 with respect to the inner mold 2 is detected by the limit switch 6 to detect the completion of the filling of the raw resin solution 4 into the molding cavity 3 or the completion of the filling. However, when the outer die 1 is fixed and the inner die 2 is moved downward so that the core portion 42 of the inner die 2 is inserted into the molding recess 39 of the outer die 1, Inner mold 2
Is detected by the limit switch 6 to detect the completion of the filling of the raw resin solution 4 into the molding cavity 3 or the completion of the filling.

After the raw resin solution 4 is filled in the molding cavity 3 as described above, the raw resin solution 4 is cured in the molding cavity 3 to perform molding. Here, since the bubbles are not generated in the raw material resin liquid 4 by releasing the reduced pressure in the molding cavity 3 as described above, it is possible to obtain a molded product having no bubbles. After the molding is completed in this manner, the molded product is taken out, the molded product is taken out, and if necessary, the molded product is sliced to obtain an annular belt.

Next, examples and comparative examples of the above embodiment will be shown.

(Example 1) As the raw material resin liquid 4, a polyether type urethane prepolymer and 3,3 'as a curing agent were used.
-Using a mixture of dicyclo-4,4'-diaminodiphenylmethane and a plasticizer of 20 phr, first, with the outer mold 1 and the inner mold 2 separated from each other, a polyester core wire is provided on the outer periphery of the core 42 of the inner mold 2. 2 and the raw material resin liquid 4 is supplied to the bottom of the molding recess 39 of the outer mold 1 as shown in FIG.
As shown in FIG.
Was inserted to seal the hollow portion between the molding recess 39 and the core portion 42, and the hollow portion was depressurized to a vacuum degree of 1 mmHg by absolute pressure. After the raw resin solution 4 is degassed by holding for 50 seconds, the outer mold 1 is raised at a constant speed to insert the core portion 42 of the inner mold 2 into the molding recess 39 of the outer mold 1. Like the inner peripheral surface of the molding recess 39 of the outer mold 1 and the core portion 42 of the inner mold 2
Immediately before the raw resin solution 4 was filled into the molding cavity 3 formed between the outer peripheral surfaces of the outer mold 1, the rising speed of the outer mold 1 was reduced. Then, at the same time as the filling of the raw material resin liquid 4 into the molding cavity 3 was completed, the depressurization was released and the inside of the molding cavity 3 was returned to the atmospheric pressure. In this state, molding is performed by curing the raw material resin liquid 4 in the molding cavity 3, and the outer mold 1 and the inner mold 2 are separated into upper and lower parts and released from the mold, thereby having 150 trapezoidal teeth at a pitch of 5 mm. An annular toothed belt molding was obtained.

(Comparative Example 1) An annular toothed belt molded article was obtained in the same manner as in Example 1 except that the decompression was set to a vacuum degree of 7 mmHg in absolute pressure.

(Comparative Example 2) Reduced pressure is 14 mmHg in absolute pressure.
An annular toothed belt molded article was obtained in the same manner as in Example 1 except that the degree of vacuum was set.

With respect to the toothed belt molded products obtained in Example 1 and Comparative Examples 1 and 2, the number of bubbles was measured. as a result,
No bubbles were present in Example 1. On the other hand, in Comparative Example 1, many bubbles having a diameter of 0.5 mm were present, and in Comparative Example 2, many bubbles having a diameter of 1 mm were present.

As described above, when the pressure of the molding cavity 3 is reduced to 7 mmHg or 14 mmHg, it is impossible to completely prevent the bubbles from remaining. Therefore, as in the invention of claim 2, the pressure reduction in the molding cavity 3 is 5 mmHg.
It is preferable to carry out at a vacuum degree of It is preferable that the degree of pressure reduction in the molding cavity 3 is as low as possible. Therefore, the lower limit of the degree of pressure reduction in the molding cavity 3 is 0 m of absolute vacuum.
It is mHg.

[0045]

[Table 1] Next, an embodiment of the invention of claim 11 will be described.

FIG. 5 to FIG. 7 show an example of the molding apparatus, and the outer mold 1 and the inner mold 2 form the molding device. The outer mold 1 is formed to have substantially the same shape as that shown in FIG. 1 to FIG. 3, but the inside of the decompression chamber 40 is formed in the upper part of the molding recess 39 by opening inward over the entire circumference. A concave step portion 41 is formed along the entire circumference at the lower edge of the circumference. The inner diameter of the concave step portion 41 is formed to be equal to the inner diameter of the opening on the upper surface of the molding recess 39. Further, the inner mold 2 is also shown in FIGS.
Although the flange 10 is formed to have substantially the same shape as that of the above, the thickness (height) dimension of the flange 10 provided over the entire outer circumference of the upper end portion of the core portion 42 is larger than that described above. is there.

In molding the belt with the molding apparatus formed as described above, first, with the outer mold 1 and the inner mold 2 separated from each other, a raw material resin liquid 4 such as polyurethane is applied to the bottom of the outer mold 1. Supply. Next, the outer mold 1 is raised with the inner mold 2 fixed, and the core portion 42 of the inner mold 2 is inserted into the molding recess 39 of the outer mold 1. Then, as shown in FIG. 5, when the flange portion 10 of the inner mold 2 is inserted into the opening of the upper surface of the molding recess 39, the inner peripheral surface of the molding recess 39 and the core portion 42 of the inner mold 2 are inserted.
Since the inside of the cavity between the outer peripheral surface of the mold and the outer peripheral surface of the inner mold is sealed by the flange 10, the exhaust device is operated from this point and the space between the molding recess 39 of the outer mold 1 and the core part 42 of the inner mold 2 is activated. Air is discharged from the exhaust port 9 through the decompression chamber 40 to decompress the cavity between the molding recess 39 of the outer mold 1 and the core 42 of the inner mold 2. At this point, the lower end of the core portion 42 of the inner mold 2 is the outer mold 1
Has not reached the raw material resin liquid 4 supplied to the bottom of the. In addition, by depressurizing the cavity between the molding recess 39 of the outer mold 1 and the core portion 42 of the inner mold 2 in this way, bubbles inside the raw material resin liquid 4 and the molding recess of the outer mold 1 are reduced. Water is removed from the inside of the reinforcing core wire, which is arranged as necessary on the inner circumference of 39 and the outer circumference of the core portion 42 of the inner mold 2.

Next, when the outer die 1 is further raised and the core portion 42 of the inner die 2 is deeply inserted into the molding recess 39, the lower end portion of the core portion 42 of the inner die 2 is the raw material of the bottom portion of the outer die 1. It reaches the resin liquid 4 and is pushed between the lower surface of the core portion 42 and the bottom surface of the outer mold 1. The raw material resin liquid 4 thus pushed is pushed up in the cavity between the inner peripheral surface of the molding recess 39 of the outer die 1 and the outer peripheral surface of the core portion 42 of the inner die 2, as shown in FIG. . Then, the outer mold 1 is further raised to completely insert the core portion 42 of the inner mold 2 into the molding recess 39, so that FIG.
In the molding cavity 3 formed between the inner peripheral surface of the molding recess 39 of the outer mold 1 and the outer peripheral surface of the core portion 42 of the inner mold 2 as described above, between the molding recess 39 and the core portion 42. Is filled with the raw material resin liquid 4 that is pushed up. In this way, when pushing up and filling the raw material resin liquid 4 into the molding cavity 3,
Since the inside of the molding cavity 3 is depressurized, it is possible to prevent the air inside the molding cavity 3 from being mixed into the raw material resin liquid 4.

Here, as shown in FIG. 6, the outer die 1 is raised to raise the inner peripheral surface of the molding recess 39 of the outer die 1 and the core portion 42 of the inner die 2.
Immediately before the completion of the filling of the raw material resin liquid 4 into the molding cavity 3 formed between the outer peripheral surfaces of the inner mold 2, the flange 10 of the inner mold 2 is inserted into the inner circumference of the recessed step portion 41 of the outer mold 1, The inner peripheral opening of the decompression chamber 40 of the outer mold 1 is closed by the flange 10. When the inner peripheral opening of the decompression chamber 40 of the outer mold 1 is closed in this way, the inner peripheral surface of the molding recess 39 of the outer mold 1 and the inner mold 2 are closed.
The communication between the molding cavity 3 between the outer peripheral surface of the core part 42 and the exhaust port 9 is cut off, and the reduced pressure in the molding cavity 3 is released. 6 to 7, when the core portion 42 of the inner mold 2 is inserted deeper into the molding recess 39 of the outer mold 1, the inner peripheral surface of the molding recess 39 of the outer mold 1 and the inner mold 2 are inserted. Since the volume between the outer peripheral surfaces of the core portions 42 becomes small, the inside of the molding cavity 3 is changed from the depressurized state to the atmospheric pressure state and further to the pressurized state. By releasing the reduced pressure in the molding cavity 3 in this way, bubbles are generated from volatile components such as water contained in the raw material resin liquid 4, or bubbles are generated from water remaining in the reinforcing core wire. It is possible to prevent the occurrence of.

After the raw resin solution 4 is filled in the molding cavity 3 as described above, the raw resin solution 4 is cured in the molding cavity 3 to perform molding. Here, since the bubbles are not generated in the raw material resin liquid 4 by releasing the reduced pressure in the molding cavity 3 as described above, it is possible to obtain a molded product having no bubbles. Then, after the molding is completed in this way, the belt can be obtained by demolding, taking out the molded product, and cutting the molded product into slices if necessary.

When the belt is formed while the depressurizing operation is performed as in each of the above-described embodiments, it is preferable that the belt is formed.
In the inventions of 12 and 19 at the same time, the outer mold 1 and the inner mold 2 are simultaneously formed.
Temperature control. Embodiments of the inventions of claims 5 to 9 and 12 to 19 will be described below.

FIG. 8 shows an example of the molding apparatus.
The molding device is formed by an outer mold 1 and an inner mold 2. The outer mold 1 is formed in a cylindrical shape by opening a molding recess 39 on the upper surface, and is attached to the lower plate (not shown) of the mold clamping press. A heat medium channel 50 is provided in the outer mold 1.

The inner mold 2 is formed by projecting a cover plate 63 on the upper surface of a cylindrical core portion 42, and a hollow portion 64 is formed inside the core portion 42. This cavity 6
In FIG. 4, the heat medium flow passage 51 and the coolant flow passage 52 are formed to serve as both. The outer diameter radius of the core portion 42 is formed to be smaller than the inner diameter radius of the molding recess 39 of the outer mold 1 by the thickness dimension of the belt to be molded, and the molding recess 39 of the outer mold 1 is formed. When the core portion 42 of the inner mold 2 is inserted into the inner mold 2, a molding cavity 3 for forming a belt is formed between the inner peripheral surface of the molding recess 39 and the outer peripheral surface of the core portion 42. is there. When a toothed belt such as a timing belt is molded, a core portion 42 having a large number of parallel grooves along its axial direction is used on the outer peripheral surface thereof.

In FIG. 8, reference numeral 54 denotes a heat medium supply device, which is a heat medium tank 65 and a heater 55 in the heat medium tank 65.
And a pump 56. Heat medium tank 65
The heat medium such as hot water and oil is stored in
The heating medium is heated by the heater 55. A delivery path 66 is connected to the upper part of the heat medium tank 65, and the pump 56 is provided in the delivery path 66. The delivery passage 66 is branched into an outer die delivery passage 67 and an inner die delivery passage 68, and the outer die delivery passage 67 is provided below the heat medium passage 50 of the outer die 1 and is provided with the inner die delivery passage. 68 are respectively connected to the lower part of the heat medium flow path 51 of the inner mold 2. An open / close valve 69 is provided in the outer die delivery passage 67, and an open / close valve 70 is provided in the inner die delivery passage 68. A return path 71 is provided below the heat medium tank 65.
Are connected to each other, the return path 71 branches into an outer mold return path 72 and an inner mold return path 73, and the outer mold return path 72 is provided on the upper side of the heat medium flow path 50 of the outer mold 1, The return paths 73 for use are respectively connected to the upper portions of the heat medium flow paths 51 of the inner mold 2. The outer mold return path 72 and the inner mold return path 73 are respectively provided with flow rate adjusting valves 74 and 75 formed of electromagnetic valves or the like, and the flow rate adjusting valves 74 and 75 are electrically connected to a temperature control device 76 described later. And is controlled by the temperature controller 76. The heating medium passage 50 provided in the outer mold 1 and the heating medium supply device 54 that supplies the heating medium to the heating medium flow passage 50 form an outer die heating means. The heat medium flow path 51 provided and the heat medium supply device 54 that supplies the heat medium to the heat medium flow path 51 form an internal heating means.

The heat medium heated in the heat medium tank 65 is the pump 5
6 is sent out through the delivery passage 66, and is also supplied from the delivery passage 66 through the outer die delivery passage 67 to the heat medium flow passage 50 of the outer die 1, and the outer die 1 can be heated by this heat medium. . The heat medium in the heat medium flow path 50 is returned from the outer mold return path 72 to the heat medium tank 65 through the return path 71.
Further, the heat medium passes from the delivery passage 66 through the inner die delivery passage 68,
It is supplied to the heat medium flow path 51 of the inner mold 2, and the inner mold 2 can be heated by this heat medium. The heat medium in the heat medium passage 51 is returned from the inner mold return passage 73 through the return passage 71 to the heat medium tank 65.

In FIG. 8, reference numeral 58 denotes a refrigerant supply device, which is provided with a cooler 59 and a pump 60. The cooler 59 is formed so as to cool a refrigerant such as cold water in a temperature range of 10 to 60 ° C. The cooler 59 is connected with a refrigerant delivery path 77 and a refrigerant return path 78, and the pump 60 Is provided in the refrigerant delivery path 77. The refrigerant delivery passage 77 is connected to the inner die delivery passage 68 through a switching valve 79 formed of a three-way valve, and the refrigerant return passage 78 is connected through a switching valve 80 formed of a three-way valve. Is connected to the inner mold return passage 73, the refrigerant discharge passage 77 is connected to the refrigerant flow passage 52 of the inner mold 2 through the inner mold discharge passage 68, and the refrigerant return passage 78 is connected through the inner mold return passage 73. It is connected to the coolant channel 52 of the mold 2.
The coolant flow channel 52 and the coolant supply device 58 provided in the inner mold 2 form an inner mold cooling means.

The coolant cooled by the cooler 59 is supplied to the pump 6
0 is sent out through the refrigerant delivery passage 77, is supplied from the refrigerant delivery passage 77 through the inner valve delivery passage 68 through the switching valve 79 to the refrigerant passage 52 of the inner die 2, and the inner die 2 is supplied by this refrigerant. Can be cooled. The refrigerant in the refrigerant flow path 52 is returned from the inner mold return passage 73 through the switching valve 80 to the refrigerant return passage 78 to the cooler 59.

Temperature sensors 81 and 61 are embedded in the outer mold 1 and the inner mold 2, respectively, and the temperature of the outer mold 1 and the temperature of the inner mold 2 are measured by the temperature sensors 81 and 61. There is. These temperature sensors 81 and 61 are a temperature control device 7 including a CPU, a ROM storing a control program, a RAM for temporarily storing data, and the like.
6 is electrically connected, and the measured temperature data is input to the temperature control device 76. The temperature control device 76 is electrically connected to the heater 55 and the pump 56 of the heat medium supply device 54, and the cooler 59 and the pump 60 of the refrigerant supply device 58, respectively.
Based on the temperature data of the outer mold 1 and the inner mold 2 measured by 1, 61, the heater 55 and the pump 56 of the heat medium supply device 54, the cooler 59 and the pump 60 of the refrigerant supply device 58 are controlled. is there. The temperature control device 76 forms temperature control means for controlling the outer die heating means, the inner die heating means, and the inner die cooling means, respectively.

In molding the belt with the molding apparatus formed as described above, first, as shown in FIG. 9 (a), the outer mold 1 and the inner mold 2 are separated from each other in the vertical direction, and the outer mold 1 is molded. A mold release agent is applied to the inner surface of the recess 39 and the outer surface of the core portion 42 of the inner mold 2, and a reinforcing core wire is wound around the outer periphery of the core portion 42 as necessary. In the process of applying the release agent and winding the core wire, the opening / closing valve 69 is opened to connect the delivery passage 66 and the delivery passage 67 for the outer mold and the delivery passage 66 and the delivery passage 68 for the inner mold. On-off valve 70 to close
Is closed, and the heat medium supplied from the heat medium supply device 54 is sent only to the heat medium flow path 50 of the outer mold 1 to heat the outer mold 1. The temperature of the outer mold 1 is set to a temperature at which the raw material resin liquid 4 is cross-linked (a temperature at which the cross-linking reaction of the raw material resin liquid 4 can proceed), and in the case of polyurethane, it is usually 100 to 120 ° C. When the temperature data of the outer mold 1 measured by the temperature sensor 81 is input to the temperature control device 76, the temperature of the outer mold 1 is adjusted based on the temperature data of the heater 5 of the heat medium supply device 54.
5 and the operation of the pump 56 are controlled by the temperature controller 76. That is, when the temperature measured by the temperature sensor 81 of the outer mold 1 is lower than the set value, the heat generation amount of the heater 55 is increased to increase the heat medium tank 65.
The temperature of the outer die 1 is controlled by increasing the temperature of the outer die 1 by increasing the temperature of the inner heat medium and increasing the amount of the heat medium delivered by the pump 56. Is higher than the set value, the amount of heat generated by the heater 55 is lowered to lower the temperature of the heat medium in the heat medium tank 65, and the amount of heat medium delivered by the pump 56 is reduced.
The temperature of the outer mold 1 is controlled so as to be lowered.

In the process of applying the release agent and winding the core wire, the switching valve 79 is switched so that the refrigerant delivery passage 77 and the inner die delivery passage 68 are communicated with each other, and the switching valve 80 is inside. The mold return passage 73 and the refrigerant return passage 78 are communicated with each other, and the inner mold return passage 73 and the return passage 7 are connected.
1, so that the refrigerant supplied from the refrigerant supply device 58 passes from the refrigerant delivery passage 77 through the inner die delivery passage 68 to the refrigerant passage 52 of the inner die 2 (at this time, the cavity portion 64). Becomes the coolant flow path 52) to cool the inner mold 2. The temperature of the inner mold 2 is set to be lower than the temperature of the outer mold 1, and it is preferably set to be lower by about 10 to 70 ° C. than that of the outer mold 1. Inner mold 2
When the temperature data of the inner mold 2 measured by the temperature sensor 61 is input to the temperature control device 76, the temperature of the refrigerant is operated based on the temperature data of the cooler 59 of the refrigerant supply device 58 and the pump 60. Is controlled by the temperature controller 76. That is, when the temperature measured by the temperature sensor 61 of the inner mold 2 is higher than the set value, the operation of the cooler 59 is increased to lower the temperature of the refrigerant, and the amount of refrigerant delivered by the pump 60 is increased to increase the inner mold. When the temperature measured by the temperature sensor 61 of the inner mold 2 is lower than the set value, the operation of the cooler 59 is lowered to raise the temperature of the refrigerant, and the pump is cooled. The amount of the refrigerant delivered by 60 is increased to control the temperature of the inner mold 2.

Next, as shown in FIG. 9A, the raw material resin liquid 4 such as polyurethane is supplied to the bottom of the molding recess 39 of the outer mold 1. In this way, when the raw resin liquid 4 is supplied, the temperature of the outer mold 1 is set to the temperature at which the raw resin liquid 4 is crosslinked, and the temperature of the inner mold 2 is set to a temperature lower than the temperature of the outer mold 1. ing. Thereafter, the outer die 1 is moved up or the inner die 2 is moved down to insert the core portion 42 of the inner die 2 into the molding recess 39 of the outer die 1. When the core portion 42 of the inner die 2 is deeply inserted into the molding recess 39 of the outer die 1, the lower end portion of the core portion 42 of the inner die 2 is molded by the outer die 1 as shown in FIG. 9B. The raw resin liquid 4 is inserted into the raw resin liquid 4 at the bottom of the working recess 39, and the raw resin liquid 4 is pressed between the lower surface of the core portion 42 and the bottom surface of the molding recess 39. As shown in FIG. 9 (b), the raw material resin liquid 4 pushed in this way is inside the cavity between the inner peripheral surface of the molding recess 39 of the outer mold 1 and the outer peripheral surface of the core part 42 of the inner mold 2. Can be pushed up. Then, by further completely inserting the core portion 42 of the inner mold 2 into the molding recess 39 of the outer mold 1, as shown in FIG.
The raw material resin liquid that is pushed up between the molding recess 39 and the core portion 42 into the molding cavity 3 formed between the inner peripheral surface of the molding recess 39 and the outer peripheral surface of the core portion 42 of the inner mold 2. 4 is filled.

Here, as described above, the raw material resin liquid 4 is pushed up and filled in the molding cavity 3 formed between the outer mold 1 and the inner mold 2 as the inner mold 2 is inserted into the outer mold 1. Since it is not necessary to inject the raw material resin liquid 4 while pressurizing it through the inlet, there is no problem that air is entrapped when the raw material resin liquid 4 is injected, and the raw material resin liquid 4 is also formed in the molding cavity. Since the liquid is filled while being pushed up into the molding cavity 3, the height of the liquid surface of the raw material resin liquid 4 in the molding cavity 3 is uniform, and the air is entrained in the raw material resin liquid 4 at the portion where the liquid level is low. Such problems will also disappear.

As described above, since the temperature of the outer mold 1 is set to the temperature at which the raw material resin liquid 4 is crosslinked, the raw material resin liquid 4 is crosslinked when the raw material resin liquid 4 is supplied into the outer mold 1. The core portion 42 of the inner mold 2 is inserted into the molding recess 39 of the outer mold 1 to fill the molding resin 3 in the molding cavity 3 between the outer mold 1 and the inner mold 2. Up to, the raw material resin liquid 4 is in a fluid state. After the raw material resin liquid 4 is filled in the molding cavity 3, both the open / close valves 69 and 70 are opened to allow the delivery passage 66 to communicate with both the outer die delivery passage 67 and the inner die delivery passage 68. The heat medium supplied from the heat medium supply device 54 is switched to the heat medium flow channel 50 of the outer mold 1 and the heat medium flow channel 51 of the inner mold 2 (in this case, the cavity 64 is the heat medium flow channel 51). Will be sent to both. At the same time, the switching valve 79 is switched so as to close the communication between the refrigerant delivery passage 77 and the inner die delivery passage 68, and the switching valve 80 closes the communication between the inner die return passage 73 and the refrigerant return passage 78. The inner mold return path 73 and the return path 71 are switched to communicate with each other. By passing the heat medium through the heat medium channel 50 of the outer mold 1 in this way,
The temperature of the inner mold 2 is raised by keeping the temperature of the outer mold 1 at a temperature at which the raw material resin liquid 4 is crosslinked and passing the heat medium through the heat medium flow passage 51 of the inner mold 2. It accelerates the crosslinking reaction of the raw material resin liquid 4.

The temperature of the inner mold 2 is kept at the temperature of the outer mold 1 while the raw resin liquid 4 is supplied into the outer mold 1 and the crosslinking is started from the time when the raw resin liquid 4 is crosslinked in the molding cavity 3. Since the temperature of the inner mold 2 is set to be lower than the temperature of 1, the temperature of the inner mold 2 will not be largely deprived by the raw material resin liquid 4 and the temperature of the inner mold 2 will not be greatly reduced. Therefore, due to the dimensional shrinkage of the inner mold 2 due to the temperature of the inner mold 2 being greatly reduced,
It is possible to prevent the diameter of the molding cavity 3 from becoming small, and it is possible to prevent the space between the inner peripheral surface of the outer mold 1 and the outer peripheral surface of the inner mold 2 from widening to increase the volume of the molding cavity 3. It is possible to prevent cracks from being formed in the molded product due to the increase in the volume of the molding cavity 3, and it is possible to reduce the occurrence of defective molding due to the cracks. It is preferable to set the temperature of the inner mold 2 at the time of starting the cross-linking to be lower than the temperature of the raw resin liquid 4 because the temperature of the inner mold 2 will not be deprived by the raw resin liquid 4. If it is too low, it takes time to raise the inner mold 2 to a temperature at which the crosslinking reaction of the raw material resin liquid 4 proceeds,
The time required for molding becomes long, and the productivity decreases. Therefore, the temperature of the inner mold 2 at the start of the cross-linking does not necessarily need to be set lower than the temperature of the raw material resin liquid 4, and may be lower than the temperature of the outer mold 1.

By passing the heat medium through the heat medium passage 50 of the outer mold 1 and the heat medium passage 51 of the inner mold 2 as described above, the temperature of the outer die 1 is maintained at a temperature at which the raw material resin liquid 4 is crosslinked. While the temperature of the inner mold 2 is gradually increased, these temperature adjustments are performed by the outer mold 1 measured by the temperature sensors 81 and 61.
As described above, based on the temperature data of the inner mold 2 and the heater 55 of the heat medium supply device 54 and the pump 5 by the temperature control device 76 as described above.
In addition to controlling the operation of No. 6, the temperature control device 76 controls the flow rate adjusting valves 74 and 75 provided in the outer mold return passage 72 and the inner mold return passage 73. That is, in order to maintain the temperature of the outer mold 1 at a temperature at which the raw material resin liquid 4 is crosslinked and at the same time increase the temperature of the inner mold 2, the heat generation amount of the heater 55 is increased to increase the temperature of the heat medium in the heat medium tank 65. The amount of heat medium delivered by the pump 56 is controlled to increase while increasing the amount, and the amount of heat medium to be passed through the heat medium passage 50 of the outer mold 1 and the heat medium passage 51 of the inner mold 2 is adjusted individually. Then, it is necessary to individually control the temperature of the outer mold 1 and the temperature of the inner mold 2. Therefore, based on the temperature data of the outer mold 1 and the inner mold 2 measured by the temperature sensors 81 and 61, temperature control of the flow rate adjusting valves 74 and 75 provided in the outer mold return path 72 and the inner mold return path 73 is performed. The heat medium passage 50 of the outer die 1 and the heat medium passage of the inner die 2 are controlled by the device 76 and the flow rate of the heat medium passing through the outer die return passage 72 and the inner die return passage 73 is adjusted. The amount of the heat medium passed through 51 is adjusted individually. That is, when the temperature of the outer mold 1 measured by the temperature sensor 81 is lower than the set value, the flow rate adjusting valve 74
Is increased to increase the flow rate of the heat medium to the heat medium flow path 50 of the outer die 1, and when the temperature of the outer die 1 measured by the temperature sensor 81 is higher than the set value, the opening of the flow rate adjusting valve 74 is opened. The flow rate of the heat medium to the heat medium flow passage 50 of the outer mold 1 is reduced to reduce the flow rate of the heat medium, and when the temperature rise of the inner mold 2 measured by the temperature sensor 61 is lower than the set value, The opening is enlarged to increase the flow rate of the heat medium to the heat medium passage 51 of the inner mold 2, and when the temperature rise of the inner mold 2 measured by the temperature sensor 61 is higher than the set value, the opening of the flow rate adjusting valve 75 is opened. By making it smaller, the flow rate of the heat medium to the heat medium flow passage 51 of the inner mold 2 is reduced.

The temperature of the inner mold 2 is at the end of crosslinking, that is,
At the time when the cross-linking of the raw material resin in the molding cavity 3 is completed and the three-dimensionalization of molecules is almost completed, and the molded product can be taken out from the molding cavity 3, the temperature becomes almost the same as the temperature of the outer mold 1. Is set to. At this time,
The temperature difference between the outer mold 1 and the inner mold should be within ± 10 ° C,
It is preferably ± 5 ° C. After the bridging is completed in this way, the opening / closing valve 69 is opened and the opening / closing valve 70 is closed, so that the delivery passage 66 and the outer die delivery passage 67 communicate with each other and the delivery passage 66 communicates with the inner die delivery passage 68. And the heat medium supplied from the heat medium supply device 54 is sent only to the heat medium flow passage 50 of the outer mold 1 to maintain the temperature at which the outer mold 1 crosslinks the raw material resin liquid 4. It is designed to be heated. At the same time, the switching valve 7
9 is switched so that the refrigerant delivery passage 77 and the inner die delivery passage 68 communicate with each other, and the switching valve 80 brings the inner die return passage 73 and the refrigerant return passage 78 into communication with each other and the inner die return passage 73 and the return passage The refrigerant supplied from the refrigerant supply device 58 is switched so as to close the communication with 71, and the refrigerant flow path 5 of the inner mold 2 passes from the refrigerant delivery passage 77 through the inner die delivery passage 68.
2 (in this case, the hollow portion 64 becomes the coolant channel 52), and the inner mold 2 is cooled to a temperature lower than that of the outer mold 1.

In this way, after cooling the inner mold 2, the outer mold 1
It is possible to obtain an annular belt by separating the inner mold 2 from the inner mold 2, removing the molded product from the molding cavity 3, taking out the molded product, and cutting the molded product into slices if necessary. After the molded product is demolded, the next molding described above is started. Here, as described above, by setting the temperature of the inner mold 2 at the start of crosslinking to a temperature lower than the temperature of the outer mold 1, it is possible to prevent the occurrence of defective molding due to cracks, and It becomes possible to use a fast raw material liquid. Therefore, the molding can be performed in a short crosslinking time to shorten the molding cycle, and the belt can be molded with high productivity.

Next, specific examples of the temperatures of the outer mold 1 and the inner mold 2 during one cycle from the demolding of the molding to the completion of filling and cooling will be shown.

That is, as the raw material resin liquid 4, a polyether urethane prepolymer and a curing agent 3,3'-
A liquid having a liquid temperature of 60 ° C. in which dicyclo-4,4′-diaminodiphenylmethane and a plasticizer of 30 phr were mixed was used, and an aromatic polyamide fiber was used as a core wire. Then, the temperature control device 76 controls the heat medium supply device 54, the coolant supply device 58, and the like as described above to perform molding while adjusting the temperatures of the outer mold 1 and the inner mold 2 as shown in Table 2.
No defective cracks occurred in the belt obtained by molding in this way.

[0070]

[Table 2] In the above-mentioned embodiment, the outer mold 1 is kept at a constant temperature for crosslinking the raw material resin liquid 4, but as shown in the following specific example, the mold release, the release agent coating, and the core wire winding. In the step of, the outer mold 1 may be cooled.

That is, as the raw material resin liquid 4, a polyether urethane prepolymer and a curing agent 3,3'-
A mixture of dicyclo-4,4'-diaminodiphenylmethane and 30 phr of a plasticizer having a liquid temperature of 60 ° C was used, and a polyester fiber was used as a core wire. Then, the temperature control device 76 controls the heat medium supply device 54, the coolant supply device 58, and the like as described above to perform molding while adjusting the temperatures of the outer mold 1 and the inner mold 2 as shown in Table 3. No defective cracks occurred in the belt obtained by molding in this way.

[0072]

[Table 3] In the embodiment shown in FIG. 8, the inner mold 2 is provided with the coolant channel 52, and the inner mold 2 is cooled by passing the coolant through the coolant channel 52. When cooling in a state that the inner mold 2 is separated from the outer mold 1 by molding,
This can be performed by blowing cool air onto the surface of the inner mold 2 to cool it by air. FIG. 10 shows an example thereof, in which a pair of air nozzles 83 attached to the frame body 43 is provided to form a blower device 53, and each air nozzle 8
3 is connected to an air pump or the like by an air pipe 84. The air pipe 84 is provided with a flow rate adjusting valve 85 formed of a solenoid valve or the like, and the flow rate adjusting valve 85 is electrically connected to the temperature control device 76 and is controlled by the temperature control device 76. . The blower device 53 described above
The inner cooling means is formed by this.

In this structure, the inner mold 2 is air-cooled by blowing air from the air nozzle 83 of the blower device 53 onto the surface of the inner mold 2. The temperature is measured by the temperature sensor 61 provided in the inner mold 2. The temperature control device 10 adjusts the flow rate adjusting valve 85 based on the temperature data of the inner mold 2 to control the temperature of the inner mold 2. That is, when the temperature measured by the temperature sensor 61 of the inner mold 2 is higher than the set value, the opening of the flow rate adjusting valve 85 is enlarged to increase the amount of air blown from the air nozzle 83 onto the surface of the inner mold 2, When the temperature measured by the temperature sensor 61 of the inner mold 2 is lower than the set value, the opening of the flow rate adjusting valve 85 is made smaller and the air nozzle 83 is controlled.
To reduce the amount of air blown onto the surface of the inner mold 2,
The temperature is controlled so as to raise the temperature of the inner mold 2.

Here, in the case where the inner mold 2 is cooled in a state of being separated from the outer mold 1 as described above, in addition to the type in which the temperature sensor 61 is embedded in the inner mold 2, as shown in FIG. A non-contact type thermometer 62 for measuring the temperature of the surface of the inner mold 2 from the outside of the inner mold 2 in a non-contact manner can be used. As the non-contact type thermometer 62, a radiation thermometer or the like that measures temperature using radiant heat can be used. The non-contact type thermometer 62 is moved forward and backward, and when measuring the temperature of the inner mold 2, the non-contact type thermometer 62 is moved forward to approach the inner mold 2, and after the temperature measurement is completed, the non-contact thermometer 62 is brought into non-contact. It is preferable to retract the mold thermometer 62 so that it is separated from the inner mold 2.

In the embodiment of FIG. 8, warm water, oil or the like is used as the heat medium, but it is possible to heat the outer mold 1 and the inner mold 2 by using steam as the heat medium. FIG. 11 shows an example thereof, and in FIG. 11, 57 is a steam supply device formed by a boiler or the like. A delivery path 66 and a return path 71 are connected to the steam supply device 57, and the delivery path 66 is the same as the case of FIG. 8 except that the pump 56 is not provided. The return path 7 is connected to the upper part of the heat medium flow path 50 of the outer mold 1 and the lower part of the heat medium flow path 51 of the inner mold 2 by a path 68.
Reference numeral 1 denotes an outer die return passage 72 and an inner die return passage 73, which are connected to the heat medium passage 50 of the outer die 1 and the heat medium passage 51 of the inner die 2, respectively. The outer mold delivery passage 67 and the inner mold delivery passage 68 are respectively provided with flow rate adjusting valves 86 and 87 formed of electromagnetic valves or the like, and the flow rate adjusting valves 86 and 87 are electrically connected to the temperature control device 76. Then, it is controlled by the temperature control device 76. Outer mold delivery path 67 and inner mold delivery path 68
In addition, the heat medium flow path 5 is provided more than the flow rate adjusting valves 86 and 87.
Pressure gauges 88 and 89 are provided on the 0, 51 side. The pressure gauges 88 and 89 are electrically connected to the temperature control device 76, and the data of the water vapor pressure of the water vapor in the outer die delivery passage 67 and the inner die delivery passage 68 measured by the pressure gauges 88 and 89. Is input to the temperature controller 76. The heating medium flow path 50 provided in the outer mold 1 and the steam supply device 57 that supplies the heating medium flow path 50 with steam form an outer mold heating means, and the inner mold 2
The inner medium heating means is formed by the heat medium passage 51 provided in the above and the steam supply device 57 that supplies water vapor to the heat medium passage 51. Further, an internal cooling means similar to that shown in FIG. 8 is also provided.

The steam heated by the steam supply device 57 is sent out through the delivery passage 66, and at the same time, through the open / close valve 69 opened from the delivery passage 66, through the outer die delivery passage 67, the heat transfer of the outer die 1 is performed. The outer mold 1 can be heated by the steam supplied to the passage 50. The steam in the heat medium flow path 50 is returned from the outer mold return path 72 to the steam supply device 57 through the return path 71. Here, the vapor may be released to the atmosphere without returning. Further, when the opening / closing valve 70 is opened, water vapor passes from the delivery passage 66 through the opening / closing valve 70 to the inner die delivery passage 68, and the heat medium flow path 5 of the inner die 2 is discharged.
1, the inner mold 2 can be heated by this steam. The water vapor in the heat medium passage 51 is returned to the inner mold return passage 7
3 is returned to the steam supply device 57 through the return passage 71. At this time, the steam may be released into the atmosphere without returning it. Further, pressure regulating valves 90 and 91 are provided in the outer die delivery passage 67 and the inner die delivery passage 68, respectively, so that the vapor pressures can be set individually to improve the temperature control accuracy. is there.

In this case, the temperature of the outer mold 1 and the inner mold 2 is adjusted by the temperature controller 76 based on the temperature data of the outer mold 1 and the inner mold 2 measured by the temperature sensors 81 and 61. This can be performed by controlling the adjusting valves 86 and 87 and adjusting the amount of water vapor supplied to the heat medium flow passages 50 and 51 of the outer die 1 and the inner die 2. That is, when the temperature measured by the temperature sensor 81 of the outer mold 1 is lower than the set value, the opening of the flow rate adjusting valve 86 is increased to increase the amount of water vapor supplied to the heat medium passage 50 of the outer mold 1. When the temperature measured by the temperature sensor 81 of the outer mold 1 is higher than the set value, the opening of the flow rate adjusting valve 86 is reduced to reduce the temperature of the outer mold 1. The amount of water vapor supplied to the heat medium flow path 50 is reduced, and the temperature of the outer mold 1 is controlled to be lowered. The water vapor pressure of the water vapor supplied to the heat medium flow passage 50 is measured by the pressure gauge 88, and the temperature control device 7
6 is input. Similarly, in the case of the inner mold 2, when the temperature measured by the temperature sensor 61 of the inner mold 2 is lower than the set value, the opening of the flow rate adjusting valve 87 is increased to increase the inner mold 2.
When the temperature of the inner mold 2 measured by the temperature sensor 61 is higher than the set value, the opening of the flow rate adjusting valve 87 is reduced to decrease the inner mold. The amount of water vapor supplied to the second heat medium flow passage 51 is reduced. The water vapor pressure of the water vapor supplied to the heat medium flow path 51 is measured by the pressure gauge 89 and input to the temperature control device 76.

In each of the above embodiments, the temperature of the outer mold 1 is set to the temperature at which the raw material resin liquid 4 is crosslinked at the start of the crosslinking of the raw resin liquid 4, and the temperature of the inner mold 2 is set to the temperature of the outer mold 1. The temperature of the inner mold 2 is set so that the temperature of the inner mold 2 becomes substantially equal to the temperature of the outer mold 1 at the end of the crosslinking, but on the contrary, the crosslinking of the raw material resin liquid 4 is started. At times, the temperature of the inner mold 2 is set to a temperature at which the raw material resin liquid 4 is crosslinked, and the temperature of the outer mold 1 is set to a temperature lower than the temperature of the inner mold 2. The outer mold 1 may be heated so that the temperature becomes substantially equal to the temperature of 2.

[0079]

As described above, in the belt molding method according to the first aspect of the present invention, the inner mold is inserted into the outer mold so that the inner peripheral surface of the outer mold and the outer peripheral surface of the inner mold are separated from each other. When the raw resin liquid between the outer mold and the inner mold is pushed up and filled in the molding cavity formed as a cavity between them, and then the raw resin liquid is cured in the molding cavity to mold the annular belt, The gas between the mold and the inner mold is discharged to reduce the pressure in the molding cavity, and the inner mold is inserted into the outer mold to push up the raw resin solution into the molding cavity to fill it. Since the depressurization is released at the same time, by depressurizing the molding cavity, the raw resin solution can be pushed up and filled into the molding cavity without the gas in the molding cavity coming into contact with the raw resin solution. , Which can prevent gas in the mold cavity is mixed into the starting resin solution,
Moreover, by releasing the reduced pressure immediately before or at the same time as the completion of the filling of the raw material resin liquid into the molding cavity, it is possible to prevent the generation of bubbles from the volatile components contained in the raw material resin liquid, It is possible to form a belt having no bubbles.

According to a second aspect of the present invention, in the above belt molding method, the degree of vacuum in the molding cavity is 5 mmHg.
Since the pressure is reduced below, it is possible to reliably prevent the gas remaining in the molding cavity from acting on the raw material resin liquid, and it is possible to mold the belt without bubbles.

According to a third aspect of the present invention, in the above belt molding method, the filling detection means detects the completion or the completion of the filling of the raw resin solution into the molding cavity, and the pressure is reduced based on the detection by the filling detection means. Therefore, the depressurization can be surely released immediately before the completion of the filling of the raw material resin liquid or at the time of the completion of the filling.

According to a fourth aspect of the present invention, in the above belt molding method, the filling detection means is formed using a limit switch, and the inner mold is inserted into the outer mold to insert the raw resin liquid into the molding cavity. Detecting the relative positional relationship between the outer mold and the inner mold just before filling is completed or when filling is completed with the limit switch, just before the completion of filling of the raw resin solution into the molding cavity or the completion of filling is detected. The limit switch detects the relative movement of the outer mold and the inner mold when the raw resin liquid is filled into the molding cavity, and it is possible to reliably detect the completion of filling or the completion of filling. Is something that can be done.

According to a fifth aspect of the present invention, in the above belt molding method, at the time of starting the cross-linking of the raw material resin liquid, the temperature of either the outer mold or the inner mold is set to the temperature at which the raw material resin liquid is cross-linked. Set the temperature of either the mold or the inner mold to a lower temperature, and heat the mold set to a lower temperature at the start of crosslinking so that the temperatures of the outer mold and the inner mold are approximately equal at the end of crosslinking. Therefore, it is possible to prevent cracks from being formed in the molded product due to the increase in the volume of the molding cavity, and it is possible to reduce the occurrence of molding defects due to the cracks.

According to a sixth aspect of the present invention, in the above belt molding method, the temperature of the outer mold is set to a temperature at which the raw material resin liquid is crosslinked at the start of crosslinking of the raw material resin liquid, and the temperature of the inner mold is set to the temperature of the outer mold. The temperature is set lower than the temperature, and the inner mold is heated so that the temperature of the inner mold is approximately equal to the temperature of the outer mold at the end of the cross-linking. The temperature of the inner mold, which is set to a low temperature, is not deprived of by the raw material resin liquid and the temperature of the inner mold does not drop significantly. It is possible to prevent the volume of the molding cavity between the inner peripheral surface of the mold and the outer peripheral surface of the inner mold from increasing, and the molded product cracks due to the increase in the volume of the molding cavity. To prevent Can, in which it is possible to reduce the occurrence of defective molding due to cracking. Since it is possible to prevent the occurrence of defective molding due to cracks in this way, it becomes possible to use a raw material resin liquid with a high crosslinking rate,
Molding can be performed with a short crosslinking time to shorten the molding cycle, and the belt can be molded with high productivity.

According to the invention of claim 7, in the above-mentioned method for molding a belt, the temperature of the inner mold is set to be lower than the temperature of the outer mold by cooling the inner mold after completion of the crosslinking. It is possible to immediately shift to the next molding cycle and improve the molding productivity.

According to the eighth aspect of the present invention, in the above belt forming method, the inner die is heated by passing a heating medium selected from hot water, oil and steam through the inner die, and cooling water is fed into the inner die. Since the inner mold is cooled by passing such a refrigerant, the heating and cooling of the inner mold can be efficiently performed by the action of the heat medium and the refrigerant.

According to the ninth aspect of the present invention, in the above belt molding method, since the inner mold is cooled by air-cooling the surface of the inner mold, the surface of the inner mold can be directly cooled. The inner mold can be cooled efficiently.

A belt forming apparatus according to a tenth aspect of the present invention is formed by including an outer die and an inner die, and by inserting the inner die into the outer die, an inner peripheral surface of the outer die is formed. An annular belt is formed by pushing up and filling the raw material resin liquid between the outer die and the inner die into a molding cavity formed as a cavity between the outer peripheral surface of the inner die and the inner die. In the molding apparatus for molding, the exhaust means for discharging the gas between the outer mold and the inner mold to reduce the pressure in the molding cavity,
Since the molding cavity is provided with the filling detection means for detecting the completion of the filling of the raw resin solution into the molding cavity or the completion of the filling, and the control means for releasing the decompression by the exhaust means based on the detection by the filling detection means By depressurizing the inside, the raw resin liquid can be pushed up and filled into the molding cavity without the gas inside the molding cavity coming into contact with the raw resin liquid, and the gas inside the molding cavity is mixed with the raw resin liquid. In addition to preventing this, the control means releases the reduced pressure immediately before or simultaneously with the completion of the filling of the raw material resin liquid into the molding cavity, whereby bubbles are generated from the volatile components contained in the raw material resin liquid. It is possible to prevent this, and it is possible to form a belt having no bubbles. Further, by controlling the exhaust means using the filling detection means and the control means, the depressurization can be automatically released immediately before the completion of the filling of the raw resin solution into the molding cavity or when the filling is completed, and the molding can be automated. It will be easier.

A belt forming apparatus according to an eleventh aspect of the present invention is formed by including an outer die and an inner die, and by inserting the inner die into the outer die, an inner peripheral surface of the outer die is formed. An annular belt is formed by pushing up and filling the raw material resin liquid between the outer die and the inner die into a molding cavity formed as a cavity between the outer peripheral surface of the inner die and the inner die. In the molding device for molding the resin, an exhaust port for discharging the gas between the outer mold and the inner mold to reduce the pressure inside the molding cavity is provided in the outer mold, and the molding cavity is filled with the raw resin solution immediately before or after the filling. Since the inner mold is provided with a flange that closes the communication between the exhaust port and the molding cavity when the inner mold is inserted into the outer mold, the material resin liquid is reduced by reducing the pressure inside the molding cavity through the exhaust port. In the molding cavity The raw resin liquid can be pushed up and filled into the molding cavity without contact with gas, and the gas in the molding cavity can be prevented from being mixed with the raw resin liquid, and the exhaust port and the molding cavity Bubbles are generated from the water content in the raw material resin liquid by closing the communication with the flange of the inner mold and releasing the decompression immediately before or at the same time when the filling of the raw material resin liquid into the molding cavity is completed. And a belt without bubbles can be formed. Further, the depressurization in the molding cavity is automatically performed in accordance with the operation of inserting the inner mold into the outer mold, and it is not necessary to provide the above-mentioned filling detection means and control means. Thus, the structure of the device can be simplified.

According to a twelfth aspect of the invention, in the above belt forming apparatus, an outer die heating means for heating the outer die, an inner die heating means for heating the inner die, and an inner die cooling means for cooling the inner die. When the cross-linking of the raw material resin is started, the outer mold is heated by the outer mold heating means so that the temperature of the outer mold becomes the temperature at which the raw material resin is cross-linked, and the temperature of the inner mold becomes lower than the temperature of the outer mold. In order to cool the inner mold with the inner mold cooling means, and to heat the inner mold with the inner mold heating means so that the temperature of the inner mold becomes substantially equal to the temperature of the outer mold at the time of completion of the crosslinking, Since the temperature control means for controlling the die heating means and the inner die cooling means respectively is provided, heating of the outer die can be performed when forming a belt with high productivity by reducing the occurrence of forming defects due to cracks as described above. Do not control the heating / cooling of the inner and inner molds with temperature control means. It can be performed et molding, in which the automation of molding is facilitated.

According to a thirteenth aspect of the present invention, in the above belt forming apparatus, the outer die heating means is formed by providing a heat medium passage for passing a heat medium provided in the outer die to heat the inner die. Since the means is formed by including the heat medium passage that is provided in the inner mold and allows the heat medium to pass therethrough, the heating of the outer mold and the inner mold can be efficiently performed by the action of the heat medium.

According to a fourteenth aspect of the present invention, in the above belt forming apparatus, the inner die cooling means is provided with a refrigerant passage for passing a refrigerant provided in the inner die. The inner mold can be cooled efficiently.

According to a fifteenth aspect of the present invention, in the above belt forming apparatus, the inner die cooling means is formed by an air blower that blows air onto the surface of the inner die to cool the inner die directly. Therefore, the inner mold can be efficiently cooled.

According to a sixteenth aspect of the present invention, in the above belt forming apparatus, the heat medium flow passage provided in the outer die and the heat medium supply device for supplying the heat medium to the heat medium flow passage have an outer mold. In addition to forming the heating means, the inner medium heating means is formed by the heat medium passage provided in the inner mold and the heat medium supply device for supplying the heat medium to the heat medium passage, and provided in the heat medium supply device. Since the heater that heats the heat medium and the pump that sends out the heat medium are controlled by the temperature control means, by adjusting the temperature of the heat medium by the heater and adjusting the amount of the heat medium delivered to the heat medium passage by the pump, The temperature of the outer mold and the inner mold can be accurately controlled.

According to a seventeenth aspect of the present invention, in the above belt forming apparatus, the outer die heating means includes a heat medium passage provided in the outer die and a steam supply device for supplying steam to the heat medium passage. And the heat medium flow path provided in the inner mold and the steam supply device for supplying steam to the heat medium flow path form the inner mold heating means, and the heat carrier flow of the outer mold from the steam supply device. Since the temperature control means controls the amount of water vapor supplied to the heat transfer passages of the inner and inner heat transfer channels, the temperature of the outer and inner molds can be accurately controlled by adjusting the amount of water vapor supplied to the heat transfer passages. Is something that can be done.

According to the eighteenth aspect of the present invention, in the above belt forming apparatus, the inner die cooling means is formed by the refrigerant passage provided in the inner die and the refrigerant supply device for supplying the refrigerant to the refrigerant passage. However, since the temperature control means controls the cooler for cooling the refrigerant provided in the refrigerant supply device and the pump for sending the refrigerant on the basis of the temperature of the inner mold measured by the temperature sensor, the temperature of the heat medium by the cooler is controlled. By adjusting the temperature and adjusting the amount of the refrigerant sent to the refrigerant passage by the pump, the temperature of the inner mold can be accurately controlled.

According to a nineteenth aspect of the present invention, in the above belt forming apparatus, a non-contact type thermometer for measuring the temperature of the inner mold is used as a temperature sensor for measuring the temperature of the inner mold. It is possible to measure the temperature of the inner mold from the outside of the inner mold without the need to incorporate a temperature sensor in.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of an embodiment of the present invention.

FIG. 2 is a cross-sectional view in one step of molding in the above embodiment.

FIG. 3 is a cross-sectional view in one step of molding in the above-described embodiment.

FIG. 4 is a block diagram of a control system in the above embodiment.

FIG. 5 is a cross-sectional view showing another example of the embodiment of the present invention.

FIG. 6 is a cross-sectional view in one step of molding in the above-described embodiment.

FIG. 7 is a cross-sectional view in one step of molding in the above-described embodiment.

FIG. 8 is a schematic diagram showing an example of another embodiment of the present invention.

FIG. 9 shows each step of forming the belt in the above-mentioned embodiment, and (a), (b) and (c) are sectional views, respectively.

FIG. 10 is a schematic view showing another example of the same embodiment.

FIG. 11 is a schematic view showing still another example of the same embodiment.

[Explanation of symbols]

1 External type 2 Internal type 3 molding cavity 4 Raw material resin liquid 6 limit switch 9 exhaust port 10 flange 50 heat medium flow path 51 Heat medium flow path 52 Refrigerant flow path 53 Blower 54 Heat medium supply device 55 heater 56 pumps 57 Water vapor supply device 58 Refrigerant supply device 59 Cooler 60 pumps 61 Temperature sensor 62 Non-contact thermometer

Front page continuation (51) Int.Cl. ⁷ Identification code FI // B29K 75:00 B29K 75:00 B29L 29:00 B29L 29:00 (72) Inventor Hiroyuki Matsumoto 4-chome, Hamazoe-dori, Nagata-ku, Hyogo Prefecture No. 21 in Mitsuboshi Belting Co., Ltd. (56) Reference JP-A-3-71818 (JP, A) JP-A-51-33157 (JP, A) JP-A-8-132458 (JP, A) JP-B-47 −32824 (JP, B1) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B29C 33/04-33/10 B29C 39/22-39/44 B29D 29/00-29/06

Claims (19)

(57) [Claims] 1. A molding cavity formed as a cavity between the inner peripheral surface of the outer mold and the outer peripheral surface of the inner mold by inserting the inner mold into the outer mold, and between the outer mold and the inner mold. When the raw resin solution is pushed up and filled, and then the raw resin solution is cured in the molding cavity to mold the annular belt, the gas between the outer mold and the inner mold is discharged to reduce the pressure in the molding cavity. At the same time, the inner mold is inserted into the outer mold to push up and fill the raw resin solution into the molding cavity, and the reduced pressure is released immediately before or at the same time as the completion of the filling. 2. The method for forming a belt according to claim 1, wherein the inside of the forming cavity is depressurized to a vacuum degree of 5 mmHg or less. 3. The filling detection means detects the completion of the filling of the raw resin solution into the molding cavity or the completion of the filling, and the depressurization is released based on the detection by the filling detection means. Or the method of forming a belt according to 2. 4. An outer mold in which the filling detection means is formed by using a limit switch, and the inner mold is inserted into the outer mold to complete the filling of the raw resin solution into the molding cavity or the filling is completed. 4. The limit switch is used to detect the relative positional relationship between the inner mold and the inner mold, so that the completion of the filling of the raw resin solution into the molding cavity or the completion of the filling is detected. The method for forming a belt according to any one of 1. 5. When starting the cross-linking of the raw material resin liquid, the temperature of either the outer mold or the inner mold is set to the temperature at which the raw material resin liquid is cross-linked, and the temperature of the other of the outer mold and the inner mold is set higher than that. The mold set to a low temperature at the start of the crosslinking is heated so that the temperature of the outer mold and the inner mold are set to be substantially equal at the end of the crosslinking, and the mold is heated. Belt molding method. 6. The temperature of the outer mold is set to the temperature at which the raw material resin liquid is crosslinked at the start of the crosslinking of the raw material resin liquid, and the temperature of the inner mold is set to a temperature lower than the temperature of the outer mold, and the internal temperature is set at the end of the crosslinking. The belt molding method according to claim 5, wherein the inner mold is heated so that the mold temperature becomes substantially equal to the outer mold temperature. 7. The method for molding a belt according to claim 6, wherein the temperature of the inner mold is set to a temperature lower than the temperature of the outer mold by cooling the inner mold after completion of the crosslinking. 8. The inner mold is heated by passing a heat medium selected from hot water, oil, and steam through the inner mold, and the inner mold is cooled by passing a refrigerant such as cooling water through the inner mold. The method for forming a belt according to any one of claims 5 to 7, characterized in that. 9. The method of molding a belt according to claim 5, wherein the inner mold is cooled by air-cooling the surface of the inner mold. 10. A cavity formed between an inner peripheral surface of the outer mold and an outer peripheral surface of the inner mold by forming the outer mold and the inner mold by inserting the inner mold into the outer mold. In a molding device that pushes up and fills a raw material resin liquid between an outer mold and an inner mold into a molding cavity to be formed and cures the raw material resin liquid in the molding cavity to mold an annular belt, Exhaust means for discharging the gas between the molding cavities to reduce the pressure in the molding cavity, a filling detection means for detecting the completion or the completion of the filling of the raw resin solution into the molding cavity, and an exhaust means based on the detection by the filling detection means. And a control means for releasing the reduced pressure by the belt forming apparatus. 11. A cavity formed between an inner peripheral surface of the outer mold and an outer peripheral surface of the inner mold by forming the outer mold and the inner mold by inserting the inner mold into the outer mold. In a molding device that pushes up and fills a raw material resin liquid between an outer mold and an inner mold into a molding cavity to be formed and cures the raw material resin liquid in the molding cavity to mold an annular belt, The outer mold is provided with an exhaust port for discharging the gas between the mold cavity and decompressing the inside of the molding cavity, and the inner mold is inserted into the outer mold immediately before or until the completion of the filling of the raw resin solution into the molding cavity. A belt forming apparatus, wherein a flange for closing the communication between the exhaust port and the forming cavity is sometimes provided in the inner mold. 12. An outer die heating means for heating an outer die, an inner die heating means for heating an inner die, an inner die cooling means for cooling the inner die, and a temperature of the outer die is a raw material at the time of starting the crosslinking of the raw material resin. The outer mold is heated by the outer mold heating means so as to reach the temperature for crosslinking the resin, and the inner mold is cooled by the inner mold cooling means so that the temperature of the inner mold becomes lower than the temperature of the outer mold, and cross-linked. At the time of completion, the temperature control for controlling the outer mold heating means, the inner mold heating means, and the inner mold cooling means so that the inner mold heating means heats the inner mold so that the temperature of the inner mold becomes substantially equal to the temperature of the outer mold. The belt forming apparatus according to claim 10 or 11, further comprising means. 13. The outer die heating means is formed by providing a heat medium flow passage through which a heat medium provided in the outer die passes, and the inner die heating means passes through a heat medium provided in the inner die. The belt forming apparatus according to claim 12, wherein the belt forming apparatus is formed by including a heat medium passage. 14. The belt forming apparatus according to claim 12, wherein the inner die cooling means is formed by including a refrigerant passage provided in the inner die for passing a refrigerant. 15. The belt molding apparatus according to claim 12, wherein the inner mold cooling means is formed by a blower that blows air onto the surface of the inner mold to cool the inner mold. 16. A heat medium flow path provided in the outer mold and a heat medium supply device for supplying the heat medium to the heat medium flow path form an outer mold heating means and heat provided in the inner mold. A medium flow path and a heat medium supply device that supplies the heat medium to the heat medium flow path form an internal heating means, and a heater that heats the heat medium provided in the heat medium supply device and a pump that sends out the heat medium are provided. The belt molding apparatus according to claim 12 or 13, wherein the belt molding apparatus is controlled by a temperature control means. 17. A heating medium flow path provided in the inner mold, together with a heating medium flow path provided in the inner mold and a heating medium flow path provided in the outer mold and a steam supply device for supplying steam to the heating medium flow path. Road,
An inner heating means is formed with a steam supply device that supplies steam to the heat medium passage, and the amount of steam supplied from the steam supply device to the outer heat medium passage and the inner heat medium passage is controlled by the temperature. 2. The control means is controlled by the control means.
The belt forming apparatus according to 2 or 13. 18. A cooler that cools the refrigerant provided in the refrigerant supply device by forming the internal mold cooling means with the refrigerant flow path provided in the internal mold and the refrigerant supply device that supplies the refrigerant to the refrigerant flow path. 13. A temperature control means controls a pump for sending out the refrigerant and the pump for sending out the refrigerant based on the temperature of the inner mold measured by the temperature sensor.
18. The belt forming apparatus according to any one of 17 above. 19. The belt forming apparatus according to claim 12, wherein a non-contact type thermometer that measures the temperature in a non-contact manner is used as a temperature sensor that measures the temperature of the inner mold. .