FORM 2
THE PATENTS ACT, 1970 (39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION [See section 10, Rule 13]
ELECTROMAGNETIC OPERATION MECHANISM AND CIRCUIT BREAKER
MITSUBISHI ELECTRIC CORPORATION, A CORPORATION ORGANISED AND
EXISTING UNDER THE LAWS OF JAPAN, WHOSE ADDRESS IS 7-3,
MARUNOUCHI 2-CHOME, CHIYODA-KU, TOKYO 100-8310, JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.

DESCRIPTION
Field
[0001] The present invention relates to an electromagnetic operation mechanism and to a circuit breaker for closing operation that brings a movable contact into contact with a fixed contact and for trip operation that separates the movable contact from the fixed contact.
Background
[0002] One conventionally known circuit breaker for opening and closing an electrical path is an electromagnetic operation circuit breaker. As described in Patent Literature 1, an electromagnetic operation circuit breaker includes an electromagnetic operation mechanism for closing operation or for trip operation, in an electrically insulated housing of a circuit breaker. [0003] The electromagnetic operation mechanism is configured such that excitation of an electromagnetic coil causes the movable iron core that is joined to a drive shaft to be attracted to the fixed iron core. The fixed iron core of the electromagnetic operation mechanism is produced, as described in Patent Literature 2, by stacking one on top of another, and integrating, multiple punched-out magnetic plates.
Citation List
Patent Literature
[0004] Patent Literature 1: Japanese Patent Application
Laid-open No. 2008-159270
Patent Literature 2: Japanese Patent Application Laid-

open No. H06-89808
Summary Technical Problem
[0005] When high power is needed for circuit closure operation in a circuit breaker including an electromagnetic operation mechanism, the electromagnetic operation mechanism is required to output high power, and a large number of stacked magnetic plates is accordingly required. A larger number of stacked magnetic plates may cause a larger variation in the thickness of the fixed iron core, i.e., the length of the fixed iron core in the magnetic plate stacking direction.
[0006] The electromagnetic operation mechanism of a circuit breaker is generally fixed on an electrically insulated housing. In a structure in which the fixed iron core is fixed by placing a screw through a coupling hole formed in the magnetic plate stacking direction as disclosed in Patent Literature 2, variation in the thickness of the fixed iron core may reduce accuracy of the closing operation or of the trip operation.
[0007] For example, a larger variation in the thickness of the fixed iron core may result in a larger variation in the position of the drive shaft, which may in return result in a larger deviation in the position of the link of the transmission mechanism joined to the drive shaft. This may cause a failure in ensuring the amount of movement of the movable contact by the transmission mechanism. In addition, the circuit breaker may become unclosable depending on the situation.
[0008] For a fixed iron core having a greatly varied thickness, one possible solution is to fix the electromagnetic operation mechanism to the housing both in

the magnetic plate stacking direction and in the vertical direction. However, the conventional technology will require a dedicated part or a dedicated structure. This accordingly results in a more complex configuration, and also increases the number of factors in causing variation, which may create a problem similar to the problem arising when the electromagnetic operation mechanism is fixed to the housing in the magnetic plate stacking direction. [0009] The present invention has been made in view of the foregoing, and it is an object of the present invention to provide an electromagnetic operation mechanism capable of reducing or preventing a variation in the position of the drive shaft, and of providing a stable closing operation.
Solution to Problem
[0010] To solve the problem and achieve the object described above, an electromagnetic operation mechanism of the present invention includes a fixed iron core, a movable iron core arranged movable relative to the fixed iron core, an electromagnetic coil fixed to the fixed iron core to generate magnetic flux to move the movable iron core, and a drive shaft joined to the movable iron core. The fixed iron core includes a first divided iron core and a second divided iron core each formed of a stack of multiple first magnetic plates, and facing each other in a direction perpendicular to a stacking direction of the multiple first magnetic plates, and multiple coupling members to join together the first divided iron core and the second divided iron core. The multiple coupling members each include a second magnetic plates having a same shape as the first magnetic sheets to join together the first divided iron core and the second divided iron core in a direction

different from a direction of the first magnetic plates. The second magnetic plate included in at least one of the multiple coupling members projects outward beyond at least one of the first divided iron core or the second divided iron core in a direction perpendicular to the stacking direction, and has a fixing region to be fixed to a support arranged on a housing of a circuit breaker. [0011] The present invention provides an advantage in being capable of reducing or preventing a variation in the position of the drive shaft, and of providing a stable closing operation.
Brief Description of Drawings
[0012] FIG. 1 is a diagram illustrating an example configuration of a circuit breaker according to a first embodiment.
FIG. 2 is an exploded perspective view of the electromagnetic operation mechanism according to the first embodiment.
FIG. 3 is an external perspective view illustrating an assembly of the electromagnetic operation mechanism according to the first embodiment.
FIG. 4 is a plan view of the electromagnetic operation mechanism according to the first embodiment.
FIG. 5 is a side view of the electromagnetic operation mechanism according to the first embodiment.
FIG. 6 is a diagram illustrating an example configuration of the magnetic plate according to the first embodiment.
FIG. 7 is an illustrative diagram of a method of coupling together a first divided iron core and a second divided iron core by means of a first coupling member, a second coupling member, a third coupling member, and a

fourth coupling member according to the first embodiment.
FIG. 8 is a diagram illustrating a situation in which the electromagnetic operation mechanism is fixed to the support protruding from the partition wall of the housing according to the first embodiment.
FIG. 9 is a diagram illustrating an example configuration of a magnetic plate that forms a fixed iron core of an electromagnetic operation mechanism according to a second embodiment.
FIG. 10 is a plan view of the electromagnetic operation mechanism according to the second embodiment.
FIG. 11 is a diagram illustrating a situation in which the electromagnetic operation mechanism is fixed to the supports protruding from the partition wall of the housing according to the second embodiment.
FIG. 12 is a plan view of the electromagnetic operation mechanism having another configuration according to the second embodiment.
Description of Embodiments [0014] First embodiment.
FIG. 1 is a view illustrating an exemplary configuration of the circuit breaker according to the first embodiment. The circuit breaker according to the first embodiment is, for example, an air circuit breaker that opens and closes an electric circuit in the atmosphere, but can also be applied to a circuit breaker other than the air circuit breaker. The following drawings contain an XYZ axis coordinate system for convenience of explanation. In the XYZ axis coordinate system, the positive Z-axis direction is regarded as upward, the negative Z-axis direction is regarded as downward, the positive X-axis direction is regarded as right, the negative X-axis

direction is regarded as left, the positive Y-axis direction is regarded as front, and the negative Y-axis direction is regarded as rear.
[0015] As illustrated in FIG. 1, a circuit breaker 100 according to the first embodiment includes an insulating housing 1, a first fixed conductor 10, a second fixed conductor 11, a mover 20, and a flexible conductor 30. The first fixed conductor 10 is connected to a power supply side conductor (not illustrated). The second fixed conductor 11 is connected to a load side conductor (not illustrated). The mover 20 includes a movable contact 20a. The flexible conductor 30 electrically connects the second fixed conductor 11 and the mover 20 and has flexibility. [0016] A first space 7 and a second space 8 separated by a partition wall 3 are formed inside the housing 1. The first fixed conductor 10 is also referred to as a power supply side terminal, and penetrates a wall 2 of the housing 1 from the outside of the housing 1 to the first space 7. One end 101 of the first fixed conductor 10 protrudes out of the housing 1 and is connected to the power supply side conductor (not illustrated). The other end 102 of the first fixed conductor 10 is placed in the first space 7, and a fixed contact 10a is fixed to the other end 102.
[0017] The second fixed conductor 11 is also referred to as a load side terminal, and penetrates the wall 2 of the housing 1 from the outside of the housing 1 to the first space 7, similarly to the first fixed conductor 10. One end 111 of the second fixed conductor 11 protrudes out of the housing 1 and is connected to the load side conductor (not illustrated). The other end 112 of the second fixed conductor 11 is placed in the first space 7. [0018] The movable contact 20a is provided at one end

201 of the mover 20. One end 301 of the flexible conductor 30 is fixed to the other end 202 of the mover 20. The other end 302 of the flexible conductor 30 is fixed to the other end 112 of the second fixed conductor 11.
[0019] The circuit breaker 100 also includes a contact pressure spring 41 and a link pin 42. One end of the contact pressure spring 41 is attached to the other end 202 of the mover 20, and the other end of the contact pressure spring 41 is attached to the wall 2 of the housing 1. The link pin 42 is attached to the mover 20. The contact pressure spring 41 urges and rotates the mover 20 about the link pin 42 such that the movable contact 20a approaches the fixed contact 10a, and applies a contact pressure between the fixed contact 10a and the movable contact 20a when the movable contact 20a provided on the mover 2 0 is connected to the fixed contact 10a.
[0020] The circuit breaker 100 includes a transmission unit 50, an electromagnetic operation mechanism 60, and a coupling unit 7 0. The transmission unit 50 is coupled to the mover 20 by the link pin 42. The electromagnetic operation mechanism 60 moves the mover 20 via the transmission unit 50. The coupling unit 7 0 couples the transmission unit 50 and the electromagnetic operation mechanism 60. Note that the transmission unit 50 is placed across the first space 7 and the second space 8, and the electromagnetic operation mechanism 60 and the coupling unit 70 are placed in the second space 8.
[0021] The transmission unit 50 includes an operation arm 51, a coupling plate 52, and a shaft 54. The operation arm 51 is rotatably coupled at one end 511 to the mover 20 by the link pin 42. The coupling plate 52 is rotatably coupled at one end 521 to the other end 512 of the operation arm 51 by a link pin 53. The shaft 54 is fixed

in the middle of the coupling plate 52 and rotates about a shaft center 55.
[0022] Note that the transmission unit 50 is not limited to the configuration described above. For example, the transmission unit 50 may be configured such that the mover 20 is coupled to the distal end of one rotating member that rotates about the shaft center 55. The transmission unit 50 may also include one or more link members between the operation arm 51 and the coupling plate 52.
[0023] The electromagnetic operation mechanism 60 is placed below the coupling plate 52, and fixed to supports 4 and 5 protruding from the partition wall 3 of the housing 1 toward the second space 8. A drive shaft 65 of the electromagnetic operation mechanism 60 is coupled to the other end 522 of the coupling plate 52 via the coupling unit 7 0 at a position spaced predefined distance with respect to the shaft center 55 of the shaft 54.
[0024] The coupling unit 70 includes coupling pins 71 and 72 and a coupling link 73. The coupling pin 71 passes through one coupling hole (not illustrated) formed in the coupling link 7 3 and a coupling hole 67 formed in the drive shaft 65. The coupling pin 72 passes through the other coupling hole (not illustrated) formed in the coupling link 7 3 and a coupling hole (not illustrated) formed in the middle of the coupling plate 52.
[0025] Here, closing operation, which is the operation of moving the movable contact 20a into contact with the fixed contact 10a, will be described. As illustrated in FIG. 1, in the tripped state of the circuit breaker 100 in which the movable contact 20a is separated from the fixed contact 10a, when the drive shaft 65 of the electromagnetic operation mechanism 60 moves upward, the coupling plate 52 coupled to the drive shaft 65 via the coupling unit 70 is

driven via the coupling unit 7 0 to rotate about the shaft center 55 in the direction that lowers the one end 521.
[0026] As the shaft 54 rotates in the direction that lowers the one end 521, the operation arm 51 is driven by the coupling plate 52 via the link pin 53 so as to be linearly arranged in the length direction of the coupling plate 52. When the operation arm 51 is driven, the mover 20 moves toward the wall 2 while compressing the contact pressure spring 41, and the movable contact 20a comes into contact with the fixed contact 10a.
[0027] After the movable contact 20a comes into contact with the fixed contact 10a, the contact pressure spring 41 causes the mover 20 to pivot around the link pin 42 in the direction that brings the movable contact 20a close to the fixed contact 10a. Thus, a contact pressure is applied between the fixed contact 10a and the movable contact 20a, and the circuit breaker 100 is put into the closed state. When the circuit breaker 100 is in the closed state, the first fixed conductor 10 is electrically connected to the second fixed conductor 11 via the fixed contact 10a, the movable contact 20a, the mover 20, and the flexible conductor 30.
[0028] The circuit breaker 100 includes a holding mechanism (not illustrated). The closed state is held by the above-mentioned holding mechanism. By releasing the closed state held by the holding mechanism, each member operates in the reverse direction to the closing action, and the movable contact 20a is positioned away from the fixed contact 10a to be in the tripped state illustrated in FIG. 1.
[0029] As described above, the circuit breaker 100 according to the first embodiment performs closing operation to shift from the tripped state to the closed

state through the upward movement of the drive shaft 65 of the electromagnetic operation mechanism 60.
[0030] Hereinafter, the configuration of the electromagnetic operation mechanism 60 will be described in detail. FIG. 2 is an exploded perspective view of the electromagnetic operation mechanism according to the first embodiment. FIG. 3 is an external perspective view illustrating the electromagnetic operation mechanism according to the first embodiment in an assembled state. FIG. 4 is a plan view of the electromagnetic operation mechanism according to the first embodiment. FIG. 5 is a side view of the electromagnetic operation mechanism according to the first embodiment. Note that FIGS. 1 to 5 contain an XYZ axis coordinate system such that the state of the electromagnetic operation mechanism 60 in FIG. 1 represents a front view of the electromagnetic operation mechanism 60.
[0031] As illustrated in FIGS. 2 and 3, the electromagnetic operation mechanism 60 includes a fixed iron core 61, a cylindrical electromagnetic coil 62, an insulating bobbin 63, a movable iron core 64, the drive shaft 65, and a guide member 66. The electromagnetic coil 62 is fixed to the fixed iron core 61. The electromagnetic coil 62 is wound on the bobbin 63. The movable iron core 64 is inserted into the inner space of the bobbin 63. The drive shaft 65 is coupled to the movable iron core 64. The guide member 66 guides the vertical movement of the drive shaft 65.
[0032] As illustrated in FIG. 2, the fixed iron core 61 includes an inner space 68. The electromagnetic coil 62 and the bobbin 63 are arranged in the inner space 68 of the fixed iron core 61. The coupling hole 67 is formed in one end 651 of the drive shaft 65. Using the coupling hole 67,

the drive shaft 65 is coupled to the other end 522 of the coupling plate 52 illustrated in FIG. 1. The other end 652 of the drive shaft 65 is fixed to the movable iron core 64.
[0033] When an excitation current is supplied to the electromagnetic coil 62, the electromagnetic coil 62 generates a magnetic flux. Due to the action of the magnetic flux from the electromagnetic coil 62, the movable iron core 64 is attracted to the fixed iron core 61, moves upward, touches a first inner wall 611 and a second inner wall 612 of the fixed iron core 61 illustrated in FIGS. 2 and 4, and stops. As the fixed iron core 61 moves upward, the drive shaft 65 moves upward.
[0034] A third inner wall 613 and a fourth inner wall 614 of the fixed iron core 61 illustrated in FIG. 2 are configured to touch the middle portion of the movable iron core 64 in the tripped state illustrated in FIG. 1 to keep the movable iron core 64 stationary. Note that the shape of the third inner wall 613 and the fourth inner wall 614 is not limited to the shape illustrated in FIG. 2. Any shape may be employed as long as the third inner wall 613 and the fourth inner wall 614 touch the movable iron core 64 and keep the movable iron core 64 stationary.
[0035] The fixed iron core 61 includes a first divided iron core 81, a second divided iron core 82, a first coupling member 83, a second coupling member 84, a third coupling member 85, and a fourth coupling member 86. The first divided iron core 81 and the second divided iron core 82 each include a plurality of magnetic plates 90 stacked in the same direction. The first divided iron core 81 and the second divided iron core 82 face each other. The first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86 each include one or more magnetic plates 91 and couple the

first divided iron core 81 and the second divided iron core 82. In the first divided iron core 81 and the second divided iron core 82, the plurality of magnetic plates 90 stacked are integrated by swage, adhesion, or welding.
[0036] The magnetic plate 90 and the magnetic plate 91 have the same shape, and are formed, for example, by die-cutting a magnetic plate such as a silicon steel plate. The magnetic plate 90 is an example of a first magnetic plate, and the magnetic plate 91 is an example of a second magnetic plate. FIG. 6 is a view illustrating an exemplary configuration of a magnetic plate according to the first embodiment. In FIG. 6, the upward direction is the positive Z-axis direction, the downward direction is the negative Z-axis direction, and the right direction is the positive X-axis direction.
[0037] As illustrated in FIG. 6, each of the magnetic plates 90 and 91 includes an extension 92, a first protrusion 93, and a second protrusion 94. The extension
92 extends in the vertical direction. The first protrusion
93 protrudes rightward from the upper portion of the extension 92. The second protrusion 94 protrudes rightward from the lower portion of the extension 92. A plurality of coupling holes 95a, 95b, 95c, 95d, and 95e are formed in the extension 92 along the vertical direction. The first protrusion 93 includes a coupling hole 95f at the distal end. Hereinafter, the coupling holes 95a, 95b, 95c, 95d, 95e, and 95f may be referred to as coupling holes 95 collectively.
[0038] The coupling hole 95e is farther from the coupling hole 95a than the coupling hole 95d is. The distance LI between the coupling hole 95a and the coupling hole 95e is longer than the distance L2 between the coupling hole 95a and the coupling hole 95d. An end 911 of

the magnetic plate 91 illustrated in FIG. 6 is used for fixing to the housing 1 as will be described later. The outer size of the electromagnetic operation mechanism 60 varies depending on the performance required of the electromagnetic operation mechanism 60. Therefore, the length of the distance L2 can be freely set in accordance with the outer size under the constraint that coupling holes 95 are aligned when the magnetic plate 90 and the magnetic plate 91 in different orientations overlap each other.
[0039] In the following example, the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86 each include one magnetic plate 91. Alternatively, each coupling member may include a plurality of magnetic plates 91 stacked in the same direction. In the example illustrated in FIGS. 2, 3, 4, and 5, the first divided iron core 81 and the second divided iron core 82 each include 19 magnetic plates 90 stacked. However, the number of magnetic plates 90 stacked may be 18 or less or may be 20 or more.
[004 0] The first protrusion 93 and the second protrusion 94 of the magnetic plate 90 may also be referred to as the first protrusion 93 and the second protrusion 94 of the first divided iron core 81, and the first protrusion 93 and the second protrusion 94 of the magnetic plate 90 may also be referred to as the first protrusion 93 and the second protrusion 94 of the second divided iron core 82. The same applies to the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86.
[0041] In the assembled state of the electromagnetic operation mechanism 60, the first divided iron core 81 and

the second divided iron core 82 are arranged mirror-symmetrically, and face each other in the protruding direction of the first protrusion 93 and the second protrusion 94.
[0042] The guide member 66 illustrated in FIG. 2 is placed between the first protrusion 93 of the first divided iron core 81 and the first protrusion 93 of the second divided iron core 82. The guide member 66 includes a guide hole 69 through which the drive shaft 65 is inserted. The guide member 66 is sandwiched between the first protrusion 93 of the first divided iron core 81 and the first protrusion 93 of the second divided iron core 82.
[0043] As illustrated in FIG. 5, the first divided iron core 81 and the second divided iron core 82 are coupled by the first coupling member 83 and the second coupling member 84 on one end side in the stacking direction of the magnetic plates 90, and coupled by the third coupling member 85 and the fourth coupling member 86 on the other end side in the stacking direction of the magnetic plates 90. The first divided iron core 81 and the second divided iron core 82 are coupled by fixing the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86 to the first divided iron core 81 and the second divided iron core 82 with coupling bolts 87a, 87b, 87c, 87d, 87e, and 87f.
[0044] FIG. 7 is a view for explaining a method of coupling the first divided iron core 81 and the second divided iron core 82 using the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 8 6 according to the first embodiment. For convenience of explanation, the electromagnetic coil 62, the bobbin 63, the movable iron

core 64, and the drive shaft 65 are not illustrated in FIG.
7.
[0045] As illustrated in FIG. 7, the first divided iron
core 81 and the second divided iron core 82 are arranged
such that the first protrusions 93 face each other and the
second protrusions 94 face each other. In this state, the
first divided iron core 81 and the second divided iron core
82 are mirror-syirunetric.
[0046] That is, the first protrusion 93 of the first divided iron core 81 and the first protrusion 93 of the second divided iron core 82 face each other with a gap therebetween, and the second protrusion 94 of the first divided iron core 81 and the second protrusion 94 of the second divided iron core 82 face each other with a gap therebetween. The space surrounded by the first divided iron core 81 and the second divided iron core 82 is the inner space 68 described above. The drive shaft 65 protrudes out of the fixed iron core 61 through the gap formed by the first protrusion 93 of the first divided iron core 81 and the first protrusion 93 of the second divided iron core 82.
[0047] The first protrusions 93 of the first coupling member 83 and the second coupling member 84 face each other, and the second protrusions 94 of the first coupling member
83 and the second coupling member 84 face each other. The
orientation of the magnetic plates 90 constituting the
first coupling member 83 and the second coupling member 84
is different from the orientation of the magnetic plates 90
constituting the first divided iron core 81 and the second
divided iron core 82. Specifically, the orientation of the
first coupling member 83 is rotated 90 degrees with respect
to the orientation of the magnetic plates 90 constituting
the first divided iron core 81 along the XZ-plane, which is

the stacking plane of the magnetic plates 90, in the direction in which the X-axis approaches the Z-axis. The orientation of the second coupling member 84 is rotated 90 degrees with respect to the orientation of the magnetic plates 90 constituting the second divided iron core 82 along the XZ-plane in the direction in which the X-axis approaches the Z-axis.
[004 8] Similarly, the first protrusions 93 of the third coupling member 85 and the fourth coupling member 86 face each other, and the second protrusions 94 of the third coupling member 85 and the fourth coupling member 86 face each other. The orientation of the magnetic plates 90 constituting the third coupling member 85 and the fourth coupling member 86 is different from the orientation of the magnetic plates 90 constituting the first divided iron core 81 and the second divided iron core 82.
[004 9] The first coupling member 83 and the second coupling member 84 are arranged to respectively face the third coupling member 85 and the fourth coupling member 86 via the first divided iron core 81 and the second divided iron core 82.
[0050] Consequently, the plate surfaces of the first coupling member 83 and the second coupling member 84 overlap the plate surface of the uppermost magnetic plate 90 of the plurality of magnetic plates 90 stacked as each of the first divided iron core 81 and the second divided iron core 82. The plate surfaces of the third coupling member 85 and the fourth coupling member 8 6 overlap the plate surface of the lowermost magnetic plate 90 of each of the first divided iron core 81 and the second divided iron core 82.
[0051] Using the coupling bolts 87a, 87b, 87c, 87d, 87e, and 87f and nuts 88a, 88b, 88c, 88d, 88e, and 88f, the

first divided iron core 81 and the second divided iron core 82 are fixed to the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86. For example, the coupling bolt 87a is inserted into the coupling hole 95a of the first coupling member 83, the coupling hole 95e of the first divided iron core 81, and the coupling hole 95a of the third coupling member 85 and fixed by the nut 88a. Similarly, the coupling bolts 87b, 87c, 87d, 87e, and 87f are inserted into the corresponding coupling holes 95 and fastened by the nuts 88b, 88c, 88d, 88e, and 88f, respectively. Consequently, the first divided iron core 81 and the second divided iron core 82 are coupled by the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86.
[0052] In this manner, by using a plurality of magnetic plates 91 having the same shape as and arranged in a different orientation from the plurality of magnetic plates 90 stacked in the first coupling member 83 and the second coupling member 84, the first coupling member 83 and the second coupling member 84 can be fixed. Therefore, the fixed iron core 61 can be configured using one type of magnetic plate, and the number of types of components constituting the fixed iron core 61 can be reduced significantly, as compared with the case where a plurality of types of magnetic plates are used.
[0053] As illustrated in FIGS. 3, 4, and 7, the coupling holes 95a, 95e, and 95f of the coupling holes 95a, 95b, 95c, 95d, 95e, and 95f formed in the magnetic plates 90 for forming the first divided iron core 81 and the second divided iron core 82 are used for fixing the first coupling member 83, the second coupling member 84, the third

coupling member 85, and the fourth coupling member 86. The coupling holes 95a, 95b, 95c, and 95d of the plurality of coupling holes 95a, 95b, 95c, 95d, 95e, and 95f formed in the magnetic plates 91 for forming the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86 are used for coupling the first divided iron core 81 and the second divided iron core 82.
[0054] In this manner, the first divided iron core 81 and the second divided iron core 82 share the coupling holes 95a with the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86. Consequently, the number of coupling holes 95 formed in the magnetic plates 90 and 91 can be reduced, and a decrease in the strength of the magnetic plates 90 and 91 can be prevented. Although the magnetic plates 90 and 91 described above include the six coupling holes 95a, 95b, 95c, 95d, 95e, and 95f, the number of coupling holes 95 is not limited to six.
[0055] As illustrated in FIG. 3, at least ends 831, 841, 851, and 8 61 of the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86 protrude outward from the first divided iron core 81 and the second divided iron core 82 in the negative Y-axis direction orthogonal to the stacking direction of the magnetic plates 90 of the first divided iron core 81 and the second divided iron core 82. The coupling holes 95e are formed in the ends 831, 841, 851, and 861. Each of the ends 831, 841, 851, and 861 is the end 911 of the magnetic plate 91 illustrated in FIG. 6.
[0056] As illustrated in FIG. 4, the electromagnetic operation mechanism 60 is configured such that the first divided iron core 81 and the second divided iron core 82

are coupled by the coupling holes 95a and 95d the distance between which is shorter than the distance LI between the coupling holes 95a and 95e in the magnetic plate 91. Therefore, the ends 831, 841, 851, and 861 can protrude in the negative X-axis direction from the first divided iron core 81 and the second divided iron core 82.
[0057] The coupling hole 95e formed in the magnetic plate 90 constituting each of the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 8 6 is used for fixing the electromagnetic operation mechanism 60 to the support 4 and the support 5 protruding from the partition wall 3 of the housing 1 toward the second space 8. The variation in the distance L3 between the central axis 01 of the drive shaft 65 and the coupling hole 95e of the magnetic plate 91 does not depend on the thickness of the first divided iron core 81 and the second divided iron core 82, which can reduce variation in the position of the central axis 01 of the drive shaft 65 in the housing 1. Hereinafter, this point will be described in detail.
[0058] FIG. 8 is a view illustrating how the electromagnetic operation mechanism is fixed to the supports protruding from the partition wall of the housing according to the first embodiment. The supports 4 and 5 are, for example, ribs protruding from the partition wall 3 but may be metal members attached to the partition wall 3 such as L-shaped metal fittings fixed to the partition wall 3.
[0059] As illustrated in FIG. 8, the first coupling member 83 is fixed to the housing 1 by screwing a mounting screw 9 6 into the screw hole formed in the support 4 through the coupling hole 95e of the first coupling member 83. The second coupling member 84 is fixed to the housing

1 by screwing a mounting screw 97 into the screw hole formed in the support 5 through the coupling hole 95e of the second coupling member 84. The plate surfaces of the magnetic plates 91 constituting the first coupling member 83 and the second coupling member 84, that is, the surfaces of the magnetic plates 91 in the stacking direction, are fixing regions that are fixed to the supports 4 and 5, and fixed to the supports 4 and 5 as mounting surfaces for the supports 4 and 5.
[0060] Similarly, a mounting screw (not illustrated) is screwed into the screw hole formed in a rib {not illustrated) through the coupling hole 95e of the third coupling member 85, whereby the third coupling member 85 is fixed to the housing 1. A mounting screw (not illustrated) is screwed into the screw hole formed in a rib (not illustrated) through the coupling hole 95e of the fourth coupling member 86, whereby the fourth coupling member 86 is fixed to the housing 1. In the described example, the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 8 6 are attached to the ribs. Alternatively, only some of the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86 may be attached to the ribs.
[0061] The variation in the distance L4 between the central axis 01 of the drive shaft 65 and the partition wall 3 is determined by the variation in the outer shape of the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 8 6 and the variation in the position of the coupling hole 95e. Therefore, an increase in the size of the electromagnetic operation mechanism 60 does not affect the number of magnetic plates 90 stacked to constitute the

first divided iron core 81 and the second divided iron core 82.
[0062] Thus, the electromagnetic operation mechanism 60 can be fixed with a small variation in the position of the central axis 01 of the drive shaft 65 from the partition wall 3 of the housing 1, as compared with the case where the first divided iron core 81 and the second divided iron core 82 are fixed in the stacking direction of the magnetic plates 90. Consequently, the positional relationship between the other components coupled to the drive shaft 65 is stabilized, and stable closing action can be performed.
[0063] Since the electromagnetic operation mechanism 60 can be fixed to the housing 1 using the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86 that couple the first divided iron core 81 and the second divided iron core 82, a different member for fixing the electromagnetic operation mechanism 60 to the housing 1 is not required. Therefore, the number of components of the circuit breaker 100 can be reduced.
[0064] The coupling holes 95e in the first divided iron core 81 and the second divided iron core 82 which are used for coupling the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 8 6 can also be used for fixing to the housing 1. Therefore, the number of coupling holes 95 formed in the magnetic plates 90 and 91 can be reduced, and a decrease in the strength of the magnetic plates 90 and 91 can be prevented.
[0065] As described above, the circuit breaker 100 according to the first embodiment includes the first fixed conductor 10, which is an example of a fixed conductor including the fixed contact 10a, the mover 20 including the

movable contact 20a, the electromagnetic operation mechanism 60 that includes the drive shaft 65 and moves the drive shaft 65 linearly, the transmission unit 50 that moves the mover 20 in accordance with the movement of the drive shaft 65 to bring the movable contact 20a into contact with and away from the fixed contact 10a, and the housing 1 that covers the electromagnetic operation mechanism 60 and the transmission unit 50. The electromagnetic operation mechanism 60 includes the fixed iron core 61, the movable iron core 64 provided movably with respect to the fixed iron core 61, the electromagnetic coil 62 that is fixed to the fixed iron core 61 and generates a magnetic flux to move the movable iron core 64, and the drive shaft 65 coupled to the movable iron core 64. [0066] The fixed iron core 61 includes the first divided iron core 81 and the second divided iron core 82 each including a plurality of magnetic plates 90 stacked. Each magnetic plate 90 is an example of the first magnetic plate. The first divided iron core 81 and the second divided iron core 82 face each other in a direction orthogonal to the stacking direction of the plurality of magnetic plates 90. The fixed iron core 61 also includes the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86 coupling the first divided iron core 81 and the second divided iron core 82. Each of the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86 includes the magnetic plate 91 having the same shape as the magnetic plates 90. The magnetic plate 91 is an example of the second magnetic plate. The magnetic plate 91 couples the first divided iron core 81 and the second divided iron core 82 in an orientation different from the orientation of the magnetic

plates 90. The magnetic plate 91 constituting at least one of the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 83 protrudes outward from at least one of the first divided iron core 81 and the second divided iron core 82 in a direction orthogonal to the stacking direction of the plurality of magnetic plates 90, and has a fixing region that is fixed to the support 4 or 5 provided in the housing 102.
[0067] Therefore, the variation in the position of the central axis 01 of the drive shaft 65 is determined by the variation in the outer shape of the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 8 6 and the variation in the position of the coupling hole 95e. Therefore, an increase in the size of the electromagnetic operation mechanism 60 does not affect the number of magnetic plates 90 stacked to constitute the first divided iron core 81 and the second divided iron core 82. Thus, the electromagnetic operation mechanism 60 can be fixed with a small variation in the position of the central axis 01 of the drive shaft 65, as compared with the case where the first divided iron core 81 and the second divided iron core 82 are fixed in the stacking direction of the magnetic plates 90. Consequently, the positional relationship between the other components coupled to the drive shaft 65 is stabilized, and stable closing action can be performed. Since the magnetic plates 90 and 91 constituting the fixed iron core 61 have the same shape, the number of types of components constituting the fixed iron core 61 can be reduced.
[0068] The magnetic plate 91 is fixed to the support 4 or 5 using the surface of the end 911 in the stacking

direction of the magnetic plates 90 as a mounting surface for the support 4 or the support 5. Accordingly, the magnetic plate 91 can be fixed to the support 4 or 5 by surface contact, and the electromagnetic operation mechanism 60 can be attached to the housing 1 stably. Note that the side of the end 911 may be used, in place of the surface of the end 911, as a fixing region that is fixed to the support 4 or the support 5.
[0069] The moving direction of the movable iron core 64 is a direction orthogonal to the stacking direction of the magnetic plates 90. The end 911 of the magnetic plate 91 protrudes outward from at least one of the first divided iron core 81 and the second divided iron core 82 in a direction orthogonal to both the stacking direction of the magnetic plates 90 and the moving direction of the movable iron core 64. Therefore, the length of the fixed iron core 61 in the moving direction of the movable iron core 64 can be reduced, and the length of the electromagnetic operation mechanism 60 excluding the drive shaft 65 can be reduced in the moving direction of the movable iron core 64. [0070] The magnetic plate 90 and the magnetic plate 91 each include the plurality of coupling holes 95a, 95b, 95c, 95d, 95e, and 95f, and the coupling hole 95e of the plurality of coupling holes 95a, 95b, 95c, 95d, 95e, and 95f is formed in the end 911. Consequently, a fastener such as a bolt can be attached to the coupling hole 95e formed in the end 911 of the magnetic plate 91, and the end 911 can be easily fixed to the support 4 or 5. [0071 ] One or more coupling holes 95 of the plurality of coupling holes 95a, 95b, 95c, 95d, 95e, and 95f are selectively used for coupling the magnetic plates 91 to the magnetic plates 90 of the first divided iron core 81 and the second divided iron core 82 and for fixing the magnetic

plates 91 to the support 4 and the support 5. Consequently, the number of coupling holes 95 formed in the magnetic plates 90 and 91 can be reduced, and a decrease in the strength of the magnetic plates 90 and 91 can be prevented.
[0072] Second Embodiment.
In the example described in the first embodiment, the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 8 6 partially protrude in a direction orthogonal to the central axis 01 of the drive shaft 65 to be fixed to the supports 4 and 5 of the housing 1. A second embodiment is different from the first embodiment in that the first coupling member 83, the second coupling member 84, the third coupling member 85, and the fourth coupling member 86 partially protrude in the direction along the central axis 01 of the drive shaft to be fixed to the supports 4 and 5 of the housing 1.
[007 3] In the following description, components having the same functions as those in the first embodiment are denoted by the same reference signs, and descriptions thereof are omitted. The difference from the electromagnetic operation mechanism 60 according to the first embodiment is mainly described. Members having the same functions as those constituting the electromagnetic operation mechanism 60 according to the first embodiment are described using the reference signs that are the same as those in the first embodiment except that the sing "A" is added to the reference signs.
[0074] FIG. 9 is a view illustrating an exemplary configuration of a magnetic plate constituting the fixed iron core of the electromagnetic operation mechanism according to the second embodiment. FIG. 10 is a plan view of the electromagnetic operation mechanism according to the

second embodiment. In FIG. 9, the upward direction is the positive Z-axis direction, the downward direction is the negative Z-axis direction, and the right direction is the positive X-axis direction.
[0075] An electromagnetic operation mechanism 60A according to the second embodiment uses magnetic plates 90A and 91A having a shape different from the shape of the magnetic plates 90 and 91 according to the first embodiment. As illustrated in FIG. 9, the magnetic plates 90A and 91A have the same shape, similarly to the magnetic plates 90 and 91. Each of the magnetic plates 90A and 91A includes an extension 92A, a first protrusion 93A, and a second protrusion 94A. The extension 92A extends in the vertical direction. The first protrusion 93A protrudes rightward from the upper portion of the extension 92A. The second protrusion 94A protrudes rightward from the lower portion of the extension 92A. Coupling holes 98a, 98b, 98c, 98d, 98e, and 98f are formed in the extension 92A, and a coupling hole 98g is formed in the first protrusion 93A. Hereinafter, the coupling holes 98a, 98b, 98c, 98d, 98e, 98f, and 98g may be referred to as coupling holes 98A collectively.
[0076] As illustrated in FIG. 10, a fixed iron core 61A includes a first divided iron core 81A, a second divided iron core 82A, a first coupling member 83A, a second coupling member 84A, a third coupling member 85A, and a fourth coupling member 86A. The first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 8 6A are fixed to the first divided iron core 81A and the second divided iron core 82A by coupling bolts 87a, 87b, 87c, 87d, 87e, and 87f. The first divided iron core 81A and the second divided iron core 82A are formed by the magnetic plates 90A. The first

coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 86A are formed by the magnetic plates 91A. In FIG. 10, the third coupling member 85A and the fourth coupling member 86A are hidden by the first coupling member 83A and the second coupling member 84A and are not illustrated.
[0077] In the example illustrated in FIG. 10, the coupling holes 98a, 98e, and 98g of the coupling holes 98a, 98b, 98c, 98d, 98e, 98f, and 98g in the magnetic plates 90A are used for fixing the first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 86A. The coupling holes 98b, 98c, 98d, and 94f of the plurality of coupling holes 98a, 98b, 98c, 98d, 98e, 98f, and 98g formed in the magnetic plates 91A are used for coupling the first divided iron core 81A and the second divided iron core 82A. Although the magnetic plates 90A and 91A include the seven coupling holes 98A, the number of coupling holes 98A is not limited to the number illustrated in FIG. 9, as in the case of the magnetic plates 90 and 91.
[0078] As illustrated in FIG. 10, at least ends 832A and 842A of the first coupling member 83A and the second coupling member 84A protrude outward from the first divided iron core 81A and the second divided iron core 82A in the vertical direction, which is a direction orthogonal to the stacking direction of the magnetic plates 90A of the first divided iron core 81A and the second divided iron core 82A. Similarly, ends (not illustrated) of the third coupling member 85A and the fourth coupling member 86A also protrude outward from the first divided iron core 81A and the second divided iron core 82A in the vertical direction. Each of the ends 832A and 842A is an end 291b of the magnetic plate 91A illustrated in FIG. 9.

[007 9] The coupling holes 98a and 98e formed in the magnetic plate 90A constituting each of the first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 86A are used for fixing the electromagnetic operation mechanism 60A to supports 4 and 5 protruding from a partition wall 3 of a housing 1. FIG. 11 is a diagram illustrating how the electromagnetic operation mechanism is fixed to the supports protruding from the partition wall of the housing according to the second embodiment.
[0080] As illustrated in FIG. 11, the first coupling member 83A is fixed to the housing 1 by screwing a mounting screw 9 6 into the screw hole formed in the support 4 through the coupling hole 98e of the first coupling member 83A. The second coupling member 84A is fixed to the housing 1 by screwing a mounting screw 97 into the screw hole formed in the support 5 through the coupling hole 98e of the second coupling member 84A. Similarly, the third coupling member 85A and the fourth coupling member 86A are fixed to the supports 4 and 5 by mounting screws (not illustrated). The plate surfaces of the magnetic plates 91A constituting the first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 8 6A, that is, the surfaces of the magnetic plates 91A in the stacking direction, are fixed to the supports 4 and 5 as mounting surfaces for the supports 4 and 5.
[0081] The variation in the distance L5 between the central axis 01 of a drive shaft 65 and the partition wall 3 is determined by the variation in the outer shape of the first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 8 6A and the variation in the position of the

coupling hole 98e. Therefore, an increase in the size of the electromagnetic operation mechanism 60A does not affect the number of magnetic plates 90A stacked to constitute the first divided iron core 81A and the second divided iron core 82A.
[0082] In the described example, the electromagnetic operation mechanism 60A is fixed to the housing 1 using the coupling holes 98e in the first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 86A. Alternatively, the electromagnetic operation mechanism 60A may be fixed to the housing 1 using only some of the coupling holes 98e in the first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 86A. The electromagnetic operation mechanism 60A can be fixed to the housing 1 using all of the coupling holes 98e in the first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 8 6A.
[0083] In the above-described example, the first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 86A partially protrude upward or downward from the first divided iron core 81A and the second divided iron core 81A. Alternatively, the configuration may be such that some coupling members of the first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 8 6A do not protrude upward or downward. FIG. 12 is a plan view illustrating another configuration of the electromagnetic operation mechanism according to the second embodiment. For example, as illustrated in FIG. 12, the second coupling member 84A and the fourth coupling member 86A may be fixed to the first

divided iron core 81A and the second divided iron core 82A such that the second coupling member 84A and the fourth coupling member 8 6A do not protrude upward or downward. FIG. 12 is a plan view of the electromagnetic operation mechanism having another configuration according to the second embodiment.
[0084] As described above, in the electromagnetic operation mechanism 60A according to the second embodiment, the end 912A of the magnetic plate 91A constituting one of the first coupling member 83A, the second coupling member 84A, the third coupling member 85A, and the fourth coupling member 86A protrudes outward from at least one of the first divided iron core 81A and the second divided iron core 82A in a direction orthogonal to the stacking direction of the plurality of magnetic plates 90A of the first divided iron core 81A and the second divided iron core 82A, and has a fixing region that is fixed to the support 4 or 5 provided in the housing 1. The protruding direction of the end 912A of the magnetic plate 91A is the moving direction of a movable iron core 64. Therefore, the length of the fixed iron core 61A can be reduced in the width direction, which is a direction orthogonal to both the moving direction of the movable iron core 64 and the stacking direction of the magnetic plates 90A, and the length of the electromagnetic operation mechan Jsn 60A car: be reduced J. n the wJ. dth direction.
[0085] In the above-described examples, the protruding ends 911 and 912 of the magnetic plates 91 and 91A are fixed to the supports 4 and 5. However, the ends 911 and 912 need not necessarily be fixed to the supports 4 and 5 as long as protrusions of the magnetic plates 91 and 91A are fixed to the supports 4 and 5.
[0086] In the above-described examples, closing

operation is performed by the electromagnetic operation mechanisms 60 and 60A. However, the electromagnetic operation mechanisms 60 and 60A can be configured to perform at least one of tripping operation and the maintenance of the tripped state in addition to closing operation. In this case, in addition to the electromagnetic coil 62 for closing operation, additional electromagnetic coils for moving the drive shaft 65 downward are fixed to the fixed iron cores 61 and 61A, and at least one of tripping operation and the maintenance of the tripped state is performed by supplying an excitation current to the additional electromagnetic coils. [0087] The configurations described in the above-mentioned embodiments indicate examples of the contents of the present invention. The configurations can be combined with another well-known technique, and some of the configurations can be omitted or changed in a range not departing from the gist of the present invention.
Reference Signs List
[0088] 1 housing; 2 wall; 3 partition wall; 4, 5 support; 7 first space; 8 second space; 10 first fixed conductor; 10a fixed contact; 11 second fixed conductor; 12 electromagnetic coil; 20 mover; 20a movable contact; 30 flexible conductor; 41 contact-pressure spring; 42, 53 link pin; 50 transmission unit; 51 operation arm; 52 coupling plate; 54 shaft; 55 shaft center; 60, 60A electromagnetic operation mechanism; 61, 61A fixed iron core; 62 electromagnetic coil; 63 bobbin; 64 movable iron core; 65 drive shaft; 66, 7 6 guide member; 67, 95, 95a, 95b, 95c, 95d, 95e, 95f, 98, 98a, 98b, 98c, 98d, 98e, 98f, 98g coupling hole; 68 inner space; 69 guide hole; 7 0 coupling unit; 71, 72 coupling pin; 7 3 coupling link;

81, 81A first divided iron core; 82, 82A second divided iron core; 83, 83A first coupling member; 84, 84A second coupling member; 85, 85A third coupling member; 86, 86A fourth coupling member; 87, 87a, 87b, 87c, 87d, 87e, 87f coupling bolt; 88a, 88b, 88c, 88d, 88e, 88f nut; 90, 90A, 91, 91A magnetic plate; 92, 92A extension; 93, 93A first protrusion; 94, 94A second protrusion; 9 6, 97 mounting screw; 100 circuit breaker.

We Claim :
1. An electromagnetic operation mechanism comprising:
a fixed iron core;
a movable iron core provided movably with respect to the fixed iron core;
the electromagnetic operation mechanism includes:
an electromagnetic coil fixed to the fixed iron core, the electromagnetic coil being configured to generate a magnetic flux to move the movable iron core; and
a drive shaft coupled to the movable iron core,
the fixed iron core includes:
a first divided iron core and a second divided iron core each including a plurality of first magnetic plates stacked, the first divided iron core and the second divided iron core facing each other in a direction orthogonal to a stacking direction of the plurality of first magnetic plates; and
a plurality of coupling members to couple the first divided iron core and the second divided iron core,
each of the plurality of coupling members includes a second magnetic plate having a same shape as the first magnetic plates, the second magnetic plate being configured to couple the first divided iron core and the second divided iron core in an orientation different from an orientation of the first magnetic plates, and
the second magnetic plate constituting at least one of the plurality of coupling members includes
a fixing region to protrude outward from at least one of the first divided iron core and the second divided iron core in a direction orthogonal to the stacking direction, the fixing region being configured to be fixed to a support provided in a housing of a circuit breaker.

2. The electromagnetic operation mechanism according to
claim 1, wherein
a surface of the fixing region in the stacking direction is fixed to the support as a mounting surface for the support.
3. The electromagnetic operation mechanism according to
claim 1 or 2, wherein
a moving direction of the movable iron core is a direction orthogonal to the stacking direction, and
the fixing region of the second magnetic plate protrudes outward from at least one of the first divided iron core and the second divided iron core in a direction orthogonal to both the stacking direction and the moving direction of the movable iron core.
4. The electromagnetic operation mechanism according to
claim 1 or 2, wherein
the fixing region of the second magnetic plate protrudes outward from at least one of the first divided iron core and the second divided iron core in the moving direction of the movable iron core.
5. The electromagnetic operation mechanism according to
any one of claims 1 to 4, wherein
the first magnetic plates and the second magnetic plate each include a plurality of coupling holes, and
at least one of the plurality of coupling holes is formed in the fixing region.
6. The electromagnetic operation mechanism according to
claim 5, wherein
at least one of the plurality of coupling holes is

selectively used for coupling the second magnetic plate to the first magnetic plates of the first divided iron core and the second divided iron core and for fixing the second magnetic plate to the support.
7. A circuit breaker comprising:
a fixed conductor including a fixed contact; a mover including a movable contact; an electromagnetic operation mechanism including a shaft, to linearly move the shaft;
a transmission unit to move the mover depending on movement of the shaft to bring into contact with each other, and separate from each other, the fixed contact and the movable contact; and
a housing to cover the electromagnetic operation mechanism and the transmission unit, wherein
the electromagnetic operation mechanism includes a fixed iron core,
a movable iron core arranged movable relative to the fixed iron core,
an electromagnetic coil fixed to the fixed iron core to generate magnetic flux to move the movable iron core, and
a drive shaft joined to the movable iron core, the fixed iron core includes
a first divided iron core and a second divided iron core each formed of a stack of plurality of first magnetic plates, and facing each other in a direction perpendicular to a stacking direction of the plurality of first magnetic plates, and
a plurality of coupling members to join together the first divided iron core and the second divided iron

core,
the plurality of coupling members each include a second magnetic plate having a same shape as the first magnetic plates to join together the first divided iron core and the second divided iron core in a direction different from a direction of the first magnetic plates, and
the second magnetic plate included in at least one of the plurality of coupling members projects outward beyond at least one of the first divided iron core or the second divided iron core in a direction perpendicular to the stacking direction, and has a fixing region to be fixed to a support arranged on the housing of the circuit breaker.