JP2018055940A - Microwave device and heat treatment system including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microwave device capable of acquiring and outputting information useful when determining the operating conditions.SOLUTION: A microwave device 100 includes a cavity resonator 30 and a microwave generator 10 capable of sweeping the frequency in a predetermined sweeping range, and can perform heat treatment of a processed object in the cavity resonator 30. The microwave device 100 includes at least one of a first power monitor 50 for measuring the electromagnetic field intensity in the cavity resonator 30, and a second power monitor 60 for measuring the electromagnetic field intensity of reflection wave, and a control section (output section) 70 for sequentially storing the measurement results of at least one of the first and second power monitors 50, 60 which change according to frequency sweep, and outputting at least one of a first signal S10 indicating frequency responce characteristics of the electromagnetic field intensity in the cavity resonator 30 within the sweep range, and a second signal S20 indicating frequency responce characteristics of the electromagnetic field intensity of reflection wave within the sweep range.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a microwave device that irradiates a microwave and performs a treatment such as heating and chemical reaction promotion on a substance.

  In recent years, it has been found that microwave high-frequency energy promotes chemical reactions of substances, and in the fields of biochemistry and other industries, science, and medicine, there is an interest in devices using microwaves (microwave devices). It is growing. As described above, an ISM band (Industrial, Scientific & Medical radio bands) is allocated as a microwave frequency band used as a high-frequency energy source. The frequency width of the ISM band is narrow, for example, about 4% of the center frequency in the most commonly used 2,450 MHz band. That is, the frequency of the microwave used in the microwave device must be within a narrow ISM band.

  As such a microwave device for promoting chemical reaction and heating, the one described in Patent Document 1 is known. The microwave device described in Patent Document 1 includes a cavity resonator, introduces microwaves into the cavity in the cavity resonator, and resonates to generate a single-mode electric field. The to-be-processed liquid which distribute | circulates the inside of the arrange | positioned distribution pipe is heat-processed. In this microwave device, the liquid to be treated is efficiently heat-treated at the time of resonance of the cavity resonator (that is, when the oscillation frequency and the resonance frequency of the cavity resonator are appropriately tuned). can do.

JP 2012-75996 A

  By the way, in the microwave apparatus described in Patent Document 1, various types of liquids to be processed ranging from liquids having a low dielectric constant to liquids having a high dielectric constant are processed. The dielectric constant of the liquid to be treated is generally defined by a complex number, and the real part is an amount related to the resonance frequency, and the imaginary part is an amount related to heat generation or loss. The imaginary part is generally called a dielectric loss factor. Hereinafter, the real part of the dielectric constant defined by a complex number is simply referred to as a dielectric constant for convenience.

Specifically, the dielectric constant of the liquid to be treated is a parameter that affects the resonance frequency of the cavity resonator and changes according to the temperature change of the liquid to be treated. The resonance frequency of a cavity resonator is basically determined by its structure and dimensions, but the influence of the dielectric characteristics of the flow pipe itself disposed in the cavity and the liquid to be treated flowing through the flow pipe itself Influenced by dielectric properties. Therefore, the actual resonance frequency of the cavity resonator is determined not only based on the structure and dimensions of the cavity resonator but also on the dielectric properties of the liquid to be treated and the flow pipe, and changes depending on the type of liquid to be treated and the temperature change. It is a fluid parameter. For example, when the temperature of the liquid to be processed rises, the dielectric constant of the liquid to be processed generally decreases, and as a result, the actual resonance frequency of the cavity resonator is determined by the structure and dimensions of the cavity resonator. It rises above the resonance frequency.
On the other hand, the dielectric loss factor of the liquid to be processed is a fluid parameter that affects the reflection of the microwave from the cavity resonator and changes according to the temperature change of the liquid to be processed. If the dielectric loss factor is at an appropriate level, it is designed to suppress the reflection of the microwave from the cavity resonator. However, in general, when the dielectric loss factor decreases (that is, it becomes difficult to absorb microwaves), the reflection from the cavity resonator increases, and the ratio of the microwave power that can be introduced into the cavity resonator becomes smaller. descend.

  Here, in the microwave device described in Patent Document 1, in order to treat the liquid to be processed as efficiently as possible using microwaves having a frequency within the ISM band, the oscillation frequency and the cavity resonator are processed. It is necessary to satisfy two requirements of appropriately tuning the actual resonance frequency and minimizing (matching) the reflection of the microwave from the cavity resonator.

  However, in the microwave device described in Patent Document 1, the actual resonant frequency of the cavity resonator and the dielectric loss factor of the liquid to be treated related to reflection are fluid parameters that change according to temperature changes. The contents of the two requirements also change according to the temperature change. For this reason, an operator of the microwave device described in Patent Document 1 may be forced to place an excessive burden when setting or adjusting the operating conditions of the device. In particular, when treating a liquid to be treated that has a large change in dielectric characteristics in response to changes in temperature, such as ethanol, the operator must spend time by trial and error when adjusting the operating conditions. The current situation is that it is being dealt with over time, and that ingenuity is required.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a microwave device that can acquire and output useful information when determining operating conditions.

  According to one aspect of the present invention, a microwave device includes a cavity resonator that resonates a microwave, and a microwave generator that generates the microwave and can sweep the frequency within a predetermined sweep range, The object to be processed can be heat-treated in the cavity resonator. The microwave device includes a first measurement unit that measures an electromagnetic field intensity in the cavity resonator, and an electromagnetic field intensity of a reflected wave reflected from the cavity resonator toward the microwave generator. Including at least one of the second measurement units to be measured, and sequentially storing measurement results of at least one of the first measurement unit and the second measurement unit respectively changing according to the frequency sweep of the microwave, and the sweep range At least one of a first signal indicating a frequency response characteristic of the electromagnetic field intensity in the cavity resonator and a second signal indicating a frequency response characteristic of the electromagnetic field intensity of the reflected wave in the sweep range; Includes output.

According to the microwave device according to the one aspect, the output unit sequentially stores at least one measurement result of the first measurement unit and the second measurement unit that change in accordance with the frequency sweep of the microwave, and in the sweep range. At least one of the first signal indicating the frequency response characteristic of the electromagnetic field intensity in the cavity resonator and the second signal indicating the frequency response characteristic of the electromagnetic field intensity of the reflected wave in the sweep range can be output. Since the frequency sweep of the microwave can be performed in a very short time, the operator can, for example, stop the microwave generator while gradually raising the temperature while raising the temperature with the microwave generator or gradually lower the temperature. However, when the predetermined temperature is reached, at least one of the first signal data and the second signal data can be obtained. When the temperature of the object to be processed changes, at least one of the first signal data and the second signal data can be obtained for each temperature corresponding to the change. Therefore, for example, even when a liquid to be processed having a large change in dielectric characteristics in response to a temperature change is a processing target, the operator uses the acquired data group for each temperature to obtain the above two requirements (that is, It is possible to accurately recognize (monitor) the state of the device at each temperature with respect to at least one of the requirements on tuning and matching), and appropriately determine the operating conditions based on the obtained information. Can be adjusted.
In this way, according to the microwave device, it is possible to acquire and output useful information when determining operating conditions.

1 is a schematic configuration diagram of a microwave device according to an embodiment of the present invention. It is the schematic of the cavity resonator of the said microwave apparatus, (A) is the front view seen from the same side as FIG. 1, (B) is a left side view, (C) is a top view. It is a conceptual diagram for demonstrating an example of the measurement result by the 1st power monitor and the 2nd power monitor of the said microwave apparatus. It is a conceptual diagram for demonstrating the calculation method of Q value of the said cavity resonator. It is the figure which showed an example of the display content of the display part of the said microwave apparatus. It is the figure which showed another example of the display content of the said display part. It is the figure which showed another example of the display content of the said display part. It is the figure which showed the state by which the dielectric piece was arrange | positioned in the said cavity resonator. It is a conceptual diagram for demonstrating the modification of the dielectric piece arrange | positioned in the said cavity resonator. It is a conceptual diagram for demonstrating the position adjustment of the dielectric piece shown in FIG. It is a conceptual diagram for demonstrating the modification of the flow pipe arrange | positioned in the said cavity resonator. FIG. 12 is a conceptual diagram for explaining an example in which another dielectric piece is arranged in the modification shown in FIG. 11. It is a conceptual diagram for demonstrating another modification of the flow pipe arrange | positioned in the said cavity resonator. It is the figure seen from the arrow X2 direction shown in FIG.

Embodiments of the present invention will be described below with reference to the drawings.
In FIG. 1, the schematic block diagram of one Embodiment of the microwave apparatus based on this invention is shown.
In FIG. 1, the microwave device 100 includes a microwave generator 10, a waveguide 20, a cavity resonator 30, a flow tube 40, a first power monitor 50, a second power monitor 60, This is a flow type apparatus that includes a control unit 70 and a display unit 80 and is capable of heat-treating a liquid to be processed as an appropriate object to be processed in the cavity resonator 30. The microwave device 100 is configured such that the microwave generator 10 is connected to the waveguide 20 via a coaxial cable or the like, the waveguide 20 is assembled to the cavity resonator 30, and is controlled by the control unit 70. ing.

  The microwave generator 10 is configured to generate a microwave and to sweep the frequency (oscillation frequency f) within a predetermined sweep range. The microwave generator 10 includes, for example, a variable frequency oscillator 11, a variable attenuator 12, and an amplifier 13. The variable frequency oscillator 11 outputs microwaves, and includes, for example, a voltage controlled oscillator (VCO). The variable frequency oscillator 11 is configured to be able to sweep the oscillation frequency f within a sweep range of 2.4 GHz to 2.5 GHz which is an ISM frequency band by changing an applied voltage. The variable attenuator 12 variably attenuates the microwave power input from the variable frequency oscillator 11. The amplifier 13 amplifies the microwave power input from the variable attenuator 12. The control unit 70 controls the oscillation frequency f and power of the microwave oscillated by the variable frequency oscillator 11 and the attenuation factor of the variable attenuator 12. Moreover, although the microwave generator 10 is normally configured to be able to sweep in the ISM frequency band, it may be configured to be able to sweep in a slightly wider range than the ISM frequency band as necessary.

  The waveguide 20 guides the microwave output from the microwave generator 10 and introduces it to the cavity resonator 30. Specifically, the microwave from the microwave generator 10 is sent to the coaxial waveguide converter 21 via the isolator 14, the matching unit 15, and the directional coupler 16 connected by a coaxial cable. Then, the microwave guided by the waveguide 20 through the coaxial waveguide converter 21 is introduced into the cavity resonator 30 through an iris 31 described later. Here, for example, when the dielectric loss rate of the liquid to be processed flowing through the cavity resonator 30 is inappropriate and the matching is not achieved, the reflection of the microwave from the cavity resonator 30 increases. Since this reflected wave may break the microwave generator 10 when returning to the microwave generator 10, it is suppressed by the matching unit 15 to be as small as possible. In this embodiment, the reflected wave is absorbed by the non-reflection terminator 17 by the action of the isolator 14.

  The cavity resonator 30 includes an iris 31 for introducing the microwave from the microwave generator 10 and an irradiation chamber 32 as a cavity for resonating the introduced microwave, and resonance of the microwave. This generates a single-mode electric field in the irradiation chamber 32. Specifically, as shown in FIGS. 2A to 2C, the cavity resonator 30 includes an upper wall 33, a bottom wall 34, and side walls 35, 36, 37, and 38. . The upper wall 33 and the bottom wall 34 face each other and are square. The side walls 35, 36, 37, and 38 are each rectangular, and the short sides thereof are fixed to the sides of the upper wall 33 and the bottom wall 34 with bolts or the like (not shown). In this way, a rectangular columnar (regular quadratic columnar) cavity irradiation chamber 32 is formed in the casing formed by assembling the upper wall 33, the bottom wall 34, and the side walls 35, 36, 37, 38. In the case of the present embodiment, the side wall 35 on the waveguide 20 side is connected to the flange 22 of the waveguide 20 to connect the waveguide 20 as shown in FIGS. 2 (B) and 2 (C). The area has been expanded in correspondence.

  The iris 31 is a coupling slit for introducing a microwave into the irradiation chamber 32, and is opened as a rectangular opening at the central portion of the side wall 35 that forms the side surface of the irradiation chamber, as shown in FIG. This rectangular opening is rectangular, and its long axis extends parallel to the center axis C of the irradiation chamber 32 that connects the centers of the upper surface and the bottom surface of the irradiation chamber 32, that is, the centers of the upper wall 33 and the bottom wall 34. .

  The microwave introduced into the irradiation chamber 32 of the rectangular columnar cavity through the iris 31 generates a single mode electric field in a direction parallel to the central axis C at the time of resonance. Strictly speaking, if nothing is contained in the cavity resonator 30, the electromagnetic field of the TM110 mode is excited. Therefore, an electromagnetic field having a distribution approximately in accordance with the TM110 mode electromagnetic field distribution is generated in the irradiation chamber 32. For example, in the case of a microwave having a frequency of 2.45 GHz that is generally used in heating or the like, a single mode electric field can be generated between the side wall 35 and the side wall 37 when there is nothing in the irradiation chamber 32. The distance L and the distance L between the side wall 36 and the side wall 38 (see FIG. 2C) are each designed to be 86.5 mm. However, in reality, since there is a liquid to be processed as a dielectric and a flow pipe 40 through which the liquid to be processed flows in the irradiation chamber 32, the resonance frequency f0 of the cavity resonator 30 is affected by the influence. Go down. Therefore, the distance L between the side walls is set to be smaller than the dimension when empty (86.5 m in this example), and the resonance frequency f0 is affected by the liquid to be processed in the irradiation chamber 32 and the flow pipe 40. It is designed to have a generally targeted resonance frequency when it is received and lowered. Further, the distance H (see FIG. 2A) between the upper wall 33 and the bottom wall 34 in the irradiation chamber 32, that is, the height of the quadrangular prism may be designed with a necessary length as appropriate.

  The iris 31 is involved in setting the electromagnetic field excited in the irradiation chamber 32 only to the scheduled single mode (TM110). In the iris 31 shown in FIG. 2B, a microwave current flows in the long side (side edge) in a direction parallel to the central axis C, and the magnetic field surrounding the central axis C due to this current An electric field parallel to the central axis C is generated. An optimum value of the width of the iris 31 (direction orthogonal to the central axis C) can be obtained by simulation and experiment.

  In addition, at the central portion of the upper wall 33 and the bottom wall 34, bottomed cylindrical members 39 and 39 ′ that support both ends of the flow pipe 40 without letting the microwave introduced into the irradiation chamber 32 escape to the outside. Each is arranged. The cylindrical members 39, 39 ′ support the both ends of the flow pipe 40 by positioning the flow pipe 40 so that the central axis C of the irradiation chamber 32 and the axis line of the flow pipe 40 substantially coincide with each other, and the irradiation. Microwave leakage from the chamber 32 to the outside is prevented.

  The distribution pipe 40 is a pipe that is disposed so as to penetrate the cavity resonator 30 and distributes a liquid to be processed as an object to be processed. In the present embodiment, the flow pipe 40 is made of, for example, a quartz glass snake pipe extending spirally. The circulation pipe 40 is arranged so that the spiral center thereof coincides with the central axis C of the irradiation chamber 32. Further, both end portions of the flow tube 40 extend linearly along the central axis C of the irradiation chamber 32. The liquid to be processed, which is pumped by a pump (not shown) that pumps the liquid to be processed, flows from one end side (the lower side in the figure) to the other end side (the upper side in the figure) of the flow pipe 40. In the middle, heat treatment is performed by microwaves.

  The first power monitor 50 measures the electromagnetic field strength (electric field or magnetic field strength) in the cavity resonator 30, and is attached to the side wall 37 of the cavity resonator 30, for example. A signal S 1 indicating the measurement result of the electromagnetic field intensity measured by the first power monitor 50 is input to the control unit 70. In the present embodiment, the first power monitor 50 corresponds to a “first measurement unit” according to the present invention.

  The second power monitor 60 measures the electromagnetic field intensity of the reflected wave reflected from the cavity resonator 30 toward the microwave generator 10, and obtains a reflected signal from the directional coupler 16. Yes. A signal S 2 indicating the measurement result of the electromagnetic field intensity measured by the second power monitor 60 is input to the control unit 70. In the present embodiment, the second power monitor 60 corresponds to a “second measurement unit” according to the present invention.

  Here, an example of a measurement result by the first power monitor 50 and the second power monitor 60 will be described with reference to FIG.

  FIG. 3 shows each case where the oscillation frequency f is swept within a sweep range of 2.4 GHz to 2.5 GHz when a predetermined treatment liquid is irradiated with microwaves in the cavity resonator 30. The change state of the measurement results of the power monitors 50 and 60 is shown. The lower diagram shows an example of the frequency response characteristic of the electromagnetic field intensity in the cavity resonator 30 in the sweep range, and the upper diagram shows the sky response in the sweep range. An example of the frequency response characteristic of the electromagnetic field intensity of the reflected wave from the trunk resonator 30 is shown. In FIG. 3, the horizontal axis represents the oscillation frequency f of the microwave generator 10, and the vertical axis represents the measurement results (signals S1, S2) of the electromagnetic field strength from the power monitors 50, 60. Since sweeping of the oscillation frequency f in the sweep range can be completed instantaneously, FIG. 3 shows frequency response characteristics when the temperature of the predetermined liquid to be treated is a specific value (for example, room temperature). . In the case of this predetermined liquid to be treated, for example, at room temperature, the electromagnetic field strength (signal S1) in the cavity resonator 30 is maximized at a predetermined frequency position, and the electromagnetic field strength (signal S2) of the reflected wave is predetermined. Minimized in frequency position. That is, the signal S1 changes so as to have a clear maximum value, and the signal S2 changes so as to have a clear minimum value. The frequency f of the maximum value (that is, the peak of the mountain) of the signal S1 is the resonance frequency f0 of the cavity resonator 30. Therefore, the liquid to be treated can be processed efficiently by introducing a microwave having an oscillation frequency f that matches the resonance frequency f0 into the cavity resonator 30 for tuning. Also, as shown in FIG. 3, generally, the frequency f of the minimum value (that is, the valley bottom) of the signal S2 and the frequency f of the peak of the signal S1 are substantially the same. Therefore, it can be said that the frequency f of the valley bottom of the signal S2 is the resonance frequency f0 of the cavity resonator 30. Therefore, if the oscillation frequency f and the resonance frequency f0 are appropriately tuned, the liquid to be treated can be processed efficiently. As described above, in the state where the signal S1 having the clear maximum value and the signal S2 having the clear minimum value are obtained, the tuning of the oscillation frequency f and the resonance frequency f0 is performed by the control unit 70 as described later. It can be done easily. In general, when the temperature of the liquid to be processed increases, the dielectric constant of the liquid to be processed decreases, and as a result, the actual resonance frequency f0 of the cavity resonator 30 increases. However, as shown in FIG. If the signal has a clear maximum value and the signal S2 has a clear minimum value, the heating process can be performed following the actual resonance frequency f0 changed by the control unit.

  Returning to FIG. 1, the control unit 70 controls the operation of the microwave generator 10, for example. For example, a signal S1 from the first power monitor 50 is input to the control unit 70, and a measurement result of the temperature of the liquid to be processed measured by a temperature sensor (not shown) is input to perform an optimal heating process. The operation of the microwave generator 10 is controlled as shown in FIG. The temperature of the liquid to be treated that circulates in the circulation pipe 40 shows a distribution that gradually increases from upstream to downstream due to microwave irradiation. In the initial operation stage immediately after the start of microwave irradiation, the average temperature of the liquid to be processed in the entire flow pipe 40 and the temperature of the liquid to be processed on the downstream side gradually increase. In the present embodiment, the temperature sensor is disposed so as to be able to measure the temperature of the liquid to be processed flowing through the downstream portion (the upper portion in FIG. 1) of the flow pipe 40 in the cavity resonator 30 as a representative temperature. And

  More specifically, when an operation for starting microwave irradiation is performed by the operator, the control unit 70 starts microwave output by the microwave generator 10 and executes a frequency control process. In the frequency control process, for example, the microwave oscillation frequency f output from the microwave generator 10 is tuned to the resonance frequency f0 of the cavity resonator 30 based on the signal S1 from the first power monitor 50 on the upper side. This is a control process. The controller 70 instantaneously sweeps the oscillation frequency f at a predetermined step size in the sweep range by changing the voltage applied to the variable frequency oscillator 11 at a predetermined step size. The voltage step size can be changed as appropriate. Therefore, the step size of the oscillation frequency f can be changed according to the step size of the voltage. Then, the control unit 70 detects the oscillation frequency f where the intensity of the signal S1 is the highest in the sweep range as the actual resonance frequency f0 of the cavity resonator 30, and oscillates the resonance frequency f0. By controlling the voltage applied to the variable frequency oscillator 11, tuning control of the oscillation frequency f and the resonance frequency f0 is performed. At this time, the control unit 70 may output a microwave with a minimum weak power within a range in which measurement by the first power monitor 50 is not hindered. By weakening the output power of the microwave introduced into the irradiation chamber 32, it is possible to suppress the influence that can be given to the liquid to be treated during the execution of the frequency control process.

  The controller 70 executes a power control process for controlling the power of the microwave following the tuning by the frequency control process. The power control process controls the variable attenuator 12 of the microwave generator 10 according to the conditions initially set by the operator based on the type of liquid to be processed, the heating target temperature, and the like before starting the microwave irradiation. This is the process of controlling power. In the power control process, the control unit 70 adjusts the attenuation rate of the variable attenuator 12 according to, for example, a measurement result of a power monitor (not shown) incorporated in the microwave generator 10 to thereby generate a microwave. The power of the microwave output from the generator 10 is adjusted.

  For example, when an operation to start microwave irradiation is performed, the control unit 70 first executes the frequency control process, then executes the power control process, and performs frequency control at regular intervals during the execution of the power control process. By interrupting and executing the process, the operation of the heat treatment for the liquid to be processed is performed. In the frequency control process, the control unit 70 controls the variable attenuator 12 to output a microwave with the above-described weak power, and controls the variable frequency oscillator 11 to achieve frequency tuning. That is, in the present embodiment, the frequency control process and the power control process correspond to a “processing mode for heat-treating a liquid to be processed” according to the present invention. In the present embodiment, the oscillation frequency f in the processing mode can be appropriately set to a fixed value by the operator. Further, it is configured such that an operator can appropriately adjust conditions initially set for the power control process in the processing mode. In other words, the processing mode can be executed based on the operating conditions adjusted by the operator.

  Further, in the present embodiment, the control unit 70 sequentially stores data of measurement results (signal S1 and signal S2) of the first power monitor 50 and the second power monitor 60 that change according to the frequency sweep of the microwave, respectively. Built-in memory. Then, the control unit 70 outputs the first signal S10 indicating the frequency response characteristic of the electromagnetic field intensity in the cavity resonator 30 in the sweep range of the oscillation frequency f, and from the cavity resonator 30 in the sweep range. The second signal S20 indicating the frequency response characteristic of the electromagnetic field intensity of the reflected wave can be output. Thus, the control unit 70 is configured to execute a measurement mode in which the microwave oscillation frequency f is swept within the sweep range, and the first signal S10 and the second signal S20 are acquired and output.

  Specifically, in the memory of the control unit 70, for example, each data of the signal S1 and the signal S2 is associated with the oscillation frequency f when the signal S1 and the signal S2 are obtained, for each oscillation frequency f. It is remembered. The first signal S10 is composed of a data table in which the signal S1 and the oscillation frequency f are stored in the memory corresponding to each oscillation frequency f. Similarly, the second signal S20 is composed of a data table in which the signal S2 and the oscillation frequency f are stored in the memory corresponding to each oscillation frequency f. In the present embodiment, the control unit 70 outputs the first signal S10 and the second signal S20 to the display unit 80. In the present embodiment, the control unit 70 corresponds to an “output unit” according to the present invention, and has a function of an “output unit” in addition to a function of controlling the operation of the microwave generator 10.

  In the present embodiment, the control unit 70 acquires the first signal S10 and the second signal S20 while sweeping the processing mode for heating the liquid to be processed and the oscillation frequency f of the microwave within the sweep range. A changeover switch (not shown) for switching the operation mode of the apparatus between the measurement mode to be output is provided. For example, when the changeover switch is operated by an operator in the processing mode, the control unit 70 instantaneously switches the operation mode of the apparatus to the measurement mode and causes the measurement mode operation to be executed. This measurement mode operation can be completed instantaneously. When the changeover switch is operated again after the measurement mode operation is completed, the operation mode is switched to the processing mode, and the processing mode is executed.

  The display unit 80 displays the frequency response characteristic of the electromagnetic field intensity of the cavity resonator 30 and the frequency response characteristic of the electromagnetic field intensity of the reflected wave based on the first signal S10 and the second signal S20. For example, it consists of a personal computer incorporated in the apparatus.

Here, for example, when the type of the liquid to be treated changes, the resonance frequency f0 changes, and the shape and height of the peak of the first signal S10 and the shape and depth of the valley of the second signal S20 change. In particular, when the microwave of the liquid to be processed is largely absorbed, the mountain of the first signal S10 becomes a gentle hill, its height decreases, and the valley of the second signal S20 gradually falls. It shows a tendency that the depth becomes shallow. Sometimes mountains and valleys are almost invisible. When this absorption is large, it is expressed that the Q value of the cavity resonator 30 is low. This Q value can be easily calculated based on the first signal S10, for example. Specifically, as shown in FIG. 4, the Q value can be calculated by the following equation.
Q = f0 / BW
That is, the Q value is determined by the ratio between the oscillation frequency f (= resonance frequency f0) at which the intensity of the signal S1 is the maximum value Pmax and the frequency width BW (so-called half width) at which the intensity of the signal S1 is half of the maximum value Pmax. Can be calculated. The control unit 70 may calculate the Q value and output the calculation result to the display unit 80 so that the display unit 80 can display the Q value. Alternatively, the display unit 80 may calculate the Q value and display the Q value. In addition, the display unit 80 displays a comment that the heat treatment is difficult or impossible when the Q value is lower than a predetermined lower limit value, and a frequency sweep when the Q value is higher than the predetermined upper limit value. A comment useful for the operator, such as a comment indicating that it is necessary to reduce the step size, is displayed.

  Next, in the microwave device 100 of the present embodiment, the frequency response characteristic of the electromagnetic field strength and the frequency response characteristic of the electromagnetic field intensity of the reflected wave displayed on the display unit 80 are shown in FIGS. 7 and the operator's work according to the display content will be described. In the following, a case will be described in which ethanol is used as a liquid to be processed and ethanol at room temperature (for example, 30 ° C.) is heated to a predetermined temperature.

  For example, the operator causes the control unit 70 to execute the measurement mode before raising the temperature of ethanol. In this state, ethanol is circulating at room temperature (30 ° C.). When the measurement mode is executed by the control unit 70, each data of the first signal S10 and the second signal S20 is input to the display unit 80 from the control unit 70. The display unit 80 composed of a personal computer draws a frequency response characteristic curve of the electromagnetic field intensity of the cavity resonator 30 and a frequency response characteristic curve of the electromagnetic field intensity of the reflected wave on the display based on each input data. And display. This measurement mode is completed instantly. Thereafter, the microwave device 100 is in a standby state until the operator operates the changeover switch.

  FIG. 5 shows the display contents when the temperature of ethanol is 30 ° C. In the case of ethanol, at 30 ° C., there are almost no peaks or valleys in both the first signal S10 and the second signal S20. At this temperature, the operator can grasp that the Q value is extremely low, it is difficult to specify the resonance frequency f0, and the intensity of the reflected wave is high over the entire sweep range. Then, based on the information obtained from the display unit 80, for example, the operator sets the oscillation frequency f in the processing mode to a predetermined frequency in the ISM frequency band, or initializes the microwave output power in the processing mode. Various operating conditions can be appropriately adjusted, for example, by making the value larger than the value or setting the ethanol flow rate to be smaller than the initial set value. Thereafter, when the operation mode is switched from the measurement mode to the processing mode, the control unit 70 causes the processing mode based on the adjusted operating condition to be executed (that is, starts the heating process).

  FIG. 6 shows an example of the contents displayed on the display unit 80 when the temperature reaches 69.5 ° C. during the temperature rising from 30 ° C. in the processing mode and is switched to the measurement mode. As shown in FIG. 6, when the temperature changes, the shapes of the first signal S10 and the second signal S20 (that is, frequency response characteristics) change according to the temperature change. The display unit 80 is configured to be able to display the previous display contents in an overlapping manner. The operator can grasp that although the frequency response characteristic has changed, the amount of change is small. And an operator can return an operation mode to processing mode, for example, and can restart heat processing on the same conditions as the last operating conditions.

  FIG. 7 shows a state in which display contents obtained by appropriately switching to the measurement mode are displayed on the display unit 80 while being heated from 30 ° C. to 150.8 ° C. (that is, during execution of the processing mode). Is shown. When the temperature is higher than 69.5 ° C., the operator grasps that the peaks and valleys of the first signal S10 and the second signal S20 gradually appear, the Q value gradually increases, the resonance frequency f0 gradually increases, and the like. be able to. And the change state of the frequency response characteristic according to a temperature change can be grasped from the low temperature region to the entire high temperature region. As a result, the operator can grasp that the resonance frequency f0 is within the ISM frequency band at least from the middle temperature region to the high temperature region. More specifically, the operator can grasp that the resonance state is hardly obtained in the low temperature region, the Q value is extremely low, and the like. In addition, although the operator can obtain a resonance state in the intermediate temperature region, the operator can grasp that it is difficult to accurately specify the resonance frequency f0. The operator can obtain a good resonance state and a good matching in the high temperature region, can accurately specify the resonance frequency f0, and particularly has a high Q value in the vicinity of 150.8 ° C. Etc. can be grasped. Therefore, the operator can set the optimum operating condition for each temperature region by making maximum use of the information obtained for each temperature region.

  After specifying the operating conditions for each temperature region as described above, when the same type of liquid to be processed is heat-treated again, it is not necessary to execute the measurement mode, and the heat treatment is performed based on the obtained operating conditions. Just do it. In the above description, the case where the heat treatment is performed in an appropriate operating condition in the low temperature region is described as an example. For example, when the temperature rise time in the low temperature region becomes long, the illustration is performed. Although omitted, in the next heat treatment, it is preheated to a temperature in the middle temperature region by a preheating mechanism such as a heater separately provided with ethanol, and the heat treatment is started from the state in the middle temperature region (that is, the processing mode is executed). It may be. That is, you may comprise the heat processing system provided with the preheating mechanism which preheats to-be-processed liquid and supplies to the microwave apparatus 100, and the microwave apparatus 100. FIG. In the intermediate temperature region and the high temperature region, the resonance frequency f0 can be detected by the control unit 70 and the oscillation frequency f can be tuned to the resonance frequency f0 by the frequency control process in the processing mode. In the case of performing the heat treatment from the state, the processing mode may be executed without adjusting the operation conditions by the operator.

  When the Q value is high as in the high temperature region shown in FIG. 7, the reflection from the cavity resonator 30 increases when the oscillation frequency f slightly deviates from the actual resonance frequency f 0, and the cavity resonator 30 has an internal reflection. The electric field strength is reduced. Therefore, when it is known in advance that a temperature region having a high Q value exists, the operator may reduce the set value of the frequency sweep step size. As described above, if information on the frequency response characteristics for each temperature region can be obtained, then, when the same type of liquid to be processed is heat-treated, the operator can perform how to heat the liquid to be processed. Various measures can be considered. That is, the frequency response characteristic information for each temperature is extremely useful information.

According to the microwave apparatus according to the present embodiment, the control unit (output unit) 70 changes the first power monitor (first measurement unit) 50 and the second power monitor (second unit) that change according to the frequency sweep of the microwave. (Measurement unit) 60 sequentially stores the measurement results, outputs a first signal S10 indicating the frequency response characteristics of the electromagnetic field intensity in the cavity resonator 30 in the sweep range, and the electromagnetic field intensity of the reflected wave in the sweep range. The second signal S20 indicating the frequency response characteristic can be output. Since the frequency sweep of the microwave can be performed in a very short time, the operator can obtain the data of the first signal S10 and the data of the second signal S20 at a predetermined temperature, for example. In addition, when the temperature of the liquid to be processed (object to be processed) changes, the data of the first signal S10 and the data of the second signal S20 can be obtained for each changed temperature. Therefore, for example, even when a liquid to be processed such as ethanol having a large change in dielectric characteristics in response to a temperature change is a processing target, the operator uses the acquired data group for each temperature to perform tuning and matching. It is possible to accurately recognize the state of the apparatus for each temperature with respect to the requirements, and it is possible to appropriately adjust the operating conditions based on the obtained information.
In this way, according to the microwave device 100, it is possible to acquire and output useful information when determining the operating conditions.

  In the present embodiment, the operation mode of the apparatus can be instantaneously switched between the processing mode and the measurement mode. Thereby, the operation mode of the apparatus can be instantaneously switched from the processing mode to the measurement mode or from the measurement mode to the processing mode. Therefore, for example, in the process of raising the temperature of the liquid to be treated in the treatment mode, it is possible to appropriately switch to the measurement mode and grasp the change in the frequency response characteristics during the temperature rise. The frequency response characteristic can be grasped not only at the time of temperature rise but also before the temperature rise or during the cooling. Specifically, after the temperature of the liquid to be processed is once raised to a high temperature region by using a processing mode or a separately provided heater, the measurement mode is executed when the temperature of the liquid to be processed drops to a desired temperature. The change of the frequency response characteristic during the cooling can be grasped.

  In the present embodiment, the display unit 80 that displays the frequency response characteristics based on the first signal S10 and the second signal S20 is provided. Thus, the operator can easily visually recognize the frequency response characteristic of the apparatus.

In the present embodiment, the case where the oscillation frequency f is adjusted to tune the oscillation frequency f and the resonance frequency f0 has been described as an example. However, the present invention is not limited to this, and the dielectric characteristics in the cavity resonator 30 are also described. May be adjusted to adjust the resonance frequency f0 to achieve tuning.
For example, when a liquid having a low dielectric constant, such as xylene, toluene, or a general nonpolar solvent, is used as the liquid to be processed, the resonance frequency f0 may be higher than the upper limit value of the ISM frequency band. As a result, the oscillation frequency f cannot be tuned to the resonance frequency f0 within the ISM frequency band, and thus heating that makes use of the advantages of the cavity resonator 30 may not be possible. The operator's adjustment work assuming such a case will be described with reference to FIG.

  For example, it is assumed that the operator grasps that the resonance frequency f0 is higher than the upper limit value of the ISM frequency band by the shape of the first signal S10 obtained by the frequency sweep in the ISM frequency band. In this case, as shown in FIG. 8, for example, the operator arranges a dielectric piece 90 formed in a cylindrical shape and extending in one direction and having a predetermined dielectric constant so as to cover the flow tube 40 in the irradiation chamber 32. Good. Thus, by arranging the dielectric piece 90 having a predetermined dielectric constant in the vicinity of the liquid to be treated, the actual resonance frequency f0 can be lowered. As a result, the actual resonance frequency f0 may be within the ISM frequency band.

  FIG. 9 is a diagram for explaining a modification of the dielectric piece 90 for adjusting the actual resonance frequency f0 of the cavity resonator 30, and FIG. 9A is a longitudinal sectional view of the dielectric piece. FIG. 9B is a cross-sectional view taken along arrow X1-X1 shown in FIG. The dielectric piece 90 according to this modification is formed in a cylindrical shape so as to extend in one direction and have different dielectric characteristics in the extending direction. Specifically, the dielectric piece 90 has a plurality of through holes 90a opened at intervals in the extending direction and the circumferential direction. Further, the size of the through hole 90a is opened so as to increase toward one end side in the extending direction. Thus, by forming the dielectric piece 90 so that the dielectric characteristics in the extending direction are different, the dielectric characteristics in the cavity resonator 30 can be finely adjusted as appropriate.

  FIG. 10 is a diagram for explaining a case where the dielectric piece 90 is arranged so that the position in the cavity resonator 30 can be adjusted. For example, the dielectric piece 90 is supported so as to be movable in the extending direction of the central axis C of the irradiation chamber 32 as shown in FIG. For example, the operator moves the dielectric piece 90 and adjusts the amount of the dielectric piece 90 in the irradiation chamber 32 so that the resonance frequency f0 can be adjusted. For example, in the state shown in FIG. 10, when the operator wants to lower the resonance frequency f0, the operator may move the dielectric piece 90 upward. On the other hand, when it is desired to increase the resonance frequency f0 in the state shown in FIG. 10, the operator may move the dielectric piece 90 downward. Here, the dielectric loss factor of the liquid to be treated and the dielectric piece 90 generally decreases as the temperature increases. However, for example, some dielectric materials such as a polymer (for example, PTFE) have a characteristic that in the vicinity of the softening point, the dielectric constant increases as the temperature rises and approaches the softening point. Therefore, for example, when the heating target temperature is a temperature in the vicinity of the softening point of a polymer or the like, in order to reduce the amount of change in the resonance frequency f0 due to the decrease in the dielectric loss factor of the liquid to be processed due to the temperature increase, A dielectric material such as a polymer having the above characteristics may be used as the material of the piece 90. Note that the dielectric piece 90 shown in FIG. 9 may be arranged so that its position can be adjusted as shown in FIG.

  Further, in this embodiment, as shown in FIGS. 1 and 2, both end portions of the flow tube 40 made of a quartz glass snake tube are assumed to extend linearly along the central axis C of the irradiation chamber 32. Although explained, it is not limited to this. For example, you may comprise so that it may extend | stretch in the position shifted from the central axis C, as shown in FIG. In this case, the rod-shaped dielectric piece 90 may be disposed so as to be movable along the central axis C along the spiral center of the flow pipe 40 made of a serpentine tube, that is, along the central axis C. As described above, the operator can adjust the insertion amount in a state where the dielectric piece 90 is inserted in the region where the electromagnetic field strength is the strongest, so that the resonance frequency f0 can be adjusted effectively. . In this case, as shown in FIG. 12, a short cylindrical dielectric piece 90 ′ is further arranged so as to cover one end of the flow pipe 40, and the position of the dielectric piece 90 ′ is adjustable. Also good. That is, the number of dielectric pieces is not limited to one, and a plurality of pieces may be arranged so that their positions can be adjusted. Thereby, the operator can adjust the resonance frequency f0 more finely.

  13 and 14 are conceptual diagrams for explaining another modified example of the flow pipe 40. FIG. The flow pipe 40 is not limited to a snake pipe but may be an L-shaped pipe formed in an L-shape as shown in FIGS. 13 and 14. For example, one end of the L-shaped flow pipe 40 passes through the upper wall 33 of the cavity resonator 30, and the other end is the side wall of the cavity resonator 30 (any one of the side walls 36 to 38). The slit 30 'is formed so as to extend in the direction of the central axis C. The L-shaped flow pipe 40 is configured to be movable in the direction of the central axis C. Thus, by configuring the position of the flow pipe 40 so as to be adjustable, the operator can adjust the resonance frequency f0 and the like by changing the dielectric characteristics in the cavity resonator 30. In addition, although illustration is abbreviate | omitted, the distribution | circulation pipe | tube 40 can use piping which has not only a serpentine tube and an L-shaped tube but a suitable shape.

Moreover, although each said modification demonstrated the case where it was comprised so that the dielectric property in the cavity resonator 30 could be adjusted by arrange | positioning the dielectric piece 90 or adjusting the position of the flow pipe 40. However, the present invention is not limited to this, and the dielectric properties of the liquid to be processed may be adjustable within an allowable range.
For example, when the liquid to be processed is composed of a solvent and a substrate, although not shown in the figure, it is preferable that the flow rate of the solvent of the liquid to be processed and the flow rate of the substrate of the liquid to be processed can be adjusted. Accordingly, the operator can finely adjust the flow rates of the solvent and the substrate based on the information obtained by the display unit 80, and can appropriately adjust the dielectric characteristics of the liquid to be processed. Further, although not shown in the drawings, an auxiliary flow pipe connected to the flow pipe 40 may be further provided, which further includes an auxiliary flow pipe for circulating the ionic liquid and adding it to the liquid to be treated. The auxiliary flow pipe is connected to the upstream side of the flow pipe 40. Thus, the operator can adjust the dielectric characteristics of the liquid to be processed by adding an appropriate amount of ionic fluid to the liquid to be processed based on the information obtained by the display unit 80.

  In the present embodiment, the frequency response characteristic of the electromagnetic field strength of the cavity resonator 30 and the frequency response characteristic of the electromagnetic field intensity of the reflected wave are respectively set such that the horizontal axis is the oscillation frequency f and the vertical axis is the electromagnetic field strength. Although the description has been given of the case where the drawing is performed on the grab having the strength, the present invention is not limited thereto, and the display unit 80 may be configured to draw as a Smith chart, for example. Further, the display format of the frequency response characteristics may be appropriately switched.

  In the present embodiment, the microwave device 100 includes the display unit 80. However, the present invention is not limited thereto, and the display unit 80 may not be included. In this case, the microwave device 100 only needs to be able to output the first signal S10 and the second signal S20 to an external display unit, a storage device, or the like. The operator may ascertain the frequency response characteristics as appropriate based on the first signal S10 and the second signal S20 output to the outside.

In the present embodiment, the operator adjusts the dielectric characteristics in the cavity resonator 30 (position adjustment and distribution of the dielectric pieces 90 and 90 ′) based on various information related to the frequency response characteristics displayed on the display unit 80. The case of adjusting the position of the tube 40) and adjusting the dielectric characteristics of the liquid to be treated (adjusting the flow rate of the solvent and the substrate and adding the ionic fluid) have been described as examples, but the present invention is not limited thereto. The microwave device 100 is configured such that, for example, the control unit 70 can adjust the dielectric characteristics in the cavity resonator 30 and the dielectric characteristics of the liquid to be processed based on the first signal S10 and the second signal S20. May be. In the present embodiment, the detection of the resonance frequency f0 and the calculation of the Q value are performed based on the measurement result of the first power monitor 50, and by tuning the oscillation frequency f and the resonance frequency f0, The case of minimization has been described as an example, but the present invention is not limited to this. For example, the configuration may be such that the detection of the resonance frequency f0 and the calculation of the Q value are performed based on the measurement result of the second power monitor 60, and the tuning and the reflected wave are minimized. Therefore, the microwave device 100 only needs to include at least one of the first power monitor 50 and the second power monitor 60. When the microwave device 100 includes only the first power monitor 50, the control unit (output unit) 70 outputs only the first signal, and the display unit 80 based on the first signal causes the cavity resonator 30 in the sweep range. It is only necessary to display the frequency response characteristics of the electromagnetic field strength. When the microwave device 100 includes only the second power monitor 60, the control unit 70 outputs only the second signal, and the display unit 80 performs frequency response of the electromagnetic field intensity of the reflected wave in the sweep range based on the second signal. What is necessary is just to display a characteristic.
As described above, the microwave device 100 includes the cavity resonator 30 and the microwave generator 10, and can heat-treat the object to be processed in the cavity resonator 30. Measurement unit) 50 and at least one of second power monitor (second measurement unit) 60 and measurement of at least one of first power monitor 50 and second power monitor 60 that change according to the frequency sweep of the microwave, respectively. It is only necessary to include a control unit (output unit) 70 that sequentially stores the results and outputs at least one of the first signal S10 and the second signal S20 in the sweep range.

  In the present embodiment, the microwave apparatus 100 is described as an example of a flow type in which heat treatment is performed while circulating the liquid to be treated. However, the present invention is not limited to this, and a batch type in which heat treatment is performed in a stationary state is also possible. Good. Moreover, in this embodiment, although the to-be-processed object shall be a liquid (namely, to-be-processed liquid), not only this but solid may be sufficient. Further, in the present embodiment, the cavity resonator 30 has been described as including the irradiation chamber 32 of a square columnar cavity. However, the present invention is not limited thereto, and may be configured to include an irradiation chamber of a cylindrical cavity. . In this case, if nothing is contained in the cavity resonator 30, the electromagnetic field in the TM010 mode is excited.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not restrict | limited to the said embodiment and the said modification, A various deformation | transformation and change are possible based on the technical idea of this invention.

DESCRIPTION OF SYMBOLS 10 ... Microwave generator 30 ... Cavity resonator 40 ... Flow pipe 41 ... Auxiliary flow pipe 50 ... 1st power monitor (1st measurement part)
60 ... 2nd power monitor (2nd measurement part)
70: Control unit (output unit)
DESCRIPTION OF SYMBOLS 80 ... Display part 90 ... Dielectric piece 100 ... Microwave apparatus

Claims (9)

A cavity resonator for resonating a microwave and a microwave generator capable of generating the microwave and sweeping the frequency within a predetermined sweep range are provided, and the object to be processed is heated in the cavity resonator. A microwave device capable of processing,
A first measuring unit for measuring the electromagnetic field strength in the cavity, and a second measuring unit for measuring the electromagnetic field strength of the reflected wave reflected from the cavity resonator toward the microwave generator. Including at least one of
The measurement result of at least one of the first measurement unit and the second measurement unit, which respectively change according to the frequency sweep of the microwave, is sequentially stored, and the frequency of the electromagnetic field intensity in the cavity resonator in the sweep range A microwave device including an output unit that outputs at least one of a first signal indicating response characteristics and a second signal indicating frequency response characteristics of electromagnetic field intensity of the reflected wave in the sweep range.   A processing mode in which the object to be heated is heated, and a measurement mode in which the microwave frequency is swept within the predetermined sweep range, and at least one of the first signal and the second signal is acquired and output. The microwave device according to claim 1, wherein the operation mode can be switched between the two.   The microwave device according to claim 1, further comprising a display unit that displays the frequency response characteristic based on at least one of the first signal and the second signal.   4. A dielectric piece for adjusting an actual resonance frequency of the cavity resonator, further comprising a dielectric piece arranged so that its position in the cavity resonator can be adjusted. The microwave device according to any one of the above.   The microwave device according to claim 1, wherein the dielectric piece is formed so as to extend in one direction and have different dielectric characteristics in the extending direction.   The microwave device according to any one of claims 1 to 5, further comprising a flow pipe that is disposed so as to penetrate through the cavity resonator and flows a liquid to be processed as the object to be processed. The liquid to be treated consists of a solvent and a substrate,
The microwave device according to claim 6, wherein the flow rate of the solvent of the liquid to be treated and the flow rate of the substrate of the liquid to be treated can be adjusted.   The microwave device according to claim 6 or 7, wherein the microwave device includes an auxiliary flow tube connected to the flow tube for flowing an ionic liquid and adding the ionic liquid to the liquid to be treated. The microwave device according to any one of claims 6 to 8,
A preheating mechanism for preheating the liquid to be treated and supplying the liquid to the microwave device;
Heat treatment system equipped with.