JP7341408B2 - Magnetic field heating molding system and magnetic field heating molding method - Google Patents

Description

The present invention relates to a magnetic field heating forming system and a magnetic field heating forming method.

Composite materials in which reinforcing fibers are impregnated with resin are known as materials that are lightweight and have high strength. Composite materials are used in aircraft, automobiles, ships, etc. One method for manufacturing composite materials is to apply a magnetic field using a magnetic field coil while applying pressure to a composite material made of reinforcing fibers impregnated with resin using a pressure head, thereby inductively heating the composite material using the magnetic field. known (see Patent Document 1).

Japanese Patent Application Publication No. 2017-193123

Conventionally, when molding a material to be molded, such as a composite material, using magnetic field heating as described in Patent Document 1, there has been a problem that it is difficult to measure the temperature of the material to be molded during molding. Ta. For example, the material to be molded during molding is in a state where the part being molded is under pressure by a pressure head, etc., so it is covered by the pressure head, etc., so infrared thermography, etc. is used. It is difficult to measure the surface temperature of the material to be molded during molding. In addition, if a thermocouple or the like is embedded in the material to be formed during molding, although it is possible to measure the temperature of the material to be formed during molding, marks from the embedded thermocouple, etc. will remain on the material to be formed, and It becomes difficult to use the material as a product.

The present invention has been made in view of the above, and is a magnetic field heating molding system and a magnetic field heating molding method that make it possible to measure the temperature of a molded material during molding without leaving any marks on the molded material. The purpose is to provide

In order to solve the above-mentioned problems and achieve the objectives, the magnetic field heating molding system includes a pressurizing device that presses the material to be molded, and a magnetic field that is applied in a direction intersecting the plane where the conductive loop is formed in the material to be molded. and a control device that controls each device, the control device controlling the temperature of the material to be molded based on the amount of change in the frequency of the current flowing through the magnetic field coil of the magnetic field applying device. It is characterized by calculating.

According to this configuration, the temperature of the material to be molded during molding is calculated based on the amount of change in the frequency of the current flowing through the magnetic field coil. Temperature can be measured. In addition, the absolute value of the frequency of the current flowing through the magnetic field coil changes depending on the shape and condition of the material to be molded, but by focusing on the amount of change in the frequency of the current flowing through the magnetic field coil, it is possible to determine the shape and condition of the material to be molded. The temperature of the material to be molded during molding can be measured regardless of the shape, condition, etc. of the material to be molded.

In this configuration, the control device determines a reference frequency that is the frequency of the current flowing through the magnetic field coil at a predetermined time, a reference temperature that is the temperature of the material to be molded at the predetermined time, and a current flowing through the magnetic field coil. It is preferable to calculate a temperature difference, which is the difference between the temperature of the material to be molded and the reference temperature, based on a frequency difference, which is the difference between the frequency of the molding material and the reference frequency. According to this configuration, the temperature difference can be accurately calculated based on the amount of change in the frequency of the current flowing through the magnetic field coil, so the temperature of the material to be molded during molding can be adjusted more accurately based on the reference temperature and the calculated temperature difference. It can be calculated accurately.

In this configuration, the predetermined time is preferably the time when magnetic field heating molding is started or the time when the frequency of the current used to calculate the temperature of the material to be molded immediately before is detected. According to this configuration, when a predetermined time is the start time of magnetic field heating forming, the temperature of the forming material during forming is determined based on the temperature of the forming material and the frequency of the current flowing through the magnetic field coil at the start of magnetic field heating forming. Therefore, the temperature of the material to be molded during molding can be calculated with high accuracy without accumulating errors. In addition, if the predetermined time is the time of detection of the frequency of the current used to calculate the temperature of the material to be molded immediately before, based on the temperature of the material to be molded and the frequency of the current flowing through the magnetic field coil at the time of the previous detection, Since the temperature of the material to be molded during molding can be calculated, the temperature of the material to be molded during molding can be calculated with high precision, sensitive to even the slightest temperature change.

Further, in these configurations, the control device may calculate the temperature difference by referring to a lookup table that compares the temperature difference based on the reference temperature, the reference frequency, and the frequency difference. preferable. According to this configuration, the temperature difference is calculated by referring to a lookup table calibrated in advance using a thermometer, so that the temperature of the material to be molded during molding can be calculated more accurately.

Further, in this configuration, it is preferable that the control device executes a calibration process to create or update the lookup table. According to this configuration, it is possible to create or update a lookup table for heating using a previously used thermometer and using a similar pressure device and magnetic field application device. It is possible to calculate the temperature of the material to be molded during molding while maintaining the accuracy of the temperature when using the previously used thermometer, in a form appropriate to the type of pressurizing device and magnetic field applying device. can.

Moreover, in these configurations, it is preferable that the control device controls the amount of current flowing through the magnetic field coil of the magnetic field application device based on the calculated temperature of the material to be molded. According to this configuration, since the temperature during magnetic field heating can be suitably controlled, it is possible to mold a material to be molded with a more preferable quality.

In addition, in order to solve the above-mentioned problems and achieve the purpose, the magnetic field heating forming method heats the material to be molded by applying a magnetic field while pressurizing the material. A current frequency detection step of detecting the frequency of the flowing current; and a temperature calculation step of calculating the temperature of the material to be molded based on the amount of change in the frequency of the current detected in the current frequency detection step. shall be.

According to this configuration, like the corresponding magnetic field heating forming system, the temperature of the material to be formed during forming is calculated based on the amount of change in the frequency of the current flowing through the magnetic field coil, so it leaves no trace on the material to be formed. It is possible to measure the temperature of the material being molded during molding. In addition, the absolute value of the frequency of the current flowing through the magnetic field coil changes depending on the shape and condition of the material to be molded, but by focusing on the amount of change in the frequency of the current flowing through the magnetic field coil, it is possible to determine the shape and condition of the material to be molded. The temperature of the material to be molded during molding can be measured regardless of the shape, condition, etc. of the material to be molded.

According to the present invention, it is possible to provide a magnetic field heating molding system and a magnetic field heating molding method that make it possible to measure the temperature of a molded material during molding without leaving any marks on the molded material.

FIG. 1 is a diagram schematically showing an example of the configuration of a magnetic field heating molding system according to an embodiment of the present invention. FIG. 2 is a functional block diagram showing a control device for a magnetic field heating molding system according to an embodiment of the present invention. FIG. 3 is a flowchart showing a magnetic field heating molding method according to an embodiment of the present invention.

Embodiments according to the present invention will be described in detail below based on the drawings. Note that the present invention is not limited to this embodiment. In addition, the components in the embodiments include those that can be easily replaced by those skilled in the art, or those that are substantially the same. Furthermore, the components described below can be combined as appropriate.

[Embodiment]
FIG. 1 is a diagram schematically showing an example of the configuration of a magnetic field heating molding system 10 according to an embodiment of the present invention. The magnetic field heating molding system 10 according to the embodiment of the present invention is a system that performs induction heating, that is, magnetic field heating, by applying a magnetic field while pressurizing the material 1 to be molded. As shown in FIG. 1, the magnetic field heating molding system 10 includes a pressure device 30, a magnetic field application device 40, and a control device 50.

In this embodiment, the material to be molded 1 is exemplified by a material molded into a flat plate shape extending horizontally along a plane. Further, in this embodiment, the material to be molded 1 is placed vertically above the flat table 22 that is perpendicular to the vertical direction and extends in the horizontal direction, and is subjected to magnetic field heating treatment by the magnetic field heating molding system 10. administered. Moreover, in this embodiment, the direction along the vertical direction in the magnetic field heating molding system 10 and the thickness direction of the material to be molded 1 correspond. Hereinafter, the lower side in the vertical direction of the material to be molded 1 will be referred to as one side, and the upper side in the vertical direction of the material to be molded 1 will be referred to as the other side. Note that the present invention is not limited to this form, and may be a form in which magnetic field heating is applied to the material 1 to be formed in any shape, such as a complicated shape with a curve, and the material 1 to be formed in any arrangement may be heated. Alternatively, it may be heated in a magnetic field.

In this embodiment, the material to be molded 1 is preferably a composite material that has electrically conductive reinforcing fibers and a resin, and in which an electrically conductive loop is formed by the reinforcing fibers. is not limited to this, and may be any material as long as it forms a conductive loop through which an induced current flows in response to a magnetic field.

The reinforcing fibers constituting the material to be molded 1 extend generally along a plane inside the material to be molded 1, but may include short reinforcing fibers arranged along the vertical direction. The reinforcing fibers constituting the material to be molded 1 are exemplified by carbon fibers in this embodiment, but are not limited to this, and may be other metal fibers.

The resin constituting the material to be molded 1 is impregnated with the reinforcing fibers constituting the material to be molded 1, and reacts through the magnetic field heating treatment included in the magnetic field heating molding method according to the embodiment of the present invention. The resin constituting the material to be molded 1 includes a thermosetting resin that undergoes a thermosetting reaction from a softened state or a semi-hardened state to a hardened state when heated, and a thermoplastic resin that undergoes a thermomelting reaction when heated. Illustrated. In the following, when a thermosetting resin and a thermoplastic resin are not distinguished, the resin constituting the material to be molded 1 is simply a reaction between the thermosetting reaction of the thermosetting resin and the thermal melting reaction of the thermoplastic resin. It is called.

In this embodiment, when the resin constituting the material to be molded 1 is a thermosetting resin, a resin including an epoxy resin is exemplified. It is preferable that the resin constituting the material 1 to be molded includes an epoxy resin, since it is even lighter and has even higher strength. In this embodiment, the resin constituting the material to be molded 1 is a thermosetting resin, and other examples include polyester resin and vinyl ester resin. In this embodiment, when the resin constituting the material to be molded 1 is a thermoplastic resin, polyamide resin, polypropylene resin, ABS (Acrylonitrile Butadiene Styrene) resin, polyether ether ketone (PEEK), polyether ketone ketone (PEKK) is used. ), and polyphenylene sulfide (PPS). However, the resin constituting the material to be molded 1 is not limited to these, and other resins may be used.

When the material to be molded 1 before the reaction of the resin constituting the material to be molded 1 is a composite material, in this embodiment, for example, it is a prepreg of the composite material. When the material 1 to be molded after the reaction of the resin constituting the material 1 to be molded is a composite material, it has light weight and high strength.

The flat table 22 is made of a material that is transparent to the magnetic field applied by the magnetic field coil 42 of the magnetic field applying device 40, that is, almost no eddy current is induced inside by the magnetic field applied by the magnetic field coil 42 of the magnetic field applying device 40, and the magnetic field The magnetic field coil 42 of the application device 40 is made of a material that hardly generates heat internally in response to the magnetic field applied. In this embodiment, the material forming the flat table 22 is preferably PEEK resin, which is transparent to a magnetic field, and has high pressure resistance and heat resistance, and ceramics.

The pressurizing device 30 is a device that pressurizes the material to be molded 1 disposed above the flat table 22 in the vertical direction. The pressurizing device 30 includes a pressurizing head 32 and a pressurizing cylinder 34, as shown in FIG.

As shown in FIG. 1, the pressure head 32 is provided facing the other side of the processing region 2, which is the region where the material to be molded 1 is subjected to magnetic field heating treatment, and is arranged to face the other side of the processing region 2, which is the region where the material to be molded 1 is subjected to magnetic field heating treatment, and It is provided vertically opposite to the magnetic field coil 42 of the magnetic field applying device 40 via 22 . The pressure head 32 presses the processing area 2 of the material to be molded 1 from the other side of the material to be molded 1 .

The pressure head 32 is made of a material that is transparent to the magnetic field applied by the magnetic field coil 42 of the magnetic field application device 40 . The material forming the pressure head 32 is preferably PEEK resin, which is a material that is transparent to the magnetic field applied by the magnetic field coil 42 of the magnetic field applying device 40 and has high pressure resistance and heat resistance, and ceramics. .

The pressure cylinder 34 is provided above the pressure head 32 in the vertical direction, and is electrically connected to the control device 50 . The pressure head 32 can move up and down in the vertical direction relative to the material to be molded 1 by controlling the pressure cylinder 34 by the control device 50, and can move up and down in the vertical direction relative to the material to be molded 1. The pressure applied downward in the vertical direction can be changed. It is preferable that the pressurizing device 30 pressurizes the processing area 2 of the material to be molded 1 at 200 kPa or more and 800 kPa or less, more preferably 300 kPa or more and 600 kPa or less, using the pressurizing head 32.

The magnetic field application device 40 is a device that magnetically heats the material to be molded 1 by applying a magnetic field to the material to be molded 1 disposed above the flat table 22 in the vertical direction. As shown in FIG. 1, the magnetic field application device 40 includes a magnetic field coil 42, a high frequency power source 44, and a current frequency detection device 46.

As shown in FIG. 1, the magnetic field coil 42 is provided facing one side of the processing area 2 of the material to be molded 1, and is connected to the pressurizing device 30 through the flat table 22 and the material to be molded 1. It is provided to face the pressure head 32 in the vertical direction. The magnetic field coil 42 applies a magnetic field to the processing region 2 of the material 1 to be molded from one side of the material 1 to be molded.

In this embodiment, the magnetic field coil 42 is exemplified in a form in which one coil is arranged, but a form in which a plurality of coils are arranged in a predetermined shape, for example, a square shape may also be used. The magnetic field coil 42 applies a magnetic field to an area equivalent to the horizontal area in which the coil is arranged. In this embodiment, it is preferable that the region to which the magnetic field coil 42 applies the magnetic field corresponds to the processing region 2 of the material to be molded 1 .

The coils included in the magnetic field coil 42 are oriented in a direction in which the central axis of the coil intersects the plane in which the material to be molded 1 extends. The magnetic field coil 42 generates a magnetic field along the direction intersecting the plane in which the material 1 to be molded extends, thereby generating a magnetic field along the direction intersecting the plane formed by the conductive loop in the material 1 to be molded. . The magnetic field coil 42 is arranged such that the vertically upper end of the magnetic field coil 42 is separated from one surface of the material to be molded 1 by a predetermined distance. An example of this predetermined distance is 1.5 cm.

It is preferable that the central axis of the coil included in the magnetic field coil 42 is oriented along the vertical direction. In this case, the magnetic field coil 42 generates a magnetic field along the direction perpendicular to the plane in which the material to be molded 1 extends, thereby generating a magnetic field along the direction perpendicular to the plane formed by the conductive loops in the material to be molded 1. to occur. The magnetic field coil 42 can efficiently induce eddy currents in this conductive loop by applying a magnetic field along a direction perpendicular to the plane formed by the conductive loop. Can generate heat. Therefore, the magnetic field coil 42 can magnetically heat the processing region 2 of the material to be molded 1 efficiently.

The high frequency power source 44 is provided electrically connected to the magnetic field coil 42 and is electrically connected to the control device 50. The high-frequency power source 44 is capable of passing a current through the magnetic field coil 42 under the control of the control device 50, and determines the amount of current, which is the magnitude of the current flowing through the magnetic field coil 42, and the amount of current flowing through the magnetic field coil 42. Frequency can be changed. The magnetic field coil 42 can apply a magnetic field vertically upward to the material to be molded 1 by controlling the high frequency power supply 44 by the control device 50, and the magnitude, frequency, etc. of the applied magnetic field can be controlled by the magnetic field coil 42. can be changed. The magnetic field application device 40 preferably applies a high frequency magnetic field of 900 kHz or more to the processing region 2 of the material to be molded 1 using the magnetic field coil 42 .

The control device 50 can control the magnitude of the magnetic field applied by the magnetic field coil 42 by the amount of current that the high frequency power supply 44 causes to flow through the magnetic field coil 42, and the frequency of the magnetic field applied by the magnetic field coil 42 can be controlled by the high frequency power supply 44. 44 can be controlled by the frequency of the current flowing through the magnetic field coil 42.

The current frequency detection device 46 is provided on a conductor that electrically connects the magnetic field coil 42 and the high-frequency power source 44, and detects whether or not current is being supplied from the high-frequency power source 44 to the magnetic field coil 42, and detects the high-frequency The amount and frequency of the current supplied from the power source 44 to the magnetic field coil 42 are detected. The current frequency detection device 46 is electrically connected to the control device 50, its operation is controlled by the control device 50, and it transmits each detected result to the control device 50.

As shown in FIG. 1, the magnetic field heating molding system 10 further includes a thermometer 24 that can be placed in and removed from the processing area 2 of the material 1 to be molded. The operation of the thermometer 24 is controlled by the control device 50, and the thermometer 24 transmits information on the detected temperature to the control device 50.

The magnetic field heating molding system 10 also includes a moving mechanism (not shown) that synchronously changes the horizontal position of the pressure head 32 with respect to the material to be molded 1 and the horizontal position of the magnetic field coil 42 with respect to the material to be molded 1. may be provided. This moving mechanism is controlled by the control device 50, and during magnetic field heating molding by the magnetic field heating molding system 10, the processing region 2, which is a region to be pressurized by the pressure head 32 and a region to which a magnetic field is applied by the magnetic field coil 42, is covered. The molding material 1 can be moved. The control device 50 can determine at any time which region of the material 1 to be molded the processing region 2 has moved.

The control device 50 is electrically connected to the pressurizing cylinder 34, the high frequency power source 44, the current frequency detection device 46, and the thermometer 24, and controls the operation of these parts. The control device 50 controls the pressure cylinder 34 to control the vertical position of the pressure head 32 relative to the material 1 to be molded and to apply pressure vertically downward to the material 1 to be molded. The magnitude of the pressure, etc. can be controlled. The control device 50 controls the magnitude of the magnetic field that the magnetic field coil 42 applies to the material 1 to be molded by controlling the high frequency power supply 44 to control the amount and frequency of the current flowing through the magnetic field coil 42. and the frequency can be controlled. Thereby, the control device 50 can control the heating temperature, temperature increase rate, heating time, etc. for heating the material to be molded 1, depending on the shape, composition, etc. of the material to be molded 1. The control device 50 can acquire information regarding each detection result of the current frequency detection device 46 from the current frequency detection device 46, and can acquire information regarding the temperature detected by the thermometer 24 from the thermometer 24.

FIG. 2 is a functional block diagram showing the control device 50 of the magnetic field heating molding system 10 according to the embodiment of the present invention. The control device 50 is an information processing device including a computer system that controls the magnetic field heating molding system 10. As shown in FIG. 2, the control device 50 includes a processing section 51, a storage section 52, and an information communication interface 53.

The processing unit 51 is a controller, and for example, uses a CPU (Central Processing Unit), an MPU (Micro Processing Unit), etc. to process various programs ( (corresponding to an example of a magnetic field heating molding program) is realized by executing a RAM (Random Access Memory) as a work area. Further, the processing unit 51 is, for example, a controller, and is realized by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). The processing unit 51 receives information input from the pressurizing cylinder 34, the high-frequency power source 44, the current frequency detection device 46, and the thermometer 24, and displays magnetic field heating on the display unit 70 electrically connected to the control device 50. An information communication interface 53 is connected to output information such as various parameters, detection results, and calculation results regarding the molding system 10.

As shown in FIG. 2, the processing section 51 is electrically connected to the storage section 52 and the information communication interface 53 so as to be able to communicate information with each other, and functions as a control section that controls each of these components. That is, the processing unit 51 functions as a control unit together with the storage unit 52, and causes the magnetic field heating molding system 10 to execute the magnetic field heating molding method according to the embodiment of the present invention.

As shown in FIG. 2, the processing section 51 includes an initial temperature acquisition section 61, a current frequency acquisition section 62, a temperature calculation section 63, a current control section 64, and a calibration section 65.

The initial temperature acquisition unit 61 controls the thermometer 24 and acquires the initial temperature detected by the thermometer 24 installed in the processing area 2 of the molding material 1 via the information communication interface 53 . Here, the initial temperature is defined as the initial temperature of the processing area 2 of the material to be formed 1 at the time of starting magnetic field heating forming, that is, when starting to flow current from the high frequency power supply 44 to the magnetic field coil 42 that magnetically heats the processing area 2 of the material 1 to be formed. refers to the temperature of

The current frequency acquisition unit 62 controls the current frequency detection device 46 to obtain various information detected by the current frequency detection device 46, that is, information on whether or not current is being supplied from the high frequency power supply 44 to the magnetic field coil 42, Information on the amount and frequency of the current supplied from the high frequency power source 44 to the magnetic field coil 42 is acquired via the information communication interface 53.

The temperature calculation unit 63 calculates the temperature of the processing region 2 of the material to be molded 1 during molding, based on the amount of change in the frequency of the current flowing through the magnetic field coil 42 of the magnetic field application device 40. Specifically, the temperature calculation unit 63 calculates a reference frequency that is the frequency of the current flowing through the magnetic field coil 42 at a predetermined time, a reference temperature that is the temperature of the processing area 2 of the material to be molded 1 at the same predetermined time, Based on the frequency difference, which is the difference between the frequency of the current flowing through the magnetic field coil 42 during molding and the reference frequency, calculate the temperature difference, which is the difference between the temperature of the processing area 2 of the molded material 1 during molding and the reference temperature. By doing so, the temperature of the processing area 2 of the material to be molded 1 during molding is calculated. It is preferable that the temperature calculation unit 63 calculates the temperature of the processing area 2 of the material 1 to be molded during molding, using a lookup table 68 to be described later.

In the magnetic field heating molding system 10 according to the embodiment, when the temperature of the processing area 2 of the material to be molded 1 during molding changes, the temperature of the magnetic field coil 42 of the magnetic field applying device 40 changes based on this temperature change. Therefore, the load impedance of the magnetic field coil 42 of the magnetic field applying device 40 changes, and according to this change in impedance, the processing unit 51 automatically executes impedance matching processing within the system, thereby adjusting the load impedance of the magnetic field applying device 40. The frequency of the current flowing through the magnetic field coil 42 is changed. In this series of steps, in the magnetic field heating molding system 10 according to the embodiment, the amount of change in the temperature of the processing area 2 of the material to be molded 1 during molding, and the change in the frequency of the current flowing through the magnetic field coil 42 of the magnetic field applying device 40 There is a certain regularity between quantities. In particular, when the amount of change in the temperature of the processing area 2 of the material to be molded 1 during molding is minute, there is a law of proportionality between the amount of change in the frequency of the current flowing through the magnetic field coil 42 of the magnetic field application device 40. have sex. Taking advantage of this law in the magnetic field heating molding system 10 according to the embodiment, the temperature calculating unit 63 calculates the temperature during molding based on the amount of change in the frequency of the current flowing through the magnetic field coil 42 of the magnetic field applying device 40 by impedance matching processing. By calculating the amount of change in temperature of the processing region 2 of the material 1 to be molded, the temperature of the processing region 2 of the material 1 to be molded during molding is calculated.

Here, the above-mentioned predetermined time is preferably the time when magnetic field heating molding is started or the time when the frequency of the current used to calculate the temperature of the processing area 2 of the material to be molded 1 immediately before is detected. When the predetermined time is the start of magnetic field heating forming, calculate the temperature of the forming material 1 during forming based on the temperature of the forming material 1 at the start of magnetic field heating forming and the frequency of the current flowing through the magnetic field coil. Therefore, the temperature calculation unit 63 performs calculation processing with a fixed reference. In addition, if the predetermined time is the time of detection of the frequency of the current used to calculate the temperature of the material to be formed 1 immediately before, the temperature of the material to be formed 1 and the frequency of the current flowing through the magnetic field coil at the time of the previous detection are used as the reference. In order to calculate the temperature of the material 1 to be molded during molding, the temperature calculation unit 63 sequentially performs calculation processing.

The current control unit 64 controls the amount of current flowing through the magnetic field coil 42 of the magnetic field application device 40 during molding, based on the temperature of the processing region 2 of the material 1 being molded that is calculated by the temperature calculation unit 63. Specifically, when the temperature calculated by the temperature calculation unit 63 is higher than a predetermined upper limit threshold in the heating temperature range during molding of the processing region 2 of the molded material 1, the current control unit 64 controls the high frequency power supply 44. By controlling , the amount of current flowing through the magnetic field coil 42 is weakened. Further, the current control unit 64 controls the high frequency power source 44 when the temperature calculated by the temperature calculation unit 63 is smaller than a predetermined lower limit threshold in the heating temperature range during molding of the processing region 2 of the molded material 1. This increases the amount of current flowing through the magnetic field coil 42.

The proofreading unit 65 executes configuration processing to create or update a lookup table 68, which will be described later. Specifically, the calibration unit 65 performs a magnetic field heating molding method executed by a magnetic field heating molding system 10 according to an embodiment of the present invention, which will be described later, with the thermometer 24 installed in the processing area 2 of the material 1 to be molded. On the other hand, instead of calculating the temperature of the processing area 2 of the material 1 to be molded during molding by the temperature calculating section 63, the initial temperature acquisition section 61 uses the thermometer 24 to process the material 1 to be molded during molding. Obtain the temperature of region 2, perform similar magnetic field heating shaping for the other parts, and create or update the lookup table 68 that contrasts the temperature difference based on the reference temperature, reference frequency, and frequency difference. do. Note that even when the above-mentioned predetermined time is the start of magnetic field heating forming, the calibration unit 65 detects the frequency of the current used to calculate the temperature of the processing area 2 of the material to be formed 1 immediately before. Even in certain cases, it is preferable to create or update lookup tables 68 corresponding to various cases.

Each part included in the processing unit 51, that is, the initial temperature acquisition unit 61, the current frequency acquisition unit 62, the temperature calculation unit 63, the current control unit 64, and the calibration unit 65, are all This is a functional unit that is realized by executing .

The storage unit 52 is realized by, for example, a semiconductor memory element such as a ROM (Read Only Memory), a RAM (Random Access Memory), or a flash memory, or a storage device such as a hard disk or an optical disk. The storage unit 52 stores and saves a lookup table 68.

The storage unit 52 stores various output processing information necessary for generating control signals for controlling each device of the magnetic field heating molding system 10 and analysis processing of received signals obtained from each device of the magnetic field heating molding system 10. Stores various necessary input processing information. The storage unit 52 also stores various input information obtained by analyzing received signals obtained from each device of the magnetic field heating molding system 10 as needed.

The lookup table 68 stored in the storage unit 52 is a model that uses a reference temperature, a reference frequency, and a frequency difference as input information, and uses a temperature difference as output information. The lookup table 68 is used by the temperature calculation unit 63 when calculating the temperature difference. The lookup table 68 is created or updated by the proofreading unit 65 as appropriate. The lookup table 68 created or updated by the calibration unit 65 in response to various cases is created using the above-mentioned certain rules, so the temperature calculation unit 63 uses the above-mentioned certain rules. This will suitably assist the calculation process. Specifically, the lookup table 68 calculates proportionality coefficients corresponding to various cases in each proportional relationship when the temperature change in the processing area 2 of the material 1 to be molded during molding is minute. 63 can be provided accurately.

The information communication interface 53 connects the processing unit 51 and each device electrically connected to the control device 50 so that they can communicate information with each other. The information communication interface 53 receives the initial temperature detected by the thermometer 24 from the thermometer 24 and transmits it to the processing unit 51 . Further, the information communication interface 53 receives various information detected by the current frequency detection device 46 from the current frequency detection device 46 and transmits it to the processing unit 51.

The information communication interface 53 receives each piece of information generated by the processing unit 51 from the processing unit 51, such as control signals for controlling the thermometer 24, the pressurizing cylinder 34, the high frequency power source 44, and the current frequency detection device 46. , are transmitted to the thermometer 24, pressurizing cylinder 34, high frequency power source 44, and current frequency detection device 46, respectively.

The information communication interface 53 also provides various information related to magnetic field heating molding generated by the processing unit 51, such as the pressure applied to the processing area 2 of the material 1 to be molded, and the high frequency power supply 44 by the current frequency detection device 46. Part or all of the information such as the amount and frequency of the flowing current, information regarding the predetermined time used by the temperature calculation unit 63 to calculate the temperature, reference temperature, reference frequency, frequency difference, and temperature difference. Information about a display image to be displayed is received from the processing unit 51 and transmitted to the display unit 70.

The operation of the magnetic field heating molding system 10 according to the embodiment will be described below. FIG. 3 is a flowchart showing a magnetic field heating molding method according to an embodiment of the present invention. Regarding the magnetic field heating molding method according to the embodiment executed by the magnetic field heating molding system 10, the initial temperature acquisition unit 61, current frequency acquisition unit 62, temperature calculation unit 63, and current control unit 64 in the processing unit 51 of the magnetic field heating molding system 10 and the detailed functions of the calibration unit 65 will be explained below.

As shown in FIG. 3, the magnetic field heating forming method according to the embodiment includes an initial information acquisition step S11, a current frequency detection step S12, a temperature calculation step S13, a current control step S14, and a heat treatment end determination step S15. , has.

The magnetic field heating forming method according to the embodiment may include a calibration step before performing the initial information acquisition step S11. The proofreading step is a step in which the proofreading unit 65 creates or updates the lookup table 68.

Specifically, in the calibration step, with the thermometer 24 installed in the processing area 2 of the material 1 to be molded, the temperature calculation unit 63 calculates the Instead of calculating the temperature of the processing region 2 of the molding material 1, the temperature of the processing region 2 of the molding material 1 during molding is acquired by the initial temperature acquisition unit 61 using the thermometer 24, and the temperature of the processing region 2 of the molding material 1 during molding is calculated. Similar magnetic field heating molding is performed for .

In the calibration step, next, the calibration unit 65 creates a look by comparing and modeling the reference temperature, reference frequency, frequency difference, and temperature difference information obtained by performing this magnetic field heating shaping. An up table 68 is created.

In the calibration step, the calibration unit 65 creates a new look-up table 68 and stores it in the storage unit 52 if the look-up table 68 based on the executed magnetic field heating molding is not yet stored in the storage unit 52. Make me remember. In the calibration step, if the lookup table 68 based on the executed magnetic field heating molding is not already stored in the storage unit 52, the calibration unit 65 uses the lookup table 68 already stored in the storage unit 52. On the other hand, the newly created lookup table 68 is overwritten and updated.

Note that the calibration unit 65 preferably creates and updates a plurality of lookup tables 68 for each configuration such as the shape and composition of the material to be molded 1 to be subjected to the magnetic field heating treatment. For example, when the material to be molded 1 is a composite material, the calibration unit 65 creates a lookup table 68 for each shape of the material to be molded 1 to be formed by magnetic field heating, and for each combination of reinforcing fibers and resin that constitute the material to be molded 1. It is preferable to create and update multiple copies.

Further, the initial temperature, which is the temperature of the processing region 2 of the material to be molded 1 at the start of magnetic field heating molding, may have a significant difference depending on whether or not magnetic field heating treatment was performed immediately before. Therefore, the calibration unit 65 separately creates and updates the lookup table 68 for the case where the magnetic field heating process has not been performed immediately before, and the lookup table 68 for the case when the magnetic field heating process has been performed immediately before. It is preferable.

Note that the calibration step is not limited to being executed immediately before the initial information acquisition step S11, but may be executed in advance, separately from the flow of the magnetic field heating forming method according to the embodiment.

The initial information acquisition step S11 includes the initial temperature, which is the temperature of the processing area 2 of the material to be molded 1 at the start of magnetic field heat forming, and the current supplied from the high frequency power supply 44 to the magnetic field coil 42 at the start of magnetic field heat forming. This step is to obtain an initial frequency that is the frequency of .

In the initial information acquisition step S11, first, the thermometer 24 is installed in the processing area 2 of the material to be molded 1, and the initial temperature acquisition unit 61 controls the thermometer 24 to The temperature detected by the installed thermometer 24 is acquired as the initial temperature, and the thermometer 24 is evacuated from the processing area 2 of the material 1 to be molded.

In the initial information acquisition step S11, the control device 50 next controls the pressure cylinder 34 to start pressurizing the processing area 2 of the molding material 1 by the pressure head 32, and controls the high frequency power source 44. Application of current to the magnetic field coil 42 is started to start magnetic field heating of the processing area 2 of the material to be molded 1 by the magnetic field coil 42, and the current frequency acquisition unit 62 controls the current frequency detection device 46 to detect the magnetic field. The frequency of the current detected by the current frequency detection device 46 at the start of thermoforming is acquired as the initial frequency.

After passing through the initial information acquisition step S11, the magnetic field heating molding process of the processing area 2 of the material to be molded 1 is started. Specifically, the processing region 2 of the material to be molded 1 that has undergone the initial information acquisition step S11 is in a pressurized state in response to the application of a magnetic field to the conductive loop in the processing region 2 of the material to be molded 1. An eddy current is induced in this conductive loop, heat is generated due to the electrical resistance of the conductive loop itself, and the magnetic field heat forming process is performed by heating due to the heat generated.

The current frequency detection step S12, the temperature calculation step S13, and the current control step S14 are performed after the magnetic field heat forming process is started through the initial information acquisition step S11, and then the magnetic field heat forming process is ended in the heat process end determination step S15, which will be described later. Until then, the process is repeatedly executed at predetermined fixed time intervals. Here, the predetermined constant time corresponds to a time interval related to temperature calculation, and can be set as appropriate.

The current frequency detection step S12 is performed after the initial information acquisition step S11, or when it is determined in the heat treatment end determination step S15 that the magnetic field heating molding process is not completed, and the current frequency detection step S12 is performed at a predetermined value after the previous current frequency detection step S12. is executed after a certain amount of time has elapsed. The current frequency detection step S12 is a step in which the current frequency acquisition unit 62 detects the frequency of the current flowing through the magnetic field coil 42 to which a magnetic field is applied. Specifically, in the current frequency detection step S12, the current frequency acquisition unit 62 controls the current frequency detection device 46 to detect the frequency of the current, and acquires the frequency of the current detected by the current frequency detection device 46.

The temperature calculation step S13 is executed after the current frequency detection step S12, and the temperature calculation unit 63 determines the processing area 2 of the material to be molded 1 based on the amount of change in the frequency of the current detected in the immediately preceding current frequency detection step S12. This step is to calculate the temperature of

Here, in the temperature calculation step S13, the temperature calculation unit 63 calculates the temperature of the processing region 2 of the material to be molded 1 based on the amount of change in the frequency of the current, using the above-described certain law. It executes processing. In the following, an example will be described in which the temperature calculation unit 63 executes calculation processing in the temperature calculation step S13 by utilizing the lookup table 68 created or updated in response to various cases by the calibration unit 65. The present invention is not limited to this, but by substituting the amount of change in the frequency of the current into the mathematical formula derived for various cases based on the above-mentioned constant law and executing the calculation process, it is possible to calculate the value of the material 1 to be molded. The temperature of the processing area 2 may also be calculated.

Specifically, in the temperature calculation step S13, first, the temperature calculation unit 63 calculates the frequency at the same predetermined time as the reference frequency, which is the frequency of the current flowing through the magnetic field coil 42 at a predetermined time, which is already stored in the storage unit 52. The reference temperature, which is the temperature of the processing area 2 of the material 1 to be molded, is acquired. In temperature calculation step S13, next, the temperature calculation unit 63 calculates a frequency difference by subtracting the reference frequency from the frequency of the current detected in the previous current frequency detection step S12. In the temperature calculation step S13, the temperature calculation unit 63 uses the lookup table 68 to process the material 1 to be molded during molding based on the acquired reference frequency and reference temperature and the calculated frequency difference. A temperature difference, which is the difference between the temperature of region 2 and the reference temperature, is calculated. In the temperature calculation step S13, the temperature calculation unit 63 further calculates the temperature of the processing area 2 of the molding material 1 during molding by adding the reference temperature to the calculated temperature difference.

Here, in the temperature calculation step S13, when the above-mentioned predetermined time is set as the start time of magnetic field heating forming, the temperature calculation unit 63 sets the reference frequency and the reference temperature as the initial The initial frequency and initial temperature acquired in the information acquisition step S11 are employed. In this case, in the temperature calculation step S13, the temperature of the processing area 2 of the material 1 to be molded during molding is calculated by performing calculation processing with a fixed reference regardless of the number of steps.

In addition, in the temperature calculation step S13, when the above-described predetermined time is the time of detecting the frequency of the current used to calculate the temperature of the processing area 2 of the material to be molded 1 immediately before, the temperature calculation unit 63 In the temperature calculation step S13, the initial frequency and initial temperature acquired in the initial information acquisition step S11 are used as the reference frequency and reference temperature, and in the second and subsequent temperature calculation steps S13, as the reference frequency and reference temperature, The current frequency acquired in the previous current frequency detection step S12 and the temperature of the processing area 2 of the molded material 1 during molding calculated in the previous temperature calculation step S13 are used. In this case, in the temperature calculation step S13, the temperature of the processing region 2 of the material 1 to be molded during molding is calculated by sequential calculation processing based on the frequency and temperature of the previous current.

In the current control step S14, the current control unit 64 causes the current to flow through the magnetic field coil 42 of the magnetic field applying device 40 during molding, based on the temperature of the processing area 2 of the material 1 being molded that is calculated in the temperature calculation step S13. This is a step of controlling the amount of current.

In the current control step S14, the current control unit 64 specifies that the temperature calculated in the temperature calculation step S13 is lower than a predetermined upper limit threshold in the heating temperature range during molding of the processing area 2 of the molding material 1. If it is large, the amount of current flowing through the magnetic field coil 42 is weakened by controlling the high frequency power supply 44. Further, in the current control step S14, the current control unit 64, if the temperature calculated in the temperature calculation step S13 is smaller than the lower limit threshold in the predetermined heating temperature range during molding of the processing region 2 of the molding material 1, By controlling the high frequency power source 44, the amount of current flowing through the magnetic field coil 42 is increased.

The heat treatment completion determination step S15 is a step that is executed every time a series of current frequency detection steps S12, temperature calculation steps S13, and current control steps S14 are executed, and is a step that is executed every time a series of current frequency detection steps S12, temperature calculation steps S13, and current control steps S14 are executed. This is a step of determining whether or not to end the magnetic field heating molding process for one treatment area 2 .

Specifically, in the heat treatment completion determination step S15, if the control device 50 has not received an input to terminate the magnetic field heat forming process of the treatment area 2 of the material to be molded 1, the treatment area of the material to be molded 1 is It is determined that the magnetic field heating molding process No. 2 is to be continued (No in the heating process end determination step S15), and the process of the magnetic field heating molding method according to the embodiment is returned to the current frequency detection step S12.

In the heat treatment completion determination step S15, if the control device 50 has received an input to terminate the magnetic field heating molding process in the treatment area 2 of the material 1 to be molded, the magnetic field in the treatment area 2 of the material 1 to be molded is It is determined that the heat forming process is to be ended (Yes in the heat process end determination step S15), and the process of the magnetic field heat forming method according to the embodiment is ended.

When the magnetic field heating molding process of the processing area 2 of the molding material 1 is to be completed through the heating process end determination step S15, the high frequency power source 44 is controlled to end the application of current to the magnetic field coil 42, and the pressurizing cylinder 34 is stopped. The pressurization of the processing area 2 of the material to be molded 1 by the pressure head 32 is finished under control, and the material to be molded 1 that has been subjected to the magnetic field heating molding process is taken out from the magnetic field heating molding system 10.

Since the magnetic field heating molding system 10 according to the embodiment and the magnetic field heating molding method according to the embodiment using the magnetic field heating molding system 10 have the above configuration, based on the amount of change in the frequency of the current flowing through the magnetic field coil 42, Since the temperature of the material 1 to be molded during molding is calculated, the temperature of the material 1 to be molded during molding can be measured without leaving any marks on the material 1 to be molded. Further, in the magnetic field heating forming system 10 according to the embodiment and the magnetic field heating forming method according to the embodiment using the magnetic field heating forming system 10, the absolute value of the frequency of the current flowing through the magnetic field coil 42 is determined by the shape and state of the material 1 to be molded. However, by focusing on the amount of change in the frequency of the current flowing through the magnetic field coil 42, it is possible to suitably remove the portion caused by the shape or condition of the material 1 to be formed. The temperature of the material 1 to be molded during molding can be measured regardless of its shape or condition.

The magnetic field heating molding system 10 according to the embodiment and the magnetic field heating molding method according to the embodiment using the magnetic field heating molding system 10 are such that the control device 50 sets a reference frequency, which is the frequency of the current flowing through the magnetic field coil 42 at a predetermined time, and a predetermined frequency. Based on the reference temperature, which is the temperature of the material to be formed 1 at the time of , and the frequency difference, which is the difference between the frequency of the current flowing through the magnetic field coil 42 and the reference frequency, Calculate a certain temperature difference. Therefore, the magnetic field heating forming system 10 according to the embodiment and the magnetic field heating forming method according to the embodiment using the magnetic field heating forming system 10 can accurately calculate the temperature difference based on the amount of change in the frequency of the current flowing through the magnetic field coil 42. Therefore, the temperature of the material 1 to be molded during molding can be calculated more accurately based on the reference temperature and the calculated temperature difference.

The magnetic field heating forming system 10 according to the embodiment and the magnetic field heating forming method according to the embodiment using the magnetic field heating forming system 10 include calculation of the temperature of the material 1 to be formed at a predetermined time at the start of magnetic field heating forming or immediately before. When detecting the frequency of the current used for. Therefore, in the magnetic field heating forming system 10 according to the embodiment and the magnetic field heating forming method according to the embodiment using the magnetic field heating forming system 10, when the predetermined time is the start time of the magnetic field heating forming, Since the temperature of the material 1 to be molded during molding can be calculated based on the temperature of the material 1 to be molded and the frequency of the current flowing through the magnetic field coil 42, the temperature of the material 1 to be molded during molding can be calculated with high accuracy without accumulating errors. The temperature of the molding material 1 can be calculated. Further, the magnetic field heating forming system 10 according to the embodiment and the magnetic field heating forming method according to the embodiment using the magnetic field heating forming system 10 detect the frequency of the current used to calculate the temperature of the molded material 1 immediately before a predetermined time. In the case of a slight temperature change, the temperature of the material to be formed 1 during molding can be calculated based on the temperature of the material to be formed 1 at the time of the previous detection and the frequency of the current flowing through the magnetic field coil 42. The temperature of the material 1 to be molded during molding can be calculated with high accuracy. In addition, in the magnetic field heating forming system 10 according to the embodiment and the magnetic field heating forming method according to the embodiment using the magnetic field heating forming system 10, both modes regarding a predetermined time can be appropriately combined, and in this case, more accurate molding can be performed. It is possible to calculate the temperature of the material 1 to be molded.

In the magnetic field heating molding system 10 according to the embodiment and the magnetic field heating molding method according to the embodiment using the magnetic field heating molding system 10, the control device 50 further contrasts the temperature difference based on the reference temperature, the reference frequency, and the frequency difference. The temperature difference is calculated by referring to the lookup table 68. Therefore, the magnetic field heating molding system 10 according to the embodiment and the magnetic field heating molding method according to the embodiment using the magnetic field heating molding system 10 calculate the temperature difference by referring to the lookup table 68 calibrated in advance using the thermometer 24. Therefore, the temperature of the material 1 to be molded during molding can be calculated more accurately.

In the magnetic field heating molding system 10 according to the embodiment and the magnetic field heating molding method according to the embodiment using the magnetic field heating molding system 10, the control device 50 further performs a calibration process to create or update the lookup table 68. Therefore, the magnetic field heating molding system 10 according to the embodiment and the magnetic field heating molding method according to the embodiment using the magnetic field heating molding system 10 use the previously used thermometer 24, and the same pressure device 30 and Since the lookup table 68 can be created or updated for the case of heating using the magnetic field application device 40, the previously used The temperature of the material 1 to be molded during molding can be calculated while maintaining the accuracy of the temperature when using the thermometer 24.

Further, in the magnetic field heating forming system 10 according to the embodiment and the magnetic field heating forming method according to the embodiment using the magnetic field heating forming system 10, the control device 50 controls the magnetic field applying device 40 based on the calculated temperature of the molding material 1. The amount of current flowing through the magnetic field coil 42 is controlled. Therefore, the magnetic field heating molding system 10 according to the embodiment and the magnetic field heating molding method according to the embodiment using the magnetic field heating molding system 10 can further suitably control the temperature during magnetic field heating, so that the molded product can be molded with more desirable quality. Material 1 can be molded.

1 Material to be molded 2 Processing area 10 Magnetic field heating molding system 22 Flat table 24 Thermometer 30 Pressure device 32 Pressure head 34 Pressure cylinder 40 Magnetic field application device 42 Magnetic field coil 44 High frequency power supply 46 Current frequency detection device 50 Control device 51 Processing Section 52 Storage section 53 Information communication interface 61 Initial temperature acquisition section 62 Current frequency acquisition section 63 Temperature calculation section 64 Current control section 65 Calibration section 68 Lookup table 70 Display section

Claims (5)

a pressurizing device that pressurizes the material to be molded;
a magnetic field applying device that applies a magnetic field in a direction intersecting a plane in which a conductive loop is formed in the material to be molded;
A control device for controlling each device,
The control device calculates the temperature of the material to be molded based on the amount of change in the frequency of the current flowing through the magnetic field coil of the magnetic field application device,
A reference frequency that is the frequency of the current flowing through the magnetic field coil when detecting the frequency of the current used to calculate the temperature of the material to be molded immediately before, and a frequency of the current used to calculate the temperature of the material to be molded immediately before. The temperature of the material to be molded and the reference temperature are determined based on the reference temperature, which is the temperature of the material to be molded at the time of detection, and the frequency difference, which is the difference between the frequency of the current flowing through the magnetic field coil and the reference frequency. A magnetic field heating molding system characterized by calculating a temperature difference that is a difference between the reference temperature and the temperature difference, and sequentially calculating the temperature of the material to be molded based on the reference temperature and the temperature difference. The control device calculates the temperature difference by referring to a lookup table that compares the temperature difference based on the reference temperature, the reference frequency, and the frequency difference . The magnetic field heating forming system described. The magnetic field heating molding system according to claim 2 , wherein the control device executes a calibration process to create or update the lookup table. 4. The control device controls the amount of current flowing through the magnetic field coil of the magnetic field application device based on the calculated temperature of the material to be molded. magnetic field heating molding system. In the magnetic field heating molding method, which heats the material to be molded by applying a magnetic field while pressurizing it,
a current frequency detection step of detecting the frequency of a current flowing through a magnetic field coil that applies the magnetic field;
This is a step of calculating the temperature of the material to be molded based on the amount of change in the frequency of the current detected in the current frequency detection step, and when detecting the frequency of the current used to calculate the temperature of the material to be molded immediately before. a reference frequency that is the frequency of the current flowing through the magnetic field coil; a reference temperature that is the temperature of the material to be molded at the time of detecting the frequency of the current used to calculate the temperature of the material to be molded immediately before; A temperature difference, which is the difference between the temperature of the material to be molded and the reference temperature, is calculated based on the frequency difference, which is the difference between the frequency of the current flowing through the a temperature calculation step of sequentially calculating the temperature of the material to be molded based on ;
A magnetic field heating forming method characterized by having the following.

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