Setting device for industrial magnetron and setting method for industrial magnetron

Abstract

To provide a setting device of an industrial magnetron capable of generating a stable plasma state even when changing from a low output to a rated output of a high output while reducing the cost of the whole device by using a single magnetron, and a setting method of the industrial magnetron.SOLUTION: A setting device 1 for an industrial magnetron includes a control unit 30 that sets an initial value of a voltage value using a sample product of an industrial magnetron 10 and sets a current value so that an output value of the industrial magnetron 10 becomes a rated output, and a storage unit 40 that stores the voltage value and the current value set by the control unit 30.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a setting device for an industrial magnetron, which is an electron tube that generates microwaves, and a setting method for an industrial magnetron. [Background technology]

[0002] In general, industrial magnetrons are capable of efficiently generating high frequency output, and are therefore widely used in fields such as radar equipment, medical equipment, cooking appliances such as microwave ovens, semiconductor manufacturing equipment, and other microwave application equipment. High-power microwaves are required for semiconductor equipment and industrial heating.

[0003] A magnetron is composed of a high-voltage DC power supply that generates a high voltage to be applied between the cathode and anode, a power supply that heats a filament to a specified temperature to emit electrons, a control circuit for these components, a waveguide for extracting microwave energy, and a housing to house these components.

[0004] A magnetron is composed of a cathode placed in the center of an anode cylinder and a magnet. A heater is wound around the cathode, and when a predetermined current is applied to it, thermions are emitted from the cathode. The thermions are attracted to the anode cylinder, but the magnetic field created by the magnet causes them to rotate and orbit around the cathode. This vibration resonates in a cavity on the anode side, and the energy is extracted as radio waves (microwaves) from the output section (antenna).

[0005] In industrial magnetrons, when the plasma generated when microwaves are generated is used for semiconductor sputtering or the like, a stable plasma state is required.

[0006] Patent document 1 describes a magnetron drive power supply device that has coils corresponding to magnetrons connected in parallel with each other, and adjusts the current value so that the composite magnetic field generated by the current supplied to the coils becomes zero. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 8-167384 Summary of the Invention [Problem to be solved by the invention]

[0008] The magnetron-driven power supply device described in Patent Document 1 has the problem that it requires multiple magnetrons, which increases the cost of the entire device. In other words, the use of multiple magnetrons results in higher costs than using a single magnetron. There is no device that can stabilize the plasma state using only a single magnetron.

[0009] The present invention has been made in view of the above circumstances, and aims to provide an industrial magnetron setting device and an industrial magnetron setting method that can reduce the cost of the entire device by using a single magnetron, while generating a stable plasma state even when the rated output is changed from low output to high output. [Means for solving the problem]

[0010] In order to solve the above problem, there is provided an industrial magnetron setting device that sets the voltage and current values ​​to be applied to the anode of an industrial magnetron, the device comprising: a control unit that uses a sample of the industrial magnetron to set an initial value of the voltage value and sets the current value so that the output value of the industrial magnetron becomes the rated output; and a memory unit that stores the voltage and current values ​​set by the control unit, wherein the control unit reduces the voltage value so that the output value becomes half or more of the rated output, and then sets the current value so that the output value becomes the rated output. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an industrial magnetron setting device and an industrial magnetron setting method that can reduce the cost of the entire device by using a single magnetron, while generating a stable plasma state even when the rated output is changed from low output to high output. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing the configuration of an industrial magnetron setting device according to an embodiment of the present invention; [Figure 2A] FIG. 2 is a diagram showing an example of a spectral region map stored in a memory unit of the setting device for an industrial magnetron according to an embodiment of the present invention. [Figure 2B] FIG. 2 is a diagram showing an example of a spectral region map stored in a memory unit of the setting device for an industrial magnetron according to an embodiment of the present invention. [Figure 2C] FIG. 2 is a diagram showing an example of a spectral region map stored in a memory unit of the setting device for an industrial magnetron according to an embodiment of the present invention. [Figure 3] 1 is a cross-sectional view showing the configuration of an industrial magnetron according to an embodiment of the present invention. [Figure 4] 1 is a plan view of a main part of an industrial magnetron according to an embodiment of the present invention, including a cathode portion and an anode portion. [Figure 5A] 1 is a diagram illustrating the cause of deterioration of the spectrum characteristics of an industrial magnetron according to an embodiment of the present invention. FIG. [Figure 5B] 1 is a diagram illustrating the cause of deterioration of the spectrum characteristics of an industrial magnetron according to an embodiment of the present invention. FIG. [Figure 6A] FIG. 2 is a diagram illustrating an image of a spectrum improvement region of the industrial magnetron setting device according to the embodiment of the present invention. [Figure 6B] FIG. 2 is a diagram illustrating an image of a spectrum improvement region of the industrial magnetron setting device according to the embodiment of the present invention. [Figure 6C] FIG. 2 is a diagram illustrating an image of a spectrum improvement region of the industrial magnetron setting device according to the embodiment of the present invention. [Figure 7] 3 is a flowchart showing a process for creating a spectral region map of the industrial magnetron setting device according to the embodiment of the present invention. [Figure 8A] 4 is a flowchart showing a process for setting voltage and current values ​​of a sample industrial magnetron of the industrial magnetron setting device according to the embodiment of the present invention. [Figure 8B] 4 is a flowchart showing a process for setting voltage and current values ​​of a sample industrial magnetron of the industrial magnetron setting device according to the embodiment of the present invention. [Figure 9] FIG. 10 is a table showing the results of prototyping a sample industrial magnetron of the industrial magnetron setting device according to the embodiment of the present invention. [Figure 10] FIG. 10 is a diagram showing a filament voltage Ef of the comparative example 2 of the prototype example of FIG. 9 and the present embodiment. [Figure 11] FIG. 10 is a diagram showing an example of spectrum characteristic results when Ib is 600 mA and filament voltages Ef are Ef 3.7 V, Ef 3.2 V, and Ef 2.7 V in the specifications of Comparative Example 1 (Eb 8.9 kV), Comparative Example 2 (Eb 8.5 kV), and the present embodiment (Eb 7.5 kV) in FIG. [Figure 12] FIG. 10 is a diagram showing a comparison of the spectrum characteristics of the specifications (Eb8.9 kV) of Comparative Example 1 of FIG. 9 and the specifications (Eb7.5 kV) of this embodiment over a wide range of 1 to 10 kW. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a diagram showing the configuration of an industrial magnetron setting device according to an embodiment of the present invention. This embodiment is an industrial magnetron setting device that sets the voltage and current values ​​to be applied to the anode of the industrial magnetron.

[0014] [Overall configuration] As shown in FIG. 1, the industrial magnetron setting device 1 includes an industrial magnetron 10 (FIGS. 3 and 4), a high-voltage power supply unit 20, an anode voltmeter 21 (measurement unit), an anode ammeter 22 (measurement unit), a filament voltmeter 23 (measurement unit), a filament ammeter 24 (measurement unit), a control unit 30, and a memory unit 40.

[0015] <Control unit 30> - How to set the voltage and current values ​​using a sample product (how to lower the anode voltage Eb [kV] and increase the anode current Ib [mA]) The control unit 30 uses a sample industrial magnetron 10 to set an initial value for the voltage value, and sets a current value so that the output value of the industrial magnetron 10 becomes the rated output. The control unit 30 reduces the voltage value so that the output value becomes half or more of the rated output (for example, 80% of the rated output), and then sets the current value so that the output value becomes the rated output. Here, the rated output obtained by setting the voltage and current values ​​of the sample product is set in the range of 2 kW to 10 kW.

[0016] - Applying sample product settings The control unit 30 reads out from the storage unit 40 the voltage and current values ​​set using the sample product, and sets them to the voltage and current values ​​to be applied to the anode of the industrial magnetron 10 other than the sample product.

[0017] Spectral region map creation The control unit 30 uses the output value and voltage value of the industrial magnetron 10 as parameters for each rated output anode voltage to create a spectrum region map 50 (FIGS. 2A-C) that is divided into a good spectrum region 51 (white area in FIG. 2A, etc.) where no disturbance occurs in the microwave spectrum waveform, a bad spectrum region 52 (dotted area in FIG. 2A, etc.) where disturbance occurs in the microwave spectrum waveform, and a magnetron failure region 53 (shaded area in FIG. 2A, etc.) where magnetron failure is expected. Note that FIGS. 2A-C correspond to FIGS. 6A-C, which will be described later.

[0018] Setting the anode voltage at rated output The control unit 30 uses a sample of the industrial magnetron 10, and by referring to the first spectrum region map 50 (FIG. 6B) created based on the anode voltage of the first rated output (FIG. 6B: Eb 8.5 kV), sets an initial value of the voltage value within the good spectrum region 51 of the first spectrum region map 50 (FIG. 6B), sets a current value so that the output value of the industrial magnetron 10 becomes the rated output (FIG. 6B: Eb 8.5 kV), and sets a current value so that the rated output becomes equal to the good spectrum region 51 of the first spectrum region map 50 (FIG. 6B). If the output value is not within the good spectrum region 51 of the first rated output (Eb8.5 kV in FIG. 6B), a second spectrum region map 50 (FIG. 6C) is created based on the anode voltage of the second rated output (Eb7.5 kV in FIG. 6C) created by lowering the anode voltage of the first rated output (Eb8.5 kV in FIG. 6B), and the voltage value is set within the good spectrum region 51 of the second spectrum region map 50 (FIG. 6C), and the current value is set so that the output value of the industrial magnetron 10 becomes the rated output (Eb7.5 kV in FIG. 6C).

[0019] When using the anode voltage of the second rated output (Eb7.5 kV in FIG. 6C), the control unit 30 maintains the rated output by increasing the anode current Ib by the amount by which the anode voltage Eb of the first rated output (Eb8.5 kV in FIG. 6B) is reduced.

[0020] Filament voltage Ef setting The control unit 30 lowers the filament voltage Ef within the good spectrum region 51 by referring to the spectrum region map 50 (Figures 6A-6C) in the memory unit 40 based on the measurement results of the measurement unit that measures the voltage and current values ​​of the filament and the anode of the industrial magnetron.

[0021] Setting the rated output to reduce the filament voltage Ef When the control unit 30 cannot lower the filament voltage Ef within the good spectrum region 51 of the first spectrum region map 50 (FIG. 6B) created based on the anode voltage Eb of the first rated output (FIG. 6B: Eb 8.5 kV), the control unit 30 refers to the second spectrum region map 50 (FIG. 6C) created based on the anode voltage Eb of the second rated output (FIG. 6C: Eb 7.5 kV) created by lowering the anode voltage Eb of the first rated output (FIG. 6B: Eb 8.5 kV), and lowers the filament voltage Ef within the good spectrum region 51 of the second spectrum region map 50 (FIG. 6C).

[0022] <Storage section 40> The storage unit 40 stores the voltage and current values ​​set by the control unit 30 . The storage unit 40 stores the spectral region map 50 (FIGS. 2A-C) created by the control unit 30.

[0023] [Spectral Region Map] 2A-C are diagrams showing examples of a spectrum region map 50 stored in the memory unit 40 of the industrial magnetron setting device 1. FIG. 2A shows the spectrum region map 50 when the anode voltage Eb is 8.9 kV, FIG. 2B shows the spectrum region map 50 when the anode voltage Eb is 8.5 kV, and FIG. 2C shows the spectrum region map 50 when the anode voltage Eb is 7.5 kV. The horizontal axes of FIGS. 2A-C represent anode current [mA] and output value [kW], and the vertical axes represent filament voltage [V]. The output value [kW] is an estimated output when an anode current [mA] is applied at each rated anode voltage Eb.

[0024] The spectrum region map 50 shown in Figures 2A-2C has regions divided into a good spectrum region 51, a bad spectrum region 52, and a magnetron failure region 53, with the output value and voltage value of an industrial magnetron as parameters, for each rated anode voltage Eb.

[0025] The good spectrum region 51 indicates a region in which the industrial magnetron 10 operates well. As shown in FIGS. 2A-C, the good spectrum region 51 has two regions: one where the output value is in the range of approximately 1000 mA to 1800 mA, and the other where the output value is in the range of 400 mA to 800 mA, as shown in FIGS. 2B and C. As can be seen from comparing FIG. 2A with FIGS. 2B and C, it was found that the good spectrum region 51 expands when the anode voltage Eb is lowered.

[0026] The spectrum degradation region 52 indicates the region obtained by removing the good spectrum region 51 and the magnetron failure region 53 from the entire spectrum region. The magnetron failure region 53 has a pattern that tends to be almost the same, so it was found that as the good spectrum region 51 expands, the spectrum degradation region 52 decreases.

[0027] The spectrum region map 50 shown in FIGS. 2A to 2C is a characteristic diagram discovered by the inventors in advance through prototypes and the like.

[0028] FIG. 3 is a cross-sectional view showing the configuration of an industrial magnetron 10 according to an embodiment of the present invention. 3, the industrial magnetron 10 includes a spirally formed cathode filament 151 (cathode) serving as a heat emission source, a plurality of anode vanes (also simply referred to as vanes) 152 (anode) arranged around the cathode filament 151, an anode cylinder 153 supporting the anode vanes 152, a pair of annular permanent magnets 154a and 154b arranged at the upper and lower ends of the anode cylinder 153, magnetic poles 155a and 155b, and a yoke 156. The anode vanes 152 and the anode cylinder 153 are integrated together by brazing or the like or by extrusion molding, and form part of the anode section.

[0029] The multiple anode vanes 152 are arranged radially around the cathode filament 151. An interaction space 163 is formed between the cathode filament 151 and the anode vanes 152. The area surrounded by two adjacent anode vanes 152 and the anode cylinder 153 forms a resonant cavity.

[0030] A pair of magnetic poles 155a and 155b made of a ferromagnetic material such as soft iron are disposed between the anode cylinder 153 and the permanent magnets 154a and 154b.

[0031] An antenna lead 157 is electrically connected to the anode vane 152. The antenna lead 157 is covered with a dome-shaped antenna cover 158.

[0032] The industrial magnetron 10 includes a magnetic circuit section 170, an upper end shield 171, a lower end shield 172, a center lead 173 of the cathode lead, a side lead 174 of the cathode lead, an input ceramic 175, a terminal board 176, a cathode section 178, an anode section 179, and an exhaust pipe 180.

[0033] The magnetic circuit section 170 includes permanent magnets 154a and 154b and magnetic poles 155a and 155b, which are magnetic generation sources, and a yoke 156. The cathode section 178 includes a cathode filament 151, which is a thermionic emission source, an upper end shield 171, a lower end shield 172, a center lead 173 of the cathode lead, and side leads 174 of the cathode lead. The anode section 179 includes a plurality of anode vanes 152, straps 164 fitted to the tip ends of every other anode vane 152, and an anode cylinder 153. The anode section 179 is fixed to the plurality of anode vanes 152 and the anode cylinder 153 by brazing or the like, or is integrally formed with the anode cylinder 153 by extrusion molding.

[0034] In the industrial magnetron 10 having these components, the yoke 156 constitutes the magnetic circuit section 170. The yoke 156 also serves as a housing that houses the permanent magnets 154a, 154b, the magnetic poles 155a, 155b, the antenna lead 157, the cathode section 178, and the anode section 179, and is disposed on the microwave output side, and is also used as a coupling member with an external mechanism (not shown).

[0035] The magnetic flux generated from the permanent magnets 154a, 154b passes through the magnetic poles 155a, 155b and enters the interaction space 163 formed between the cathode filament 151 and the anode vane 152, providing the necessary DC magnetic field in the axial direction, i.e., the vertical direction of the industrial magnetron 10.

[0036] This DC magnetic field exerts the following effect: In a state where the main body axis of the industrial magnetron 10 is installed perpendicular to a horizontal plane, when a magnetic flux is applied in the perpendicular direction (axial direction) to electrons flying horizontally from the cathode filament 151 toward the anode vane 152, a Lorentz force is applied to the electrons. This Lorentz force causes the electrons to fly while spiraling horizontally, and a high-frequency electric field is formed in the anode vane 152.

[0037] A heater is wound around the cathode filament 151 (cathode), and when a predetermined current is applied to it, thermoelectrons are emitted from the cathode filament 151. The thermoelectrons are attracted to the anode cylinder 153, but are caused to rotate and circulate around the cathode filament 151 by the magnetic field formed by permanent magnets 154a and 154b, and this vibration is resonated in a cavity provided on the anode vane 152 (anode) side, and the energy is extracted as radio waves (microwaves) from the output section (antenna). The cathode filament 151 emits electrons when a negative high voltage of 4 kV to 8 kV DC is applied, and these electrons undergo spiral motion under the influence of the electric and magnetic fields as described above, forming a high-frequency electric field in each anode vane 152. This formed high-frequency electric field is output from an antenna block (not shown) to an external device through the antenna lead 157.

[0038] A filter structure 185 is attached to the bottom of the industrial magnetron 10, and is made up of a filter case 183 that supports a choke coil 181 and a feedthrough capacitor 182, and a lid 184 that closes the filter case 183. The choke coil 181 and the feedthrough capacitor 182 form an LC filter that suppresses low-frequency components transmitted from the cathode leads 173, 174. High-frequency components are shielded by the filter case 183 and its lid 184.

[0039] The exhaust pipe 180 is used to remove gas from inside the magnetron vacuum tube body, which encloses the cathode part 178, the anode part 179, and part of the inside of the antenna cover 158. After the gas is removed and a vacuum state is created, the tip of the exhaust pipe 180 is sealed.

[0040] The industrial magnetron 10 includes a cooling block 200 (cooling mechanism) arranged in a columnar shape around the outer periphery of the anode cylinder 153. The cooling block 200 has a cooling water passage 201 (refrigerant flow path) arranged around the inside thereof, through which cold water passes, and the cold water passing through the passage diffuses heat generated by the operation of the industrial magnetron 10.

[0041] FIG. 4 is a plan view of the main part including the cathode portion 178 and the anode portion 179 shown in FIG. 4, the ends of twelve anode vanes 152, each rectangular in plan view, are evenly arranged and fixed on the inner periphery of the anode cylinder 153. Furthermore, the tips of the anode vanes 152 are arranged in a circular pattern, protruding radially from the fixed positions toward the center of the cathode filament 151, and an interaction space 163 is formed between each tip of this circular arrangement and the cathode filament 151.

[0042] 4 is called a multi-segment anode structure, and is a cavity resonator divided by 12 anode vanes 152. The capacitance C and inductance L of each cavity resonator determine the resonant frequency, i.e., the oscillation frequency of the industrial magnetron 10. The inductance L is determined by the size of the cavity between each anode vane 152 located between the inner periphery of the anode cylinder 153 and the outer periphery of the annular strap 164. The larger the cavity, the larger the inductance L. In other words, the larger the inner diameter of the anode cylinder 153, the larger the cavity and therefore the larger the inductance L.

[0043] The capacitance C is determined by the gap between the tips of the anode vanes 152 that protrude toward the inner periphery of the strap 164. The smaller the gap, the larger the capacitance C. Also, the larger the area of ​​the opposing tips, the larger the capacitance C.

[0044] The upper end of the cathode filament 151, which is arranged at the circumferential center of the anode cylindrical body 153, is fixed to an output-side end shield 171, and the lower end is fixed to an input-side end shield 172. The output-side end shield 171 is supported by a center lead 173 of a rod-shaped cathode lead, and the input-side end shield 172 is supported by a side lead 174 of the rod-shaped cathode lead.

[0045] The operation of the industrial magnetron setting device 1 configured as above will be described below. (Explanation of the principle) First, the basic concept of the present invention will be described. 5A and 5B are diagrams for explaining the causes of deterioration in the spectrum characteristics of an industrial magnetron. For convenience of explanation, the number of anode vanes 152 is assumed to be eight, and the strap storage grooves 152a, notches 152b, and straps 164 (FIG. 4) are not shown. The inventors investigated improving the spectrum characteristics in order to stabilize the plasma state using only a single magnetron (the good / bad spectrum characteristics will be described later in Figures 11 and 12). They presumed that the cause of the poor spectrum was the breakage of spokes 150 (Figure 5A) (the anode current was cut off). They also presumed that a high frequency of collisions between electrons disrupts the spokes, causing them to break.

[0046] The inventors considered reducing the electron density in the spokes as a countermeasure. They found that the electron density in the spokes is correlated with the peak anode voltage (hereinafter referred to as anode voltage) Eb and the filament voltage Ef, and that the electron density in the spokes can be reduced by reducing the anode voltage Eb or the filament voltage Ef. However, the effects (factors) of reducing the electron density in the spokes differ between the anode voltage Eb and the filament voltage Ef.

[0047] (1) When lowering the anode voltage Eb When the anode voltage Eb is lowered, the spokes spread and the electron density decreases, which suppresses collisions between electrons and makes the spokes less likely to break (Figure 5B, symbol a: connected spokes).

[0048] (2) When lowering the filament voltage Ef Lowering the filament voltage Ef suppresses excess electron emission from the filament relative to the amount of electrons required to reach the anode. Electrons reach the anode while undergoing rotational motion, but suppressing excess electrons suppresses collisions between electrons within the spokes, which is thought to result in suppressing spoke disorder and making the spokes less likely to break (Figure 5B, symbol a: connected spokes).

[0049] As such, the anode voltage Eb and the filament voltage Ef have different effects on reducing the electron density of the spokes. In other words, there are two methods for reducing the electron density of the spokes: one is to reduce the anode voltage Eb, and the other is to reduce the filament voltage Ef, and both can be used together. Furthermore, if the anode voltage Eb is lowered, it is expected that the output will not meet the rated output. Therefore, according to equation (1), the anode current Ib is increased by the amount of the lowered anode voltage Eb, and the output Po is maintained at the rated output.

[0050]

number

[0051] The oscillation efficiency η is expressed as output = input × η, with approximately 20 to 30% of the input (current × voltage) being lost as heat (1-η).

[0052] Furthermore, when the filament voltage Ef is reduced, it is required that the filament voltage Ef is within a good spectrum region 51 of the spectrum region map 50 shown in FIGS. 2A to 2C (details will be described later). As described above, the present inventors are the first to disclose that the anode voltage Eb and / or filament voltage Ef can be lowered to stabilize the plasma state, and that the setting conditions for lowering the filament voltage Ef can be shown on the spectral region map 50.

[0053] (3) Spectrum improvement area image 6A-6C are diagrams for explaining an image of a spectrum improvement region. The same parts as those in FIGS. 2A-2C are assigned the same reference numerals. As described above, as shown in Figures 6A-C, by reducing the anode voltage Eb from 8.9 kV to 8.5 kV and from 8.5 kV to 7.5 kV, the good spectrum region 51 expands so as to reduce the magnetron failure region 53 (see symbol b in Figures 6B-C), and the good spectrum region 51 expands so as to reduce the degraded spectrum region 52 (see symbol c in Figures 6B-C). In particular, when the anode voltage Eb is reduced from 8.5 kV to 7.5 kV as shown by symbol c in Figures 6B-C, the good spectrum region 51 can be significantly expanded. In this way, by lowering the anode voltage Eb, the good spectrum region 51 can be increased and the spectrum can be improved.

[0054] Lowering the filament voltage Ef also has the effect of making the spokes less likely to break. This effect will now be explained. The dashed and solid lines in Figures 6A-6C show the filament voltage Ef [V] versus the output value [kW]. For example, the anode voltage Eb of 8.9 kV shown in Figure 6A is used at the operating filament voltage Ef shown by the solid line in Figure 6A. Furthermore, the anode voltage Eb of 8.5 kV shown in Figure 6B is used at the operating filament voltage Ef shown by the solid line in Figure 6B.

[0055] Incidentally, even if the filament voltage Ef is lowered to the bottom dashed line, the output value range does not decrease. This is because after the filament voltage Ef reaches 0V, the line continues to the right end of the good spectrum range in a polygonal fashion. The increase in the output value range is affected by the anode voltage Eb, and is not affected by the filament voltage Ef.

[0056] By lowering the anode voltage Eb, the good spectrum region increases, and by lowering the operating filament voltage Ef, it becomes easier to enter the good spectrum region. In this way, by lowering the anode voltage Eb to 7.5 kV and also lowering the filament voltage Ef, a synergistic effect can be achieved that makes the spokes less likely to break.

[0057] The basic concept of the present invention has been explained above. Next, the operation of the industrial magnetron setting device 1 shown in FIG. [flowchart] FIG. 7 is a flowchart showing the process of creating the spectrum region map 50 of the setting device 1 for an industrial magnetron. In step S1, the control unit 30 (FIG. 1) uses a sample industrial magnetron 10 to create a spectrum region map 50 (FIGS. 2A-C) divided into a good spectrum region 51, a bad spectrum region 52, and a magnetron failure region 53, with the output value and voltage value of the industrial magnetron 10 as parameters for each rated output anode voltage Eb.

[0058] In step S2, the control unit 30 stores the created spectrum region map 50 in the storage unit 40 (FIG. 1), and ends the processing of this flow.

[0059] 8A and 8B are flowcharts showing the voltage and current value setting process for the sample industrial magnetron 10. FIG. In step S11, the control unit 30 (FIG. 1) sets an initial value of the voltage value to be applied to the anode of the industrial magnetron 10 (FIG. 1) (setting of the initial value of the voltage value).

[0060] In step S12, the control unit 30 sets the current value to be applied to the anode based on the voltage value set as the initial value so that the output value of the sample industrial magnetron 10 becomes the rated output (setting of the current value).

[0061] In step S13, the control unit 30 measures the voltage and current values ​​of the anode and the voltage and current values ​​of the filament based on the detected values ​​of each measuring instrument (anode voltmeter 21, anode ammeter 22, filament voltmeter 23, filament ammeter 24) (Figure 1) (measurement of voltage and current values).

[0062] In step S14, the control unit 30 reads out the spectrum region map 50 (FIG. 2) from the storage unit 40 (FIG. 1) based on the anode voltage Eb of the rated output.

[0063] In step S15, the control unit 30 uses the output value and voltage value of the sample industrial magnetron 10 as parameters, refers to the spectrum region map 50 (Figure 2), and determines whether or not the measured anode voltage value and current value are in the magnetron failure region 53 (Figures 6A-C) based on the measured anode voltage value and current value.

[0064] If the output value and voltage value of the industrial magnetron 10 are in the magnetron failure region 53 (Figures 6A-C) (Yes in step S15), in step S16 the control unit 30 determines whether the output value and voltage value can be moved outside the magnetron failure region 53 while maintaining the output value of the industrial magnetron 10 at the rated output.

[0065] If the output value and voltage value cannot be moved out of the magnetron failure region 53 (FIGS. 6A-6C) in step S16 (No in step S16), the control unit 30 outputs an error message in step S17 and ends the processing of this flow.

[0066] If the output value and voltage value of the industrial magnetron 10 are not in the magnetron failure region 53 (Figures 6A-C) in step S15 above (No in step S15), or if the output value and voltage value can be moved out of the magnetron failure region 53 in step S16 above (Yes in step S16), then in step S18 the control unit 30 determines whether the output value and voltage value of the industrial magnetron 10 are in the good spectrum region 51 (Figures 6A-C).

[0067] If the output value and voltage value of the industrial magnetron 10 are in the good spectrum region 51 (Figures 6A-C) (Yes in step S18), in step S19 the control unit 30 sets the current output value and voltage value of the industrial magnetron 10 as the voltage value and current value to be applied to the anode, and ends the processing of this flow.

[0068] If the output value and voltage value of the sample industrial magnetron are not in the good spectrum region 51 (Figures 6A-C) (No in step S18), in step S20 the control unit 30 reduces the output value of the industrial magnetron 10 to at least half the rated output (for example, 80% of the rated output) (reducing it so that it is not less than half), and then sets the current value to be applied to the anode so that the output value becomes the rated output.

[0069] In step S21, the control unit 30 determines whether the output value and voltage value of the sample industrial magnetron 10 are in the good spectrum region 51 (FIGS. 6A-6C).

[0070] If the output value and voltage value of the sample industrial magnetron are in the good spectrum region 51 (Figures 6A-C) (Yes in step S21), in step S22 the control unit 30 sets the current output value and voltage value of the industrial magnetron 10 as the voltage value and current value to be applied to the anode, and then ends this flow.

[0071] If the output value and voltage value of the industrial magnetron 10 are not in the good spectrum region 51 (Figures 6A-C) (No in step S21), in step S23 the control unit 30 reduces the filament voltage Ef of the industrial magnetron 10 and determines whether or not they have entered the good spectrum region 51 based on the measured filament voltage and current values.

[0072] If the spectrum falls within the good spectrum range (Yes in step S23), the control unit 30 sets the output value and voltage value of the sample industrial magnetron 10 and the voltage value of the filament voltage Ef in step S24, and ends the processing of this flow.

[0073] If the spectrum does not fall within the good spectrum region (No in step S23), in step S25 the control unit 30 provisionally sets the output value and voltage value of the sample industrial magnetron 10 and the voltage value of the filament voltage Ef, and notifies that the spectrum is in the deteriorated spectrum region, i.e., the magnetron failure region 53 (Figures 6A-C), and ends the processing of this flow.

[0074] [Prototype example] A prototype of a sample industrial magnetron 10 will be described. Fig. 9 is a table showing the prototype results of a sample industrial magnetron 10. Fig. 9 shows the specifications of Comparative Example 1, Comparative Example 2, and this example for each item (product name, anode current Ib [mA], anode voltage Eb [kV], other items omitted). In this example, the anode voltage Eb was lowered from the specifications of Comparative Example 2, which had a rated Eb of 7.5 kV, and the anode current Ib was increased accordingly according to the above formula (1), and evaluation was performed with a rated Eb of 8.5 kV. Specifically, in this embodiment, the anode voltage Eb: 8.5±0.3 [kV] of the specifications of Comparative Example 2 is reduced to the anode voltage Eb: 7.5±0.3 [kV], and the anode current Ib: 1700 [mA] of the specifications of Comparative Example 2 is increased to the anode current Ib: 1900 [mA].

[0075] This makes it possible to significantly increase the spectrum-good region 51, as shown by the symbol c in FIGS. 6B-C, and improve the spectrum.

[0076] Fig. 10 is a diagram showing the filament voltage Ef of Comparative Example 2 and this example of the prototype example in Fig. 9. The horizontal axis represents the anode current Ib [mA], and the vertical axis represents the filament voltage Ef [V]. In Fig. 10, the thin dashed line represents the filament voltage Ef of Comparative Example 2, the thick dashed line represents the filament voltage Ef of this example before the filament voltage was lowered, and the solid line represents the new set value of the filament voltage Ef of this example (the value to which the filament voltage Ef was lowered). The evaluation was carried out at −0.5 V and −1.0 V with Ef as the reference voltage during the evaluation of Comparative Example 2.

[0077] In this way, when the anode voltage Eb is reduced to 7.5 kV, the filament voltage Ef can also be reduced, as shown in FIG. 6C, and a synergistic effect can be obtained in that the reduced filament voltage Ef makes the spokes less likely to break.

[0078] 11 is a diagram showing example results of spectrum characteristics when Ib is 600 mA and filament voltages Ef are Ef 3.7 V, Ef 3.2 V, and Ef 2.7 V in the specifications of Comparative Example 1 (Eb 8.9 kV), Comparative Example 2 (Eb 8.5 kV), and this example (Eb 7.5 kV) in FIG. 9. The horizontal axis of each spectrum characteristic shown in FIG. 11 is oscillation frequency [MHz] (grid width is 2 [MHz]), and the vertical axis is oscillation intensity [dB] (grid width is -10 [dB]).

[0079] As shown in Figure 11, when the anode voltage Eb was reduced to 7.5 kV (Eb 7.5 kV) in this example, and the filament voltage Ef was reduced to 2.7 V (when both Eb and Ef were reduced), a sharp spectrum was confirmed at an oscillation frequency of 8 MHz. By sharpening the spectrum waveform, a stable plasma state can be achieved.

[0080] Fig. 12 is a diagram showing a comparison of the spectrum characteristics of the specifications (Eb8.9 kV) of Comparative Example 1 in Fig. 9 and the specifications (Eb7.5 kV) of this example over a wide range of 1 to 10 kW. The horizontal axis of each spectrum characteristic shown in Fig. 12 is the oscillation frequency [MHz] (grid width is 2 [MHz]), and the vertical axis is the oscillation intensity [dB] (grid width is -10 [dB]).

[0081] First, in the spectrum characteristics at 1 kW, both the specifications of Comparative Example 1 (Eb 8.9 kV) and the specifications of this example (Eb 7.5 kV) were NG. Below are the prototype results for a wide spectrum of 2 to 10 kW.

[0082] In the specifications (Eb8.9 kV) of Comparative Example 1 in FIG. 12, four units of 2 kW, 6 kW, 8 kW, and 10 kW were OK. In the specifications (Eb7.5kV) of this embodiment in Fig. 12, all seven of the spectrums from 2kW to 10kW were OK. However, the specifications (Eb7.5kV) of this embodiment had the following waveform adjustment history. (1) In the first prototype, four out of six were OK without waveform adjustment. (2) Of the remaining two that were NG, one was found to be OK after adjusting the waveform. (3) The remaining one, which also failed after waveform adjustment, failed at Ib 400-800mA. It became OK when the filament voltage Ef was further reduced. (4) In the prototypes with an increased number of N (30 in total), Eb was made slightly lower, and all of the 2kW to 10kW units were non-defective.

[0083] [effect] As described above, the industrial magnetron setting device 1 (FIG. 1) of this embodiment is an industrial magnetron setting device that sets the voltage and current values ​​to be applied to the anode of the industrial magnetron 10 (FIG. 1), and is equipped with a control unit 30 that uses a sample industrial magnetron 10 to set an initial value of the voltage value and sets the current value so that the output value of the industrial magnetron 10 becomes the rated output, and a memory unit 40 that stores the voltage and current values ​​set by the control unit 30, and the control unit 30 reduces the voltage value so that the output value becomes half or more of the rated output, and then sets the current value so that the output value becomes the rated output.

[0084] This configuration uses a single magnetron, which reduces the cost of the entire device compared to known devices that use multiple magnetrons, while generating a stable plasma state even when the rated output is changed from low to high.

[0085] Furthermore, during the manufacturing stage, a sample product was used to apply a voltage of about 70% of the conventional voltage to the anode, and a current was applied to the anode so as to output the rated power. While checking the spectrum waveform, the current was changed and the voltage was finely adjusted to prevent disturbances in the spectrum waveform, making it possible to stabilize the plasma state. As a result, it is possible to prevent oscillation stoppages due to abnormal oscillations in industrial magnetrons with high output.

[0086] In the industrial magnetron setting device 1 (FIG. 1), the control unit 30 (FIG. 1) reads out the voltage and current values ​​set using the sample product from the memory unit 40, and sets them to the voltage and current values ​​to be applied to the anode of the industrial magnetron 10 other than the sample product.

[0087] With this configuration, the voltage and current values ​​set using the sample product can be used as resources to be applied to the production of industrial magnetrons other than the sample product.

[0088] In the setting device 1 for industrial magnetrons (FIG. 1), the rated output obtained by setting the voltage and current values ​​of the sample product is set in the range of 2 kW to 10 kW.

[0089] With this configuration, in the specifications of Comparative Example 2 (Eb8.5kV) shown in FIG. 12, a sharp spectrum was confirmed only in the range of 6kW to 10kW and around 2kW, whereas in the specifications of this embodiment (Eb7.5kV) shown in FIG. 12, a sharp spectrum was confirmed over a wide range of 2kW to 10kW.

[0090] In the industrial magnetron setting device 1 (FIG. 1), the control unit 30 (FIG. 1) uses the output value and voltage value of the industrial magnetron 10 (FIG. 1) as parameters for each rated anode voltage to create a spectrum region map 50 that is divided into a good spectrum region 51 where no disturbance occurs in the microwave spectrum waveform, a deteriorated spectrum region 52 where disturbance occurs in the microwave spectrum waveform, and a magnetron failure region 53 where magnetron failure is expected, and the memory unit 40 stores the created spectrum region map 50.

[0091] With this configuration, applying a high voltage to the anode and a low current disrupts the microwave spectrum and makes the plasma unstable. We confirmed that this can be improved by reducing the voltage applied to the anode and increasing the current. Using the spectrum region map 50, the settings for the output and voltage values ​​of an industrial magnetron can be quantitatively and visually understood from a spectrum perspective. It was also found that the voltage applied to the anode should be roughly 50% of that of Comparative Example 2 shown in Figure 11.

[0092] In the setting device 1 (FIG. 1) for an industrial magnetron, the control unit 30 (FIG. 1) uses a sample of the industrial magnetron 10 (FIG. 1), and by referring to a first spectrum region map 50 (FIG. 6B) created based on the anode voltage Eb of the first rated output (FIG. 6B: Eb 8.5 kV), sets an initial value of the voltage value within a good spectrum region 51 of the first spectrum region map 50 (FIG. 6B), sets a current value so that the output value of the industrial magnetron 10 becomes the rated output (FIG. 6B: Eb 8.5 kV), and If the output is not within the good spectrum region 51 of the first spectrum region map 50 (FIG. 6B), the voltage value is set within the good spectrum region 51 of the second spectrum region map 50 (FIG. 6C) by reference to the second spectrum region map 50 (FIG. 6C) created based on the anode voltage of the second rated output (FIG. 6C: Eb 7.5 kV) created by lowering the anode voltage Eb of the first rated output (FIG. 6B: Eb 8.5 kV), and the current value is set so that the output value of the industrial magnetron 10 becomes the rated output (FIG. 6C: Eb 7.5 kV).

[0093] With this configuration, it is possible to quantitatively and visually grasp the settings of the output value and voltage value of the industrial magnetron from the viewpoint of spectrum by using the spectrum region map 50. For example, if the rated output is not within the good spectrum region 51 of the first spectrum region map 50 (FIG. 6B), it is possible to set the voltage value within the good spectrum region 51 of the second spectrum region map 50 (FIG. 6C) for the second rated output (FIG. 6C: Eb 7.5 kV), and to set the current value so that the output value of the industrial magnetron 10 becomes the rated output (FIG. 6C: Eb 7.5 kV).

[0094] In the setting device 1 (FIG. 1) for an industrial magnetron, when the anode voltage Eb of the second rated output (FIG. 6C: Eb 7.5 kV) is used, the control unit 30 (FIG. 1) maintains the rated output by increasing the anode current Ib by the amount that the anode voltage Eb of the first rated output (FIG. 6B: Eb 8.5 kV) is reduced.

[0095] This configuration makes it possible to quantitatively and visually set the output and voltage values ​​of an industrial magnetron from a spectrum perspective using the spectral region map 50, enabling the application of an optimal rated output anode voltage. Furthermore, since the rated output is maintained by increasing the anode current to compensate for the decrease in anode voltage, a stable plasma state can be generated even when the rated output is changed from low to high while optimizing device operation, while still maintaining the rated output.

[0096] The industrial magnetron setting device 1 (FIG. 1) is provided with a measurement unit (anode voltmeter 21, anode ammeter 22, filament voltmeter 23, filament ammeter 24) (FIG. 1) that measures the voltage and current values ​​of the filament and the voltage and current values ​​of the anode of the industrial magnetron 10, and the control unit 30 (FIG. 1) refers to a spectrum region map 50 (FIGS. 6A-6C) in the memory unit 40 based on the measurement results of the measurement unit, and reduces the filament voltage Ef within a good spectrum region 51.

[0097] With this configuration, lowering the filament voltage Ef reduces the electron density, suppressing collisions between electrons and making the spokes less likely to break. This makes it possible to generate a stable plasma state even when changing the rated output from low to high.

[0098] In the industrial magnetron setting device 1 (FIG. 1), when the filament voltage Ef cannot be lowered within the good spectrum region 51 of the first spectrum region map 50 (FIG. 6B) created based on the anode voltage of the first rated output (FIG. 6B: Eb 8.5 kV), the control unit 30 (FIG. 1) refers to the second spectrum region map 50 (FIG. 6C) created based on the anode voltage of the second rated output (FIG. 6C: Eb 7.5 kV) created by lowering the anode voltage of the first rated output (FIG. 6B: Eb 8.5 kV), and lowers the filament voltage Ef within the good spectrum region 51 of the second spectrum region map 50 (FIG. 6C).

[0099] This configuration makes it possible to quantitatively and visually set the filament voltage Ef from the viewpoint of spectrum. There have been no previous studies examining the filament voltage Ef from the viewpoint of generating a stable plasma state, much less considering changing the first rated output (Figure 6B: Eb 8.5 kV) to the second rated output (Figure 6C: Eb 7.5 kV) in order to lower the filament voltage Ef. Lowering the filament voltage Ef makes it possible to generate an even more stable plasma state.

[0100] The present invention is not limited to the configuration described in the above embodiment, and the configuration can be modified as appropriate without departing from the gist of the present invention described in the claims. Here, the method of lowering the filament voltage Ef is used in combination with the method of maintaining the rated output by increasing the anode current Ib to compensate for the decrease in the anode voltage Eb, but it is also possible to apply only one of these methods. Also, the term "sample product" should not be interpreted narrowly. One of the mass-produced products (a predetermined number) may be treated as a sample product.

[0101] The above-described embodiments have been described in detail to clearly explain the present invention, and are not necessarily limited to those including all of the described configurations. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, or to add the configuration of one embodiment to the configuration of another embodiment. Furthermore, it is possible to add, delete, or replace part of the configuration of each embodiment with other configurations. [Explanation of symbols]

[0102] 1 Industrial magnetron setting device 10 Industrial Magnetron 20 High voltage power supply section 21 Anode voltmeter (measurement section) 22 Anode current meter (measurement section) 23 Filament voltmeter (measurement section) 24 Filament ammeter (measurement section) 30 Control Unit 40 Storage section 50 Spectral Region Maps 51 Good spectrum area 52 Spectrum Deterioration Area 53 Magnetron failure area 151 Cathode filament (cathode) 152 Anode Vein (Vane) (Anode) Eb anode voltage Ib anode current Ef filament voltage S1 Step of creating a spectrum region map, which is divided into a good spectrum region where no disturbance occurs in the microwave spectrum waveform, a poor spectrum region where disturbance occurs in the microwave spectrum waveform, and a magnetron failure region where magnetron failure is expected, using the output value and voltage value of the industrial magnetron as parameters for each rated anode voltage. S20: Reducing the voltage value so that the output value is at least half of the rated output, and then setting the current value so that the output value is the rated output. S24: A step of lowering the filament voltage within the good spectrum region based on the measurement result and referring to the spectrum region map in the memory.

Claims

1. An industrial magnetron setting device for setting a voltage value and a current value to be applied to an anode of the industrial magnetron, a control unit that uses a sample of the industrial magnetron to set an initial value of the voltage value and sets the current value so that the output value of the industrial magnetron becomes a rated output; a storage unit that stores the voltage value and the current value set by the control unit, The control unit reduces the voltage value so that the output value becomes half or more of the rated output, and then sets the current value so that the output value becomes the rated output. An industrial magnetron setting device characterized by:

2. The control unit reads out the voltage value and the current value set using the sample product from the storage unit, and sets the voltage value and the current value to be applied to the anode of the industrial magnetron other than the sample product.

2. The setting device for an industrial magnetron according to claim 1.

3. The rated output obtained by setting the voltage value and the current value of the sample product is set in the range of 2 kW to 10 kW.

2. The setting device for an industrial magnetron according to claim 1.

4. the control unit creates a spectrum region map, for each rated anode voltage, using the output value and voltage value of the industrial magnetron as parameters, which is divided into a good spectrum region where no disturbance occurs in the microwave spectrum waveform, a deteriorated spectrum region where disturbance occurs in the microwave spectrum waveform, and a magnetron failure region where magnetron failure is expected; The storage unit stores the created spectral region map.

2. The industrial magnetron setting device according to claim 1.

5. The control unit uses a sample of the industrial magnetron, references a first spectrum region map, which is the spectrum region map created based on an anode voltage of a first rated output that is the rated output, and sets an initial value of the voltage value within the good spectrum region of the first spectrum region map, and sets the current value so that the output value of the industrial magnetron becomes the first rated output; If the rated output is not within the good spectrum region of the first spectrum region map, a second spectrum region map is referenced, which is the spectrum region map created based on the anode voltage of a second rated output created by lowering the anode voltage of the first rated output, and the voltage value is set within the good spectrum region of the second spectrum region map, and the current value is set so that the output value of the industrial magnetron becomes the second rated output.

5. The setting device for an industrial magnetron according to claim 4.

6. When the anode voltage of the second rated output is used, the control unit maintains the second rated output by increasing the anode current by an amount corresponding to the reduction in the anode voltage of the first rated output.

6. The setting device for an industrial magnetron according to claim 5.

7. a measuring unit for measuring a voltage value and a current value of a filament of the industrial magnetron and a voltage value and a current value of an anode; The control unit refers to the spectrum region map in the storage unit based on the measurement result of the measurement unit, and reduces the filament voltage within the good spectrum region.

5. The setting device for an industrial magnetron according to claim 4.

8. When the filament voltage cannot be lowered within the good spectrum region of the first spectrum region map created based on the anode voltage of the first rated output, the control unit refers to a second spectrum region map created based on the anode voltage of a second rated output created by lowering the anode voltage of the first rated output, and lowers the filament voltage within the good spectrum region of the second spectrum region map.

6. The setting device for an industrial magnetron according to claim 5.

9. A method for setting an industrial magnetron, which sets a voltage value and a current value to be applied to an anode of the industrial magnetron, comprising: Using a sample of the industrial magnetron, an initial value of the voltage value is set, and the current value is set so that the output value of the industrial magnetron becomes a rated output; a control step of reducing the voltage value so that the output value is equal to or greater than half of the rated output, and then setting the current value so that the output value is equal to the rated output; a storage step of storing the set voltage value and current value in a storage unit; A method for setting an industrial magnetron.

10. In the control step, the voltage value and the current value set using the sample product are read from the storage unit, and are set to the voltage value and the current value to be applied to the anode of the industrial magnetron other than the sample product.

10. The method of claim 9, wherein the setting of an industrial magnetron is performed.

11. In the control step, a spectrum region map is created for each rated anode voltage, using the output value and voltage value of the industrial magnetron as parameters, the spectrum region map being divided into a good spectrum region where no disturbance occurs in the microwave spectrum waveform, a deteriorated spectrum region where disturbance occurs in the microwave spectrum waveform, and a magnetron failure region where magnetron failure is expected; In the storing step, the created spectral region map is stored.

10. The method of claim 9, wherein the setting of an industrial magnetron is performed.

12. In the control step, a sample of the industrial magnetron is used, and a first spectrum region map is referenced, which is the spectrum region map created based on an anode voltage of a first rated output that is the rated output, to set an initial value of the voltage value within the good spectrum region of the first spectrum region map, and set the current value so that the output value of the industrial magnetron becomes the first rated output; If the rated output is not within the good spectrum region of the first spectrum region map, a second spectrum region map is referenced, which is the spectrum region map created based on the anode voltage of a second rated output created by lowering the anode voltage of the first rated output, and the voltage value is set within the good spectrum region of the second spectrum region map, and the current value is set so that the output value of the industrial magnetron becomes the second rated output.

12. The method of claim 11, wherein the setting of an industrial magnetron is performed.

13. In the control step, when the anode voltage of the second rated output is used, the anode current is increased by an amount corresponding to the reduction in the anode voltage of the first rated output, thereby maintaining the second rated output.

13. The method of claim 12, wherein the setting of an industrial magnetron is performed.

14. a measuring step of measuring a voltage value and a current value of a filament of the industrial magnetron and a voltage value and a current value of an anode; In the control step, the filament voltage is reduced within the good spectrum region by referring to the spectrum region map in the storage unit based on the measurement result in the measurement step.

12. The method of claim 11, wherein the setting of an industrial magnetron is performed.

15. In the control step, if the filament voltage cannot be lowered within the good spectrum region of the first spectrum region map created based on the anode voltage of the first rated output, the filament voltage is lowered within the good spectrum region of the second spectrum region map by referring to a second spectrum region map created based on the anode voltage of a second rated output created by lowering the anode voltage of the first rated output.

13. The method of claim 12, wherein the setting of an industrial magnetron is performed.

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