JPH0142254Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an arc extinguishing device for an electromagnetic contactor, and more particularly to an arc extinguishing device for an electromagnetic contactor that covers the main circuit contacts of the electromagnetic contactor and extinguishes the arc generated when the contacts are opened. .

An electromagnetic contactor is a device that opens and closes main circuit contacts to control the opening and closing of electrical circuits in motors, etc., but this device is equipped with an arc extinguishing device to quickly extinguish the arc that occurs when the contacts open. There is.

Fig. 1 shows the configuration of the main parts of a conventional electromagnetic contactor including an arc extinguishing device. An operation coil is attached to a fixed core (not shown), and the excitation of the operation coil causes a movable iron to move. The main circuit contacts were opened and closed by moving them into and out of the fixed iron core.

That is, a cross bar fixed to the movable core is provided with a movable contact 12 having a movable contact 10 at one end, and a fixed contact 18 having a fixed contact 16 is fixed to the base 14, so that the two cores can be connected and separated. The main circuit was opened and closed by connecting and separating both contacts 10 and 16.

In order to extinguish the arc when both contacts 10 and 16 open, the electromagnetic contactor is provided with an arc extinguishing device, and the arc extinguishing device is configured as follows. That is, an arc box 20 is provided on the base 14 so as to cover both contacts 10 and 16.
is fixed, and a plurality of caulking fixing holes 22 are provided in the upper part of the arc box 20.
The arc box 20 is made of a heat-resistant material such as glass-containing thermosetting resin or porcelain in order to prevent burnout due to arc heat generated when the contacts 10 and 16 are opened. Further, a grid 24 as shown in FIG. 2 is fixed to the caulking fixing hole 22 of the arc box 20 by caulking at a caulking part 24a, and the tip of the grid 24 is extended above the fixed contact 18. There is. As a result, the arc 26 generated when both the contacts 10 and 16 are opened is propagated to the fixed contact 18, the grid 24, and the movable contact 12 one after another, and the arc 26 is divided and extinguished.

However, in the conventional arc extinguishing device for an electromagnetic contactor, the caulking part 24a having the same wall thickness as the grid 24 is inserted into the caulking fixing hole 22 of the arc box 20 and fixed by caulking, so a strong caulking force is required. Need and also Arkbox 2
The shape of the 0 had to be large enough to withstand strong crimping force.

Furthermore, as mentioned above, the arc box 20 is made of glass-filled thermosetting resin or porcelain, so even if the arc box 20 is
However, there is a drawback that the edge portion 22a of the caulking fixing hole 22 may be damaged due to strong caulking force.

Furthermore, in the conventional electromagnetic contactor arc extinguishing device, the caulked portion 24a of the grid 24 is largely exposed to the outside of the arc box 20.
The drawback was that it looked bad.

The present invention was devised in view of the above-mentioned conventional problem, and its purpose is to eliminate the need for strong crimping force when inserting and crimping the crimping part of the grid into the crimping fixing hole of the arc box, and To provide an arc extinguishing device for an electromagnetic contactor that can prevent damage to the edge part of a caulking fixing hole, further downsize an arc box, and improve the appearance of the device. be.

In order to achieve the above object, the present invention moves a movable core toward and away from the fixed core by excitation of an operating coil attached to the fixed core, and interlocks a crossbar attached to the movable core to connect the movable core to the fixed core. An electromagnetic contactor that connects and disconnects a movable contact to a fixed contact to control the opening and closing of an electric circuit, includes an arc extinguishing device that extinguishes an arc when the contact is opened, and the arc extinguishing device has a plurality of caulking fixing holes. an arc box that covers both contacts, and a plurality of grids that have a caulked part with a thin wall at the tip that guides the arc and extinguishes the arc.
, the thin tip of the caulking portion of each grid is inserted into each caulking fixing hole of the arc box from the movable contact and fixed contact side so as to start from the inside of each caulking fixing hole, The grid is fixed to the arc box by bending the thin tip of the caulked portion protruding from each caulking fixing hole of the arc box.

Preferred embodiments of the present invention will be described below based on the drawings.

FIG. 3 shows a preferred embodiment of the arc extinguishing device for an electromagnetic contactor according to the present invention. In the figure, the same members as those in the conventional example described above are designated by the same reference numerals, and the explanation thereof will be omitted.

The characteristic feature of this invention is that the wall thickness at the tip of the caulking part of the grid is thinned, and the thin tip of the thinned caulking part starts from inside each caulking fixing hole of the arc box. The grid is inserted into the hole, and the portion of the tip protruding from the hole is bent to fix the grid to the arc box.

That is, as shown in FIG.
The tip 24b of the caulked part 24a of No. 4 is connected to the grid 2.
This caulking part 24a is inserted into the caulking fixing hole 22 of the arc box 20 so that the tip part 24b starts from inside the hole 22, and the tip part 24b is formed thinner than the wall thickness of the arc box 20. It is bent and caulked as shown by the arrow.
Here, the caulking fixing hole 22 and the caulking part 24a of the grid 24 are respectively a square hole and a square protrusion of a size that can be inserted and fixed without rattling.

Therefore, according to this embodiment, the arc 26 due to the thin thickness of the tip portion 24b of the caulked portion 24a
While preventing the blow-out, the following effects can be obtained.

That is, in the present invention, the caulking portion 24a
Since the wall thickness of the tip portion 24b of the grid 24 is thin, strong crimping force is not required when crimping and fixing the grid 24 to the arc box 20, and the shape of the arc box 20 can therefore be made smaller. Furthermore, damage to the edge portion 22a of the caulking fixing hole 22 can be prevented.

Furthermore, in the present invention, when the caulked portion 24a is caulked and fixed to the arc box 20, only the thin tip portion 24b is exposed from the arc box 20, so that the appearance can be improved.

As explained above, the present invention includes an arc box having a plurality of caulking fixing holes and covering both contacts, and a plurality of grids having a caulking part with a thinner tip and guiding the arc and extinguishing the arc. , the thin-walled tips of the caulking portions of each of the grids are bent and fixed to the holes in the arc box so that the tips start from inside the caulking fixing holes, so that the caulking portions of the grids can be arc-fixed. When inserting into the crimping fixing hole of the box and crimping it in place, strong crimping force is not required, and damage to the edge of the crimping fixing hole can be prevented, and furthermore, the arc box can be made smaller. Furthermore, the appearance of the device can be improved, and the above effects can be obtained while preventing arc blow-out from the vicinity of the tip of the caulked portion of each grid.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main parts of a conventional arc extinguishing device for a magnetic contactor, Fig. 2 is an external view of the grid in Fig. 1, and Fig. 3 is an arc extinguishing device for a magnetic contactor according to the present invention. FIG. 4 is an external view of the grid shown in FIG. 3. In each figure, the same members are given the same reference numerals, 20 is the arc box, 22 is the caulking fixing hole, 24 is the grid, 24a is the caulking part, 24b is the tip, 2
6 is an arc.

Claims (1)

[Scope of utility model registration request] The movable core is moved toward and away from the fixed core by excitation of the operating coil attached to the fixed core, and the crossbar attached to the movable core is interlocked to move the movable contact provided on the crossbar toward and away from the fixed contact, thereby opening the electric circuit. An electromagnetic contactor that performs opening/closing control includes an arc extinguishing device that extinguishes an arc when the contacts are opened, and the arc extinguishing device includes an arc box that has a plurality of caulking fixing holes and covers both contacts; a plurality of grids each having a caulked portion with a thin wall at the tip for guiding an arc and extinguishing the arc; The grid is inserted into each caulking fixing hole from the side of the movable contact and fixed contact so as to start, and a part of the tip protruding from each caulking fixing hole of the arc box is bent, and the grid is inserted into the arc box. An arc extinguishing device for an electromagnetic contactor, characterized in that the arc extinguishing device is fixed to a magnetic contactor.