JPH0777609B2 - Electric discharge cleaning device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electric discharge cleaning apparatus, and more particularly, to automatically start and stop electric discharge and automatically control current, voltage, pressure or gas flow rate during electric discharge. The present invention relates to a discharge cleaning apparatus suitable for performing the cleaning.

[Conventional technology]

For example, in the conventional discharge cleaning apparatus described in Japanese Patent Publication No. 58-33009, at the start of discharge, gas introduction, cathode heating,
It was necessary to adjust the voltage applied to each electrode, and these reverse operations were necessary when the discharge was stopped. Then, in order to perform stable discharge, the current of each electrode,
The voltage and pressure inside the vessel had to be constantly monitored and adjusted. Further, in order to prevent the spattering phenomenon on the wall surface of the container, the potential difference between the anode electrode and the wall surface of the container is made as small as possible.

[Problems to be Solved by the Invention]

In the above-mentioned conventional electric discharge cleaning device, since all procedures for stably performing electric discharge rely on human beings, the operation is complicated, and it is necessary for a person to constantly monitor the device, which requires a lot of labor. there were. In addition, since it is designed so that spatter does not occur between the anode electrode and the container, the container is not damaged, but the gas molecules adhering to the container wall cannot be sufficiently removed, and it is necessary to heat the container wall after all. Occurs.

An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a discharge cleaning apparatus capable of automatically controlling the start and stop of discharge and the current, voltage, pressure (or gas flow rate) during discharge. To provide. Another object of the present invention is to provide an electric discharge cleaning device capable of effectively cleaning the container wall surface by positively colliding the ions generated by the discharge with the container wall surface.

[Means for Solving the Problems]

In order to achieve the above object, the present invention provides a first power source for heating a cathode and a cathode and an anode having a plurality of through holes arranged so as to cover the cathode and housed in a vacuum container. And a gas introduction device for introducing gas into the vacuum container, wherein a second power source for making the anode a positive potential is the anode and a third power source for making the cathode a negative potential is provided. A power source is connected to each of the cathodes, a negative side of the second power source, a positive side of a third power source, and the vacuum vessel are connected, and the first and second discharge sources are connected according to the procedure from the start to the end of the discharge cleaning. A first to a third power supply and a control device that controls the gas introduction device in sequence are provided, and a current-voltage regulator that adjusts the current and voltage during discharge is provided.

[Action]

A sequencer is used to configure conditions such as gas introduction, cathode heating, voltage application to each electrode and timing based on conditions for stable and continuous discharge, and the set conditions are reached by activating this sequencer. Then, the discharge is automatically started, and the discharge is stably continued by automatically adjusting the cathode heating power source during the discharge. Then, when the set time has elapsed, the discharge is automatically stopped, so if the discharge cleaning is started, the discharge cleaning is automatically performed. Also, since the negative side of the power source of the anode electrode and the positive side of the cathode power source and the container were connected, electricity generated from the cathode also flew between the anode and the container, colliding with the wall surface of the container and gas molecules adhering to the wall surface of the container. Effectively removes from the wall. Since the potential difference between the anode and the cathode and the potential difference between the anode and the container can be controlled by the current-voltage regulator and the controller, excessive sputtering on the container can be prevented and the container is not damaged.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. First
The figure shows the configuration. The stainless steel vacuum container 1 for electric discharge cleaning is evacuated by the vacuum pump 2 and the pressure is measured by the vacuum gauge 3. The electrode for discharge is the hot cathode 4 of tungsten wire.
And stainless steel mesh anode 5. The hot cathode 4 is heated by the power source 11 and has a negative potential by the power source 12.
The anode 5 is brought to a positive potential by the power supply 13. And
The negative side of the power source 13, the positive side of the power source 12, and the container 1 are connected so as to have the same potential, and this common potential is grounded. As a result, the cathode 4 is always kept at the potential and the anode 5 is kept at the positive potential. These power supplies 11,12,
13 is controlled by the current / voltage regulator 9 and the controller 10. Argon gas is used as the discharge gas 7 and flows into the vacuum container 1 through the flow rate regulator 8 and the valve 6.
The flow controller 8 is controlled by the controller 10.

FIG. 2 shows an example of an electric circuit of the controller 10. First, when the vacuum pump 2 is operated to reach a predetermined pressure and then the switch 21 is pressed, the relay R ₀ is operated and the contacts R _0a and R _0d are closed. When the switch R _0a is closed, the circuit AA ′ for controlling the flow rate regulator 8 is connected to turn on the flow rate regulator 8, and the gas 7 flows into the vacuum container 1 at the set flow rate. The circuit F-F of the timer T ₃ to set the discharge cleaning time 'is activated and energized. When the pressure in the container 1 reaches the set value of the vacuum gauge 3, the contact 22 closes, the relay R ₁ operates, and the contacts R _1a , R
_1b and R _1c are closed. As a result, the circuit BB 'is connected to operate the current / voltage regulator 9, and the circuit CC' for controlling the power supply 11 of the hot cathode 4 is connected to set the timer T ₁ for setting the time for turning on the power supplies 12 and 13. , T ₄ starts operating. Timer T ₁
After the set time t ₁ of the above, the circuit DD ′ for controlling the power supply 12 of the hot cathode 4 is connected, and after the set time t ₄ of the timer T ₄ passes, the circuit EE ′ for controlling the power supply 13 of the anode 5 is connected. Connected, each power supply is turned on, and discharge begins. The current and voltage during discharging are controlled by the current / voltage regulator 9. When the set time of timer T ₃ reaches t ₃ , relay R ₂ operates and contact R
_2a is closed, contacts _R2b and _R2c are opened, and the discharge ends. The timer T ₂ is activated at the same time as the relay R _{2 is} activated, and when the time t _{2 has} elapsed, the contacts T _2a , T _2b , T _2c are opened, and the current / voltage regulator 9 and the power supply 11 are turned off.
It becomes FF, and the gas flow rate regulator 8 is closed.

If it becomes necessary to cut off the discharge before the discharge time t ₃ set in the timer T ₃ has elapsed, the switch 21 is pressed again. Then, the relay R ₂ is activated, and after t ₂ hours, the timer T ₂ is activated to end the discharge.

In this embodiment, discharge cleaning is started after the pressure inside the vacuum container becomes 2 × 10 ⁻⁵ Torr or less, and the pressure during discharge is 2 × 10 ^−3.
Torr and timer T ₁ and T ₂ are both set to 1 minute, timer T ₃ is 3
Time, timer T ₄ is set to 2 minutes.

As described above, according to this embodiment, only by turning on the switch 21 of the controller 10, it is possible to automatically perform discharge cleaning under preset conditions.

〔The invention's effect〕

The following effects can be obtained by performing discharge cleaning using the apparatus according to the present invention.

(1) Discharge cleaning can be performed only by operating the start switch.
Since the discharge condition is monitored by an automatic device, the labor of the operator can be greatly reduced.

(2) It is possible to prevent damage to the container due to a rise in voltage during discharge and excessive current flow.

(3) Since the electrons generated at the cathode collide with the gas molecules that are accelerated by the anode and adhere to the wall surface of the container, the gas molecules can be expelled from the wall surface and a clean wall surface can be easily obtained.

[Brief description of drawings]

FIG. 1 is a block diagram of a discharge cleaning apparatus of the present invention, and FIG. 2 is a circuit example of a controller of the discharge cleaning apparatus of the present invention. 4 ... Cathode, 5 ... Anode, 7 ... Discharge gas, 8 ... Flow rate regulator, 9 ... Current / voltage regulator, 10 ... Discharge cleaning controller, 11 to 13 ... Power supply, 21 ... Switch.

Claims (1)

[Claims] 1. A cathode (4), and an anode (5) which is arranged so as to cover the cathode and has a plurality of through holes, are housed in a vacuum container (1), and the cathode is heated. Power supply (1
1) and a gas introduction device (8) for introducing a gas into the vacuum container, wherein a second power source (13) for setting the anode to a positive potential is used as the anode and the cathode is used as the cathode. A third power source (12) having a negative potential is connected to each of the cathodes, the negative side of the second power source, the positive side of the third power source and the vacuum container are connected, and the discharge cleaning is started. A control device (10) for sequence-controlling the first to third power supplies and the gas introduction device, and a current-voltage regulator (9) for adjusting current and voltage during discharge in accordance with the procedure from the end to the end. An electric discharge cleaning device comprising: