JPH1174153A - Vacuum capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain the surface of a vacuum capacitor and a bellows from rising in temperature and to make the vacuum capacitor large in current value by a method, wherein a hollow water-cooled flange is provided coming into close contact with the outer side of a stationary-side mounting conductor, and cooling water is made to flow through the flange. SOLUTION: A hollow water-cooled flange 17 is mounted, so as to come into close contact with nearly all the outer side of a stationary-side mounting conductor 3. At this point, the water-cooled flange 17 is formed flat so as to be improved in adhesion to the stationary-side mounting conductor 3 and formed into a disc-like or rectangular plate-like hollow structure where a water pool is formed. The water-cooled flange 17 is formed of copper, silver, or aluminum and provided with a cooling-water inlet 17a and an outlet 17b. Cooling water is made to flow into the water-cooled flange 17 from the inlet 17a to the outlet 17b for cooling down the surface of a vacuum capacitor. With this setup, the vacuum capacitor is decreased in surface temperature, so that a connecting conductor and a support insulator can be lessened in heat resistance properties.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum capacitor used for an oscillation circuit of a high-power transmitter, a high-frequency power supply circuit for a semiconductor manufacturing device, a tank circuit of an induction heating device, and the like.

[0002]

2. Description of the Related Art As a device for stabilizing the withstand voltage and capacitance characteristics of a vacuum capacitor and reducing the overall length,
There is one proposed by the present applicant in Japanese Patent Application No. 6-233912, which will be described with reference to FIGS. In the figure, reference numeral 1 denotes a cylindrical vacuum vessel having an interior evacuated, and is formed by tightly attaching a fixed-side mounting conductor 3 and a movable-side current collector 4 to both ends of a cylindrical portion 2. Also, cylindrical part 2
Are formed by joining copper cylinders 2b and 2c to both ends of an insulating cylinder 2a made of ceramic or the like. On the inner surface side of the fixed-side mounting conductor 3, a plurality of cylindrical electrode plates F ₁ ,
F _2, ... a coaxially forms a fixed electrode 5 is attached with a predetermined distance, also the diameter to be inserted and out without contact to each electrode plates of the fixed electrode 5 is different cylindrical electrode plate M ₁ , M ₂ ,... Are concentrically mounted on the movable-side mounting conductor 6 to form the movable electrode 7.

[0003] Reference numeral 8 denotes a guide pin erected at the center of the inside of the fixed-side mounting conductor 3, that is, at the axis of the fixed electrode 5. The guide 9 is provided with a fitting hole 9a that slidably fits with the guide pin 8. An insertion hole 4a is provided at the center of the movable-side current collector 4, and one end of a cylindrical screw receiving portion 10 is attached to the inner surface of the movable-side current collector 4 at a peripheral portion of the insertion hole 4a. The other end of the screw receiving portion 10 is provided with a flange portion 10a. 11 is a screw part 11
a one end of which is fitted and fixed in a fitting hole 12a of a movable lead 12 formed integrally with the guide pin portion 9, and a screw portion 11a is fitted to a flange portion 10a of the screw receiving portion 10. It is inserted. The fitting holes 9a and 12a are continuously formed to have the same diameter. Reference numeral 13 denotes an adjustment nut having a screw hole 13a.
a is inserted into the flange 10a and screwed into the screw hole 13a.
One end of the adjusting nut 13 is connected to the flange 10 via a bearing 14.
a is rotatably supported on the outer surface side.

[0004] Further, a threaded portion 11a of the movable lead bolt 11 is provided.
Is provided with a screw hole 11b at the end thereof, and an adjusting screw 15 is screwed into the screw hole 11b. Screw hole 1 in adjustment nut 13
A large-diameter hole 13b having a diameter larger than 3a is provided. 1
A cylindrical member 6 is located on the outer peripheral side of the movable lead 12, the movable lead bolt 11, and the screw receiving portion 10, and has one end hermetically attached to the movable current collector 4 and the other end hermetically attached to the movable lead 12. It is a bellows that can expand and contract and keep the outer periphery airtight.

[0005] The cylindrical portion 2 may be formed entirely of an insulating tube of ceramic or the like. In addition, it is necessary to insulate between the guide pin 8 and the guide part 9, and in order to maintain slidability, for example, the guide pin 8 may be formed of ceramic such as alumina, and the guide part 9 may be formed of phosphor bronze. The guide pin 8 may be made of metal and its surface may be coated with a nylon resin having excellent lubricity. The movable lead 12 is formed of a conductor. Therefore, when the guide part 9 is made of an insulating material, the guide part 9 and the movable lead 12 are naturally separate bodies.

In the vacuum capacitor having the above configuration, when adjusting the maximum capacitance value, the adjusting nut 1 is screwed before the adjusting screw 15 is screwed into the screw hole 11 b of the movable lead bolt 11.
3 is slightly rotated (in the case of a right-handed screw, clockwise rotation), the tip 8a of the guide pin 8 and the upper end face 11 of the movable lead bolt 11 are rotated.
a slightly movable lead 1 from the maximum capacitance position where b contacts
Move 2 down to adjust to the defined maximum capacitance value. This slight adjustment amount is determined by the degree of variation in the capacitance of the vacuum capacitor. Next, in this state, the adjusting screw 1
5 is the screw hole 13a of the adjusting nut 13
The adjusting screw 15 is screwed into the screw hole 11b until it comes into contact with the stepped portion 13c formed between the movable lead bolt 11 and the large-diameter hole 13b. The rising position of the bolt 11 is regulated. The adjusting screw 15 and the adjusting nut 13 are free.

As described above, by regulating the rising position of the movable lead bolt 11, the maximum capacitance value can be adjusted for each vacuum capacitor even if the maximum capacitance value of the manufactured vacuum capacitors varies. As a result, a vacuum capacitor having a quality that matches the defined maximum capacitance value is obtained.
In addition, even if the adjustment nut 13 is turned rightward from the maximum capacitance position, even if the adjustment nut 15 is turned to the left, the adjustment screw 15 comes into contact with the step 13c and the adjustment nut 13 cannot be turned to the left.
The adjusting nut 15 is a movable lead bolt 11
Functioning as a stopper for preventing the capacitance value from falling out, and preventing the capacitance value from exceeding a defined maximum capacitance value.

In adjusting the capacitance of the vacuum capacitor, when the adjusting nut 13 is rotated clockwise, for example, the movable lead bolt 11 is lowered, and the electrode plates F ₁ , F ₂ ,... And the electrode plates M ₁ , M ₂ are moved. ,…, The intersection length decreases, the capacitance decreases,
Conversely, when the adjustment nut 13 is rotated counterclockwise, the capacitance increases.

In the vacuum capacitor, a force for pushing the movable lead bolt 11 upward always acts due to a pressure difference from the vacuum, and a similar force acts on the adjusting nut 13 screwed with the movable lead bolt 11. Surface pressure is generated on the outer surface of the portion 10a,
The rotation of the adjustment nut 13 requires a large rotation torque. However, since the bearing 14 is provided between the adjustment nut 13 and the outer surface of the flange portion 10a, the rotation becomes easy and a small rotation torque is required. Further, since the screw receiving portion 10 is provided so as to protrude inward from the movable-side current collector 4, the movable lead bolt 1 is provided.
1 moves on the inner surface of the flange 10a of the screw receiving portion 10 with the contact surface 1
1c is brought into contact, and the size can be reduced.
Further, the provision of the guide pins 8 and the guide portions 9 allows the movable electrode 7 to move in parallel with the fixed electrode 5 and stabilize the withstand voltage and the capacitance. The current of the vacuum capacitor is transferred from the fixed-side mounting conductor 3 via the fixed electrode 5 and the movable electrode 7 to the movable-side mounting conductor 6 and the movable lead 12.
Flows through the bellows 16 to the movable-side current collector 4.

[0010]

As described above, in a vacuum capacitor, a current flows through the bellows 16 due to its structure, but the bellows 16 is made of a thin metal (for example, a copper-based or stainless-based metal coated with copper). ), The current-carrying capacity is not so large, so that the current-carrying capacity of the vacuum capacitor is determined by the bellows 16. FIG. 13 shows the surface temperature-conduction current characteristic d of the vacuum capacitor (current frequency 1).
3.6 MHz), the bellows 1
6, the heat generated by the bellows 16 increases, and the heat is conducted to the surface of the vacuum capacitor, thereby increasing the surface temperature. The equivalent circuit of the vacuum capacitor is represented by a series circuit of a resistor R (mainly a resistor of the bellows 16), an inductance L and a capacitance C. When the bellows 16 generates heat as described above, the resistance of the bellows 16 is reduced. Increased dielectric loss tan of vacuum capacitor
δ = ωCR also increased, and a good function as a vacuum capacitor was lost. In addition, due to an increase in the surface temperature of the vacuum capacitor, heat resistance is required for a conductor and a supporting insulator connected to the vacuum capacitor.

On the other hand, in recent years, the capacity of a high-frequency power supply for a semiconductor manufacturing apparatus has been increased, and accordingly, the current of a vacuum capacitor has been required to be increased. For this reason, it is necessary to increase the power supply capacity of the bellows 16, and it is necessary to increase the diameter of the bellows 16 and increase the power supply area. However, when the diameter of the bellows 16 is increased, the self-closing force of the bellows 16 generated from the differential pressure between the vacuum side and the atmosphere side increases, the rotational torque of the adjusting nut 13 for adjusting the capacitance also increases, and the adjusting nut 13 When the motor is rotated by a motor, the size of the motor is also increased.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and can suppress the temperature rise of the surface and the bellows, can increase the allowable current value, and improve the performance. It is an object to obtain a vacuum capacitor that can be used.

[0013]

According to a first aspect of the present invention, there is provided a vacuum capacitor provided with a hollow water-cooled flange in close contact with an outer surface of a fixed-side mounting conductor, through which cooling water flows. It was made.

According to a second aspect of the present invention, a hollow water-cooled flange is provided in close contact with the outer surface of the movable-side current collector, and cooling water flows through the water-cooled flange.

According to a third aspect of the present invention, a hollow water cooling flange is provided in close contact with the outer surface of the fixed side mounting conductor and the movable side current collector, and cooling water flows through each of the water cooling flanges. Things.

According to a fourth aspect of the present invention, the water-cooled flange is formed of any one of copper, silver and aluminum.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1A and 1B are a vertical sectional view and a plan view, respectively, of a vacuum capacitor according to a first embodiment.
Is a hollow water-cooled flange that is attached in close contact with almost the entire outer surface side of it, and has a disc-shaped or square-plate-shaped hollow structure so that it is flattened to improve the adhesion and a pool is formed. . The water cooling flange 17 is formed of any one of copper, silver, and aluminum, and is provided with a cooling water inlet 17.
a and an outlet. Other configurations are the same as the conventional one.

FIG. 2A shows the surface temperature-current value characteristic of the vacuum capacitor according to the first embodiment. In the first embodiment, the water-cooled flange 17 is provided on the outer surface side of the fixed-side mounting conductor 3 as described above. The cooling water flows in from the inlet 17a and flows out from the outlet 17b, so that the surface of the vacuum condenser is cooled. For this reason, as shown in the characteristic a, the surface temperature of the vacuum capacitor is reduced for the same current value as compared with the conventional characteristic d, and the heat resistance of the connecting conductor and the supporting insulator can be reduced.
In addition, the bellows 1
6 is also indirectly cooled, the dielectric loss due to the increased resistance is reduced, and a capacitor with good performance is obtained.

On the other hand, when an arbitrary temperature is set as the allowable temperature of the surface temperature, the allowable value of the current flowing through the vacuum capacitor increases, and the present invention can be applied to a large-capacity high-frequency power supply. It is not necessary to increase the diameter, and the rotational torque of the adjustment nut 13 can be reduced. Further, the water cooling flange 17 is made of copper having good heat conductivity,
Since it is formed of silver and aluminum, the cooling efficiency can be increased.

Embodiment 2 FIGS. 3 (a) and 3 (b) show a longitudinal sectional view and a bottom view of a vacuum capacitor according to Embodiment 2;
It is a hollow water-cooled flange that is attached in close contact with almost the entire outer surface side, and has a disk-shaped or square-plate-shaped hollow structure so as to form a flat shape to improve adhesion and to create a pool. I do. The water cooling flange 18 is formed of any one of copper, silver and aluminum, and is provided with the cooling water inlet 1.
8a and an outlet 18b. Other configurations are the same as the conventional one.

In the second embodiment, the water-cooled flange 18 is also used.
The cooling water is caused to flow from the inlet 18a to the outlet 18b, so that the surface of the vacuum capacitor can be cooled, and the surface temperature-current value characteristic becomes as shown in FIG. The effect of the first embodiment can be further enhanced. This is because the rise in the surface temperature of the vacuum capacitor is mainly due to radiant heat from the bellows 16 which is a heating element. In the first embodiment, the fixed-side mounting conductor 3 closer to the insulating cylinder 2a having poor heat conduction is cooled. Therefore, the overall cooling effect is small.

Embodiment 3 FIG. 4 is a longitudinal sectional view of a vacuum capacitor according to Embodiment 3, in which water-cooling flanges 17 and 18 are attached to the outer surfaces of the fixed-side mounting conductor 3 and the movable-side current collector 4. Accordingly, in this case, the characteristics shown in FIG. 2C are obtained, and the cooling effect can be further enhanced, and the effect can be further enhanced compared to the first and second embodiments.

Embodiments 4 to 6 FIGS. 5 to 7 show longitudinal sectional views of vacuum capacitors according to Embodiments 4 to 6. In Embodiment 4, a water-cooling flange 17 is mounted on the fixed-side mounting conductor 3, and in Embodiment 5, it is movable. A water-cooled flange 18 is attached to the side current collector 4, and both are attached in the sixth embodiment. However, the difference from the first to third embodiments is that the position of the insulating cylinder 2a in the cylindrical portion 2 is close to the movable-side current collector. Therefore, the characteristic ports of the fourth to sixth embodiments are as shown in FIG.
Due to the positional relationship between 18 and the insulating cylinder 2a, the characteristic ports correspond to the characteristic rows B, A and C, respectively, and the cooling effect is almost the same.

In each of the above embodiments, the guide pin 8 is attached to the fixed-side mounting conductor 3 and the guide portion 9 is attached to the movable-side mounting conductor 6, but may be reversed. Further, although the movable lead 12 is integrated with the guide section 9, it may be formed separately. Further, although the upper end of the bellows 16 is attached to the movable lead 12, it may be attached to the movable attachment conductor 6. Further, the movable lead 12 and the movable lead bolt 11 may be integrated.

FIG. 9 is a plan view of the vacuum capacitor shown in the reference example. A water-cooling pipe 19 is hermetically attached to the outer surface of the fixed-side mounting conductor 3. The water-cooling pipe 19 has an inlet 19a and an outlet 19b. Having. And the input port 19
The vacuum condenser is cooled by flowing cooling water from a and flowing out from the outlet 19b.
Since the contact area between the water cooling pipe 19 and the fixed-side mounting conductor 3 is small, and no water pool is formed in the water cooling pipe 19, the cooling effect is small, and the characteristics are as shown in FIG. Since this is not much different from D, the effect as the invention cannot be obtained.

[0026]

As described above, according to the first aspect of the present invention, a hollow water-cooled flange is provided in close contact with the outer surface of the fixed-side mounting conductor, and cooling water flows through the water-cooled flange. The surface temperature of the capacitor decreases, and the heat resistance of the connection conductor and the supporting insulator can be reduced. In addition, the bellows is indirectly cooled due to the decrease in the surface temperature of the vacuum capacitor, and the dielectric loss due to the increase in resistance is reduced, so that a capacitor with good performance can be obtained. Further, the current flowing through the vacuum capacitor can be increased, and the diameter of the bellows does not need to be increased, and the rotational torque of the adjusting nut can be reduced.

According to the second aspect, a water-cooled flange is attached to the outer surface of the movable-side current collector, and has the same effect as the first aspect.

According to the third aspect, since the water cooling flanges are provided on the fixed side and the movable side, the cooling effect can be enhanced, and the above-mentioned effect can be enhanced.

According to claim 4, the water-cooled flange is formed of any one of copper, silver and aluminum.
Since these have high thermal conductivity, the effect can be further enhanced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a vacuum capacitor according to Embodiment 1 of the present invention.

FIG. 2 is a diagram showing surface temperature-current flow characteristics of a vacuum capacitor according to Embodiments 1 to 3 of the present invention.

FIG. 3 is a vertical sectional view and a bottom view of a vacuum capacitor according to a second embodiment.

FIG. 4 is a longitudinal sectional view of a vacuum capacitor according to a third embodiment.

FIG. 5 is a vertical sectional view of a vacuum capacitor according to a fourth embodiment.

FIG. 6 is a vertical sectional view of a vacuum capacitor according to a fifth embodiment.

FIG. 7 is a vertical sectional view of a vacuum capacitor according to a sixth embodiment.

FIG. 8 is a graph showing surface temperature-current flow characteristics of vacuum capacitors according to Embodiments 4 to 6.

FIG. 9 is a plan view of a vacuum capacitor according to a reference example.

FIG. 10 is a graph showing surface temperature-current flow characteristics of a vacuum capacitor according to a reference example.

FIG. 11 is a longitudinal sectional view of a conventional vacuum capacitor.

FIG. 12 is a partially enlarged view of FIG. 11;

FIG. 13 is a graph showing surface temperature-current flow characteristics of a conventional vacuum capacitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Vacuum container 2 ... Cylindrical part 2a ... Insulating cylinder 3 ... Fixed side mounting conductor 4 ... Movable side current collector 4a ... Insertion hole 5 ... Fixed electrode 6 ... Movable side mounting conductor 7 ... Movable electrode 10 ... Screw receiving part 11 ... Movable lead bolt 12: Movable lead 13: Adjusting nut 16: Bellows 17, 18: Water-cooled flange.

Claims (4)

[Claims] 1. A vacuum vessel whose inside is evacuated by providing a fixed-side mounting conductor at one end of a cylindrical portion having an insulating portion, a movable-side current collector at the other end of the cylindrical portion, and a fixed-side mounting conductor. A fixed electrode formed by attaching a plurality of concentric cylindrical electrode plates having different diameters inside a plurality of cylindrical electrodes having different diameters so that the fixed electrode can be inserted and removed without contact between the respective cylindrical electrode plates. A movable electrode formed by concentrically attaching the electrode plate to the movable-side mounting conductor, a screw receiving portion provided in an insertion hole provided in the center of the movable-side current collector, and a movable lead on the movable-side mounting conductor. A movable lead bolt inserted into the screw receiving portion and screwed with the movable lead bolt are locked together with the screw receiving portion,
An adjustment nut that moves the movable electrode with respect to the fixed electrode by rotation, and is located on the outer peripheral side of the movable lead bolt. One end is attached to the movable current collector, and the other end is attached to the movable attachment conductor or the movable lead. A vacuum condenser provided with a cylindrical bellows, wherein a hollow water-cooling flange is provided in close contact with the outer surface of the fixed-side mounting conductor, and cooling water flows through the water-cooling flange. Capacitors. 2. A vacuum container whose inside is evacuated by providing a fixed-side mounting conductor at one end of a cylindrical portion having an insulating portion, a movable-side current collector at the other end of the cylindrical portion, and a fixed-side mounting conductor. A fixed electrode formed by attaching a plurality of concentric cylindrical electrode plates having different diameters inside a plurality of cylindrical electrodes having different diameters so that the fixed electrode can be inserted into and removed from each cylindrical electrode plate in a non-contact manner. A movable electrode formed by concentrically attaching the electrode plate to the movable-side mounting conductor, a screw receiving portion provided in an insertion hole provided in the center of the movable-side current collector, and a movable lead on the movable-side mounting conductor. A movable lead bolt inserted into the screw receiving portion and screwed with the movable lead bolt are locked together with the screw receiving portion,
An adjusting nut that moves the movable electrode with respect to the fixed electrode by rotation; and an outer circumferential side of the movable lead bolt, one end of which is attached to the movable-side current collector, and the other end of which is the movable-side mounting conductor or the movable lead. In a vacuum capacitor having a cylindrical bellows attached to a movable current collector, a hollow water-cooled flange is provided in close contact with the outer surface side of the movable current collector, and cooling water flows through the water-cooled flange. And a vacuum condenser. 3. A vacuum container whose inside is evacuated by providing a fixed-side mounting conductor at one end of a cylindrical portion having an insulating portion, a movable-side current collector at the other end of the cylindrical portion, and a fixed-side mounting conductor. A fixed electrode formed by attaching a plurality of concentric cylindrical electrode plates having different diameters inside a plurality of cylindrical electrodes having different diameters so that the fixed electrode can be inserted into and removed from each cylindrical electrode plate in a non-contact manner. A movable electrode formed by concentrically attaching the electrode plate to the movable-side mounting conductor, a screw receiving portion provided in an insertion hole provided in the center of the movable-side current collector, and a movable lead on the movable-side mounting conductor. A movable lead bolt inserted into the screw receiving portion and screwed with the movable lead bolt are locked together with the screw receiving portion,
An adjustment nut that moves the movable electrode with respect to the fixed electrode by rotation, and is located on the outer peripheral side of the movable lead bolt. One end is attached to the movable current collector, and the other end is attached to the movable attachment conductor or the movable lead. In the vacuum condenser provided with the cylindrical bellows, a hollow water-cooling flange is provided in close contact with the outer surface of the fixed-side mounting conductor and the outer surface of the movable-side current collector, and cooling water flows through the water-cooling flange. A vacuum capacitor characterized in that: 4. The water cooling flange according to claim 1, wherein said water cooling flange is made of any one of copper, silver and aluminum.
3. The vacuum capacitor according to any one of items 1 to 3,