CN104241047A - Electromagnetic tripping device and breaker - Google Patents

Abstract

An electromagnetic trip device (90) includes a coil spring (98). The first magnetic core (93) is inserted through the coil spring (98). The second core (97) is urged away from the first core by a coil spring. The first and second cores are moved into contact with each other and moved away from each other by the urging force generated by the coil spring and the electromagnetic force generated by the first core. The pivoting magnetic core holder (96) is pushed by the thrust of the driver link (50), and when the first magnetic core generates electromagnetic force, the pivoting magnetic core holder (96) between the first magnetic core and the second magnetic core Pivot in directions approaching each other. When the core holder (96) touches or approaches the driver link (50) and the first core (93) contacts the second core (97), the limiting portion (99) resists the thrust limit of the driver link (50) Movement of the driver linkage (50).

Description

Magnetic trip units and circuit breakers

technical field

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

Background technique

A circuit breaker is used to interrupt a circuit by opening contacts when a circuit connecting a power source and a load is in a predetermined circuit state (for example, refer to Japanese Patent Laid-Open No. 2000-231869). For example, the circuit breaker may be a molded case circuit breaker, an earth leakage circuit breaker, an overvoltage circuit breaker, an undervoltage circuit breaker, or the like. The molded case circuit breaker interrupts the circuit when a fault current caused by a short circuit or overload is detected. When an electrical leakage is detected, the earth leakage circuit breaker interrupts the circuit. The overvoltage circuit breaker interrupts the circuit when the voltage of the circuit becomes higher than a predetermined upper voltage limit. The undervoltage circuit breaker interrupts the circuit when the voltage of the circuit becomes lower than a predetermined lower voltage limit. Multifunction circuit breakers combining different types of circuit breakers are also known.

A typical circuit breaker includes a switch mechanism that closes and opens contacts, a lever for manually closing and opening the contacts, and an electromagnetic trip device that opens the contacts with the switch mechanism.

The circuit breaker disclosed in the '869 includes an electromagnetic trip device. The connecting rod protrudes from the housing of the electromagnetic trip unit. The connecting rod is fitted into the housing of the circuit breaker connected to the electromagnetic trip unit. When a fault voltage is generated, the electromagnetic tripping device moves the connecting rod and trips the interrupting mechanism of the circuit breaker. The electromagnetic trip device includes an electromagnetic unit. The electromagnetic unit includes a solenoid coil wound around a bobbin, a first core extending through a hole in the bobbin, a second core attracted to a pole of the first core when current flows through the solenoid coil and pushing the second core away from the A helical spring for the poles of the first magnetic core.

When current is supplied to the electromagnetic coil, the first magnetic core magnetically attracts the second magnetic core such that the magnetic cores abut each other. The inventors have noticed that bending stress may lead to plastic deformation of electromagnetic trip device components and that such deformation may destabilize the voltage characteristics of the electromagnetic trip device.

Contents of the invention

The object of the present invention is to provide an electromagnetic trip device and a circuit breaker with stable voltage characteristics.

One aspect of the invention is an electromagnetic trip device that includes a coil spring. The first magnetic core is inserted through the coil spring. The second core is urged away from the first core by a helical spring. The first magnetic core and the second magnetic core are configured such that the first magnetic core and the second magnetic core are moved into contact with each other and moved away from each other by an urging force generated by a coil spring and an electromagnetic force generated by the first magnetic core. The pivoting core holder includes a base end and a distal end. The base end includes a pivot. The distal end is pushed by the thrust of the driver linkage. When the first core generates an electromagnetic force, the core holder pivots in a direction in which the first core and the second core approach each other. When the core holder is in contact with or close to the driver link and the first core is in contact with the second core, the restricting portion restricts movement of the driver link against a thrust force of the driver link.

An aspect of the present invention reduces plastic deformation of the core holder and reduces displacement of the driver link from the stop position, thus obtaining an electromagnetic trip device with stable voltage characteristics.

In a certain example, the restricting portion is disposed proximate to the distal end away from the core holder pivot.

In a certain example, the core holder is urged by a coil spring and pivots about a pivot in a direction in which the second core moves away from the first core. The core holder includes a contact surface that contacts the driver linkage. When the contact surface is in contact with the driver link, the contact surface extends perpendicular to the direction of the urging force of the coil spring.

In a certain example, contact of the limiting portion with the driver link limits a movable range of the driver link.

In one example, the driver link is supported to pivot about its base end. The driver link includes a distal end that contacts the restricting portion when the driver link pivots. The driver link includes an engaging protrusion between a base end and a distal end of the driver link, wherein the engaging protrusion contacts the distal end of the core holder. The restricting portion is a rigid element that contacts the distal end of the driver link when the engagement protrusion of the driver link contacts the distal end of the core holder.

Another aspect of the present invention provides a circuit breaker comprising an electromagnetic tripping device according to one or more of the above aspects and examples.

The circuit breaker may include a lever supported to pivot between an on position in which the movable contact contacts the fixed contact and an off position in which the the movable contact moves away from the fixed contact; and an interruption mechanism connected directly or indirectly to the lever, wherein when the lever pivots, the interruption mechanism moves the movable contact away from the fixed contact, Wherein the electromagnetic trip device is configured to move the movable contact away from the fixed contact when a predetermined circuit condition is detected.

According to one embodiment, the combined circuit breaker assembly comprises a first circuit breaker and a second circuit breaker connected to the first circuit breaker, the first circuit breaker being said circuit breaker according to another aspect.

In a certain example, each of the circuit breaker and the further circuit breaker includes a rod, and the rods of the circuit breaker and the further circuit breaker are connected via a connecting rod.

Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.

Description of drawings

The invention, together with its objects and advantages, can be best understood by reference to the following description of presently preferred embodiments and the accompanying drawings, in which:

Figure 1 is an exploded perspective view of a circuit breaker;

Fig. 2 is a left side view of the circuit breaker in the disconnected state;

Figure 3 is a right side view of the circuit breaker in the off state;

Fig. 4 is a perspective view of the electromagnetic tripping device;

Fig. 5 is an exploded perspective view of the electromagnetic tripping device;

Fig. 6 is a side view of the electromagnetic tripping device;

Fig. 7 is a cross-sectional view of the electromagnetic tripping device;

Fig. 8 is a cross-sectional view of the electromagnetic tripping device;

Figure 9 is a cross-sectional view of the electromagnetic trip device taken along line 9-9 of Figure 6;

Figure 10 is a left side view of the circuit breaker in the on state;

Fig. 11 is a left side view showing the circuit breaker when an undervoltage trip occurs;

12 is a left side view showing the circuit breaker in an undervoltage trip state;

Figure 13 is a schematic diagram showing the contact of the driver linkage with the core holder; and

14A and 14B show a combined circuit breaker assembly including the circuit breaker of FIG. 1 and an additional circuit breaker.

Detailed ways

One embodiment of an electromagnetic trip device and a circuit breaker including the electromagnetic trip device will now be described. The circuit breaker may be an undervoltage circuit breaker 1 which interrupts the circuit when the voltage of the circuit becomes lower than a predetermined lower voltage limit. Undervoltage circuit breakers may be used with different types of circuit breakers, such as molded case circuit breakers that interrupt a circuit when a fault current caused by a short circuit or overload is detected.

As shown in FIG. 1 , the undervoltage circuit breaker 1 may include a housing 10 including a first cover 11 and a second cover 12 . The first cover 11 and the second cover 12 may be formed of insulating synthetic resin. The open end 11a of the first cover 11 is combined with the open end 12a of the second cover 12 so as to define an internal compartment within the housing 10 .

Figure 1 includes an orthogonal coordinate system indicating the orientation of the undervoltage circuit breaker. The same orthogonal coordinate system is also included in the other drawings.

As shown in FIGS. 1 to 3, the undervoltage circuit breaker includes a terminal unit 13 connected to an external power source. The terminal unit 13 can be arranged in the housing 10 of the undervoltage circuit breaker.

The rod 20 , the indicator 30 , the interrupt mechanism 40 , the electromagnetic trip device 90 and the circuit board 14 are arranged within the inner compartment of the housing 10 . The circuit board 14 includes an excitation circuit. A lever door 16 and an indicator window 17 are formed in the upper surface of the housing 10 .

As shown in FIGS. 2 and 3 , the interruption mechanism 40 includes a fitting 41 , a driver link 50 (movable link), a thrust rod 60 and a locking member 70 . The housing 10 accommodates an indicator 30 and an indicator latch 80 within the indicator window 17 indicating the operating state of the undervoltage circuit breaker.

The lever 20 includes a pivot 21 and a lever protrusion 22 . The pivot 21 pivots about the first pivot 18 which may be connected to the first cover 11 or which may be formed on the first cover 11 . When the lever protrusion 22 is operated, the lever 20 pivots about the first pivot 18 .

A connecting rod 23 extends from the rod protrusion 22 parallel to the first pivot 18 . The connecting rod 23 may be connected to a rod 20A of another circuit breaker 1A to form a combined circuit breaker assembly 2, as shown in Figures 14A and 14B. The connecting rod 23 thus pivots the rod 20 of the undervoltage circuit breaker 1 together with the rod 20A of the other circuit breaker 1A. Further one or more circuit breakers may be connected to said circuit breaker 1 and/or said further circuit breaker 1A. In the illustrated example, when the lever protrusion 22 is moved away from the terminal unit 13, the lever protrusion 22 is in the on position (closed position) and when the lever protrusion 22 is moved close to the terminal unit 13, the lever protrusion 22 is in the ON position (closed position). Disconnected position (open position). The lever 20 is always pushed away from the on position, for example by a lever spring 25 . In the following description, the direction in which the lever 20 pivots from the off position shown in FIG. 2 to the on position shown in FIG. The direction in which the position pivots to the disconnected position (counterclockwise in FIG. 2 ) is called the disconnected direction.

The fitting 41 is pivotally supported by a third pivot 43 . The fitting 41 holds one end of a fitting rod 42 which may be a metal rod. The other end of the fitting rod 42 protrudes outside the second cover 12 through the slit 12b and is connected to a fitting of another circuit breaker.

The driver link 50 , the latch 70 and the indicator 30 pivot about the second pivot 19 . The second pivot 19 includes two ends supported by the housing 10 . The return spring 55 (which may be a coil spring) and the return spring 56 (which may be a torsion spring) push the driver link 50 in the opening direction all the time.

Both return springs 55 and 56 have one end connected to the first cover 11 and the other end connected to the driver link 50 . The lever spring 25 pushes the lever 20 all the way in the opening direction. The indicator lock spring 83 (which may be a torsion spring) always pushes the indicator lock 80 in the switch-on direction.

The thrust rod 60 may be a metal round rod bent into a U shape. The thrust rod 60 includes an operating end 61 and a transmitting end 62 . The operating end 61 is fitted into the connection hole 24 of the rod 20 . The transmission end portion 62 is arranged in the link hole 54 formed by the joint portion 51 of the driver link 50 and the lock portion 71 of the lock piece 70 . In this case, the thrust lever 60 is locked by the locking member 70 (locked state). In the latched state, the thrust rod 60 transmits the movement of the rod 20 to the driver link 50 .

When the driver link 50 is driven by the electromagnetic trip device 90 , the driver link 50 and the latch 70 pivot relative to each other and this causes the link hole 54 to open. Then, the transfer end 62 of the thrust rod 60 moves out of the link hole 54 . In this case, the thrust rod 60 is released from the lock member 70 (unlocked state).

The fourth pivot 82 pivotally supports the indicator latch 80 . The indicator lock spring 83 always pushes the indicator lock 80 in the opening direction. The indicator latch 80 includes an upper end 81 and the underside of the indicator 30 includes an engagement protrusion 32 . When the upper end portion 81 of the indicator latch 80 contacts the engagement protrusion 32 of the indicator 30 , further rotation of the indicator 30 in the disconnection direction is restricted. The indicator 30 includes a distal end defining an indicating portion 31 indicating the state of the circuit. The indication portion 31 includes an upper surface divided into two regions. A side of the indicating portion close to the lever 20 defines a normal area 31a, and a side of the indicating portion remote from the lever 20 defines a tripping area 31b. One of the regions 31 a and 31 b is exposed from the indicator window 17 .

The housing 10 accommodates a circuit board 14 . An electromagnetic trip device 90 is mounted on the circuit board 14 to actuate the latch 70 by supplying current to the electromagnetic coil 92 . The circuit board 14 includes an excitation circuit that stops excitation of the electromagnetic coil 92 of the electromagnetic trip device 90 when a fault voltage is detected.

Referring to FIGS. 4 and 5 , the electromagnetic trip device 90 includes a bobbin 91 formed of synthetic resin, an electromagnetic coil 92 , a fixed core 93 , a spacer 100 , a retainer 96 , a movable core 97 and a coil spring 98 . The fixed core 93 and the movable core 97 function as a first core and a second core, respectively.

The fixed magnetic core 93 may be formed of a magnetic material (iron) plate. In the illustrated embodiment, stationary magnetic core 93 is U-shaped and includes a first or upper arm 94 and a second or lower arm 95 . The lower arm 95 fits into the hole of the bobbin 91 . One end of the bobbin 91 includes an inlet flange 91a and the other end of the bobbin 91 includes an outlet flange 91b. The lower arm 95 of the stationary magnetic core 93 includes a distal end exposed from the exit flange 91 b of the bobbin 91 . The coil spring 98 is held on the upper arm 94 of the fixed magnetic core 93 .

Referring to FIGS. 6 to 8 , the retainer 96 is pivotally attached to the outlet flange 91 b of the bobbin 91 . The protrusion 96 b protrudes from the distal end of the holder 96 . When the retainer 96 pivots, the protrusion 96b pushes the engagement protrusion 53 of the driver link 50 and rotates the driver link 50 in the ON direction. In the illustrated embodiment, the engagement protrusion 53 is arranged at an intermediate position between the distal end and the proximal end portion of the driver link 50 . A movable magnetic core 97 , which may be a plate of magnetic material, is held by a holder 96 via a spring plate element B . The holder 96 includes a holder pivot 96 a pivotally supported by the outlet flange 91 b of the bobbin 91 . As the holder 96 pivots about the holder pivot 96a, the movable core 97 pivots between two positions in which the movable core 97 contacts the two arms 94 of the fixed core 93 The position of the distal end surfaces (pole surfaces) of and 95 and the position where the movable core is separated from the distal surfaces (pole surfaces) of the two arms 94 and 95 of the fixed core 93 .

Referring to FIGS. 8 and 9 , a spacer 100 is attached to the fixed core 93 so as to reduce the gap between the outer surface of the fixed core 93 and the inner contour of the coil spring 98 . The spacer 100 includes a plurality of elongated portions 101 and 102 extending in the axial direction of the coil spring 98 . In the example shown, the elongated portions 101 and 102 are two plates facing each other and extending along the upper arm 94 of the fixed magnetic core 93 . The bridging portion 103 connects the elongated portions 101 and 102 . The contact of the bridge portion 103 with the rear surface 93 a of the fixed core 93 positions the spacer 100 relative to the fixed core 93 in the axial direction. The shape and size of the spacer 100 are set so that no frictional force that hinders the extension and contraction of the coil spring 98 is generated. The arrangement of the spacer 100 within the gap between the outer surface of the stationary magnetic core 93 and the inner contour of the coil spring 98 prevents or limits twisting and bending of the coil spring 98 . This stabilizes the urging force of the coil spring 98 and stabilizes the performance or the magnetic field of the electromagnetic trip device.

The operation of the undervoltage circuit breaker will now be described with reference to FIGS. 2 and 3 and FIGS. 10 to 12 . First, the operation of the undervoltage circuit breaker when the undervoltage circuit breaker is switched from the OFF state of FIG. 2 to the ON state of FIG. 10 will be described.

When the lever 20 pivots from the off position ( FIG. 2 ) to the on position ( FIG. 10 ) in the on direction, the thrust rod 60 pushes the joint portion 51 of the driver link 50 and pivots the driver link 50 in the on direction. change.

The straight line between the first pivot 18 of the connecting rod 20 and the transfer end 62 of the thrust rod 60 is referred to as a switching boundary line. As the lever 20 pivots in the ON direction, when the operating end 61 of the thrust lever 60 crosses the switching boundary line, the transmission end 62 of the thrust lever 60 stops when pushed against the engagement portion 51 . Here, lever 20 and thrust lever 60 remain in the ON position, and the undervoltage circuit breaker becomes ON.

The latch 70 pivoted by the latch spring 34 pivots to a position where the latch 70 contacts the transfer end 62 of the thrust rod 60 . The driver link 50 pushes the engagement portion 33 of the indicator 30 . This causes the indicator 30 to pivot and move in the ON direction to indicate the reset position. In this case, the indicator lock spring 83 pushes and moves the indicator lock 80 to a position where the indicator lock 80 locks the indicator 30 . Also, the fitting 41 pivots in the ON direction as the driver link 50 pivots, and causes the fitting of another circuit breaker to move together with the fitting lever 42 . If the voltage is normal in the ON state, the excitation circuit supplies current to the electromagnetic coil 92 of the electromagnetic trip device 90 . This attracts the movable core 97 to the fixed core 93 . The retainer 96 pivots to the ON position against the urging force of the coil spring 98 . Here, the protrusion 96 b at the distal end of the retainer 96 is separated from the driver link 50 .

The operation of the undervoltage circuit breaker when the undervoltage circuit breaker is switched from the on state to the off state will now be described.

When the lever 20 pivots in the off direction from the on position ( FIG. 10 ) to the off position ( FIG. 2 ), the push rod 60 pulls the latch 70 . This causes the latch 70 to pivot against the urging force of the latch spring 34 and open the link hole 54 toward the upper side.

The driver link 50 pivots in the disconnecting direction of the lever 20 by the urging force from the return springs 55 and 56 , and stops when moved to contact the stopper pin 99 fixed to the engagement hole of the first cover 11 11b and the engagement hole 12c of the second cover 12 . The engaging hole 11 b of the first cover 11 and the engaging hole 12 c of the second cover 12 are formed close to the protrusion 96 b which is the opposite end of the retainer 96 to the retainer pivot 96 a. Driver link 50 includes a distal end 57 that contacts stop pin 99 . The distal end portion 57 approaches the engagement protrusion 53 of the push retainer 96 of the driver link 50 . Therefore, enlargement of the driver link 50 can be restricted. The stopper pin 99 is a rigid member and has, for example, higher rigidity than the retainer 96 . In a preferable example, the retainer 96 is a resin member, and the stopper pin 99 is a metal member. Therefore, although the driver link 50 urged by the return springs 55 and 56 contacts and pushes the stop pin 99, cracking or wear of the stop pin 99 is eliminated or reduced.

The protrusion 72 of the latch 70 pushes the fitting 41 in the breaking direction against the pushing force and pivots the fitting 41 . The latching spring 34 pushes the indicator 30 in the off direction and causes the indicator 30 to pivot. When the engagement protrusion 32 contacts the upper end portion 81 of the indicator latch 80 , the indicator 30 stops. Here, the normal area 31 a of the indicating portion 31 is exposed from the indicator window 17 .

When the driver link 50 pivots in the disengagement direction of the lever 20, the engagement protrusion 53 pushes the protrusion 96b on the distal end of the retainer 96 to the position shown in FIG. 2 . As described above, the driver link 50 contacts the stop pin 99 and limits further movement of the rod 20 in the off direction. Therefore, even when the coil spring 98 pivots the retainer 96 about the retainer pivot 96a in the turn-on direction of the lever 20 (clockwise in FIG. 2 ), the engagement protrusion 53 of the driver link 50 restricts the retainer 96 pivot.

Here, as shown in FIG. 13 , in the retainer 96 and the driver link 50 , the side surface S1 or the contact surface of the protrusion 96 b on the retainer 96 on the side in the connection direction and the engagement protrusion in the driver link 50 The distal end surfaces S2 of 53 are in contact with each other. Here, side S1 and distal surface S2 are substantially parallel to each other. Furthermore, the surfaces S1 and S2 extend perpendicular to the urging force of the coil spring 98 which pivots the retainer 96 in the switching direction of the lever 20 . In FIG. 13 , the angle θ between the plane RS parallel to the driving force of the coil spring and the side S1 is 90 degrees.

When the retainer 96 is urged by the coil spring 98 while being in contact with the engagement protrusion 53 , the retainer 96 is fixed and the movable core 97 is held at a position where the movable core 97 contacts the magnetic pole surface of the fixed core 93 .

The operation when the electromagnetic trip device 90 functions and switches the undervoltage circuit breaker from the ON state (FIG. 10) to the tripped state (FIG. 12) will now be described. Figure 11 shows the moment when the undervoltage trip occurs.

In the ON state (FIG. 10), when the excitation circuit detects that the voltage is lower than a predetermined set value (below the rated voltage (undervoltage state)), the excitation circuit turns off the switch connected in series with the solenoid coil 92 so that the undervoltage trips device trip.

This stops the supply of current to the electromagnetic coil 92 and eliminates the electromagnetic attraction force between the fixed core 93 and the movable core 97 . Therefore, as shown in FIG. 11, when the urging force of the coil spring 98 makes the retainer 96 pivot in the connection direction, the distal end surface or the contact surface 96e of the retainer 96 abuts against the latch 70 so that the latch 70 is in the OFF state. Pivot in the open direction. Also, the transmission end portion 62 of the thrust rod 60 moves away from the latch portion 71 and out of the link hole 54 .

As the transfer end 62 of the thrust lever 60 moves out of the link hole 54 (as shown in FIG. 12 ), the driver link 50, which is no longer supported by the thrust lever 60, is pushed by the return springs 55 and 56 and pivots in the disconnecting direction to Disconnect position. Also, the protrusion 72 of the latch 70 pushes the fitting 41 toward the upper side, and the fitting lever 42 drives the interruption mechanism of another circuit breaker so that the interruption circuit breaks the contact. This stops the supply of current to the load connected to the other circuit breaker and thereby protects the load device.

The holder 96 is pivoted in the ON direction of the lever 20 by the urging force of the coil spring 98 . However, the urging force of the return springs 55 and 56 is set larger than that of the coil spring 98 . Therefore, when the protrusion 96 b contacts the engagement protrusion 53 of the driver link 50 , the lever 20 cannot further pivot in the ON direction of the lever 20 .

When the driver link 50 is pivoted in the disconnecting direction of the lever 20 by the urging force of the return springs 55 and 56 , the engagement protrusion 53 of the driver link 50 pushes the protrusion 96 b of the holder 96 . As a result, the retainer 96 pivots from the position shown in FIG. 11 to the position shown in FIG. 12 in the breaking direction of the lever 20 . When the driver link 50 contacts the stop pin 99, the movement of the rod 20 in the opening direction is restricted. Therefore, even when the retainer 96 is pivoted by the coil spring 98 about the retainer pivot 96a in the turning-on direction of the lever 20 (clockwise in FIG. 12 ), the engagement protrusion 53 of the driver link 50 restricts the retainer 96 pivot.

As shown in FIG. 13 , when side S1 of retainer 96 contacts distal surface S2 of driver link 50 , side S1 is parallel to distal surface S2 . The two surfaces S1 and S2 extend perpendicular to the urging direction of the coil spring 98 which pivots the retainer 96 in the ON direction of the lever 20 .

When the retainer 96 is urged by the coil spring 98 while being in contact with the engagement protrusion 53 , the retainer 96 is fixed and the movable core 97 is held at a position where the movable core 97 contacts the magnetic pole surface of the fixed core 93 .

The protrusion 96c of the retainer 96 pushes the indicator latch 80 in the opening direction and pivots the latch 80 (refer to FIG. 3 ) to unlatch the indicator 30 . When the indicator 30 is unlocked, the indicator 30 receives the urging force of the lock spring 34 and pivots in the opening direction. The trip area 31 b of the indicating portion 31 is exposed from the indicator window 17 . Then, the lever 20 receives the urging force of the lever spring 25 and pivots in the opening direction. When the lever reaches the disengaged position, the transfer end 62 of the thrust rod 60 fits into the link hole 54 and moves to a position where the transfer end 62 engages the latch 71 . Here, the transmission end 62 of the thrust rod 60 is fitted into the connecting rod bore 54 surrounded by the driver connecting rod 50 and the locking element 70 . Thus, when the lever 20 is pivoted in the on direction to the on position, the state shown in FIG. 10 is obtained.

Advantages of this embodiment will now be described.

(1) The electromagnetic tripping device 90 includes a limit pin 99, when the movable magnetic core 97 contacts the fixed magnetic core 93 due to the thrust of the driver link 50, the limit pin limits the driver link against the thrust of the driver link 50. Movement of rod 50. This reduces the thrust applied to the retainer 96, limits plastic deformation of the retainer 96, and limits displacement of the driver link 50 from the rest position. As a result, the displacement of various movable elements is limited within the electromagnetic trip device 90 and the undervoltage circuit breaker including the electromagnetic trip device 90 . This stabilizes contact between elements and stabilizes voltage characteristics.

(2) The stopper pin 99 is located on the side of the protrusion 96 b of the holder 96 that receives the thrust from the driver link 50 . This restricts the displacement of the stopper pin 99 relative to the protrusion 96b. Therefore, the limit pin 99 allows the thrust of the driver link 50 to be received at a correct position, and the displacement of the driver link 50 is limited.

(3) The holder 96 is pivoted about the holder pivot 96 a by the coil spring 98 so as to move the fixed core 93 away from the movable core 97 . Also, the retainer 96 includes a side S1 that contacts the driver link 50 . The side S1 extends perpendicularly to the direction in which the coil spring 98 acts when it contacts the driver link 50 . Therefore, even when the retainer 96 contacts the driver link 50, the bending moment acting on the retainer 96 can be reduced. This inhibits plastic deformation of the retainer 96 and further limits displacement of the driver link 50 from the rest position. Also, the distal end portion 57 of the driver link 50 contacting the stopper pin 99 is positioned close to the engagement protrusion 53 of the driver link 50 . This limits the enlargement of the driver linkage 50 .

(4) The stopper pin 99 is separated from the covers 11 and 12 . Therefore, the covers 11 and 12 can be used with other circuit breakers that do not require the stop pin 99 .

It will be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention. In particular, it should be understood that the present invention may be embodied in the following forms.

The stopper pin 99 does not have to be fixed to the engagement holes 11 b and 12 c of the covers 11 and 12 . For example, the limit pin 99 can be integrally formed with the covers 11 and 12 in advance. This reduces the number of parts.

The stopper pin is not limited to the rod-shaped stopper pin 99 and may have any form of a protrusion like a plate.

In the above embodiments, the undervoltage circuit breaker is used as the circuit breaker. However, other circuit breakers such as overvoltage circuit breakers may be used as long as the circuit breaker includes the electromagnetic trip device 90 .

The above description is intended to be exemplary, and not restrictive. For example, the examples described above (or one or more aspects thereof) may be used in conjunction with each other. Other embodiments can be used (such as by a person skilled in the art upon reading the above description). Also, in the above Detailed Description, various features may be grouped together in order to streamline the invention. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims (9)

1. An electromagnetic tripping device, said electromagnetic tripping device comprising: coil spring; a first magnetic core inserted through the coil spring; A second magnetic core that is urged away from the first magnetic core by the coil spring, wherein the first magnetic core and the second magnetic core are configured such that the first magnetic core and the second magnetic core the cores are moved into contact with each other and moved away from each other by the urging force generated by the coil spring and the electromagnetic force generated by the first magnetic core; a pivoting magnetic core holder comprising a base end portion comprising a pivot and a distal end portion pushed by the thrust of the driver link, and when the first magnetic core generates an electromagnetic When a force is applied, the magnetic core holder pivots along a direction in which the first magnetic core and the second magnetic core approach each other; and a restricting portion that restricts movement of the driver link against a thrust force of the driver link when the core holder contacts or approaches the driver link and the first core contacts the second core . 2. The electromagnetic trip device according to claim 1, wherein the restricting portion is arranged close to a distal end portion away from the core holder pivot. 3. The electromagnetic trip device according to claim 1, wherein: the core holder is urged by a coil spring and pivots about a pivot in a direction in which the second core moves away from the first core; the core holder includes a contact surface that contacts the driver link; and The contact surface extends perpendicular to the direction of the urging force of the coil spring when the contact surface is in contact with the driver link. 4. The electromagnetic trip device according to claim 1, wherein contact of the limiting portion with the driver link limits a movable range of the driver link. 5. The electromagnetic trip device according to claim 1, wherein: the driver link is supported for pivoting about its base end; The driver link includes a distal portion that contacts the restricting portion when the driver link pivots; The driver link includes an engaging protrusion between a base end and a distal end of the driver link, wherein the engaging protrusion contacts the distal end of the core holder; and The restricting portion is a rigid element that contacts the distal end of the driver link when the engagement protrusion of the driver link contacts the distal end of the core holder. 6. A circuit breaker comprising the electromagnetic tripping device according to any one of claims 1 to 5. 7. The circuit breaker of claim 6, further comprising: a lever supported to pivot between an on position in which the movable contact contacts the fixed contact and an off position in which the movable contact move away from the fixed contact; and an interruption mechanism connected directly or indirectly to the lever, wherein when the lever pivots, the interruption mechanism causes the movable contact to move away from the fixed contact, Wherein the electromagnetic trip device is configured to move the movable contact away from the fixed contact when a predetermined circuit state is detected. 8. A combined circuit breaker assembly comprising: a first circuit breaker which is a circuit breaker according to claim 6; and A second circuit breaker connected to the first circuit breaker. 9. The combined circuit breaker assembly (2) according to claim 8, wherein each of the first circuit breaker and the second circuit breaker includes a lever; and The bars of the first and second circuit breakers are connected via a connecting bar.