TWI733215B - Power supply device for laser device - Google Patents

Abstract

[Question] Provide a laser device that improves reliability. [Solution] The high-frequency power supply (400) applies a high-frequency voltage (V _RF ) to the resonant circuit (210) including a pair of discharge electrodes (202, 204) of the capacitor. The overvoltage suppression circuit (500) suppresses the overvoltage between both ends of the resonance circuit (210). If the abnormality detector (600) detects an abnormality, the application _{of the high-frequency voltage (V RF} ) from the high-frequency power supply (400) is stopped.

Description

Power supply device for laser device

The present invention relates to a power supply device.

As industrial processing tools, laser processing devices are widely used. Regarding the laser processing device, a high-output gas laser such as a _{CO 2 laser is used.} Fig. 1 is a block diagram of a laser device 100R. The laser device 100R includes a laser resonator 200 and a power supply device 250R. The laser resonator 200 includes a pair of discharge electrodes 202 and 204, a total reflection mirror 206, and a partial reflection mirror 208.

A pair of discharge electrodes 202 and 204 are arranged in a gas cavity filled with a laser medium gas such as _{CO 2.} There is a capacitance C between the pair of discharge electrodes 202 and 204. The capacitor C and the inductance L (inductance element or parasitic inductance) form a resonance circuit 210 _{having a resonance frequency f RES.}

The power supply device 250R applies a high-frequency voltage V _RF to the resonance circuit 210. The frequency f _{RF of the} high-frequency voltage V _RF (hereinafter referred to as the synchronization frequency) is set in the vicinity _{of the frequency f RES of the resonance circuit.} By applying the high-frequency voltage V _RF , a discharge current flows between the pair of discharge electrodes 202 and 204. The laser dielectric gas is excited by the discharge current to form an inverted distribution. The excitation light moves back and forth in the optical resonator formed by the total reflection mirror 206 and the partial reflection mirror 208, and is amplified by passing through the laser medium gas. A part of the amplified light is taken out from the partial reflection mirror 208 as an output.

The power supply device 250R includes a DC power supply 300 that generates a stabilized DC voltage V _DC and a high-frequency power supply 400 that converts the DC voltage V _DC into a high-frequency voltage V _RF . [Prior Technical Documents] [Patent Documents]

[Patent Document 1] Japanese Patent Application Publication No. 2018-39032 [Patent Document 2] Japanese Patent Application Publication No. 2015-32746

[The problem to be solved by the invention]

The inventors of the present invention conducted research on the laser device 100R of FIG. 1 and found the following problems.

If poor contact or the like occurs in the discharge electrode 202 or 204, the operation is performed in an open state. In the open state, the capacitance C becomes very small, so the resonance frequency of the resonance circuit becomes a very high value f _RES '. In this state, if the high-frequency voltage V _{RF of the synchronous frequency f 0} (f ₀ <f _RES ') is continuously applied, a very high voltage exceeding the amplitude of the high-frequency voltage V _{RF will be} generated at the resonance frequency f _{RES '} . If this high voltage is applied to a semiconductor element (that is, a power transistor) inside the high-frequency power supply 400, the reliability is reduced.

The present invention was completed under relevant conditions, and one of the illustrative purposes of one aspect is to provide a laser device with improved reliability. [Means to solve the problem]

One aspect of the present invention relates to a power supply device for driving a laser resonator including a pair of discharge electrodes. The power supply device is equipped with: a high-frequency power supply, which applies a high-frequency voltage to a resonance circuit including a pair of discharge electrodes, and an over-voltage suppression circuit, which suppresses the overvoltage between the two ends of the resonance circuit or the internal nodes of the high-frequency power supply. Voltage; switch, which is connected in series with the overvoltage suppression circuit; and an abnormality detector, which turns on the switch if an abnormality is detected.

The "abnormality" mentioned here is an abnormality that may cause overvoltage in the power supply device. By providing the overvoltage suppression circuit, when the resonance frequency of the resonance circuit greatly deviates from the design value, the overvoltage can be suppressed, thereby being able to protect the semiconductor components included in the high-frequency power supply. In addition, by closing the switch in advance under the condition that no overvoltage is generated, leakage current can be prevented from flowing through the overvoltage suppression circuit, thereby suppressing the interference caused by the leakage current.

The frame of the laser resonator can also be grounded via a ground wire. The anomaly detector can also detect anomalies based on the current flowing through the ground wire.

The frame of the laser resonator is grounded via a ground wire, and the anomaly detector can also detect anomalies based on the potential of the frame.

The power supply device may also be equipped with: if an abnormality is detected by the abnormality detector, it will notify an external notification organization.

The high-frequency power supply may also include an inverter and a transformer with a primary winding connected to the output terminal of the inverter and a secondary winding connected to the laser resonator. The overvoltage suppression circuit can also be connected to the primary winding of the transformer.

The overvoltage suppression circuit may also include at least one of a voltage suppressor, a surge protection device, and a gas arrester (surge arrester).

The overvoltage suppression circuit may also include a plurality of elements connected in series. When the capacitance of each element is large, by connecting them in series, the capacitance of the overvoltage suppression circuit can be reduced.

The overvoltage suppression circuit may also include a capacitor having a capacitance of 1/10 or less of the capacitance of a pair of discharge electrodes. At this time, the capacitor becomes a load, so it is possible to prevent the resonance frequency from becoming too high, and it is possible to suppress overvoltage.

The overvoltage suppression circuit can also include an LCR load. At this time, even if the discharge electrode becomes an open state due to an abnormality, the LCR load can prevent the resonance frequency from becoming too high, thereby suppressing overvoltage.

In addition, among methods, devices, systems, etc., it is equally effective as an aspect of the present invention to replace any combination of the above constituent elements or the constituent elements or expression forms of the present invention with each other. [Effects of the invention]

According to one aspect of the present invention, the reliability of the laser device can be improved.

Hereinafter, according to the preferred embodiments of the present invention, the present invention will be described with reference to the drawings. The same or equivalent constituent elements, members, and processes shown in the various drawings are denoted by the same reference numerals, and repeated descriptions are appropriately omitted. In addition, the embodiment is merely an illustration and does not limit the invention, and all the features or combinations described in the embodiment do not necessarily limit the essence of the invention.

FIG. 2 is a block diagram of the laser device 100 according to the embodiment. The laser device 100 includes a laser resonator 200 and a power supply device 250.

In FIG. 2, the laser resonator 200 is shown as an equivalent circuit. A capacitor C and a resistance component R are included between the pair of discharge electrodes 202 and 204. The capacitor C and the inductance L form a resonance circuit 210 together. Let the resonance frequency of the resonance circuit 210 be f _RES . The inductance L includes at least one of an inductance component and a parasitic inductance of a wiring or a substrate.

The power supply device 250 applies a high-frequency voltage V _RF to the resonance circuit 210. The frequency f _{RF of the} high-frequency voltage V _RF (hereinafter referred to as the synchronization frequency) is set in the vicinity _{of the frequency f RES of the resonance circuit.} By applying the high-frequency voltage V _RF , a discharge current flows between the pair of discharge electrodes 202 and 204. The laser dielectric gas is excited by the discharge current to form an inverted distribution.

The power supply device 250 includes a DC power supply 300, a high-frequency power supply 400, an overvoltage suppression circuit 500, a switch SW1, an abnormality detector 600, and a notification mechanism 610. Regarding the DC power supply 300, its output terminal is connected to a pair of DC links 310, and the DC link 310 generates a DC voltage (also referred to as a DC link voltage) V _DC that is stabilized to a predetermined voltage level.

The input of the high frequency power supply 400 is connected to the DC link 310 to receive the DC link voltage V _DC . The high-frequency power supply 400 generates a high-frequency voltage V _RF having the same frequency (synchronization frequency) f _{RF as the resonance frequency f RES} and supplies it to the laser resonator 200. The composition of the high-frequency power supply 400 is not limited, and it can include an H-bridge circuit (inverter) 402 that _{converts a DC voltage V DC} into an AC voltage V _AC and a step-up transformer 404 that boosts _{the output voltage V AC of the H-bridge circuit 402} .

The overvoltage suppression circuit 500 is configured to be able to suppress an overvoltage between both ends of the resonance circuit 210 or an internal node of the high-frequency power supply. In FIG. 2, regarding the overvoltage suppression circuit 500, the connection node of the H bridge circuit 402 and the step-up transformer 404 is connected, so that the overvoltage of the voltage on the primary side of the step-up transformer 404 can be suppressed.

In order to block the current path of the overvoltage suppression circuit 500, the switch SW1 and the overvoltage suppression circuit 500 are arranged in series.

If the abnormality detector 600 detects the abnormality of the laser device 100, it determines the abnormality detection signal S _ABN and turns on the switch SW1. The "abnormality" referred to here is an abnormality that can cause overvoltage to be generated in the power supply device 250. In other words, an abnormality that shifts the resonance frequency to a value higher than the design value. For example, the discharge electrodes 202 and 204 have poor contact and the inductance L Disconnection, disconnection of wiring such as connection, disconnection (disconnection) of wiring, or increase in impedance caused by deterioration. Further, the power supply device 250 can be concluded that the abnormality detection signal S _ABN after an abnormality occurs, the abnormality may appear in the sign of the abnormality detection signal to determine the phase of S _ABN.

The notification mechanism 610 notifies the outside of the abnormality detection based on the abnormality detector 600. For example, the notification mechanism 610 may also be a notification mechanism that directly notifies the user such as a buzzer, a lamp, or a display.

Alternatively, the notification mechanism 610 may also be an interface connected to a controller on the system side that controls a buzzer, a lamp, and a display. At this time, the notification mechanism 610 may also indirectly notify the user of the occurrence of the abnormality. At this time, the controller on the system side uses the notification of the occurrence of the abnormality as a trigger to implement appropriate protection processing at an appropriate timing.

The above is the basic configuration of the power supply device 250. Next, the operation will be described.

If an abnormality (or a sign) occurs in the laser device 100, the abnormality detector 600 determines the abnormality detection signal S _ABN and turns on the switch SW1. Thereby, the overvoltage suppression circuit 500 is connected to the high-frequency power supply 400, and the overvoltage between the nodes to which the overvoltage suppression circuit 500 is connected is suppressed.

On the other hand, when the laser device 100 is in a normal state, the abnormality detector 600 negates the abnormality detection signal S _ABN and closes the switch SW1. Therefore, the overvoltage suppression circuit 500 is disconnected from the high-frequency power supply 400.

The above is the operation of the power supply device 250. According to the power supply device 250, by providing the overvoltage suppression circuit 500, when the resonance frequency f _{RES of the} resonance circuit 210 greatly deviates from the design value, the overvoltage can be suppressed, and the semiconductor components included in the high frequency power supply 400 and the like can be protected. Also, by closing the switch SW1 in advance under the condition that no overvoltage is generated, it is possible to prevent leakage current from flowing through the overvoltage suppression circuit 500, thereby suppressing interference caused by the leakage current.

The present invention is grasped as the block diagram or circuit diagram of FIG. 2 or related to various devices and methods derived from the above description, and is not limited to a specific structure. Hereinafter, not to limit the scope of the present invention, but to help understand the essence or action of the present invention and clarify the same, more specific configuration examples or embodiments are described.

‧About the abnormality detector 600 If the detection speed of the abnormality detector 600 is slow, the opening of the switch SW1 is delayed, and overvoltage is generated during the delay period, which is not preferable. _{Therefore, it is required for the abnormality detector 600 to determine the abnormality detection signal S ABN} earlier than the timing at which the overvoltage suppression circuit 500 should operate effectively (that is, the timing at which the overvoltage is actually generated). Among them, the high-speed abnormality detector 600 will be described below.

3(a) and 3(b) are circuit diagrams showing examples of the configuration of the abnormality detector 600. FIG. The laser resonator 200 is covered by a metal housing (gas chamber) 220, and the housing 220 is grounded via a ground wire 222.

The abnormality detector 600 of FIG. 3(a) determines whether there is an abnormality based on the current Ix flowing through the ground wire 222. More specifically, if the amplitude of the current Ix flowing through the ground wire exceeds a predetermined critical value, it can be determined as abnormal.

The abnormality detector 600 of FIG. 3(b) determines whether there is an abnormality based on the grounding potential Vx of the housing 220. More specifically, if the amplitude of the potential Vx exceeds a predetermined critical value, it can be determined to be abnormal.

The above is an example of the configuration of the abnormality detector 600. Next, the operating principle of the abnormality detector 600 will be described. Parasitic capacitance Cp exists between the discharge electrode 202 and the frame 220 and between the discharge electrode 204 and the frame 220. When the laser resonator 200 is normal, _{the current of the designed resonance frequency f RES} flows through the laser resonator 200 (between the electrodes 202 and 204), and the influence of the parasitic capacitance Cp can be ignored. At this time, the current Ix flowing through the parasitic capacitance Cp and the ground line 222 is substantially zero, and the potential Vx of the frame 220 is substantially equal to the ground voltage.

If the wiring connected to the discharge electrode 202 or the discharge electrode 204 is disconnected or the impedance increases, the resonance frequency of the resonance circuit 210 becomes higher than the design value, and a high-frequency current flows. The high-frequency current flows through the ground line 222 via the parasitic capacitance Cp having a small capacitance value. Thereby, the potential Vx of the frame 220 becomes non-zero.

According to the abnormality detector 600 of Fig. 3(a) and Fig. 3(b), the displacement of the resonance frequency of the resonant circuit 210 can be detected at a high speed, so that the overvoltage can be actually generated inside the power supply device 250 (or even if it has already been generated). Immediately) Turn on switch SW1.

In addition, the method of abnormality detection by the abnormality detector 600 is not limited to this. Instead of using a method with low responsiveness, the critical value for abnormality determination may be strictly set.

4(a) to 4(d) are circuit diagrams showing configuration examples of the overvoltage suppression circuit 500. FIG. The overvoltage suppression circuit 500 of FIG. 4(a) includes a gas arrester 502. If the voltage between the terminals of the gas arrester 502 exceeds the operation start voltage, the gas arrester 502 enters a short-circuit state, and the voltage ΔV between both ends of the overvoltage suppression circuit 500 is suppressed.

Among them, the capacitance between the two ends of the overvoltage suppression circuit 500 is preferably less than 1/5 of the capacitance of a pair of discharge electrodes. The reason is that if the capacitance of the overvoltage suppression circuit 500 is too large, the resonance frequency f _{RES of} the resonance circuit 210 is shifted, which affects the circuit operation. From this point of view, as shown in FIG. 4(a), if the overvoltage suppression circuit 500 is composed of a single gas arrester 502, the capacitance may be too large.

In such a case, as shown in FIG. 4(b), a plurality of overvoltage suppression elements (surge protection elements) may be connected in series. Thereby, the capacitance between both ends of the overvoltage suppression circuit 500 becomes a combined capacitance of the respective capacitances of the plurality of overvoltage suppression elements, and therefore can be made smaller than the capacitance of each overvoltage suppression element.

In more detail, the overvoltage suppression circuit 500 of FIG. 4(b) includes a gas arrester 502 and a varistor 504 connected in series. In this configuration, when a high voltage ΔV is applied between both ends of the overvoltage suppression circuit 500, the voltage between the terminals of the gas arrester 502 exceeds the operation start voltage and becomes a short-circuit state, and the high voltage ΔV is applied to the varistor 504. As a result, the current flows according to the I-V characteristic of the varistor 504, and the high voltage ΔV can be suppressed. A general overvoltage suppression element can be used instead of the varistor 504, for example, an SPD (Zinc Oxide Lightning Arrester) or a transient absorber (transorb) can also be used.

The overvoltage suppression circuit 500 of FIGS. 4(a) and 4(b) operates in response to overvoltage, but it is not limited to this. The overvoltage suppression circuit 500 can also be used to prevent the generation of the laser resonator 200 Open the circuit of overvoltage in abnormal state. More specifically, at the synchronous frequency f _RF , the overvoltage suppression circuit 500 has a sufficiently higher impedance than the resonance circuit 210, and can also have a lower impedance at a frequency _{higher than the synchronous frequency f RF.} The overvoltage suppression circuit 500 of FIG. 4(c) includes a capacitor 506. The capacitance of the capacitor 506 is 1/5 or less of the capacitance of the pair of discharge electrodes 202 and 204, preferably 1/10 or less. Even if an open abnormality occurs, the capacitor 506 remains as a load, so it is possible to prevent the resonance frequency from becoming too high, and it is possible to suppress overvoltage.

The overvoltage suppression circuit 500 of FIG. 4(d) includes an LCR load circuit. Even in an open state, the LCR load can prevent the resonance frequency from becoming too high, thereby suppressing overvoltage.

Furthermore, the overvoltage suppression circuit 500 may also be a structure in which several circuits illustrated in FIGS. 4(a) to 4(d) are connected in parallel.

FIG. 5 is a circuit diagram showing a specific configuration example of the power supply device 250. As shown in FIG. A control signal (excitation signal) S1 indicating a light-emitting period (excitation period) and a stop period is input to the laser device 100, and an intermittent operation is performed according to the excitation signal S1. For example, the excitation signal S1 is a pulse signal with a repetition frequency of about several kHz and a duty ratio of about 5%.

The high-frequency power supply 400 includes an H-bridge circuit (full-bridge circuit) 402 and a step-up transformer 404. The high-frequency power supply 400 includes a system of a group 401 of two H-bridge circuits 402 and a step-up transformer 404, and these are connected in parallel. Of course, the group 401 may be constituted by only one system. When the excitation signal S1 indicates the level of the excitation interval (for example, the high level), the H bridge circuit 402 switches and applies an AC voltage V _{AC to the} primary winding of the step-up transformer 404. The switching frequency of the H-bridge circuit 402 is the synchronization frequency f _RF , and is set to about 2 MHz, for example. As a result, the high-frequency voltage V _{RF that boosts the AC voltage V AC} is generated in the secondary winding of the step-up transformer 404.

The DC power supply 300 includes a capacitor bank 302 and a charging circuit 304. The capacitor bank 302 is provided between the DC links 306. The charging circuit 304 charges the capacitor bank 302 and constantly maintains the voltage V _{DC of the} capacitor bank 302.

During the excitation interval, the H-bridge circuit 402 performs a switching action, thereby releasing the energy (charge) stored in the capacitor bank 302, and the voltage level of the _{DC voltage V DC drops.} The charging circuit 304 supplies a charging current to the capacitor bank 302 to compensate for the drop in the voltage level of the _{DC voltage V DC.} That is, the DC power supply 300 also performs intermittent operation in synchronization with the excitation signal S1.

Furthermore, the DC power supply 300 may also be constituted by a DC/DC converter that also includes an excitation period and operates stably.

(use) Next, the use of the laser device 100 will be described. FIG. 6 is a diagram showing a laser processing device 900 equipped with the laser device 100. As shown in FIG. The laser processing device 900 irradiates the target 902 with laser pulses 904 to process the target 902. The type of the object 902 is not particularly limited, and the type of processing includes punching (drilling), cutting, etc., but it is not limited to this.

The laser processing device 900 includes a laser device 100, an optical system 910, a control device 920, and a stage 930. The object 902 is placed on the stage 930 and fixed as necessary. The stage 930 positions the object 902 according to the position control signal S2 from the control device 920, and scans the object 902 and the irradiation position of the laser pulse 904 relatively. The stage 930 can be 1-axis, 2-axis (XY), or 3-axis (XYZ).

The laser device 100 oscillates according to the trigger signal (excitation signal) S1 from the control device 920 to generate a laser pulse 906. The optical system 910 irradiates the target 902 with laser pulses 906. The configuration of the optical system 910 is not particularly limited, and can include a mirror group for guiding the beam to the object 902, a lens or an aperture for beam shaping, and the like.

The control device 920 collectively controls the laser processing device 900. Specifically, the control device 920 outputs the excitation signal S1 to the laser device 100 intermittently. In addition, the control device 920 generates a position control signal S2 for controlling the stage 930 based on the data (recipe) describing the processing.

In the foregoing, the present invention has been described based on the embodiments. This embodiment is an example, and various modifications can be formed according to the combination of the constituent elements or the processing processes, and these modifications are also within the scope of the present invention and are understood by those skilled in the art. Hereinafter, these modified examples will be described.

Several modifications regarding the configuration of the overvoltage suppression circuit will be described. In FIG. 2, the overvoltage suppression circuit 500 is connected between the H-bridge circuit 402 and the step-up transformer 404, but it is not limited to this. FIGS. 7(a) and 7(b) are diagrams showing modified examples of the arrangement of the overvoltage suppression circuit 500. FIG.

As shown in FIG. 7(a), the overvoltage suppression circuit 500 and the switch SW1 can also be provided on the output node of the high-frequency power supply 400, that is, on the secondary side of the step-up transformer 404. Thereby, the overvoltage of the voltage VRF on the secondary side is suppressed, and furthermore, the overvoltage on the primary side can be suppressed.

As shown in FIG. 7(b), the set of the overvoltage suppression circuit 500 and the switch SW1 and the switches (transistors) MH and ML constituting the H-bridge circuit 402 may be respectively arranged in parallel.

The overvoltage suppression circuit 500 and the switch SW1 can also be provided on the laser resonator 200 side.

Several modifications of the abnormality detection method based on the abnormality detector are also described.

The abnormality detector can also determine abnormalities based on the presence or absence of the output light of the laser device. When the laser device does not emit light (or when the amount of light decreases), it can be judged as abnormal.

The abnormality detector can also determine the abnormality based on the current component of the resonance frequency. It is also possible to monitor the current flowing through the load (resonance circuit) or the output terminal of the high-frequency power supply, and extract the components of the resonance frequency from the detected value. If the current at the resonance frequency is small, it is judged as abnormal.

The abnormality detector can also determine abnormalities based on current components other than the resonance frequency. It is also possible to monitor the current flowing through the load (resonance circuit) or the output terminal of the high-frequency power supply, and extract components other than the resonance frequency from the detected value. When the current other than the resonance frequency is large, it is determined to be abnormal.

The abnormality detector can also determine the abnormality based on the drop range of the input voltage of the high-frequency power supply after transmission. If the laser emits normally, the charge stored in the output capacitor (capacitor bank) of the DC power supply is discharged and the DC voltage drops. Therefore, by monitoring the voltage of the capacitor bank, if the voltage drop width is small, it can be judged as abnormal.

The anomaly detector can also determine anomalies based on interference at a frequency higher than the resonance frequency. When the current becomes a high frequency, high-frequency radiation interference or conduction interference increases. The antenna is used to detect the interference, and when the interference increases, it can be judged as abnormal.

The abnormality detector can also determine abnormality based on the voltage between a pair of discharge electrodes. Although a high-frequency voltage is applied, when a sufficient voltage is not detected between both ends of the resonance circuit, it can be judged as abnormal.

According to the embodiment, the present invention has been described using specific sentences, but the embodiment only represents one aspect of the principle and application of the present invention. In the embodiment, within the scope of the idea of the present invention specified in the technical solution, it is allowed Multiple modifications or configuration changes.

100: Laser device 200: Laser resonator 202, 204: discharge electrode 206: Total reflection mirror 208: Partial reflector 210: Resonance circuit 250: power supply unit 300: DC power supply 302: Capacitor Bank 304: charging circuit 400: high frequency power supply 402: H bridge circuit 404: step-up transformer 500: Overvoltage suppression circuit 502: Gas arrester 504: Varistor 600: Anomaly Detector 610: Notifying Agency

Figure 1 is a block diagram of the laser device. Fig. 2 is a block diagram of a laser device according to an embodiment. In Fig. 3, Figs. 3(a) and 3(b) are circuit diagrams showing configuration examples of an abnormality detector. In Fig. 4, Figs. 4(a) to 4(d) are circuit diagrams showing configuration examples of an overvoltage suppression circuit. Fig. 5 is a circuit diagram showing a specific configuration example of the power supply device. Fig. 6 is a diagram showing a laser processing device equipped with a laser device. In Fig. 7, Figs. 7(a) and 7(b) are diagrams showing modified examples of the arrangement of the overvoltage suppression circuit.

200: Laser resonator

202, 204: discharge electrode

210: Resonance circuit

250: power supply unit

300: DC power supply

310: DC chain

400: high frequency power supply

402: H bridge circuit

404: step-up transformer

500: Overvoltage suppression circuit

600: Anomaly Detector

610: Notifying Agency

C: Capacitance

L: Inductance

R: Resistance component

S _ABN : Abnormal detection signal

SW1: switch

V _DC : DC voltage (DC link voltage)

V _RF : high frequency voltage

Claims (5)

A power supply device that drives a laser resonator including a pair of discharge electrodes, and is characterized in that it has: High-frequency power supply, which applies high-frequency voltage to the resonant circuit including the capacitor of the aforementioned pair of discharge electrodes; Overvoltage suppression circuit, which suppresses the overvoltage between the two ends of the aforementioned resonance circuit or the internal node of the aforementioned high-frequency power supply; A switch, which is arranged in series with the aforementioned overvoltage suppression circuit; and The abnormality detector turns on the aforementioned switch if an abnormality is detected. The power supply device as described in item 1 of the scope of patent application, wherein: The frame of the aforementioned laser resonator is grounded via a ground wire; The abnormality detector detects the abnormality based on the current flowing through the ground wire. The power supply device as described in item 1 of the scope of patent application, wherein: The frame of the aforementioned laser resonator is grounded via a ground wire, The abnormality detector detects the abnormality based on the potential of the housing. Such as the power supply device described in any one of items 1 to 3 in the scope of patent application, which also has: The notification mechanism is to notify the outside if the abnormality detector detects an abnormality. The power supply device described in any one of items 1 to 3 in the scope of patent application, wherein: The aforementioned high-frequency power supplies include: Inverter; and A transformer having a primary winding connected to the output terminal of the aforementioned inverter and a secondary winding connected to the aforementioned laser resonator; The overvoltage suppression circuit is connected to the primary winding of the transformer.

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