JPH05298991A - Electromagnetic contactor - Google Patents

Abstract

PURPOSE:To reduce repulsion of a main movable contact even when a main circuit voltage drops by forming a plurality of slots on a plate-like base, and reducing rigidity of a base surface resistant against pressure from a fixed iron core. CONSTITUTION:An insulating cover 19 is interposed between a plate-like base 20 fixed to an opening end of a main body case 1 for closing the end and a coil frame 3a of an electromagnet for driving a main movable contact contained inside the case 1, where the insulating cover 19 abuts at the bottom surface thereof against the end surface of the base 20 of a fixed iron core 5 of an electromagnet while covering an adequate range of the iron core 5 on a side of the base 20 so as to position the iron core 5 on the base 20 under guidance of a guide surface 20c formed on the base 20. A plurality of slots 20b in two rows are formed on the base 20 where the iron core 5 is pushed by a cushion spring 7 via the cover 19. Furthermore, slots 20b are formed in one row in the center. Consequently, it is possible to effectively absorb shock energy of a movable iron core 6 due to deflection of the base 20 and deformation of the cover 19, thus reducing repulsion of a main movable contact 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate-shaped base fixed to an open end surface of a main body case and an electromagnet coil for driving a main movable contact housed in the main body case. Between the winding frame and the electromagnet, the bottom surface of the fixed core of the electromagnet is covered with an appropriate range on the side of the plate-shaped base, and the bottom surface is brought into contact with the end surface of the fixed core on the side of the plate-shaped base and guided by the guide surface formed on the plate-shaped base. An electromagnetic contactor in which an insulating cover for positioning the fixed iron core on the plate-shaped base is arranged, and an end surface of the fixed iron core on the plate-shaped base side is pressed by the spring force against the plate-shaped base via the bottom surface of the insulating cover, The present invention relates to a structure of an electromagnetic contactor capable of effectively reducing the rebound of the main movable contact caused by the impact of the moving iron core moving end of the electromagnet when the main movable contact is closed-circuited.

[0002]

2. Description of the Related Art An example of the structure of a conventional electromagnetic contactor of this type is shown in FIG.
Through FIG. In this structural example, the electromagnetic contactor includes a main body case 1, a main movable contact drive electromagnet housed in the main body case 1, a main movable contact support 13 connected to a movable iron core 6 of the electromagnet, and a main movable contact. The main movable contact 10 which is always held by the contact support 13 while receiving the spring force of the main contact spring 12, the main fixed contact 9 which is fixed to the main body case 1, and the open end surface of the main body case 1 are closed. Plate-like base 9 fixed to the end face, and the fixed iron core 5 of the electromagnet.
Of the fixed core 5 and the fixed core support 14 that is press-fitted into the square hole near the end of the fixed base 9 on the side of the fixed base 5, and the bottom of the fixed core 5 contacts the end of the fixed core 5 on the side of the base 2. An insulating cover 19 that guides the fixed iron core 5 on the base 2 by being guided by the surface 2c, and a cushion spring interposed between the coil winding frame 3a of the electromagnet and the fixed iron core support 14 are main components. To be done.

When the movable core 6 of the electromagnet is attracted to the fixed core 5 when the electromagnetic contactor is closed, and the distance between the movable core 6 and the fixed core 5 becomes smaller near the end of the movement, the attraction force between the two cores becomes stronger, and the fixed core becomes stronger. 5 also moves toward the movable iron core 6 side against the cushion spring 7 and collides with the movable iron core 6 in a state where the fixed iron core 5 floats up from the base 2, and the mass difference between the movable iron core 6 and the fixed iron core 5 is not large. In addition, the rebound of the movable iron core 6 is reduced, the contact between the main movable contact 10 and the main fixed contact 9 is prevented from separating, the wear of the contact is reduced, and the life of the contact can be extended.

As another method of reducing the impact force at the moving end of the movable iron core 6 to reduce the rebound of the movable iron core 6, conventionally, a fixed iron core is held on the base side so as not to move to the movable iron core side. In addition, it is generally known that a cushioning rubber plate is inserted between the fixed iron core and the bottom surface of the insulating cover.

[0005]

As described above, even if the floating of the fixed iron core at the moving end of the movable iron core is used for impact mitigation, the load connected to the main circuit of the electromagnetic contactor is activated. If the attraction force between the movable iron core and the fixed iron core is reduced due to the voltage drop of the main circuit that constitutes the operating power supply due to the large torque motor or compressor etc., the movable iron core does not float up easily. When the body collides with the base of the end face of the main body case together with the fixed iron core, the force for holding the amount of bounce back to a small value is insufficient, and the problem arises that the main movable contact once contacted with the main fixed contact restarts and separates, resulting in increased contact wear. It turned out to be the case.

An object of the present invention is to provide a structure of an electromagnetic contactor capable of keeping the current cost of the electromagnetic contactor and reducing the rebound of the main movable contact even when the voltage of the main circuit drops.

[0007]

In order to solve the above-mentioned problems, in the present invention, an electromagnetic contactor having the structure described at the beginning, which is an object of the present invention, that is, an open end surface of a main body case is closed. Between the plate-shaped base fixed to the end face and the coil winding frame of the main moving contact driving electromagnet housed in the main body case, an appropriate range on the plate-shaped base side of the fixed core of the electromagnet is provided. The bottom surface of the fixed core contacts the end surface of the fixed core on the side of the plate-shaped base and is guided by the guide surface formed on the plate-shaped base to position the fixed core. An electromagnetic contactor whose end face on the base side is pressed against the plate-shaped base by the spring force via the bottom surface of the insulating cover is provided with a plurality of holes formed in the plate-shaped base to resist the pressing force from the fixed iron core side. Electromagnetic contact with weakened base surface rigidity The vessel.

Further, in the concrete structure based on this basic structure, the end face of the fixed core on the plate-like base side is formed in a square shape, and a plurality of holes formed in the plate-like base are formed in the longitudinal direction of the end face of the fixed iron core. It is preferable to have a structure in which a plurality of single holes or a plurality of rows are formed as long holes that are long in the longitudinal direction of the end surface of the fixed iron core. Furthermore, it is more preferable to form a plurality of protrusions on the surface of the bottom surface of the insulating cover on the side of the plate-like base, which presses the thick portions between the holes formed in the plate-like base.

[0009]

The present invention focuses on the fact that the base side end surface of the fixed iron core of the main movable contact driving electromagnet is held in a pressed state against the plate surface of the base via the bottom surface of the insulating cover that abuts against this end surface. It is a thing. The insulating cover having a shape that covers the end surface side of the fixed iron core and the bottom surface of the fixed iron core contacts the end surface of the fixed iron core is usually molded from a thermoplastic resin and has viscoelasticity as a mechanical property of the material. On the other hand, if multiple holes are formed in the base to reduce the rigidity of the plate surface against the pressure from the fixed iron core side, the plate surface will flex more for the same impact energy, and the insulation cover will be deformed accordingly. The amount also increases. The amount of rebound of the main movable contact is determined by the elastic energy remaining after being absorbed by deformation, so if there is no viscoelastic member and only the base absorbs the impact, the impact energy of the base is Even if the rigidity of the base is weakened, the elastic energy is converted into elastic energy and stored in the base, and the elastic energy stored in the base becomes equal to that in the case of the base having high rigidity, so that the amount of rebound is not reduced. However, when the viscoelastic member is interposed, a part of the impact energy is consumed by the viscous part, the energy accumulated as elastic energy in the viscoelastic member and the base is reduced, and the rebound is reduced. Therefore, the amount of rebound is effectively reduced by reducing the rigidity of the base and increasing the amount of deformation of the insulating cover.

Therefore, in the concrete structure based on the above basic structure, the end face of the fixed core on the plate-like base side is formed in a square shape, and a plurality of holes formed in the plate-like base are formed in the longitudinal direction of the end face of the fixed iron core. If multiple holes are formed in a single row or a plurality of rows in the longitudinal direction of the fixed iron core end face, the total length of the end face in the longitudinal direction of the rectangular end face of the fixed iron core will be replaced by a plurality of elongated holes. As can be easily understood if one long hole equal to is assumed, the deformation of the base becomes easier than that in the case of forming a plurality of round holes, etc., and the deformation of the insulating cover also increases accordingly. It can absorb energy effectively.

Further, as a concrete structure based on the above basic structure, a plurality of projections for pressing a thick portion between each hole formed in the plate-shaped base are formed on the surface of the bottom surface of the insulating cover on the plate-shaped base side. With such a structure, in addition to the deformation of the entire insulating cover due to the bending of the base, the impact energy is absorbed due to the deformation of the protrusions, so that the rebound of the main movable contact can be more effectively reduced.

[0012]

1 to 3 show an embodiment of the present invention.
1 is a plan view of an electromagnetic contactor having a structure according to the present invention, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. 3 shows a structure of a base formed according to the present invention. In these drawings, the same members as those in FIGS. 4 to 6 are designated by the same reference numerals and the description thereof will be omitted. The present invention is different from the conventional one in the structure of the base, and the surface of the plate-shaped base 20 against which the fixed iron core 5 is pressed by the cushion spring 7 via the insulating cover 19 (FIG. 2) is shown in FIG. ) And (b), the elongated holes 20b are formed in two rows and a plurality of rows in each row, or as shown in (c) of the figure, one additional row is added to the central portion to form a base surface. Is designed to be even more flexible. As the surface of the base 20 bends, the deformation of the insulating cover also increases, and this deformation effectively absorbs the impact energy of the movable core 6 and reduces the rebound of the main movable contact 10. In the case of FIG. 3 (c), the insulating cover 19 (FIG. 2) is not particularly shown here.
On the surface on the side of the base 20 of, the protrusions located between the elongated holes in the central one row are formed, and these protrusions are also deformed when the movable iron core 6 is impacted, thereby increasing the amount of impact energy absorption, The amount of rebound of the main movable contact 10 is effectively reduced.

[0013]

As described above, in the present invention, the electromagnetic contactor targeted by the present invention, that is, the plate-like member fixed to the open end surface of the main body case so as to close the open end surface. Between the base and the coil winding frame of the electromagnet for driving the main movable contact housed in the main body case, a plate-shaped base whose bottom surface is a fixed iron core covering an appropriate range of the plate-shaped base side of the fixed iron core of the electromagnet An insulating cover that contacts the side end face and is guided by a guide surface formed on the plate-shaped base to position the fixed core on the plate-shaped base is arranged, and the end face of the fixed core on the plate-shaped base side is insulated by spring force. The electromagnetic contactor pressed against the plate-shaped base through the bottom surface of the plate-shaped base has a plurality of holes formed in the plate-shaped base to weaken the rigidity of the base surface against the pressing force from the fixed core side. Therefore, at the end of the closed circuit operation of the electromagnetic contactor The deflection of the base surface of the magnet when the movable iron core is impacted is increased, and accordingly, the amount of deformation of the insulating base that covers the end of the fixed iron core on the base side is also increased, and the impact energy is effectively absorbed. It is possible to reduce the rebound of the main movable contact without increasing the cost, and thus it is possible to obtain an electromagnetic contactor with less contact wear even when the voltage of the electromagnetic contactor main circuit drops.

Then, the plate-shaped base side end surface of the fixed iron core is formed in a square shape, and a plurality of holes are formed in the base.
A plurality of single holes or multiple rows are formed in the longitudinal direction of the end face of the fixed iron core. By forming a long hole that is long in the longitudinal direction of the end face of the fixed iron core, compared to the case where the hole shape is circular, the base surface Is easily deformed, and the impact energy is absorbed more effectively.

If a plurality of protrusions for pressing the thick portion between the holes formed in the plate base are formed on the surface of the bottom surface of the insulating cover on the plate base side, the plurality of protrusions are formed. Due to the consumption of impact energy due to the deformation, the rebound of the main movable contact is further reduced, the wear of the main contact is further reduced, and the life of the contact can be extended accordingly.

[Brief description of drawings]

FIG. 1 is a top view of an electromagnetic contactor having an internal structure according to an embodiment of the present invention.

FIG. 2 is a side sectional view of the electromagnetic contactor taken along the line AA of FIG.

3A and 3B are views showing an embodiment of the base structure according to the present invention, wherein FIG. 3A is a perspective view showing the base structure according to the first embodiment, and FIG. The main part plan view, the same figure (c) is a main part plan view showing the main part of the base structure different from that in the same figure (b)

FIG. 4 is a top view of a conventional electromagnetic contactor having an internal structure.

5 is a side sectional view of the electromagnetic contactor taken along the line BB of FIG.

FIG. 6 is an exploded perspective view showing a conventional configuration example of a main part of an electromagnetic contactor targeted by the present invention.

[Explanation of symbols]

 1 main body case 2 base 2c guide surface 3a coil winding frame 5 fixed iron core 6 movable iron core 7 support 9 main fixed contact 10 main movable contact 14 support 19 insulating cover 20 base 20b long hole 20c guide surface

Claims (3)

[Claims] 1. Between a plate-shaped base fixed to the open end surface of the main body case so as to close the open end surface, and a coil winding frame of a main movable contact driving electromagnet housed in the main body case. , A plate-shaped base of the fixed iron core whose bottom surface covers an appropriate range of the plate-shaped base side of the fixed core of the electromagnet and is guided by a guide surface formed on the plate-shaped base in contact with the end face of the plate-shaped base of the fixed iron core. In an electromagnetic contactor in which an insulating cover for positioning above is arranged, and the end surface of the fixed iron core on the plate-shaped base side is pressed against the plate-shaped base by the spring force via the bottom surface of the insulating cover, a plurality of plate-shaped bases are provided. An electromagnetic contactor characterized in that a hole is formed to weaken the rigidity of the base surface against pressure from the fixed iron core side. 2. The electromagnetic contactor according to claim 1, wherein an end surface of the fixed iron core on the plate-shaped base side is formed in a square shape, and a plurality of holes formed in the plate-shaped base are fixed iron core end surfaces. 2. A magnetic contactor characterized in that it is a long hole in the longitudinal direction of the end face of the fixed core, which is formed in a plurality of rows in a single row or in a plurality of rows in the longitudinal direction. 3. The electromagnetic contactor according to claim 1 or 2, wherein the surface of the bottom surface of the insulating cover on the side of the plate-shaped base is
An electromagnetic contactor characterized in that a plurality of protrusions for pressing a thick portion between respective holes formed in a plate-shaped base are formed.