JP2001105132A - Power supply for gouging, power supply for welding, power supply for cutting and control method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control method, a power supply for gouging, a power supply for welding and power supply for cutting, with which an energy saving is realized when the work is not executed and a damage to a work is prevented. SOLUTION: The device is provided with a switch which opens and closes an input current, an air sensor which detects an air flow rate or a air pressure, a discriminating device which detects whether the air flow rate or the air pressure is at more or less than a predetermined value, a switch control circuit, to which the output of the discriminating device is input, which outputs a signal to the switch which is closed when the air flow rate or the air pressure reaches the predetermined value or greater and opened when a predetermined time has elapsed after the air flow rate or the air pressure reaches the predetermined value or less. Thus the input to a power supply for gouging is cut when the gouging is not executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a power source for a gouging, in which an arc is generated between a gouging rod and a base material (work), and the work is detached (blown) using air. .

An arc is generated between a consumable electrode (hereinafter referred to as a welding wire) and a base material (work), and a welding power source for performing welding using a working gas (shielding gas) and an electrode and base material ( The present invention relates to a method for controlling a cutting power supply that generates an arc between the cutting power supply and a workpiece and performs cutting using a working gas (air, oxygen, or the like).

[0003]

2. Description of the Related Art A conventional gouging power supply does not use a means for detecting the flow rate or pressure of air, so that a no-load voltage is always output while a power switch is turned on, and the fan rotates.

Next, the structure of a conventional gouging power supply will be described with reference to FIG. In FIG. 3, 5 is air, 6 is
Is an input power supply, 7 is a switch, 8 is a main transformer, 9 is a fan, 10 is a switching element, 1 is a switching control circuit unit, 4 is an output setter, 11 is a current detector, 12 is a reactor, and 13 is an interphase reactor. , 15 is air ON / OFF
A switch, 16 is a gouging torch, 17 is a gouging rod, and 18 is a work (base material).

Next, the operation of the power supply for gouging when the gouging work is not performed will be described below. Although not shown, when the switch of the gouging power supply is ON, the switch 7 is always closed and the current flows to the main transformer 8, the switching element 10 is always turned on, the no-load voltage is output, and the fan 9 always rotates.

Further, in a conventional welding power source, when a torch switch disposed on a torch is turned on, a no-load voltage is output using this signal as a start signal. Further, when the output current flows, the fan rotates, and the rotation of the fan stops after a predetermined time has elapsed from when the output current stopped.

Next, the configuration of a conventional welding power supply will be described with reference to FIG. 4, reference numeral 2 denotes a switch control circuit unit,
3 is a fan control circuit unit, 20 is a start signal output unit, 21 is a torch switch, 22 is a welding torch, 23 is a welding wire, 24 is a gas valve, 25 is a wire feeder, 26
Is a working gas.

The same components as those described with reference to FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted.

Next, the operation of the welding power supply will be described below. When the torch switch 21 is turned on, the start signal output unit 20 outputs a signal to the switch 7, the switching element 10, and the gas valve 24 to operate. afterwards,
The current detector 11 detects that the output current flows, and the fan 9
Are rotated, and the rotation of the fan 9 is stopped after a lapse of a predetermined time from when the output current is stopped.

Although not shown, the configuration of the power supply for cutting is different from the configuration of the power supply for welding because there is no welding wire. Therefore, only the torch switch 21 is disposed on the welding torch 22, and the gas valve 24 is provided in the power supply for cutting. Located, no wire feeder.

The operation of the cutting power supply is the same as the operation of the welding power supply.

[0012]

In the prior art, when no gouging is performed, a current flows through the main transformer, a no-load voltage is output, and the fan rotates. Power was wasted.

Further, since a no-load voltage is constantly applied to the gouging rod and the work, the work may be damaged when they come into contact with each other.

The present invention provides an energy-saving gouging power supply that shuts off input to the gouging power supply, stops output of the gouging power supply, and stops a fan when gouging is not performed. An object of the present invention is to provide a gouging power supply for preventing a work from being damaged even when a work bar comes into contact with the work.

Further, in the conventional apparatus, energy saving is performed when the contact work or the cutting work is not performed, but when the work is performed, the work is performed even if an appropriate working gas is not flowing.

In this case, an appropriate strength and bead or cutting result could not be obtained, and it was necessary to check the flow rate or pressure of the working gas before performing the work again.

[0017] If it cannot be reworked, all of the construction members must be discarded. Therefore, the present invention detects that the flow rate or the pressure of the working gas is equal to or more than an appropriate value, and uses the detection signal as a construction start signal. The present invention also provides an energy-saving power supply for welding and a power supply for cutting capable of performing the above-mentioned operations.

[0018]

In order to achieve the above object, the present invention relates to a switch for opening and closing an input when an air flow rate or a pressure exceeds a predetermined value, and an input voltage is input to a gouging power supply. The switch is controlled so that the switch is opened and the input of the input voltage to the gouging power supply is cut off after a lapse of a predetermined time after the flow rate or pressure of the air becomes equal to or less than a predetermined value.

When the flow rate or the pressure of the air exceeds a predetermined value, the switching element for adjusting the output is turned on and output, and after a predetermined time has passed since the flow rate or the pressure of the air has become a predetermined value or less, the switching element is turned off. The output is controlled to be turned off and the output is stopped.

When the flow rate or pressure of the air exceeds a predetermined value, the fan rotates, and when the flow rate or the pressure of the air drops below the predetermined value or when the output current is stopped, a predetermined time period elapses from the start of time. This controls the fan to stop the fan.

Further, according to the present invention, when the flow rate or pressure of the working gas becomes equal to or more than a predetermined value, the switch for opening and closing the input is closed and the input voltage is input to the welding power source or the cutting power source, and the flow rate or pressure of the working gas is reduced. The switch is controlled so that the switch is opened and the input of the input voltage to the welding power source or the cutting power source is cut off after a lapse of a predetermined time from the time when the voltage becomes equal to or less than a predetermined value.

When the flow rate or pressure of the working gas exceeds a predetermined value, a switching element for adjusting the output is turned on and output, and after a predetermined time elapses after the flow rate or the pressure of the working gas falls below a predetermined value, the switching is performed. Element is off
Then, output control for stopping the output is performed.

Further, when the flow rate or pressure of the working gas exceeds a predetermined value, the fan rotates, and when the flow rate or the pressure of the working gas falls below the predetermined value or when the output current is stopped, a predetermined time elapses. The fan is controlled to stop the fan in any of the above.

[0024]

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a configuration of a gouging power supply according to an embodiment of the present invention.

1 is a switching control circuit, 2 is a switch control circuit, 3 is a fan control circuit, 4 is an output setter,
5 is air, 6 is an input power source, 7 is a switch, 8 is a main transformer, 9 is a fan, 10 is a switching element, 11 is a current detector, 12 is a reactor, 13 is an interphase reactor, 14 is an air sensor, and 15 is Air ON / OFF switch,
16 is a gouging torch, 17 is a gouging rod, 18
Is a work, and 19 is a discriminator.

A switch 7 is provided between the input power supply 6 and the primary side of the main transformer 8.

A switching element 10 is provided on the secondary side of the main transformer 8 to adjust the output. The switching element 10 is controlled by the switching control circuit unit 1 in accordance with the contents set by the output setting unit 4.

A current detector 11 is provided on the secondary side of the main transformer 8.
, And an inter-phase reactor 13 via the switching element 10.

The output of the reactor 12 is connected to a gouging rod 17 via a gouging torch 16 and the output of the interphase reactor 13 is connected to a work 18 so as to supply controlled power.

The air 5 is supplied to the gouging torch 16 through the air sensor 14.
The output from the gouging torch 16 is controlled by the air ON / OFF switch 15.

The output of the air sensor 14 is input to a discriminator 19, and the output of the discriminator 19 is input to a switching control circuit 1, a switch control circuit 2, and a fan control circuit 3.

The output of the current detector 11 is also input to the fan control circuit 3, and the output of the fan control circuit 3 is connected to the fan 9.

That is, a switch 7 for opening and closing an input, an air sensor 14 for detecting a flow rate or pressure of air,
A discriminator 19 which receives the output of the air sensor 14 as an input and detects whether the flow rate or the pressure of the air is above or below a predetermined value
The switch 7 is closed when the flow rate or pressure of the air becomes equal to or more than a predetermined value by using the output of the discriminator 19 as an input, and after a predetermined time elapses after the flow rate or pressure of air becomes equal to or less than the predetermined value, the switch 7 is closed. A switch control circuit 2 for outputting a signal to open the switch to the switch is provided so that the input to the gouging power supply is cut off when gouging is not performed.

Thus, the no-load loss of the main transformer 8 is eliminated, and energy is saved.

Further, since the output of the gouging power supply is stopped, the work 18 can be prevented from being damaged even if the gouging rod 17 and the work 18 come into contact with each other.

When the flow rate or the pressure of the air becomes equal to or less than the predetermined value when the switch 7 is opened, the predetermined time elapses when performing gouging work continuously, that is, when the gouging rod 1 is used.
This is to prevent the input from being interrupted when the workpiece 7 and the workpiece 18 are in contact with each other.
May be.

Next, the switching element 1 for adjusting the output
0, an output setting device 4 for setting an output, and a switching element 1 according to the output of the output setting device 4 when the flow rate or pressure of the air becomes equal to or more than a predetermined value with the output of the discriminator 19 as an input.
0 is turned on, and the switching element 14 is turned off after a lapse of a predetermined time since the flow rate or pressure of the air becomes a predetermined value or less.
A switching control circuit 2 for outputting a signal to the switching element 14 is provided to stop the output of the power supply for gouging when gouging is not performed.

Thus, the output of the gouging power supply is stopped, so that even if the gouging rod 17 and the work 18 come into contact with each other, the work 18 can be prevented from being damaged.

When the switching element 14 is turned off, the predetermined time elapses from the time when the flow rate or pressure of the air becomes equal to or less than the predetermined value, when performing gouging work continuously, that is, when the gouging rod 17 and the work 18 come into contact with each other. This is to prevent the output from being stopped when the power is on, and the predetermined time may be 0 depending on the construction situation.

A fan 9 for cooling the inside of the power supply, a current detector 11 for detecting an output current,
With the output of 1 and the output of the discriminator 19 as inputs, the fan 9 rotates when the air flow rate is equal to or more than a predetermined value, and when the flow rate or pressure of air becomes equal to or less than a predetermined value or when the output current is stopped, A fan control circuit unit 3 that outputs a signal for stopping the fan 9 to the fan 9 at one of the predetermined time intervals is provided, and the fan 9 is stopped when gouging is not performed.

As a result, the power consumption of the fan 9 is eliminated to save energy.

The reason why the predetermined period of time is used when the output current stops when the fan 9 is stopped is to sufficiently cool the heat-generating components inside the power supply due to the flow of the output current.

The provision of the discriminator 19 has the advantage that the discrimination value can be adjusted. However, if the discrimination value may be fixed, the discrimination value of the flow rate switch or the pressure switch is fixed. A certain part may be used as an alternative to the air sensor 14 and the discriminator 19.

When the flow rate or the pressure of the working gas exceeds a predetermined value, the supply of electric power from the welding power source or the cutting power source is started, and after a predetermined time period has elapsed since the flow rate or the pressure of the working gas became lower than the predetermined value. Thereafter, the supply of power from the welding power source or the cutting power source is stopped.

Further, when the flow rate or pressure of the working gas exceeds a predetermined value, a switch for opening and closing the input is closed, and the input voltage is input to the welding power source or the cutting power source, and the flow rate or the pressure of the working gas is lower than the predetermined value. After a predetermined time elapses, the switch is opened and the input of the input voltage to the welding power source or the cutting power source is cut off.

Next, another embodiment of the present invention will be described with reference to FIG.

The same components as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

A switch 7 for opening and closing an input, an air sensor 14 for detecting the flow rate or pressure of the working gas, and an output of the air sensor 14 is used as an input to detect whether the flow rate or pressure of air is above or below a predetermined value. A discriminator 19, a switch control circuit 2 for controlling the opening and closing of the switch 7 by using an output of the discriminator 19 as an input, a torch switch 21 disposed on a torch 22, and a wire feeder 25. A gas valve 24, a torch switch 21 is turned on, and a start signal output unit 20 that outputs a start signal in response to the ON signal, and a gas valve 24 that opens the valve by the start signal, and the torch switch 21 is turned on. And the start signal output unit 20 outputs a start signal to the gas valve 24.

When the gas valve 24 is opened, the working gas 26
Then, the air sensor 14 detects the flow rate or pressure of the working gas and outputs it to the discriminator 19. The discriminator 1
9 detects whether the flow rate or the pressure of the working gas is equal to or more than a predetermined value, and the switch control circuit unit 2 closes the switch 7 when the flow rate or the pressure of the working gas becomes equal to or more than the predetermined value. Alternatively, a signal for opening the switch 7 is output to the switch 7 after a lapse of a predetermined time after the pressure has become equal to or lower than the predetermined value, and the welding power source of the input voltage or the welding voltage of the input voltage only when the working gas having an appropriate flow rate or pressure is flowing. Allow input to the power supply for disconnection.

As a result, the current flowing through the main transformer 8 when the working gas having the appropriate flow rate or pressure is not flowing is eliminated, and energy is saved. The reason why the predetermined time elapses from the time when the flow rate or the pressure of the working gas becomes equal to or less than the predetermined value when the switch 7 is opened is when welding or cutting is performed continuously in the operation of the switch 7, that is, for welding. This is to prevent the input from being interrupted when the work 18 is in contact with the wire 23 or the electrode, and the predetermined time may be 0 depending on the construction situation.

The switching element 1 for adjusting the output
0, an output setting device 4 for setting an output, and the discriminator 19
When the flow rate or pressure of the working gas becomes equal to or more than a predetermined value, the switching element 10 is turned on, and the output of the welding power source or the cutting power source is adjusted in accordance with the output of the output setting device 4. A switching control circuit section 1 for outputting a signal for turning off the switching element 10 to the switching element 10 after a predetermined time has elapsed after the flow rate or pressure of the working gas has become equal to or less than a predetermined value. Only when the power is on, the output of welding power or cutting power is permitted.

This eliminates the no-load loss when the working gas of the appropriate flow rate or pressure is not flowing, thereby saving energy.

When the switching element 10 is turned off, the predetermined time elapses from the time when the flow rate or the pressure of the working gas becomes equal to or less than the predetermined value, when performing welding or cutting continuously, that is, when the welding wire 23 or the welding wire 23 is used. This is to prevent the input from being interrupted when the electrode and the work 18 are in contact with each other, and the predetermined time may be 0 depending on the construction situation.

Further, a fan 9 for cooling the inside of the power supply,
An output current detector 11 for detecting an output current, and a fan 9 is rotated when an output of the output current detector 11 and an output of the discriminator 19 are input and a working gas flow rate becomes a predetermined value or more,
A fan control circuit unit 3 that outputs a signal to the fan 9 to stop the fan 9 at a time when a flow time or pressure of the working gas becomes equal to or less than a predetermined value or when the output current is stopped and a predetermined time elapses from a time start point. When the welding or cutting is not performed, the fan 9 is stopped.

As a result, the power consumption of the fan 9 is eliminated to save energy.

When the fan is stopped, the time period when the output current is stopped and the predetermined time has elapsed is used as the time starting point.
This is to sufficiently cool the heat-generating components inside the power supply due to the flow of the output current.

The provision of the discriminator 19 as described above has the advantage that the discrimination value can be adjusted.
When the discrimination value may be fixed, a component having a fixed discrimination value such as a flow switch or a pressure switch may be used as an alternative to the air sensor 14 and the discriminator 19.

[0059]

According to the gouging power supply and its control method of the present invention, when no gouging is performed, the no-load loss is eliminated by cutting off the input to the gouging power supply and stopping the output of the gouging power supply. I do.

Further, the fan is stopped to reduce the fan power consumption.

Thus, an energy saving effect is achieved when gouging is not performed.

Further, by stopping the output of the gouging power source, the work can be prevented from being damaged even if the gouging rod comes into contact with the work.

In the welding power source and the cutting power source and the control method thereof according to the present invention, while performing the welding operation or the cutting operation while saving the energy, while performing the operation, the flow rate or pressure of the working gas is set to an appropriate value. It is detected that it is more than
Since the detection signal is used as the construction start signal, there is an effect that, while saving energy, the construction failure caused by the insufficient flow rate or pressure of the working gas, the subsequent treatment, or the disposal of the welding member is prevented.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of a gouging power supply according to an embodiment of the present invention.

FIG. 2 is a block circuit diagram showing an embodiment of a welding power source according to another embodiment of the present invention.

FIG. 3 is a block circuit diagram of a conventional gouging power supply.

FIG. 4 is a block circuit diagram of a conventional welding power source.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Switching control circuit part 2 Switch control circuit part 3 Fan control circuit part 4 Output setting device 5 Air 6 Input power supply 7 Switch 8 Main transformer 9 Fan 10 Switching element 11 Current detector 12 Reactor 13 Interphase reactor 14 Air sensor 15 Air ON / OFF switch 16 Gouging torch 17 Gouging rod 18 Workpiece (base material) 19 Discriminator 20 Start signal output unit 21 Torch switch 22 Welding torch 23 Welding wire 24 Gas valve 25 Wire feeder 26 Shield gas

Claims (21)

[Claims] 1. A step of starting supply of air to a gouging unit, a step of detecting at least one of a flow rate and a pressure of supplied air, and a step of detecting a flow rate or a pressure of the detected air to be equal to or more than a predetermined value. A step of starting the supply of power from the gouging power supply and a step of stopping the supply of power from the gouging power supply after a lapse of a predetermined time from when the detected flow rate or pressure of the air becomes a predetermined value or less. Control method for a gouging power supply. 2. A step of starting the supply of air to the gouging unit, a step of detecting at least one of the flow rate and the pressure of the supplied air, and a step of detecting that the flow rate or the pressure of the detected air is equal to or more than a predetermined value. When the switch for inputting and closing the input is closed and the input voltage is input to the power supply for gouging, and the switch is opened after a lapse of a predetermined time from when the detected flow rate or pressure of the air becomes a predetermined value or less. Shutting off the input of the voltage to the gouging power supply. 3. A step of starting supply of air to the gouging section, a step of detecting at least one of a flow rate and a pressure of the supplied air, and a step of determining whether a flow rate or a pressure of the detected air is equal to or more than a predetermined value. When the switching element for adjusting the output is turned on and the supply of power from the power supply for gouging is started, and after a lapse of a predetermined time from when the detected flow rate or pressure of the air becomes a predetermined value or less, the switching element is Turning off and stopping the supply of power from the gouging power supply. 4. A step of starting supply of air to the gouging section, a step of detecting at least one of a flow rate and a pressure of the supplied air, and a step of detecting that the flow rate or the pressure of the detected air is equal to or more than a predetermined value. When the fan rotates, and when the detected flow rate or pressure of the air becomes equal to or less than a predetermined value or when the output current is stopped, the step of stopping the fan at a predetermined time elapse time from the time starting point. Control method for a gouging power supply. 5. A switch for opening and closing an input, an air sensor for detecting at least one of an air flow rate and a pressure, and an air flow rate or a pressure equal to or more than a predetermined value by using an output of the air sensor as an input. A discriminator for detecting whether the flow rate is less than or equal to, and closing the switch when the flow rate or pressure of the air is equal to or more than a predetermined value by using the output of the discriminator as an input, and when the flow rate or pressure of the air is less than a predetermined value. And a switch control circuit for outputting a signal for opening the switch to the switch after a lapse of a predetermined time from the switch. 6. A switching element for adjusting an output, an air sensor for detecting at least one of an air flow rate and a pressure, and an air flow rate or a pressure equal to or more than a predetermined value when an output of the air sensor is input. A discriminator for detecting whether the flow rate is less than or equal to, and when the output of the discriminator is input, the switching element is turned on when the flow rate or pressure of the air exceeds a predetermined value, and when the flow rate or pressure of the air falls below a predetermined value. After a lapse of a predetermined time from
The gouging power supply according to claim 5, further comprising a switching control circuit unit that outputs a signal to be flipped to the switching element. 7. A fan for cooling the inside of a power supply, an output current detector for detecting an output current, an air sensor for detecting at least one of an air flow rate and a pressure, and an output of the air sensor as an input. A discriminator that detects whether the flow rate or pressure of air is equal to or more than a predetermined value, and the output of the output current detector and the output of the discriminator are input and the flow rate or pressure of air is equal to or more than a predetermined value. A fan control circuit that outputs a signal to the fan to stop the fan at a predetermined time elapse from a time when the fan rotates and the flow rate or pressure of the air falls below a predetermined value or when the output current stops. The gouging power supply according to claim 5 or 6, further comprising a unit. 8. A step of starting supply of a working gas to the welding portion, a step of detecting at least one of a flow rate and a pressure of the supplied working gas, and a step of detecting a flow rate or a pressure of the detected working gas. Starting the supply of power from the power supply when the value becomes equal to or more than the predetermined value, and stopping the supply of power from the power supply after a lapse of a predetermined time from when the detected flow rate or pressure of the working gas becomes equal to or less than the predetermined value. Control method for a welding power source. 9. A step of starting supply of a working gas to a welding portion, a step of detecting at least one of a flow rate and a pressure of the supplied working gas, and a step of detecting a flow rate or a pressure of the detected working gas. When the input voltage is input to the power supply by closing the switch that performs input and output when the value becomes equal to or more than the predetermined value, and after a predetermined time elapses from when the detected flow rate or pressure of the working gas becomes equal to or less than the predetermined value, the switch is operated. Interrupting the input of the open input voltage to the power supply. 10. A step of starting supply of a working gas to a welding portion, a step of detecting at least one of a flow rate and a pressure of the supplied working gas, and a step of detecting a flow rate or a pressure of the detected working gas. A switching element that adjusts the output when the value becomes equal to or more than a value, and turns on the power supply from the power supply to start supplying power from the power source; and the switching operation is performed after a lapse of a predetermined time from when the detected flow rate or pressure of the working gas becomes equal to or less than a predetermined value. Turning off the element and stopping the supply of power from the power supply. 11. A step of starting supply of a working gas to a welding portion or a cutting portion, a step of detecting at least one of a flow rate and a pressure of the supplied working gas, and a step of detecting a flow rate or a detected flow rate of the working gas. A step of rotating the fan when the pressure is equal to or higher than a predetermined value; and a time period starting from when the detected flow rate or pressure of the working gas becomes equal to or lower than the predetermined value or when the output current is stopped. Stopping the fan. 12. A switch for opening and closing an input, an air sensor for detecting at least one of a flow rate and a pressure of a working gas, and a flow rate or a pressure of the working gas which is equal to or more than a predetermined value by using an output of the air sensor as an input. And a discriminator for detecting whether it is less than or equal to, and closing the switch when the flow rate or pressure of the working gas is equal to or more than a predetermined value with the output of the discriminator as an input, and the flow rate or pressure of the working gas is equal to or less than a predetermined value. A welding power supply comprising a switch control circuit for outputting a signal for opening the switch to the switch after a lapse of a predetermined time from when 13. A switching element for adjusting an output,
An air sensor that detects at least one of the flow rate and the pressure of the working gas, and a discriminator that detects whether the flow rate or the pressure of the working gas is equal to or more than a predetermined value with the output of the air sensor as an input. With the output of the discriminator as an input, the switching element is turned on when the flow rate or pressure of the working gas becomes equal to or more than a predetermined value, and the switching element is turned off after a lapse of a predetermined time from when the flow rate or pressure of the working gas becomes equal to or less than the predetermined value. 13. The welding power supply according to claim 12, further comprising a switching control circuit unit that outputs a signal to the switching element. 14. A fan for cooling an inside of a power supply, an output current detector for detecting an output current, an air sensor for detecting at least one of a flow rate and a pressure of a working gas, and an output from the air sensor. A discriminator that detects whether the flow rate or pressure of the working gas is equal to or more than a predetermined value, and an output of the output current detector and an output of the discriminator are input and the flow rate or pressure of the working gas is a predetermined value. When the above occurs, the fan rotates and outputs a signal to the fan to stop the fan at a predetermined time elapse time from when the flow rate or pressure of the working gas becomes equal to or less than a predetermined value or when the output current is stopped. The welding power supply according to claim 12, further comprising a fan control circuit unit that performs the operation. 15. A step of starting the supply of the working gas to the cutting section, a step of detecting at least one of a flow rate and a pressure of the supplied working gas, and a step of detecting a flow rate or a pressure of the detected working gas. Starting the supply of power from the power supply when the value becomes equal to or more than the predetermined value, and stopping the supply of power from the power supply after a lapse of a predetermined time from when the detected flow rate or pressure of the working gas becomes equal to or less than the predetermined value. Control method for the cutting power supply. 16. A step of starting supply of a working gas to the cutting section, a step of detecting at least one of a flow rate and a pressure of the supplied working gas, and a step of determining a flow rate or a pressure of the detected working gas. When the input voltage is input to the power supply by closing the switch that performs input and output when the value becomes equal to or more than the predetermined value, and after a predetermined time elapses from when the detected flow rate or pressure of the working gas becomes equal to or less than the predetermined value, the switch is operated. Cutting off the input of the open input voltage to the power supply. 17. A step of starting supply of a working gas to the cutting section, a step of detecting at least one of a flow rate and a pressure of the supplied working gas, and a step of detecting a flow rate or a pressure of the detected working gas. A switching element that adjusts the output when the value becomes equal to or more than a value, and turns on the power supply from the power supply to start supplying power from the power source; and the switching operation is performed after a lapse of a predetermined time from when the detected flow rate or pressure of the working gas becomes equal to or less than a predetermined value. Turning off the element and stopping the supply of power from the power supply. 18. A step of starting supply of a working gas to the cutting section, a step of detecting at least one of a flow rate and a pressure of the supplied working gas, and a step of detecting a flow rate or a pressure of the detected working gas. The fan stops when the flow rate or the pressure of the detected working gas falls below the predetermined value or when the output current stops, and the fan stops when the predetermined time elapses from when the output current stops. And controlling the power supply for cutting. 19. A switch for opening and closing an input, an air sensor for detecting at least one of a flow rate and a pressure of the working gas, and a flow rate or a pressure of the working gas equal to or more than a predetermined value by using an output of the air sensor as an input. And a discriminator for detecting whether it is less than or equal to, and closing the switch when the flow rate or pressure of the working gas is equal to or more than a predetermined value with the output of the discriminator as an input, and the flow rate or pressure of the working gas is equal to or less than a predetermined value. And a switch control circuit for outputting a signal for opening the switch to the switch after a lapse of a predetermined time from when the switch is turned off. 20. A switching element for adjusting an output,
An air sensor that detects at least one of the flow rate and the pressure of the working gas, and a discriminator that detects whether the flow rate or the pressure of the working gas is equal to or more than a predetermined value with the output of the air sensor as an input. With the output of the discriminator as an input, the switching element is turned on when the flow rate or pressure of the working gas becomes equal to or more than a predetermined value, and the switching element is turned off after a lapse of a predetermined time from when the flow rate or pressure of the working gas becomes equal to or less than the predetermined value. 20. The disconnecting power supply according to claim 19, further comprising a switching control circuit unit that outputs a signal to the switching element. 21. A fan for cooling an inside of a power supply, an output current detector for detecting an output current, an air sensor for detecting at least one of a flow rate and a pressure of a working gas, and an output from the air sensor. A discriminator that detects whether the flow rate or pressure of the working gas is equal to or more than a predetermined value, and an output of the output current detector and an output of the discriminator are input and the flow rate or pressure of the working gas is a predetermined value. When the above occurs, the fan rotates and outputs a signal to the fan to stop the fan at a predetermined time elapse time from when the flow rate or pressure of the working gas becomes equal to or less than a predetermined value or when the output current is stopped. 21. The cutting power supply according to claim 19, further comprising a fan control circuit section that performs the cutting operation.