JPH0524099Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic contactor, and more particularly to an improvement in an electromagnetic contactor having an arc box in which a plurality of discharge ports for arced gas generated by an arc are provided corresponding to arc extinguishing chambers.

As this type of electromagnetic contactor, one shown in FIG. 1 has been proposed. That is, the reference numeral 10 designates a base, in which a fixed core (not shown) facing a movable core 38 of a cross bar 36 (to be described later) is installed inside the base, and a fixed core 10 is provided on the end plate 12 on the upper surface of the base in a predetermined direction (in a direction perpendicular to the plane of the paper). External connection terminal plates 14 for each phase of R, S, and T are fixed at intervals, and U-shaped fixed contacts 18 having fixed contacts 16 are fixed on these terminal plates 14.

20 is an insulating barrier that insulates between the terminal boards 14;
2 is an arc runner fixed to the fixed contact 18.

Reference numeral 24 denotes an arc box connected to the left side of the base 10, and an arced gas discharge port 28 is formed in the ceiling plate 26 of the arc box.

Reference numeral 30 denotes an arc extinguishing chamber formed within the arc box 24, in which a plurality of grids 32 facing the arc runner 22, a commutation plate 34, etc. are arranged, and an R.
They are arranged between each phase of ST and T, respectively.

Reference numeral 36 is a crossbar, and a movable iron core 38 is fixed to the lower end thereof extending into the base 10 by a pin 40, and a movable contactor extending into the arc extinguishing chamber 30 can be slid up and down. installed. In this case, the movable contact 42 is fixed to a movable contact holder 46 that is engaged with the left inner surface of a square frame 44 that is slidably disposed within the cross bar 36.
A movable contact 48 facing the fixed contact 16 is fixed to both left and right ends thereof, respectively. On the other hand, corner frame 4
4 is pressed downward by a compression spring 52 which is inserted in a compressed state between its upper inner surface and a stopper 50 which passes through the inside and is fixed to the cross bar 36, so that the movable contact 42 is biased toward the fixed contact 18 via a movable contact holder 46. 17 is a buffer rubber inserted between the cross bar 36 and the movable iron core 38.

Next, the effect will be explained. When magnetic flux is generated in the fixed core in the base 10, the movable core 38 is attracted, the crossbar 36 moves downward (in the direction of arrow A) against a tripping spring (not shown), and the fixed contacts 16 and The movable contact 48 abuts to establish electrical continuity between the upper and lower external connection terminal plates 14 .

From this state, when the magnetic flux of the fixed iron core (not shown) is eliminated, the crossbar 36 returns to the original position shown in the figure due to the pressing force of the tripping spring, and the fixed contact 16
and the movable contact 48 is separated. At this time, an arc is generated between the fixed contact 16 and the movable contact 48.
This arc is transferred from the fixed contact 16 to the arc runner 22 and from the movable contact 48 to the commutator plate 34, and is further drawn into the grid 32 by the electromagnetic repulsion of the arc current and the contact current, and is cooled and
It is divided and extinguished.

However, in such a conventional electromagnetic contactor, since the arced gas discharge port 28 is provided in the ceiling of the arc box 24, the arced gas containing ionized metal generated by the arc is discharged from the gas discharge port in the ceiling. The gas flows toward the gas discharge port 28 and is discharged to the outside through the gas discharge port 28. Therefore, if the distance between the panel fan surface and the arc box ceiling is not wide enough, the ionized metal contained in the blown out arced gas will ground the panel fan surface, causing a ground fault or a short circuit between phases, resulting in a shutdown or There was a problem that could cause a short circuit accident. This would not be a problem if the distance between the fan surface of the board and the ceiling of the arc box was widened, but since the depth of the board was regulated, it was not possible to make it wider.

The present invention has been devised in view of the above-mentioned conventional problems, and its purpose is to install a non-magnetic metal material that is non-magnetic and air permeable to the arc box, which forms at least a part of the arc extinguishing chamber. By disposing an arced gas absorber formed of a spongy or porous member having An object of the present invention is to provide an electromagnetic contactor that can solve the above problems.

In order to achieve the above object, the present invention includes a plurality of arc extinguishing chambers formed adjacent to each other, an arc box forming at least a part of the outer shell of the arc extinguishing chamber, and a corner extinguishing section in the arc box. An electromagnetic contactor comprising a plurality of arced gas discharge ports formed corresponding to the arc chambers, and an arced gas absorber mounted in each of the corner arc extinguishing chambers facing the arced gas discharge ports and isolated by an insulator. The arced gas absorber is characterized in that it is made of a spongy or porous member that is made of non-magnetic metal and has air permeability.

Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIGS. 2 and 3 are diagrams showing an embodiment of the present invention.

In FIG. 2, parts corresponding to those in FIG. An arced gas absorber 56 made of magnetic metal is mounted, and this arced gas absorber 56 is fixed by an arc cover 58. The material for the arced gas absorber may be any non-magnetic metal that can withstand the temperature of the arced gas, such as Ni-Cr alloy (stainless steel) or Cu-Su-Zn alloy (bronze). That is, the arced gas absorber 56
The purpose is to use a non-magnetic metal for the arced gas absorber 56, and the arced gas absorber 56 is a non-magnetic material that has temperature characteristics that can withstand the temperature of the arced gas, and has cavernous or porous characteristics and is made of metal. That's fine. The arced gas absorber 56 is manufactured by, for example, foaming a resin to create a three-dimensional mesh, attaching metal to the mesh by electroplating, and then removing the resin. As a result, the portions from which the resin has been removed become voids and are porous. Alternatively, another method may be to press-form metal powder and heat it at a high temperature to weld the metals together. In this case, the gaps between the metals become voids and a porous body is formed.

As is particularly clear in FIG. 3, the arc cover 58 forms a square 62 corresponding to each arc extinguishing chamber 30 by a barrier 60 for preventing short circuit between phases.
A plurality of arced gas discharge ports 64 are drilled in the top plate portion. The arc cover 58 is fixed to the upper surface of the arc box 24 with screws or the like, with the arced gas absorber 56 housed in each square 62.

As shown in FIG. 3, inside each square 62, an arced gas absorber 56 having a corresponding shape
It is designed to accommodate.

Next, the effect will be explained. An electromagnetic attraction force is generated between the fixed core (not shown) and the movable core 38, and the movable core 38 is moved toward the fixed core, and the crossbar 36 is pulled out against the spring (not shown). When moved in the direction A, the fixed contact 16 and the movable contact 48
are in contact with each other, and electrical continuity is established between the external connection terminals 14.

From this state, when the electromagnetic attraction force between the fixed core and the movable core 38 is eliminated, the crossbar 36 returns to its original position above by the return force of the tripping spring.
The movable contact 48 is separated from the fixed contact 16. At this time, an arc is generated between the fixed contact 16 and the movable contact 48. This arc is transmitted from the fixed contact 16 to the arc runner 22 and from the movable contact 48 to the commutation plate 3.
4, and is further drawn between the grids 32 by the electromagnetic repulsion between the arc current and the contact current, and is cooled and separated to extinguish the arc. The arced gas containing ionized metal generated by the arc flows toward the discharge port 28 in the ceiling of the arc box 24 and is discharged into the arced gas absorber 56 through the discharge port 28. Then, the arced gas containing electrons and ions contains ionized molten metal that has evaporated or dissociated from the contacts 16 and 48 and the grid 32. When this arced gas passes through the arced gas absorber 56, the mechanism in which molten metal adheres to and is absorbed by the arced gas absorber 56 is that when ions approach the arced gas absorber 56, electrostatic induction causes ions to A negative charge is generated between the arced gas absorber 56 and an attractive force is generated between the negative charge and the ions, so that the ions are attracted to the arced gas absorber 56. When the molten metal passes through the three-dimensional mesh porous space of the arced gas absorber 56 together with the arced gas, when it comes into contact with a metal having a high thermal conductivity, it is significantly cooled and adheres to the arced gas absorber 56.

Ions generated from the non-metal mold material and air are significantly cooled by the arced gas absorber 56, and in the process of becoming a low-temperature gas, the ions are recombined with electrons to become atoms and are emitted to the outside. Furthermore, by forming the arced gas absorber 56 with a non-magnetic material, the arc that should be extinguished in the arc extinguishing chamber by the magnetic grid 32 is prevented from being drawn into the arced gas absorber 56 by the electromagnetic force of the arc. By increasing the arc-extinguishing ability, it is possible to completely prevent ground contact with a metal surface such as a panel fan surface due to ionized substances being blown out of the device, and
Phase-to-phase short circuits can also be prevented. Therefore, since there is no need to provide a wide gap between the panel and the fan surface, a standard panel can be used and an inexpensive panel can be selected.It is an electromagnetic contact that is extremely reliable, has excellent breaking performance, and is highly safe. equipment can be provided.

[Brief explanation of drawings]

FIG. 1 is a side view of a conventional electromagnetic contactor with the right half sectioned, and FIG. 2 is a side view of the right half section of an embodiment of the electromagnetic contactor with an arc cover according to the present invention. FIG. 3 is a perspective view showing the arc cover and the arced gas absorber. The same members in each figure are given the same reference numerals, 10 is the base, 14 is the external connection terminal, 16 is the fixed contact, 1
8 is a fixed contact, 22 is an arc runner, 24 is an arc box, 28 is an arced gas discharge port, 3
0 is an arc extinguishing chamber, 36 is a crossbar, 42 is a movable contact, 48 is a movable contact, 56 is an arced gas absorber, 58 is an arc cover, and 64 is an arced gas discharge port.

Claims (1)

[Scope of utility model registration request] A plurality of arc extinguishing chambers are formed adjacent to each other and are isolated for each phase, and a chamber is provided corresponding to the plurality of arc extinguishing chambers, forms a part of the outer shell of each arc extinguishing chamber, and is activated by an arc. In an electromagnetic contactor equipped with an arc box having a plurality of discharge ports for discharging generated arced gas, the plurality of arced gas discharge ports of the arc box have openings corresponding to the plurality of discharge ports, and the arced gas is discharged. An arc cover is installed that has an interphase short-circuit prevention barrier formed in a square shape so that each phase is isolated and discharged to the outside, and each square is made of a spongy or porous non-magnetic metal. An electromagnetic contactor characterized by housing an arced gas absorber.