Electromagnetic operation type opening / closing device

Abstract

To provide an electromagnetic operation type switchgear that can prevent a reduction in the mechanical strength of an iron core, and can prevent an increase in the size of the iron core.SOLUTION: An electromagnetic operation type switchgear comprises: fixing plates 5-7 fixing a coil 4 and a stationary iron core 1; a plunger 2 penetrating the coil; a drive rod 11 connected with the plunger and moving in an axial direction with the plunger; and a permanent magnet 3 arranged on an upper part of the coil, and the electromagnetic operation type switchgear excites the coil to suck in the plunger and causes a magnetic flux generated by a permanent magnet to flow on an opposite surface of the plunger and the stationary iron core to maintain the suction state of the plunger. Slits 1a, 2a are provided in a contact part of at least one of the plunger and the stationary iron core arranged facing each other at a predetermined interval in a circumferential direction, from an outer peripheral side to a side of the drive rod. The slits are formed to be shallow on the side of the drive rog and deep on the outer peripheral side.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an electromagnetic operation type opening and closing device, and more particularly to an electromagnetic operation type opening and closing device suitable for opening and closing contacts of a switch using the electromagnetic force of an electromagnetic operation device.

Background Art

[0002] As a prior art document in this technical field, an opening and closing device described in Patent Document 1 can be cited.

[0003] This Patent Document 1 provides an opening and closing device that supplies a pulse current to two coils and performs an opening and closing operation by electromagnetic drive. In order to perform electromagnetic drive with high efficiency and high speed and to reduce the capacity of the power supply for the opening and closing poles, a switch section composed of a fixed electrode and a movable electrode that can be separated and contacted, a movable section fixed via a magnetic body between a movable shaft continuous with the movable electrode and a movable coil, and a fixed section with a magnetic body arranged on the inner diameter side of a fixed coil arranged to face this movable section are provided, thereby enabling an increase in the generated magnetic field between the coils and a high-speed rise.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the electromagnetic drive device described in the above-mentioned Patent Document 1, a plurality of slits provided to suppress eddy currents generated inside the iron core when the coil is energized have a configuration that penetrates axially from the contact portion between the movable iron core and the fixed iron core to the opposite side of the contact portion of each iron core, or a configuration in which the slit on the inner diameter side and the slit on the outer diameter side are connected.

[0006] In this electromagnetic drive device, when the coil is energized, the movable iron core moves at high speed and collides with the fixed iron core. However, since a plurality of slits are provided, the mechanical strength of the iron core decreases, and the slits provided in each iron core may be deformed by the impact force caused by the collision, and ultimately the slits may be crushed. When the slits are crushed and the slit grooves disappear, the eddy current inside the iron core cannot be suppressed, and the operating speed decreases.

[0007] As countermeasures, it is conceivable to reduce the number of slits to ensure the mechanical strength of the iron core, or to increase the groove width so that the grooves do not come into contact even if the slits are crushed, or to increase the size of the iron core to ensure the mechanical strength. However, in any case, the device becomes larger in size and the operating speed decreases, so it is a trade-off relationship.

[0008] The present invention has been made in view of the above points, and an object thereof is to provide an electromagnetic operation type opening and closing device that can suppress a decrease in the mechanical strength of an iron core and can suppress an increase in the size of the iron core.

Means for Solving the Problems

[0009] In order to achieve the above object, the electromagnetic operation type opening and closing device of the present invention includes a fixed flat plate to which a coil and a fixed iron core are fixed, a plunger that penetrates the coil, a drive rod that is connected to the plunger and moves axially together with the plunger, and a permanent magnet disposed above the coil. The coil is excited to attract the plunger, and a magnetic flux generated by the permanent magnet is passed through the opposing surfaces of the plunger and the fixed iron core to maintain the attracted state of the plunger. At the same time, a current in the opposite direction to the time when the plunger is attracted is passed through the coil to release the attracted state of the plunger. In the electromagnetic operation type opening and closing device, at least one contact portion side of the plunger and the fixed iron core, which are arranged opposite to each other with a predetermined interval in the circumferential direction, is provided with a slit extending from the outer peripheral side to the drive rod side, and the slit is formed such that the drive rod side is shallow and the outer peripheral side is deep.

Effects of the Invention

[0010] According to the present invention, an electromagnetic operation type switching device capable of suppressing a decrease in the mechanical strength of an iron core and suppressing an increase in the size of the iron core can be obtained.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0012] Hereinafter, the electromagnetic operation type switching device of the present invention will be described based on the illustrated embodiments. In each embodiment, the same reference numerals are used for the same components.

Example

[0013] FIGS. 1, 2, 3, and 4 show Embodiment 1 of the electromagnetic operation type switching device of the present invention.

[0014] FIG. 1 is a cross-sectional view of the operating mechanism portion of the electromagnetic operating switchgear of Example 1 as viewed from the side, showing a state where the fixed core 1 and the plunger 2 are not in contact. FIG. 2 is also a cross-sectional view of the operating mechanism portion of the electromagnetic operating switchgear of Example 1 as viewed from the side, showing a state where the fixed core 1 and the plunger 2 are in contact. FIG. 3 shows a side view of the plunger 2, and FIG. 4 shows a bottom view of the plunger 2.

[0015] As shown in FIGS. 1 and 2, the operating mechanism portion of the electromagnetic operating switchgear of this embodiment is roughly composed of a fixed core 1, a plunger 2, a permanent magnet 3, a coil 4, a first fixed flat plate 5, a second fixed flat plate 6, a third fixed flat plate 7, a movable flat plate 8, a first cylindrical core 9, a second cylindrical core 10, and a drive rod 11 arranged on their axes.

[0016] The first cylindrical core 9 is clamped between the first fixed flat plate 5 and the second fixed flat plate 6, the second cylindrical core 10 is clamped between the second fixed flat plate 6 and the third fixed flat plate 7, and the plunger 2 and the movable flat plate 8 are connected to the drive rod 11.

[0017] The material of the drive rod 11 is a non-magnetic material such as stainless steel, the permanent magnet 3 is a magnet with a very high magnetic force such as a neodymium-based magnet, and the others are roughly composed of a magnetic material such as a steel material.

[0018] When an input command is input from a control board or the like outside the operating mechanism portion (not shown), the coil 4 of the electromagnet is energized, and a magnetic field is formed around the coil 4 in the path of the plunger 2 → the fixed core 1 → the third fixed flat plate 7 → the second cylindrical core 10 → the second fixed flat plate 6 → the plunger 2. Due to the magnetic field, a downward suction force acts on the plunger 2, and the plunger 2 moves toward the fixed core 1 together with the drive rod 11, and the plunger 2 is adsorbed to the fixed core 1.

[0019] At this time, since the direction of the magnetic field formed by the permanent magnet 3 also becomes the same as the direction of the magnetic field generated with the excitation of the coil 4, the plunger 2 moves toward the fixed iron core 1 in a state where the attractive force is increased. The state where the plunger 2 and the fixed iron core 1 are in contact (the state in FIG. 2) becomes the energized state of the switch.

[0020] Next, when an opening command is input from an external control board (not shown) and a signal associated with the opening command is input from the control board to the coil 4, a current in the opposite direction to that at the time of energization flows through the coil 4, and a magnetic field in the opposite direction to that during the energization operation is formed around the coil 4.

[0021] In this case, the magnetic flux generated from the coil 4 and the magnetic flux generated from the permanent magnet 3 cancel each other out, the attractive force in the axial direction of the plunger 2 becomes upward, the plunger 2 separates from the fixed iron core 1 and moves upward together with the drive rod 11. When the drive rod 11 moves upward with the movement of the plunger 2, the opening operation of the switch is interlocked and performed, and it stops at a predetermined position to enter the open state.

[0022] Here, the current flowing through the coil 4 due to the energization command or opening command from the control board is a transient current whose magnitude changes with time, and the magnetic flux inside the magnetic components such as the plunger 2 and the fixed iron core 1 where the magnetic path is formed also changes with time.

[0023] Due to the magnetic flux that changes with this time, eddy currents are generated inside the magnetic material, and the magnetic flux magnetic field due to the eddy currents is generated in a direction that obstructs the magnetic path. The magnetic field generated by the eddy currents obstructs the magnetic field due to the coil energization and becomes a factor that slows down the operation.

[0024] Therefore, in the first embodiment, on each contact portion side of the plunger 2 and the fixed core 1 that have a predetermined interval in the circumferential direction and are arranged opposite to each other, a slit 2a on the plunger 2 side and a slit 1a on the fixed core 1 side are provided from the outer peripheral side to the drive rod 11 side (the hatched portions shown in FIGS. 1 and 2 are the slits 2a and 1a). Moreover, the slit 2a on the plunger 2 side and the slit 1a on the fixed core 1 side are formed such that the drive rod 11 side is shallow (the hatched portion is short in the axial direction) and the outer peripheral side is deep (the hatched portion is long in the axial direction).

[0025] Even if the fixed core 1 and the plunger 2 collide during the closing operation of the switch in the fixed core 1 and the plunger 2 provided with such slits 1a and 2a, since the drive rod 11 side of the slits 1a and 2a is shallowly formed, a decrease in the mechanical strength on the drive rod 11 side can be suppressed compared to the outer peripheral side. Therefore, the amount of deformation of the slits 1a and 2a can be suppressed, and an increase in the size of the core can be suppressed.

Embodiment

[0026] FIG. 5 shows a second embodiment of the electromagnetic operation type switch of the present invention.

[0027] FIG. 5 is a cross-sectional view of the operation mechanism portion in the electromagnetic operation type switch of the second embodiment as viewed from the side, showing a state where the fixed core 1 and the plunger 2 are not in contact. Description of the same parts as in the first embodiment will be omitted.

[0028] In the electromagnetic operation type switch in the present embodiment shown in FIG. 5, a slit 2a is provided only on the contact portion side of the plunger 2 from the outer peripheral side to the drive rod 11 side (the hatched portion shown in FIG. 5 is the slit 2a). Moreover, the slit 2a on the plunger 2 side is formed such that the drive rod 11 side is shallow (the hatched portion is short in the axial direction) and the outer peripheral side is deep (the hatched portion is long in the axial direction).

[0029] Even when the plunger 2 provided with such a slit 2a collides with the fixed core 1 during the closing operation of the switch, since the drive rod 11 side of the slit 2a is formed shallowly, the decrease in the mechanical strength of the drive rod 11 side can be suppressed compared to the outer peripheral side. Therefore, the amount of deformation of the slit 2a can be suppressed, and the enlargement of the core can be suppressed.

Embodiment

[0030] FIG. 6 shows Embodiment 3 of the electromagnetic operation type switchgear of the present invention.

[0031] FIG. 6 is a cross-sectional view of the operation mechanism portion of the electromagnetic operation type switchgear of Embodiment 3 as viewed from the side, showing a state where the fixed core 1 and the plunger 2 are not in contact. Description of the same parts as in Embodiment 1 will be omitted.

[0032] In the electromagnetic operation type switchgear according to the present embodiment shown in FIG. 6, a slit 1a is provided only on the contact portion side of the fixed core 1, extending from the outer peripheral side to the drive rod 11 side (the hatched portion shown in FIG. 6 is the slit 1a). Moreover, the slit 1a on the fixed core 1 side is formed such that the drive rod 11 side is shallow (the hatched portion is short in the axial direction) and the outer peripheral side is deep (the hatched portion is long in the axial direction).

[0033] Even when the fixed core 1 provided with such a slit 1a collides with the plunger 2 during the closing operation of the switch, since the drive rod 11 side of the slit 1a is formed shallowly, the decrease in the mechanical strength of the drive rod 11 side can be suppressed compared to the outer peripheral side. Therefore, the amount of deformation of the slit 1a can be suppressed, and the enlargement of the core can be suppressed.

[0034] Note that the present invention is not limited to the above-described embodiments and includes various modifications. For example, the above-described embodiments have been specifically described in order to explain the present invention clearly, and are not necessarily limited to those having all the configurations described. Also, a part of the configuration of one embodiment can be replaced with a part of the configuration of another embodiment. Further, the configuration of another embodiment can be added to the configuration of one embodiment. Also, for a part of the configuration of each embodiment, it can be deleted, a part of another configuration can be added, and it can be replaced with a part of another configuration.

Description of Reference Numerals

[0035] 1... fixed core, 1a... slit of the fixed core, 2... plunger, 2a... slit of the plunger, 3... permanent magnet, 4... coil, 5... first fixed flat plate, 6... second fixed flat plate, 7... third fixed flat plate, 8... movable flat plate, 9... first cylindrical core, 10... second cylindrical core, 11... drive rod, 12... slit.

Claims

1. An electromagnetic-operated switching device comprising a fixed flat plate to which a coil and a fixed iron core are fixed, a plunger passing through the coil, a drive rod connected to the plunger and moving axially together with the plunger, and a permanent magnet disposed above the coil, which excites the coil to attract the plunger, allows the magnetic flux generated by the permanent magnet to flow through the opposing surfaces of the plunger and the fixed iron core to maintain the attracted state of the plunger, and releases the attracted state of the plunger by flowing a current in the opposite direction to the current when the plunger is attracted through the coil, wherein at least one contact portion side of the plunger and the fixed iron core, which are arranged opposite to each other with a predetermined interval in the circumferential direction, is provided with a slit extending from the outer peripheral side to the drive rod side, and the slit is formed such that the drive rod side is shallower and the outer peripheral side is deeper.

2. The electromagnetic-operated switching device according to Claim 1, wherein the slit is provided on the contact portion sides of both the plunger and the fixed iron core.

3. The electromagnetic-operated switching device according to Claim 1, wherein the slit is provided only on the contact portion side of the plunger.

4. The electromagnetic-operated switching device according to Claim 1, wherein the slit is provided only on the contact portion side of the fixed iron core.

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