JPS5849553Y2 - Magnetically driven gas shield disconnector - Google Patents

Description

[Detailed description of the invention] This invention relates to the improvement of a magnetically driven gas breaker, more specifically a breaker of the type that extinguishes an arc by rotating it in an insulating arc-extinguishing gas such as SF. The purpose is to improve the interrupting performance, especially in the small current range, with a simple structure.

As is well known, in this type of gas circuit breaker, after an arc is generated between the contacts at the time of circuit breaker, the circuit breaker transfers the circuit breaker current to a magnetic drive coil, causes the magnetic flux generated by this coil to cross the arc, and extinguishes the arc in an arc extinguishing gas. The arc is extinguished by rotation.

FIG. 1 is a sectional view of a main part of a conventional device of this type, with the right side of the center line X showing the on state and the left side showing the cut off state.

Here, a movable contact 2 that is in sliding contact with a fixed contact 1
When they are opened, an arc is generated between the two liquid contactors, but this is commutated to the arc runner 3 and a breaking current is applied to the magnetic drive coil 4 wound between the arc runner 3 and the fixed contact base 5. The arc 6 due to the magnetic flux generated by flowing
is driven to rotate, and the surrounding arc-extinguishing gas G is relatively blown to extinguish the arc.

Note that for convenience of explanation, the breaker operating device and container are omitted.

By the way, in the structure shown in FIG. 1, since the arc 7 near the movable contact is far from the drive coil 4, the magnetic field is weaker than that near the fixed contact, and the driving force is reduced accordingly.

This phenomenon becomes a problem particularly when interrupting a small current range where the magnetic field generated by the drive coil 4 becomes weak, and the arc time may become longer.

As a result of various studies, the inventor attempted to solve the above problem by providing a floating nozzle, and the main idea will be explained below.

FIG. 2 is a cross-sectional view of the breaker section showing one embodiment of the present invention, in which the right side of the center line X shows the closed state, the left side shows the cut-off state, and the chain double-dashed line shows the cut-off state.

In addition, FIG. 3 is a plan view showing an example of a floating nozzle, and FIGS.
FIG. 6 shows another embodiment of the present invention.

In the embodiment shown in FIG.
A stepped portion 8 is provided so that when the movable contact 2 slides on the movable contact 2 and moves downward to a specific position, the nozzle 9 follows this movement.

Further, a pressure spring 11 is provided between the movable rod 13 and the nozzle 9 to bias the nozzle in the direction of closing the movable contact 2.

Further, the nozzle 9 is provided with a plurality of gas flow holes 10, so that the exhaust gas flows through the arc 7 near the tip of the movable contact.
It is constructed so that it can be sprayed on.

As shown in FIG. 3, this flow hole 10 may be inclined in two directions, the circumference and the central axis X, if necessary, so that the exhaust gas rotates around the arc, and in this case, the direction of the exhaust gas is may be tilted in the same direction as the driving direction of the arc or in the opposite direction.

Furthermore, it is convenient if the upper diameter D1 of the communication hole is smaller than the lower diameter D2, since the discharge effect can be improved.

The nozzle 9 may be made entirely or partially of an arc-resistant insulating material, a magnetic material, or a metal material.

Otherwise, the same reference numerals as in FIG. 1 indicate the same or equivalent parts.

Next, the operation will be explained.

In the structure shown in Fig. 2, when a command to perform a cutoff operation is given to the operating device, the movable contact 2 moves downward, and after the sliding period, the fixed contact 1 and the movable contact 2 separate and an arc occurs during this time. Occur.

On the other hand, when the movable contact 2 moves downward to a predetermined position, the stepped portion 8 provided on the movable contact 2 engages with the floating nozzle 9, and this nozzle 9 also moves downward, collecting the surrounding insulating arc-extinguishing gas. A gas flow F flowing toward the tip of the movable contactor 2 is generated from a plurality of gas flow holes 10 provided in the gas nozzle 9.

The movable contact 2 and the nozzle 9 move further downward, and when the tip of the movable contact 2 is removed from the arc runner 3, the arc easily moves between them and becomes an arc 6.

As the arc moves to the arc runner 3, current flows through the magnetic drive coil 4 as shown by the two-dot chain line, and a magnetic flux that crosses the arc is generated, so the arc 6 is rotationally driven by electromagnetic force. At the same time, it is blown by the gas flow F generated by the nozzle 9.

The movable contactor 2 moves away from the magnetic drive coil 4 according to the opening operation, and the arc 7 at its tip receives less driving force from the coil magnetic field, but is sufficiently cooled by the blowing of the gas flow F, and in combination with the magnetic drive force. The arc 6 is easily extinguished.

When a small current is interrupted, the magnetic driving force received by the arc 7 near the movable contact of the arc 6 decreases because the magnetizing current decreases, and therefore the magnetic flux decreases, but due to the effect of the blowing of the floating nozzle 9, the arc The arc is easily extinguished.

In the embodiment shown in FIG. 2, the gas flow hole 1 provided in the nozzle 9
0 is inclined only in the direction of the central axis X to effectively direct the gas flow toward the arc 7 near the movable contact, but as shown in Fig. By arranging the arc at an angle, the rotational driving force of the arc by the gas flow F can also be obtained, which is even more effective.

At this time, the direction in which the arc is rotated by the gas flow and the direction in which it is driven by the magnetic drive may be matched to compensate for the rotational driving force by the magnetic field, or conversely, the gas flow may adjust the angle of the gas flow hole to match the direction in which the arc is driven by the magnetic drive. As mentioned above, the contact effect between the fresh arc-extinguishing gas G and the arc may be compensated for by increasing the relative flux of the gas flows that collide with the arc so that they are opposed to each other in the rotational direction. That's right.

The gas flow holes 10 may be replaced by gaps between rib-shaped support pieces that support the nozzle 9, or the inclination of the rib-shaped pieces may provide an oblique spraying effect.

In addition, as shown in FIG. 4, the nozzle 9 is configured to protrude beyond the movable contact 2, and the base of the arc 6 is further blown away by spraying gas in the lateral direction to the arc 6. It may be possible to make the arc extinguishing more effective and more rapid.

Although the above explanation mainly focused on the effect of the shape of the floating nozzle, when part or all of the floating nozzle 9 is made of a magnetic material, the external leakage portion of the magnetic flux generated by the drive coil 4 is absorbed by the nozzle 9. Since the induction can be concentrated in the vicinity, the magnetic flux density in the vicinity of the movable contactor 2 can be increased, and the rotation of the arc 6 can be made more effective.

Furthermore, as shown in FIG. 5, the floating nozzle 9 may act as a piston 15 in combination with a fixed cylinder 14, or as shown in FIG. It may also be used in combination with the fixed piston 17, and in these cases the blowing action in the latter half of the operation can be further increased.

As detailed above, according to the present invention, when the movable contact that slides into contact with the fixed contact that has a magnetic drive coil on its outer periphery moves in the opening direction to a predetermined position, the floating nozzle moves to follow the movable contact. Since the gas is collected and blown near the tip of the movable contact, the arc in the vicinity of the movable contact, which follows the opening operation and becomes far away from the magnetic drive coil and is difficult to be influenced by this magnetic field, is well cooled. This makes it possible to improve the interrupting performance in a small current range where the magnetic driving force is small.

Moreover, it has a simple structure and has extremely practical effects.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of the main parts of a conventional device, and Figure 2 is a part of the proposed device.
FIG. 3 is a plan view showing one example of a floating nozzle, and FIGS. 4 to 6 each show one side of the main portion sectional view showing other embodiments of the present invention. 1...Fixed contact, 2...Movable contact, 3...Arc runner, 4...Drive coil, 5...Fixed contact Child stand, 6... Arc, 7... Arc near movable contact, 8...
...Stepped portion, 9...Idle nozzle, 10...
... Gas flow hole, 11 ... Pressure spring, 12.
...Central hole, 13...Movable rod, 14...
... Fixed cylinder, 15 ... Piston, 1
6... Movable cylinder, 17... Fixed piston, Φ... Magnetic flux, G... Arc-extinguishing gas, F... Gas flow .

Claims (1)

[Scope of utility model registration request] 1. a fixed contact disposed in an insulating arc-extinguishing gas; a magnetic drive coil disposed on the outer periphery of the fixed contact and one end of which is connected to the fixed contact; and the other end of the magnetic drive coil. an arc runner connected to the lower end of the magnetic drive coil; a movable contact that slides into and out of contact with the fixed contact; and a movable contact disposed around the outer circumference of the movable contact so that the movable contact is in a predetermined position. a floating nozzle that starts a follow-up operation to collect the gas and sprays the gas near the tip of the movable contact through a plurality of gas flow holes; A magnetically driven gas breaker that is characterized by a suppression spring that biases the air in the opposite direction, and a magnetically driven gas breaker that provides even more control. 2. The magnetically driven gas breaker according to claim 1, wherein the floating nozzle is made of a magnetic material. 3. The magnetic drive according to claim 1, wherein the gas flow hole of the floating nozzle is perforated obliquely with respect to the central axis and radial direction of the movable contact and sprays a rotating gas flow. Shaped gas cutter. 4. The magnetically driven gas breaker according to claim 1, wherein the tip of the floating nozzle is made to protrude from the tip of the movable contact and sprays a nearly lateral gas flow. 5. The magnetically driven gas breaker according to claim 1, wherein the diameter of the gas flow hole of the floating nozzle is reduced along the closing direction of the movable contact.