JPS6029788Y2 - Vacuum cutting device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a vacuum breaker or breaker device that makes it possible to cool a ring contact portion that is in sliding contact with a movable lead rod.

Fig. 1 shows a vacuum breaker having a pole column structure. In Fig. 1, 1 is a base, and a first insulator pipe 4 having an insulating rod 3 inside is installed in the base 1 via a flange 2. be done.

A second porcelain tube 7 having a vacuum container 6 therein is fixed to the upper end of the first porcelain tube 4 via a conductive end plate 5 .

8 is a support fitting that supports the vacuum container 6;
is electrically connected to the end plate 5 and this end plate 5
is fixed to.

9 is a fixed lead rod, and 10 is a movable lead rod.

The movable lead rod 10 is projected to the outside of the vacuum container 6 via the bellows 25.

This protruding portion 10a is in sliding contact with a ring contact 11 disposed in the penetrating portion of the support fitting 8, and the protruding portion 10a
The end portion of the insulating rod 3 is connected to the insulating rod 3 via a coupling 12.

The coupling 12 is fitted into the through hole 8a of the support fitting 8.

Note that the end plate 5 is provided with an insertion hole 5a for the insulating rod 3 and a ventilation hole 5b.

Reference numeral 13 denotes a cylinder constituting an air operation mechanism, and a piston 14 is fitted into the cylinder 13.

The piston 14 is connected to the cylinder 1 via a piston rod 15.
It is projected to the outside of 3.

The piston rod 15 is inserted through the flange 2 and into the first insulator tube 4, and is connected to the insulating rod 3 by a coupling 16.

17 is a cutoff spring loaded in the cylinder 13;
8 is an input air supply port.

Reference numeral 19 denotes a nearing air supply pipe, and this supply pipe 19 is attached to the flange 2.

20.21 is a terminal.

In the vacuum breaker configured as described above, the nearing air from the nearing air supply pipe 19 flows into the first insulator pipe 4, passes through the vent hole 5b of the end plate 5, and passes through the second insulator pipe 7.
is flowing into the country.

The nearing air that has flowed into the second insulator tube 7 passes through the gap between the vacuum container 6 and the second insulator tube 7 and is exhausted to the outside from an exhaust hole formed in the upper part.

In this way, the first. The purpose of passing nearing air through the second insulator tubes 4 and 7 is to maintain dielectric strength, and has almost no effect on cooling the heat generating parts as described below.

When the vacuum breaker is energized, the current is
flows to terminals 20.21.

Due to this current, the movable lead rod 10 and the ring contact 11 in particular generate heat.

The heat generated in this area cannot be radiated to some extent by the support fitting 8.

As a result, it has not been possible to obtain a vacuum breaker of this type that carries a large current.

This invention was made in view of the above-mentioned circumstances, and the purpose is to provide a vacuum breaker that improves the cooling effect and enables the passage of a large current.

An embodiment of this invention will be described below with reference to FIG. 2. The same parts as in FIG. 1 are designated by the same reference numerals.

In FIG. 2, the support fitting 8 is of a cap shape having a ventilation hole, a space 22, and a fitting part 8a for the coupling 12 as described later, and has a plurality of first holes coaxially with the fitting part 8a. A pore 23 is bored.

The first ventilation hole 23 has a lower portion communicating with the insertion hole 5a of the end plate 5, and an upper portion communicating with the space portion 22.

Reference numeral 24 denotes a plurality of small diameter second ventilation holes drilled in the upper part of the support fitting 8 as shown in detail in FIG.
An axial direction 24a drilled coaxially with the support bracket 8 and a radial direction 24b drilled in the radial direction of the support bracket 8 are communicated within the support bracket 8.

As described above, the first and second ventilation holes 23 and 24 are provided in the support fitting 8.
By drilling the nearing air, when the nearing air sent from the nearing air supply pipe 19 flows into the first insulator pipe 4, the nearing air passes through the first ventilation hole 23 from the insertion hole 5a of the end plate 5. and flows into the space 22.

The nearing air flowing into the space 22 flows through the second ventilation hole 2
4.

At this time, since the diameter of the second ventilation hole 24 is small, the second ventilation hole 24
The nearing air passing through 4 exhibits the same effect as a nozzle, and increases its flow rate.

During this passage, the nearing air passes through the ring contact 11
The heat generated in the vicinity of is removed and discharged from the axial hole 24a through the radial hole 24b, thereby cooling this heat generating portion.

The nearing air discharged from the radial hole 24b passes through the gap between the vacuum container 6 and the second insulator tube 7, and is exhausted from an exhaust hole (not shown) provided in the upper part.

As mentioned above, the movable lead rod 10 and the ring contact 11
Since the parts can be cooled, a large current can be passed, and the current rating can be increased.

FIG. 4 shows another embodiment of the second ventilation hole 24, in which the axial hole 24
The diameter of a is formed to be small as in the previous embodiment, but the passage cross-sectional area of the radial hole 24c is increased to increase the flow velocity passing through the axial hole 24a, thereby improving the cooling effect. This is what I tried to do.

The second ventilation hole 24 may not be formed in a hook shape but may be formed in an oblique shape as shown by the imaginary line in FIG. 4.

As mentioned above, according to this invention, the nearing air is made to flow through the small-diameter ventilation hole that is drilled close to the ring contact of the support metal fitting, so the parts that generate a lot of heat can be reliably cooled. This has the effect that large current can be passed without enlarging the shape of the current-carrying part.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a conventional vacuum breaker, Fig. 2 is a sectional view showing an embodiment of this invention, Fig. 3 is an enlarged sectional view of the main part of Fig. 2, and Fig. 4 is a sectional view of an embodiment of this invention. FIG. 7 is an enlarged sectional view of another embodiment. 1... Base, 3... Insulating rod, 4...
...First insulator tube, 5...End plate, 6...
...Vacuum container, 7...Second insulator tube, 8...
・Supporting metal fittings, 10...Movable lead rod, 11...
... Ring contact, 19 ... Air supply pipe, 22 ... Space, 23 ... First ventilation hole, 24 ... Second passage Stomata, 24a...
- Axial hole, 24b...Radial hole.

Claims (1)

[Scope of utility model registration request] A first insulator tube 4 having an insulating rod 3 planted on the base 1 and into which nearing air is supplied; a second insulator tube 7 connected to the upper part of the first insulator tube via an end plate 5; Second
A vacuum container 6 housed in an insulator tube 7, a movable lead rod 10 protruding from the container and connected to the insulating rod, and a movable lead rod inserted between the end plate 5 and the vacuum container 6. A vacuum breaker comprising a support fitting 8 with a ring contact 11 provided on the sliding part, and a small-diameter vent hole 24 that is bored close to the ring contact of the support fitting and allows the nearing air to flow through it. Device.