JPH029410B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field This invention relates to an electrode structure for a switch.

BACKGROUND OF THE INVENTION It has been proposed to provide a shield electrode around a fixed electrode in order to improve potential concentration between the fixed electrode and the ground in a switch or the like (Japanese Patent Application Laid-Open No. 139072/1983).

Problems to be Solved by the Invention However, in the case of the above-mentioned shield structure, the technique aims at alleviating the electric field between the fixed electrode and the ground and improving the potential concentration between the fixed electrode and the ground. Because there is no countermeasure against potential concentration between the electrode and the movable electrode,
When the circuit is opened, it is necessary to increase the distance between the poles of the same phase, which increases the size of the entire switch.

Purpose The purpose of the present invention is to reduce potential concentration between a fixed electrode and a movable electrode that can connect and separate in the same phase,
Another object of the present invention is to provide an electrode structure for a switch that has a high shielding effect between the ground and contributes to miniaturization of the switch.

Means for Solving the Problems This invention arranges a pair of male fixed electrodes facing each other, so that one of the fixed electrodes can be opened and closed so as to be able to come into contact with and be separated from the other, and can come into sliding contact with the other fixed electrode. A female movable electrode is provided, and a cylindrical electrode support fitting is provided to cover the outer periphery of the distal end of the movable electrode and to drive the movable electrode in an open/close circuit. A bowl-shaped first shield fitting with a radius is arranged, and the electrode support fitting is electrically connected to the movable electrode in order to double as a second shield fitting, and is connected to the first shield fitting when the circuit is closed. The gist is that the third shield fitting is formed to be loosely insertable, and that a third shield fitting in the shape of a cylinder with a bottom is arranged so as to cover the base end of the other fixed electrode, and a radius is formed on the outer peripheral edge of the base end. It is something.

Function: Therefore, unlike the conventional technology, the shield metal fittings provided around the fixed electrode and the movable electrode improve the potential concentration in each of the electrodes, and the distance between the in-phase poles when the circuit is closed can be shortened.

In addition, the shield electrode provided on the movable electrode can be loosely inserted into the shield fitting on the fixed electrode side when closing the circuit, so even though it is placed on the outer periphery of the movable electrode, it will not interfere with the circuit closing operation of the movable electrode. do not have.

Furthermore, since both electrodes have a high shielding effect even between the ground, there is no problem even if the power supply side and load side of the fixed electrode are changed. When the circuit is open, the base end outer peripheral edges of the first and third shield fittings are rounded and no protrusion is formed on the outer surface of the electrode portion, so there is no potential concentration point between the ground and the ground.

Embodiment An embodiment embodying the present invention will be described below with reference to FIGS. 1 to 5. 1 shows the entire gas-filled switch, 2 is a rectangular parallelepiped switch body case made of stainless steel, and 3 and 4 are capacitor bushings on the power supply side and load side, which are opposite to each other on both sides of the main body case 2. Three pairs are arranged horizontally. 5 is a flange metal fitting interposed between the capacitor bushings 3, 4 and the mounting seat 6 described later,
A tube portion 5a is formed in the center thereof, through which the capacitor cores 3b and 4b are inserted and supported.

Reference numeral 6 denotes a mounting seat for mounting the capacitor bushings 3 and 4 to the main body case, which is also made of stainless steel and is formed into a nearly cylindrical shape with a lid, and the pipe of the flange fitting 5 is mounted in the center of the mounting surface. A through hole 7 is bored through which the portion 5a is inserted. As shown in FIG. 1, three mounting seats 6 are welded to each side of the main body case 2 at the outer periphery of the base end, and the capacitor bushings 3 and 4 are inserted into the through holes 7 of the mounting seats 6. The flange fittings 5 are fitted, and in this state, the mounting flanges 3a, 4a of the capacitor bushings 3, 4 are connected to the flange fittings 5, and the mounting flanges 3a, 4a and the mounting seats 6 are connected with eight bolts, respectively.

The inner edge of the mounting seat 6 has a flange 6a curved outward as shown in FIG.
is formed by bending. Reference numeral 9 denotes a reinforcing member consisting of a reinforcing rod or a reinforcing plate installed between adjacent mounting seats 6, and is fixed to the outer periphery of the tip of the mounting seats 6 by welding.

Reference numeral 10 denotes a rod-shaped male fixed electrode that is connected to a conductive member (not shown) in the power supply side bushing 3 and protrudes inward from the inner end of the bushing 3, and has a guide hole 11 in the axial direction at its tip. At the same time, a through hole 12 communicating with the outside is formed on the outer periphery of the fixed electrode 10 corresponding to the bottom of the guide hole 11, and the arc-extinguished exhaust gas introduced into the guide hole 11 is transferred to the fixed electrode 10. I try to expel it to the outside. Note that M1 is an arc-resistant metal provided at the tip of the fixed electrode 10.

Reference numeral 13 denotes a bowl-shaped first shield fitting which is tightened and fixed to the outside of the fixed electrode 10 with a nut 14 so as to cover the exposed portion of the fixed electrode 10, and the tip of the fixed electrode 10 is inserted through the opening 15 at the tip. protrude the part,
It is formed to have a radius at its base end outer peripheral edge. Note that 16 is a tubular buffer seat bolted to the inner bottom of the first shield fitting 13 so as to cover the exposed base end portion of the fixed electrode 10.

Reference numeral 18 denotes a rod-shaped fixed electrode that protrudes inward from the inner end of the capacitor core 4b of the load-side bushing 4 so as to face the fixed electrode 10, and has the same diameter as the fixed electrode 10. Reference numeral 19 denotes a cylindrical support fitting as a third shield fitting which is tightened and fixed to the base end of the fixed electrode 18 with a nut 19a, and a piston ring 2 is attached to the outer periphery of the tip.
0 is fitted, and the distal end surface is covered with an insulating buffer member 21 made of rubber or the like, and the outer peripheral edge of the proximal end is rounded.

Reference numeral 22 shown in FIGS. 1 and 4 is a rotation shaft rotatably supported along the center of both ends of the bottom plate 2a in the main body case 2, and can be externally operated with a handle 50.

Reference numeral 23 denotes a metal swinging arm whose base end is fixed to the rotation shaft 22, and a bifurcated mounting groove 24 into which the rotation shaft 22 is fitted is formed at the base end. The rotation shaft 22 is attached with 25 bolts. The center and tip of the swinging arm 23 are coated with an insulating synthetic resin such as epoxy resin, and an insulating pleat is formed in the center, and a long hole 26 extending in the longitudinal direction is formed in the tip. It is transparent. This swing arm 23 is swingable in the left and right directions as shown in FIGS. 2 and 3 by driving the swing shaft 22 to open and close.

Reference numeral 27 denotes an electrode support fitting as a second shield fitting in the shape of a cylinder with a bottom, which is rotatably attached to the tips of the pair of swinging arms 23. Swing arm 23
A mounting bolt 28 made of an insulating material is loosely inserted into the elongated hole 26. The tip of the electrode support fitting 27 projects slightly further toward the power source side than the movable electrode 39 described later to constitute a shield portion 27a, and can be loosely inserted into the opening 15 of the shield fitting 13.

Note that 28a is a screw screwed into the bottom of the electrode support fitting 27 to prevent the mounting bolt 28 from coming off.

29 is a spacer inserted into the mounting bolt 28 so as to be disposed between the head of the mounting bolt 28 and the electrode support fitting 27;
is slidably engaged with the elongated hole 26 of No. 3, and
The position of the swinging arm 25 is regulated between the stepped portion 29a provided at the end and the head of the mounting bolt 28, so that the swinging arm 23 does not come into contact with the outer periphery of the cylinder 31, which will be described later.

Reference numeral 30 shown in FIG. 5 indicates a plurality of gas passage holes (only one is shown in FIG. 5) which are provided between both side surfaces of the electrode support fitting 27. Reference numeral 31 denotes a cylinder made of an insulating material such as epoxy resin that is fitted around the outer periphery of the electrode support fitting 27, and its base end can slide against the piston ring 20 of the support fitting 19 in an airtight manner. is fitted. cylinder 31
is attached to the electrode support fitting 27 by inserting the proximal end of the spacer 29 inserted into the mounting bolt 28 into a pair of through holes 32 formed at opposite positions at the distal end.

Reference numeral 33 denotes a rod-shaped orifice cone made of an insulating material such as epoxy resin, which is screwed into the inner periphery of the electrode support fitting 27 and fixed with screws 34 so as to maintain airtightness. Same orifice scone 33
The outer periphery of the tip can be loosely inserted into the opening 15 of the first shield fitting 13 as shown in FIG. 10 can be inserted loosely.

Reference numeral 35 shown in FIG. 5 is an electrode mounting portion integrally formed in a cylindrical shape at the center of the bottom of the electrode support fitting 27 so as to extend in the axial direction (in the left-right direction in FIGS. 2 and 3). Reference numeral 36 denotes screw holes passing through the inside and outside at both ends of the electrode mounting portion 35, respectively. As shown in FIG. 5, a plurality of screw holes 36 (six pairs in this embodiment) are provided at predetermined intervals in the circumferential direction, with one set of screw holes 36 corresponding to each other at both ends. There is. Reference numeral 37 denotes a plurality of screws screwed into each screw hole 36 from the outer periphery of the electrode mounting part 35, the tip of which protrudes from the inner periphery of the electrode mounting part 35 and has a reduced diameter cylindrical shape without a thread groove. is formed.

Reference numeral 38 denotes a movable contact member constituting a female movable electrode 39 that can slide back and forth to the left and right along the fixed electrodes 10, 18, and is divided into six equal parts in the circumferential direction. A pair of settling rings 41 are loosely fitted into the engagement groove 40 so as to be able to move toward and away from the fixed electrode 10. The tip of each screw 37 is loosely fitted into a pair of engagement holes 38a provided in the movable contact member 38 corresponding to each set of screw holes 36, and interferes with other adjacent movable contact members 38. In addition, a constant distance is maintained between the fixed electrode 18 and the electrode mounting portion 35 so as not to cause any damage.

Reference numeral 43 denotes a pair of garter springs wound around the distal and proximal ends of each movable contact member 38, which urges each movable contact member 38 inwardly and protrudes from the inner periphery of both ends of the movable contact member 38. The provided contact portions 44 are adapted to contact the outer peripheries of the fixed electrodes 10 and 18, respectively. In addition, the garter spring 43 on the tip side
The outer periphery of is coated with a heat-resistant and arc-resistant insulating material. M2 is an arc-resistant metal fixed to the end of the movable contact member 38 on the side opposite to the fixed electrode 10. The movable contact member 38 and the garter spring 4
3 and settling ring 41 to form a cylindrical movable electrode 3.
9.

In the switch 1 configured as described above, the second
To close the circuit from the open state shown in the figure, the operating handle is operated to move the electrode support fitting 27 in the closing direction (rightward in FIG. 2) via the rotation shaft 22 and the swing arm 23. Then, each movable contact member 38 of the movable electrode 39 is driven and slides along the fixed electrode 18.

After that, the contact portion 4 at the tip of each movable contact member 38
4 and the settling ring 41 are separated from the fixed electrode 18, the tip of the movable electrode 39 is reduced in diameter by the urging force of the garter spring 43 until it is restricted by the settling ring 41. Then, when the contact portion 44 of the movable electrode 39 comes into contact with the fixed electrode 10 on the power supply side, its tip expands in diameter again against the biasing force of the garter spring 41, and each movable electrode 39 moves along the fixed electrode 10. The contact member 38 slides on the contact portion 44 to complete the circuit closure (see FIG. 3).

At this time, the cylinder 31 attached to the electrode support fitting 27 slides to the right with respect to the support fitting 19 via the piston ring 20, and the tip of the orifice cone 33 is loosely inserted into the fixed electrode 10. As shown in FIG. 3, the tip of the electrode support fitting 27 is loosely inserted into the opening 15 of the first shield fitting 13. As shown in FIG. Therefore, even though the electrode support fitting 27 as a second shield fitting is arranged around the movable electrode 39, the electrode support fitting 27
Since it is loosely inserted into the shield fitting 13 on the fixed electrode side without interfering with it, it does not interfere with the circuit closing operation of the movable electrode.

Next, when opening the circuit from the closed state shown in FIG.
(leftward in the figure). Then, the movable electrode 39 separates from the tip of the fixed electrode, and an arc is generated between the arc-proof metal M2 of the movable electrode 39 and the arc-proof metal M1 at the tip of the fixed electrode 10.

On the other hand, as the cylinder 31 moves to the left as the movable electrode 39 moves, the gas inside the chamber surrounded by the cylinder 31 and the support fitting 19 is increased in pressure.
Arc-extinguishing gas is ejected from the gas passage hole 30 of the electrode support fitting 27 toward the inner tip of the orifice cone 33 , and the arc-extinguishing gas is ejected from the gas passage hole 30 of the electrode support fitting 27 toward the inner tip of the orifice cone 33 .
3 and is sprayed onto the arc from the gap formed by the arc. As a result, the arc is stretched inward and finally blown off to extinguish it.

Then, when the contact portion 44 at the tip of the movable electrode 39 contacts the tip of the fixed electrode 18 again, the movable contact members 38 are mutually expanded in diameter and slid onto the outer periphery of the fixed electrode 18, thereby completing the circuit opening. At this time, a sufficient insulation distance after opening is ensured.

In this embodiment, the switch 1 is the main body case 2.
The mounting seat 6 is attached to the mounting seat 6, and the bushings 3 and 4 are fixed through the mounting seat 6, so that a part of the bushings 3 and 4 from the mounting flanges 3a and 4a to the tip on the capacitor core side is attached to the mounting seat. 6. Therefore, the width of the main body case 2 in the mounting direction of the bushings 3 and 4 can be reduced to make the case 2 more compact, and the amount of arc-extinguishing gas sealed inside the main body case 2 can also be reduced. can do.

In this invention, the inner end of the mounting seat 6 protrudes into the main body case 2, and the flange 6a that curves outward is formed on the periphery of the inner end, so that the mounting seat 6
Unlike the case where the inner end of the mounting seat 6 is attached to the main body case 2 so as not to protrude into the main body case 2 or the flange 6a is not formed, there is no risk of potential concentration occurring at the inner end of the mounting seat 6.

Note that the present invention is not limited to the embodiment described above, and for example, when the electrode support fitting 27 as the second shield fitting on the movable electrode 39 side is closed, the external tip of the first shield fitting 13 on the fixed electrode 10 side It may be formed with an enlarged diameter so that it can be loosely inserted over it.

Effects As detailed above, the present invention provides a movable electrode that corresponds to a fixed electrode so as to be able to come into contact with and separate from it, and a bowl-shaped shield fitting is arranged around the outer periphery of the fixed electrode,
By arranging a cylindrical shield fitting on the outer periphery of the movable electrode that is electrically connected to the movable electrode and loosely inserted into the shield fitting when the circuit is closed, potential concentration between the ends of the fixed electrode and the movable electrode can be reduced. This makes it possible to improve the withstand voltage characteristics between both electrodes after an open circuit, and even though the second shield metal fitting is placed around the movable electrode, the second shield metal fitting is on the fixed electrode side. Since it is inserted loosely without interfering with the first shield fitting, it does not interfere with the circuit closing operation of the movable electrode.

In addition, the electric field between the fixed electrode and the movable electrode in the same phase is relaxed by both electrodes, resulting in a high shielding effect, shortening the opening distance when the circuit is opened, and changing the power supply side from the fixed electrode to the movable electrode. In addition, since the first and third shield metal fittings do not form any protrusions between the earth and the earth, potential concentration points between the earth can be eliminated, and the electric field between the earth and the same phase can be relaxed to open and close. This is an excellent invention for industrial use as it allows the vessel itself to be made smaller.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional plan view of a switch showing an embodiment embodying the present invention, FIG. 2 is a cross-sectional view showing the open circuit state of the electrode section, FIG. 3 is a cross-sectional view similarly showing the closed circuit state, and FIG. FIG. 4 is a partial cross-sectional view of the electrode portion seen from the other side showing a closed circuit state as in FIG. 3, and FIG. 5 is a cross-sectional view of the main part of the movable electrode. Switch...1, Main case...2, Power side bushing...3, Load side bushing...4, Mounting seat...6, Flange...6a, Fixed electrode...10,
First shield metal fitting...13, Support metal fitting as third shield metal fitting...19, Electrode support metal fitting as second shield metal fitting...27, Movable electrode...
39.

Claims (1)

[Scope of Claims] 1 A pair of male fixed electrodes 10 and 18 are arranged opposite each other, and one fixed electrode 10 can be opened and closed so as to be able to come into contact with and be separated from the other, and the other fixed electrode 18 can be slid into contact with the other fixed electrode 18. A female movable electrode 39 is provided, and a cylindrical electrode support fitting 27 is provided to cover the outer periphery of the tip of the movable electrode 39 and to drive the movable electrode 39 in an open/close circuit, and is provided on the outer periphery of the one fixed electrode 10. A bowl-shaped first shield fitting 13 with a rounded outer peripheral edge at the base end is arranged, and the electrode support fitting 27 is electrically connected to the movable electrode 39 in order to double as a second shield fitting. A third shield fitting 19 is formed so as to be loosely inserted into the first shield fitting 13 when the circuit is closed, and further a third shield fitting 19 having a bottomed cylindrical shape is arranged so as to cover the base end of the other fixed electrode 18. A switch electrode structure characterized by a rounded edge.