JP7492898B2 - Electromagnetic actuator and vacuum circuit breaker having electromagnetic actuator - Google Patents

Description

The present invention relates to an electromagnetic actuator and a vacuum circuit breaker having an electromagnetic actuator.

JP 2006-059557 A (Patent Document 1) is a background technology in this technical field.

Patent document 1 describes a vacuum circuit breaker that has a vacuum opening and closing unit in which an operating rod that drives the opening and closing contacts in the vertical direction is installed in a vacuum container, and an electromagnetic driving unit in which a driving mechanism that drives a driving rod connected to the operating rod is installed.

JP 2006-059557 A

Patent document 1 describes a vacuum circuit breaker having an electromagnetic drive unit (electromagnetic actuator) in which a drive mechanism that drives a drive rod is installed.

When the electromagnetic actuator is operating, that is, when the electromagnet is operating, a rotational force is generated around the drive rod in the movable iron core that constitutes the electromagnet.

In particular, if the horizontal cross section of the components that make up the electromagnet (movable iron core, fixed iron core, coil) is rectangular rather than circular, when the electromagnet is in operation (when the movable iron core moves), a rotational force is generated in the movable iron core, and the movable iron core may come into contact with the fixed iron core or coil that is installed around the outer periphery of the movable iron core.

In this case, contact between the movable core and the fixed core or coil can cause sliding wear, resulting in the generation of metal dust, which can ultimately lead to deformation of the movable core, fixed core, or coil.

However, Patent Document 1 does not describe an electromagnetic actuator that suppresses sliding wear between the movable iron core and the fixed iron core or coil when the electromagnet is in operation, reduces the generation of metal dust, and suppresses deformation between the movable iron core and the fixed iron core or coil.

Therefore, the present invention provides an electromagnetic actuator and a vacuum circuit breaker having an electromagnetic actuator that suppresses sliding wear between the movable iron core and the fixed iron core or coil when the electromagnet is in operation, reduces the generation of metal dust, and suppresses deformation between the movable iron core and the fixed iron core or coil.

In order to solve the above-mentioned problems, the electromagnetic actuator of the present invention has an electromagnet having a rectangular cross section in horizontal cross section and a drive rod installed on the central axis of the electromagnet, the electromagnet having a coil , a movable core installed on the drive rod and sliding on the inner circumference of the coil , a first fixed core installed at the bottom of the coil, a second fixed core installed on the outer circumference of the coil, and a third fixed core installed at the top of the coil, wherein a rotation prevention member for suppressing rotation of the movable core is installed on the first fixed core, and a guide groove hole into which the rotation prevention member is inserted is formed in the movable core , the length of the guide groove hole is longer than the length of the rotation prevention member, and the diameter of the rotation prevention member is the same as the diameter of the drive rod .

The vacuum circuit breaker of the present invention is also characterized by having the electromagnetic actuator described above.

The present invention provides an electromagnetic actuator and a vacuum circuit breaker having an electromagnetic actuator that suppresses sliding wear between the movable core and the fixed core or coil when the electromagnet is in operation, reduces the generation of metal dust, and suppresses deformation between the movable core and the fixed core or coil.

Note that issues, configurations and effects other than those mentioned above will become clearer in the explanation of the examples below.

FIG. 2 is an explanatory diagram illustrating a vacuum circuit breaker 100 according to a first embodiment. 2 is an explanatory diagram for explaining an operation mechanism unit 2 described in the first embodiment. FIG. FIG. 2 is a schematic top view illustrating the vacuum circuit breaker 100 according to the first embodiment. 11 is an explanatory diagram for explaining an operation mechanism unit 2 described in a second embodiment. FIG. FIG. 11 is a schematic top view illustrating a vacuum circuit breaker 100 according to a second embodiment.

The following describes an embodiment of the present invention with reference to the drawings. Note that the same reference numerals are used to designate substantially identical or similar configurations, and where explanations are redundant, they may be omitted.

First, we will explain the vacuum circuit breaker 100 described in Example 1.

Figure 1 is an explanatory diagram illustrating the vacuum circuit breaker 100 described in the first embodiment.

The vacuum circuit breaker 100 is an electromagnetically operated switching device, and has a main circuit switching section 1 shown on the left side of FIG. 1, an electromagnetic operator (hereinafter referred to as the operating mechanism section 2) shown on the right side of FIG. 1, and a link mechanism section 3 shown on the lower side of FIG. 1.

The main circuit opening/closing unit 1 has a fixed side conductor 8, a vacuum valve 9 having a pair of contacts (fixed contact and movable contact) that can be opened and closed as an interrupter, a movable side conductor 10, a flexible conductor 11 that electrically connects the vacuum valve 9 (movable side) and the movable side conductor 10, a contact pressure spring 13 that applies a contact load to the contact (movable contact) of the vacuum valve 9, an insulating rod 12 that electrically insulates the vacuum valve 9 and the contact pressure spring 13, and a connecting plate 14 that pushes up the contact pressure spring 13, and has an insulating frame 4 that electrically insulates them from the operation mechanism unit 2 and the link mechanism unit 3.

The operating mechanism 2 has a permanent magnet 15, a coil 16, a movable core 50 made of a magnetic material such as iron, a first fixed core 51 made of a magnetic material such as iron, a second fixed core 52 made of a magnetic material such as iron, a third fixed core 53 made of a magnetic material such as iron, a breaker spring 18 that opens the contacts (movable contacts) of the vacuum valve 9, and a drive rod 19 installed on the central axis of these (electromagnets described below).

The coil 16, the movable core 50, the first fixed core 51, the second fixed core 52, and the third fixed core 53 form an electromagnet. The second fixed core 52 is installed on the outer periphery of the coil 16, the first fixed core 51 is installed on the lower part of the coil 16, and the third fixed core 53 is installed on the upper part of the coil 16. The movable core 50 is installed (connected) to the drive rod 19 and slides on the inner periphery of the coil 16.

The link mechanism 3 has a shaft 20 journaled in the link mechanism case 6, a first lever 22 fixed to the shaft 20 and connected to the connecting plate 14 by a first pin 21, and a second lever 24 fixed to the shaft 20 and connected to the drive rod 19 by a second pin 23, and has the link mechanism case 6 that covers these. The insulating frame 4 is fixed to the link mechanism case 6.

The vacuum circuit breaker 100 may be either a one-phase circuit breaker or a three-phase circuit breaker. In the case of a three-phase circuit breaker, three main circuit switching units 1 are arranged in a line in the depth direction of FIG. 1 (perpendicular to the paper surface).

Then, the vertical linear motion of the drive rod 19 is transmitted to the connecting plate 14 via the second lever 24 and the first lever 22, and the contacts (movable contacts) of the vacuum valve 9 are opened and closed. In other words, the upward linear motion of the drive rod 19 is transmitted to the connecting plate 14 via the second lever 24 and the first lever 22, and the contacts (movable contacts) of the vacuum valve 9 are opened (cut off), and the downward linear motion of the drive rod 19 is transmitted to the connecting plate 14 via the second lever 24 and the first lever 22, and the contacts (movable contacts) of the vacuum valve 9 are closed (closed).

Note that Figure 1 shows the vacuum valve 9 in a closed state.

<From open to closed state>
When a closing command to change the vacuum valve 9 from an open state to a closed state is input to the operating mechanism unit 2 from a control board (not shown) or the like, a current flows through the coil 16, and when the coil 16 is excited, a magnetic field is formed around the coil 16 through the path of the movable iron core 50 ⇒ first fixed iron core 51 ⇒ second fixed iron core 52 ⇒ third fixed iron core 53 ⇒ movable iron core 50.

This magnetic field generates a downward attractive force on the movable core 50. Furthermore, the direction of the magnetic field formed by the permanent magnet 15 is the same as the direction of the magnetic field generated by the excitation of the coil 16. As a result, the downward attractive force generated on the movable core 50 increases.

As a result, the movable core 50 moves toward the first fixed core 51, the bottom surface of the movable core 50 is attracted to the first fixed core 51, and the closing operation is performed by the electromagnet. It is preferable that a small gap is formed between the bottom surface of the movable core 50 and the first fixed core 51.

When the electromagnet performs the closing operation in this manner, the driving rod 19 installed on the movable core 50 moves linearly downward against the elastic force of the cutoff spring 18, and the driving force associated with the electromagnetic force generated by the electromagnet is transmitted to the link mechanism 3. This driving force is transmitted to the connecting plate 14 via the second lever 24 and the first lever 22, causing the insulating rod 12 to move upward, bringing the fixed contact and movable contact of the vacuum valve 9 into contact, performing the closing operation of the vacuum valve 9, and the vacuum valve 9 entering the closed state (the state shown in Figure 1).

When the vacuum valve 9 is closed, the pressure spring 13 is not compressed until the fixed contact and the movable contact of the vacuum valve 9 come into contact, but when the fixed contact and the movable contact of the vacuum valve 9 come into contact, the pressure spring 13 is compressed and continues to be compressed until the closing operation of the vacuum valve 9 is completed. On the other hand, the cutoff spring 18 always remains compressed when the vacuum valve 9 is in the closed state.

<From closed state to open state>
Next, when an opening command for changing the vacuum valve 9 from a closed state to an open state is input to the operation mechanism 2 from a control board (not shown) or the like, a signal accompanying the opening command is output from the control board to the coil 16. This signal causes a current to flow through the coil 16 in the opposite direction to that during the closing operation, and a magnetic field is formed around the coil 16 in the opposite direction to that during the closing operation.

The magnetic flux generated by the coil 16 and the magnetic flux generated by the permanent magnet 15 cancel each other out, and the attractive force at the bottom surface of the movable core 50 becomes weaker than the elastic force generated by the cutoff spring 18 and the contact pressure spring 13. As a result, the bottom surface of the movable core 50 moves away from the first fixed core 51, and the drive rod 19 installed on the movable core 50 moves linearly upward, and the electromagnet performs a pole-opening operation.

When the opening operation is performed by the electromagnet in this manner, the driving rod 19 installed on the movable core 50 moves linearly upward, and in conjunction with the linear movement of this driving rod 19, the connecting plate 14 and the insulating rod 12 move downward via the second lever 24 and the first lever 22, the fixed contact and the movable contact of the vacuum valve 9 are separated, the contact between the fixed contact and the movable contact of the vacuum valve 9 is released, the opening operation of the vacuum valve 9 is performed, and the vacuum valve 9 is in an open state.

When the vacuum valve 9 is opened, the compressed pressure spring 13 first expands, and when the pressure spring 13's retainer 25 comes into contact with the washer 17, the contact between the fixed contact and the movable contact of the vacuum valve 9 is released, and the vacuum valve 9 is opened.

In this way, when the operating mechanism 2 operates, that is, when the electromagnet operates, a rotational force is generated in the movable iron core 50 around the drive rod 19. If the horizontal cross section of the electromagnet is rectangular rather than circular, a rotational force is generated in the movable iron core 50 when the electromagnet operates, that is, when the movable iron core 50 operates, and the movable iron core 50 may come into contact with the third fixed iron core 53 and coil 16 that are installed on the outer periphery of the movable iron core 50.

Next, the operation mechanism unit 2 described in Example 1 will be described.

Figure 2 is an explanatory diagram illustrating the operation mechanism 2 described in Example 1. Note that Figure 2 is a front view of the operation mechanism 2 shown in Figure 1 as seen from the right side. Figure 2 also shows the open state of the vacuum valve 9.

The operating mechanism 2 has a rectangular horizontal cross section of the electromagnet, and the front width of the operating mechanism 2 (electromagnet) (left-right direction in FIG. 2: longitudinal direction of the electromagnet) is longer than the depth width of the operating mechanism 2 (electromagnet) (depth direction in FIG. 2 (perpendicular to the paper): transverse direction of the electromagnet). The drive rod 19 is installed on the central axis (central part) of this rectangular electromagnet. This allows the installation space for the electromagnet to be used effectively, and the space factor of the electromagnet can be improved.

The use of rectangular electromagnets makes it easier to process the permanent magnets 15. In other words, for example, four linear permanent magnets 15 that are easier to process can be used.

In the first embodiment, the rectangular shape is a rectangle with four right-angled corners, but this rectangular shape may include shapes other than a circle, for example, an ellipse. Also, this rectangular shape is not limited to a rectangle, and may include a triangular shape or a pentagonal shape.

In addition, it is preferable that the corners of a rectangular electromagnet have a radius of curvature. In other words, it is preferable that the corners are formed to have a curvature.

The operating mechanism unit 2 is provided with a rotation-stop member 60 on the first fixed core 51, which prevents the movable core 50 from rotating when the movable core 50 is in operation. The rotation-stop member 60 is installed perpendicular to the first fixed core 51 and parallel to the drive rod 19. The movable core 50 is also provided with a guide groove hole 62 into which the rotation-stop member 60 is inserted (loosely fitted).

The anti-rotation member 60 is attached to the first fixed iron core 51 by welding or screwing. In particular, screw fastening (screw fastening) is preferred, since the anti-rotation member 60 can be easily installed perpendicular to the first fixed iron core 51, in which the anti-rotation member 60 is fastened to the underside of the first fixed iron core 51 by a screw.

In addition, it is preferable to use stainless steel for the anti-rotation member 60, taking into consideration its strength. In other words, it is preferable that the anti-rotation member 60 is made of a material with a higher hardness than the movable iron core 50. The material of the anti-rotation member 60 may also be a magnetic material such as iron.

The diameter of the guide groove 62 is slightly larger than the diameter of the anti-rotation member 60, because the anti-rotation member 60 fits loosely into the guide groove 62 during the closing and opening operations of the vacuum valve 9 by the electromagnet. The length of the guide groove 62 is longer than the length of the anti-rotation member 60. The guide groove 62 may be formed by penetrating the movable iron core 50.

In addition, taking into consideration its strength, it is preferable that the diameter of the anti-rotation member 60 be equal to the diameter of the drive rod 19.

The anti-rotation member 60 is installed on the longitudinal axis of the electromagnet (on the left or right side of the drive rod 19 when viewed from the front of the electromagnet: on the longitudinal axis of the movable iron core 50). In other words, the anti-rotation member 60 is installed so that the line connecting the position where the drive rod 19 is installed (the position on the central axis of the rectangular electromagnet) and the position where the anti-rotation member 60 is installed is parallel to the longitudinal direction of the electromagnet. In other words, the anti-rotation member 60 is installed on a line (on the longitudinal axis of the electromagnet) that passes through the position where the drive rod 19 is installed and is parallel to the longitudinal direction of the electromagnet. The guide groove hole 62 is formed in the movable iron core 50 so as to correspond to the installation position of the anti-rotation member 60. This makes it possible to suppress the rotation of the movable iron core 50 that occurs when the movable iron core 50 operates while maintaining the efficiency of the electromagnet.

The anti-rotation member 60 is preferably installed on the longitudinal axis of the electromagnet (on the longitudinal axis of the movable core 50) closer to the drive rod 19 than half the distance from the position where the drive rod 19 is installed to the longitudinal left or right end position of the movable core 50. In other words, the guide groove hole 62 is also formed at a position closer to the drive rod 19 than half the distance from the position where the drive rod 19 is installed to the longitudinal left or right end position of the movable core 50. This makes it possible to suppress the rotation of the movable core 50 that occurs when the movable core 50 operates while maintaining the efficiency of the electromagnet.

Next, we will explain the vacuum circuit breaker 100 described in Example 1.

Figure 3 is a schematic top view illustrating the vacuum circuit breaker 100 described in Example 1. In Figure 3, the lower side is the front of the vacuum circuit breaker 100.

This vacuum circuit breaker 100 is a three-phase circuit breaker, with a U-phase vacuum valve 9A, a V-phase vacuum valve 9B, and a W-phase vacuum valve 9C installed in a row in the left-right direction in the main circuit opening/closing section 1.

The anti-rotation member 60 is installed in the longitudinal direction of the electromagnet. In other words, it is installed so that the straight line connecting the position where the drive rod 19 is installed and the position where the anti-rotation member 60 is installed is parallel to the longitudinal direction of the electromagnet.

Furthermore, the anti-rotation member 60 is installed in the longitudinal direction of the electromagnet at a position closer to the driving rod 19 than half the distance from the position where the driving rod 19 is installed to the left or right end position in the longitudinal direction of the movable iron core 50.

The operating mechanism 2 described in Example 1 has a rectangular electromagnet, which has a movable iron core 50, a coil 16, a first fixed iron core 51 installed at the bottom of the coil 16, a second fixed iron core 52 installed on the outer periphery of the coil 16, and a third fixed iron core 53 installed at the top of the coil 16. A rotation prevention member 60 that suppresses rotation of the movable iron core 50 is installed on the first fixed iron core 51, and a guide groove hole 62 into which the rotation prevention member 60 is inserted is formed in the movable iron core 50.

This makes it possible to suppress the rotation of the movable core 50 that occurs when the movable core 50 operates while maintaining the efficiency of the electromagnet.

In this way, the operating mechanism 2 described in Example 1 can suppress the rotational force of the movable core 50 around the drive rod 19, which is generated during closing and opening operations by the electromagnet, by using the anti-rotation member 60. This suppresses contact and sliding wear between the movable core 50 and the third fixed core 53 and coil 16 installed on the outer periphery of the movable core 50, reduces the generation of metal dust, and suppresses deformation between the movable core 50 and the third fixed core 53 and coil 16.

Next, the operation mechanism unit 2 described in the second embodiment will be described.

Figure 4 is an explanatory diagram illustrating the operation mechanism unit 2 described in Example 2. Note that Figure 4 is a front view of the operation mechanism unit 2 shown in Figure 1 as seen from the right side. Figure 4 also shows the open state of the vacuum valve 9.

The operation mechanism 2 described in Example 2 is different from the operation mechanism 2 described in Example 1 in the number of anti-rotation members 60 installed. Note that the description of the same parts as in Example 1 will be omitted.

In other words, in Example 1, the anti-rotation member 60 is installed on the left or right side of the drive rod 19 with respect to the front of the electromagnet. On the other hand, in Example 2, the anti-rotation member 60 is installed on the left and right side of the drive rod 19 with respect to the front of the electromagnet. The anti-rotation member 60 is installed on the longitudinal axis of the electromagnet and on the left and right side of the drive rod 19.

In the operating mechanism 2 described in the second embodiment, two anti-rotation members 60 that suppress the rotation of the movable core 50 that occurs when the movable core 50 operates are installed on the first fixed core 51. In addition, the movable core 50 is formed with two guide groove holes 62 into which the two anti-rotation members 60 are inserted, respectively.

The drive rod 19 and the two anti-rotation members 60 are installed so that the straight line connecting the positions where they are installed is parallel to the longitudinal direction of the electromagnet. The guide groove hole 62 is formed in the movable core 50 so as to correspond to the installation positions of the two anti-rotation members 60. In other words, the two anti-rotation members 60 are installed symmetrically (point-symmetrically) with respect to the drive rod 19. This makes it possible to suppress the rotation of the movable core 50 that occurs when the movable core 50 operates while maintaining the efficiency of the electromagnet, and also to evenly distribute the force received by the two anti-rotation members 60, improving the durability of the two anti-rotation members 60.

Next, we will explain the vacuum circuit breaker 100 described in Example 2.

Figure 5 is a schematic top view illustrating the vacuum circuit breaker 100 described in Example 2. In Figure 5, the lower side is the front of the vacuum circuit breaker 100.

The two anti-rotation members 60 are then installed in the longitudinal direction of the electromagnet. In other words, they are installed so that the straight line connecting the position where the drive rod 19 is installed and the position where the two anti-rotation members 60 are installed is parallel to the longitudinal direction of the electromagnet.

Furthermore, the two anti-rotation members 60 are installed in the longitudinal direction of the electromagnet at positions closer to the driving rod 19 than half the distance from the position where the driving rod 19 is installed to the left and right end positions in the longitudinal direction of the movable iron core 50.

In this way, the operating mechanism 2 described in Example 2 can suppress the rotational force of the movable core 50 around the drive rod 19, which occurs during closing and opening operations by the electromagnet, by using the two anti-rotation members 60. This suppresses contact and sliding wear between the movable core 50 and the third fixed core 53 and coil 16 installed on the outer periphery of the movable core 50, reduces the generation of metal dust, and suppresses deformation between the movable core 50 and the third fixed core 53 and coil 16.

The present invention is not limited to the above-mentioned embodiment, but includes various modifications. For example, the above-mentioned embodiment is specifically described in order to explain the present invention in an easily understandable manner, and is not necessarily limited to having all of the configurations described.

It is also possible to replace part of the configuration of one embodiment with part of the configuration of another embodiment. It is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to delete part of the configuration of each embodiment, add part of another configuration, and replace it with part of another configuration.

1...Main circuit opening/closing section, 2...Operation mechanism section, 3...Link mechanism section, 4...Insulating frame, 6...Link mechanism section case, 8...Fixed side conductor, 9, 9A, 9B, 9C...Vacuum valve, 10...Movable side conductor, 11...Flexible conductor, 12...Insulating rod, 13...Contact pressure spring, 14...Connecting plate, 15...Permanent magnet, 16...Coil, 17...Washer, 18...Breakdown spring, 19...Drive rod, 20...Shaft, 21...First pin, 22...First lever, 23...Second pin, 24...Second lever, 25...Press for contact pressure spring 13, 50...Movable core, 51...First fixed core, 52...Second fixed core, 53...Third fixed core, 60...Anti-rotation member, 62...Guide groove, 100...Vacuum circuit breaker.

Claims (9)

The electromagnet has a rectangular horizontal cross section , and a drive rod is disposed on a central axis of the electromagnet.
the electromagnet includes a coil , a movable core that is attached to the driving rod and slides on an inner periphery of the coil , a first fixed core that is attached to a lower portion of the coil, a second fixed core that is attached to an outer periphery of the coil, and a third fixed core that is attached to an upper portion of the coil;
An electromagnetic actuator characterized in that a rotation-prevention member that suppresses rotation of the movable iron core is provided on the first fixed iron core, and a guide groove hole into which the rotation-prevention member is inserted is formed in the movable iron core , the length of the guide groove hole is longer than the length of the rotation-prevention member, and the diameter of the rotation-prevention member is the same as the diameter of the drive rod . 2. The electromagnetic operator according to claim 1,
The electromagnetic actuator is characterized in that the rectangular shape is such that the front width of the electromagnet is longer than the depth width of the electromagnet. 2. The electromagnetic actuator according to claim 1,
The electromagnetic actuator, wherein the anti-rotation member is attached to the first fixed core by screws. 2. The electromagnetic operator according to claim 1,
An electromagnetic actuator, wherein the corners of the rectangular electromagnet have a radius of curvature. 2. The electromagnetic actuator according to claim 1,
The electromagnetic actuator, wherein the anti-rotation member is made of a material having a higher hardness than the movable iron core. 2. The electromagnetic actuator according to claim 1,
An electromagnetic operator, characterized in that the anti-rotation member is installed on a longitudinal axis of the electromagnet. 2. The electromagnetic actuator according to claim 1,
An electromagnetic actuator characterized in that the anti-rotation member is installed on the longitudinal axis of the electromagnet at a position closer to the drive rod than half the distance from the position where the drive rod is installed to the longitudinal end position of the movable iron core. 2. The electromagnetic actuator according to claim 1,
An electromagnetic operator, characterized in that the anti-rotation members are installed on the longitudinal axis of the electromagnet and on the left and right sides of the drive rod. A vacuum circuit breaker having an electromagnetic actuator as described in claim 1.

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