JP6078378B2 - Circuit breaker - Google Patents

Description

  The present invention relates to a circuit breaker.

  The circuit breaker is provided with an arc extinguishing part that extinguishes an arc generated when current is interrupted.

  Japanese Patent Application Laid-Open No. H10-228561 discloses a technique for preventing damage to a contact by suppressing a reverse flow phenomenon of an arc.

JP 2006-120643 A

  A general arc extinguishing part is composed of a support plate and a magnetic iron plate, but it may be difficult to improve the interruption performance of the arc extinguishing part alone.

  As a conventional technique, a partition plate made of an insulating material is attached between the magnetic iron plate and the contact portion, and the volume of the movable contact fixed contact and the movable contact near the movable contact is reduced, so that there is an effect of narrowing the arc. The short circuit interruption performance is improved.

  However, since the magnetic iron plate of the arc extinguishing part is covered with the partition plate, it is assumed that the arc cooling effect is weakened when the DC small current region (10 to 30 A) is interrupted by opening, in that case, It is assumed that it cannot be shut off.

  Therefore, there is a need for a circuit breaker that has a high short-circuit breaking performance and also improves the breaking performance in the DC small current region.

  In the present invention, since the exposure of the magnetic iron plate in the vicinity of the contact portion is reduced by attaching a partition plate to the arc extinguishing portion in the conventional technique, it is an object to improve the interruption performance in a small current region where the arc driving force is small. And

  In order to solve the above problems, a partition plate made of an insulating material is provided on the side of the fixed contact and the movable contact, and the partition plate has a hole or a notch so that the side magnetic iron plate is exposed.

  Further, by providing the magnetic iron plate with a convex portion, the magnetic iron plate can be caused to protrude from the hole or notch of the partition plate, and the magnetic iron plate can be brought close to the contact portion.

  In addition to the function of narrowing the arc, the partition plate made of an insulating material such as an organic material such as melamine evaporates the insulating material such as an organic material due to the heat generated by the arc at the time of opening, causing a gaseous state. Therefore, the arc extinguishing gas contributes to the function of extinguishing the arc and improving the interruption performance.

  Here, the said structure is demonstrated below by another expression.

A contact portion having a movable contact of a movable contact that opens and closes a main circuit and a fixed contact of a fixed contact, an arc extinguishing portion that houses a forward contact portion, and a movable contact in contact with the fixed contact An opening / closing mechanism that drives the movable contact so as to close a certain pole or open a non-contact state, and after detecting an overcurrent or a short circuit current of the main circuit, opens the movable contact In a circuit breaker that extinguishes an arc generated at the time of opening of the contact portion provided with a tripping portion for operating the opening / closing mechanism portion,
The arc-extinguishing part has a support plate oriented parallel to the direction of opening / closing operation of the movable contact, and the support plate is disposed so as to sandwich the movable contact that opens and closes the two relative to each other. A plurality of magnetic iron plates provided in a direction perpendicular to the support plate between the two support plates, and a partition plate of an insulating material provided in parallel to the support plate on the side of the contact, The partition plate has a hole or a notch, and has a portion where the magnetic iron plate is exposed.

  Further, the magnetic iron plate is provided with a convex portion so that the convex portion protrudes or protrudes from a hole or notch in the partition plate.

  Further, the magnetic iron plate in the vicinity of the contact portion of the contact portion is exposed by a notch provided in the partition plate.

  The partition plate is positioned closer to the contact portion than the U-shaped magnetic iron plate surrounding the contact portion and is in contact with the inside of the support plate.

  The partition plate is made of an insulating material such as an organic material.

  As mentioned above, by providing a hole or notch in the partition plate and exposing the magnetic iron plate, the arc cooling effect is maintained by opening and closing in the small current region, and by the effect of narrowing the arc by the partition plate Short circuit breaking performance can be improved.

  In particular, the magnetic iron plate in the vicinity of the contact portion of the contact portion of the fixed contact and the movable contact is not covered with the partition plate and continuously exposed, so that the arc cooling effect can be further enhanced and the arc can be easily interrupted.

  In addition, the partition plate is in contact with the inside of the magnetic iron plate, so that the partition plate is positioned, and the magnetic iron plate serves as a support for the partition plate against the increase in internal pressure when shut off, improving the strength of the partition plate Can be planned.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the circuit breaker which improved the interruption | blocking performance compared with the past.

Structure diagram of circuit breaker of embodiment of the present invention Sectional drawing of the arc extinguishing part of the Example of this invention Arc extinguishing part (closed state) of an embodiment of the present invention Arc extinguishing part of the embodiment of the present invention (contact opening operation (initial)) Arc extinguishing part of the embodiment of the present invention (opened state)

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the structure of a circuit breaker, and FIG. 2 shows a cross-sectional view of the arc extinguishing part of the present invention.

  The circuit breaker of the present embodiment includes a contact portion 11 having a movable contact of a movable contact for interrupting the current of the main circuit and a fixed contact of a fixed contact, and an opening / closing mechanism portion 12 for opening and closing the contact portion. The tripping device 13 trips the switching mechanism 12 under conditions such as overcurrent, and the arc extinguishing unit 14 cools and extinguishes the arc between the contacts when the contacts open.

  As shown in FIG. 2, the arc extinguishing portion is composed of a support plate 21, a magnetic iron plate 22, and a partition plate 23. In the present embodiment, a convex portion of the magnetic iron plate 22 and a hole or a notch portion of the partition plate 23 are provided in the contact track area. The magnetic iron plate 22 is uncovered and exposed even when the partition plate 23 is attached.

  Thereby, it has the high interruption | blocking performance at the time of short circuit interruption | blocking by the narrowing-down effect of the arc by the partition plate 23, and the arc cooling effect can be maintained and the arc can be interrupted by the opening and closing of the small current region by the exposure of the magnetic iron plate 22.

  Further, the partition plate 23 may use an organic insulating material such as melamine.

  In addition to the function of narrowing the arc, the partition plate made of an insulating material such as an organic material such as melamine evaporates the insulating material such as an organic material due to the heat generated by the arc at the time of opening and becomes a gaseous state. As the arc extinguishing gas, it contributes to the function of extinguishing the arc and improving the interruption performance.

  FIG. 3 shows a structural diagram of the closed state of the arc extinguishing portion of the present embodiment. In order to further improve the arc cooling effect, the lowermost magnetic iron plate 22 closest to the contact portion of the fixed contact 32 and the movable contact 31 is The structure is exposed without being covered with the partition plate 23.

  FIG. 4 shows a structural diagram at the initial stage of the opening operation of the contact of the arc extinguishing portion of this embodiment.

  In the initial stage of the opening operation of the contact portion between the fixed contact 32 and the movable contact 31, an arc is generated between the contacts between the fixed contact 32 and the movable contact 31.

As described above, the lowermost magnetic iron plate 22 closest to the contact portion between the fixed contact 32 and the movable contact 31 is not covered with the partition plate 23 and is exposed, and is projected on the magnetic iron plate on the side of the contact portion 32. And a structure in which the magnetic iron plate is exposed from the partition plate. In order to cut off the arc within 10 ms, it is important to cut off the arc with the second and third magnetic iron plates 22 from the contact portion of the fixed contact 32 and the movable contact 31 based on the opening speed of the movable contact. is there. By using this structure, the magnetic iron plate 22 that is first exposed to the arc at the time of opening can be disposed near the movable contact 31, and the arc driving force by the magnetic iron plate 22 can be maintained even at a low DC current,
It is possible to enhance the arc cooling effect.
In alternating current, the timing of passing the zero point, that is, the timing when the current value becomes zero is periodically repeated because of the characteristics of the current change. Therefore, when AC is interrupted, the arc can be extinguished and interrupted by waiting for the zero point or the timing when the current value becomes zero and performing the arc extinguishing operation in accordance with this timing.

  However, since direct current does not pass through the zero point, it is generally known that arc extinction and interruption are more difficult than alternating current.

  In addition to this direct current characteristic, in the case of a small current, it is expected that arc extinguishing and interruption will become more difficult as described above.

  On the other hand, by adopting a structure in which a convex portion is provided on the magnetic iron plate on the side of the contact portion 32 of this embodiment, the arc extinction and interruption performance is improved even in the case of a small DC current. is there.

  FIG. 5 shows a structural diagram of the contact open state of the arc extinguishing portion of this embodiment.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and the shape and arrangement of components and the like are changed as appropriate, or the materials are changed to more suitable ones. It is good.

11: Contact part, 12: Opening and closing mechanism part, 13: Tripping device, 14: Arc extinguishing part, 21: Support plate, 22: Magnetic iron plate, 23: Partition plate, 31: Movable contact, 32: Fixed contact, 33: Movable contact stand, 34: fixed contact stand.

Claims (5)

A contact portion having a movable contact of a movable contact that opens and closes a main circuit and a fixed contact of a fixed contact;
And the extinguishing unit that housed the previous Symbol contact part,
An opening and closing mechanism that drives the movable contact to the movable contact Ru is thereby closing a contact to the fixed contact or non-contact state opening,
After detecting an overcurrent or short circuit current, of the main circuit, and a tripping unit that operates the opening and closing mechanism portion of the movable contact so as to opening, the arc generated during opening of the contact portion with a a circuit breaker for extinguishing,
The arc extinguishing part has a support plate oriented parallel to the direction of opening and closing operation of the movable contact,
The support plates are provided in parallel so that the two plates are opposed and sandwich the movable contact that opens and closes.
A plurality of magnetic iron plates are provided between the two support plates in a direction perpendicular to the support plate,
The Setsuban specifications on the side of the contact portion is provided in parallel with the support plate,
Wherein the lack holes or cut provided in the partition plate, the circuit breaker according to claim and Turkey to expose the magnetic iron plate of the contact portion near the contact track region and the contact portion. A circuit breaker according to claim 1,
The magnetic iron projections provided on the plate, the circuit breaker, characterized in that said protrusion from outs hole or cut of the partition plate is projected, or out. The circuit breaker according to claim 1, wherein
The partition plate is closer to the contact portion than the U-shaped magnetic iron plate surrounding the contact portion.
Thus, the circuit breaker is disposed in contact with the inside of the magnetic iron plate. The circuit breaker according to claim 1, wherein
A circuit breaker characterized in that the partition plate is made of an insulating material, an organic material, or melanin. A contact portion that includes a movable contact of the movable contact and a fixed contact of the fixed contact, and interrupts the current of the main circuit;
An arc extinguishing part for accommodating the contact part;
An opening / closing mechanism for driving the movable contact so that the movable contact and the fixed contact are in a contact state or a non-contact state;
A circuit breaker comprising: a trip unit that operates the switching mechanism unit so that the movable contact and the fixed contact are in a non-contact state after detecting an overcurrent or a short circuit current of the main circuit,
The arc extinguishing part has a partition plate provided on the side of the contact part and a plurality of magnetic iron plates,
The circuit breaker according to claim 1, wherein when the partition plate has a hole or a notch, the magnetic iron plate in the contact track region and in the vicinity of the contact portion of the contact portion is exposed.

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