JPH08214549A - Power source - Google Patents

Abstract

PURPOSE: To shield an inverter from its controller even is an insulating case is used and to obtain a predetermined ground point. CONSTITUTION: The interior of an insulating case 44 is divided into upper and lower regions 56, 58 by an insulating chassis 50, and the high-frequency transformer 12 of a TIG arc welder, a high-frequency generator 28 and a radiation fin 64 are provided in the region 56. A semiconductor module 66 which loads an input side rectifier, an inverter and a semiconductor element for forming an output side rectifier in coupled to the fin 64, and disposed in the region 56. The printed board 82 of the controller of the inverter is disposed near the module 66 in the region 56. A conductor plate 88 is disposed between the board 82 and a module 86, and can be connected to a ground potential point. The plate 88 performs a shielding function and serves as a ground point which does not move.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device such as an arc welding machine, a plasma arc cutting machine, a charger, and a power supply device for precious metal plating.

[0002]

2. Description of the Related Art Conventionally, as a power supply device as described above,
A commercial AC power supply is rectified by a rectifier, the switching transistor supplied with this rectified output is switched at a high frequency, converted into high frequency power, then transformed using a high frequency transformer, and rectified by the rectifier again before being output. Is being used. Since such a power supply device does not require a large transformer or a large choke, there is an advantage that the entire device, particularly a main circuit including a switching transistor, a high frequency transformer and the like can be downsized.

In order to further reduce the weight of such power supply devices, the applicant of the present application has adopted a plastic case as the case of these power supply devices in Japanese Patent Application Laid-Open No. 5-283870 and Japanese Patent Application No. 6-300363. Proposing a power supply.

[0004]

However, as the size of such a power supply device is reduced, a switching circuit such as a switching transistor and a main circuit such as a high frequency transformer are closer to a control circuit for controlling the switching circuit. Will be done. Therefore, there is a problem that the control circuit is likely to malfunction due to the high-frequency signal generated by the switching operation of the switching circuit.

Further, since the case is made of plastic which is an insulator, the case cannot be used as a ground. Therefore, a ground wire is laid inside the case, but this ground wire moves every time inside the case. In addition, there is a problem in that the values of the parasitic capacitance and the parasitic inductance change, which causes the ground point to move, which makes it more susceptible to noise and causing malfunctions. Further, when such a power supply device is used as a power supply for a TIG arc welder, there is a gap between the welding work and the torch at the time of startup, and a high-voltage high-frequency signal is applied in order to perform discharge in this gap. To do. There is also a problem that this high-frequency signal causes noise to other devices and causes damage or malfunction of the other devices.

It is an object of the present invention to satisfactorily shield between a switching circuit and its control circuit even when an insulating case is used. Another object of the present invention is to ensure a constant ground point even when an insulating case is used. Another object of the present invention is to prevent leakage of a high frequency signal to the outside even when an insulating case is used.

[0007]

The first aspect of the present invention includes an insulating envelope, a main circuit which is provided in the envelope and includes switching means for switching DC power,
A control means provided in the envelope for controlling the switching means; and a shield means provided between the switching means and the control means and connectable to a ground potential point. To do. Further, in the second invention, in the first invention, the switching means and the control means are arranged close to each other. Further, in the third invention, in the first or second invention, the shield means is a plate-like body and is fixed inside the envelope.

In a fourth aspect of the present invention based on the third aspect, the main circuit has direct current converting means for converting the alternating current power generated by the switching means into direct current and supplying the alternating current power between two output terminals. One of the two output terminals is connectable to a base material that is grounded, the other output terminal is connectable to a torch, and the main circuit connects the torch and the base material from the other output terminal. A high frequency signal generating means for applying a high frequency signal is provided between the shield means and the high frequency signal generating means, and a bypass capacitor for the high frequency signal is provided between the shield means and the high frequency signal generating means. A fifth aspect of the present invention is the same as the fourth aspect, wherein a bypass capacitor is provided between the one output terminal and the shield means.

In a sixth aspect of the present invention, the control means for controlling the operation of the high-frequency signal generating means according to the fourth or fifth aspect of the invention, and the energizing signal is supplied to the control means via a pair of transmission lines. And a capacitor provided between the pair of transmission lines and the shield means.

In a seventh invention according to the fourth or fifth invention, control means for controlling the operation of the high-frequency signal generating means, and an energizing signal are supplied to the control means via a pair of transmission lines. Urging signal generating means, high frequency signal blocking means respectively interposed in the pair of transmission lines, and a capacitor provided between one end of the high frequency signal blocking means and the shield means. It is an electric charge. The 8th invention of the present invention, in the 7th invention, comprises a capacitor provided between the other end of said high-frequency signal blocking means and said shield means.

A ninth aspect of the present invention is to provide an insulating envelope, a first output terminal provided on the envelope and connectable to a base material, and provided on the envelope with a torch. A second output terminal connectable to the second output terminal, a DC power supply means provided in the envelope for supplying DC power to the first and second output terminals via a pair of transmission lines, and the transmission. High frequency signal generating means interposed on the torch side of the path, reference potential means connectable to a ground potential point and fixed in the envelope, the high frequency generating means and the reference potential means And a bypass capacitor provided between the two.

The tenth invention is the ninth invention, wherein
Control means of the high-frequency signal generating means, switch means connected to the control means via a pair of transmission lines so as to operate the control means, one end of each of the transmission lines and the other end thereof. Low pass filter means including a capacitor connected to the reference potential means.

In the eleventh aspect of the invention, in the ninth or tenth aspect of the invention, the DC power supply means is provided close to the AC conversion means for converting the DC power into AC power by switching. And a control means for the alternating current means, wherein the reference potential means is the alternating current means,
It is a plate-shaped body provided between the control means of this alternating current means.

[0014]

According to the first and second inventions, the shield means connectable to the ground potential point is provided between the switching means in the insulating envelope and the control means for controlling the switching means. Therefore, by connecting the shield means to the ground potential point, the high frequency signal generated by the switching means does not reach the control means side. Further, according to the third aspect of the invention, since the shield means is a plate-shaped body and is fixed, it can be used as a ground and the ground point does not move.

According to the fourth aspect of the invention, the main circuit has the direct current converting means and the high frequency signal generating means, and the high frequency signal generating means discharges between the torch and the base material. The generated high frequency signal flows from the base material to the reference potential point. Further, the high frequency signal leaked from the high frequency signal generating means is bypassed to the shield means which is an immovable earth point through the bypass capacitor. In the fifth aspect of the invention, in addition to this bypass, even if a public signal from another device is induced to one output terminal side, it is bypassed to the shield means via another bypass capacitor.

According to the sixth aspect of the present invention, the control means for controlling the operation of the high frequency signal generating means operates the high frequency signal generating means in response to the signal from the biasing signal generating means. Even if a high-frequency signal from another device is superposed on the pair of transmission lines between the control means and the control means, it is bypassed to the shield means by the capacitor between the transmission path and the shield means.

According to the seventh invention, like the sixth invention, a high-frequency signal from another device is bypassed by a capacitor, but further, since a high-frequency signal blocking means is provided in the transmission line, It is possible to more firmly prevent the high-frequency signal from the device from reaching the control means.
According to the eighth aspect of the invention, since the capacitors connected to the shield means are provided at both ends of the high frequency blocking means, the high frequency blocking means and the two capacitors cooperate to control the high frequency signal more firmly. It can prevent you from reaching the means.

According to the ninth aspect of the invention, the insulating envelope is provided with DC power supply means for supplying DC power between the torch and the base material, and further, the torch and the base material are initially provided. A high frequency signal generating means for initiating a discharge is also provided in the insulating envelope. The high frequency signal generated by the high frequency signal generating means flows from the torch and the base material to the ground potential point. Also, if the reference potential means is connected to the ground potential point, the reference potential means is fixed inside the envelope, so that the ground point can be moved without changing the parasitic capacitance or the parasitic inductance. There is no. The high frequency signal is bypassed to the reference potential point by the capacitor provided between the reference potential point and the high frequency signal generating means.

According to the tenth aspect of the present invention, the switch means is connected to the control means via the pair of transmission lines so as to operate the control means of the high frequency signal generation means. There is a possibility that the high frequency signal of is superposed. However, since low-pass filter means including a capacitor, one end of which is connected to the transmission path and the other end of which is connected to the reference potential means, is provided, it is possible to prevent such a high-frequency signal from reaching the control means. You can

According to the eleventh aspect of the present invention, the DC power supply means includes an AC conversion means for converting DC power into AC power by switching, and a control means for the AC conversion means provided close to the AC conversion means. Since the reference potential means is a plate-shaped body provided between the alternating current means and the control means of the alternating current means, the arrival of the high frequency signal as described above or the outside. Not only can the radiation of the high frequency signal be blocked, but the reference potential means also serves as a shield function, so the high frequency signal radiated from the alternating current means arrives at the control means of the alternating current means and causes it to malfunction. There is no such thing.

[0021]

In this embodiment, the present invention is applied to, for example, a DC power supply device of a DC TIG welding machine and has input terminals 2 and 4 of a commercial AC power supply as shown in FIG. The commercial AC power supplied to these input terminals 2 and 4 is rectified by the input side rectifier circuit 6 and then smoothed by the smoothing capacitor 8 to be converted into DC.

The DC-converted electric power is converted into high-frequency AC electric power by the inverter 10 composed of switching means, for example, an electric power switching transistor such as an IGBT. This AC power is supplied to the primary side of the high frequency transformer 12, and a predetermined voltage is generated on the secondary side thereof.

The high frequency voltage generated on the secondary side of the high frequency transformer 12 is rectified by the output side rectifying circuit 14,
It is made DC again. The re-DC power is supplied to the positive and negative output terminals 16 and 18 via the transmission lines 19 and 21.

These input side rectification circuit 6 and inverter 1
0, the high frequency transformer 14 and the like constitute the main circuit. By increasing the output frequency of the inverter 10, the high frequency transformer 14 can be downsized, and the power supply device can also be downsized.

The positive output terminal 16 is connected to a base material, for example, a welding work 20 via a cable 22, and the work 20 is connected to a ground potential point. The negative output terminal 18 is connected to the torch 24 via a cable 26.

Although not shown, an inert gas is supplied to the torch 24 so that the inert gas can be injected from the torch 24 toward the work 20 for TIG welding.

Further, since there is a gap between the torch 24 and the work piece 20, at the start of welding, in order to generate an electric discharge, that is, an arc, between the torch 24 and the work piece 20, a high gap is formed between the torch 24 and the work piece 20. It is necessary to apply a high frequency signal of voltage. Therefore, the transmission path 21 between the negative output terminal 18 and the output side rectification circuit 14 is provided with high frequency signal generation means, for example, a high frequency generation device 28. The high frequency generator 28 starts its operation in response to the activation signal from the sequence circuit 30. Although not shown, the sequence circuit 30 also supplies and stops the inert gas by controlling the opening and closing of a valve 76 described later.

Further, in order to perform constant current control of the load current while welding is being performed, a portion of the transmission line 21 which is closer to the output side rectifier circuit 14 than the high frequency generator 28 is formed by, for example, a current transformer. A current detector 31 is provided. The current detector 31 detects the load current, and this detection signal is fed back to the control device 32 that drives and controls the inverter 10. by this,
The controller 32 controls the inverter 10 to make the load current a constant current. The control device 32 also controls the sequence circuit 30.

That is, the controller 32 is connected to the torch switch connection terminals 34 and 36 via the transmission lines 35 and 37, and these torch switch connection terminals 34 and 36 are connected to each other.
The torch switch 38 provided on the torch 24 is connected via cables 40 and 42. These cables 40 and 42 are laid in parallel with the cables 22 and 26 connected to the positive and negative output terminals 16 and 18, respectively.

When the torch switch 38 is closed, an energizing signal is supplied to the control device 32, the control device 32 operates the sequence circuit 30, and the sequence circuit 30 starts the supply of the inert gas, and thereafter. The high frequency generator 28 is activated. In this way, the control device 32 and the sequence circuit 30 function as control means for the high frequency generator 28, and the torch switch 38 functions as energizing signal generating means. When the arc is generated, the sequence circuit 30 stops the high frequency generator 28.

Such a power supply unit is housed in an envelope, for example, a case 44, as shown in FIG. The case 44 is made of an insulating material such as a synthetic resin front panel 4
Have six. A rear panel 48 is arranged at a distance from the front panel 46 in the left-right direction shown in FIG. The rear panel 48 is also made of synthetic resin. Also,
A chassis 50 made of synthetic resin is attached to the front panel 46 and the rear panel 48 at substantially the center in the vertical direction.

The chassis 50 has a substantially rectangular planar shape, and engaging claws 52 are provided at four corners of the chassis 50. The engaging claws 52 are engaged with the front panel 46 and the rear panel 48, respectively. are doing. Front panel 46,
Since the rear panel 48 and the chassis 50 are formed in a substantially H shape, compression received from all directions,
It has a structure that does not easily deform when pulled or bent.

Further, the front panel 46 and the rear panel 48
Two side plates 54 having the same shape are provided so as to cover the upper portion, the lower portion, and both side portions of the.

Due to the chassis 50, the inside of the case 44 is
It is divided into two upper and lower regions 56 and 58. The high frequency transformer 12 is attached to the lower surface of the chassis 50 at a position near the front panel 46 in the lower region 58.

A recess 60 is provided at a position closer to the rear panel 48 side than the mounting position of the high frequency transformer 12 in the chassis 50, and a through hole 62 is formed in the bottom surface of the recess 60. Radiating fins 64 are attached to the lower surface of the chassis 50 corresponding to the through holes 62. Then, the power semiconductor module 66 is mounted on the heat radiation fin 64 so as to be located in the upper region 56 through the through hole 62. The semiconductor module 66 is formed in a substantially rectangular parallelepiped shape, and each semiconductor element that constitutes the inverter 10, the input side rectification circuit 6 and the output side rectification circuit 14, and the drive circuit of the inverter 10 in the control device 30 is mounted. Has been done.

A high-frequency generator 28 is arranged below the heat radiation fins 64.
It is supported by a mounting portion 67 provided on the No. 4. In this way, in the lower region 58 of the chassis 50, most of the main circuits such as the high frequency transformer 12, the high frequency generator 28, the heat radiation fins 64, etc. are housed.

On the lower surface side of the chassis 50 closest to the rear panel 48, the high frequency transformer 12 and the radiation fins 6 are provided.
4. A fan 68 for cooling the high frequency generator 28 is attached. The fan 68 is configured to discharge the air in the area 58 to the rear panel 48 side. A large number of exhaust holes 70 are formed in a region of the rear panel 48 below the chassis 50, and the air sent by the fan 68 via these is discharged to the outside of the case 44. Similarly, a large number of air supply holes 72 are formed in a region of the front panel 46 below the chassis 50, and are fed into a new region 58 from these.

Although the semiconductor module 56 itself is on the region 56 side, the heat radiation fins 64 to which the semiconductor module 66 is coupled are in the lower region 64, so that the heat generated by the semiconductor module 66 is transmitted to the heat radiation fin 64 side. Heat is radiated from this and is hardly transmitted to the upper region 56.

Below the exhaust hole 70 of the rear panel 48, a gas inflow portion 7 for introducing an inert gas from the outside is provided.
4 is provided through a valve 76 and a pipe 78 whose opening and closing are controlled by the sequence circuit 30.
It is coupled to a gas outflow portion 80 provided on the front panel 46. The gas outflow portion 80 is arranged below the air supply hole 72, and is further connected to the torch 24 via a hose (not shown). This inert gas is jetted from the torch 24. Although not shown, positive and negative output terminals 18 and 18, and torch connection terminals 34 and 36 are also provided on the front panel 46 in addition to this.

In the upper area 56 of the case 44, a printed circuit board 82, which constitutes the control device 32, the sequence circuit 30, etc., is arranged substantially horizontally. This printed circuit board 8
2 is a support body 82, 8 protruding from the upper surface of the chassis 50.
Supported by 4. In addition, this printed circuit board 8
The terminal 86 of the semiconductor module 66 is connected to the terminal 2. These terminals 86 are provided on one edge side of the semiconductor module 66 along a straight line connecting the front panel 46 and the rear panel 38.

As is apparent from FIG. 1, the semiconductor module 66 and the printed circuit board 82 are arranged in close proximity to each other, and the high frequency signal generated in the semiconductor module 66 is arranged on the printed circuit board 82 side. May be leaked to.

In order to prevent this, the printed circuit board 82
Between the semiconductor module 66 and the semiconductor module 66, a rectangular conductor plate 88 is arranged so as to substantially cover the upper surface of the semiconductor module 66 and not to contact the terminals 86. This conductor plate 88
Is made of, for example, copper or iron, and is attached to the printed circuit board 82 by the support 90. Further, as shown in FIG. 2, the conductor plate 88 can be connected to a ground potential point via a ground terminal 92. Although not shown, the ground terminal 92 is provided on the rear panel 48, for example. Of course, the conductor plate 88 and the ground terminal 93 are connected at the shortest distance.

By connecting the ground terminal 92 to the ground potential point, the conductor plate 88 also becomes the ground potential, and exhibits a shielding effect for preventing the high-frequency signal from the semiconductor module 66 from leaking to the printed circuit board 82 side. That is, the conductor plate 88 functions as a shield means.

The conductor plate 88 has a larger area than that of a conductor generally used as an earth line and the like, and the ground terminal 9
It is connected to the ground potential point via 2 and is attached to the printed circuit board 82, so that it does not move.
Therefore, for example, as compared with the case where a conducting wire serving as an earth line connected to the ground terminal 88 is routed inside the insulating case 44, the values of the parasitic capacitance and the parasitic inductance are small, and their changes are small, and the movement of the earth point is reduced. There is no. That is, the ground point is fixed.

As shown in FIG. 2, a bypass capacitor 94, one end of which is connected between the current detector 31 and the high frequency generator 28, and one end of which is connected to the transmission line 19 are connected to the conductor plate 68. The interconnection point with the bypass capacitor 96 is connected. That is, a bypass path is formed by the capacitor 94 between the connection point between the current detector 31 and the high frequency generator 28 and the conductor plate 88, and the transmission path 1
A bypass path is formed between the capacitor 9 and the conductor plate 88 by the capacitor 96.

A high-frequency signal from the high-frequency generator 28 has a negative output terminal 18, a cable 26, a torch 24, and a work 2.
The high-frequency signal, which flows through 0 to the ground potential point but leaks from the high-frequency generator 28 at the same time, is bypassed via the capacitor 94 to the conductor plate 88, which is an immobile ground point. Therefore, the high frequency signal from the high frequency generator 28 does not interfere with other devices.

Further, since the capacitor 96 is provided between the transmission line 19 and the conductor plate 88, when a plurality of TIG welding machines using such a power supply device are used at the same time,
Even if a high frequency signal from another welding machine is superimposed on the transmission line 19 via the cable 22 and the positive output terminal 16, this high frequency signal can be bypassed to the conductor plate 88 via the capacitor 96.

Further, high frequency blocking means, for example, reactors 98 and 100 are provided in the transmission lines 35 and 37 between the control device 32 and the torch switch connection terminals 34 and 36, and one end of these is connected to one end. The interconnection point of the connected bypass capacitors 102 and 104 is connected to the conductor plate 88.

Similarly, the bypass capacitors 106 and 10 each having one end connected to the other end of the reactors 98 and 100.
Eight interconnection points are connected to the conductor plate 88. The reactor 98 and the capacitors 102 and 106 form a low-pass filter.
0 and the capacitors 104 and 108 form a low-pass filter.

As described above, the cables 22 and 24 for supplying the load current to the torch 24 and the cables 40 and 42 connected to the torch switch 38 are wired in parallel. Further, as described above, a plurality of such welding machines may be used at the same time. In such a case, a high-frequency signal from its own high-frequency generator 28 or a high-frequency signal from the high-frequency generator 28 of another welding machine may be superimposed on the cable 40 or 42. Cables 40 and 4
Which of the two superimposes the high-frequency signal differs from time to time. By bypassing the high frequency signal superimposed on any of the cables to the conductor plate 88, the transmission line 3
The capacitors 106,
108 is provided. The capacitors 94 and 96
It is desirable to connect the interconnection point of 1), the interconnection point of capacitors 102 and 104, and the interconnection point of capacitors 106 and 108 to the same place on the conductor plate 88. By doing so, a single-point ground is provided, and the ground impedance can be made smaller than in the case where the connection points are dispersed, and the high frequency signal can be bypassed favorably.

In the above embodiment, the capacitor 96 is provided to bypass the high frequency signal superimposed on the transmission line 19, but it is not necessary in some cases. Similarly, although the capacitors 102 and 104 and the capacitors 106 and 108 are provided, the capacitors 102 and 104 may be removed or the transmission lines 35 and 37 may be removed when a high frequency signal is difficult to be superimposed on the cables 40 and 42. When it is difficult to superimpose a high frequency signal on the capacitor, the capacitors 106 and 108 may be removed. Further, in order to configure a low pass filter, the reactor 9
Although 8, 100 are provided, they may be removed depending on the case.

In the above embodiment, the present invention is applied to the power supply device for the TIG welding machine. However, the present invention is not limited to this. For example, a power supply for arc equipment including a plasma arc cutting machine, a charger, The present invention can be applied to a power supply device for precious metal plating. For example, the configuration of the above embodiment can be used as it is as a charger or the like. However, when it is used as a dedicated device such as a charger, the high frequency generator 28 and devices related thereto need to be provided. Absent.

[0053]

According to the first aspect of the invention, the shield means, which is connectable to the ground potential point, is provided between the switching means and the control means even though the insulating envelope is used. Since the shield means is connected to the ground potential point, it is possible to prevent the high-frequency signal generated by the switching means from leaking to the control means side and prevent the control means from malfunctioning. According to the second aspect of the invention, since the control means and the switching means are close to each other, leakage of high frequency signals is likely to occur, but since the shield means is provided, it is possible to reliably prevent malfunction. You can

According to the third aspect of the invention, since the shield means is a plate-like member, the area is larger than that of the ground wire or the like, so that the occurrence of parasitic inductance and the like is small and the shield is fixed. The shield means itself does not move, and the parasitic inductance and the like hardly change. Therefore, a fixed ground point can be secured.

According to the fourth aspect of the present invention, when a high frequency signal is applied between the torch and the base material by the high frequency signal generating means, the high frequency signal may leak from the high frequency signal generating means. Since the leakage high-frequency signal is bypassed by the bypass capacitor to the shield means which is an immovable earth point, it is possible to prevent the control means and the switching means from malfunctioning or being damaged. According to the invention described in claim 5, even if a leakage high frequency signal is induced from the outside to the other output terminal, it is bypassed by the bypass capacitor provided between the other output terminal and the shield means. It is possible to prevent the or switching means from malfunctioning or being damaged.

According to the sixth aspect of the present invention, even if the high frequency signal is superposed on the transmission line for supplying the bias signal from the bias signal generation means to the control means for controlling the operation start of the high frequency signal generation means. By being bypassed by the capacitor provided between the transmission line and the shield means, it is possible to prevent the control means and the switching means from malfunctioning or being damaged. Further, according to the invention of claim 7, since the above-mentioned capacitor and the high frequency blocking means constitute a low-pass filter, the control means and the switching means are more reliably prevented from malfunctioning or being damaged. can do. According to the invention described in claim 8, since the high frequency signal blocking means is further loaded with the capacitor, it is possible to more reliably prevent the control means and the switching means from malfunctioning or being damaged.

According to the ninth aspect of the present invention, the reference potential means connectable to the reference potential point is provided in the insulating envelope even though the insulating envelope is used. Since it is limited, since a bypass capacitor is provided between the reference potential point that does not move and the high frequency signal blocking means, it is possible to reliably bypass the high frequency signal leaked from the high frequency signal generating means. , Does not interfere with other equipment.

According to the tenth aspect of the invention, the capacitors of the low-pass filters provided in the pair of transmission lines between the switch means and the control means of the high-frequency signal generating means can be moved as described above. Since it is connected to the non-reference potential means, even if a high frequency signal is superimposed on the transmission line, it can be bypassed. Therefore, the control means of the high frequency signal generating means does not malfunction.

According to the eleventh aspect of the present invention, the reference potential means is provided between the AC converting means included in the DC converting means and the control means of the AC converting means arranged close to the AC converting means. Since the reference potential means also functions as a shield means, it is possible to prevent the high-frequency signal generated by the AC converting means from leaking to the control means, and prevent malfunction or damage of the control means. .

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an embodiment of a power supply device according to the present invention.

FIG. 2 is a block diagram of the embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Inverter (switching means) 14 Output side rectifier circuit (DC conversion means) 16 Positive output terminal 18 Negative output terminal 20 Work (base material) 24 Torch 26 High frequency generator (high frequency signal generating means) 30 Sequence circuit (high frequency signal) Control means for generating means) 32 Control device (control means) 35 37 Transmission line 40 Torch switch (energizing signal generating means) 88 Conductor plate (shielding means, reference potential means) 94 Bypass capacitor 96 Bypass capacitor 98 100 Reactor ( High-frequency signal blocking means) 102 104 106 108 Bypass capacitor

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Atsushi Kinoshita 2-14-3 Awaji, Higashiyodogawa-ku, Osaka City, Osaka Prefecture Sansha Electric Manufacturing Co., Ltd. (72) Takashi Hashimoto 2-chome, Awaji, Higashiyodogawa-ku, Osaka City, Osaka Prefecture No.14-3 Sansha Electric Manufacturing Co., Ltd.

Claims (11)

[Claims] 1. An insulative envelope, a main circuit provided in the envelope, including a switching means for switching DC power, and provided in the envelope.
A power supply device comprising: control means for controlling the switching means; and shield means provided between the switching means and the control means and connectable to a ground potential point. 2. The power supply device according to claim 1, wherein the switching means and the control means are arranged close to each other. 3. The power supply device according to claim 1, wherein the shield means is a plate-like body and is fixed inside the envelope. 4. The power supply device according to claim 3, wherein the main circuit has direct current converting means for converting the alternating current power generated by the switching means into direct current and supplying the direct current between two output terminals. One of the output terminals is connectable to a base material that is grounded, the other output terminal is connectable to a torch, and the main circuit is arranged between the other output terminal and the torch and the base material. A power supply device having a high-frequency signal generating means for applying a high-frequency signal, wherein a bypass capacitor is provided between the shield means and the high-frequency signal generating means. 5. The power supply device according to claim 4, wherein a bypass capacitor is provided between the one output terminal and the shield means. 6. The power supply device according to claim 4 or 5, wherein control means for controlling the start and stop of operation of the high-frequency signal generation means, and an energizing signal are supplied to the control means via a pair of transmission lines. A power supply device comprising: an energizing signal generating means, and a capacitor respectively provided between the pair of transmission lines and the shield means. 7. The power supply device according to claim 4, wherein the control means for controlling the operation of the high-frequency signal generation means, and an energizing signal for supplying an energizing signal to the control means via a pair of transmission paths. A power supply device including signal generation means, high frequency signal blocking means respectively interposed in the pair of transmission lines, and a capacitor provided between one end of the high frequency signal blocking means and the shield means. . 8. The power supply device according to claim 7, further comprising a capacitor provided between the other end of the high frequency signal blocking means and the shield means. 9. An insulating envelope, a first output terminal provided on the envelope and connectable to a base material, and a first output terminal provided on the envelope and connectable to a torch. Two output terminals, DC power supply means provided in the envelope for supplying DC power to the first and second output terminals via a pair of transmission lines, and one of the transmission lines on the torch side. The high-frequency signal generating means interposed in the object, the reference potential means connectable to the ground potential point and fixed in the envelope, and provided between the high-frequency generating means and the reference potential means. A power supply device comprising a bypass capacitor. 10. The power supply device according to claim 9, further comprising: a control means for the high-frequency signal generation means, and a switch means connected to the control means via a pair of transmission lines for operating the control means. A low-pass filter means including a capacitor having one end connected to each of the transmission lines and the other end connected to the reference potential means. 11. The power supply device according to claim 9, wherein the DC power supply means converts the DC power into AC power by switching, and an AC conversion means provided close to the AC conversion means. Means for controlling the means,
A power supply device, comprising: the reference potential means, which is a plate-shaped body provided between the alternating current means and the control means of the alternating current means.