JPS6132765B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a switch that extinguishes an arc between contacts by spraying an arc extinguishing fluid onto the arc. The gas opening/closing group will be explained below for convenience.

In conventional devices, such as gas shields and disconnectors, gas at an appropriate pressure is sealed in a container that seals SF ₆ gas, and the pressure difference that generates the gas flow to extinguish the arc is It was created by constantly generating high pressure using a pressure generator. At the time of shedding, the on-off valve between high and low pressures is opened and closed in conjunction with the shearing operation, allowing gas to flow and extinguishing the arc. This method constantly generates high pressure gas,
The structure is very complex due to the separate configuration of the pressure generator and the two pressure systems for high and low pressure, which is large and uneconomical, and it is not practical in terms of maintenance and management to maintain high pressure gas at all times. It had a low flaw.

In addition, in single-pressure puffer type disconnectors, which are the mainstream of current gas shutoff switches, the puffer device is connected to the shutoff operation in a gas space of several atmospheres sealed in a sealed container. This method blows the high pressure obtained by activation onto the arc and breaks it. Compared to the dual pressure type, this system has a relatively low pressure system and seals in compressed gas at several atmospheres, so it has a simple structure and is easy to design for practical use as a pressure vessel.
A mechanical pressure generating device such as a puffer device is required in conjunction with the shedding operation. This puffer device has a large disconnection current, and the driving force increases significantly as the input power increases, so a powerful operating device is required, especially for large-capacity shield disconnectors. Although some of the above compensation means include electromagnetically driven puffer devices, they all have the drawbacks of being large, complex, and uneconomical, and having low practical performance.

This invention was made in view of these points, and is a self-extinguishing method (a method in which the arc is extinguished by dissociation, decomposition, and ionization of the arc, as well as flow, diffusion, and cooling effects due to the pressure-increasing action).
By combining a small puffer device with excellent large current shearing characteristics and small current shearing characteristics, we provide a large-capacity switch that exhibits excellent shearing performance over the entire current range. be.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

As shown in FIG. 1, a contact flange 1 houses a fixed contact 2 therein. A hollow contact 3 having a through hole 7 faces the fixed contact 2 so as to be movable toward and away from it, and is attached to the tip of a movable rod 4 that moves up and down. Hollow hole 14 communicating with through hole 7 at the center
A relatively small-volume puffer cylinder 5 is attached to the movable rod 4, which has a puffer chamber 18 together with a puffer piston 6 fixed to the lower flange 10.
is formed. The puffer chamber 18 communicates with the hollow hole 14 via a communication port 17 formed on the side of the movable rod 4. The arc contact 8 supported by the contact flange 1, that is, the closing member, deeply enters and closes the through hole 7 of the movable contact 3 when both the contacts 2 and 3 are closed, and when they are opened, the arc contact 8, that is, the closing member, enters deeply into the through hole 7 of the movable contact 3 and closes it. Helps increase pressure. A cylindrical insulating tube 9 attached to the lower part of the contact flange 1 has a lower flange 10 fixed to its lower end, and the insulating tube 9, the lower flange 10, the puffer cylinder 5, and the puffer piston 6 form a pressure storage tank with an appropriate internal volume. (Concave chamber) 11 is formed. An exhaust port 12 through which the arc contact 8 passes is formed in the center of the contact flange 1, and has an opening area suitable for suppressing an excessive pressure rise occurring within the pressure accumulating tank 11. An exhaust port 15 is formed at the lower end of the hollow hole 4 provided in the movable rod 4, and a closing wall at the lower end of the puffer piston 6 is provided until the pressure in the pressure storage tank 11 increases sufficiently at the initial stage of opening. 1
6 is closed. At the same time, this does not prevent an increase in pressure within the puffer chamber 18.

In the device configured in this way, when a tripping command is given to an operating device (not shown) and the movable rod 4 interlocked with the operating device is driven downward by the operation of the operating device, the contacts 2 and 3 Move the appropriate wiping dimension to open the electrode. During this operation, the arc-extinguishing fluid in the puffer chamber 18, which is composed of the puffer cylinder 5 and puffer piston 6 attached to the movable rod 4, has its opening closed by the arc contact 8 and the closing wall 16, so the pressure decreases. It has increased to a value necessary for cutting. Further, the movable rod 4 descends, and the arc generated between the contacts 2 and 3 is commutated between the movable contact 3 and the arc contact 8. The arc is extended within the pressure storage tank 11 as the movable rod 4 moves downward. At this time, if the rupture current is relatively small and the pressure in the pressure storage tank 11 does not reach the value required for rupture, the arc-extinguishing fluid stored in the puffer chamber 18 compensates for this and quickly extinguishes the arc. I refuse. If the break current is large and the pressure in the pressure storage tank 11 is sufficient, as the current converges to zero, the arc-extinguishing fluid flows out through the movable contact 3 and the exhaust port 12, and the movable contact A strong blow is applied to the arc between the child 3 and the arc contact 8 to quickly extinguish the arc. The pressure inside the puffer chamber 18 is not so high for cutting off a small current, and the amount of spray is not large, so the puffer device can be small and the increase in operating force is small. , can be almost ignored.
Even when a large current is interrupted, sufficient blowing force can be ensured by the pressure increase in the pressure storage tank 11. For this reason, it is small and economical, with almost no increase in operating force.
Moreover, a highly practical switch with excellent performance can be obtained. FIG. 2 shows another embodiment. In contrast to FIG. 1, where the puffer cylinder 5 is the movable element, this embodiment uses the puffer piston 6 as the movable element, and the lower part of the movable rod 4. The only difference is that the exhaust port 15 provided in the second embodiment is omitted, and the other configurations are similar to those shown in FIG. 1 and perform the same function.

As described above, according to the present invention, it is possible to obtain a compact switch that has excellent damping performance over the entire current range without increasing the operating force.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part showing one embodiment of the present invention, and FIG. 2 is a sectional view of a main part showing another embodiment of the invention. Note that the same reference numerals in the figures indicate the same or corresponding parts. In the figure, 2 is a fixed contact, 3 is a movable contact, 4 is a movable rod, 8 is an arc contact, that is, a closing member, 11 is a pressure storage tank, 14 is a hollow hole, 17 is a communication port, and 18 is a puffer chamber.

Claims (1)

[Claims] 1 A pressure accumulator having an opening on one side through which arc-extinguishing fluid enters and exits, a fixed contact provided at the outlet of the opening, and a hollow hole, which penetrates the pressure accumulator and moves in the direction of the penetration. A movable rod having a hollow movable contact that is freely provided and comes into contact with and separates from the fixed contact; and a puffer that is provided on the outer periphery of the movable rod and that accumulates pressure when the movable contact opens and separates. a chamber, a communication port formed on the side of the movable rod and communicating between the puffer chamber and the hollow hole, and a communication port provided opposite to the movable contact when the two contacts are closed. A closing member that loosely fits into the terminal and closes it, and maintains the closed state while the movable contact moves to a predetermined distance.