JPH0535531Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an arc extinguishing device for circuits and breakers.

[Prior Art] An arc extinguishing device for a circuit breaker is provided to face a movable contact and a fixed contact of the circuit breaker, and the It is used to extinguish arcs that occur. In other words, when the movable contact moves away from the fixed contact,
An arc is generated between both contacts, and the generated arc is stretched in the direction of the arc extinguishing grid due to the electromagnetic action of the arc current and the magnetic flux formed through the arc extinguishing grid of the arc extinguishing device by its own arc current. The elongated arc collides with the arc extinguishing grid, breaks it up, cools it, and extinguishes it.

FIG. 5 shows the configuration of a conventional circuit breaker arc extinguishing device (hereinafter simply referred to as an arc extinguishing device). In the figure, the conventional arc extinguishing device includes a support frame 1 having a substantially U-shaped cross section, a plurality of arc extinguishing grids 2 held in parallel on the support frame 1 with gaps in between, and arc extinguishing grids 2 on the support frame 1. A top plate 3 is provided which is supported in parallel to the grid with a gap therebetween. As shown in Fig. 2, the arc extinguishing grid 2 provides a space (spatial escape) for a movable contact (not shown) to perform opening and closing operations when used as an arc extinguishing device in a circuit or breaker. This is caused by an arc that collides with the approximately V-shaped groove 22 forming the part), the plurality of protrusions 21 that engage with the engagement holes 12 provided in the support frame 1, and the arc extinguishing grid 2, causing the arc to break. It has a notch 23 for letting high pressure gas escape. The cutout portion 23 is not particularly necessary when the arc extinguishing grid 2 is supported with a gap provided in the support frame 1. The top plate 3 is made of a resin material or a metal plate, and has an engagement hole 13 provided near the upper end of the support frame 1.
It has a protrusion 31 for engaging with, and is formed in a step-like shape. The support frame 1 is, for example, a single insulating plate bent so that the cross section is approximately U-shaped. 2 and the engagement hole 12 for engaging with the protrusions 21 and 31 of the top plate 3
and 13. Further, a hole 11 is provided on the back side of the support frame 1 for discharging high-pressure gas caused by an arc.

Next, the operation of the conventional arc extinguishing device configured as described above will be explained. In a circuit breaker having a general configuration shown in FIG. 6, a movable contactor 10
1 from the fixed contact 100, an arc is generated as is well known. As described above, the arc is extinguished by colliding with the arc extinguishing grid 2, but at this time, high-temperature gas is generated inside the arc extinguishing device. Since the arc extinguishing device is surrounded on both sides and above by the support frame 1 and the top plate 3, the internal space of the arc extinguishing device is held, is filled and compressed, and becomes high pressure gas. The compressed high-pressure gas is ejected to the outside of the arc extinguisher from a hole 11 provided at the upper part of the back surface of the support frame 1. This jetting temporarily lowers the pressure inside the arc extinguishing device, and new air is introduced from the opening forming the substantially U-shaped cross section of the support frame 1, thereby increasing the arc cooling effect.

[Problems to be solved by the invention] Since the conventional arc extinguishing device is constructed as described above, the top plate 3 is assembled by engaging each protrusion 31 with the engagement hole 13 of the support frame 1. At the same time, a plurality of arc extinguishing grids 2 must be engaged with the protrusions 21 of each arc extinguishing grid 2 into the engagement holes 12 of the support frame 1. Therefore, the top plate 3 has a more complicated shape than the arc extinguishing grid 2, requires dimensional accuracy, and is difficult to assemble.

This invention was made in order to solve the above-mentioned problems, and the purpose is to provide an inexpensive arc extinguishing device that facilitates assembly work by forming the top plate 3 and the support frame 1 integrally. It is said that

[Means for Solving the Problems] The arc extinguishing device for circuit breakers and circuit breakers according to this invention includes a plurality of arc extinguishing grids that are held in parallel with each other through gaps, and a plurality of arc extinguishing grids that are A support frame having a substantially U-shaped cross section for holding the support frame side by side, and an end portion of at least one of the three sides constituting the substantially U-shaped cross section of the support frame is extended, and the extended extension is provided. The extended portion is bent so as to overlap the arc extinguishing grid held in parallel, and the bent extension portion is configured to engage at least one other of the three sides.

[Function] The end of at least one of the three sides constituting the substantially U-shaped cross section of the support frame, which is extended and bent so as to overlap with the arc extinguishing grid, acts as the top plate of the conventional example and prevents circuits. or when used as a disconnector,
Together with the side plates of the support frame, it surrounds the upper part of the arc extinguishing device to keep the high pressure gas generated by the arc inside the arc extinguisher.

Since the bent end portion engages with the other surface, the arc extinguishing device will not be disassembled and destroyed even if high pressure gas is generated due to arc generation inside the arc extinguishing device.

[Example] The arc extinguishing device for circuit breakers and circuit breakers according to this invention was
This will be explained using the embodiments shown in FIGS. 2 and 3.

Fig. 1 is a perspective view showing the configuration of an arc extinguishing device for circuits and breakers (hereinafter simply referred to as arc extinguishing device) according to this invention, and Fig. 2 shows an arc extinguishing grid similar to the conventional example. FIG. FIG. 3 is a developed view of the support frame 50 of the arc extinguishing device shown in FIG. In FIG. 1, a plurality of arc extinguishing grids 2 are held side by side on opposing sides 51 and 58 of a support frame 50, and are covered above by top plate portions 52 and 54 of the support frame 50.

In FIG. 3, the support frame 50 has side portions 51, 58 and a back portion 59, and the side portions 51, 58 are bent approximately at right angles to the back portion 59 along bending lines C and D, respectively, so as to be perpendicular to the paper surface. This constitutes three surfaces having a substantially U-shaped cross section. The arc extinguishing grid 2 is the same as that of the conventional example as shown in FIG. It has a plurality of protrusions 21 for. Further, if necessary, a notch 23 may be provided for releasing high-pressure gas caused by arc generation.

Each of the side parts 51 and 58 of the support frame 50 has a plurality of engagement holes 521 arranged in parallel at predetermined intervals in order to hold the arc extinguishing grids 2 in parallel, for example.
have. Each of the side portions 51 and 58 has extension portions 52 and 54 at their ends, respectively, which function as the conventional top plate 3 by being bent substantially at right angles along bending lines A and B. The side portion 51 has an engaging portion 55 for engaging with the protrusion 54a of the extended top plate portion 54.
The side portion 58 has an engaging portion 53 for engaging with a protrusion 54a of the top plate portion 52 extending from the side portion 51. The back portion 59 of the support frame 50 has a hole 510 for blowing out gas associated with arc generation when assembled as an arc extinguishing device.

The arc extinguishing device is assembled, for example, in the following steps.

(1) From the developed view shown in FIG. 3, bend the top plate parts 52 and 54 along bending lines A and B, respectively, at right angles to the side parts 51 and 58 (perpendicular to the plane of the paper).

(2) Using a jig or the like (without limitation), the plurality of arc extinguishing grids 2 are inserted into the engagement holes 521 in which the protrusions 21 of each are provided in the side parts 51 and 58 of the support frame 50.
are temporarily held in parallel so as to engage with each other.

(3) While a plurality of arc extinguishing grids 2 are temporarily held in parallel on the back part 59 of the support frame 50 using the above-mentioned jig or the like, the side parts 51 and 58 are attached to the back part 59 along the bending lines C and D. Bend it at right angles to the

In the above procedure, especially in the third step, the respective protrusions 21 of each arc extinguishing grid 2 are connected to the engagement holes 52 of each side 51 and 58 of the support frame 50.
At the same time, the protrusion 52a of the top plate part 52 and the engaging part 53 of the side part 58, and the protrusion 5 of the top plate part 54
4a and the engaging portion 55 of the side portion 51 engage at the same time. At the same time, the lower side protrusion 57 of the top plate part 54 and the upper side protrusion 56 of the top plate part 52 engage with the upper side 52b of the top plate part 52 and the lower side 54b of the top plate part 54, respectively.

Generally, as described above, between each protrusion of each arc extinguishing grid 2 and the engagement hole 521 provided in the side plates 51, 58 of the support frame 50, and between the protrusions 52a, 54a of each top plate part 52, 54, each Engagement portion 5 of side plates 58, 51
3 and 55 to facilitate engagement, each arc extinguishing grid 2 is not connected to the support frame 50 in the arc extinguishing device assembled by the above procedure. It is in a state where it can move slightly (there is so-called wobbling). Therefore, support frame 5
Each arc extinguishing grid 2 is attached to the support frame 50 by caulking each protrusion 21 of the arc extinguishing grid 2 protruding from each engagement hole 521 of the side parts 51, 58 of 0 with a punch or the like and crushing the protruding portion of the protrusion 21. Fix it firmly. Similarly, the protrusion 52 of each top plate portion 52, 54
a, 54a and the engaging portion 5 of each side portion 58 and 51
It goes without saying that the top plate parts 52 and 54 of the support frame 50 are firmly engaged with the side parts 58 and 51 by performing caulking while the parts 3 and 55 are in the engaged state. In the embodiment shown in FIG. 1, there is an opening 511 at the top, but when this arc extinguishing device 50 is used as a circuit or disconnector as shown in FIG. It is closed by the outer container 11.

FIG. 4 shows another embodiment of the arc extinguishing device for circuits and breakers according to this invention. The embodiment shown in FIG. 4 is a further simplified version of the embodiment shown in FIG. 1, and is configured such that one top plate portion 52 covers the entire arc extinguishing device.

The operation of the arc extinguishing device constructed as described above when used in the circuit and disconnector shown in FIG. 6 will be described. An arc is generated when the movable contact 101 of the circuit breaker is separated from the fixed contact 100, but the arc is caused by the arc current and the electromagnetic action of the arc extinguishing grid 2 of the arc extinguishing device 50 to the arc extinguishing grid side. It is stretched out and collides with the arc extinguishing grid 2. The arc that collides with the arc extinguishing grid 2 is divided, cooled, and extinguished, but at this time, high temperature and high pressure gas is generated inside the arc extinguishing device. This high-temperature, high-pressure gas is surrounded by the arc extinguisher's support frame 50 having a substantially U-shaped cross section, the top plate portions 52 and 54 of the support frame 50, the outer container 11 of the circuit breaker, etc., and is inside the arc extinguisher. Stay in. The high-temperature, high-pressure gas remaining in the arc extinguisher is ejected from the hole 510 provided in the back 59 of the support frame 50, and the pressure in the arc extinguisher is temporarily reduced. When the pressure inside the arc extinguisher decreases, new air flows in from the opening on the side facing the movable contact of the arc extinguisher to equalize the pressure, reducing the pressure inside the arc extinguisher to the outside. The pressure becomes constant and cools down.

[Effects of the invention] As described above, this invention has the effect that the number of parts can be reduced and the assembly can be simplified by integrating the top plate, which has conventionally been a separate part.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an embodiment of an arc extinguishing device for a circuit or breaker according to this invention, and Fig. 2 is an illustration of an arc extinguishing grid 2.
3 is a developed view of the support frame 50 in FIG. 1, FIG. 4 is a diagram showing another embodiment of the circuit breaker arc extinguishing device according to this invention, and FIG. FIG. 6 is a diagram showing the configuration of a general circuit breaker. In the figure, 2 is an arc extinguishing grid, 50 is a support frame, and 5
1, 58 is the side part, 52, 54 is the top plate part, 53, 5
5 is an engaging portion.

Claims (1)

[Claims for Utility Model Registration] A plurality of arc extinguishing grids held side by side with gaps interposed between them, and a support frame having a substantially U-shaped cross section for holding the plurality of arc extinguishing grids side by side. In the arc extinguishing device for a circuit or disconnection device, an extension part extending an end of at least one of the three faces constituting the substantially U-shaped cross section of the support frame is held in parallel. An arc extinguishing device for a circuit or breaker, characterized in that the arc extinguishing grid is bent to overlap with the arc extinguishing grid, and the bent extension is engaged with at least one other of the three surfaces.