JP2016136477A - Electromagnetic tripping device and circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tripping device and a circuit breaker in which operation time in a motor-start current area is slower but the same as the conventional in a low overcurrent area and a short-circuit current area.SOLUTION: The electromagnetic tripping device has a magnetic circuit constituted of a temperature-sensitive magnetic and is arranged so that the operation time is delayed in a motor start current area by attracting a plunger toward the bottom side of a cylinder.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electromagnetic trip device and a circuit breaker.

  Conventionally, there is a circuit breaker using an electromagnet with an oil dashpot as a time-delaying element. (For example, see Patent Document 1).

  That is, when an overcurrent flows through the electromagnetic coil, the plunger, which is a magnetic body, overcomes the spring force of the braking spring (corresponding to “spring 53” in Patent Document 1) and moves toward the pole head. When approaching the pole head, the amount of magnetic flux of the plunger increases, and an armature (corresponding to “operation bar 62a” in Patent Document 1) is strongly attracted to the pole head side. The amateur then rotates and unlatches the circuit breaker. The circuit breaker trips when the latch is released.

  In the electromagnet with an oil dashpot, the inverse time characteristic is obtained by using the braking of the plunger by the viscous resistance of the braking oil in the cylinder. On the other hand, when a very large current flows, the magnetic flux increases, so that even if the plunger hardly moves, the amateur is instantaneously attracted and the circuit breaker trips.

JP 2013-145543 A

  Compared with conventional motors, recent top runner motors have a larger starting current. Therefore, the current circuit breaker may malfunction at start-up. Therefore, it is necessary to delay the operation time in the motor starting current region. That is, the operating time in the starting current region (about 6 to 8 times the rated current) is made slower than the conventional one, and the low overcurrent region (about 1.25 to 2 times the rated current) and the short circuit current It is necessary to make the operation time in the region (about 15 times or more of the rated current) equivalent to the conventional one.

  The present invention has been made in view of the above-described reasons, and the operation time in the starting current region is slower than the conventional one, and the operation time in the low overcurrent region and the short-circuit current region is equivalent to the conventional one. An object is to provide a trip device and a circuit breaker.

An electromagnetic trip device according to the present invention includes a cylinder made of a non-magnetic material having a bottomed cylindrical shape, a plunger made of a magnetic material, and a plunger provided in the cylinder, and the plunger on the rear end side serving as the bottom of the cylinder. A brake spring that pushes toward the head, a pole head that is made of a magnetic material and seals the opening on the front end side of the cylinder, and an electromagnetic coil and a magnetic material that are provided so as to wind the cylinder, and is provided outside the electromagnetic coil. The yoke having a parallel piece arranged in parallel with the axial direction of the cylinder and a right-angle piece extending toward the cylinder; and a magnetic body, the yoke being configured so as to be rotatable toward the pole head. A permanent magnet, provided on the bottom side of the plunger, and directed toward the cylinder bottom side with respect to the plunger. And a temperature-sensitive magnetic body that is provided in the vicinity of the plunger and the attraction magnet and has a magnetic property that changes greatly in the vicinity of the Curie temperature, and the temperature-sensitive magnetic body increases in temperature. Thus, the magnetic attraction force is reduced when it becomes non-magnetic.

  A circuit breaker according to the present invention includes the above-described electromagnetic trip.

  The present invention provides an electromagnetic trip device and a circuit breaker in which the operation time in the starting current region is slower than the conventional one and the operation times in the low overcurrent region and the short-circuit current region are the same as the conventional one. it can.

1 is a configuration diagram of an electromagnetic tripping device according to Embodiment 1. FIG. It is a figure which shows magnetic flux when the temperature sensitive magnetic body 9 of the electromagnetic trip apparatus which concerns on Embodiment 1 turns into a nonmagnetic body. It is a block diagram of the electromagnetic trip apparatus which concerns on Embodiment 2. FIG. (A) is a figure which shows magnetic flux when the temperature sensitive magnetic body 9 is a magnetic body. (B) is a figure which shows magnetic flux when the temperature sensitive magnetic body 9 turns into a non-magnetic body. It is a block diagram of the electromagnetic tripping device concerning Embodiment 3. It is a block diagram of the electromagnetic tripping device concerning Embodiment 4. It is a block diagram when the electromagnetic trip apparatus which concerns on Embodiments 1-4 is mounted in a circuit breaker.

(Embodiment 1)
Hereinafter, the electromagnetic trip device 100 according to Embodiment 1 will be described with reference to FIGS. 1 and 2.
<Configuration>
FIG. 1 is a configuration diagram of an electromagnetic tripping device 100 according to the first embodiment. As shown in FIG. 1, the electromagnetic trip device 100 includes a cylinder 1 made of a cylindrical non-magnetic material having a bottom, a plunger 2 provided inside the cylinder 1, and pushes the plunger 2 toward the bottom of the cylinder 1. The brake spring 3, the pole head 4 that seals the cylinder 1, the electromagnetic coil 5 provided so as to wind the cylinder 1, the yoke 6 made of a substantially L-shaped magnetic body, and the pole head 4 side made of a magnetic body And an amateur 7 capable of rotating.

  The plunger 2 has a substantially axisymmetric shape with a substantially circular cross section, and includes a portion having a large diameter (a large diameter portion 2a) with which one end of the braking spring 3 contacts and a protruding portion 2b having a diameter smaller than the inner diameter of the braking spring 3. Become. The protruding portion 2b is configured to enter the inside of the braking spring 3.

  A pole head 4 is provided on the side opposite to the bottom of the cylinder 1, and the plunger 2 and the brake spring 3 are accommodated in a space surrounded by the cylinder 1 and the pole head 4. Normally, the space surrounded by the cylinder 1 and the pole head 4 is in a sealed state and filled with a liquid such as oil, but the present invention includes a configuration not filled with a liquid.

  The yoke 6 is made of a substantially L-shaped magnetic body, and has a parallel piece 6 a disposed parallel to the axis of the cylinder 1 and a right-angle piece 6 b extending in a direction perpendicular to the axis of the cylinder 1. The right-angle piece 6 b extends to the plunger 2 side and is connected to the cylinder 1. In the present invention, the yoke 6 may be disposed so as to form a magnetic path with the plunger 2 as will be described later, and is not necessarily fixed to the cylinder 1.

The electromagnetic coil 5 is provided to wind the cylinder 1 so as to be sandwiched between the plunger 2 and the yoke 6. The electromagnetic coil 5 is connected to the main electric circuit 11. In the first embodiment, the electromagnetic coil 5 and the main electric path 11 are integrally formed of the same member. In the present invention, the electromagnetic coil 5 and the main electric circuit 11 are separate members and may be electrically connected.

  The amateur 7 is usually made of a magnetic material. The amateur 7 is connected to the parallel piece 6a of the yoke 6 so as to be able to rotate toward the pole head 4 side.

  The attraction magnet 8 is made of a permanent magnet and is provided on the bottom side of the cylinder 1. The attracting magnet 8 is magnetized in a direction parallel to the axial direction of the plunger 2 (the direction indicated by the arrow in FIG. 1), and by attracting the plunger 2 magnetically, the cylinder 1 is attracted to the plunger 2. A magnetic attraction force in the direction toward the bottom side is applied.

  The temperature-sensitive magnetic body 9 is provided between the bottom of the cylinder 1 and the attracting magnet 8. The temperature-sensitive magnetic body 9 has a Curie temperature between the lower limit temperature T1 and the upper limit temperature T2 of the operating temperature, and its magnetic characteristics (permeability, magnetic flux density, coercive force, etc.) change suddenly near the Curie temperature. is there. That is, the temperature-sensitive magnetic body 9 has magnetic properties as a magnetic body when it is lower than the Curie temperature, and becomes a non-magnetic body when it is higher than the Curie temperature.

  As shown in FIG. 1, the temperature-sensitive magnetic body 9 is directly connected to the main electric circuit 11, and a current flowing through the main electric circuit flows through the temperature-sensitive magnetic body 9. In the present invention, the temperature-sensitive magnetic body 9 may be connected to the main electric circuit 11 via an insulating member such as a nonmetal. In the present invention, the temperature-sensitive magnetic body 9 is not necessarily connected to the main electric circuit 11. That is, there may be a gap between the temperature-sensitive magnetic body 9 and the main electrical path 11 or the electromagnetic coil 5, and the temperature-sensitive magnetic body 9 is heated by the heat generated when the main electrical path 11 or the electromagnetic coil 5 is energized. Thus, the structure by which the temperature-sensitive magnetic body 9 is arrange | positioned in the vicinity of the main electrical path 11 or the electromagnetic coil 5 may be sufficient.

The auxiliary yoke 10 is made of a magnetic material, and is provided on the opposite side of the temperature-sensitive magnetic material 9 with respect to the attracting magnet 8. The auxiliary yoke 10 is provided to increase the attractive force of the attractive magnet 8 acting on the plunger 2. In the present invention, the auxiliary yoke 10 may be configured without the auxiliary yoke.
<Operation>
Hereinafter, the operation of the electromagnetic trip device 100 according to the first embodiment when the current flowing through the electromagnetic coil 5 is in the low overcurrent region will be described with reference to FIGS. 1 and 2.

  When a current flows through the electromagnetic coil 5, a magnetic flux is formed. The magnetic flux passes through a magnetic path formed by the pole head 4, the armature 7, the yoke 6 and the plunger 2. As shown in FIG. 1, since a gap is formed between the pole head 4 and the protruding portion 2 b of the plunger 2, a magnetic attractive force acts between the pole head 4 and the plunger 2. That is, a force in the direction of moving toward the pole head 4 acts on the plunger 2.

  When the magnetic attractive force acting on the plunger 2 becomes larger than the force by which the braking spring 3 pushes the plunger 2, the plunger 2 starts to move toward the pole head 4 side. As the plunger 2 moves, the gap between the pole head 4 and the plunger 2 (projection 2b) becomes smaller. If the gap is reduced, the resistance of the magnetic circuit formed by the pole head 4, the armature 7, the yoke 6, and the plunger 2 is reduced, so that the magnetic flux is increased.

By increasing the magnetic flux, the magnetic attractive force acting on the plunger 2 is further increased, and the gap between the pole head 4 and the plunger 2 is further decreased. By repeating the above, the gap gradually decreases and the magnetic flux increases. In the case of the low overcurrent region, when the protrusion 2b of the plunger 2 reaches a position in contact with or close to the pole head 4, a large suction force toward the pole head 4 acts on the armature 7 and the armature 7 rotates. And adsorbed to the pole head 4 side. When the latch 50 (see FIG. 6) of the circuit breaker mechanism is pushed by the armature 7, the circuit breaker operates.

  Hereinafter, the operation of the electromagnetic trip device 100 according to the first embodiment when the current flowing through the electromagnetic coil 5 is in the starting current region will be described.

  When a current flows through the electromagnetic coil 5, a magnetic flux is formed. The magnetic flux passes through a magnetic path formed by the pole head 4, the armature 7, the yoke 6 and the plunger 2. Gaps are formed between the pole head 4 and the plunger 2 and between the armature 7 and the pole head 4, respectively. Therefore, when a current flows through the electromagnetic coil 5, a force in the direction of moving toward the pole head 4 acts on the plunger 2 and the armature 7 due to the magnetic attractive force.

  Compared to the low overcurrent region, in the starting current region, the current flowing through the electromagnetic coil 5 is large, so that a larger magnetic flux can be obtained. That is, when the gap between the pole head 4 and the plunger 2 is reduced to some extent, the armature 7 starts to move toward the pole head 4 side. In the case of the starting current region, when the gap between the pole head 4 and the plunger 2 is about 70% of the gap when there is no energization, the armature 7 has a latch 50 (see FIG. 6) of the circuit breaker mechanism. ) And the circuit breaker is activated.

  Hereinafter, the operation of the electromagnetic trip device 100 according to the first embodiment when the current flowing through the electromagnetic coil 5 is in the short-circuit current region will be described.

When the current flowing through the electromagnetic coil 5 is in the short-circuit current region, a large magnetic flux can be obtained even if the gap between the pole head 4 and the plunger 2 is not small, and the armature 7 can rotate in a relatively short time after the start of energization. And adsorbed to the pole head 4 side. On the other hand, the plunger 2 cannot operate in a time as short as the amateur 7 due to the influence of the viscosity of the fluid existing inside the cylinder 1. Therefore, when the armature 7 rotates and is attracted to the pole head 4 side, the plunger 2 is still in the state of being stopped at the bottom side of the cylinder 1 as shown in FIG.
<Action>
Hereinafter, the operation of the attraction magnet 8 and the temperature-sensitive magnetic body 9 of Embodiment 1 will be described.

  Before the overcurrent flows, the current flowing through the electromagnetic coil 5, the main electric path 11, and the temperature-sensitive magnetic body 9 is small, and the temperature-sensitive magnetic body 9 is below the Curie temperature. Accordingly, at this time, the temperature-sensitive magnetic body 9 has properties as a magnetic body. Accordingly, the magnetic flux of the attracting magnet 8 passes through the temperature-sensitive magnetic body 9 as shown by the broken line in FIG. Accordingly, an attractive force acting on the plunger 2 toward the attractive magnet 8 side is applied.

When an overcurrent flows, the temperature of the temperature-sensitive magnetic body 9 rises due to conduction heat and radiant heat from the electromagnetic coil 5 and the main electric path 11, and Joule heat generation of the temperature-sensitive magnetic body 9, and the temperature-sensitive magnetic body 9 becomes curie. Over temperature. At this time, the temperature-sensitive magnetic body 9 has a property as a non-magnetic body. Therefore, the magnetic flux of the attraction magnet 8 returns from the temperature-sensitive magnetic body 9 to the attraction magnet 8 as shown by the broken line in FIG. Accordingly, the attracting force toward the attracting magnet 8 side hardly acts on the plunger 2.
<Effect>
Hereinafter, effects of the electromagnetic tripping device of the first embodiment will be described. The electromagnetic trip device as a comparative example does not have the attracting magnet 8, the temperature-sensitive magnetic body 9, and the auxiliary yoke 10.

In the low overcurrent region, the temperature is about 10 seconds after energization start (when energization is about twice the rated current) to 30 seconds (when energization is about 1.25 times the rated current). The magnetic body 9 becomes higher than the Curie temperature. Therefore, at this time, the temperature-sensitive magnetic body 9 has a property as a non-magnetic body, and the attracting force toward the attracting magnet 8 hardly acts on the plunger 2.

  Therefore, after the time when the temperature-sensitive magnetic body 9 becomes equal to or higher than the Curie temperature, the same time delay characteristic as that of the electromagnetic trip device of the comparative example having no attracting magnet 8, the temperature-sensitive magnetic body 9, and the auxiliary yoke 10 is obtained.

  On the other hand, the breaker equipped with the electromagnetic tripping device of the comparative example is about 1 minute from the start of energization (in the case of energization of about twice the rated current) to about 6 minutes (about 1.25 times the rated current) Trip).

  Therefore, in the case of the breaker equipped with the electromagnetic tripping device of the first embodiment, considering the time until the temperature-sensitive magnetic body 9 has a property as a non-magnetic body, about 1 minute and 10 seconds from the start of energization. (In the case of energization of about twice the rated current) to about 6 minutes 30 seconds (in the case of energization of about 1.25 times the rated current), the trip operation is performed.

  That is, in the case of the breaker equipped with the electromagnetic trip device of the first embodiment, the operation time in the low overcurrent region is about 10% slower than the case of the electromagnetic trip device of the comparative example, but almost the same operation. You will get time.

  In the starting current region, the temperature-sensitive magnetic body 9 is about 3 seconds (when energizing is about 8 times the rated current) to about 5 seconds (when energizing is about 6 times the rated current). Exceeds the Curie temperature. Therefore, at this time, the temperature-sensitive magnetic body 9 has a property as a non-magnetic body, and the attracting force toward the attracting magnet 8 hardly acts on the plunger 2. Therefore, after the time when the temperature-sensitive magnetic body 9 becomes equal to or higher than the Curie temperature, the time delay characteristic is the same as that of the electromagnetic trip device of the comparative example that does not include the attracting magnet 8 and the temperature-sensitive magnetic body 9.

  On the other hand, the breaker equipped with the electromagnetic tripping device of the comparative example is about 3 seconds from the start of energization (about 8 times the rated current) to about 7 seconds (about 6 times the rated current) In the case of).

  Therefore, the breaker equipped with the electromagnetic trip device of the first embodiment is about 6 seconds from the start of energization (in the case of energization about 8 times the rated current) to about 12 seconds (about 6 times the rated current). (In the case of energization), it will trip.

  Therefore, compared with the case of the electromagnetic tripping device of the comparative example, in the case of the breaker equipped with the electromagnetic tripping device of the first embodiment, the operation time in the starting current region is about 200% and is delayed.

Since the current is very large in the short-circuit current region, the magnetic flux generated by the electromagnetic coil 5 is very large. Therefore, the magnetic attractive force acting on the armature 7 does not depend on the distance between the yoke 6 and the plunger 2. Therefore, when the electromagnetic trip device of Embodiment 1 is mounted on a circuit breaker, the operating time of the circuit breaker is equivalent to that of the comparative example in the short circuit current region.
(Embodiment 2)
Hereinafter, an electromagnetic tripping device according to Embodiment 2 will be described with reference to FIG.
<Configuration>
Hereinafter, the configuration of the electromagnetic tripping device according to the second embodiment will be described. Note that the description of the same components as those of the first embodiment is omitted.

The attraction magnet 8 is made of a permanent magnet and is provided on the bottom side of the cylinder 1. The attraction magnet 8 is magnetized so that the direction of the magnetic flux is perpendicular to the axial direction of the plunger 2. That is, it is magnetized in the direction indicated by the arrow in FIG.

  As shown in FIG. 3, the temperature-sensitive magnetic body 9 is directly connected to the main electric path 11, and a current flowing through the main electric path 11 flows through the temperature-sensitive magnetic body 9. In the present invention, the temperature-sensitive magnetic body 9 may be connected to the main electric circuit 11 via an insulating member such as a nonmetal. In the present invention, the temperature-sensitive magnetic body 9 is not necessarily connected to the main electric circuit 11. That is, there may be a gap between the temperature-sensitive magnetic body 9 and the main electric path 11 or the electromagnetic coil 5 so that the temperature-sensitive magnetic body 9 is heated by the heat generated when the main electric path 11 or the electromagnetic coil 5 is energized. Alternatively, the temperature-sensitive magnetic body 9 may be arranged in the vicinity of the main electric path 11 or the electromagnetic coil 5.

The supplementary yoke 13 is made of a magnetic material and provided at a position facing the temperature-sensitive magnetic material 9. The bottom of the cylinder 1 and the attracting magnet 8 are disposed so as to be sandwiched between the supplementary yoke 13 and the temperature-sensitive magnetic body 9, and the attracting magnet 8, the supplementary yoke 13, the large-diameter portion 2 a of the plunger 2 and the temperature-sensitive part. The magnetic body 9 forms a closed magnetic path.
<Operation>
Since it is the same as that of the first embodiment, it is omitted.
<Action>
Hereinafter, the operation of the attraction magnet 8 and the temperature-sensitive magnetic body 9 of Embodiment 1 will be described.

  Before the overcurrent flows, the current flowing through the electromagnetic coil 5, the main electric path 11, and the temperature-sensitive magnetic body 9 is small, and the temperature-sensitive magnetic body 9 is below the Curie temperature. Accordingly, at this time, the temperature-sensitive magnetic body 9 has properties as a magnetic body. Accordingly, the magnetic flux of the attraction magnet 8 passes through the supplementary yoke 13, the bottom side of the cylinder 1 of the plunger 2, and the temperature-sensitive magnetic body 9, and returns to the attraction magnet 8, as shown by the broken line in FIG. Accordingly, an attractive force acting on the plunger 2 toward the attractive magnet 8 side is applied.

When an overcurrent flows, the temperature of the temperature-sensitive magnetic body 9 rises due to conduction heat and radiant heat from the electromagnetic coil 5 and the main electric path 11, and Joule heat generation of the temperature-sensitive magnetic body 9, and the temperature-sensitive magnetic body 9 becomes curie. Over temperature. At this time, the temperature-sensitive magnetic body 9 has a property as a non-magnetic body. If the temperature-sensitive magnetic body 9 is a non-magnetic body, it is difficult for magnetic flux to flow through the temperature-sensitive magnetic body 9 portion. Therefore, the magnetic flux of the attraction magnet 8 returns from the supplementary yoke 13 to the attraction magnet 8 as shown by the broken line in FIG. Therefore, the attracting force toward the attracting magnet 8 hardly acts on the plunger 2.
<Effect>
Since it is the same as that of the first embodiment, the details are omitted.

  Compared to the case of the electromagnetic trip device of the comparative example, in the case of the breaker equipped with the electromagnetic trip device of Embodiment 1, the operation time in the low overcurrent region is delayed by about 10%, but almost the same operation time. Is obtained.

  In the starting current region, compared with the electromagnetic tripping device of the comparative example, in the case of the breaker equipped with the electromagnetic tripping device of the first embodiment, the operation time is about 200% and is delayed.

In the short-circuit current region, the magnetic attractive force acting on the armature 7 does not depend on the distance between the yoke 6 and the plunger 2. Therefore, even when the electromagnetic trip device of Embodiment 2 is mounted on the circuit breaker, the circuit breaker The operation time is equal to that of the comparative example.
(Embodiment 3)
Hereinafter, an electromagnetic tripping device according to Embodiment 3 will be described with reference to FIG.

  Hereinafter, the configuration of the electromagnetic tripping device according to the third embodiment will be described. Note that the description of the same components as those of the second embodiment is omitted.

  In the third embodiment, a temperature-sensitive magnetic body 9 is arranged instead of the supplementary yoke 13 of the second embodiment. That is, it has the structure which has a pair of thermosensitive magnetic body 9 which opposes.

  As shown in FIG. 4, the temperature-sensitive magnetic body 9 is directly connected to the main electric path 11, and a current flowing through the main electric path 11 flows into the temperature-sensitive magnetic body 9. In the present invention, the temperature-sensitive magnetic body 9 may be connected to the main electric circuit 11 via an insulating member such as a nonmetal. In the present invention, the temperature-sensitive magnetic body 9 is not necessarily connected to the main electric circuit 11. That is, there may be a gap between the temperature-sensitive magnetic body 9 and the main electric path 11 or the electromagnetic coil 5 so that the temperature-sensitive magnetic body 9 is heated by the heat generated when the main electric path 11 or the electromagnetic coil 5 is energized. Alternatively, the temperature-sensitive magnetic body 9 may be arranged in the vicinity of the main electric path 11 or the electromagnetic coil 5.

  The bottom part of the cylinder 1 and the attracting magnet 8 are arranged so as to be sandwiched between a pair of temperature-sensitive magnetic bodies 9, and the magnetism is closed by the attracting magnet 8, the large-diameter part 2 a of the plunger 2 and the temperature-sensitive magnetic body 9. A path is formed.

Since the operation, action, and effect are the same as in the second embodiment, they are omitted.
(Embodiment 4)
Hereinafter, an electromagnetic tripping device according to Embodiment 4 will be described with reference to FIG.

  In the fourth embodiment, in addition to the configuration of the first embodiment, an elastic body 12 is provided between the plunger 2 and the bottom of the cylinder 1. By providing the elastic body 12, in addition to the effects described in the first to third embodiments, it is possible to suppress the generation of a beat sound that occurs when the plunger 2 collides with the bottom of the cylinder 1.

  In order to increase the force with which the attracting magnet 8 attracts the plunger 2, the elastic body 12 is preferably a soft magnetic material.

Further, the electromagnetic tripping device of the present invention may be provided with the elastic body 12 in the configuration of the second and third embodiments.
(Embodiment 5)
The block diagram of the circuit breaker carrying the electromagnetic trip apparatus 100 which concerns on FIG. 6 at Embodiment 1 is shown. By operating the handle 52, the contact 53 is closed and closed. When the overcurrent flows, the armature 7 moves to the plunger 2 side, and the armature 7 pushes the latch 50. When the latch 50 is pushed, the mechanism 51 operates and the contact 53 opens.

In addition, the circuit breaker of this invention may be a circuit breaker which mounts the electromagnetic trip apparatus of Examples 2-4.
(Conclusion)
As described above, the embodiments have been described as examples of the technology in the present invention. For this purpose, the accompanying drawings and detailed description are provided.

  Accordingly, among the components described in the accompanying drawings and the detailed description, not only the components essential for solving the problem, but also the components not essential for solving the problem in order to illustrate the above technique. May also be included. Therefore, it should not be immediately recognized that these non-essential components are essential as those non-essential components are described in the accompanying drawings and detailed description.

  Moreover, since the above-mentioned embodiment is for demonstrating the technique in this invention, a various change, replacement, addition, abbreviation, etc. can be performed in a claim or its equivalent range.

DESCRIPTION OF SYMBOLS 1 Cylinder 2 Plunger 2a Large diameter part 2b Protrusion part 3 Brake spring 4 Pole head 5 Electromagnetic coil 6 Yoke 6a Parallel piece 6b Right angle piece 7 Amateur 8 Attraction magnet 9 Temperature-sensitive magnetic body 10 Auxiliary yoke 11 Main electric circuit 12 Elastic body 13 Supplementary yoke 50 Latch 51 Mechanism 52 Handle 53 Contact 100 Electromagnetic trip device

Claims (9)

A cylinder made of a non-magnetic material having a cylindrical shape with a bottom;
A plunger made of a magnetic material and provided inside the cylinder;
A braking spring that pushes the plunger toward the rear end that is the bottom of the cylinder;
A pole head made of a magnetic material and sealing the opening on the front end side of the cylinder;
An electromagnetic coil provided so as to wind the cylinder and a magnetic body; a parallel piece provided outside the electromagnetic coil and disposed parallel to the axial direction of the cylinder; and a right-angle piece extending toward the cylinder A yoke having
An armature made of a magnetic material and connected to the yoke in such a way that it can rotate toward the pole head,
An attraction magnet made of a permanent magnet, provided on the bottom side of the plunger, and giving a magnetic attraction force in a direction toward the cylinder bottom to the plunger;
A temperature-sensitive magnetic body provided in the vicinity of the plunger and the attraction magnet, and having a magnetic property largely changed near the Curie temperature;
An electromagnetic trip device in which the magnetic attractive force is reduced when the temperature-sensitive magnetic body becomes non-magnetic due to a temperature rise. The temperature-sensitive magnetic body is
The electromagnetic trip device according to claim 1, wherein the electromagnetic trip device is provided in the vicinity of at least one of the electromagnetic coil and a main electric circuit that supplies current to the electromagnetic coil. The temperature-sensitive magnetic body is
The electromagnetic trip device according to claim 2, wherein the electromagnetic trip device is electrically connected to the electromagnetic coil or the main electric circuit. The electromagnetic trip device according to any one of claims 1 to 3, wherein the temperature-sensitive magnetic body is provided between a bottom surface of the cylinder and the attraction magnet. Having a supplementary yoke made of magnetic material,
The electromagnetic trip device according to claim 1, wherein a closed magnetic path is formed by the attraction magnet, the supplementary yoke, the plunger, and the temperature-sensitive magnetic body. A plurality of the temperature-sensitive magnetic bodies;
A closed magnetic path is formed by the attraction magnet, the plunger, and the temperature-sensitive magnetic body,
The electromagnetic trip device according to any one of claims 1 to 3, wherein at least one of the temperature-sensitive magnetic bodies is arranged to increase in temperature when the main electric circuit is energized. The electromagnetic trip device according to any one of claims 1 to 6, wherein an elastic body is provided between a bottom of the cylinder and the plunger. The electromagnetic trip device according to claim 7, wherein the elastic body is a soft magnetic material. The circuit breaker provided with the electromagnetic trip device of any one of Claims 1-8.