JPH08185820A - Discharge preventive method in energy particle generator, this discharge preventive structure and energy particle generator - Google Patents

Abstract

PURPOSE: To reduce abnormal discharge, and obtain an constantly stable electron beam by removing moisture or the like adsorbed to an anode by heating the anode when a cathod is replaced in the atmosphere. CONSTITUTION: A cathode installing member 24 and an anode installing member 26 are made openable and closable by a hinge 28, and an electron gun 5 is constituted. When a cathode 23 and a filament 22 are replaced, the electron gun 5 is put in an opening condition. In this condition, the inside of the electron gun is exposed to the atmosphere, and an impure substance such as moisture in the atmosphere is adsorbed to an anode 25. Therefore, the anode 25 is heated by using a hot air heater 44, and the impure substance such as moisture adsorbed to the anode 25 is discharged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge preventing method in an energetic particle generator such as an electron gun, its discharge preventing structure and an energetic particle generator such as an electron beam.

[0002]

2. Description of the Related Art For example, in a video tape recorder, image quality is being improved by high density recording.
In order to cope with this, for example, a so-called vapor deposition tape having a metal magnetic thin film as a magnetic layer has been put into practical use as a magnetic recording medium for 8 mm VTR.

The vapor-deposited tape is superior in magnetic properties to the widely used coating type magnetic tapes and has a thin magnetic layer, so that it is superior to the coating type magnetic tapes in terms of electromagnetic conversion characteristics. It is expected to perform well.

Unlike the coating-type tape, such a vapor-deposited tape, as shown in FIG.
It is manufactured by dissolving a magnetic metal substance such as i and allowing its vapor to uniformly adhere to the tape surface.

That is, in the vacuum chamber 1, the cooling roll 4 is arranged above the evaporation source 6, and the cooling roll 4
The non-magnetic base film 40 is cooled while being in contact with and is conveyed in the direction of the arrow, and at the same time, vapor of magnetic metal from the evaporation source 6 is attached onto the base film 40. In FIG. 13, 2 is a feeding hub around which the base film 40 is wound, 3 is a winding hub, 17 is a guide roll for guiding the base film, and 15 is a crucible for housing the evaporation source 6. The vapor deposition method shown in FIG. 13 is called oblique vapor deposition.

In the vicinity of the cooling roll 4, a window 7a is provided to define the incident angle of vaporized metal and the vapor deposition region and to prevent the vaporized metal from flying to the region in the vacuum chamber where vapor deposition is not desired. A board 7 is arranged. In the figure, 63 is a vacuum pump.

As means for evaporating the magnetic metal,
An electron beam E emitted from an electron gun 5 provided outside the vacuum chamber 1 is used.

This electron gun 5 comprises a cathode mounting member 24 and an anode mounting member 26 as shown in the front view of FIG. 14 and the sectional view of FIG. Cathode mounting member 24
Includes a cathode support cylinder 21B provided on a core member 21A disposed inside from a base end of a cylindrical insulator 20, and a filament 22 and a cathode 23 provided at a tip end portion of the cathode support cylinder 21B. There is. The anode attachment member 26 has a structure in which the anode 25 facing the cathode 23 is attached to the cylindrical body 27. The cathode attachment member 24 and the anode attachment member 26 are openably and closably connected via a hinge 28 to form an electron generation chamber 29.

In the anode mounting member 26, the anode
A coil 30 for controlling the direction of the electron beam E is wound around a cylindrical body 30 provided on the back surface of 25, and a valve 32 for opening and closing the electron generating chamber 29 is provided at the tip.

Further, a cylindrical body 34 having a pump mounting cylindrical body 33 projecting from a part of its circumferential surface is connected and fixed to the outer circumference of the distal end side of the cylindrical body 30. A second vacuum pump 35 is attached to the tip of the pump attachment cylinder 33. Further, a first vacuum pump 37 is attached to a pump attachment cylinder 36 projecting from a part of the circumferential surface of the cylinder 27 on the cathode attachment member 24 side.

In the figure, 38 is a power supply part of the filament 22, and 39 is a cooling water supply jacket part provided in the anode 25. The cathode and anode power supplies are not shown.

In operating the electron gun 5, first,
The first and second vacuum pumps 37 and 35 are driven to make the inside of the electron gun 5 vacuum, and a current is passed through the filament 22 to heat the cathode 23. Next, when a high voltage is applied between the cathode 23 and the anode 25, electrons are accelerated and emitted from the cathode 23 toward the anode 25, and become an electron beam E. When the electron gun 5 is not used, the valve 32 is closed and the electron generating chamber 29 is kept in vacuum.

The electron beam E is for evaporating the evaporation source of the magnetic metal, and therefore needs to have an extremely large power. For this reason, the filament 22 and the cathode 23 that is the electron emission source deteriorate with repeated use, so the electron generation chamber 29 is periodically opened to return to atmospheric pressure,
Exchange. At that time, the anode 25 is cleaned and finished with a volatile solvent such as acetone.

However, when the electron generating chamber 29 is opened and returned to atmospheric pressure, impurities such as moisture and gas in the atmosphere are adsorbed on the surfaces of the filament 22, cathode 23 and anode 25.

Of the adsorbed impurities, those adsorbed on the filament 22 and the cathode 23 are heated to a high temperature by the electric current when the operation of the electron gun 5 is started again. Due to the heat, the gas is quickly degassed and then discharged to the outside by the vacuum pumps 35 and 37.

However, since the temperature of the anode 25 is not as high as that of the filament or the cathode 23, the anode 25
Impurities adsorbed on 25 are not immediately degassed. Therefore, the impurities released from the anode 25 during the subsequent operation of the electron gun float in the electron generation chamber 29, and this is the electron gun 5.
It may cause abnormal discharge inside.

When this abnormal discharge occurs, the electron beam E from the electron gun 5 is powered down by the amount of energy consumed by the abnormal discharge, so that the evaporation amount from the magnetic metal evaporation source decreases and the base There was a problem that the film thickness of the magnetic metal adhered on the film 40 becomes thin. This makes recording and reproduction uncertain at this location.

[0018]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and enables impurities to be promptly and surely released from an electrode portion such as an anode to prevent troubles such as abnormal discharge. An object of the present invention is to provide a method for preventing discharge in an energetic particle generator, a structure for preventing the discharge, and an energetic particle generator.

[0019]

The present invention has the following constitution in order to achieve the above object.

The present invention is a first aspect of emitting energetic particles.
At least the second electrode in an energetic particle generator (eg, electron gun 5 described below) having an electrode part (eg cathode 23 described below) and a second electrode part (eg anode 25 described below) facing the electrode part The present invention relates to a discharge prevention method in an energetic particle generator, in which impurities (eg, adsorbed gas) are released from the heated portion by heating the portion.

According to the present invention, the electron gun is formed by the cathode mounting member and the anode mounting member, and the cathode mounting member is configured to be opened and closed relative to the anode mounting member. In, it is preferable that the anode is heated to perform degassing.

In the above, the cathode mounting member can be opened with respect to the anode mounting member, the cathode can be replaced, and the anode can be heated to perform degassing.

Further, in the above, the cathode attachment member is opened with respect to the anode attachment member to replace the cathode, and then the cathode attachment member is closed with respect to the anode attachment member to heat the anode. It is also possible to degas.

In the present invention, the heating of the anode can be performed by blowing hot air.

The present invention also provides a discharge prevention structure for implementing the above method.

In the discharge prevention structure according to the present invention, it is preferable to have an anode heating means inside and / or outside the electron gun.

In the above structure, the heating means for the anode may be a hot air blower.

In the above structure, the heating means for the anode may be a heater.

In the above, it is preferable that the heater is arranged inside and / or outside the electron generating chamber.

In the above, the heater can be attached to the cathode side.

In the above, the heater may be attached to the anode side.

In the above, it is preferable that the anode heating means is hot water supply means.

Further, in the above, cold water supply means for supplying cold water for cooling the anode can be used as the hot water supply means.

Furthermore, the present invention also provides an energetic particle generator having the above structure.

In the above device, an energetic particle generating device configured as an electron gun can be used.

[0036]

Embodiments of the present invention will be described below.

1 to 5 illustrate the first embodiment. 13 to 15 are denoted by the same reference numerals, and the description thereof may be omitted (the same applies to the second and subsequent embodiments described later).

This example is an example in which the present invention is applied to the electron gun of the vacuum vapor deposition apparatus for manufacturing the vapor deposition tape described above, and the structure of the vapor deposition tape is shown in FIG. That is, the metal magnetic thin film 41 is formed on one surface of the non-magnetic base film 40. And
It is preferable that a back coat layer 42 shown by an imaginary line is formed on the other surface of the base film.

Ferromagnetic metal materials used for forming the metal magnetic thin film 41 are Fe, Co, Ni and Cr.
In addition to metals such as Co-Ni alloy, Co-Pt alloy, C
o-Ni-Pt alloy, Fe-Co alloy, Fe-Ni alloy, Fe-Co-Ni alloy, Fe-Co-B alloy, Co
-Ni-Fe-B alloy, Co-Cr alloy, or those containing metals such as Cr and Al in these alloys.
In particular, when a Co—Cr alloy is used, a perpendicular magnetization film is formed. The thickness of the metal magnetic thin film 41 is usually 0.02 to 1 μm.

The material for the back coat layer 42 has a pH of
DBP oil absorption of 80cc / 100 at 6.0 or above (especially 6.0 to 10.0)
Carbon black of g or less is suitable for preventing the formation of rust. The thickness of the back coat layer is preferably 0.4 to 1.2 μm.

FIG. 3 is a sectional view of the vacuum vapor deposition device.

Inside the vacuum chamber 1, a cooling roll 4 and an evaporation source (a metal housed in the crucible 15, for example, a Co-Ni alloy) 6 are arranged, and in the vicinity of the cooling roll 4, the lower right side in FIG. The deposition prevention plate 7 is fixed in position.
In the vacuum chamber 1, the feeding hub 2 wound with the base film 40 and the winding hub 3 having the tip of the base film 40 attached are attached. The base film between the hubs 2 and 3 is rotated by the rotation of the winding hub 3. , Is brought into close contact with most of the outer peripheral surface of the cooling roll 4, and then wound onto the winding hub 3.

The base film 40 is guided by a large number of guide rolls 17 between the feeding hub 2 and the take-up hub 3 and the cooling roll 4 and is given an appropriate tension so that the cooling roll 4 can be removed from the feeding hub 2. It travels to the winding hub 3 via.

The protection plate 7 is provided with windows 7a and 7b, and the electron beam E emitted from the electron gun 5 provided outside the vacuum chamber 1 irradiates the evaporation source 6 through the window 7b. Thus, the evaporated metal flies from the evaporation source 6, passes through the window 7a, and adheres to the base film 40 running on the cooling roll 4 in the area of the window 7a. It becomes the metal thin film 41.

The basic structure of the electron gun 5 is shown in FIG. 14 and FIG.
It has the same configuration as shown in 15. The electron gun 5 is a dolly.
It is attached to the upper part of 43 and can be attached to and detached from the vacuum chamber 1.

In this example, it should be noted that, as shown in FIG. 1, when the electron generating chamber 29 is opened for replacing the cathode 23, the anode 25 is blown by the warm air blower 44.
Is to heat. The hot air is preferably 200 to 600 ° C., and is preferably blown over the entire anode 25. In the method of heating only the local portion of the anode 25 to a high temperature with a burner or the like, since the anode 25 is water-cooled by the water-cooling jacket 39, dew condensation occurs due to cooling after completion of heating, and the degassing effect cannot be obtained. Further, the surface is oxidized, which is not preferable.

FIG. 2 shows a state in which the electron generating chamber 29 is closed and the electron gun 5 is operating. Since the anode 25 is preheated as described above to remove impurities such as moisture adsorbed in the atmosphere, the discharge is less likely to occur in the electron gun 5. Therefore, the electron beam is always emitted stably, the thickness of the magnetic metal thin film is stabilized, and the quality of the magnetic tape is guaranteed.

As shown in FIG. 4, for example, the warm air blower 44 has a power cord 45 connected to a power supply section 58 provided on the carriage 43 and is detachably hung on a hook 46 provided on the carriage 43. For example, it is convenient to attach it to the electron gun 5. That is, the warm air blower 44 is removed from the hook 46 at the time of heating the anode, and is hung on the hook 46 at other times.

According to this example, there is an advantage that the degassing of the anode 25 can be achieved without special processing of the electron gun 5.

Next, a second embodiment will be described with reference to FIGS. 6 and 7. In this example, a heater 47 as a heating means for the anode 25 is attached on the cathode 23 side, that is, on the outer peripheral surface of the tip of the cathode support cylinder 21B. Since the heater 47 is distant from the anode to be heated, it is preferable to use a far infrared heater having good heating efficiency in this state.

FIG. 6 shows a state in which the heater 47 is operated to heat the anode 25 when the electron gun 5 is opened to replace the cathode 23. In this case, heating by the warm air fan 44 shown by a virtual line may be used together.

FIG. 7 shows a state in which the electron gun 5 is closed and the heater 47 is operated after the cathode 23 is replaced. In this case, the impurities such as the water separated from the anode 25 by the heating by the heater 47 are discharged to the outside of the electron gun by the vacuum pumps 35 and 37 until the inside of the electron gun reaches a predetermined vacuum degree. Therefore, abnormal discharge does not occur.

According to this example, since the heater 47 is built in the electron gun 5, degassing can be easily performed without requiring special labor. The far infrared heater may be provided outside the electron gun, or may be provided both inside and outside the electron gun.

In any of the following examples,
Similarly to the above, the heating means of the anode 25 can be used in either the open state or the closed state of the electron gun 5, as described above.

Next, a third embodiment will be described with reference to FIG. In this embodiment, the PTC (Positi
ve Temperature Coefficient) element 48 is arranged. This PTC element 48 is made of ceramics such as barium titanate, and has a positive temperature coefficient of resistance, which is convenient. Others are the same as those in the second embodiment, and similar effects can be obtained.

In the fourth embodiment, a heating wire 49 is arranged in the anode 25 as shown in FIG.

Also in this example, the same effect as in the second embodiment can be obtained.

Next, a fifth embodiment will be described with reference to FIG. In this example, the heating means for the anode 25 is supplied with hot water by using the water cooling jacket 39 of the existing cold water supply means for supplying cold water for cooling the anode 25. That is, a hot water pipe 51 is connected to the jacket 39 via a three-way valve 50, and a throw-in heater 53 is arranged in a hot water tank 52 connected to the hot water pipe 51.

When heating the anode 25, the three-way valve 50 is switched to jacket the hot water from the hot water tank 52.
Supply to 39. Others are the same as those in the second to fourth embodiments, and similar effects can be obtained.

In the sixth embodiment, as shown in FIG. 11, a water heater 54 using city gas or the like as a heat source instead of the hot water tank 52 is used.
Is provided. Others are the same as those in the fifth embodiment.

According to the fifth and sixth embodiments described above, since the existing water cooling jacket is simply used, it is not necessary to process the electron gun 5 and the operation is simple.

Next, a seventh embodiment will be described with reference to FIG. In this example, the cathode 23 is configured to have a variable angle (an angle changing mechanism is not shown), and the electron beam E ′ is directly applied to the anode 25 to heat and degas. It goes without saying that the power of the electron beam E'when heating the anode is made to be significantly smaller than the power of the electron beam E at the time of vapor deposition.

As a modification of the seventh embodiment, the electron beam E'may be deflected by appropriate means and applied to the anode 25. Further, the electron beam deflection and the angle variable cathode may be combined.

According to this example, degassing can be achieved by a simple operation without requiring special labor.

In each of the above-described embodiments, when heating the anode, the electron gun constituent parts other than the anode (for example, the inner wall surface of the electron generation chamber) are also heated, and this part is degassed. Not to mention the good things.

The present invention can be applied to other appropriate devices such as a cathode ray tube (CRT) and an electron microscope in addition to the above electron gun for a vacuum vapor deposition device, and further to an energy particle generator other than the electron gun. Is similarly applicable.

[0067]

According to the present invention, at least the second electrode portion of the first electrode portion emitting the energetic particles and the second electrode portion facing the first electrode portion is heated so that the impurities are emitted from the heated portion. Therefore, the discharge caused by the impurities is prevented. As a result, the energy particles emitted from the first electrode portion are not affected by the discharge and are stably supplied from the energy particle generator.

[Brief description of drawings]

FIG. 1 is a perspective view of an essential part of an electron gun according to a first embodiment in an open state.

FIG. 2 is a sectional view of the electron gun in a closed state.

FIG. 3 is a cross-sectional view of the vacuum vapor deposition device.

FIG. 4 is a partial front view of a vacuum vapor deposition device of an example in which a warm air fan is attached to the electron gun.

FIG. 5 is a sectional view of the vapor-deposited magnetic tape.

FIG. 6 is a perspective view of an essential part of an electron gun according to a second embodiment in an open state.

FIG. 7 is a sectional view of the electron gun in a closed state.

FIG. 8 is a sectional view of an electron gun according to a third embodiment.

FIG. 9 is a front view of a main part of an electron gun according to a fourth embodiment.

FIG. 10 is a front view of a main part of an electron gun according to a fifth embodiment.

FIG. 11 is a front view of a main part of an electron gun according to a sixth embodiment.

FIG. 12 is an enlarged sectional view of an essential part of an electron gun according to a seventh embodiment.

FIG. 13 is a schematic cross-sectional view of a conventional vacuum vapor deposition device.

FIG. 14 is a front view of a main part of the electron gun.

FIG. 15 is a sectional view of the same.

[Explanation of symbols]

 5 ... Electron gun 22 ... Filament 23 ... Cathode 24 ... Cathode mounting member 25 ... Anode 26 ... Anode mounting member 28 ... Hinge 29 ... Electron generation chamber 35, 37・ ・ ・ Vacuum pump 39 ・ ・ ・ Water cooling jacket 40 ・ ・ ・ Base film 41 ・ ・ ・ Metal magnetic thin film 44 ・ ・ ・ Air heater 47 ・ ・ ・ Far infrared heater 48 ・ ・ ・ PTC element 49 ・ ・ ・ Electricity Heat wire 51 ・ ・ ・ Hot water supply pipe 52 ・ ・ ・ Hot water tank 53 ・ ・ ・ Drop heater 54 ・ ・ ・ Hot water heater E, E '・ ・ ・ Electron beam

Claims (16)

[Claims] 1. An energetic particle generator having a first electrode part for emitting energetic particles and a second electrode part facing the first electrode part, wherein at least the second electrode part is heated to remove impurities from the heated part. Release quality,
Discharge prevention method in energetic particle generator. 2. An electron gun configured so that an electron generating chamber is formed by the cathode mounting member and the anode mounting member, and the cathode mounting member is opened and closed relative to the anode mounting member. The method of claim 1, wherein the anode is heated for degassing. 3. The method according to claim 2, wherein the cathode mounting member is opened with respect to the anode mounting member, the cathode is replaced, and the anode is heated to perform degassing. 4. The cathode mounting member is opened with respect to the anode mounting member to replace the cathode, and then the cathode mounting member is closed with respect to the anode mounting member to heat the anode to degas. The method according to claim 2, wherein 5. The method according to claim 3, wherein the heating of the anode is performed by blowing hot air. 6. A discharge prevention structure for implementing the discharge prevention method according to claim 1. Description: 7. The structure according to claim 6, further comprising heating means for the anode inside and / or outside the electron gun. 8. The structure according to claim 7, wherein the heating means of the anode is a hot air blower. 9. The structure according to claim 7, wherein the heating means of the anode is a heater. 10. The structure according to claim 9, wherein the heater is arranged inside and / or outside the electron generating chamber. 11. The structure according to claim 10, wherein the heater is attached to the cathode side. 12. The structure according to claim 10, wherein the heater is attached to the anode side. 13. The structure according to claim 7, wherein the heating means of the anode is a hot water supply means. 14. The structure according to claim 13, wherein the cold water supply means for supplying cold water for cooling the anode is also used as the hot water supply means. 15. An energetic particle generator having the discharge prevention structure according to claim 6. 16. The device according to claim 15, configured as an electron gun.