JP2004196596A - Induction heating molding apparatus and induction heating molding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an induction heating molding apparatus which can efficiently and separately perform the induction heating of an upper mold and a lower mold each equipped with an induction coil and an induction heating molding method using the apparatus. <P>SOLUTION: The induction heating molding apparatus melts and molds an optical element material or the like sealed in a mold by performing the induction heating of an upper mold 1a and a lower mold 1b by applying electric current to an induction coil 2a for the upper mold and an induction coil 2b for the lower mold. In the molding apparatus, a control device 4 controls the output electric power of an inverter 3 on the basis of measured values obtained by an upper-mold temperature measurement means 6a and a lower-mold temperature measurement means 6b; and the positions of the induction coil 2a for the upper mold and the induction coil 2b for the lower mold are adjusted with an induction coil position adjustment means 7a for the upper mold and an induction coil position adjustment means 7b for the lower mold, respectively. Since adjusting the positions of the induction coils 2a and 2b can make the magnetic flux passing through the upper mold 1a different from that passing through the lower mold 1b, the temperatures of the upper mold 1a and the lower mold 1b can be independently controlled. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an induction heating molding apparatus and an induction heating molding method for molding an optical element material and the like.
[0002]
[Prior art]
Conventionally, a molding apparatus as shown in FIG. 7 has been used for molding an optical element material. This molding apparatus includes a molding die 1 divided into an upper die 1a and a lower die 1b using a magnetic material or the like, and an induction coil 2a for an upper die for induction heating each of the upper die 1a and the lower die 1b. An induction coil 2b for a lower die (hereinafter simply referred to as induction coils 2a and 2b), an inverter 3 for supplying high-frequency power to the induction coils 2a and 2b, and an upper die 1a and a lower die so as to realize a desired molding process. And a control device 4 for controlling the temperature of 1b.
[0003]
Reference numerals 5a and 5b denote an upper die moving mechanism and a lower die moving mechanism for moving the upper die 1a and the lower die 1b in the vertical direction when a molding material is charged or a molded product is taken out, respectively, and 6a and 6b are upper die respectively. An upper mold temperature measuring means and a lower mold temperature measuring means for measuring the temperatures of the lower mold 1a and the lower mold 1b and outputting an electric signal corresponding to the measured value to the control device 4.
[0004]
Then, the upper mold 1a and the lower mold 1b are induction-heated by the inverter 3 and the induction coils 2a and 2b, so that the molding material (glass block as an optical element material) sealed in the mold is heated and molded by heat conduction. I have to.
[0005]
At this time, the temperature of the upper mold 1a and the lower mold 1b are directly controlled by the control device 4, thereby realizing high-efficiency and high-precision molding, and separately adjusting the temperatures of the upper mold 1a and the lower mold 1b. By doing so, the thermal expansion of the mold material and the molding material is controlled, and the releasability of removing the molded product from the upper mold 1a and the lower mold 1b is improved.
[0006]
By the way, when the upper mold 1a and the lower mold 1b are separately induction-heated by the two induction coils 2a and 2b whose magnetic flux is on the same axis as shown in the figure, the following problem occurs.
[0007]
As a first problem, when a separate inverter circuit (drive circuit) is provided for each of the induction coils 2a and 2b, when one induction coil is driven and the other induction coil is not driven, the non-drive circuit is inductively coupled. In this case, an induced electromotive force is applied to the power supply and power cannot be consumed, which may damage circuit elements such as drive elements.
[0008]
Therefore, as shown in the figure, a method has been proposed in which one inverter 3 is provided in common to the two induction coils 2a and 2b, and the connection of the inverter 3 to each of the induction coils 2a and 2b is switched by the connection switching means 21a and 21b. (For example, see Patent Document 1).
[0009]
As a second problem, magnetic flux interference occurs between the two induction coils 2a and 2b, that is, if an attempt is made to control the magnetic flux of one induction coil, it will affect the other induction coil, and independent control will occur. Have difficulty.
[0010]
Therefore, as shown, resonance capacitors 22a and 22b are provided in series with the two induction coils 2a and 2b, respectively, and the inverter circuit of the inverter circuit is designed around different resonance frequencies designed for the upper mold 1a and the lower mold 1b. A method of controlling the current flowing through the induction coils 2a and 2b by changing the oscillation frequency has been proposed (for example, see Patent Document 2).
[0011]
[Patent Document 1]
JP-A-4-58491
[Patent Document 2]
JP-A-6-64932
[Problems to be solved by the invention]
However, as described above, depending on the method of switching the connection of the inverter 3 to the induction coils 2a and 2b, the induced electromotive force generated in the induction coil that is not driven does not return to the drive circuit, which may lead to breakage of the drive circuit. However, since there is no return destination of the induced electromotive force, it needs to be consumed by a circuit including a transmission line on the load side, which leads to heat consumption in a conductive wire or the like, which may cause a heat-resistant damage to the coating.
[0014]
Further, in the method of controlling the current flowing through the induction coils 2a and 2b by changing the oscillation frequency of the inverter circuit by the resonance capacitors 22a and 22b, it is necessary to drive the inverter at a portion outside the resonance point of the circuit. In addition, there is a problem that power reflection or the like occurs constantly and the efficiency of the inverter is reduced.
[0015]
An object of the present invention is to solve the above-mentioned problem, and an object of the present invention is to provide an induction heating molding apparatus and an induction heating molding method capable of independently and efficiently induction heating an upper die and a lower die each equipped with an induction coil.
[0016]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides an upper mold and a lower mold which are divided into upper and lower parts, an induction coil for an upper mold and an induction coil for a lower mold, the induction coil for the upper mold and an induction coil for the lower mold. An inverter for supplying high-frequency power to the coil is provided, and the upper and lower molds are induction-heated by energizing the upper and lower mold induction coils, and enclosed in the upper and lower molds. An induction heating molding device for melting and molding the formed material, a temperature measuring means for measuring respective temperatures of the upper mold and the lower mold, and an output of the inverter to the induction coil for the upper mold and the induction coil for the lower mold. Inverter output power adjusting means for adjusting the power, upper induction coil position adjusting means for adjusting the position of the upper die induction coil, and lower die induction adjusting the position of the lower die induction coil Characterized by being configured to include a yl positioning means.
[0017]
Further, the present invention provides an upper mold and a lower mold for forming divided into upper and lower parts, an induction coil for the upper mold and an induction coil for the lower mold, and a high-frequency power supply to the induction coil for the upper mold and the induction coil for the lower mold. And an inverter that conducts electricity to the induction coil for the upper die and the induction coil for the lower die, thereby inductively heating the upper die and the lower die, and melting the material sealed in the upper die and the lower die. Temperature measuring means for measuring the temperature of each of the upper mold and the lower mold, and an inverter output for adjusting the output power of the inverter with respect to the induction coil for the upper mold and the induction coil for the lower mold. Power adjusting means, and coil voltage dividing means for dividing a secondary coil of an insulating transformer for electrically insulating the upper and lower mold induction coils from the inverter. Characterized in that it was formed.
[0018]
Further, the present invention, by supplying high-frequency power to the induction coil for the upper die and the induction coil for the lower die, induction heating of the upper die and the lower die, when melting and molding the material enclosed in the die, The temperature of each of the upper mold and the lower mold is measured, and based on the measured value, the output power of the inverter that supplies the high-frequency power is adjusted, and the upper mold induction coil for the upper mold and the lower mold and The temperature of the upper die and the lower die are independently controlled by adjusting at least one position of the induction coil for the lower die.
[0019]
Preferably, of the upper mold and the lower mold, for one of the molds whose temperature is to be set higher, the amount of adjustment of the output power of the inverter is calculated from the difference between the measured mold temperature and the target temperature, and based on the calculated value. By adjusting the output power of the inverter so that the mold temperature follows the target temperature, and for the other mold whose temperature is to be set lower, the induction for the upper mold or the lower mold is determined based on the difference between the measured mold temperature and the target temperature. An amount of adjustment of the position of the coil is calculated, and the position of the induction coil for the upper die or the lower die is adjusted based on the calculated value so that the die temperature follows the target temperature.
[0020]
In addition, the present invention provides high-frequency power to the induction coil for the upper die and the induction coil for the lower die, thereby inductively heating the upper die and the lower die, and melting and molding the material sealed in the die. The temperature of each of the upper mold and the lower mold is measured, and based on the measured value, the output power of the inverter that supplies the high frequency power is adjusted, and the induction coil for the upper mold and the induction coil for the lower mold, The temperature of the upper mold and the lower mold are independently controlled by adjusting the partial pressure of the secondary coil of the insulating transformer that electrically insulates the inverter from the inverter.
[0021]
Preferably, of the upper mold and the lower mold, for one of the molds whose temperature is to be set higher, the amount of adjustment of the output power of the inverter is calculated from the difference between the measured mold temperature and the target temperature, and based on the calculated value. By adjusting the output power of the inverter to make the mold temperature follow the target temperature, and for the other mold whose temperature is to be set lower, the amount of adjustment of the partial pressure of the coil is calculated from the difference between the measured mold temperature and the target temperature. Calculate and adjust the partial pressure of the coil based on the calculated value.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 is a schematic configuration diagram of an induction heating molding apparatus according to Embodiment 1 of the present invention.
[0023]
In FIG. 1, an induction heating device provided for a molding die 1 includes an upper die 1a and a lower die 1b formed separately, and an induction coil 2a for an upper die for induction heating the upper die 1a and the lower die 1b, respectively. , A lower mold induction coil 2b, an inverter 3 for supplying high frequency power to the upper mold induction coil 2a and the lower mold induction coil 2b, and an upper mold 1a and a lower mold 1b so as to realize a desired molding process. A control device 4 for controlling the temperature.
[0024]
More specifically, the upper mold 1a and the lower mold 1b are formed by shaping a molding material to form a desired shape, and a magnetic material that easily heats the inside of the mold to a desired temperature. It is created using For example, when the molding material is a glass material, a magnetic material that is easily heated to 600 ° C., for example, stainless steel SUS410 or NiAl is used. For the inner surface of the mold that comes into contact with the molding material, a material that is difficult to adhere even when the glass material is melted, such as silicon carbide, is used.
[0025]
An upper die moving mechanism that is driven by a driving means such as a motor when a molding material is charged or a molded product is taken out of the upper die 1a and the lower die 1b to move the upper die 1a and the lower die 1b in the vertical direction. 5a and the lower die moving mechanism 5b are connected.
[0026]
The upper mold 1a and the lower mold 1b each detect the temperature of the upper mold 1a and the lower mold 1b with a detection unit inserted inside the mold, and output an electric signal corresponding to the detected value to the control device 4. A temperature measuring means 6a and a lower mold temperature measuring means 6b are provided.
[0027]
Further, the upper-type induction coil 2a and the lower-type induction coil 2b are respectively provided with an upper-type induction coil position adjusting means 7a for adjusting the relative position of the upper-type induction coil 2a and the lower-type induction coil 1b in the vertical direction, and the lower-type induction coil. The position adjusting means 7b is connected. The induction coil position adjusting means 7a and 7b are driven by driving means such as a motor.
[0028]
Also, an upper-type resonance capacitor 8a and a lower-type resonance capacitor 8b for causing high-frequency resonance are connected in series with the upper-type induction coil 2a and the lower-type induction coil 2b, respectively.
[0029]
The inverter 3 is configured to be driven by a series resonance type inverter system. The output power is adjusted by adjusting the energization time of a power element constituting the inverter 3 by an external input means, for example, a digital I / O input. Can be changed.
[0030]
The inverter 3 is insulated from the upper induction coil 2a and the lower induction coil 2b by the insulating transformer 9, and is protected from a large current flowing to the induction coils 2a and 2b by resonance.
[0031]
The control device 4 sets the temperatures of the upper mold 1a and the lower mold 1b to target temperatures based on the target temperature and the measured temperatures input from the upper mold temperature measuring means 6a and the lower mold temperature measuring means 6b, as described later. The temperature to be followed is controlled.
[0032]
The operation of the above configuration will be described.
A molding material is supplied into the upper mold 1a and the lower mold 1b, and electric power is supplied from the inverter 3 to each of the induction coils 2a and 2b, so that the upper mold 1a and the lower mold 1b are induction-heated to perform the upper mold 1a and the lower mold. The molding material in 1b is heated and molded by heat conduction.
[0033]
Specifically, at the time of supplying the molding material, an interval is set between the upper mold 1a and the lower mold 1b such that the molding material can be inserted. For example, when the molding material is a glass ball having a diameter of about 10 mm, an interval of about 30 mm is provided. deep. After the molding material is inserted, the gap between the upper mold 1a and the lower mold 1b is clamped by the moving mechanisms 5a and 5b. At that time, with one of the upper mold 1a and the lower mold 1b fixed, the other is moved until it comes into contact with the molding material, and a constant load, for example, about 20 kgf is applied.
[0034]
In this state, the upper die 1a and the lower die 1b are induction-heated by supplying high frequency power from the inverter 3 to each of the induction coils 2a and 2b. For example, when a high frequency power of 23 kHz is supplied to the induction coil 2a, a magnetic flux is generated inside the induction coil 2a, an induction current flows through the upper die 1a through which the magnetic flux passes, and the induction coil 2a and the upper die 1a are inductively coupled. Therefore, the upper mold 1a can be induction-heated. Similarly, the lower mold 1b can be induction-heated by the induction coil 2b.
[0035]
Since the molding material is melted and elastically deformed as the temperatures of the upper mold 1a and the lower mold 1b rise, a pressing load of about 350 kgf is applied by the upper mold moving mechanism 5a and the lower mold moving mechanism 5b. At this time, the temperature of the molding material has risen to about 585 ° C. In order to transfer the mold shape to this molding material, the temperatures of the upper mold 1a and the lower mold 1b are lowered to about 550 ° C, while the upper mold is moved. The pressing load by the mechanism 5a and the lower mold moving mechanism 5b is reduced to about 50 kgf. Then, a molded product molded by such a series of molding processes is taken out by widening the interval between the upper mold 1a and the lower mold 1b.
[0036]
At this time, by using a certain procedure of releasing the upper die 1a and then releasing the lower die 1b, workability is enhanced and removal is facilitated. For this purpose, for example, the temperature is lowered while maintaining the temperature of the lower mold 1b at about 100 ° C. higher than the temperature of the upper mold 1a. Then, for example, when the upper mold temperature reaches 450 ° C. and the lower mold temperature reaches 550 ° C., the moving mechanism 5a is moved upward to release the upper mold 1a. After the release of the upper mold 1a, the temperature of the lower mold 1b is lowered to near room temperature, and the molded product in the lower mold 1b is taken out.
[0037]
Hereinafter, the temperature control method will be described.
As described above, the control device 4 independently controls the temperature of the upper mold 1a and the lower mold 1b based on the target temperature and the measured temperatures input from the temperature measuring means 6a and 6b. For this purpose, a desired operation amount is calculated using a general PID control method, and 1) input power operation for outputting the calculated operation amount to the above-described external input means for inverter output power adjustment; and 2) calculation. The coil relative position operation for outputting the operation amount to the driving means of the induction coil position adjusting means 7a, 7b is performed.
[0038]
Of the upper die 1a and the lower die 1b, the lower die 1b having a higher target temperature is controlled by the input power operation. For example, the mold temperature is controlled by adjusting the applied power in accordance with the relationship between the applied time and the mold temperature (determined in advance) for the applied powers P1, P2, P3, P4,... As shown in FIG. .
[0039]
The upper mold 1a having the lower target temperature is controlled by the coil relative position operation. For example, according to the relationship between the coil relative position and the mold temperature for input powers P1, P2, P3,... As shown in FIG. 3 (determined in advance), the coil relative position which is the position of the induction coil 2a with respect to the upper mold 1a. By adjusting the position, the mold temperature is controlled. For example, when it is desired to change the mold temperature from T2 to T2a at the input power P2, the coil relative position is changed from ΔS1 to ΔS2. In order to follow the target temperature with high accuracy, the operation amount of the PID control is made to correspond to the movement amount of the induction coil position adjusting means 7a, 7b directly connected to the induction coils 2a, 2b.
[0040]
In other words, utilizing the fact that the magnetic flux becomes smaller outside the end faces of the induction coils 2a and 2b than in the induction coils 2a and 2b, the lower mold 1b having a higher target temperature is controlled to a desired temperature by the input power operation. The upper mold 1a having a lower target temperature is operated by operating the coil relative position such that the upper mold induction coil 2a coupled to the upper mold 1a is located outside the end face of the upper mold 1a. The magnetic flux penetrating 1a is reduced to control the temperature to a desired value.
[0041]
By doing so, problems such as heat-resistant damage to the coating, which occurred in the conventional method of switching the connection of the inverter circuit (drive circuit) to each induction coil, and changing the oscillation frequency of the inverter circuit by the resonance capacitor can be achieved. It is possible to avoid problems such as a decrease in the efficiency of the inverter, which occur in the conventional method of controlling the current flowing through each induction coil.
(Embodiment 2)
FIG. 4 is a schematic configuration diagram of an induction heating molding apparatus according to Embodiment 2 of the present invention.
[0042]
Since the induction heating molding apparatus according to the second embodiment has substantially the same configuration as the apparatus according to the first embodiment described above with reference to FIG. 1, the same operation as that shown in FIG. The same reference numerals as in FIG. 1 denote the same members, and a detailed description thereof will be omitted.
[0043]
The difference between the induction heating molding apparatus of the second embodiment and the apparatus of the first embodiment is that the induction coil position adjusting means 7a for the upper die and the induction coil position for the lower die which are provided in the apparatus of the first embodiment. The difference is that a coil voltage dividing means 10 for dividing the induced voltage applied to the secondary coil 9a of the insulating transformer 9 is connected to the control device 4 instead of the adjusting means 7b.
[0044]
The coil voltage dividing means 10 is provided movably along the arrangement direction of a plurality of voltage division switching points (tap positions N1 to Nn) provided on the secondary coil 9a, and has one end with respect to each voltage division switching point. And has a connecting portion 10a connected at the other end to a connection point 2c of the upper induction coil 2a and the lower induction coil 2b.
[0045]
In the induction heating molding apparatus according to the second embodiment, similarly to the induction heating molding apparatus according to the first embodiment, the upper die 1a and the lower die 1b are induced by supplying electric power from the inverter 3 to the induction coils 2a and 2b. The molding material in the mold is heated and molded by heating.
[0046]
At this time, the control device 4 independently controls the temperature of the upper mold 1a and the lower mold 1b based on the target temperature and the measured temperatures input from the upper mold temperature measuring means 6a and the lower mold temperature measuring means 6b.
[0047]
However, the control device 4 calculates a desired operation amount using a general PID control method, and 1) input power operation for outputting the calculated operation amount to the above-mentioned external input means for inverter output power adjustment; And (3) performing a voltage division position operation of outputting the calculated operation amount to the coil voltage dividing means 10.
[0048]
Among the upper mold 1a and the lower mold 1b, the one with the higher target temperature is temperature control by the input power operation, and the one with the lower target temperature is temperature control by the position operation of the coil voltage dividing means 10.
[0049]
For example, the lower mold 1b having a higher target temperature is controlled by the input power operation. The mold temperature is controlled by adjusting the applied power according to the relationship between the applied time and the mold temperature for the applied powers P1, P2, P3, P4,... As shown in FIG.
[0050]
The upper die 1a having the lower target temperature is controlled by the position of the coil voltage dividing means 10. For example, the inductive load inductance corresponding to the mold temperature is determined from the relationship between the inductive load inductance and the mold temperature for the input powers P1, P2, P3,... As shown in FIG. For example, when it is desired to set the mold temperature to T3 at the input power P2, the inductive load inductance is obtained as L3. Further, from the relationship between the tap position and the inductive load inductance as shown in FIG. 6, the tap position at which the upper die induction coil 2a becomes L3 is determined as N1. Then, the connecting portion 10a of the coil voltage dividing means 10 is moved to the tap position N1. In order to follow the target temperature with high accuracy, the operation amount of the PID control is made to correspond to the movement amount of the connecting portion 10a of the coil voltage dividing means 10.
[0051]
That is, utilizing the fact that the inductive load of the coil can be adjusted by the coil voltage dividing means 10, the lower mold 1b having the higher target temperature can be controlled to the desired temperature by the input power operation while the target temperature is higher. The lower upper mold 1a controls the inductance of the upper mold induction coil 2a coupled to the upper mold 1a to reduce the magnetic flux for induction heating and control the temperature to a desired temperature.
[0052]
By doing so, problems such as heat-resistant damage to the coating, which occurred in the conventional method of switching the connection of the inverter circuit (drive circuit) to each induction coil, and changing the oscillation frequency of the inverter circuit by the resonance capacitor can be achieved. It is possible to avoid problems such as a decrease in the efficiency of the inverter, which occur in the conventional method of controlling the current flowing through each induction coil.
[0053]
【The invention's effect】
As described above, according to the present invention, the output power of the inverter is adjusted via the inverter output power adjusting means based on the measurement value measured by the temperature measuring means, and the upper die induction coil position adjusting means and the lower By adjusting the position of the induction coil for the upper die and the induction coil for the lower die via the induction coil position adjusting means for the die, the magnetic flux penetrating through the upper die and the lower die are made different from each other, so that the upper die and the lower die are formed. Independent temperature control becomes possible.
[0054]
Further, based on the measurement value measured by the temperature measuring means, the output power of the inverter is adjusted via the inverter output power adjusting means, and the induction coil for the upper die and the induction coil for the lower die are adjusted via the coil partial pressure adjusting means. By adjusting the partial pressure of the coil and making the inductances of the induction coil for the upper die and the induction coil for the lower die different from each other, the temperature of the upper die and the lower die can be controlled independently.
[0055]
Therefore, there is a problem such as heat-resistant damage of the coating which has occurred in the conventional method of switching the connection of the inverter circuit (drive circuit) to each induction coil, and the current flows through each induction coil by changing the oscillation frequency of the inverter circuit by the resonance capacitor. It is possible to avoid problems such as a decrease in the efficiency of the inverter, which occur in the conventional method of controlling the current.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an induction heating molding apparatus according to a first embodiment of the present invention. FIG. 2 is a graph showing a relationship between a power input time and a mold temperature during induction heating. FIG. Fig. 4 is a graph showing the relationship between the relative position of the induction load to the mold due to the input power and the mold temperature at the time. Fig. 4 is a schematic configuration diagram of the induction heating forming apparatus according to the second embodiment of the present invention. FIG. 6 is a graph showing a relationship between temperature and FIG. 6 is a graph showing a relationship between a tap position for dividing an induced voltage applied to a secondary coil of an insulation transformer and upper and lower types of inductive load inductances. Schematic diagram of induction heating molding equipment
1a Upper die 1b Lower die 2a Upper die induction coil 2b Lower die induction coil 3 Inverter 4 Controller 5a Upper die moving mechanism 5b Lower die moving mechanism 6a Upper die temperature measuring means 6b Lower die temperature measuring means 7a Upper die guiding Coil position adjusting means 7b Lower die induction coil position adjusting means 9 Insulation transformer 10 Coil voltage dividing means

Claims (6)

An upper and lower mold for forming divided into upper and lower parts, an induction coil for upper mold and an induction coil for lower mold, and an inverter for supplying high-frequency power to the induction coil for upper and lower molds Induction heating for inductively heating the upper and lower dies by energizing the induction coil for the upper and lower dies and melting and molding the material sealed in the upper and lower dies. A molding device,
Temperature measuring means for measuring the temperature of each of the upper mold and the lower mold,
Inverter output power adjusting means for adjusting the output power of the inverter with respect to the upper mold induction coil and the lower mold induction coil,
Upper die induction coil position adjusting means for adjusting the position of the upper die induction coil,
An induction heating and forming apparatus comprising: a lower die induction coil position adjusting means for adjusting a position of the lower die induction coil. An upper and lower mold for forming divided into upper and lower parts, an induction coil for upper mold and an induction coil for lower mold, and an inverter for supplying high-frequency power to the induction coil for upper and lower molds Induction heating for inductively heating the upper and lower dies by energizing the induction coil for the upper and lower dies and melting and molding the material sealed in the upper and lower dies. A molding device,
Temperature measuring means for measuring the temperature of each of the upper mold and the lower mold,
Inverter output power adjusting means for adjusting the output power of the inverter with respect to the upper mold induction coil and the lower mold induction coil,
An induction heating and forming apparatus comprising: coil voltage dividing means for dividing a secondary coil of an insulating transformer for electrically insulating the upper and lower induction coils from an inverter. By supplying high-frequency power to the induction coil for the upper die and the induction coil for the lower die, the upper die and the lower die are induction-heated, and when the material enclosed in the die is melted and molded,
The temperature of each of the upper mold and the lower mold is measured, and based on the measured value, the output power of the inverter that supplies the high-frequency power is adjusted, and the upper mold induction coil for the upper mold and the lower mold and An induction heating molding method, wherein the temperature of the upper die and the lower die is independently controlled by adjusting at least one position of the induction coil for the lower die. Of the upper mold and the lower mold, for one of the molds whose temperature is desired to be set higher, an adjustment amount of the output power of the inverter is calculated from the difference between the measured mold temperature and the target temperature, and based on the calculated value, Adjust the output power so that the mold temperature follows the target temperature, and for the other mold whose temperature you want to set lower, determine the position of the induction coil for the upper or lower mold based on the difference between the measured mold temperature and the target temperature. 4. The induction heating molding according to claim 3, wherein the amount of adjustment is calculated, and the position of the induction coil for the upper die or the lower die is adjusted based on the calculated value so that the die temperature follows the target temperature. Method. By supplying high-frequency power to the induction coil for the upper die and the induction coil for the lower die, the upper die and the lower die are induction-heated, and when the material enclosed in the die is melted and molded,
The temperature of each of the upper mold and the lower mold is measured, and based on the measured value, the output power of the inverter that supplies the high frequency power is adjusted, and the induction coil for the upper mold and the induction coil for the lower mold, An induction heating molding method, wherein the upper die and the lower die are independently temperature-controlled by adjusting the partial pressure of a secondary coil of an insulating transformer that electrically insulates the inverter and the inverter. Of the upper mold and the lower mold, for one of the molds whose temperature is desired to be set higher, an adjustment amount of the output power of the inverter is calculated from the difference between the measured mold temperature and the target temperature, and based on the calculated value, By adjusting the output power to make the mold temperature follow the target temperature, and calculating the amount of adjustment of the coil partial pressure from the difference between the measured mold temperature and the target temperature for the other mold whose temperature is to be set lower, 6. The induction heating molding method according to claim 5, wherein the mold temperature is made to follow a target temperature by adjusting a partial pressure of the coil based on the calculated value.

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