JPH0451373Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Technical field to which the idea belongs]

The present invention relates to a DC electromagnetic contactor equipped with a permanent magnet type arc extinguisher on a normally closed contact.

[Prior art and its problems]

DC electromagnetic contactors generally generate an arc between the contacts when the current is interrupted, making it difficult to interrupt the current. Therefore, an arc extinguishing device is used to extinguish this arc, and an insulating barrier is required to insulate between this arc extinguishing device and the current-carrying parts. It becomes necessary. An example of an electromagnetic contactor having a normally closed contact of this type is shown in FIGS. 6 to 8. In Fig. 6, a pair of main circuit terminals 2 are attached to the case 1 facing each other through both side walls, and a pair of main circuit terminals 2 each consisting of upper and lower sides facing each other with an interval and a connecting side are connected to the main circuit terminals 2. A U-shaped fixed contact 3 is arranged. An interlocking rod 4 that reciprocates in the vertical direction is provided between the opposing fixed contacts 3, 3, and the upper end of the interlocking rod 4 is movable to enable bridging between the contacts 3a of the fixed contacts 3. A contactor 5 is attached, and the lower end of the interlocking rod 4 is attached and supported by a movable core 6 of the electromagnet device. The movable iron core 6 is constantly pushed up by a return spring (not shown), so that the contact 5a of the movable contact 5 contacts the contact 3a, bridging the opposing contacts 3a, 3a. An arc extinguishing device 7 is provided in the opening/closing section constituted by both contacts 3 and 5, and this arc extinguishing device 7 includes a magnetic pole plate 8, an insulating barrier 9, a permanent magnet 10, as shown in FIGS. 7 and 8.
It is composed of a coupling fitting 11. The insulating barrier 9 is a magnetic pole side barrier 9a that covers the magnet plate 8 and the permanent magnet 10.
and a conductor-side barrier 9b that covers the inside of the connecting side of the fixed contact 3, and by connecting these, the lower side of the fixed contact 3 is isolated from the movable contact 5. A magnetic pole plate 8 and a permanent magnet 10 are fitted into recesses on both outer sides of the magnetic pole side barrier 9a, and a coupling fitting 11 made of an elastic thin plate bent into a U-shape is inserted from below the insulating barrier 9. , the protrusion 11a provided at the end of the coupling fitting 11 is engaged with the protrusion 9c provided on the insulating barrier 9, and the coupling fitting 1
Magnetic pole plate 8, insulation barrier 9, permanent magnet 1 with both legs of 1
They are joined together so as to embrace 0. 11
b is a protrusion cut and raised from the bottom of the coupling fitting 11, and serves as a mark for determining the position of the arc extinguishing device 7, and by extension the fixed contact 3, and the polarity of the permanent magnet 10. This arc extinguishing device 7 is connected to the fixed contact 3 with a screw 12 using a hole provided in the conductor side barrier 9b. The fixed contact 3, the arc extinguishing device 7, and the insulating barrier 9 are combined in this way, and the main circuit terminal 2a is fixed to the case 1 with the screw 13 as described above.
2b with screws 14, and covered with a lid 1a. When the electromagnet device (not shown) is energized, the movable iron core 6
is attracted and moves downward, pulling down the interlocking rod 4 and separating the movable contact 5 from the fixed contact 3. At this time, an arc is generated between both contacts 3a and 5a,
Since the arc extinguishing device 7 is provided so that magnetic flux exists in a direction perpendicular to the arc, the arc tends to move left and right in FIG. 6 due to Fleming's left hand rule. Therefore, if the direction of the magnetic flux is appropriately selected, the arc can be pushed outside the opening/closing part, making the arc longer and extinguishing it. At this time, the insulating barrier 9 insulates between the arc and the arc extinguisher 7 or the fixed contact 3. By the way, this DC electromagnetic contactor has a large number of screws because most of the members are assembled by screwing. Of course, screws are convenient for disassembly, but they have the disadvantage that they require a lot of man-hours for drilling and assembly, and require a large number of parts. Another drawback is that the screw occupies a larger area, resulting in a larger size.

[Purpose of the invention] The object of the invention is to improve the connection of members using screws, reduce the number of processing and assembly steps, and provide a compact, inexpensive DC magnetic contactor that is easy to assemble.

[Key points of the idea]

The present invention has a fixed contact formed approximately in a U-shape and having a fixed contact on the upper side and arranged opposite to each other, and a main circuit terminal attached to the lower side of the fixed contact.
A movable contact that has a movable contact and is supported by an interlocking rod that reciprocates between the fixed contacts and constantly bridges the fixed contacts, and a movable contact that is arranged to sandwich the opposing movable contact and the fixed contact, respectively. , an arc extinguishing device having magnetic pole pieces coupled to each other via a permanent magnet, and an arc extinguishing device provided so as to cover the opposing magnetic pole surfaces of the arc extinguishing device, the lower side of the fixed contact, and the inside of the connecting side from the movable contact. In the DC electromagnetic contactor, which is equipped with an insulating barrier and housed in a case, the fixed contact is integrally welded to a main circuit terminal which is fixed by caulking leaf springs that are perpendicular to the length direction and protrude on both sides. Alternatively, both ends of a leaf spring that has been brazed and fixed to the main circuit terminal are press-fitted into the groove of the case to fix the main circuit terminal to the case, and the arc extinguishing device and the insulating barrier are integrated by adhesive. Conductive parts that do not require disassembly, such as main circuit terminals and fixed contacts, are fixed to the case by press-fitting or adhesive, and are integrated by brazing, welding, etc., and are attached by caulking a leaf spring. By press-fitting the arc extinguishing device into the case and bonding it with the insulating barrier by adhesive, it eliminates the need for tightening screws for assembling a DC magnetic contactor, which requires a large number of parts, making it compact, inexpensive, and easy to assemble. This is what we are trying to do. Note that the arc extinguishing device and the insulating barrier may be integrated and held by elastic protrusions provided inside the cover and spaced apart from each other.

[Example of idea]

An embodiment of the present invention will be described in detail with reference to FIGS. 1 to 5. In Fig. 1, the overall structure of the DC magnetic contactor is almost the same as the conventional one, with a pair of main circuit terminals 2 installed through both side walls of a case 1, and a lower side of the main circuit terminals 2 attached to the case 1. a pair of fixed contacts 3 facing each other; a movable contact 5 bridging between the fixed contacts 3;
A permanent magnet 1 connects each magnetic pole piece 8 provided to sandwich both contacts 3a and 5a of the fixed contact 3 and the movable contact 5, and the magnetic pole piece 8.
0, and a movable contact 5 between the arc extinguisher 7, the lower side of the fixed contact 3, and the connecting side.
Although the insulating barrier 9 is provided to cover the insulating barrier 9, the bonding structure between them is significantly different from the conventional one. In other words, parts that do not interfere when assembling this electromagnetic contactor or do not need to be separated when disassembling the magnetic contactor should be joined by brazing, caulking, or adhesive whenever possible, and parts that are necessary for assembly or disassembly should be joined by press-fitting. are doing. Only the points that differ from the conventional one will be explained below. First, as shown in FIG. 2, the main circuit terminal 2 and the fixed contact 3 are fixed at their lower sides to the main circuit terminal 2 by brazing. A leaf spring 15 is fixed to the main circuit terminal 2 by caulking so as to be orthogonal to the length direction thereof, and protrudes laterally from the terminal 2. When the terminal 2 and the fixed contact 3 are integrated, the protrusion of the leaf spring 15 is connected to the partition wall of the case 1.
It is installed by inserting it into the groove 1b provided in the section a.
The arc extinguishing device 7 is integrated with the insulating barrier 9 by adhesive. The insulation barrier 9 is approximately U as shown in FIG.
The magnetic pole side barrier 9a is formed in a shape of a letter, and the conductor side barrier 9b protrudes between each side of the U-shaped legs of the magnetic pole side barrier 9a. A rectangular parallelepiped permanent magnet 10 is bonded to the outer bottom surface of the barrier 9a, and a magnetic pole piece 8 is bonded to the outer side of the opposing U-shaped leg. At this time, one of the magnetic pole pieces 8 is provided with a protrusion 8a below as shown in FIG.
By setting the magnetic pole on the side as N or S, it is possible to prevent wrong polarity during assembly. This integrated arc extinguishing device 7 and insulating barrier 9 has two elastic protrusions 1d spaced apart from each other on the inside of the cover 1a as shown in FIG. It is pressed and held by this elastic protrusion 1d. FIG. 5 shows that an integrated arc extinguishing device 7 and an insulating barrier 9 are dropped into the bulkhead where the normally closed contacts of the case 1 are attached, and are inserted into the elastic protrusion 1 of the cover 1a.
d shows the pressed state, and 5d is a movable contact having a normally open contact. The integrated arc extinguishing device 7 and insulating barrier 9 may be press-fitted between the partition walls 1b shown in FIG. 5, or may be glued together, thereby reducing the number of screws 12 required in the past. . In any case, when installing this arc extinguishing device,
The protrusion 8a of the magnetic pole piece 8 fits into the recess of the case 1, thereby determining the position of the arc extinguisher and the polarity of the permanent magnet 10. The operation of this electromagnetic contactor is similar to that of the conventional one, so a description thereof will be omitted.

[Effect of the idea]

In the electromagnetic contactor according to the present invention, parts that do not need to be separated are joined together by brazing or adhesive, and parts that need to be disassembled are press-fitted between grooves or partitions in the case, or are held down with a cover. This eliminates the need for tightening screws, making assembly and disassembly easier and saving man-hours. Also, since no tightening screws are used, there is no need for mounting holes, which saves man-hours.
It also has the advantage that the members can be made smaller and the whole can be assembled into a smaller size.

[Brief explanation of the drawing]

Figures 1 to 5 show an embodiment of the DC electromagnetic contactor according to the present invention, with Figure 1 being a side sectional view and Figure 2 being a perspective view showing the mounting structure of the main circuit terminal and fixed contact to the case. 3 are perspective views showing the combination of the arc extinguishing device and the insulating barrier, FIGS. 4 and 5 show examples of how the arc extinguishing device is attached, and FIG. 4 is a sectional view showing the relationship with the cover. Fig. 5 is a sectional view taken along the line X-X in Fig. 1, Figs. 6 to 8 show conventional examples of DC magnetic contactors, Fig. 6 is a side sectional view, and Figs. 7 and 8. 7 shows a coupled state of the arc extinguisher and the insulating barrier, FIG. 7 is a side view, and FIG. 8 is a front view of FIG. 7. 1... Case, 1a... Cover, 1b... Case groove, 1d... Elastic protrusion, 2... Main circuit terminal,
3... Fixed contact, 3a... Fixed contact, 4... Interlocking rod, 5... Movable contact, 5a... Movable contact, 7
... arc extinguishing device, 8 ... magnetic pole piece, 8a ... protrusion of magnetic pole piece, 9 ... insulation barrier, 10 ... permanent magnet, 1
5... Leaf spring.

Claims (1)

[Claims for Utility Model Registration] 1. A fixed contact that is approximately U-shaped and has a fixed contact on its upper side and is placed facing each other at a distance, and a main circuit terminal that is attached to the lower side of the fixed contact. a movable contact having a movable contact and supported by a moving rod that reciprocates between the fixed contacts and constantly bridging the fixed contacts; an arc extinguishing device having magnet pieces arranged and coupled to each other via permanent magnets, and covering the inner side of the opposing magnetic pole faces of the arc extinguishing device and the lower side and connecting side of the fixed contact from the movable contact. In the DC electromagnetic contactor, which is housed in a case and has an insulating barrier provided as shown in FIG. Both ends of the leaf spring, which is welded or brazed to the main circuit terminal and fixed to the main circuit terminal, are press-fitted into the groove of the case to fix the main circuit terminal to the case, and the arc extinguishing device and the insulating barrier are integrated by adhesive. A direct current electromagnetic contactor, characterized in that the contactor is fixed to the case by press fitting or adhesive. 2. In the DC electromagnetic contactor described in claim 1 of the utility model registration claim, an integrated arc extinguishing device and an insulating barrier are pressed and held by elastic protrusions provided at a distance from each other on the inside of the cover. A DC magnetic contactor featuring: