JPS6028101Y2 - electromagnetic contactor electromagnet - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a clapper-type (or hinge-type) electromagnet that is mainly used as an electromagnet for driving a movable contact of an electromagnetic contactor.

Generally, the cross-sectional area of the core is determined from the magnetic flux and magnetic flux density, and the cross-sectional area of the coil is determined in order to obtain the magnetomotive force necessary to generate a predetermined attractive force. Therefore, the window dimensions of the core are determined. The overall shape of the core is determined, but especially in the case of a laminated core, in order to avoid twisting in the cross-sectional direction, that is, twisting, it is necessary to make the vertical and horizontal widths of the cross-section of the core magnetic path sufficiently large to increase the strength. be.

On the other hand, the inertia of the movable part for opening and closing of a magnetic contactor must be as small as possible, and the impact and recoil at the time of closing must be reduced to suppress the recoil phenomenon of the movable contactor. However, the movable core is equipped with means for connecting with the movable part, means for engaging with the fixed core, caulking rivets for the laminated plates, etc., and from the viewpoint of strength, the cross-sectional area must be reduced as much as possible. There are also restrictions on reducing the size of the inertia, and it is not easy to reduce the inertia.

Therefore, in this type of conventional device, a large amount of excitation energy is required to start the movable core during coil excitation, and a large impact force is exerted when the cores collide, so the core is likely to move. It had the disadvantage of being unstable.

In view of these points, the present invention provides an electromagnet for an electromagnetic contactor that reduces the rotational moment of the movable core while maintaining mechanical strength by providing a hole in the corner far from the rotation axis of the movable core. be.

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

FIG. 1 shows a front view of the embodiment. In the figure, the movable core 1 and the fixed core 2 are each made of so-called electrical iron plates laminated and caulked, and the sheep part is a semicircular shape formed on the movable core 1. The recess 1a and the semicircular recess 2a formed in the fixed core 2 are made to face each other, a shaft pin 3 is inserted between them, and the movable core 1 is rotatably supported around the shaft pin 3. .

Furthermore, a six 1b is provided at the upper corner of the movable core 1.

Reference numeral 4 denotes a round ring provided on the end face of the armature portion of the fixed iron core 2.

5 is an excitation coil, and 6 is a spacer attached to the fixed iron core 2 to prevent magnetic residue of the iron core.

In the electromagnet with the above configuration, the moment of inertia L around the shaft pin 3 when the movable core 1 does not have the six 1b, the moment of inertia I around the shaft pin 3 when the movable core 1 has the six 1b, the movable core Assuming the moment of inertia I2 around the shaft pin 3 of the part corresponding to 61b in 1, then: -〇, 112 11=Io-I2 In other words, by making the hole 1b, the moment of inertia can be reduced by that amount. Can be done.

If the mass of the part corresponding to this hole 1b is m, and the distance between its center of gravity and the shaft pin 3 is r, then I2 = mr2 Therefore, the larger the mass m and the distance r, the larger the moment of inertia I2, and the movable part of the hole 1b. The moment of inertia of the iron core 1 can be reduced.

The outer shape of the movable core 1 is limited in order to miniaturize the electromagnetic contactor, and the core width is also limited in terms of strength. Therefore, the shape of the movable core 1 is narrow in the core width direction and is an elongated ellipse that extends along the core length direction. Or, with a rectangular or similar hole, the center of gravity is as far away from the shaft pin 3 as possible, for example, by positioning it far from the shaft pin 3, or by making the shape of the 61b wider at the part far from the shaft pin 3. It is possible to increase the effect by doing things like this.

Further, in order to prevent the cross-sectional area of the core from becoming narrower due to the sixth 1b and the magnetic resistance from increasing, the hole should be located at a corner where less magnetic flux flows, avoiding the effective magnetic path.

2 and 3 show an example of an electromagnetic contactor using the electromagnet of the present invention, with FIG. 2 showing the open state and FIG. 3 showing the closed state.

In the figure, the lower surface 2b of the fixed core 2 is the molded case 7.
A buffer leaf spring 8 is inserted between the right surface 2c of the fixed iron core 2 and the right inner wall surface 7b of the molded case 7.

Further, a recess 1c is provided below the movable iron core 1, and a repulsion spring 9 is inserted between it and the left inner wall surface 7c of the molded case 7.

This repulsion spring 9 acts to rotate the movable iron core 1 around the shaft pin 3 in a counterclockwise direction.

That is, a biasing force is applied to tilt the movable iron core 1 toward the open side.

Further, an operating projection 1d is provided above the movable core 1, and is fitted into the 0-shape 411b of the protruding retaining portion 11a provided on the movable frame 11 attached to the contact portion 10.

A movable contact 12 is movably attached to the movable frame 11, and faces a fixed contact 13 fixed to the molded case 7, so that the movable contact 12 can be moved toward and away from the movable frame 11 as it moves left and right.

Next, the operation of the device configured as described above will be explained.

When the excitation coil 5 is not energized, the movable core 1 is tilted toward the open side by the biasing force of the repulsion spring 9, as shown in FIG. Since the movable frame 11 is moved leftward in the drawing by playing, the contacts are kept open.

Next, when the excitation coil 5 is energized, the movable core 1 overcomes the biasing force of the repulsion spring 9 due to the magnetic attraction force generated in the gap between the armature surfaces of the fixed core 2 and the movable core 1, as shown in FIG. It is attracted using the shaft pin 3 as the shaft.

Due to this suction, the movable frame 11 with which the actuating projection 1d is loosely moved moves to the right to close the contact.

In this way, the movable core 1 rotates about the shaft pin 3, but in this case, the impact force when the movable core 1 is inserted and attracted is transmitted to the movable frame 11, and the movable contact 12 comes into contact with the fixed contact 13. At that moment, the shock vibration causes recoil between the contacts, causing abnormal wear on the contacts.

In order to reduce the impact force applied to the movable core 1, the moment of inertia of the movable core 1 around the shaft pin 3 must be reduced.

This purpose is distantly achieved by providing the movable iron core 1 with the 61b.

When providing the 61b, consideration should be given so as not to adversely affect the mechanical strength, magnetic flux density, etc., as described above.

The effect of reducing the moment of inertia depending on the shape and position of the six 1b will be explained using a specific example.

In FIG. 4, a indicates a basic movable iron core without holes.

The hole b is provided in the upper corner of the movable core as far away from the axis as possible, and the moment of inertia is reduced compared to the figure a.

In C, the center of gravity of the hole is made as far away from the axis as possible by widening the hole toward the end, and the moment of inertia is further reduced than in Fig. B.

d is a hole further added to a portion farther from the axis.

This additional hole can also be used as a separate hole from the original hole.
Alternatively, the holes may be formed as a continuous hole.

In this case as well, the moment of inertia is further reduced than in Figure b.

Example e is a bad example in which the hole is located close to the axis, but in this position there is no effect of reducing the moment of inertia and the operating characteristics are not improved.

Furthermore, since the magnetic flux density around the hole becomes extremely high, electromagnet loss increases, resulting in an inefficient electromagnet.

As described above, the present invention reduces the rotational moment of the movable core by providing a hole in the corner far from the rotation axis of the movable core, reduces the impact when the cores collide with each other, and eliminates the movement of the core. By doing so, it is possible to obtain an electromagnet for an electromagnetic contactor that operates stably.

[Brief explanation of the drawing]

Figure 1 is a front view showing an embodiment of the present invention, Figures 2 and 3 are
The figure is a sectional view showing an embodiment of an electromagnetic contactor using the electromagnet of the present invention, and FIG. 4 is an explanatory view of a movable iron core. 1...Movable iron core, 1b...hole, 2...
... Fixed iron core, 3 ... Axis pin.

Claims (1)

[Scope of utility model registration request] In an electromagnet consisting of a fixed core and a movable core, with one of the two opposing magnetic pole surfaces serving as a hinge portion and the other serving as an armature, a hole is provided in a corner portion far from the rotation axis of the movable core. An electromagnet for an electromagnetic contactor featuring: