CN104241048A - Electromagnetic tripping device and breaker - Google Patents

Abstract

The invention discloses an electromagnetic tripping device and a circuit breaker. The electromagnetic tripping device (90) includes a coil spring (98), a first core (93) and a second core (97). The first core and the second core are configured such that the first core and the second core move to contact each other and move away from each other by an urging force generated by the coil spring and an electromagnetic force generated by the first core. A core holder (96) supports the second core. The core holder includes a distal end (96c) and a base end including a pivot point (96b). The core holder pivots about the pivot point when the distal end is pushed. The core holder pivots so that the second core approaches the first core when the first core generates an electromagnetic force. A biasing element (B) is located between the core holder and the second core to bias the second core towards the first core.

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 condition (refer to, for example, Japanese Laid-Open Patent Publication No. 2000-231869). The circuit breaker may be, for example, a molded case circuit breaker, an earth leakage circuit breaker, an overvoltage circuit breaker, an undervoltage circuit breaker, or the like. Molded case circuit breakers interrupt the circuit when they detect a fault current caused by a short circuit or overload. Earth leakage circuit breakers interrupt a circuit when a current leak is detected. The overvoltage circuit breaker interrupts the circuit when the voltage of the circuit becomes higher than a predetermined upper limit voltage. The undervoltage circuit breaker interrupts the circuit when the voltage of the circuit becomes lower than a predetermined lower limit voltage. Multifunction circuit breakers combining different types of circuit breakers are also known.

A general circuit breaker includes: a switch mechanism that closes and opens contacts; a lever that is used to manually close and open the contacts; and an electromagnetic trip device that opens the contacts through the switch mechanism.

The circuit breaker of the 869' publication includes an electromagnetic trip device. The connecting rod protrudes from the housing of the electromagnetic trip unit. The connecting rod is installed in the housing of the circuit breaker coupled 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: an electromagnetic coil wound around a reel; a first core extending through a hole of the reel; a second core attracted to a magnetic pole of the first core when current flows through the electromagnetic coil; and a coil spring , which urges the second core away from the poles of the first core.

When power is supplied to the electromagnetic coil in the above electromagnetic trip device, the first core magnetically attracts the second core so that the cores abut each other. However, the inventors of the present application have noticed that the magnetic force of the first core may not be sufficient to secure the abutment of the second core against the biasing force of the coil spring.

Contents of the invention

An object of the present invention is to provide an electromagnetic trip device and a circuit breaker for securing the adjacency of a first core and a second core.

An aspect of the present invention is an electromagnetic trip device including: a coil spring; a first core inserted through the coil spring; and a second core separated from the first core by the coil spring. The first core and the second core are configured such that the first core and the second core move to contact each other and move away from each other by the urging force generated by the coil spring and the electromagnetic force generated by the first core. The core holder supports the second core. The core holder includes a distal end and a base end including a pivot point. The core holder is configured to pivot about a pivot point when the distal end is pushed, and the core holder pivots such that the second core approaches the first core when the first core generates an electromagnetic force. A biasing element is located between the core holder and the second core to bias the second core towards the first core.

An aspect of the present invention is to provide an electromagnetic trip device ensuring adjacency of a first core and a second core.

In a particular example, the biasing element includes an arched leaf spring, and the arched leaf spring includes two ends that engage the core holder and a curved surface that bulges toward the second core.

In a particular example, the core holder includes a core position limiting unit that limits displacement of the second core against a biasing force applied to a biasing element of the second core.

In a particular example, the biasing element biases the second core such that the second core continuously contacts at least one of the first core and the core position limiting unit.

In a specific example, when the second core moves away from the first core, the biasing element biases the second core such that the second core contacts the core position limiting unit, and when the second core contacts the first core, the biasing element The second core is allowed to elastically move away from the core position restricting portion.

Another aspect of the invention provides a circuit breaker comprising a contact arrangement according to one or more of said one aspect and the above examples.

In a particular example, the circuit breaker includes: a lever supported to pivot between an ON position in which the movable contact is in contact with the fixed contact and an OFF position in which the movable contact moves away from the fixed contact; and An interrupt mechanism, directly or indirectly connected to the joystick, wherein the interrupt mechanism moves the movable contact away from the first contact when the joystick pivots. 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 an embodiment, a combined circuit breaker assembly comprises: a first circuit breaker which is the circuit breaker according to another aspect; a second circuit breaker coupled to the first circuit breaker.

In a particular example, each of the circuit breakers and the other circuit breakers include a lever, the lever of the circuit breaker and the further circuit breaker being joined 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 present invention, together with its objects and advantages, may be better understood by referring to the following description of presently preferred embodiments together with the accompanying drawings, in which:

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

Figure 2 is a left side view of the circuit breaker in the OFF state;

Fig. 3 is a left 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 side view of the electromagnetic tripping device;

Fig. 8 is a side view of the electromagnetic tripping device;

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

Fig. 10 is a left view of the circuit breaker in the ON state;

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

Fig. 12 is a left side view of the circuit breaker when undervoltage tripping occurs;

Fig. 13 is a schematic diagram showing a driver connector and a core holder in contact with each other;

Figure 14 is a left side view of the holder; and

Figure 15 is a cross-sectional view of a retainer; and

16A and 16B illustrate a combination circuit breaker assembly including the circuit breaker of FIG. 1 and additional circuit breakers.

Detailed ways

An embodiment of an electromagnetic trip device and a circuit breaker including the same will now be described. The circuit breaker may be an undervoltage circuit breaker 1 that interrupts the circuit when the voltage of the circuit becomes lower than a predetermined lower limit voltage. Undervoltage circuit breakers can 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 11 a of the first cover 11 is connected with the open end 12 a of the second cover 12 to define an internal compartment in 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 joystick 20 , the indicator 30 , the interruption mechanism 40 , the electromagnetic trip device 90 and the circuit board 14 are arranged in an internal compartment of the housing 10 . The circuit board 14 includes an excitation circuit. A lever gate 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 cooperating piece 41 , a driver link 50 (movable link), a thrust rod 60 and a latch 70 . The housing 10 accommodates an indicator 30 indicating the operating condition of the undervoltage circuit breaker in an indicator window 17 and an indicator latch 80 .

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

A connecting rod 23 extends from a lever protrusion 22 parallel to the first pivot axis 18 . The connecting rod 23 may be joined to the operating rod 20A of another circuit breaker 1A to form a combined circuit breaker assembly 2 as shown in FIGS. 16A and 16B . Thus, the connecting rod 23 pivots the operating lever 20 of the undervoltage circuit breaker 1 together with the operating lever 20A of the other circuit breaker 1A. In addition, a circuit breaker (which may be plural) may be incorporated into the circuit breaker 1 and/or another circuit breaker 1A. In the illustrated example, the lever protrusion 22 is in the ON position (closed position) when moved away from the terminal unit 13 and in the OFF position (opened position) when moved close to the terminal unit 13 . The joystick 20 is continuously urged away from the ON position by eg a joystick spring 25 . In the following description, the direction in which the joystick 20 pivots from the OFF position shown in FIG. 2 to the ON position shown in FIG. The direction in which the ON position pivots to the OFF position (the counterclockwise direction in FIG. 2 ) is referred to as the OFF direction.

The cooperating piece 41 is pivotally supported by the third pivot shaft 43 . The cooperating piece 41 holds one end of a cooperating rod 42 which may be a metal rod. The other end of the cooperating rod 42 protrudes out of the second cover 12 through the slit 12b, and is coupled to a cooperating piece of another circuit breaker.

The driver link 50 , the latch 70 and the indicator 30 pivot about the second pivot axis 19 . The second pivot shaft 19 includes both 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, continuously urge the driver connection 50 in the OFF direction.

The return springs 55 and 56 each have one end coupled to the first cover 11 and the other end coupled to the driver connector 50 . The lever spring 25 continuously urges the lever 20 in the OFF direction. Indicator latch spring 83 , which may be a torsion spring, continuously urges indicator latch 80 in the ON direction.

The thrust rod 60 may be a metal round bar bent into a U shape. The thrust rod 60 includes an operating end 61 and a transmitting end 62 . The operating end 61 is installed in the connection hole 24 of the joystick 20 . The transmission end 62 is arranged in the connection hole 54 formed by the engagement part 51 of the driver connection 50 and the latch part 71 of the latch 70 . In this case, the thrust rod 60 is locked by the latch 70 (locked state). In the locked state, the thrust rod 60 transmits the movement of the operating lever 20 to the drive connection 50 .

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

A fourth pivot shaft 82 pivotally supports the indicator latch 80 . The indicator latch spring 83 continuously urges the indicator latch 80 in the OFF direction. Indicator latch 80 includes an upper end 81 and an underside of indicator 30 includes engagement protrusion 32 . When the upper end 81 of the indicator latch 80 contacts the engagement protrusion 32 of the indicator 30 , further rotation of the indicator 30 in the OFF direction is restricted. Indicator 30 includes a distal end defining an indicating portion 31 that indicates a circuit condition. The indication portion 31 includes an upper surface divided into two regions. The side of the indicating portion closer to the lever 20 defines a normal area 31a, and the side of the indicating portion farther from the operating lever 20 defines a trip area 31b. One of the areas 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 energizing circuit that deactivates the solenoid 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 spool 91 , an electromagnetic coil 92 , a fixed core 93 , a spacer 110 , 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 core 93 may be formed by a plate of magnetic material (iron). In the illustrated embodiment, the fixed core 93 is U-shaped and includes a first or upper arm 94 and a second or lower arm 95 . The lower arm 95 is fitted in the hole of the reel 91 . One end of the spool 91 includes an inlet flange 91a, and the other end of the spool 91 includes an outlet flange 91b. The lower arm 95 of the stationary core 93 includes a distal end exposed from the outlet flange 91b of the reel 91 . The coil spring 98 is held on the upper arm 94 of the fixed core 93 .

As shown in Figures 14 and 15, the holder 96 includes a core storage compartment 96a and a holder pivot shaft 96b. The core storage compartment 96a is shaped to accommodate a movable core 97 which may be a magnetic plate. A holder pivot shaft 96b is arranged on one end of the core storage compartment 96a. Holder pivot axis 96b may be referred to as a pivot point. The holder 96 may be a synthetic resin member.

The core storage compartment 96a includes: a bottom wall 101 formed of an elongated quadrangular plate; and first to fourth side walls 102-105 surrounding and extending orthogonally to the bottom wall 101 . The first side wall 102 is substantially parallel to the second side wall 103 . The third side wall 104 is substantially parallel to the fourth side wall 105 . The third side wall 104 and the fourth side wall 105 are substantially orthogonal to the first side wall 102 and the second side wall 103 .

The core storage compartment 96a includes an opening 106 . The movable core 97 contacts the arms 94 and 95 of the fixed core 93 through the opening 106 . The holder 96 includes stopper plates 107 and 108 . The stopper plates 107 and 108 partially close the opening 106 . In the example shown, stop plates 107 and 108 are located in a first portion of opening 106 in core storage compartment 96a. The stopper plate 107 is formed at an angle intersecting the first side wall 102 and the third side wall 104 . The stopper plate 108 is formed at an angle intersecting the second side wall 103 and the third side wall 104 . The stopper plates 107 and 108 are each spaced apart from the fourth side wall 105 . Preferably, the stop plates are spaced apart from each other to form a slot between the stop plates 107 and 108 . The slot is shaped to accommodate one arm of the stationary core (eg, upper arm 94). In one example, the movable core 97 is allowed to contact the lower arm 95 of the stationary core 93 through a second portion of the opening 106 in the core storage compartment 96a, which is the portion of the opening 106 other than the first portion.

The holder pivot shaft 96b extends toward the outside from the first side wall 102 and the second side wall 103 . The holder pivot shaft 96b is rotatably supported by the outlet flange 91b. The holder 96 pivots about a holder pivot shaft 96b. This makes the movable core 97 far from the movable core 97 and the two arms 94 and 95 of the fixed core 93 at the position where the movable core 97 contacts the distal end surfaces (magnetic pole surfaces) of the two arms 94 and 95 of the fixed core 93. Movement between positions where the end surfaces (pole surfaces) separate.

Referring to FIGS. 6 to 8 , a protrusion 96c protrudes from a distal end portion of the holder 96 or an end portion of the holder 96 opposite to the holder pivot shaft 96b. When the holder 96 pivots about the holder pivot shaft 96b, the protrusion 96c pushes the engagement protrusion 53 of the driver link 50 and rotates the driver link 50 in the ON direction.

Referring to FIG. 15 , a biasing element B is arranged between the movable core 97 and the bottom wall 101 in the core storage compartment 96 a of the holder 96 . The biasing element B biases the movable core 97 toward the fixed core 93 . In the example shown, the biasing element B is an arched leaf spring comprising two ends engaging the core holder and a curved surface bulging towards the second core 97 .

The stopper plates 107 and 108 contact the movable core 97 biased by the biasing member B, and restrict the movement or displacement of the movable core 97 . Biasing element B cooperates with stop plates 107 and 108 to limit separation of movable core 97 from core storage compartment 96a. The stopper plates 107 and 108 function as core position limiting units.

The biasing member B biases the movable core 97 so that the movable core continuously contacts the stopper plates 107 and 108 or the fixed core 93 . For example, when the movable core 97 is separated from the fixed core 93 , the biasing member B biases the movable core 97 so that the movable core 97 contacts the stopper plates 107 and 108 . When the movable core 97 contacts the fixed core 93 , the biasing member B allows the movable core 97 to elastically move away from the stopper plates 107 and 108 .

Referring to FIGS. 8 and 9 , a spacer 110 is coupled to the fixed core 93 to reduce a gap between the outer surface of the fixed core 93 and the inner contour of the coil spring 98 . The spacer 110 includes a plurality of elongated members 111 and 112 extending in the axial direction of the coil spring 98 . In the example shown, the elongate members 111 and 112 are two plates facing each other and extending along the upper arm 94 of the fixed core 93 . The bridging member 113 connects the elongated members 111 and 112 . The contact of the bridge member 113 with the back surface 93 a of the fixed core 93 axially positions the spacer 110 relative to the fixed core 93 . The spacer 110 is shaped and sized so as not to generate a frictional force that hinders expansion and contraction of the coil spring 98 . The arrangement of the spacer 110 in the gap between the outer surface of the fixed 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 , 3 and 10 to 12 . The operation of the undervoltage circuit breaker when switching from the OFF state of FIG. 2 to the ON state of FIG. 10 will first be described.

When the operating lever 20 is pivoted in the ON direction from the OFF position ( FIG. 2 ) to the ON position ( FIG. 10 ), the thrust rod 60 pushes the engagement part 51 of the driver link 50 and pivots the driver link 50 in the ON direction. .

The straight line connecting the first pivot axis 18 of the operating lever 20 with the transmission end 62 of the thrust rod 60 is called a switching boundary line. As the operating lever 20 pivots in the ON direction, when the operating end 61 of the thrust lever 60 exceeds the switching boundary line, the transmission end 62 of the thrust lever 60 stops while being pushed against the engagement member 51 . Here, the joystick 20 and the thrust lever 60 are kept at the ON position, and the undervoltage circuit breaker is kept 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 pivots and moves the indicator 30 in the ON direction to indicate the reset position. In this case, the indicator latch spring 83 urges and moves the indicator latch 80 to a position where the indicator latch 30 latches the indicator 30 . In addition, the cooperating piece 41 pivots in the ON direction as the driver link 50 pivots, and moves the cooperating pieces of other circuit breakers together with the cooperating 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 . In this way, the movable core 97 is attracted to the fixed core 93 . The holder 96 pivots to the ON position against the urging force of the coil spring 98 . In this way, the protrusion 96c at the distal end of the retainer 96 is separated from the driver connector 50 .

The operation of the undervoltage circuit breaker when switching from the ON state to the OFF state will now be described.

When the lever 20 is pivoted in the OFF direction from the ON position ( FIG. 10 ) to the OFF position ( FIG. 2 ), the thrust rod 60 pulls the latch 70 . This pivots the latch 70 against the urging force of the latch spring 34 and opens the connection hole 54 toward the upper side.

The driver link 50 is pivoted in the OFF direction of the operating lever 20 by the urging force from the return springs 55 and 56 , and when moved to the engagement hole 11 b fixed to the first cover 11 and the engagement hole 12 c of the second cover 12 Stop when limit pin 99 contacts. The engagement hole 11 b of the first cover 11 and the engagement hole 12 c of the second cover 12 are formed near a protrusion 96 c that is an end portion of the holder 96 opposite to the holder pivot shaft 96 b. The driver connector 50 includes a distal portion 57 that contacts the stop pin 99 . The distal portion 57 is adjacent to the engagement protrusion 53 of the driver connector 50 that pushes the holder 96 . Therefore, enlargement of the driver connector 50 can be restricted. The stopper pin 99 is a rigid member, and has higher rigidity than, for example, that of the holder 96 . In a preferable example, the holder 96 is a resin member, and the stopper pin 99 is a metal member. Thus, although the driver link 50 urged by the return springs 55 and 56 contacts and pushes the stop pin 99 , chipping or wear of the stop pin 99 is eliminated or reduced.

The protrusion 72 of the latch 70 pushes the cooperating piece 41 against the urging force and pivots the cooperating piece 41 in the OFF direction. The latch spring 34 urges and pivots the indicator 30 in the OFF direction. When the engagement protrusion 32 contacts the upper end 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 OFF direction of the joystick 20 , the engagement protrusion 53 pushes the protrusion 96 c on the distal end of the holder 96 to the position shown in FIG. 2 . As described above, the driver link 50 contacts the stop pin 99 and limits further movement in the OFF direction of the joystick 20 . Therefore, even when the coil spring 98 pivots the holder 96 about the holder pivot shaft 96b in the ON direction (clockwise direction in FIG. 2 ) of the operating lever 20, the engagement protrusion 53 of the driver link 50 restricts the holder. 96 pivots.

Here, as shown in FIG. 13 , in the holder 96 and the driver connector 50 , the side surface S1 or the contact surface on the ON direction side of the protrusion 96 c on the holder 96 is far from the engaging protrusion 53 in the driver connector 50 . The end surfaces S2 are in contact with each other. Here, the side surface S1 and the distal surface S2 are substantially parallel to each other. Further, the surfaces S1 and S2 extend perpendicular to the urging force of the coil spring 98 that pivots the holder 96 in the ON direction of the joystick 20 . In FIG. 13 , an angle θ between a plane RS parallel to the urging force of the coil spring and the side surface S1 is 90 degrees.

When the holder 96 is urged by the coil spring 98 while being in contact with the engagement protrusion 53 , the holder 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 .

In this case, the biasing element B urges the movable core 97 towards the fixed core 93 . This further ensures that the movable core 97 is in contact with (adjacent to) 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 an undervoltage trip occurs.

In the ON state (Fig. 10), when the excitation circuit detects that the voltage is lower than the predetermined set value (undervoltage state) lower than the rated voltage, the excitation circuit closes the switch connected in series to the electromagnetic coil 92, so that the undervoltage circuit breaker trip.

This stops the supply of electric current to the electromagnetic coil 92 and cancels the electromagnetic attractive force between the fixed core 93 and the movable core 97 . As a result, as shown in FIG. 11, when the urging force of the coil spring 98 pivots the retainer 96 in the ON direction, the distal end surface or contact surface 96e of the retainer 96 contacts against (abut against) the latch 70. to pivot the latch 70 in the OFF direction. Furthermore, the transmission end 62 of the thrust rod 60 moves away from the latch member 71 and moves out of the connection hole 54 .

Since the transmission end 62 of the thrust rod 60 moves out of the connection hole 54, as shown in FIG. Pivot to OFF position. Furthermore, the protrusion 72 of the latch 70 pushes the cooperating piece 41 towards the upper side, and the cooperating lever 42 drives the interrupting mechanism of the other circuit breaker so that the interrupting circuit breaks the contacts. In this way, the supply of current to the loads connected to other circuit breakers is stopped, thereby protecting the load devices. The holder 96 pivots in the ON direction of the operating lever 20 by the biasing 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 c contacts the engaging 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 OFF 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 c of the holder 96 . As a result, the holder 96 pivots in the OFF direction of the operating lever 20 from the position shown in FIG. 11 to the position shown in FIG. 12 . When the driver link 50 contacts the stop pin 99, the movement of the joystick 20 in the OFF direction is restricted. Therefore, even if the retainer 96 is pivoted in the ON direction (clockwise in FIG. 12 ) of the operating lever 20 around the retainer pivot shaft 96b by the coil spring 98, the engagement protrusion 53 of the driver link 50 restricts the retainer. 96 pivots.

As shown in FIG. 13 , when the side surface S1 of the holder 96 contacts the distal surface S2 of the driver connector 50 , the side surface S1 is parallel to the distal surface S2 . Both surfaces S1 and S2 extend perpendicular to the urging direction of the coil spring 98 that pivots the holder 96 in the ON direction of the operating lever 20 .

When the holder 96 is urged by the coil spring 98 while being in contact with the engagement protrusion 53 , the holder 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 .

In this case, the biasing element B urges the movable core 97 towards the fixed core 93 . This further ensures that the movable core 97 is in contact with (adjacent to) the magnetic pole surface of the fixed core 93 .

The protrusion 96c of the holder 96 pushes and pivots the indicator latch 80 in the OFF direction (refer to FIG. 3 ) to unlock the indicator 30 . When the indicator 30 is unlocked, the indicator 30 is urged by the latch spring 34 and pivots in the OFF direction. The trip area 31b of the indicating portion 31 is exposed from the indicator window 17 . Then, the lever 20 is urged by the lever spring 25, and pivots in the OFF direction. When the operating lever reaches the OFF position, the transmission end 62 of the thrust rod 60 is installed in the connection hole 54 and moves to a position where the transmission end 62 engages with the latch member 71 . Here, the transmission end 62 of the thrust rod 60 is mounted in the connection hole 54 surrounded by the driver connection 50 and the latch 70 . Therefore, when the joystick 20 is pivoted to the ON position in the ON direction, the state shown in FIG. 10 is obtained.

Advantages of the embodiments will now be described.

(1) The electromagnetic trip device 90 includes a biasing member B that biases the movable core 97 toward the fixed core 93 . This ensures the contact of the movable core 97 with the fixed core 93 .

(2) In a preferred example, the biasing member B is an arched leaf spring. The leaf spring can be easily installed between the movable core 97 and the core storage compartment 96 a of the holder 96 . Furthermore, the leaf spring minimizes the space for housing the biasing element B between the movable core 97 and the core storage compartment 96 a of the holder 96 . This is preferable when downsizing the holder 96 .

(3) In a preferred example, the holder 96 includes stopper plates 107 and 108 . The stopper plates 107 and 108 are in contact with the movable core 97 biased by the biasing member B, and restrict the movement or displacement of the movable core 97 .

(4) In the reference example, a resin plate is cut from a part of the holder 96 to bias the movable core 97 . In the reference example, the biasing force of the resin plate was reduced in a relatively short time. In a preferred example, the holder 96 is formed of resin, and the biasing member B is a metal member having higher rigidity than the holder 96 . Therefore, the biasing force of the biasing member B can be maintained for a long time. This allows the movable core 97 and the fixed core 93 to remain in contact for a long time.

The above embodiments can be modified as described below.

The number and location of stop plates 107 and 108 may vary. For example, the stop plates 107 and 108 may be arranged in the second portion of the opening 106 instead of or in addition to the first portion of the opening 106 .

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

The above description is intended to be illustrative rather than limiting. For example, the above examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments may be utilized, such as by one of ordinary skill in the art after reviewing the above embodiments. In addition, in the above detailed description, various features may be combined with each other to simplify the present disclosure. This should not be interpreted as saying that an unclaimed disclosed feature is essential to any claim. Furthermore, inventive subject matter may be found in less than all features of a specifically disclosed embodiment. Thus, the claims that follow herein are incorporated into the Detailed Description, with each claim item standing on its own as a separate embodiment. The scope of the invention should be determined with reference to the claims, along with the full scope of equivalents to which such claims are entitled.

Claims (9)

1. An electromagnetic tripping device, comprising: coil spring; a first core inserted through the coil spring; a second core separated from the first core by a coil spring, wherein the first core and the second core are configured such that the first core and the second core pass an urging force generated by the coil spring and an electromagnetic force generated by the first core moving to touch each other and moving away from each other; a core holder supporting a second core, wherein the core holder includes a distal end and a base end including a pivot point, the core holder being configured to pivot about the pivot point when the distal end is pushed , and the core holder pivots so that the second core approaches the first core when the first core generates an electromagnetic force; and A biasing element is positioned between the core holder and the second core to bias the second core toward the first core. 2. The electromagnetic tripping device according to claim 1, characterized in that, the biasing element comprises an arched leaf spring, and The arched leaf spring includes both ends engaged with the core holder and a curved surface bulging toward the second core. 3. The electromagnetic trip device according to claim 1, wherein the core holder includes a core position limiting unit that limits displacement of the second core against a biasing force of a biasing element applied to the second core. 4. The electromagnetic trip device according to claim 3, wherein the biasing member biases the second core such that the second core continuously contacts at least one of the first core and the core position limiting unit. 5. The electromagnetic tripping device according to claim 4, characterized in that, When the second core moves away from the first core, the biasing member biases the second core such that the second core contacts the core position limiting unit, and The biasing member allows the second core to elastically move away from the core position limiting portion when the second core contacts the first core. 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, 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 moves away from the fixed contact; and an interruption mechanism connected directly or indirectly to the joystick, wherein the interruption mechanism moves the movable contact away from the first contact when the joystick pivots, Wherein, the electromagnetic trip device is configured to move the movable contact away from the fixed contact when a predetermined circuit condition is detected. 8. A combination circuit breaker assembly, comprising: a first circuit breaker which is a circuit breaker according to claim 6; A second circuit breaker coupled to the first circuit breaker. 9. The combined circuit breaker assembly of claim 8, wherein: each of the first circuit breaker and the second circuit breaker includes a joystick; and The operating levers of the first and second circuit breakers are combined via a connecting rod.