JP7593263B2 - Electromagnetic Contactor - Google Patents

Description

The present invention relates to an electromagnetic contactor that opens and closes a current path.

A known example of a conventional electromagnetic contactor is shown in Patent Document 1. The electromagnetic contactor of Patent Document 1 includes a contact mechanism that opens and closes a current path, a contact case that houses the contact mechanism, and an electromagnetic device that drives the movable contacts of the contact mechanism. The contact mechanism includes a pair of fixed contacts having fixed contacts, a movable contactor having a pair of movable contacts that can be brought into and out of contact with the fixed contacts of the pair of fixed contacts, an insulating holder made of a resin material that houses the pair of fixed contacts and the movable contacts, and a pair of arc-extinguishing permanent magnets that extend the arc generated between the pair of fixed contacts and the pair of movable contacts.

In the electromagnetic contactor of Patent Document 1, when an arc occurs between a pair of fixed contacts and a pair of movable contacts, the magnetic flux of the arc-extinguishing permanent magnet crosses the arc, causing the arc to be stretched within the contact case by the Lorentz force acting according to Fleming's left-hand rule, and the arc is extinguished.

JP 2021-44211 A

Incidentally, in the electromagnetic contactor of Patent Document 1, if the internal volume of the contact case housing the pair of fixed contacts and movable contact is small, the pressure and temperature inside the contact case rise when an arc occurs, affecting the arc extinguishing performance.
In addition, when the temperature of the pair of fixed contacts and the movable contact rises due to the occurrence of an arc, the fixed contacts and the movable contacts may melt and generate a large amount of metal vapor. In the device of Patent Document 1, metal vapor fills the vicinity of the arc that occurs between the fixed contacts and the movable contacts, which may cause a decrease in arc-extinguishing performance or a deterioration in the insulating performance of the pair of fixed contacts and the movable contacts, resulting in re-ignition.

The present invention aims to provide an electromagnetic contactor that suppresses pressure and temperature rises inside the case by expanding the internal volume of the case that houses the contact mechanism, and that has arc-extinguishing performance and prevents re-ignition of the arc even if a large amount of metal vapor is generated.

In order to achieve the above object, an electromagnetic contactor according to one embodiment of the present invention comprises a contact mechanism that opens and closes a current path, an electromagnet unit that drives a movable contact of the contact mechanism, and a storage case in which the contact mechanism and the electromagnet unit are disposed. The contact mechanism includes a first and second fixed contactor having a first and second fixed contact, a movable contactor provided at both ends in the longitudinal direction with first and second movable contacts that can be brought into and out of contact with the first and second fixed contacts, an insulating holder disposed inside the storage case and storing the first and second fixed contactor and the movable contactor, first and second arc extinguishing spaces surrounded by the inner wall of the storage case and the insulating holder and provided on one and the other longitudinal sides of the movable contactor, a pair of arc extinguishing permanent magnets arranged opposite each other to extend the first arc generated between the first fixed contactor and the first movable contact to the first arc extinguishing space and the second arc generated between the second fixed contactor and the second movable contact to the second arc extinguishing space, and a pair of communication spaces formed by the inner wall of the storage case and the insulating holder, which communicate the first and second arc extinguishing spaces with the space in which the electromagnet unit is stored.

The electromagnetic contactor of the present invention can suppress pressure and temperature rises inside the case by expanding the internal volume of the case that houses the contact mechanism, and can also provide arc extinguishing performance and prevent re-ignition of the arc even if a large amount of metal vapor is generated.

1 is a cross-sectional view of an electromagnetic contactor according to an embodiment of the present invention. 1 is a diagram showing a state in which an insulating holder constituting an electromagnetic contactor holds an arc-extinguishing permanent magnet and a magnetic pole plate. FIG. FIG. 4 is a cross-sectional view showing the structure of a contact mechanism. 1 is a diagram showing a state in which an arc is generated between a pair of fixed contacts of a pair of fixed contacts and a pair of movable contacts of a movable contact that separates these fixed contacts.

Next, an embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are given the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between thickness and planar dimensions, the thickness ratio of each layer, etc., differ from the actual ones. Therefore, the specific thickness and dimensions should be determined with reference to the following explanation. In addition, it goes without saying that the drawings include parts with different dimensional relationships and ratios.

In addition, the embodiments shown below are merely examples of devices and methods for embodying the technical idea of the present invention, and the technical idea of the present invention does not specify the materials, shapes, structures, arrangements, etc. of the components to those described below. The technical idea of the present invention can be modified in various ways within the technical scope defined by the claims.
In addition, terms indicating directions such as "upper,""lower,""left,""right,""front,""rear,""longitudinaldirection," and "shortitudinal direction" used in the following description are used with reference to the directions in the attached drawings.

An electromagnetic contactor according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG.
As shown in FIG. 1, an electromagnetic contactor 1 of this embodiment includes a contact mechanism 2 and an electromagnet unit 3 that drives a movable contact of the contact mechanism 2, which will be described later.
The contact mechanism 2 and the electromagnet unit 3 are stored in a sealed state in the same space within a storage case 6. The storage case 6 is composed of a resin upper case 4 and a resin lower case 5 joined to the upper case 4. Arc extinguishing gas is sealed into the storage case 6 through a gas inlet pipe 7. After the arc extinguishing gas is sealed inside the storage case 6, the gas inlet pipe 7 is cut midway and the opening is closed. The upper case 4 of the storage case 6 is provided with an attachment portion 8 for attachment to another member.

As shown in Figure 1, the contact mechanism 2 comprises a pair of fixed contacts 11, 12 (hereinafter referred to as the first fixed contact 11 and the second fixed contact 12) fixed to the upper case 4 by insert molding, and a movable contact 13 that can be brought into contact with and separated from the first fixed contact 11 and the second fixed contact 12.
The first fixed contact 11 and the second fixed contact 12 are made of a conductive metal material and fixed at a predetermined distance in the left-right direction to the upper case 4. A fixed contact 11a is formed on the lower end surface of the first fixed contact 11 on the left side, and a fixed contact 12a is formed on the lower end surface of the second fixed contact 12 on the right side.

The movable contact 13 is a conductive plate made of conductive metal and extends in the left-right direction. It is supported by a contact support 14, a contact spring 15, and a spring retainer 16 connected to a movable plunger 21 of the electromagnet unit 3 (described later). A movable contact 13a that contacts the fixed contact 11a of the first fixed contact 11 on the left side is formed on the upper surface of the left end side of the movable contact 13, and a movable contact 13b that contacts the fixed contact 12a of the second fixed contact 12 on the right side is formed on the upper surface of the right end side of the movable contact 13. The contact support 14 is connected to the movable plunger 21 via a connecting spring 23 attached to the upper end of the movable plunger 21, and the contact support 14 supports a pair of legs of the spring retainer 16, which has a top plate portion and a pair of legs extending downward from both ends of the top plate portion. The movable contact 13 is arranged to penetrate between the top plate of the spring retainer 16 and the contact support 14 in the left-right direction, and is constantly biased upward by the contact spring 15 arranged between the movable contact 13 and the contact support 14, and is clamped between the top plate of the spring retainer 16 and the contact spring 15, thereby supporting the movable contact 13.

As shown in FIG. 1, the electromagnet unit 3 includes a movable plunger 21, an armature 22, a connecting spring 23, a spool 24, an exciting coil 25, a yoke 31, an auxiliary yoke 32, a permanent magnet 33, and a return spring 34, and is disposed below the contact mechanism 2 inside the storage case 6.

The movable plunger 21 is a round shaft-shaped member made of a magnetic material and extending in the vertical direction. A connecting spring 23 is attached to the upper end of the movable plunger 21, and an armature 22 made of a disk-shaped magnetic material with a diameter larger than that of the movable plunger 21 is fixed to the lower end of the movable plunger 21. The contact support 14 is connected to the movable plunger 21 via the connecting spring 23, and moves upward as the movable plunger 21 moves upward, and moves downward as the movable plunger 21 moves downward. The movable contact 13 moves upward as the contact support 14 moves upward, and moves downward as the contact support 14 moves downward. A cylindrical sliding collar 26 is disposed on the lower side of the outer periphery of the movable plunger 21, and a cylindrical plunger ring 27 is disposed on the upper side.

The yoke 31 has a left yoke half 31a and a right yoke half 31b which have a symmetrical shape, and the upward movement of the movable plunger 21 is regulated by the armature 22 abutting against the lower surfaces of the left yoke half 31a and the right yoke half 31b of the yoke 31, and the downward movement of the movable plunger 21 is regulated by the armature 22 abutting against the upper surface of the auxiliary yoke 32.
The spool 24 is integrally formed from insulating synthetic resin, and includes a cylindrical body 24a that surrounds the outer periphery of the movable plunger 21 and extends in the vertical direction, an upper flange 24b provided at the upper end of the body 24a, and a lower flange 24c provided at the lower end of the body 24a. An excitation coil 25 that drives the movable plunger 21 is wound around the outer periphery of the body 24a of the spool 24. The excitation coil 25 is electrically connected to a terminal 36.

The permanent magnet 33 is an annular member, and is disposed below the left yoke half 31a and the right yoke half 31b of the yoke 31 and around the armature 22 of the movable plunger 21. An annular plate-shaped auxiliary yoke 32 made of a magnetic material is disposed below the permanent magnet 33. The permanent magnet 33 is attached to the lower surfaces of the lower plate portion 31ac of the left yoke half 31a and the lower plate portion 31bc of the right yoke half 31b, and the auxiliary yoke 32 is disposed in a state of being attached to the lower surface of the permanent magnet 33.
The return spring 34 is installed so as to surround the movable plunger 21 between the lower end surface of the sliding collar 26 and the armature 22 fixed to the movable plunger 21, and separates the movable contact 13 from the first fixed contact 11 and the second fixed contact 12 when the excited state of the excitation coil 25 is released.
Here, the contact mechanism 2 (the first fixed contact 11, the second fixed contact 12 and the movable contact 13) is housed in an insulating holder 40 made of synthetic resin as shown in FIG.

2, the insulating holder 40 is a member having a substantially identical rectangular parallelepiped shape, a pair of magnet storage sections 41, 42 arranged parallel to each other with their inner walls 41a, 42a facing each other, and a pair of connecting members 44a, 44b connecting the lower sides of both ends in the longitudinal direction of the pair of storage spaces 45, 46 with a contactor storage space 43 provided between the pair of magnet storage sections 41, 42. Here, the pair of connecting members 44a, 44b are formed in an arc shape that protrudes toward the magnet storage sections 41, 42, and are arranged so as to overlap the upper arc portions of the left yoke half 31a and the right yoke half 31b of the electromagnet unit 3 as shown in FIG. 1.

One magnet storage section 41 has side walls 41b, 41c extending in an orthogonal direction from both longitudinal ends of the inner wall 41a to the other magnet storage section 42, and a storage space 45 is formed in the space surrounded by these inner walls 41a and side walls 41b, 41c. The other magnet storage section 42 also has side walls 42b, 42c extending in an orthogonal direction from both longitudinal ends of the inner wall 42a to the one magnet storage section 41, and a storage space 46 is formed in the space surrounded by these inner walls 42a and side walls 42b, 42c.

2, the storage space 45 of one magnet storage section 41 stores a rectangular parallelepiped-shaped arc extinguishing permanent magnet 47 in contact with the inner wall 41a, and a magnetic pole plate 48 with the same back surface shape as the arc extinguishing permanent magnet 47 in contact with the back surface of the arc extinguishing permanent magnet 47 on the opposite side of the inner wall 41a. The storage space 46 of the other magnet storage section 42 stores a rectangular parallelepiped-shaped arc extinguishing permanent magnet 49 in contact with the inner wall 42a, and a magnetic pole plate 50 with the same back surface shape as the arc extinguishing permanent magnet 49 in contact with the back surface of the arc extinguishing permanent magnet 49 on the opposite side of the inner wall 42a. The magnetic pole surface of the arc extinguishing permanent magnet 47 that contacts the inner wall 41a is the S pole, and the magnetic pole surface of the arc extinguishing permanent magnet 49 that contacts the inner wall 42a is the N pole. Here, as shown in Figures 2 and 3, the magnetic pole plate 50 is stored in the storage space 46 by engaging with the inside of a pair of storage protrusions 51 formed on the outer edges of the side walls 42b and 42c and protruding in directions toward each other. Also, as shown in Figure 3, the magnetic pole plate 38 stored in the storage space 35 is stored in the storage space 45 by engaging with the inside of a pair of storage protrusions 52 formed on the outer edges of the side walls 41b and 41c and protruding in directions toward each other.

Figure 3 shows the insulating holder 40 placed inside the upper case 4. The contact mechanism 2 (first fixed contact 11, second fixed contact 12, and movable contact 13) is placed in the contact storage space 43 between the magnet storage sections 41 and 42 of the insulating holder 40.

If the fixed contact 12a of the second fixed contactor 12 and the movable contact 13b of the movable contactor 13 that comes into contact with and separates from the fixed contact 12a are referred to as the contact portion 55a, and the fixed contact 11a of the first fixed contactor 11 and the movable contact 13b of the movable contactor 13 that comes into contact with and separates from the fixed contact 11a are referred to as the contact portion 55b, the magnetic flux (dashed arrow in FIG. 3) that flows from the arc-extinguishing permanent magnet 49 stored in the magnet storage portion 42 to the arc-extinguishing permanent magnet 47 stored in the magnet storage portion 41 crosses the contact portions 65a and 55b. The area to the right of the contact portion 55a, and the space surrounded by the right inner wall of the upper case 4 and the magnet storage portions 41 and 42, is the first arc-extinguishing space S1. Additionally, the area to the left of the contact portion 55b and surrounded by the left inner wall of the upper case 4 and the magnet storage portions 41 and 42 is the second arc extinguishing space S2.

As shown in FIG. 3, communication spaces 56a, 56b are formed at a position surrounded by the magnet storage sections 41, 42 and pair of connecting members 44a, 44b of the insulating holder 40 and the inner wall of the upper case 4, which connect the space in which the electromagnet unit 3 is housed to the first and second arc extinguishing spaces S1, S2.

Next, the operation of the electromagnetic contactor 1 of this embodiment will be described with reference to FIG.
In the electromagnetic contactor 1 of this embodiment, a negative (−) terminal is connected to the first fixed contact 11 , and a positive (+) terminal is connected to the second fixed contact 12 .
Now, assume that the exciting coil 25 of the electromagnet unit 3 is in a non-excited state, and the electromagnet unit 3 is in a released state in which it is not generating an exciting force that moves the movable plunger 21 upward. In this released state, the movable plunger 21 is urged downward by the return spring 34, and the armature 22 is attracted to the auxiliary yoke 32 by the action of the permanent magnet 33. Therefore, the movable contactor 13 connected to the movable plunger 21 is spaced downward by a predetermined distance from the first fixed contactor 11 and the second fixed contactor 12. Therefore, the current path between the first fixed contactor 11 and the second fixed contactor 12 is in an interrupted state, and the contact portions 55a, 55b of the contact mechanism 2 are in an open state (open state of the contact mechanism 2).

When electricity is applied to the excitation coil 25 of the electromagnet unit 3 from the open state of this contact mechanism 2, an excitation force is generated in the electromagnet unit 3, which pushes the movable plunger 21 upward against the attraction force of the permanent magnet 33 to the auxiliary yoke 32 and the biasing force of the return spring 34, and the armature 22 is attracted to the undersides of the lower plate portion ac of the left yoke half 31a and the lower plate portion bc of the right yoke half 31b of the yoke 31.
In this way, as the movable plunger 21 moves upward, the movable contactor 13 connected to the movable plunger 21 also moves upward, and both contacts 13a, 13b of the movable contactor 13 come into contact with the fixed contact 11a of the first fixed contactor 11 and the fixed contact 12a of the second fixed contactor 12 with the contact pressure of the contact spring 15, and the contact portions 55a, 55b of the contact mechanism 2 are placed in a closed state (closed state of the contact mechanism 2).

When the contact mechanism 2 is in the closed state and the current flow to the excitation coil 25 of the electromagnet unit 3 is stopped, the excitation force that moves the movable plunger 21 upward in the electromagnet unit 3 is eliminated, and the movable plunger 21 moves downward due to the biasing force of the return spring 34, and the armature 22 is attracted to the auxiliary yoke 32 by the action of the permanent magnet 33.
When the movable plunger 21 moves downward, the movable contact 13 connected to the movable plunger 21 moves downward away from the first fixed contact 11 and the second fixed contact 12, thereby starting the opening state.

When the contact mechanism 2 starts to open in this manner, a first arc is generated between the contact portions 55a and a second arc is generated between the contact portions 55b of the contact mechanism 2, and a current flow state is continued by these first and second arcs. The current direction of the first arc is from the fixed contact 12a to the movable contact 13b, and the current direction of the second arc is from the movable contact 13a to the fixed contact 11a.
At this time, a magnetic flux emerging from the N pole of the arc-extinguishing permanent magnet 49 and flowing to the S pole of the arc-extinguishing permanent magnet 47 crosses the first arc and the second arc.

From the relationship between the current flow and magnetic flux of the first arc, a Lorentz force F1 is generated in the direction toward the first arc extinguishing space S1 according to Fleming's left-hand rule. Also, from the relationship between the current flow and magnetic flux of the second arc, a Lorentz force F2 is generated in the direction toward the second arc extinguishing space S2 according to Fleming's left-hand rule.
The direction of the current flow between the contact parts 55a changes left and right as the arcing point of the first arc moves to the right end of the movable contact 13 and the fixed contact 12. When the direction of the current flow between the contact parts 55a changes left and right, the direction in which the Lorentz force F1 is generated changes to the downward direction toward the electromagnet unit 3, and the first arc is largely extended into the first arc extinguishing space S1 and is cooled by contact with the arc extinguishing gas sealed in the storage case 6.

In addition, as the arcing point of the second arc moves to the left end of the movable contact 13 and the fixed contact 11, the direction of the current flow between the contact parts 55b changes left and right. When the direction of the current flow between the contact parts 55b changes left and right, the direction in which the Lorentz force F2 is generated changes downward toward the electromagnet unit 3, and the second arc is extended significantly into the second arc extinguishing space S1, where it comes into contact with the arc extinguishing gas sealed in the storage case 6 and is cooled.

On the other hand, in the contact portion 55a, the fixed contact 12a and the movable contact 13b melt due to the temperature rise of the first arc, generating metal vapor, and in the contact portion 55b, the fixed contact 12a and the movable contact 13b melt due to the temperature rise of the second arc, generating metal vapor.
The metal vapor generated at the contact portions 55a, 55b is dispersed into the first and second arc extinguishing spaces S1, S, and passes through the communication spaces 56a, 56b to diffuse into the accommodation space of the electromagnet unit 3.

Here, the connecting members 44a, 44b of the insulating holder 40, which form the communication space 56a, 56b with the inner wall of the upper case 4, are formed in an arc shape protruding toward the first and second arc extinguishing spaces S1, 2. As a result, the communication space 56a becomes gradually narrower from the first arc extinguishing space S1 toward the storage space of the electromagnet unit 3, and the communication space 56b becomes gradually narrower from the second arc extinguishing space S2 toward the storage space of the electromagnet unit 3. Therefore, the metal vapor filling the first and second arc extinguishing spaces S1, S passes through the gradually narrower communication spaces 56a, 56b at an increased speed and is diffused into the storage space of the electromagnet unit 3. Therefore, the first and second arc extinguishing spaces S1, S are prevented from being filled with metal vapor. The metal vapor flowing into the storage space of the electromagnet unit 3 is cooled by contacting a part of the yoke 31, and the pressure and temperature inside the storage case 6 are reduced.

Next, the effects of the electromagnetic contactor 1 of this embodiment will be described.
When the first and second arcs are generated at the contact portions 55a and 55b of the contact mechanism 2 due to the opening start state of the contact mechanism 2, the magnetic flux flowing between the arc-extinguishing permanent magnets 47 and 49 crosses the first and second arcs. Then, as the arcing point of the first arc moves to the right end of the movable contact 13 and the fixed contact 12, the direction of the current flow between the contact portion 55a changes in the left-right direction, and the direction of the Lorentz force F1 changes downward toward the electromagnet unit 3. Also, as the arcing point of the second arc moves to the left end of the movable contact 13 and the fixed contact 11, the direction of the current flow between the contact portion 55b changes in the left-right direction, and the direction of the Lorentz force F2 changes downward toward the electromagnet unit 3. As a result, the first and second arcs are largely extended into the first arc-extinguishing spaces S1 and S3, improving the interruption performance.

In addition, the metal vapor generated at the contact portions 55a and 55b is dispersed into the first and second arc extinguishing spaces S1 and S, and passes through the communication spaces 56a and 56b to diffuse into the accommodation space of the electromagnet unit 3. At this time, the communication space 56a is gradually narrowed from the first arc extinguishing space S1 to the accommodation space of the electromagnet unit 3, and the communication space 56b is gradually narrowed from the second arc extinguishing space S2 to the accommodation space of the electromagnet unit 3, so that the metal vapor filling the first and second arc extinguishing spaces S1 and S passes through the communication spaces 56a and 56b at an increased speed and diffuses into the accommodation space of the electromagnet unit 3. Therefore, the first and second arc extinguishing spaces S1 and S are prevented from being filled with metal vapor, and the metal vapor that flows into the storage space of the electromagnet unit 3 is cooled by contacting a part of the yoke 31, which has a high thermal conductivity, and changes phase to liquid or solid, and the pressure and temperature inside the storage case 6 decrease, preventing a decrease in the extinguishing performance and preventing the re-ignition of the first and second arcs.

In addition, in this embodiment, the magnetic pole plate 48 is arranged only on the back surface of the arc extinguishing permanent magnet 47, and the magnetic pole plate 50 is arranged only on the back surface of the arc extinguishing permanent magnet 49. Normally, it is common to arrange magnetic pole members that straddle the arc extinguishing permanent magnets 47, 49 so as to form a magnetic loop between the arc extinguishing permanent magnets 47, 49. However, if the arc extinguishing permanent magnets 47, 49 with a high surface magnetic flux density are selected to greatly extend the first and second arcs, there is a risk that the magnetic resistance will become high due to magnetic saturation in the magnetic pole members that form the magnetic loop. Therefore, in this embodiment, even if the arc extinguishing permanent magnets 47, 49 with a high surface magnetic flux density are selected, the problem of magnetic saturation caused by using the magnetic pole members of the magnetic loop can be solved. In addition, since no magnetic pole members that straddle the arc extinguishing permanent magnets 47, 49 are used, large first and second arc extinguishing spaces S1, S can be set.

REFERENCE SIGNS LIST 1 Electromagnetic contactor 2 Contact mechanism 3 Electromagnet unit 4 Upper case 5 Lower case 6 Storage case 7 Gas inlet pipe 8 Mounting portion 11 First fixed contact 11a Fixed contact 12 Second fixed contact 12a Fixed contact 13 Movable contact 13a Movable contact 13b Movable contact 14 Contact support 15 Contact spring 16 Spring retainer 23 Connecting spring 21 Movable plunger 22 Armature 23 Connecting spring 24 Spool 24a Body portion 24b Upper flange portion 24c Lower flange portion 25 Excitation coil 26 Sliding collar 27 Plunger ring 31 Yoke 31a Left yoke half 31b Right yoke half 32 Auxiliary yoke 33 Permanent magnet 34 Return spring 36 Terminal 36
Reference Signs List 40: Insulating holder 41, 42: Magnet storage section 41a, 42a: Inner wall 41b, 41c: Side wall 42b, 42c: Side wall 43: Contact storage space 44a, 44b: Connecting member 45, 46: Storage space 47, 49: Arc-extinguishing permanent magnet 48, 50: Magnetic pole plate 51, 52: Storage protrusion 55a, 55b: Contact portion 56a, 56b: Communication space S1: First arc-extinguishing space S2: Second arc-extinguishing space

Claims (5)

a contact mechanism that opens and closes a current path, an electromagnet unit that drives a movable contact of the contact mechanism, and a storage case in which the contact mechanism and the electromagnet unit are disposed,
The contact mechanism includes:
a first and second fixed contactor having a first and second fixed contact;
a movable contactor including first and second movable contacts at both ends in a longitudinal direction thereof, the first and second movable contacts being movable toward and away from the first and second fixed contacts;
an insulating holder disposed inside the housing case and housing the first and second fixed contacts and the movable contact;
a first arc extinguishing space and a second arc extinguishing space, the first arc extinguishing space and the second arc extinguishing space being surrounded by an inner wall of the housing case and the insulating holder and being provided on one side and the other side in a longitudinal direction of the movable contact;
a pair of arc-extinguishing permanent magnets arranged opposite to each other, the pair extending a first arc generated between the first fixed contact and the first movable contact into the first arc-extinguishing space, and the pair extending a second arc generated between the second fixed contact and the second movable contact into the second arc-extinguishing space;
a pair of communication spaces formed by an inner wall of the storage case and the insulating holder, the communication spaces connecting the first and second arc extinguishing spaces with a space in which the electromagnet unit is stored;
An electromagnetic contactor comprising: the insulating holder includes a pair of magnet storage sections that store the pair of arc-extinguishing permanent magnets, and a pair of connecting members that are arranged on the electromagnet unit side and connect the pair of magnet storage sections that are arranged apart from each other with a contact storage space therebetween that stores the first and second fixed contacts and the movable contact,
2. The electromagnetic contactor according to claim 1, wherein the pair of communication spaces are provided between the pair of connecting members and an inner wall of the storage case. The electromagnetic contactor according to claim 1 or 2, characterized in that the surfaces of the pair of connecting members facing the first and second arc extinguishing spaces are formed into an arcuate surface shape that protrudes toward the first and second arc extinguishing spaces. An electromagnetic contactor according to claim 2 or 3, characterized in that the pair of magnet storage sections of each of the insulating holders stores magnetic pole plates of the same shape as the arc-extinguishing permanent magnets, stacked on the back surface of the arc-extinguishing permanent magnets. An electromagnetic contactor according to any one of claims 1 to 4, characterized in that the storage case is filled with arc-extinguishing gas.

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