JPS5963624A - Circuit breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Mounan Field) The present invention relates to a circuit breaker that generates an arc in an insulating liquid and extinguishes it when a contact is opened.

[Background technology]

The prior art closest to the present invention already exists in which a liquid is used to extinguish the arc.

In other words, the method is to decompose oil at high temperatures caused by an arc, and use the resulting water-based gas to cool and extinguish the arc.According to this method, the arc current is limited only by cooling the hydrogen gas. Therefore, it is still not satisfactory, and in particular, it has not been possible to respond to the recent increase in the quality of circuit breaker holes, cables, and UJ pipes.

, [Purpose] The present invention has been made in view of the above points, that is, sulfur hexafluoride, chlorofluorocarbon, etc. are vaporized at high temperature in an airtight pressure-resistant outer cylinder, and the temperature is lowered to below a certain temperature. It is filled with an insulating negative liquid that restores its original state.
The purpose is to pressurize the arc with a liquid trowel to increase the arc particle density and increase the arc resistance in a quadratic (nonlinear) manner, thereby increasing the hole diameter and cutting speed.

[Disclosure of the invention]

(Example) The present invention will be described below based on the drawings as an example. Reference numeral 1 denotes an outer cylinder that has airtightness and can withstand high internal pressure, and is mainly made of metal. Reference numerals 2 and 3 denote left and right external terminals installed at both ends of the outer cylinder 1, and contacts 4 and 5, at least one of which is movable, face each other within the outer cylinder 1.
Equipped with Therefore, in the drawings of the embodiment, only the right side is movable, but both the left and right sides may be movable. 6 is a plunger for making this contact 5 movable; 7 is a coil that magnetically drives the plunger 6 with its electromotive flux when a large current such as a short circuit current flows;
wrapped around the outside of the A yoke 8 is formed into a U-shape by an upper piece 9 and left and right pieces 10 and 11, and a plunger 6.
and constitute a magnetic circuit. In addition, in contrast to the U-shaped figure 1,
The coil 7 shown in FIG. 2 is vertically symmetrical, and the coil 7 is wound on the outside of the outer tube 1 in FIG. 1, whereas the coil 7 is wound inside the outer tube 1 in FIG. Either is fine. Therefore, the outer cylinder 1 is further formed of a non-magnetic material.

Also, one end 7a of this coil 7 becomes an input end, and the other end 7a
b is connected to the plunger 6. Reference numeral 12 is an insulating negative (also called electrically negative ion) halogen-based liquid that vaporizes and decomposes at high temperatures, such as sulfur hexafluoride and fluorocarbons, and recovers when the temperature drops below a certain level. Enclosed in 1. This liquid 12 tries to expand in volume due to the generation of an arc when the electrode is opened, but since the volume of the liquid remains unchanged by any phenomenon, it acts to expand the outer cylinder 1 by that amount. However, since the outer cylinder 1 can withstand high pressure sufficiently, the liquid 12 is pressurized, and the arc is pressurized at high pressure, the arc particle density becomes high, and the arc resistance becomes non-linear (quadratic curve-like). The arc increases, the arc disappears, and the interruption is instantaneous.

As a means for enclosing the liquid 12, in the embodiment shown in FIG. 1, screws are formed on the outer peripheral surface of both ends of the outer cylinder 1, and left and right cups 13 and 14, each having a screw formed on the inner peripheral surface, are screwed together to provide insulation. The left and right pieces 10.11 of the U-shaped yoke 8 are connected to the cup 13.14 with a seal 15 interposed therebetween. A fixed iron core 16 is provided on the right bank 11 of the yoke 8 and faces the plunger 6 with a return spring 17 in between. 18 is a flexible lead wire connecting the plunger 6 and the coil 7; 19 is a yoke 81;
This wound secondary coil induces a secondary output when a large current such as a short circuit current flows. A piezoelectric element 20 is activated by the output of the secondary coil 19 and generates ultrasonic vibration between the contacts 4 and 5. Therefore, the vibrations further promote pressurization of the liquids 1 and 2.

In FIG. 2, the element 20 is provided in the outer cylinder 1, but it is provided on the movable contact side.

(Operation) Next, to explain the present invention in detail, FIG. 1 shows both contacts 4 and 5.
This shows the closed state where the two are connected.

When a large current such as a short circuit current flows in the above state, the plunger 5 moves to the right due to the magnetomotive flux of the coil 7, and the contacts 4 and 5 are opened to generate an arc between them.

Due to the generation of this arc, the liquid 12 tends to expand in volume by the volume of the arc, but since the liquid 12 remains unchanged no matter what phenomenon occurs, the outer cylinder 1 is pressurized and the outer cylinder 1 is pressurized. Since tube 1 is pressure resistant, it is pressurized to crush the arc, the density of arc particles increases, the arc resistance rapidly increases in a nonlinear (quadratic) manner, and the arc disappears. , and the shutoff is instantaneous. Further, the piezoelectric element 20 is ultrasonically vibrated by the secondary output of the secondary coil 19 wound around the yoke 8, and the liquid 1
2, and the arc itself is also directly compressed.

Furthermore, at this time, the arc generates high temperature heat, so the liquid 1
2 vaporizes and decomposes, and the arc is cooled by the heat of vaporization, further accelerating the breaking speed.

Of course, when the temperature drops below a certain level after the arc is extinguished, the liquid 12 recovers to its original state and corresponds to subsequent current interruption.

The present invention contains an insulating negative liquid 12, such as sulfur hexafluoride or chlorofluorocarbon, which is vaporized at high temperature and restored when the temperature drops below a certain level, in an airtight pressure-resistant outer cylinder l such as -E or WLl. Since it is sealed, when it is opened, the frk body is pressurized by the volume of the arc, and the outer cylinder 1 cannot withstand the pressure of 11, so the arc is crushed by the liquid 12, and the arc is As the particle density increases, the arc resistance becomes quadratic (
Therefore, compared to the conventional cooling method that relies only on cooling by the heat of vaporization of the liquid, it is better to synergize the additive effect of the liquid as in the present invention. The arc extinguishing time is shorter, and it can handle large currents of 1iJi. Furthermore, the present invention operates the Lff electric element 20 with the output of the secondary coil 19, and the contacts 4,
Since ultrasonic vibrations are applied during the period 5, the ultrasonic vibrations have the effect of promoting compression of the liquid 12 and direct compression of the arc itself, thereby promoting extinguishing of the arc (9.1).

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a cross-sectional front view;
FIG. 2 is a diagram showing an embodiment of the present invention. 1... Outer cylinder, 2, 3... Terminal, 4, 5... Contact,
6... Plunger, 7... Coil, 8... Yoke, 12... Liquid, 19... Secondary coil, 20...
Piezoelectric element. Patent applicant Matsushita Electric Works Co., Ltd. Representative patent attorney Toshimaru Takemoto (and 2 others)

Claims (1)

[Claims] An airtight and pressure-resistant outer cylinder, left and right external terminals located at both ends of this outer cylinder, and two external terminals installed at the tips of the left and right external terminals and facing each other within the outer cylinder. a contact; a plunger in which at least one of the contacts is movable;
When a large current such as a short-circuit current flows, the magnetic flux drives the plunger magnetically to open the contacts, and the coil sealed in the outer cylinder also contains high-temperature materials such as sulfur hexafluoride and fluorocarbons. An insulating negative liquid that vaporizes and decomposes in the air and recovers when the temperature drops below a certain level, a secondary coil installed in the yoke that forms the magnetic path of the coil, and a secondary coil of this coil.
A circuit breaker characterized by comprising an extrusion element that generates high-pressure ultrasonic waves between the contacts at the next output.