JPS5933725A - Switch - 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] [Technology of the Invention] The present invention utilizes the arc heat generated between the electrodes when a pair of contactors that can be freely approached and separated is opened to increase the pressure of the arc-extinguishing fluid.
This invention relates to a so-called self-blade arc-extinguishing switch that extinguishes an arc by spraying it onto the arc. .

[Technical background of the invention and its problems]

Conventionally, this type of switch is generally shown in FIG. In addition, in FIG. 1, the left hand half shows the closed state, and the right half shows the open state. That is, when the movable contact 1 is lowered by a drive device (not shown), the poles open, an arc 3 is generated between the movable contact 1 and the fixed contact 2, and the external pressure chamber 4 is extinguished by this arc heat. The arc fluid is heated and pressurized,
It flows into the arc extinguishing chamber 6 through the flow path 5.

At this time, the passage 7 is closed by the movable contact 1 and the closing valve 8, so the pressure in the arc extinguishing chamber 6 increases.

When the opening progresses further and the blocked state of the passage 7 is released, the high-pressure arc extinguishing fluid in the arc extinguishing chamber 6 moves as shown by the arrow and is sprayed onto the arc 3, extinguishing the arc 3. ing.

By the way, in conventional self-blade arc-extinguishing type switches, the same boosting chamber 4 and arc-extinguishing chamber 6 are used for both large-current shear breaker and small-current breaker. It is impossible to obtain adequate arc extinguishing fluid flow and pressure.

In other words, when trying to increase the breaking current, the volume of the booster chamber 4 and the arc extinguishing chamber 6 must be increased to ensure the flow rate of the arc extinguishing fluid, but the arc energy is insufficient for small currents. , the external pressure of the large amount of arc-extinguishing fluid filled in the external pressure chamber 4 becomes insufficient, resulting in inconvenience in interrupting small currents.

[Purpose of the invention]

The present invention has been made based on the above circumstances, and its object is to provide a safety switch that can supply an appropriate flow rate and pressure of arc-extinguishing fluid depending on the magnitude of the interrupted current. There is a particular thing.

[Summary of the invention]

The present invention surrounds a pair of contacts that can be freely approached and separated from each other in a fixed chamber filled with an arc-extinguishing fluid, and the opposing electrodes of the pair of contacts, and an arc generated between the contacts when the contacts are opened. A pressurizing chamber is provided, which stores arc extinguishing fluid pressurized by the arc extinguishing fluid and sprays the arc extinguishing fluid onto the arc, and a cylinder chamber adjacent to this external pressure chamber, which is elastically held by a spring. The present invention is characterized in that a piston is provided to partition the external pressure chamber and the cylinder chamber, and the piston is operated by a pressure difference between the pressure of the external pressure chamber and the pressure of the cylinder.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3. In addition, the left half of Figure 2 shows the closed state,
The right half shows the state immediately after opening. Further, the right half of FIG. 3 shows the state before the end of the opening, and the left half shows the state after the end of the opening. That is, 11 in the figure is an arc extinguishing fluid (
For example, a fixed chamber filled with 8Fg gas, etc.), this fixed chamber 11 surrounds a pair of fixed contacts 12 and a movable contact 13 that can be freely approached and separated, and between the opposing electrodes of these contacts 12.13, An external pressure chamber 15 that stores an arc-extinguishing fluid whose pressure is increased by the arc heat of the arc 14 generated between the contacts 12 and 13 when the contacts are opened, and a cylinder chamber 1 adjacent to this pressurization chamber 15.
6 is provided. The external pressure chamber 15 is an insulated nozzle 1
7, the movable contact 13, and a piston 18, which will be described later, are closed when the movable contact 13 is closed, and are opened when the movable contact 13 is opened, so that the arc extinguishing fluid inside is blown to the arc 14. The arc 14 is extinguished. The cylinder chamber 16 is provided with a piston 18 that is elastically held by a spring 19 and partitions the pressurization chamber 15 and the cylinder chamber 16. It operates based on a pressure difference. Further, this piston 18 is provided with a check valve 20 so that when the piston 18 moves upward and the pressure in the cylinder chamber 16 increases, the pressure is released into the pressure increasing chamber 15 so that the operation of the piston 1B can be easily performed. It has become. Further, when the piston 18 returns and the pressure in the cylinder chamber 16 decreases, the reverse valve 2 operates to introduce external arc extinguishing fluid.

Next, the operation of the above configuration will be explained. Note that the arrows in FIGS. 2 and 3 indicate the flow of arc-extinguishing fluid. That is,
After the movable contact 13 begins to descend by an operation mechanism (not shown) and moves in a wiping dimension with respect to the fixed contact 12, the fixed contact 12 and the movable contact 13 are separated, and an arc 14 is generated during this time. This arc 14 boosts the pressure of the fluid filled in the pressurization chamber 15, and when the arc energy of the insulation nozzle 17 decreases near the current zero point, the arc 14
4 to extinguish the arc.

In the case of small current cutoff, the volume of the pressurizing chamber 15 is reduced to the piston 18.
Since the structure is such that the pressure is appropriately small, the pressure rises quickly, and it is possible to achieve a pressure sufficient to extinguish the arc even with a small thermal energy of a small current. When the breaking current is large and the arc energy of the arc 14 is large, the heated and pressurized arc extinguishing fluid in the booster chamber 15 overcomes the spring pressure of the spring 19 and pushes the piston 18 upwards, increasing the volume of the booster chamber 15. 6 In addition, a large amount of high-pressure arc extinguishing fluid is stored, and when it is sprayed onto the arc 14 near the current zero point, the arc 14 is extinguished. Since the pressure of can.

Although the fixed electrode is shown as hollow in this embodiment, the end portion thereof is closed with a lid 22. In order to prevent an excessive rise in pressure when a large current is applied, it is effective to provide a pressure relief valve here, or to leave the end completely open.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to supply arc-extinguishing fluid at an appropriate pressure and flow rate depending on the magnitude of the interrupted current, so it is possible to safely interrupt the arc without causing any new phenomena, and it is simple and compact. It is possible to provide a self-blade arc-extinguishing switch with excellent structure and practicality. .

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional self-blade arc-extinguishing switch, and FIGS. 2 and 3 are sectional views showing a self-blade arc-extinguishing switch according to the present invention. 11...Fixed chamber, 12...Fixed contact, 13...
Movable contactor, 14... Arc, 15... Pressure boosting chamber, 1
6... Cylinder chamber, 18... Piston, 19...
·Spring. Applicant's representative Patent attorney Takeshi Suzue Syllable 1 Figure 2

Claims (1)

[Claims] A fixed chamber filled with arc-extinguishing fluid surrounds a pair of contacts that can be freely moved toward and away from them and the opposing electrodes of this pair of contacts, and when the contacts are opened, an external pressure is generated by the arc generated between the contacts. A pressure boosting chamber is provided which houses arc extinguishing fluid and sprays the arc extinguishing fluid onto the arc, and a cylinder block adjacent to this external pressure chamber, the cylinder chamber is elastically held by a spring and is 1. A switch comprising: a piston that partitions a pressure increase chamber and a cylinder chamber; and the piston is configured to be operated by a pressure difference between the pressure of the external pressure chamber and the pressure of a spring.