JPH08111150A - Vacuum circuit breaker - Google Patents

Abstract

PURPOSE: To improve withstand voltage characteristics, and downsize an external shape. CONSTITUTION: A conductor support part 10 is suspended from an upper end plate 4A of an insulating cylinder 1, and an upper conductor 3 of a vacuum valve 1 is supported with an under surface of this conductor support part 10. A truncated cone shaped boss part 11A is protrusively arranged in an upper part on an outside surface of the insulating cylinder 1, and a boss part 11B is similarly protrusively arranged in a lower part. An upper polar terminal 3a is penetratingly arranged on the axis of the boss part 11A, and the base end of this upper polar terminal 3a is brazed to a side surface of the upper conductor 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum circuit breaker housed in a metal-closed switchgear or the like installed for power receiving and transforming equipment.

[0002]

2. Description of the Related Art FIG. 5 is a front view showing a state in which a conventional vacuum circuit breaker is housed inside a box of a metal-closed switchgear. In FIG. 5, a box body whose outer periphery is hermetically welded
Inside the 13B, three insulating cylinders 1 will be described in detail later with reference to FIG.
A is adjacent to each other on the left and right, and the upper end of each insulating cylinder 1A is fixed to the upper end plate 4B. An operation unit 6 is attached to the lower end of each insulating cylinder 1A via a plurality of support members 7. Sulfur hexafluoride gas 14 is sealed inside the box 13B at a pressure of about 100,000 pascals, and a gap G2 between the insulating cylinders 1A and a ground potential G1 between the box 13B and the like. The withstand voltage characteristic of the part is maintained.

FIG. 6 is a vertical cross-sectional view showing the insulating cylinder 1A shown in FIG. 5 and a vacuum valve housed inside the insulating cylinder 1A, showing an open state. In FIG. 6, the upper conductor 3 is fixed to the lower surface of the upper end plate 4B at the upper end of the insulating cylinder 1A cast by epoxy resin, and the lower end plate 5 made of an insulator is attached to the lower end of the insulating cylinder 1A. Are integrally formed. Of these, the vacuum valve 2 described below is vertically fixed to the lower surface of the upper conductor 3 via an upper end plate 24 at the upper end.

In the vacuum valve 2, the upper end of an insulating container 23 is fixed to the lower surface of the upper end plate 24 in a cylindrical shape by brazing, and the lower end plate 25 is symmetrically brazed to the lower end of the insulating container 23. Has been done. Of these, the upper end of a fixed rod 26 made of a copper rod is brazed to the center of the lower surface of the upper end plate 24, and the lower end of the fixed rod 26 has the center of the fixed electrode 21 not shown in detail. Abutted and brazed.

A cylindrical stainless steel plate shield 30 is coaxially loosely fitted inside the insulating container 23, and the central portion of the outer surface is fixed to the inner surface of the insulating container 23. A through hole is formed in the center of the lower end plate 25, and the lower end of a bellows 28 formed in a tubular shape from a stainless steel plate is brazed to the inner surface of the lower end plate 25. The upper end of the bellows 28 is brazed to the lower surface of the upper end of a bellows cover 29 made of a stainless steel plate and formed in a tubular shape having a U-shaped cross section.

A movable rod 27 made of a copper rod extends vertically through the through hole of the lower end plate 25.
It contacts a contact plate (not shown) inserted in a through hole formed in the center of the slide contact plate 14 fixed to the lower surface of the. The movable electrode 22 is brazed to the upper end of the movable rod 27, and the movable electrode 22 is opposed to the fixed electrode 21 described above with a predetermined gap. The right end of the slide contact plate 14 is brazed to the left end of the lower pole terminal 14a.
The letter a penetrates a substantially trapezoidal convex portion provided on the right side of the insulating cylinder 1A. Similarly, the left end of the upper pole terminal 3a is also brazed to the right end of the above-described upper conductor 3.

The lower end of the movable rod 27 is connected to the upper end of the movable rod 8 via an insulating rod 9, and the lower end of the movable rod 8 is vertically arranged with the upper end fixed to the lower portion of the lower end plate 5. It is connected to the inside of the operation mechanism section 6 which is fixed to the lower ends of the plurality of support members 7 and whose details have been omitted.

In the vacuum circuit breaker configured as described above, when a vacuum breaker closing signal is input to an operation unit (not shown) installed in the lower portion of the box body 13B shown in FIG. 5, a closing coil (not shown) is input. Is excited to drive each operation mechanism section 6. Then, the movable rod 8 is driven upward, the movable rod 27 connected via the insulating rod 9 is also driven upward, and the movable electrode 22 fixed to the upper end of the movable rod 27 is moved.
Is pressed by the fixed electrode 21 and the vacuum circuit breaker is turned on.

On the other hand, when an opening signal is input to the operation unit (not shown) installed in the lower portion of the box 13B shown in FIG. 5, the trip coil (not shown) is excited and each operation mechanism unit 6 is driven. Then, each movable rod 8 whose lower end is connected to each operation mechanism portion 6 is driven downward, the movable electrode 22 is opened, and the vacuum circuit breaker is brought into the opened state shown in FIG.

By the way, in the vacuum circuit breaker configured as described above, when installed in a substation or the like, for example, an impulse voltage generated by lightning or the like enters and is applied between each phase and the ground potential. . Therefore, the box 13B shown in FIG.
When assembled in a box, the box 13B is assembled with a predetermined gap so that the withstand voltage value between the box 13B and the ground potential portion or the withstand voltage value between each phase becomes a predetermined value or more, and when shipped from the factory, The test voltage is applied to confirm and guarantee.

On the other hand, in power receiving equipment installed in urban buildings and the like, a switch gear is required to be downsized due to a rising land price. Therefore, a gas insulated switchgear has been developed and downsized for a vacuum circuit breaker. The request of is becoming stronger and stronger.

[0012]

However, in the vacuum circuit breaker configured as described above, the box body 13 shown in FIG.
In order to reduce the frontage width W2 of B, the diameter of the upper end plate 4B fixed to the upper end of each insulating cylinder 1A is reduced, or in FIG.
It is necessary to reduce the gap G1 between the B and the ground potential portion.

However, of these, the former upper end plate 4B
There is a limit to the method of reducing the diameter of the insulating cylinder 1A depending on the diameter of the insulating cylinder 1A, and the diameter of the insulating cylinder 1A is also determined by the outer diameter of the vacuum valve 2 housed inside the insulating cylinder 1A. If the outer diameter of the vacuum valve 2 is reduced, the diameter of the shield 30 must also be reduced. Then, the fixed electrode 21
This method cannot be adopted because the withstand voltage value between the movable electrode 22 and the movable electrode 22 decreases, and the cutoff characteristic also decreases.

On the other hand, in FIG. 5, the method of reducing the gap G2 between the insulating cylinders 1A and the box body 13B also cannot be adopted because it lowers the withstand voltage value between the phases. , G2, a method of inserting an insulating plate is adopted, but the reduction of the frontage width W2 described above by this method has already reached its limit.

Therefore, an object of the present invention is to obtain a vacuum circuit breaker which can be made smaller in outer shape without lowering the withstand voltage characteristic.

[0016]

A vacuum valve according to the present invention is characterized in that a fixed side terminal conductor and a movable side terminal conductor of a vacuum valve housed in an insulating cylinder and fixed to an upper end plate of the insulating cylinder are provided. A vacuum circuit breaker penetrating the insulating cylinder is characterized in that a boss portion, through which the fixed-side terminal conductor penetrates the shaft center, is projectingly provided on the outer surface of the insulating cylinder.

Further, in the vacuum circuit breaker of the invention described in claims 2 and 3, the vacuum circuit breaker in which the vacuum valve fixed to the upper end plate of the insulating cylinder via the fixed-side conductor is housed in the insulating cylinder. In the above, the insulating column for supporting the vacuum valve via the fixed-side conductor is provided between the fixed-side conductor and the upper end plate.

Further, in the vacuum circuit breaker of the invention described in claim 4, the vacuum valve fixed to the upper end plate of the insulating cylinder via the fixed side conductor is housed in the insulating cylinder, and the fixed side terminal conductor of the vacuum valve. In the vacuum circuit breaker in which the movable side terminal conductor and the movable side terminal conductor are provided through the insulating cylinder, an insulating column that supports the vacuum valve via the fixed side conductor is provided between the fixed side conductor and the upper end plate, and the fixed side terminal conductor is located at the axial center. It is characterized in that a penetrating boss portion is projected on the outer surface of the insulating cylinder.

The vacuum circuit breaker according to a fifth aspect of the present invention is characterized in that a conductive coating is formed on the outer surface of the insulating cylinder.

Further, the vacuum circuit breaker of the invention described in claim 6 is characterized in that the upper end plate is made of a metal material.

[0021]

In the vacuum circuit breaker in which a plurality of insulating cylinders accommodating the vacuum valve are incorporated, the creepage distance between the phase and the ground potential portion is extended by the boss portion through which the fixed-side conductor penetrates the shaft center. Withstand voltage characteristics are improved, and also with an insulating column that supports the vacuum valve to the upper end plate via the fixed-side conductor, the increase in creepage distance improves the withstand voltage characteristics between the phase and ground potential. .

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the vacuum circuit breaker of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view showing a vacuum circuit breaker of the present invention, and is a view showing one phase portion corresponding to FIG. 6 shown in the prior art.

In FIG. 1, what is different from FIG. 6 shown in the prior art is the shape of the upper part of the insulating cylinder 1, and the other parts are shown in FIG.
Is the same as Therefore, the same parts as those in FIG.

That is, at the center of the lower surface of the upper end plate 4A of the upper portion of the insulating cylinder 1 cast-molded with glass fiber-containing epoxy resin, a columnar conductor support portion 10 is vertically provided by casting. A buried metal 10a is previously embedded in the lower end of the conductor supporting portion 10.

On the lower surface of the conductor supporting portion 10, the upper conductor 3
Are fixed with bolts. On the outer surface of the upper right side of the insulating cylinder 1, a truncated cone-shaped boss portion 11A is integrally formed by casting,
The upper pole terminal 3a is inserted into the axial center of the boss portion 11A, and the left end of the upper pole terminal 3a is brazed to the right side surface of the upper conductor 3 as in FIG. A boss portion 11B having the same shape as that of the boss portion 11A is projectingly provided on the lower right side of the insulating cylinder 1 as in FIG. 6, and the lower pole terminal 14a is inserted into the shaft center of the boss portion 11B. The left end of 14a is brazed to the right side surface of the lower pole conductor 14.

In the vacuum circuit breaker thus constructed, the upper pole terminal 3a is insulated at its outer periphery by the truncated cone-shaped boss portion 11A. Therefore, when the upper pole terminal 3a is housed in the box body 13A shown in FIG. Even if the gap between the three insulating cylinders 1 adjacent to each other on the left and right is reduced, the creepage distance between the upper pole terminals 3a of each phase becomes longer, so that the withstand voltage characteristic between the phases can be improved.

Similarly, the gap formed between the left and right insulating cylinders 1 and the inner surface of the box body 13A can be reduced by increasing the creepage distance. Therefore, the box body shown in FIG. The front width W1 of the box body 13A can be significantly reduced as compared with the front width W2 of the box body 13B, and the installation floor area of the metal-closed switchgear including the box body 13A and the like can be reduced.

Further, in the vacuum circuit breaker having a low rated voltage, the upper end plate 4A at the upper end of the insulating cylinder 1 can be directly fixed to the metal plate having the ground potential, so that the height of the box 13A can be reduced. .

Furthermore, depending on the rated voltage and the insulation class,
The upper end plate 4A may be a metal plate. In this case, the upper end of the insulating cylinder 1 is an opening, an annular flange is formed on the outer periphery of the opening to fix the metal plate to the flange, and the upper end of the conductor support 10 is also filled with metal. The 10a may be embedded and fixed to the metal plate. Further, the flange portion may be directly fixed to the fixing plate of the box body. In this case, there is also an advantage that the cast molding of the insulating cylinder becomes easy.

Next, FIG. 3A is a partial vertical sectional view showing another embodiment of the vacuum circuit breaker of the present invention, and is a view corresponding to FIG.

In FIG. 3 (a), as the conductor supporting portion 10A, an annular convex portion 10b is formed on the central outer periphery to increase the vertical creeping distance of the conductor supporting portion 10A to improve the withstand voltage characteristic. Is.

In this case, the upper end plate 4A and the upper conductor 3
Since the withstand voltage value between and can be further increased, even if the upper end plate 4A is made of a metal material, there is an advantage that it can be applied to a vacuum circuit breaker having a high rated voltage and a high insulation class.

FIG. 3B shows another embodiment of the vacuum circuit breaker according to the present invention, and is a partial longitudinal sectional view corresponding to FIGS. 1 and 3A. In FIG. 3B, four steps of protrusions 10c are formed on the outer periphery of the conductor support portion 10B, and the upper conductor 3 and the upper end plate 4A are different from those of the vacuum circuit breaker shown in FIG.
The creepage distance between and is further extended. In this case, as compared with the vacuum circuit breaker shown in FIG. 3 (a), it can be applied to a metal-closed switchgear having a higher rated voltage and an insulation class.

FIG. 4 is a view showing still another embodiment of the vacuum circuit breaker according to the present invention, which is a view corresponding to FIGS. 1 and 3. In FIG. 4, a conductive coating film 12 shown by a broken line is formed on the outer surface of the insulating cylinder 1 except for the boss portions 11A and 11B. In this case, the electric field strength on the surface of the coating film when the insulating cylinder 1 is housed inside the box can be reduced.

Therefore, not only can the front width W1 of the box 13A shown in FIG. 2 be further reduced, but also the box 13A
Since it is possible to reduce restrictions on the installation location of the insulating cylinder 1 inside the box, the degree of freedom in arranging other electric devices and connecting conductors inside the box body 13A is increased, and the mounting density of the electric devices is increased. Since the temperature distribution can be leveled, the box 13A can be further downsized, and the insulation can be prevented from deteriorating and the current carrying capacity can be increased.

In the above embodiment, an example in which it is applied to a vacuum circuit breaker has been described. However, as long as the vacuum valve is housed in a cylindrical insulating container, it may be a vacuum open / close container, a vacuum switch, or a vacuum switch. The same can be applied to the contactor.

[0037]

As described above, according to the present invention, a vacuum valve in which a fixed side terminal conductor and a movable side terminal conductor of a vacuum valve which are housed in an insulating tube and fixed to an upper end plate of the insulating tube are provided through the insulating tube. In the circuit breaker, a boss portion through which the fixed-side terminal conductor penetrates the shaft center is provided so as to project on the outer surface of the insulating tube, or an insulating column that supports the vacuum valve is fixed between the fixed-side conductor and the upper end plate. In this case, in a vacuum circuit breaker in which a plurality of insulating cylinders containing a vacuum valve are incorporated, the withstand voltage characteristics between the phase and the part to ground potential are improved by the boss part where the fixed-side conductor penetrates the shaft center. In addition, since the withstand voltage characteristic is also improved by the insulating column that supports the vacuum valve on the upper end plate through the fixed-side conductor, it is possible to obtain a vacuum circuit breaker whose external size can be reduced. .

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view showing an embodiment of a vacuum circuit breaker of the present invention.

FIG. 2 is an explanatory view showing the operation of the vacuum circuit breaker of the present invention.

FIG. 3A is a partial vertical sectional view showing another embodiment of the vacuum circuit breaker of the present invention. FIG. 6B is a partial vertical cross-sectional view showing another embodiment of the vacuum circuit breaker of the present invention.

FIG. 4 is a partial detailed view showing still another embodiment of the vacuum circuit breaker of the present invention.

FIG. 5 is a front view showing an example of a conventional vacuum circuit breaker.

FIG. 6 is a partial vertical sectional view showing an example of a conventional vacuum circuit breaker.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Insulating cylinder, 2 ... Vacuum valve, 3 ... Upper conductor, 3a ... Upper pole terminal, 4A, 24 ... Upper end plate, 5 ... Lower end plate, 6 ... Operation mechanism part, 7 ... Support member, 8, 27 ... Movable rod, 9 ... Insulating rod, 10, 10A, 10B ... Conductor supporting portion, 11A, 11B ... Boss portion, 12 ... Conductive coating, 13A ... Box body, 14 ... Slide contact plate, 21 ... Fixed electrode, 22 ... Movable rod Electrodes, 23 ... Insulating container, 25 ... Lower end plate, 26 ... Fixed rod, 28 ... Bellows, 29
… Bellows cover, 30… shield.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Shioiri No. 1 Toshiba-cho, Fuchu-shi, Tokyo Toshiba Corporation Fuchu factory inside

Claims (6)

[Claims] 1. A vacuum circuit breaker in which a fixed-side terminal conductor and a movable-side terminal conductor of a vacuum valve housed in an insulating cylinder and fixed to an upper end plate of the insulating cylinder are provided through the insulating cylinder. A vacuum valve, characterized in that a boss portion through which the terminal conductor penetrates the axis is provided so as to project on the outer surface of the insulating cylinder. 2. A vacuum circuit breaker in which a vacuum valve fixed to an upper end plate of an insulating cylinder via a fixed-side conductor is housed in the insulating cylinder, and an insulation supporting the vacuum valve via the fixed-side conductor. A vacuum circuit breaker, wherein a column is provided between the fixed-side conductor and the upper end plate. 3. The vacuum circuit breaker according to claim 2, wherein an annular convex portion is formed on the outer circumference of the insulating column. 4. A vacuum valve fixed to an upper end plate of an insulating cylinder via a fixed conductor is housed in the insulating cylinder, and a fixed side terminal conductor and a movable side terminal conductor of the vacuum valve penetrate the insulating cylinder. In the provided vacuum circuit breaker, an insulating column that supports the vacuum valve via the fixed-side conductor is provided between the fixed-side conductor and the upper end plate, and a boss portion through which the fixed-side terminal conductor penetrates the axial center is provided. A vacuum circuit breaker characterized by being provided on the outer surface of the insulating cylinder. 5. The vacuum circuit breaker according to claim 1, wherein a conductive ground film is formed on the outer surface of the insulating cylinder. 6. The vacuum circuit breaker according to claim 1, 2, 3, 4, or 5, wherein the upper end plate is made of a metal material.