JPS6216485B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a switch used in a high-power circuit, and in particular to a type of switch that sucks in an arc and extinguishes it by utilizing the negative pressure that occurs when a contactor opens and closes. This relates to switches.

As this type of switch, the present inventor has proposed the switches shown in FIGS. 1 to 3.

That is, 1 is a terminal plate that is fixedly held on a fixed part (not shown), and 2 is a fixed outer cylinder with one end closed, that is, one end is fixed to, for example, the terminal plate 1 and is closed. An insulating nozzle 2b is provided at the other end of the fixed outer cylinder 2, and a cylinder 3 forming a suction chamber 9, which will be described later, is connected to the outer periphery of the end where the insulating nozzle 2b is located. . Reference numeral 4 designates a first contact that is fixed to the terminal plate 1 and is located within the fixed outer cylinder, and reference numeral 5 designates a first contact whose tip end slidably passes through the center hole of the insulating nozzle 2b, and which is connected to a drive mechanism (not shown). ) is driven by the fixed outer cylinder 2
It is a shaft-shaped second contact that can go in and out and come into contact with and separate from the first contact 4, and the rear end of the second contact 5 can slide freely through the through hole 6a of the terminal plate 6. penetrate,
It comes into sliding contact with a current collector 6b fixed to the terminal plate 6, and is configured to be energized via this.
When the first and second contacts 4 and 5 are in closed contact, the first and second contacts 4 and 5, which are in closed contact with the terminal plate 1 and fixed outer cylinder 2, are fixed by the insulating nozzle 2b. A gas storage chamber 7 is formed in the outer cylinder 2, and a cylinder is formed by the shaft-shaped second contact 5, the piston 8 fixed thereto, the end face of the fixed outer cylinder 2, and the insulating nozzle following this end face. A suction chamber 9 is formed within 3.

And the entire part of the above structure is a container (not shown) filled with sulfur hexafluoride (SF ₆ ) gas.
The switch is constructed by being stored in the switch.

As shown in FIG. 1, the switch constructed as described above is comprised of first and second contacts 4 and 5 in a closed state. Terminal board 1 - first contact 4 - second contact 5 - current collector 6b
- In order to interrupt the electrical circuit of the terminal board 6, the second contact 5 is moved in the direction of arrow A by a drive mechanism (not shown).
When driven in the direction, an arc 10 is generated between the first contact 4 and the end face of the shaft-shaped second contact 5, as shown in FIG. As a result, the piston 8 moves, the volume of the suction chamber 9 increases, and negative pressure is generated.The gas in the storage chamber 7 is heated by the generation of an arc, and its pressure increases, and the second contact 5 When the tip of the nozzle 2b passes through the center hole of the nozzle 2b, the gas in the storage chamber 7 passes through the suction guide formed by the center hole of the nozzle 2b and the tip of the second contact 5, and is generated in the suction chamber 9. The arc 10 is sucked in by negative pressure and exhausted into the suction chamber 9, and is cooled and extinguished by blowing gas through the suction guide. This state of completion of arc interruption is shown in FIG.

However, in the case of the switch having the above configuration, when the current to be interrupted is large and the generated arc energy is large, the negative pressure in the suction chamber is not sufficient to blow the air, and a large amount of energy is lost even at the current zero point. It remains in the storage chamber 7 and cannot be shut off. Therefore, with the conventional configuration described above, it is not possible to interrupt a large amount of current, and even after the current is interrupted, high-temperature gas remains in the storage chamber and suction chamber, so the voltage subsequently applied between both contacts is This has the disadvantage that the insulation between the arc contacts that have been separated due to this is destroyed, and current flows through the electrical circuit again.

This invention was made in order to eliminate the drawbacks of the switch having the above-mentioned configuration, and in particular, by communicating the suction chamber with the outside air during the opening operation of both the contacts, the discharge of arc energy is achieved. The object of the present invention is to provide a switch which can smoothly cut off a larger current than the above-described switch and which is free from the risk of dielectric breakdown after the contacts are opened.

Hereinafter, this invention will be specifically explained based on drawings showing examples thereof.

What is shown in FIG. 4 to FIG.
Parts that are the same or similar to those shown in the figures are labeled with the same numbers.

That is, 1 is a terminal plate, 2 is a fixed outer cylinder, 3 is a cylinder, 4 is a first contact, 5 is a second contact, 6 is a terminal plate, 7 is a storage chamber, 8 is a piston, 9 is a suction chamber, 2b is an insulated nozzle, 6b is a current collector,
In this invention, a vent hole 11 communicating with the suction chamber 9 is formed in the cylinder 3. The vent hole 11 is formed so that it is passed by the piston 8 when the tip of the second contact 5 moving together with the piston 8 finishes passing through the insulating nozzle during the stroke of the piston 8 moving inside the cylinder 3. When the piston 8 is positioned and the piston 8 passes through the vent hole 11, the suction chamber 9 is communicated with the outside air through the vent hole 11.

In the switch configured as described above, as shown in FIG. 4, the second contact 5
When the is moved in the direction of arrow B in the drawing, an arc 10 is generated between the first contact 4 and the end face of the shaft-shaped second contact 5, as shown in FIG. The piston 8 is moved by the drive of the child 5, and the volume of the suction chamber 9 is increased to generate negative pressure, and the gas in the storage chamber 7 is heated by the arc generation, and its pressure is increased. When the tip of the second contact 5 passes through the insulating nozzle 2b, the gas in the storage chamber 7 passes through the suction guide section formed between the insulating nozzle 2b and the tip of the second contact 5, and passes through the suction chamber 9. Since the current flows out and cools the arc 10 on the way, in the case of a small current, the interrupted arc is quickly extinguished at the current zero point.

However, in the case of a large current that is not interrupted by the above-mentioned arc-extinguishing operation, the gas in the storage chamber 7 has a higher pressure than the outside air due to the heat effect of the arc, so the piston 8 moving together with the second contact 5 As shown in FIG. 6, when the suction chamber 9 communicates with the outside air through the ventilation hole 11 after passing through the position of the ventilation hole 11, the gas passes through the ventilation hole 11 as shown by arrow C toward the outside air. leak. On the way, the arc 10 is cooled and extinguished by the gas blown onto it, so that the current is suddenly cut off. Even after these series of shrunken operations are completed, the high-temperature gas remaining in the storage chamber 7 and suction chamber 9 continues to be exhausted through the ventilation hole 11, as shown in FIG. The voltage strength between the first and second contacts 4 and 5 is increased, and strong resistance to applied voltage is maintained.

In the above embodiment, after the tip of the second contact 5 passes through the insulating nozzle 2b, the suction guide formed at the tip of the second contact 5 opens the storage chamber 7.
As shown in FIG. 8, a communication hole 12 is provided in the first contact 5, and when this hole passes through the nozzle 2b, the communication hole 12 communicates with the suction chamber 9. An embodiment in which the storage chamber 7 and the suction chamber 9 are communicated with each other through the formed suction guide section is also possible.

As described above, according to the present invention, the cold gas storage chamber is communicated with the outside air through the ventilation hole 11 during the opening operation of the contact, and the arc energy is discharged to the outside air through the communication hole. This structure has the advantage of providing a switch with strong dielectric strength for interrupting large-capacity currents.

[Brief explanation of the drawing]

Figures 1 to 3 are cross-sectional views of a switch shown as a reference example, with Figure 1 showing the closed state and the second
The figure shows the switch in progress, FIG. 3 shows the switch in the completed state, and FIGS. , FIG. 5 and FIG. 6 are diagrams showing the shutoff operation in progress, FIG. 7 is a diagram showing the shutoff completed state, and FIG. 8 is a sectional view similar to FIG. 4 showing another embodiment. DESCRIPTION OF SYMBOLS 1... Terminal board, 2... Fixed outer cylinder, 2b... Insulating nozzle, 3... Cylinder, 4... First contact, 5... Second contact, 6... Terminal plate, 6a... Through hole, 6b... Current collector, 7 ...Storage chamber, 8...Piston, 9...Suction chamber, 1
0...Arc, 11...Vent hole, 12...Communication hole.

Claims (1)

[Scope of Claims] 1. A fixed outer cylinder with one end closed, an insulating nozzle fixed to the other end of the fixed outer cylinder, and a first contact disposed inside the fixed outer cylinder and fixed to the one end. With a child
a second contact whose tip part penetrates the center hole of the insulating nozzle and can enter and exit the fixed outer cylinder and can come into contact with and separate from the first contact; and the second contact is connected to the outer periphery of the other end of the fixed outer cylinder. and a piston that is fixed to the second contact in the cylinder and slides in the cylinder in conjunction with the second contact, and the first and second contacts are in closed contact. When the insulating nozzle and the tip of the second contact penetrating through the insulating nozzle form a fluid storage chamber within the fixed cylinder, the piston, the other end surface of the fixed outer cylinder, and the insulating nozzle A suction chamber that generates negative pressure is formed in the cylinder by the opening operation of the second contact, and the opening operation of the second contact by a predetermined distance causes the insulating nozzle and the In a switch in which a suction guide section that communicates the storage chamber and the suction chamber is formed by the tip of the second contact, the distance is sufficient for the tip of the second contact to form the suction guide. A switch characterized in that the cylinder is provided with a vent hole which is positioned so as to be passed by the piston when the opening operation is performed, and which communicates the suction chamber with outside air. 2. The switch according to claim 1, wherein the suction guide portion is formed between the insulating nozzle and the tip of the second contact. 3. The switch according to claim 1, wherein the suction guide portion is formed by a communication hole provided at the tip of the second contact.