JP6074720B2 - Electromagnetic trip device and circuit breaker - Google Patents

Description

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

  When the circuit breaker reaches a predetermined circuit state in a circuit in which a power source and a load are connected, the circuit breaker disconnects between the contacts to interrupt the circuit (see, for example, Patent Document 1). Examples of the circuit breaker include a circuit breaker, a leakage breaker, an overvoltage breaker, an undervoltage breaker, and the like. The circuit breaker interrupts the circuit when an abnormal current flows due to a short circuit or overload. The earth leakage breaker breaks the circuit when an earth leakage occurs. The overvoltage circuit breaker breaks the circuit when the voltage of the circuit is higher than a predetermined voltage. The undervoltage circuit breaker breaks the circuit when the voltage of the circuit is lower than a predetermined voltage. A composite circuit breaker combining the above circuit breakers may be used.

The circuit breaker includes a breaking mechanism that opens and closes the contacts, a handle that opens and closes the circuit, and an electromagnetic trip device that trips the contacts through the breaking mechanism.
In the electromagnetic tripping device provided in the circuit breaker described in Patent Document 1, the interlocking rod protrudes from the side surface of the housing, and the interlocking rod is inserted into the housing of the connected circuit breaker. When the abnormality occurs, the interlocking rod is moved to trip the circuit breaker breaking mechanism. In the electromagnet device, a coil wound around a bobbin, a first iron core passed through a hole in the bobbin, a second iron core attracted to the magnetic pole of the first iron core when energized to the coil, and a second iron core are adsorbed. And a coil spring that applies a load in a direction opposite to the direction in which the load is applied.

JP 2000-231869 A

  By the way, in the electromagnetic tripping device as described above, the first iron core is magnetized by supplying power to the coil to attract the second iron core, and the first iron core and the second iron core are brought into contact with each other. However, there is a possibility that the second iron core cannot be reliably brought into contact with the urging force of the coil spring only by the magnetic force of the first iron core.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an electromagnetic trip device and a circuit breaker capable of bringing the first iron core and the second iron core into contact with each other more reliably. There is to do.

  In order to solve the above problems, an electromagnetic trip device is provided with a coil spring, a first iron core that is inserted inside the coil spring, and spaced apart from the first iron core via the coil spring. An electromagnetic trip device in which the first iron core and the second iron core are brought into contact with and separated from each other by an electromagnetic force acting on the first iron core, one end of which is pivotally supported by a predetermined fulcrum. The other end side receives a pressing force from the movable link, and is configured to be rotatable about the fulcrum, and an iron core holder portion that rotates in the direction in which the first iron core and the second iron core are brought close to each other by the electromagnetic force; An urging means for urging the second iron core toward the first iron core is provided between the iron core holder portion and the second iron core.

In the above configuration, it is preferable that the urging means is a leaf spring having an arcuate cross section in which both end portions are locked to the iron core holder portion and the center portion is curved toward the second iron core side.
Moreover, the said structure WHEREIN: It is preferable that the said iron core holder part has an iron core position control part which controls the position shift of a said 2nd core against the urging | biasing force of the urging means with respect to the said 2nd iron core.

  Moreover, in order to solve the said subject, the circuit breaker was provided with the electromagnetic trip apparatus of one of the said structures.

  According to the electromagnetic trip device and the circuit breaker of the present invention, the first iron core and the second iron core can be brought into contact with each other more reliably.

The disassembled perspective view which shows the structure of a circuit breaker. The left view which shows the structure of the circuit breaker in an OFF state. The right view which shows the structure of the circuit breaker in an OFF state. The perspective view which shows the structure of an electromagnetic trip apparatus. The disassembled perspective view which shows the structure of an electromagnetic trip apparatus. The side view which shows the structure of an electromagnetic trip apparatus. Sectional drawing which shows the structure of an electromagnetic trip apparatus. Sectional drawing which shows the structure of an electromagnetic trip apparatus. 9-9 sectional drawing of FIG. 6 which shows the structure of an electromagnetic trip apparatus. The left view which shows the structure of the circuit breaker in an ON state. The left view which shows the structure of the circuit breaker in the moment when an undervoltage trip. The left view which shows the structure of the circuit breaker in an undervoltage trip state. Explanatory drawing for demonstrating the contact state of a movable link and an iron core holder part. The left view for demonstrating a holder part. Sectional drawing for demonstrating a holder part.

  Hereinafter, an embodiment in which the electromagnetic trip device is embodied as an undervoltage circuit breaker which is a kind of circuit breaker will be described. The undervoltage circuit breaker interrupts the circuit when the voltage of the circuit becomes lower than a predetermined voltage. The undervoltage circuit breaker is used in combination with a circuit breaker such as a circuit breaker that breaks the circuit when an abnormal current due to a short circuit or overload flows.

  As shown in FIG. 1, the casing 10 of the undervoltage circuit breaker includes a bottomed cylindrical first cover 11 and a bottomed cylindrical second cover 12. The first cover 11 and the second cover 12 are made of, for example, an insulating synthetic resin. The housing 10 is assembled into a substantially flat box shape by being assembled with the opening 11a of the bottomed cylindrical first cover 11 and the opening 12a of the bottomed cylindrical second cover 12 facing each other. ing.

  As shown in FIGS. 2 and 3, the first cover 11 and the second cover 12 are long in one side (left and right direction in FIGS. 2 and 3) and in the other side (in FIGS. 3 in the vertical direction). Here, the assembly direction is the width direction X, the longitudinal direction of the first and second covers 11 and 12 is the longitudinal direction Y, and the lateral direction of the first and second covers 11 and 12 is the lateral direction Z. The short direction Z is a direction orthogonal to the width direction X and the longitudinal direction Y.

  As shown in FIGS. 1 to 3, a terminal portion 13 for connecting an external electric wire is provided in the casing 10 of the undervoltage circuit breaker. The terminal portion 13 is provided at a position shifted from the center of the housing 10 (left side in FIG. 2) so that an external electric wire can be easily connected from the outside of the housing 10.

  In the space formed by the first cover 11 and the second cover 12, a handle 20, a display member 30, a blocking mechanism 40, an electromagnetic trip device 90, and a circuit board 14 on which an excitation circuit is mounted are arranged. ing. A handle gate 16 is formed at the center of the upper surface of the casing 10 of the undervoltage circuit breaker. A display window 17 is formed on the side of the upper surface of the casing 10 of the undervoltage circuit breaker opposite to the terminal portion 13.

  As shown in FIGS. 2 and 3, the blocking mechanism 40 includes an interlocking piece 41, a movable link 50, a thrust bar 60, and a latch member 70. A display member 30 and a display latch member 80 are housed inside the housing 10 in order to display the operating state of the undervoltage circuit breaker.

  As shown in FIGS. 1 to 3, the handle 20 includes a columnar rotation unit 21 and an operation unit 22. The rotation unit 21 rotates about a first rotation shaft 18 provided in the first cover 11. The handle 20 rotates about the first rotation shaft 18 when the operation unit 22 is operated.

  As shown in FIG. 1, the operation portion 22 is provided with a square rod-like connecting rod 23 that is connected to the operation portion of the handle of the circuit breaker to be connected. Thereby, the handle 20 of the undervoltage circuit breaker can be rotated together with the handles of other circuit breakers by the connecting rod 23. Here, the time when the operation unit 22 is located on the side opposite to the terminal unit 13 is the on position (energization position), and the time when the operation unit 22 is located on the terminal unit 13 side is the off position (current interruption position). The handle 20 is constantly applied with an urging force in a direction rotating from the on position to the off position by the handle spring 25. The rotation direction of the handle 20 from the off position to the on position is referred to as “on rotation direction”, and the rotation direction of the handle 20 from the off position to the on position is referred to as “off rotation direction”.

  As shown in FIGS. 1 to 3, the interlocking piece 41 is supported so as to be rotatable about a third rotation shaft 43. The interlocking piece 41 holds one end of a metal interlocking rod 42. The other end of the interlocking rod 42 protrudes from the slit 12b of the second cover 12 and is connected to an interlocking piece of another circuit breaker.

  The movable link 50, the latch member 70, and the display member 30 rotate about the second rotation shaft 19. Both ends of the second rotation shaft 19 are held by the housing 10. The movable link 50 is constantly applied with an urging force in the off-rotation direction of the handle 20 by a return spring 55 made of a coil spring and a return spring 56 made of a torsion coil spring.

  One ends of the return springs 55 and 56 are respectively engaged with the first cover 11. The other ends of the return springs 55 and 56 are locked to the movable link 50. An urging force in the off-rotation direction is constantly applied to the handle 20 by the handle spring 25.

In addition, the display latch member 80 is constantly given a biasing force in the on-rotation direction of the handle 20 by a display latch spring 83 that is a torsion coil spring.
The thrust bar 60 is formed in a U shape by a metal round bar. The operation side end 61 of the thrust bar 60 is inserted into the connection hole 24 of the handle 20. The transmission side end 62 of the thrust bar 60 is disposed in a link hole 54 formed by the engaging protrusion 51 of the movable link 50 and the latch piece 71 of the latch member 70. This state is a state where the thrust bar 60 is latched by the latch member 70 (latched state). In this latched state, the movement of the handle 20 is transmitted to the movable link 50 via the thrust bar 60.

  On the other hand, when the movable link 50 is driven by the electromagnetic trip device 90 and the movable link 50 and the latch member 70 are relatively rotated, the link hole 54 is opened. Then, the transmission side end 62 of the thrust bar 60 comes out of the link hole 54, and the thrust bar 60 is unlatched (latched state).

  The display latch member 80 is supported so as to be rotatable about the fourth rotation shaft 82. The display latch member 80 is constantly applied with an urging force in the off-rotation direction of the handle 20 by the display latch spring 83. The upper end portion 81 of the display latch member 80 comes into contact with the engaging convex portion 32 provided on the lower side of the display member 30 from the lower side, so that the display member 30 cannot be rotated in the off rotation direction of the handle 20. ing. The tip of the display member 30 is a display unit 31 that displays a circuit state. The upper surface of the display unit 31 is divided into two regions along the direction of the display member 30. On the upper surface of the display member 30, a normal region 31a indicating a normal state and a trip region 31b indicating a trip state are arranged in order from the handle 20 side. One of these areas 31a and 31b is exposed from the display window 17.

  A circuit board 14 is accommodated in the housing 10. The circuit board 14 includes an electromagnetic trip device 90 that drives the latch member 70 in response to energization of the coil 92, and an excitation circuit that stops the excitation of the coil 92 of the electromagnetic trip device 90 when an abnormality in the power supply voltage is detected. The component is mounted.

  As shown in FIGS. 4 and 5, the electromagnetic trip device 90 includes a bobbin 91, a coil 92, a fixed iron core 93, a spacer 110, a holder portion 96, a movable iron core 97, and a coil spring 98. ing. The fixed iron core 93 corresponds to the first iron core, and the movable iron core 97 corresponds to the second iron core.

  The fixed iron core 93 is a magnetic material (for example, iron) and is formed in a U shape by a plate material. The lower leg piece 95 of the fixed iron core 93 is inserted into the hole of the bobbin 91. At both ends of the bobbin 91, an insertion side flange 91a and a protruding side flange 91b are provided. The tip of the lower leg piece 95 of the fixed iron core 93 is exposed from the protruding side flange portion 91 b of the bobbin 91. A coil spring 98 is provided around the upper leg piece 94 of the fixed iron core 93.

  As shown in FIGS. 14 and 15, the resin holder 96 is provided at the end of the housing 96a with a bottomed tubular housing 96a that houses a plate-shaped movable iron core 97 made of a magnetic material. Holder rotating shaft 96b.

  The bottom portion 101 of the accommodating portion 96a has a long rectangular plate shape on one side. The accommodating portion 96a has first to fourth side walls 102 to 105 extending from the four side edges of the bottom portion 101 in a direction orthogonal to the surface direction of the bottom portion 101, and is configured to have a substantially bottomed cylindrical shape. The The first side wall 102 and the second side wall 103 are substantially parallel wall surfaces. The third side wall 104 and the fourth side wall 105 are substantially parallel wall surfaces, and are wall surfaces that are substantially orthogonal to the first side wall 102 and the second side wall 103.

  The accommodating portion 96a includes two closing plates 107 and 108 that close a part of the opening. One blocking plate 107 is formed so as to extend from both the first side wall 102 and the third side wall 104 of the housing portion 96a in a direction substantially orthogonal to the side walls 102 and 104. The other closing plate 108 is formed so as to extend from both the second side wall 103 and the third side wall 104 of the housing portion 96a in a direction substantially orthogonal to the side walls 103, 104. One closing plate 107 and the other closing plate 108 are formed so as to be separated from the fourth side wall 105. Further, the one closing plate 107 and the other closing plate 108 are formed in a manner of being separated from each other.

  The holder rotation shaft 96 b is formed to extend from the first side wall 102 and the second side wall 103 in a direction substantially orthogonal to the surface direction of the first side wall 102 and the second side wall 103. The holder rotation shaft 96b is rotatably supported by the protruding side flange 91b. For this reason, the holder part 96 can be rotated around the holder rotating shaft 96b. Thereby, the movable iron core 97 accommodated in the holder part 96 (accommodating part 96a) is brought into contact with the front end surfaces (magnetic pole surfaces) of both leg pieces 94, 95 of the fixed iron core 93, and both leg pieces 94 of the fixed iron core 93, It can be rotated between a position away from the tip face (magnetic pole face) of 95.

  As shown in FIGS. 6-8, the holder part 96 is equipped with the processus | protrusion 96c on the opposite side to the said holder rotating shaft 96b side. The protrusion 96c contacts the engaging protrusion 53 of the movable link 50 when the holder portion 96 is rotated, and rotates the movable link 50 in the on-rotation direction.

  As shown in FIG. 15, the urging portion B is interposed in the holder portion 96 between the movable iron core 97 housed in the housing portion 96 a and the bottom portion 101. As shown in FIG. 15, the urging portion B is a leaf spring having a substantially circular cross section. The urging portion B has both end portions in contact with the bottom portion 101 and a central portion thereof bent to the movable iron core 97 side. For this reason, the movable iron core 97 is urged toward the fixed iron core 93 by the urging portion B.

  The movable iron core 97 is urged toward the fixed iron core 93 by the urging portion B in the housing portion 96a. At this time, the movement of the movable iron core 97 is restricted by the closing plates 107 and 108. For this reason, it is suppressed that the movable iron core 97 falls out of the accommodating part 96a.

  As shown in FIGS. 8 and 9, the fixed iron core 93 is attached with a spacer 110 that suppresses the space between the outer circumference of the fixed iron core 93 and the inner circumference of the coil spring 98. The spacer 110 includes two plate pieces 111 and 112 that extend in the extending direction of the upper leg piece 94 of the fixed iron core 93 and face each other, and a connection piece 113 that connects the plate pieces 111 and 112. The spacer 110 is positioned in the front-rear direction by the connection piece 113 coming into contact with the back surface 93 a of the fixed iron core 93. The spacer 110 is positioned in the vertical direction by the lower part of the plate pieces 111, 112 on the connection piece 113 side coming into contact with the insertion side flange 91 a of the bobbin 91. The outer shape of the spacer 110 is set so as not to generate a frictional force that hinders the expansion and contraction of the coil spring 98. The spacer 110 is located in the space between the outer periphery of the fixed iron core 93 and the inner periphery of the coil spring 98, thereby suppressing the coil spring 98 from being deformed inside the coil spring 98. For this reason, the coil spring 98 is not greatly deformed, and the load obtained from the coil spring 98 is stabilized. Further, the magnetic field is stabilized by stabilizing the coil spring load.

The operation of the undervoltage circuit breaker will be described with reference to FIGS.
First, an operation when the handle 20 is moved from the off position to the on position and the undervoltage circuit breaker is switched from the off state shown in FIG. 2 to the on state shown in FIG. 10 will be described.

  As shown in FIG. 10, when the handle 20 is rotated from the off position toward the on position (on rotation direction), the engagement protrusion 51 of the movable link 50 is pushed by the thrust bar 60, and the movable link 50 is turned on. Rotate in the direction of rotation.

  Here, a straight line connecting the first rotation shaft 18 of the handle 20 and the transmission side end 62 of the thrust bar 60 is defined as a switching boundary line L. When the handle 20 is rotated and the operation side end 61 of the thrust bar 60 exceeds the switching boundary line L, the transmission side end 62 of the thrust bar 60 is stopped while being pressed against the engagement protrusion 51. At this time, the handle 20 and the thrust bar 60 are held in the on position, and the undervoltage circuit breaker is turned on.

  The latch member 70 receives the urging force of the latch spring 34 and rotates to a position where it comes into contact with the transmission side end 62 side of the thrust bar 60. When the locking portion 33 of the display member 30 is pushed by the movable link 50, the display member 30 rotates in the on rotation direction and moves to the display reset position. In this state, the display latch member 80 receives an urging force and moves to a position where the display member 30 can be latched. The interlocking piece 41 rotates in the on-rotation direction in accordance with the rotation of the movable link 50 and displaces the interlocking piece of another circuit breaker via the interlocking rod 42. Further, when the power supply voltage is normal in the ON state, the electromagnetic trip device 90 is energized to the coil 92 by the excitation circuit, and the movable iron core 97 is attracted to the fixed iron core 93. The holder portion 96 is in a state of rotating to the on position against the urging force of the coil spring 98. In this state, the protrusion 96 c at the tip of the holder portion 96 has moved to a position away from the movable link 50.

Next, the operation when the handle 20 is moved from the on position to the off position and the undervoltage circuit breaker is switched from the on state shown in FIG. 10 to the off state shown in FIG. 2 will be described.
As shown in FIG. 2, when the handle 20 is rotated in the off rotation direction from the on position to the off position, the latch member 70 is pulled by the thrust bar 60. The latch member 70 rotates in the off-rotation direction of the handle 20 against the urging force of the latch spring 34, and the link hole 54 is opened upward.

  The movable link 50 receives the urging force of the return springs 55, 56 and rotates in the off-rotation direction of the handle 20, and is fixed to the engagement hole 11 b of the first cover 11 and the engagement hole 12 c of the second cover 12. Stops in contact with the rod-shaped fixing pin 99. The engagement hole 11b of the first cover 11 and the engagement hole 12c of the second cover 12 are formed in the vicinity of the protrusion 96c that is the end of the holder portion 96 opposite to the holder rotation shaft 96b. For this reason, the contact tip portion 57 that contacts the fixed pin 99 of the movable link 50 and the engagement protrusion 53 of the movable link 50 are brought close to each other, and the enlargement of the movable link 50 can be suppressed. Yes. Here, as shown in FIGS. 1 to 3, the fixing pin 99 is made of a metal material having higher rigidity than the iron core holder portion 96. For this reason, even if the movable link 50 receiving the urging force of the return springs 55 and 56 contacts the fixed pin 99, the metal fixed pin 99 having higher rigidity than the resin iron core holder portion 96 has a chipping or Occurrence of aging deterioration is suppressed.

  Then, the interlocking piece 41 rotates in the off-rotation direction of the handle 20 against the urging force by being pushed by the protrusion 72 of the latch member 70. The display member 30 receives the urging force of the latch spring 34 and rotates in the off-rotation direction of the handle 20, and the engagement convex portion 32 comes into contact with the upper end portion 81 of the display latch member 80 and stops. In this state, the normal area 31 a of the display unit 31 is exposed from the display window 17.

The protrusion 96 c at the tip of the holder portion 96 is pushed by the engagement protrusion 53 when the movable link 50 rotates in the off-rotation direction of the handle 20.
As a result, the holder portion 96 rotates in the off-rotation direction of the handle 20 so as to change from the state of FIG. 10 to the state of FIG. At this time, as described above, the movable link 50 abuts on the fixed pin 99, and the movement of the handle 20 in the off-rotation direction is restricted. For this reason, even if the holder portion 96 is rotated in the on-rotation direction (clockwise direction in FIG. 2) of the handle 20 about the holder rotation shaft 96b by the coil spring 98, the engagement protrusion 53 of the movable link 50 causes the holder The rotation of the part 96 is restricted.

  At this time, as shown in FIG. 13, the holder portion 96 and the movable link 50 include a side surface S <b> 1 positioned on the on-rotation direction side of the projection 96 c of the holder portion 96, and a distal end surface S <b> 2 of the engagement projection 53 of the movable link 50. Are in contact with each other substantially in parallel. Furthermore, each surface S1, S2 is orthogonal to the urging force of the coil spring 98 that rotates the holder portion 96 in the on-rotation direction of the handle 20. In FIG. 13, the angle θ formed by the surface RS parallel to the urging force of the coil spring and the side surface S1 is shown to be 90 degrees.

  The holder 96 is urged by the coil spring 98 in a state where the holder 96 is in contact with the engaging protrusion 53, whereby the position of the holder 96 is fixed and the movable core 97 is in contact with the magnetic pole surface of the fixed core 93. Is held in. At this time, since the movable iron core 97 is urged toward the fixed iron core 93 by the urging portion B, the movable iron core 97 is reliably brought into contact (contact) with the magnetic pole surface of the fixed iron core 93.

  Next, when the undervoltage breaker switches from the ON state shown in FIG. 10 to the trip state shown in FIG. 12 through the moment when the undervoltage trip occurs in FIG. The operation will be described.

  In the ON state shown in FIG. 10, when the excitation circuit detects that the power supply voltage is below a predetermined set value lower than the rated voltage (undervoltage condition), the excitation circuit trips the undervoltage circuit breaker. The switch connected in series to the coil 92 is turned off.

  At this time, as shown in FIG. 11, the energization to the coil 92 is stopped, and the electromagnetic attractive force generated between the fixed iron core 93 and the movable iron core 97 is eliminated, so that the holder portion 96 receives the urging force of the coil spring 98. Thus, the handle 20 rotates in the on-rotation direction. When the holder portion 96 rotates in the on-rotation direction of the handle 20, the contact surface 96 e of the holder portion 96 contacts the latch member 70, and the latch member 70 is rotated in the off-rotation direction of the handle 20, thereby transmitting the thrust bar 60 on the transmission side. The end 62 is separated from the latch piece 71 of the latch member 70. When the latch piece 71 of the latch member 70 is separated from the transmission side end 62 of the thrust bar 60, the handle 20 rotates in the off-rotation direction around the operation side end 61.

  As shown in FIG. 12, the transmission side end 62 of the thrust bar 60 is disengaged outside the link hole 54, so that the movable link 50 that has lost the support of the thrust bar 60 receives the urging force of the return springs 55 and 56. The handle 20 rotates in the off rotation direction and moves to the off position. Further, the interlocking piece 41 is pushed upward by the protrusion 72 of the latch member 70, the opening / closing mechanism of another circuit breaker is driven by the interlocking rod 42, and the contact is turned off by the opening / closing mechanism. Thereby, the power supply to the load device connected to another circuit breaker is interrupted, and the load device can be protected. The holder portion 96 receives the urging force of the coil spring 98 and rotates in the on-rotation direction of the handle 20. However, when the projection 96 c comes into contact with the engagement projection 53 of the movable link 50, the urging force of the return springs 55 and 56 is obtained. Is set to be larger than the urging force of the coil spring 98, the handle 20 cannot be further rotated in the on-rotation direction.

  When the movable link 50 receives the urging force of the return springs 55 and 56 and rotates in the off-rotation direction of the handle 20, the projection 96 c of the holder portion 96 is pushed by the engagement projection 53 of the movable link 50. Then, the holder part 96 rotates in the off-rotation direction of the handle 20 so as to change from the state of FIG. 11 to the state of FIG. At this time, as described above, the movable link 50 abuts on the fixed pin 99, and the movement of the handle 20 in the off-rotation direction is restricted. For this reason, even if the holder portion 96 is rotated in the on-rotation direction (clockwise direction in FIG. 12) of the handle 20 around the holder rotation shaft 96b by the coil spring 98, the engagement protrusion 53 of the movable link 50 causes the holder The rotation of the part 96 is restricted.

  At this time, as shown in FIG. 13, the holder portion 96 and the movable link 50 include a side surface S <b> 1 positioned on the on-rotation direction side of the projection 96 c of the holder portion 96, and a distal end surface S <b> 2 of the engagement projection 53 of the movable link 50. Are in contact with each other substantially in parallel. Furthermore, each surface S1, S2 is orthogonal to the urging force of the coil spring 98 that rotates the holder portion 96 in the on-rotation direction of the handle 20.

  The holder 96 is urged by the coil spring 98 in a state where the holder 96 is in contact with the engaging protrusion 53, whereby the position of the holder 96 is fixed and the movable core 97 is in contact with the magnetic pole surface of the fixed core 93. Is held in. At this time, since the movable iron core 97 is urged toward the fixed iron core 93 by the urging portion B, the movable iron core 97 is reliably brought into contact (contact) with the magnetic pole surface of the fixed iron core 93.

  Further, when the display latch member 80 is pushed by the protrusion 96d (see FIG. 3) of the holder portion 96 and rotates in the off-rotation direction of the handle 20, the latch of the display member 30 is released. When the latch is released, the display member 30 receives the biasing force of the latch spring 34 and rotates in the off-rotation direction of the handle 20. A trip area 31 b of the display unit 31 is exposed from the display window 17. After that, when the handle 20 receives the urging force of the handle spring 25 and rotates in the off-rotation direction of the handle 20 and moves to the off position, the transmission side end 62 of the thrust bar 60 passes through the opening of the link hole 54 and links. It is inserted into the hole 54 and moved to a position where it engages with the latch piece 71. At this time, the transmission side end 62 of the thrust bar 60 is inserted into the link hole 54 surrounded by the movable link 50 and the latch member 70, and the handle 20 is rotated in the on-rotation direction to move to the on position. Then, the state shown in FIG. 10 is obtained.

Next, the effect of this embodiment will be described.
(1) Since the movable iron core 97 is biased toward the fixed iron core 93, the movable iron core 97 and the fixed iron core 93 can be brought into contact with each other more reliably.

  (2) Since the urging portion B that urges the movable iron core 97 toward the fixed iron core 93 is a plate spring having an arcuate cross section, it is easily interposed between the movable iron core 97 and the accommodating portion 96a of the holder portion 93. It becomes possible.

(3) The holder portion 96 can restrict the displacement of the movable iron core 97 against the urging force of the urging portion B against the movable iron core 97 by the closing plates 107 and 108.
(4) Compared with the case where the movable iron core 97 is urged by cutting out a part of the holder portion 96, the urging portion B is made of a metal material having rigidity higher than that of the resin holder portion 96. Therefore, the urging force can be maintained for a longer time. As a result, the movable iron core 97 and the fixed iron core 93 can be brought into contact with each other longer and reliably.

In addition, you may change the said embodiment as follows.
In the above embodiment, the two closing plates 107 and 108 are provided, but the number and position thereof may be changed as appropriate.

  -In the said embodiment, although the undervoltage circuit breaker was employ | adopted as a circuit breaker, it is not restricted to this. For example, a circuit breaker having an electromagnetic trip device 90 may be applied to other circuit breakers such as an overvoltage circuit breaker.

Next, a technical idea that can be grasped from the above embodiment and another example will be added below.
(A) In the circuit breaker according to claim 4,
A handle that is rotatably supported between an on position that closes the movable contact with respect to the fixed contact and an off position that opens the movable contact with respect to the fixed contact;
A blocking mechanism that is directly or indirectly connected to the handle and that contacts and separates the movable contact with respect to the fixed contact in accordance with the rotation of the handle;
When the connected circuit reaches a predetermined circuit state, the electromagnetic trip device trips between the contacts to interrupt the circuit.

  Even if it is such a structure, the circuit breaker which can have the same effect as Claims 1-3 can be provided.

  DESCRIPTION OF SYMBOLS 10 ... Housing | casing, 11 ... 1st cover, 11a ... Opening part, 12 ... 2nd cover, 12a ... Opening part, 13 ... Terminal part, 20 ... Handle, 40 ... Shut-off mechanism, 41 ... Interlocking piece, 42 ... Interlocking rod , 43... 3rd rotation shaft, 50... Driving member, 51... Engaging protrusion, 52... Projection, 53. Bar 61, operation side end, 62 ... transmission side end, 70 ... latch member, 71 ... latch piece, 80 ... display latch member, 81 ... upper end, 82 ... fourth rotating shaft, 83 ... display latch spring , 90 ... Electromagnetic trip device, 91 ... Bobbin, 91a ... Insertion side collar, 91b ... Projection side collar, 92 ... Coil, 93 ... Fixed iron core (first iron core), 93a ... Back, 94 ... Upper leg piece, 95 ... Lower leg piece, 96 ... Holder part (iron core holder part), 96a ... Housing part, 96b ... Rudder rotation shaft (fulcrum), 96c ... protrusion, 96d ... protrusion, 97 ... movable iron core (second iron core), 98 ... coil spring, 99 ... fixing pin (regulator), 106 ... opening, 107,108 ... blocking Plate (iron core position restricting portion), B ... biasing portion (biasing means).

Claims (4)

A coil spring;
A first iron core inserted inside the coil spring;
A second iron core provided apart from the first iron core via the coil spring;
An electromagnetic trip device in which the first iron core and the second iron core are contacted and separated by electromagnetic force acting on the first iron core,
One end side is pivotally supported by a predetermined fulcrum, receives a pressing force from the other end, and is configured to be rotatable about the fulcrum. The second iron core is supported, and the first iron core is supported by the electromagnetic force. And an iron core holder that rotates in the direction in which the second iron core approaches
An electromagnetic trip device comprising urging means for urging the second iron core toward the first iron core between the iron core holder portion and the second iron core. The electromagnetic tripping device according to claim 1,
The biasing means is a leaf spring having an arcuate cross section in which both end portions are locked to the iron core holder portion and the central portion is curved toward the second iron core side. The electromagnetic tripping device according to claim 1 or 2,
2. The electromagnetic trip device according to claim 1, wherein the iron core holder portion includes an iron core position restricting portion that restricts a displacement of the second iron core against an urging force of the urging means with respect to the second iron core.   A circuit breaker comprising the electromagnetic trip device according to any one of claims 1 to 3.