JP2003317601A - Pull-out device of circuit breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pull-out device of a circuit breaker which will hardly malfunction by an instantaneous inrush current. <P>SOLUTION: An overcurrent pull-out device 47 is provided with a first core 57 of a cross-section U shape with a bimetal arranged between both side pieces 57a and a second core 58 opposed to the tip faces of the both side pieces 57a with at least its part arranged in a separated state from the both side pieces 57a at a closed-pole state, and the second core 58 is equipped with a latch part 60 keeping a switching mechanism in a locked state. A leaf spring 59 has integrated a first spring part 59A linking a bimetal 46 and the second core 58 and a second spring part 59B linking the first core 57 and the second core 58, of which, the first spring part 59A biases the second core 58 toward a direction away from the first core 57, and at the same time, the second spring part 59B biases the first core 57 toward a direction away from the second core 58 with a biasing force smaller than that of the first spring part 59A. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a trip device for a circuit breaker for forcibly opening contacts when an overcurrent or a short circuit current flows.

[0002]

2. Description of the Related Art In recent years, as a circuit breaker used in a branch circuit of a house, a branch circuit has been used in place of a breaker for a distribution board for a house (see JIS C 8370) which is generally called a safety breaker. Wiring circuit breaker with a momentary interruption function for cord short-circuit protection that can instantly interrupt the circuit even with a relatively small short-circuit current, such as when the power cord of an electrical device connected to a power source is short-circuited due to damage or deterioration of the coating (Japan Electrical Machinery Manufacturers Association standard 1477) is used.

The above-mentioned wiring breaker with an instantaneous breaking function for short-circuit protection (hereinafter abbreviated as "circuit breaker") is equipped with a trip device having a higher sensitivity than that of a conventional safety breaker.
The sensitivity current value (the magnitude of the short-circuit current at which the trip device performs the trip operation) has an upper limit of 350 A in the above standard,
It is set to a value with a lower limit of a current value (for example, about 8 times the rated current) at which the tripping operation is not performed in the overflow test defined in JIS C8370.

An example of such a circuit breaker with an instantaneous breaking function for protecting a cord short circuit is disclosed in Japanese Patent Laid-Open No. 2002-2541.
5 (a) and 5 (b), a trip device for this circuit breaker is shown in FIGS. 22 (a) shows the closed state, and FIG. 22 (b) shows the opened state due to a short circuit current.

This tripping device 200 is inserted into an energizing path and has a bimetal 201 having one end in the longitudinal direction as a fixed end and the other end as a free end, and a pair of bimetals arranged on both sides in the width direction. Side piece 202a having two side pieces 202a
02a formed into a shape in which one surface of the bimetal 201 in the thickness direction is connected, and a second iron core 202 surrounding one surface and both side surfaces of the bimetal 201 in the thickness direction;
1 and the 1st iron core 203 arrange | positioned at the other surface side of the thickness direction.

The bimetal 201 is inserted into a space surrounded by the U-shaped portion of the second iron core 202 and the first iron core 203, and the bimetal 20 is energized as the bimetal 201 is energized.
The magnetic flux generated around the first core 202 and the second core 202
It goes through 03. The second iron core 202 is formed with a latch projection 202b that locks one end of an operating plate 204 of an opening / closing mechanism (not shown), and the second iron core 202 is connected to the bimetal 201 via a leaf spring 205. . The magnetic pole surface 202c at the tip of each side piece 202a of the second iron core 202 faces the first iron core 203, and in the state where no current flows in the bimetal 201, FIG.
As shown in FIG. 3, only the lower end of the magnetic pole surface 202c has the first iron core 2
It is in contact with 03. Further, the upper end portion of the first iron core 203 is in contact with a positioning portion (not shown) provided on the body.

When an excessive current such as a short-circuit current flows through this circuit breaker, the bimetal 20 inserted in the current-carrying path.
A short-circuit current flows in No. 1 and a magnetic field generated around the bimetal 201 generates an attractive force between the second iron core 202 and the first iron core 203. At this time, the magnetic pole surface 2 of the second iron core 202
Since the lower end of 02c is in contact with the first iron core 203,
A suction force is generated between the upper end of the magnetic pole surface 202c and the first iron core 203, so that the second iron core 20 as shown in FIG.
The upper part of 2 moves to the side of the first iron core 203, whereby the latched state between the operating plate 204 and the latch protrusion 202b is released, and the contact is forcibly opened by the opening / closing mechanism.

[0008]

The operation characteristics of the trip device 200 having the above-mentioned structure will be described with reference to FIGS. 23 (a) to 23 (e). FIG. 23 (a) shows the current waveforms of various currents flowing in the energization path. In FIG. 23 (a), the letter a shows the waveform of the motor starting current that flows when the motor is started when the motor is connected to the load, and b shows the overcurrent test. A half-wave current waveform applied at the time, C is a half-wave current waveform applied at the time of the cord short-circuit test, and D is a half-wave current waveform applied at the time of the short-circuit test. 23 (b) shows the displacement of the second iron core 202 when the motor starting current is applied, and FIG.
(D) and (e) show the displacement of the second iron core 202 when the overcurrent test, the cord short-circuit test, and the short-circuit test are performed, respectively. The dotted lines in FIGS. 23B to 23E indicate the position of the first iron core 203, and the second iron core 202 and the first iron core 20.
When the distance between the actuator 3 and the actuator 3 reaches a predetermined distance, the operating plate 204
The latched state between the latch projection 202b and the latch projection 202b is released.

In the case of the overcurrent test, the overcurrent applied during the test is smaller than the operating current Ith of the second iron core 202, and the attraction force generated between the second iron core 202 and the first iron core 203 is a plate. Since it is smaller than the biasing force of the spring 205,
As shown in FIG. 3C, the second iron core 202 is replaced by the first iron core 203.
It doesn't move to the side.

In the case of the cord short-circuit test, the cord short-circuit current applied during the test exceeds the operating current Ith of the second iron core 202. Therefore, as shown in FIG. 23 (d), when the cord short-circuit current exceeds the operating current Ith. Leaf spring 2 at (time t2)
The second iron core 202 resists the urging force of the first iron core 2
Start moving to the 03 side, and the second iron core 202 and the first iron core 20
When the distance between the operating plate 20 and
4 is released from the latched state with the latch projection 202b, and the contact is forcibly opened by the opening / closing mechanism.

Further, in the case of the short circuit test, a current (for example, about 2500 A) larger than the cord short circuit current flows,
As shown in FIG. 23E, at time t3 earlier than in the case of the cord short circuit test, the second force is applied against the biasing force of the leaf spring 205.
When the iron core 202 starts moving to the first iron core 203 side and the distance between the second iron core 202 and the first iron core 203 reaches a predetermined distance, the latched state between the operating plate 204 and the latch protrusion 202b is released. The contacts are forcibly opened by the opening / closing mechanism.

On the other hand, when a motor is connected to the load,
As shown in FIG. 23E, when the motor is started, a rush current of a cord short circuit current (about 350 A) or more flows, and the second iron core 20
Since a current that exceeds the operating current Ith of 2 instantaneously flows,
Although it is not a short-circuit current, the leaf spring 20
The second iron core 202 resists the urging force of the first iron core 20.
When the distance between the second iron core 202 and the first iron core 203 reaches a predetermined distance, the operation plate 204 and the latch protrusion 202b are released from the latched state and the contacts are forcibly opened. There was a problem of being poled.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a trip device for a circuit breaker which is unlikely to malfunction due to an instantaneous rush current.

[0014]

In order to achieve the above object, in the invention of claim 1, the contact inserted in the energizing electric path between the power source and the load, and the contact is opened when the contact is closed. Used in a circuit breaker equipped with an opening and closing mechanism that stores the force of the direction and puts it in the locked state and forcibly opens the contact by the force when the locked state is released. A trip device for a circuit breaker that releases the locked state and forcibly opens the contacts when a large current such as a short-circuit current or overload current flows, and has a shape in which one end of a pair of side pieces is connected. A first iron core that is formed and has a part of a conduction path disposed between both side pieces, and a first iron core that faces the other end side of the both side pieces and that is at least partially spaced apart from the both side pieces in the closed state. 2 iron cores, the second iron core is provided with a locking portion for locking the opening / closing mechanism, The first iron core is biased in the direction away from the second iron core, and the second iron core is biased in the direction away from the first iron core by a biasing force larger than the biasing force by the first biasing means. And a second urging means for preventing the urging force of the first and second urging means from adsorbing the first iron core and the second iron core when a large current flows through the energizing circuit, thereby forming an opening / closing mechanism. It is characterized in that the contact is forcibly opened by releasing the locked state with the locking portion.

According to a second aspect of the invention, in the first aspect of the invention, in the closed state, the first core and the second core are in contact with each other on one end side of the facing surface and separated from each other on the other side of the facing surface. When the other end side of the facing surface of the first iron core is attracted to the second iron core side and moved to a predetermined position, the other end side of the facing surface of the first iron core comes into contact and moves further toward the second iron core side. It is characterized in that the body is provided with a positioning portion for restricting movement.

According to a third aspect of the present invention, in the first aspect of the invention, the facing surfaces of the first core and the second core are separated from each other in the closed state, and the first core and the second core are in contact with one end side of the facing surface of the first core. It is characterized in that the container body is provided with a positioning portion for rotating the other end side of the facing surface of the first iron core to the second iron core side with the contact portion as a fulcrum.

According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, the energizing circuit is made of bimetal whose free end side is displaced by an overload current, and the second biasing means is made of bimetal. It is characterized by comprising a first leaf spring connecting the end and the second iron core.

According to a fifth aspect of the invention, in the fourth aspect of the invention, the first urging means comprises a second leaf spring connecting the first core and the second core. .

The invention of claim 6 is characterized in that, in the invention of claim 5, the first leaf spring and the second leaf spring are continuously and integrally formed from one spring material.

According to a seventh aspect of the invention, in any one of the first to third aspects of the invention, the first biasing means and the second biasing means are separate members.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 shows Embodiment 1 of the present invention.
~ It demonstrates based on FIG. The circuit breaker of the present embodiment has a structure in which a first side case 1A (cover) made of synthetic resin on both sides and a second side case 1B (body) are connected to each other. Two fixed contacts 2A and 2B arranged side by side in the width direction, two movable contacts 4A and 4B fixed to the fixed contacts 2A and 2B, and movable contacts 3A and 3B facing each other so as to be freely separated, and Two movable contacts 4A, 4
With the opening / closing mechanism 5 for driving B, the handle 6 is inserted.
Each movable contact 3A, 3 via the opening / closing mechanism 5 by the opening operation
B is configured to contact (separate / separate) from each fixed contact 2A, 2B, and each fixed contact 2A, 2B and each movable contact 4A, 4B are vertically moved in the height direction of the body 1. Of the two movable contacts 4A, 4B, one movable contact 4B interposed between the two fixed contacts 2A, 2B in the height direction and the movable contact 3A of the other movable contact 4A contact and separate from each other. The fixed contact 2A is disposed at a height position where the movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B and do not intersect when viewed in the width direction of the body 1. In addition, the first contact portion composed of the fixed contact 2A and the movable contact 3A is inserted into the voltage pole of the main circuit, and the second contact portion composed of the fixed contact 2B and the movable contact 3B is connected to the ground electrode (neutral pole) of the main circuit. Inserting.

Inside the one end of the body 1, both side cases 1A, 1
The intermediate case 7 molded from a synthetic resin material is fixed so as to be sandwiched between B and is constituted by a recess 8 inside the side wall (outer wall) of the second side case 1B and a vertical wall portion 35 of the intermediate case 7. The terminal block 10B forming the ground electrode side electric path having the fixed contact 2B at one end is housed in the compartment to be formed, and the recess 9 provided on the first side case 1A side of the intermediate case 7 and the side wall of the first side case 1A. A terminal block 10A constituting a voltage pole side electric circuit having a fixed contact 2A at one end is housed in a compartment defined by (outer wall).

In the terminal block 10A, a terminal plate 11 bent in a U shape and an extension piece 11a are integrally extended above one end of a central piece of the terminal plate 11, and the extension piece 11a is extended from the upper end to the extension piece 11a. Bend at a right angle to the terminal plate 1
Fixed contactor 12A integrally extended outward with respect to 1
A fixed contact 2A that is caulked and fixed to the upper surface of one end of the fixed contactor 12A, and a substantially M-shaped locking spring 13A that is placed on the lower piece of the terminal plate 11 and is housed in the terminal plate 11. Composed. This terminal block 10A constitutes the bottom portion of the recess 9 of the intermediate case 7, and the lower piece of the terminal plate 11 is placed on the lateral wall portion 24 that extends parallel to the bottom portion of the body 1, and one end portion of the recess 9 is placed vertically. The extension piece 11a is arranged along the wall 25 so as to extend beyond the upper end of the vertical wall 25 to guide the fixed contactor 12A to the outside of the recessed portion 9 and to extend outside the recessed portion 9 in the longitudinal direction of the second side case 1B. By disposing the tip of the fixed contactor 12A on the lateral wall 15 that is integrally formed substantially parallel to the bottom of the two-side case 1B, the fixed contactor 12A is disposed in the recess 9. The lateral wall 15 is formed with a recess 15a that allows the lower end of the fixed contact 2A protruding to the lower surface side of the fixed contact 12A to escape. Terminal board 11
Has a T-shaped piece 11b integrally extending upward from the other end of the upper piece, and the tip of the lateral protrusion of the upper end of the T-shaped piece 11b is formed on the wall surface of the intermediate case 7 as a convex flat portion. 22 'is mounted on the upper end surface. Further, on the side surface of the side piece of the terminal plate 11, there is integrally formed a protrusion 23 which is inserted into the pressing piece 13b of the locking spring 13A and prevents rattling of the locking spring 13A.

The lock spring 13A and the terminal plate 11 constitute a so-called quick-connect terminal, and the first case 1A and the intermediate case 7 are connected to each other.
When overlapping, the diagonal downward groove 160 having a semicircular cross section provided in the vertical wall portion at the other end of the concave portion 9 of the intermediate case 7 and the other end of the first side case 1A like the diagonal downward groove 160. The core wire of the electric wire (not shown) inserted from the outside through the electric wire insertion hole 16A formed by the oblique downward groove 160 provided on the vertical wall of the portion is the upper piece of the terminal plate 11 and the locking spring 13.
It is press-fitted between the upper end of the locking piece 13a of A and the upper end of the pressing piece 13b. The tip of the locking piece 13a locks the core wire in the direction of pulling out the electric wire, and The core wire is electrically connected and mechanically held by being pressed against the upper piece of the terminal plate 11. This electric wire lock is released by a release handle 17, and the release handle 17 has a rotating shaft 18 provided on the lower side surface thereof rotatable in a shaft hole 20 provided on a convex flat portion 22 ′ on the inner side surface of the intermediate case 7. An operating portion which is rotatably supported in a concave portion 37 formed on a side surface of the shaft 38 and which is rotatably supported on the inner wall surface of the first side case 1A and is exposed to the outside of the body 1. By manually manipulating and rotating 17a, the driving projection 19 provided at the lower end causes the locking piece 13 of the locking spring 13A to move.
It is possible to release the locked state with respect to the core wire by pushing the tip of one end of a to bend the locking piece 13a. Reference numeral 21 in the drawing denotes a return spring that constantly biases the release handle 17 in the anti-manual operation direction.

On the other hand, the terminal block 10B is basically the same as the terminal block 10A and has a terminal plate 11 and a locking spring 13B.
And the fixed contactor 12B, the terminal block 10 is different from the terminal plate 11 of the terminal block 10A.
The terminal plate 11 of B is an extension piece 1 extending downward from one end of the lower piece.
1c is formed by extension, and the body 1 is formed from the tip of the extension piece 11c.
The fixed contact 12B is formed to extend in parallel with the bottom of the terminal plate 11 and the back piece 11d is formed to extend at a right angle from one end of the side piece of the terminal plate 11.

The lock spring 13B has the same structure as the lock spring 13A, and is placed on the lower piece of the terminal plate 11,
The protrusion 23 protruding from the side piece of the terminal board 11 is the pressing piece 1.
It is designed to be inserted into 3b.

This terminal block 10B is the second side case 1
The lower piece of the terminal plate 11 is placed on the downwardly inclined bottom surface of the concave portion 8 of B, and the back piece 11d is arranged along the rising wall 8a at one end of the concave portion 8, and the lower end of the rising wall 8a and the bottom surface of the concave portion 8 are formed. The terminal board 1 is provided in the notch 27 formed between the terminal board 1 and the one end side.
The extension piece 11c is fitted to the outside of the recess 8 by fitting one end of the first case 1, and when the intermediate case 7 is superposed on the second side case 1B side, the tip of the fixed contactor 12B, that is, the fixed contact 2B. The lower surface provided is the rib 2 at the bottom of the second side case 1B.
6 is to be placed on. A partition wall 14 is provided upright from the bottom of the second side case 1B in the vicinity of the tip of the fixed contact 12B, and a recess between the partition wall 14 and the rib 26 is formed at the tip of the fixed contact 12B. The bottom end of the fixed contact 12B of the fixed contact 2B that has been caulked and fixed and that protrudes to the lower surface side is a relief.

Further, the tip of the lateral projecting portion at the upper end of the T-shaped piece 11b extended above the other end of the upper piece of the terminal plate 11 has a convex flat portion formed on the wall surface of the second side case 1B. It is placed on the upper end surface of 22.

The locking spring 13B and the terminal plate 11 of the terminal block 10B form a quick-connect terminal as in the case of the terminal block 10A, and when the intermediate case 7 is superposed on the second side case 1B, the second side An oblique downward groove 160 having a semicircular cross section provided on the vertical wall portion at the other end of the recess 8 of the case 1B, and an oblique downward groove 160 provided on the opposing wall surface of the intermediate case 7 like the oblique downward groove 160. When an electric wire is inserted through the electric wire insertion hole 16B formed by
The locking piece 13a of 3B locks the core wire, and the pressing piece 13b presses the core wire against the upper piece of the terminal plate 11 to electrically connect the electric wire and mechanically lock the wire.

The release handle 17 'is used to release the electric wire lock. The release handle 17' has a rotary shaft 18 provided on the lower side surface thereof like the release handle 17 and has a convex flat surface on the second side case 1B. A shaft (not shown) that is rotatably supported in the shaft hole 20 provided in the portion 22 and is projected to the wall surface of the vertical wall portion 35 of the intermediate case 7 is rotated in the recess 37 provided on the other side surface of the lower portion. By manually operating and rotating the operation portion 17a that is freely pivotally supported and is exposed to the outside of the body 1, the drive protrusion 19 provided at the lower end is provided on one side of the locking piece 13a of the locking spring 13B. The locking piece 13a can be bent by pushing the tip of the end to release the locking of the core wire. 2 in the figure
Reference numeral 1'denotes a return spring for constantly biasing the release handle 17 'in the anti-manual operation direction.

The open / close mechanism 5 for driving the movable contacts 4A, 4B to open and close is a handle 6, a connecting member 43 for connecting the handle 6 to the movable contact 4A on the voltage electrode side, and the movable contact 4A.
It comprises a latch plate 58 having a protruding latch portion 60 for locking (latching) the rear end portion, a driving member 40 and the like.

The connecting member 43 includes a contact pressure spring 44 formed of a torsion coil spring and bent at both ends at substantially right angles to form shafts 44a and 44b, and a guide plate 45 formed of a metal plate in a substantially trapezoidal shape. The shafts 44 of the contact pressure springs 44 are attached to the guide holes 45a and 45b which are provided at both ends of the lower bottom of the plate 45.
a and 44b are penetrated. In addition, one shaft 44a
A guide hole 45a through which (hereinafter, referred to as "upper shaft") penetrates
Is a round hole, and the guide hole 45b through which the other shaft 44b (hereinafter referred to as "lower shaft") penetrates is a long hole in which the axial direction of the long axis is substantially aligned with the lower bottom of the guide plate 45.

The handle 6 is composed of an operating portion 6a, a rotating portion 6b, and a handle shaft 6c. The handle shaft 6c protruding in the center of both side surfaces of the rotating portion 6b is formed on the inner surface of the first side case 1A. Rotatably inserted into the shaft hole 49 and the shaft hole 49 formed in the inner surface of the second side case 1B, and is pivotally supported between the side cases 1A and 1B. Body 1 configured by connecting 1A and 1B
The window 50 is opened on the upper surface of the. A handle urging spring 51, which is a torsion coil spring, is attached to the handle shaft 6c, and the handle urging spring 51 urges the handle 6 in the opening (off) direction at the closing (on) position (see FIG. 5). It is energized.

The upper shaft 44a of the contact pressure spring 44 penetrating the guide hole 45a of the guide plate 45 is rotatably inserted into a shaft hole (not shown) provided at the lower end of the rotating portion 6b, and the handle 6 Are connected to the connecting member 43.

The connecting member 43 has a lower shaft 44b of a contact spring 44 which penetrates through the guide holes 45b of the guide plate 45 into bearing holes 30 provided on both sides of the movable contactor 4A in the substantially longitudinal center thereof.
Is rotatably inserted and connected to the movable contactor 4A, and is arranged in the body 1 so as to be vertically movable.

The driving member 40 is formed of an insulating synthetic resin into a substantially rectangular flat plate shape, and the longitudinal direction is aligned with the vertical direction (height direction) of the body 1 in the vertical direction between the two side cases 1A and 1B. It is sandwiched so as to be slidable, and a cut groove 40a for laterally fitting the side portion of the movable contactor 4A is formed on the upper side portion of the first case 1A side, and a lower second side case 1B side portion. The side portions are provided with cut grooves 40b into which the movable contacts 4B are laterally fitted. Further, a substantially cylindrical fixing portion 40c is projectingly provided at an end portion of the lower surface of the driving member 40 on the side of the first side case 1A, and an upper end portion of an opening spring 53 composed of a compression coil spring is externally fitted to the fixing portion 40c. And then fixed. Further, a rib 111a is provided from the inner surface of the second side case 1B along the standing wall 31 and the separating wall 14 between the standing wall 31 and the separating wall 14 which are erected from the bottom of the second side case 1B substantially parallel to the separating wall 14. The lower end of the opening spring 53 is inserted and fixed in a recess (which is referred to as a "fixed recess") 111 that is formed and is surrounded by the standing wall 31, the isolation wall 14, and the rib 111a. Therefore, the drive member 40 is arranged inside the body 1 in a state in which the opening spring 53 is compressed, and is biased upward by the spring force of the opening spring 53. At this time, since both ends of the opening spring 53 are fixed to the fixing portion 40c provided on the drive member 40 and the fixing recess 111 provided on the second side case 1B, respectively, buckling of the opening spring 53 is prevented. Therefore, the drive member 40 can be surely biased.

Further, a step portion 56a of a substantially hook-shaped rib 56 projecting from the inner surface of the first side case 1A and a recess formed below the cut groove 40a on the side portion of the drive member 40 on the side of the first side case 1A. 40d and the upper step portion 33a of the vertical wall 33 extending in the vertical direction from the end surface of the lateral wall 15 projecting from the inner surface of the second side case 1B, which is opposite to the recessed portion 8 of the lateral wall 15. An outer flange portion 40e formed between the recess 40d of the drive member 40 and the cut groove 40b is in contact with and separable from each other, and further, the restriction rib 62 projecting from the inner surface of the second side case 1B and the drive member 40. The movable range of the drive member 40 is regulated by the contact with the upper end of the drive member so that the drive member 40 can move freely. Further, guide recesses 34 for guiding the outer flange portion 40e projecting in the width direction of the body 1 are provided on the inner surfaces of the both side cases 1A and 1B in the movement range of the drive member 40.

Here, the movable contactor 4A is composed of a rigid conductive metal plate, is inserted into the cut groove 40a of the driving member 40 from the side, and the movable contact 3A fixed by caulking to the tip is fixed to the corresponding fixed contact 2A. In addition to being separated and contacted, it moves up and down in the body 1 in conjunction with the vertical movement of the connecting member 43,
The driving member 40 is slid in the vertical direction by pressing the opening edge of the cut groove 40a. Here, since the movable contactor 4A is made of a rigid body, it hardly bends in the thickness direction along the moving direction thereof.

The movable contactor 4B is made of a conductive thin plate material having elasticity, is inserted into the cut groove 40b of the driving member 40 from the side, and is pushed downward when the driving member 40 moves downward to bend. From this bent state, the movable contact 4
When the latched state of A is released and the upward movement of the driving member 40 is no longer regulated, the driving member 40 returns to its original state.
It is designed to come into contact with and separate from.

As shown in FIGS. 1 and 2, the overcurrent trip device 47 includes an electromagnetic drive unit 48 for driving the latch plate 58 when an excessive current such as a short circuit current flows, and an overload current such as an overload current. The latch plate 58 is bent and displaced when an overcurrent flows.
And a bimetal 46 that drives the. The electromagnetic drive unit 48 includes a first iron core 57 formed by bending a magnetic iron plate into a substantially U-shape in a plan view, a second iron core also serving as a latch plate 58, and a second iron core (latch member) 58 of the first iron core 57. The first magnetic core 57 is swingably opposed to and supported by the magnetic pole surfaces on both ends, and the first iron core 57 is attached to the second iron core 5.
The second iron core 58 while being elastically biased away from
Spring 5 for elastically urging the elastic member away from the first iron core 57
9 and 9.

The second iron core (latch member) 58 is made of a metal material (magnetic iron plate) harder than the metal material (copper alloy) forming the movable contact 4A, and has a rectangular main portion 58a and a main portion 5.
Mounting piece 58b projecting from the center of the lower edge of 8a and stopper piece 58c projecting from the center of the upper edge of the main portion 58a.
And a latch portion 60 having a substantially triangular side surface projecting from the center of the surface of the main portion 58a opposite to the surface facing the first iron core 57.
And a caulking pin (not shown) inserted through a mounting hole 58d penetrating the mounting piece 58b and a central piece 59 of the leaf spring 59.
By being inserted into a hole 59b formed in the central portion of a and caulking, the plate spring 59 is swingably supported.

On the other hand, the leaf spring 59 is inserted into a hole 59e penetrating the lower end portion of the central piece 59a, and a caulking pin 67 is inserted into a hole 46a formed in the lower end portion of the bimetal 46 to caulk the bimetal 46. The piece 59a is erected from the lower end. Further, both side pieces 59c bent and formed on both sides of the upper end of the central piece 59a of the leaf spring 59 are attached to the first iron core 57.
Locking pieces 59d that are arranged along the outer surfaces of the both side pieces 57a and project inwardly at the tips of the both side pieces 59c are locked in the recesses 57b formed in the outer corner portions of the first iron core 57. As a result, as shown in FIG.
The bimetal 46 which is erected from the lower end of the 9a is attached to the first iron core 5
The leaf spring 59 is fixed to the first iron core 57 by being interposed between the second iron core 7 and the second iron core (latch member) 58. At this time, the magnetic pole surfaces, which are the tips of the both side pieces 57a of the first iron core 57, have the leaf springs 59.
Is opposed to the second iron core (latch member) 58 via the center piece 59a and the both side pieces 59c, and the lower end portions of the magnetic pole surfaces of the both side pieces 57a are in contact with the second iron core 58 in the open state. ,
The upper end of the magnetic pole surface is separated from the second iron core 58. The leaf spring 59 also includes a first spring portion 59 </ b> A (first leaf spring) that connects the bimetal 46 and the second iron core 58, and a second spring portion 59 that connects the second iron core 58 and the first iron core 57. Spring part 59
B (second leaf spring) and two spring portions,
The spring constant of the first spring portion 59A is made larger than the spring constant of the second spring portion 59B by changing the width dimension and the length dimension of both spring portions. As described above, since the first iron core 57, the second iron core 58, and the bimetal 46 are connected to each other via the leaf spring 59, the first iron core 57, the second iron core 58, and the bimetal 46 should be treated as one component. And the assembling work becomes easy. Further, since the first spring portion 59A and the second spring portion 59B are continuously and integrally formed from one piece of spring material, the number of parts is reduced, and product quality control and storage are facilitated.

One end of the bimetal 46 is the movable contactor 4A.
The other end of the braided wire 79 welded to is welded to the plate surface slightly below the center, and the fixed contact 2A and the movable contact 3
A conductive plate 70 forming a voltage pole side electric path electrically connected to the contact portion made of A is joined to the plate surface at the upper end. The conductive plate 70 made of a metal plate includes an inverted L-shaped main piece 70a and an L-shaped extending piece 70b extending from an upper end of the main piece 70a.
And a joining piece 70c extending from the tip of the extending piece 70b in parallel with the main piece 70a, and an L-shaped fixing piece 70d extending from the lower end of the main piece 70a. The bimetal 46 is joined to the intermediate portion and the fixing piece 7
A blade receiving spring portion 78 sandwiching a conductive bar (not shown) of a voltage electrode disposed in the distribution board is welded and fixed to the lower end of 0d, and the blade receiving spring portion 78, conductive plate 70, bimetal 46, and braid Line 7
9 and the movable contactor 4A are electrically connected.

Thus, when an excessive current such as a short circuit current flows through the terminal block 10A and the conductive plate 70 to the bimetal 46 inserted in the electric path of the voltage pole, the first iron core 57 is formed.
Is excited and the magnetic force generated on the magnetic pole surfaces at the tips of both side pieces 57a and 57a of the first iron core 57 resists the urging force of the first spring portion 59A and the second spring portion 59B of the leaf spring 59 to cause the second iron core ( The latch plate) 58 is sucked and swung to move the movable contactor 4A.
The latch portion 60 that latches the rear end portion is moved. By thus providing the second iron core 58 with the latch portion 60 and also serving as the latch member, the number of parts is reduced and the work of incorporating the overcurrent trip device 47 into the body 1 is simplified.

When an overload current flows through the load, the bimetal 46 heats up and bends due to the overload current, and the lower end of the bimetal 46 is displaced so as to move leftward in FIG. The latch member (second iron core) 58 connected to the second side case 1B via a leaf spring 59.
Stopper piece 58 that contacts the contact piece 106 provided on the inner side surface
Rotate clockwise with c as a fulcrum. As a result, the latch portion 60 provided on the latch member (second iron core) 58 is moved leftward, the latched state of the rear end portion of the movable contactor 4A is released, and the contact portion is forcibly opened.

On the other hand, in the movable contactor 4B on the ground electrode side, a conductive plate 71 forming an electric path on the ground electrode side is welded to the rear end portion.
As shown in FIG. 3, the conductive plate 71 made of a metal plate has a main piece 71a to which the movable contact 4B is welded at one end and a main piece 71.
The standing piece 71b rising from the other end of a and the standing piece 71b.
and an L-shaped extension piece 71c extending from the tip of b, the tip of the extension piece 71c has a ground electrode disposed in the distribution board in the same manner as the blade receiving spring portion 78 described above. A blade receiving spring portion 81 sandwiching a conductive bar (not shown) is fixed by welding, and the blade receiving spring portion 81, the conductive plate 71, and the movable contactor 4B are electrically connected.

In assembling the circuit breaker of this embodiment, first, the terminal block 10B is housed in the recess 8 of the second side case 1B and the release handle 17 'is provided.
Is assembled in place with the return spring 21 '. Further, the handle 6 is assembled at a predetermined position together with the handle biasing spring 51, and further, the blade receiving spring portion 81 is stored in the upper blade receiving spring portion storage portion 93 provided above one end portion, and the standing piece 71b of the conductive plate 71 is fixed. The second side case 1B is arranged along the gap between the partition walls 91 and 92. Further, an obliquely upwardly inclined portion of the central portion of the movable contactor 4B is parallel to the bottom of the second side case 1B from the lower end of the partition wall 92 located slightly above the bottom of the second side case 1B. Further, the movable contactor 4B is arranged between the partition wall 95 which is inclined upward from the parallel portion and extends upward and the bottom portion of the second side case 1B, and the free end side of the movable contactor 4B is fixed across the standing wall 31 and the isolation wall 14. Contact 12B
It is arranged in the space where is arranged. At this time, the main piece 71a of the conductive plate 71 and the rear end of the movable contactor 4B are sandwiched and fixed by a plurality of ribs 96 protruding from the bottom surface of the parallel portion of the partition wall 95 and the bottom portion of the second side case 1B.

The movable contact 4B is sandwiched in the cut groove 40b of the driving member 40, and both ends of the opening spring 53 are fixed to the fixing portion 40c on the lower surface of the driving member 40 and the fixing concave portion 111 provided at the bottom of the second side case 1B. The drive member 40 is fixed and disposed in a compressed state between the drive member 40 and the bottom of the second side case 1B, and the drive member 40 is disposed at a predetermined position of the second side case 1B so as to be slidable in the vertical direction. Also, the second side case 1B
The blade receiving spring portion 78 is stored in the blade receiving spring portion storage portion 90 located below the upper blade receiving spring portion storage portion 93, and the locking groove 99 is provided above the partition wall 92 on the inner surface of the second side case 1B. The upper end of the main piece 70a of the conductive plate 70 is fitted into the fitting groove 94, and the extension piece 70b of the conductive plate 70 is fitted into the fitting recess 94 provided in the inner surface of the second case 1B above the locking groove 99. The conductive plate 70 is housed and fixed in the second side case 1B, and the bimetal 46 is fixed to the fixing piece 70d of the conductive plate 70 in a space closer to the center than the partition wall 92 along the longitudinal direction of the second side case 1B. The current trip device 47 is housed. The tip of the stopper piece 58c of the second iron core (latch member) 58 is brought into contact with the contact piece 106 projecting from the inner side surface of the second side case 1B so as to face the joint piece 70c of the conductive plate 71, whereby the second piece is formed. The movement of the iron core (latch member) 58 is restricted.

Further, a portion between the central portion where the bearing hole 30 of the movable contactor 4A connected to the bimetal 46 by the braided wire 79 is provided and the tip end portion where the movable contact 3A is fixed is formed in the cut groove of the driving member 40. Lower shaft of the contact pressure spring 44 inserted into the guide hole 45b of the guide plate 45 while inserting the upper shaft 44a of the contact pressure spring 44 inserted into the guide hole 45a of the guide plate 45 into the shaft hole of the handle 6 44b is inserted into the bearing hole 30 of the movable contactor 4A, and the connecting member 43 is inserted.
Is connected to the handle 6 and the movable contactor 4A. At this time, the tip end portion of the lower shaft 44b penetrating the bearing hole 30 of the movable contactor 4A is fitted into the guide groove 103 provided vertically below the shaft hole 49 on the inner surface of the second side case 1B. The lower shaft 44b is guided by the guide groove 103 as the connecting member 43 moves up and down. Further, a positioning projection 105 protruding upward is formed in the vicinity of the lower end of the guide groove 103 of the partition wall 95 provided in the second side case 1B in the width direction of the second side case 1B, and the handle 6 is operated to the closing position. The connecting member 43 is positioned by bringing the projecting piece 45c provided in the vicinity of the lower guide hole 45b of the guide plate 45 into contact with the positioning projection 105 with the connecting member 43 moving downward and closing the contact portion ( (See FIG. 5).

In this way, the intermediate case 7 and the terminal block 10A housed in the recess 9 of the intermediate case 7, the release handle 17 and the return spring 21 other than the terminal block 10A are laterally fitted to the second side case 1B. After that, the intermediate case 7 in which the terminal block 10A, the release handle 17 and the return spring 21 are assembled in the recess 9 is arranged so as to overlap with the second side case 1B side.

When the intermediate case 7 is arranged at a fixed position on the first side case 1A side, the tip side of the fixed contact 12A provided on the terminal block 10A is recessed into the recess 15a of the lateral wall 15.
The shaft (not shown) is fitted on the recess 37 of the release handle 17 '.

In this state, the first side case 1A is superposed on the second side case 1B side and connected. At this time,
Two elastic locking pieces 100 are integrally projectingly provided toward the first side case 1A side from both ends in the up-down direction and the left-right direction on the inner surface of the second side case 1B. A claw-shaped hooking portion 101 at the tip of 100 is locked to a projection-shaped hooked portion 102 provided corresponding to the first side case 1A side to connect and fix the first side case 1A and the second side case 1B. As a result, the body 1 is constructed. When disconnecting and fixing the first side case 1A and the second side case 1B,
A driver is inserted through a release hole (not shown) opened corresponding to each hooked portion 102 in the first side case 1A, and the hooking portion 101 of the corresponding elastic locking piece 100 is pressed (suppressed) in the unlocking direction. Then, the first side case 1A can be removed from the second side case 1B by removing the hooked state with the hooked portion 102.

Here, a rectangular plate-shaped rib 110 projecting toward the second side case 1B is formed on the inner side surface of the first side case 1A above the bottom in the approximate center in the longitudinal direction. When the body 1 is assembled by connecting the case 1A and the second side case 1B, the braided wire 79 is sandwiched between the tip end surface of the rib 110 and the inner side surface of the second side case 1B.
With 0, the braided wire 79 can be positioned on one side in the width direction of the bimetal 46 substantially orthogonal to the displacement direction of the bimetal 46 (longitudinal direction of the body 1). Therefore, the braided wire 79 does not get in the way when the bimetal 46 described later is displaced,
The displacement characteristic of the bimetal 46 is less affected by the braided wire 79.

Now, the blade receiving spring portion 78 for vertically sandwiching the conductive bar is formed inside one longitudinal end of the body 1 constructed by connecting the first and second side cases 1A and 1B as described above. , 81 are stored and arranged, and these blade receiving spring portions 78,
Corresponding to No. 81, one end of the body 1 is provided with a conductive bar insertion groove 107 having a U-shaped opening on the end surface and both side surfaces of the body 1,
108 will be formed.

A pair of electric wire insertion holes 16A, 16B are formed in parallel with each other in the longitudinal direction of the body 1 so as to open obliquely upward. Then, the load side electric wires are respectively inserted into the electric wire insertion holes 16A and 16B and connected to the respective terminal blocks 10A and 10B, and the conductive bars are connected to the respective blade receiving spring portions 78 and 81, so that the electric path of the present embodiment can be realized. It will be possible to insert a circuit breaker.

Here, as shown in FIG. 4, a first contact portion composed of the fixed contact 2A and the movable contact 3A and a second contact portion composed of the fixed contact 2B and the movable contact 3B are arranged side by side in the height direction of the body 1. By doing so, the body 1 can be downsized in the width direction. In addition, the first contact portion is arranged substantially in the center of the body 1 in the width direction, and the second contact portion is arranged at one end portion (the end portion on the second side case 1B side) of the body 1 in the width direction. The other end portion in the width direction of 1 (first side case 1A
By disposing the opening spring 53 at the side end portion, the load applied to the first and second contact portions can be stabilized. Further, the first contact portion and the second contact portion are isolated by the horizontal wall 15 provided on the second side case 1B, the vertical wall 33, and the driving member 40 arranged in parallel with the vertical wall 33, and the first contact portion and the second contact portion are sufficiently separated from each other. Insulation distance can be secured.

Next, the operation of this embodiment will be described with reference to FIGS.

FIG. 4 shows a contact opening (OFF) state. In this contact opening state, the operating portion 6a of the handle 6 is exposed upside down through the window hole 50, and the movable contactor 4A and the rear end thereof are latched. The latch portion 60 of the plate 58 is in a latched state. The drive member 40 is biased upward (upward in the height direction, the same applies below) in the drawing of the body 1 by the opening spring 53, and the movable contactor is inserted into the cut groove 40a of the drive member 40. 4A has its free end moved upward, and the movable contact 4B inserted into the cut groove 40b has its free end moved upward by its spring elastic force. Movable contacts 3A, 3B provided
Is in a state of being separated from the corresponding fixed contacts 2A and 2B (opening state).

When the operating portion 6a of the handle 6 is rotated counterclockwise in this figure in this state, the upper shaft 44a of the contact pressure spring 44 is pushed downward as shown in FIG.
The movable member 4A is rotated clockwise with the rear end of the connecting member 43 latched by the lower shaft 44b of the contact pressure spring 44 by the latch portion 60 as a fulcrum, and the movable contact 3A at the free end becomes the fixed contact 2A. Bring them closer. Further, the rotation of the movable contactor 4A drives the driving member 40 having the movable contactor 4A inserted into the cut groove 40a to move downward, and this movement causes the movable member 4A to be moved into the cut groove 40b of the drive member 40 to move. The contactor 4B is bent in the direction of moving the free end downward, and the movable contact 3B at the free end is brought into contact with the fixed contact 2B. Here, the distance traveled by the movable contact 3B until it comes into contact with the fixed contact 2B (the distance between the contacts of the second contact in the open state) is
Since the movable contact 3A is shorter than the distance (the distance between the contacts of the first contact portion) that the movable contact 3A moves before coming into contact with the fixed contact 2A, the movable contact 3B that has a shorter moving distance to the contact comes first with the fixed contact 2B. Upon contact, the second contact part is closed.

When the operating portion 6a of the handle 6 is further rotated counterclockwise, the movable contactor 4A is rotated clockwise while the flexible movable contactor 4B is further bent, and the movable contactor 3A is moved. To contact the fixed contact 2A
Close the contact. When the operating portion 6a of the handle 6 is further rotated counterclockwise from there, a contact pressure is applied from a line connecting the position of the lower shaft 44b of the contact spring 44 and the rotation center of the handle 6, as shown in FIG. The upper shaft 44a of the spring 44 moves to the right in the figure, and in this state, the handle biasing spring 51 that biases the handle 6 clockwise, the opening spring 53 that biases the drive member 40 upward, and the movable contactor. 4A is urged downward, and the spring force of the movable contactor 4B is balanced to maintain the latched state between the rear end of the movable contactor 4A and the latch portion 60 of the latch plate 58. The closed state (ON state) of No. 5 is maintained.

In this closed state, a downward force is exerted on the movable contactor 4A by the spring force (restoring force) of the contact pressure spring 44, and this force causes the movable contact 3A and the fixed contact 2A to move.
In addition to obtaining the contact pressure of, the downward force also acts on the movable contactor 4B via the driving member 40 that is driven downward on the movable contactor 4A, and this force causes the contact pressure between the movable contact point 3B and the fixed contact point 2B. It has gained. That is, in this embodiment, a contact pressure (contact pressure) can be applied to the first and second contact portions when the contact is closed by the contact pressure spring 44 formed of a torsion coil spring, and a separate spring for applying contact pressure needs to be provided. Therefore, the number of parts can be reduced, and the assembling work into the body 1 can be simplified. In the closed state, the guide plate 45
A protruding piece 45c provided on the lower part of the contact spring 44 contacts the positioning protrusion 105 of the body 1 and the lower shaft 44b of the contact pressure spring 44 is attached to the body 1;
Since it is guided by the guide groove 103 provided in the movable contact 3, the movement of the lower shaft 44b of the contact pressure spring 44 is restricted.
A and 3B and fixed contacts 2A and 2B can be easily brought into contact with each other accurately.

When the operating portion 6a of the handle 6 is rotated clockwise in the closed state, the upper shaft 44a of the contact pressure spring 44 is rotated.
When the position exceeds the line connecting the center of rotation of the handle 6 and the position of the lower shaft 44b of the contact spring 44 to the left, the balance of the spring force and the like is lost, and the connecting member 43 causes the contact spring to move. 44
The handle 6 is moved upward by the urging force and the handle 6 is rapidly returned to the open (OFF) side by the urging force of the handle urging spring 51. By the upward movement of the driving member 40, the movable contactor 4A is rotated counterclockwise with the rear end portion latched by the latch portion 60 as a fulcrum, and the free end is moved upward to move the movable contact 3A from the fixed contact 2A. The contacts are opened to open the first contact portion. Further, since the movable contactor 4A is rotated counterclockwise to drive the driving member 40 and move upward, there is no force to push the movable contactor 4B downward, and the spring force restores the original state. The movable contact 3B at the free end is separated from the fixed contact 2B to open the second contact portion. Here, as described above, the distance between the contacts of the second contact portion is made shorter than the distance between the contacts of the first contact portion, and the movable contactor 4B is formed of a flexible spring material. The movable contact 3A separates from the fixed contact 2A before the bent movable contactor 4B returns to the original state to separate the movable contact 3B from the fixed contact 2B, and then returns to the original state. The child 4B moves the movable contact 3B upward to separate the movable contact 3B from the fixed contact 2B (see FIG. 4).

By the way, in the closed state shown in FIG. 5, when an excessive current such as a short circuit current flows, the first iron core 57 of the electromagnetic drive unit 48 constituting the overcurrent trip device 47 is formed.
The second iron core (latch member) 58 corresponding to the magnetic force generated in the
Is suction-oscillated against the spring biasing force of the first and second spring portions 59A and 59B. Here, since the spring constant of the first spring portion 59A is set to a value larger than the spring constant of the second spring portion 59B, when a suction force is generated between the first iron core 57 and the second iron core 58, First, only the second spring portion 59B is bent, and the first iron core 57 rotates clockwise in the drawing around the lower end of the tip end surface (magnetic pole surface) of the both side pieces 57a, so that the tip end surface (the magnetic pole piece 57a The upper end of the surface moves toward the second iron core 58. When the second spring portion 59B bends to a predetermined position, the upper end portion of the magnetic pole surface of the first iron core 57 protrudes from the inner surface of the second side case 1B as shown in FIG. The upper end of the magnetic pole surface of the first iron core 57 is prevented from further displacing in the right direction in the figure (direction toward the second iron core 58).

When the upper end of the magnetic pole surface of the first iron core 57 comes into contact with the restricting rib 109 to restrict the movement of the first iron core 57, the suction generated between the first iron core 57 and the second iron core 58. When the force becomes larger than the urging force of the first spring portion 59A, the first spring portion 59A begins to bend and the first spring portion 59A
The second iron core 58 rotates counterclockwise in the figure with the connecting portion of A and the bimetal 46 as a fulcrum, whereby the latch portion 60 provided on the second iron core (latch member) 58 moves leftward as shown in FIG. Then, the latched state of the rear end of the movable contactor 4A is released. When the latched state of the rear end of the movable contactor 4A is released, the driving member 40 moves upward due to the biasing force of the opening spring 53, so that the movable contactor 4A supports the lower shaft 44b of the contact pressure spring 44 as a fulcrum. As the movable contact 4B is rotated counterclockwise, the movable contact 4B is restored to its original state without being pushed down by the drive member 40, and the movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B, respectively. The second contact part is forcibly opened. At this time, the movable contact 3A is fixed before the movable contact 4B, which is bent in the closed state, is returned to its original state and the movable contact 3B is separated from the fixed contact 2B as in the opening operation described above. To separate from 2A,
Even during the tripping operation due to the short-circuit current, the first contact portion of the voltage electrode is opened before the second contact portion of the ground electrode (see FIG. 6).

After that, when the magnetic force ceases to be generated in the first iron core 57 of the electromagnetic drive unit 48 due to the interruption of the electric path, the second iron core (latch member) 58 returns to its original state by the spring force of the leaf spring 59. Further, since the balance of the spring force and the like is lost by releasing the latched state of the rear end portion of the movable contactor 4A, the handle 6 is rapidly rotated to the opening (OFF) side by the urging force of the handle urging spring 51. Upon returning, the connecting member 43 moves upward.

FIG. 9 shows the relationship between the magnetic gap between the two iron cores 57 and 58 during the tripping operation due to an overcurrent such as a short circuit current and the load during the operation.
From 1), the upper end of the magnetic pole surface of the first iron core 57 is the regulating rib 10
9 to the position (P2) where the second spring portion 59 contacts.
Only B is bent, and the magnetic gap changes from G0 to G1, and the spring load generated during this period becomes the spring load of the second spring portion 59A. Further, from the position (P2, P3) where the upper end of the magnetic pole surface of the first iron core 57 abuts against the regulation rib 109 to the trip position (P4), the first spring portion 59A is bent and the magnetic gap is reduced. The spring load changed from G1 to G2, and the spring load during that time was the spring load of the first spring portion 59A plus the force necessary to pull the latch portion 60 out (friction force between the latch portion 60 and the movable contact 4A). It becomes a load.

Here, the operating characteristics of the overcurrent trip device 47 will be described with reference to FIGS. Figure 8 (a)
Shows the current waveforms of various currents flowing in the energization path, a in the figure is the waveform of the motor starting current that flows when the motor is started when the motor is connected to the load, and b is the half that is applied when conducting the overcurrent test. Wave current waveform, C is a half-wave current waveform applied when performing a cord short-circuit test, and D is a half-wave current waveform applied when performing a short-circuit test. Also, FIG.
8B shows the displacement of the first iron core 57 and the second iron core 58 when the motor starting current is applied, and FIGS.
(E) is an overcurrent test, a cord short-circuit test,
The displacement of the 1st iron core 57 and the 2nd iron core 58 at the time of performing a short circuit test is shown. 8B to 8E, the dotted line indicates the displacement of the first iron core 57, and the solid line indicates the displacement of the second iron core 58, respectively. The second iron core 58 is displaced toward the first iron core 57 side, and The latched state by the latch portion 60 is released when the interval becomes a predetermined interval.

In the present embodiment, when a large current flows in the energizing path, first, the second spring portion 59B bends to move the first iron core 57 to the second iron core 58 side to a predetermined position, and then the first spring portion 59B. Since 59A bends to bring the second iron core 58 close to the first iron core 57 side to release the latch, a motor starting current (a in FIG. 8A) flows when the motor is started. In this case, the first iron core 57 moves toward the second iron core 58, but before the second iron core 58 moves toward the first iron core 57 because the motor starting current flows for a short period of time. Even when the motor starting current stops flowing, and therefore the motor starting current having a larger current value than the operating current I2 of the second iron core flows, the latched state by the latch unit 60 is not released and the contact portion is forcibly forced. It will not be opened.

In the case of the overcurrent test, the current level of the overcurrent (b in FIG. 8A) applied during the test is the first level.
Since it is larger than the operating current I1 of the iron core 57 and smaller than the operating current I2 of the second iron core 58, the second spring portion 59B bends when the overflow current exceeds the operating current I1, and the first iron core 57 Starts to move, but the overcurrent is the second iron core 58.
Since the operating current I2 is smaller than the operating current I2, the second iron core 58 is not displaced, and therefore the latched state by the latch portion 60 is not released and the contact portion is not forcibly opened.

In the case of the cord short-circuit test, since the cord short-circuit current (C in FIG. 8A) applied during the test exceeds the operating current I2 of the second iron core 58, the cord short-circuit is generated as shown in FIG. 8D. When the current exceeds the operating current I1, the first iron core 57 starts to move to the second iron core 58 side, and when the cord short-circuit current exceeds the operating current I2, the second iron core 58 moves to the first iron core 57 side. To the second iron core 58 and the first iron core 5
When the distance between the contact point and the contact point 7 becomes a predetermined value, the latched state is released and the contact portion is forcibly opened.

Further, in the case of the short-circuit test, a current larger than the cord short-circuit current (for example, about 2500 A) is supplied as shown in D of FIG. 8A. Therefore, as shown in FIG. The cord short-circuit current exceeds the operating currents I1 and I2 at an earlier time than in the above case, and when the short-circuit current exceeds the operating current I1, the first iron core 57 moves to the second iron core 5
8 starts to move to the 8 side, and then the cord short circuit current is the operating current I
When the number exceeds 2, the second iron core 58 starts to move to the first iron core 57 side, and when the distance between the second iron core 58 and the first iron core 57 becomes a predetermined distance, the latched state is released. The contact point is forcibly opened.

As described above, in this embodiment, when the motor starting current exceeding the operating current I2 of the second iron core 58 flows at the time of starting the motor, the first iron core 57 moves toward the second iron core 58. Since the time for the motor starting current to flow is short, the attraction force for attracting the second iron core 58 before the second iron core 58 is attracted to the first iron core 57 side against the spring force of the first spring portion 59A. Since it disappears, it is possible to prevent malfunction due to an instantaneous inrush current such as a motor starting current. On the other hand, when a large current such as a short-circuit current flows, the first iron core 57 resists the spring force of the second spring portion 59B and the second iron core 5 moves.
After moving to the predetermined position to the 8 side, the second iron core 58 is attracted to the first iron core 57 side against the spring force of the first spring portion 59A, and the latched state of the latch portion 60 is released.
The contact can be forcibly opened reliably. In this embodiment, since the lower end of the magnetic pole surface of the first iron core 57 is in contact with the second iron core 58 in the closed state, when the overcurrent such as the short-circuit current flows, the first iron core 57 and the The electromagnetic attraction force generated between the second iron core 58 and the second iron core 58 becomes strong, and the contact portion can be forcibly opened in a short time.

In the closed state shown in FIG. 5,
If an overcurrent flows through the load, the bimetal 46 will generate heat due to the overcurrent and will be curvedly displaced. Here, the bimetal 46 hanging from above is displaced so that the lower end, which is a free end, moves leftward in FIG. 5, and a latch member (second iron core) connected to the lower end of the bimetal 46 via a leaf spring 59. ) 58 provided on the inner surface of the second side case 1B
6 is rotated clockwise with the stopper piece 58c abutting on 6 as a fulcrum. As a result, similarly to the above-described tripping operation due to overcurrent, the latch portion 60 provided on the latch member (second iron core) 58 moves leftward, and the latched state of the rear end portion of the movable contactor 4A is released and opened. Since the driving member 40 moves upward due to the biasing force of the polar spring 53, the movable contactor 4A rotates counterclockwise around the lower shaft 44b of the contact pressure spring 44 as a fulcrum, and the movable contactor 4B moves. The pushing down by 40 disappears and the original state is restored, and the movable contacts 3A, 3
B is separated from each of the fixed contacts 2A and 2B to forcibly open the first and second contact portions. At this time, the movable contactor 4B is bent in the closed state as in the case of the above-mentioned short-circuit current.
Since the movable contact 3A is separated from the fixed contact 2A before the movable contact 3B is separated from the fixed contact 2B by returning to the original state, the second contact of the ground electrode even during the tripping operation due to the overload current. Therefore, the first contact portion of the voltage electrode is opened before the portion.

After that, the bimetal 46 is returned to its original state by cutting off the electric path. Further, since the balance of the spring force and the like is lost by releasing the latched state of the rear end portion of the movable contactor 4A, the handle 6 is rapidly rotated to the opening (OFF) side by the urging force of the handle urging spring 51. Returning and connecting member 43
Moves upwards.

By the way, in the present embodiment, since the drive member 40 is biased upward by the opening spring 53, that is, in the direction in which the movable contact 3A is separated from the fixed contact 2A, the overcurrent trip device 47 is operated as described above. When the first and second contact portions are forcibly opened by the above, the latched state of the movable contactor 4A by the latch plate 58 is released, so that the connecting point (contact point) between the connecting member 43 and the movable contactor 4A (contact point) is released. The movable contactor 4A rotates counterclockwise around the lower shaft 44b) of the pressure spring 44 as a fulcrum, and is in a trip state more than the contact distance between the movable contact 3A and the fixed contact 2A in the open state (see FIG. 4). The distance between the contacts at is large (see FIG. 7). As a result, it is possible to quickly cut the arc generated at the first contact portion during forced opening and shorten the contact opening time.

When the driving member 40 moves downward, the movable contactor 4B formed of a leaf spring is pushed downward to bend and the movable contactor 4A is released from the latched state and driven. Since it returns when the upward movement of the member 40 is no longer regulated, an upward driving force acts on the driving member 40 from the movable contactor 4B when the contact portion is forcibly opened as described above, and the It becomes easy to prevent the welding of the one contact portion. Further, since the biasing force of the opening spring 53 acts on the driving member 40 as a driving force, it becomes easier to prevent the welding of the first contact portion due to the arc.

(Embodiment 2) Embodiment 2 of the present invention is shown in FIG.
It demonstrates based on 0-FIG. The first spring portion 59A
Since the configuration other than the second spring portion 59B is the same as that of the first embodiment, the same components are designated by the same reference numerals and the description thereof will be omitted, and only the characteristic features of the present embodiment will be described. .

In the first embodiment described above, the first spring portion 59A is used.
Since the second spring part 59B and the second spring part 59B are continuously and integrally formed from one spring material, there is an advantage that the number of parts is reduced, but in the present embodiment, the bimetal 46 and the second iron core 58 are provided.
59A of the 1st spring part which connects between and, and the 2nd spring part 5 which connects between the main piece 70a of the conductive plate 70, and the 1st iron core 57.
9B are provided separately, and the first spring portion 59A is provided on the bimetal 46.
By connecting the second iron core 58 via the first iron core 57 via the second spring portion 59B to the conductive plate 70 having the bimetal 46 fixed to the joining piece 70c,
The bimetal 46 is interposed between the first iron core 57 and the second iron core 58. Since the operation of the overcurrent trip device 47 is the same as that of the first embodiment, its explanation is omitted.

Here, the first spring portion 59A is replaced by the second iron core 58.
Away from the bimetal 46 (that is, the first iron core 5
The urging force that urges the second spring portion 5 away from
The first spring portion 59 is configured so that 9B becomes larger than the biasing force that biases the first iron core 57 in the direction away from the second iron core 58.
Since the spring constants of A and the second spring portion 59B are adjusted and the first spring portion 59A and the second spring portion 59B are separately formed, the first and second spring portions 59A and 59B are set to 1 There is an advantage that the spring characteristics can be easily adjusted as compared with the case where a single spring material is continuously and integrally formed. Further, the second iron core 58 and the bimetal 46 are connected via the first spring portion 59A, and the terminal plate 70 to which the bimetal 46 is fixed and the first iron core 57 are connected via the second spring portion 59B. Therefore, the first iron core 57, the second iron core 58, and the bimetal 4
Since 6 and 6 can be handled as one part, the assembling work becomes easy.

(Embodiment 3) FIG. 1 shows Embodiment 3 of the present invention.
It demonstrates based on 3 to 18. Since the configuration other than the overcurrent trip device 47 is the same as that of the first embodiment, the same components are designated by the same reference numerals and the description thereof will be omitted, and only the characteristic features of the present embodiment will be described. explain.

Overcurrent trip device 4 of the first embodiment described above.
7, the both side pieces 57a of the first iron core 57 in the closed state.
By contacting a part of the tip end surface (magnetic pole surface) with the second iron core 58, electromagnetic waves generated between the first iron core 57 and the second iron core 58 when an overcurrent such as a short-circuit current flows. While the attractive force is increased, in the present embodiment, the magnetic pole surface of the first iron core 57 and the second iron core 58 are separated from each other in the closed state, and the upper end portion of the magnetic pole surface of the first iron core 57 is It contacts the regulating rib 109 (positioning portion) provided on the inner surface of the second side case 1B.

The operation of this embodiment will be described below with reference to FIGS.
Will be described with reference to. Note that FIG. 15 shows the open (OFF) state and FIG. 16 shows the closed (ON) state, and the tip surfaces (pole surfaces) of both side pieces 57a of the first iron core 57 are the second iron core 58.
Since the second embodiment is the same as the first embodiment except that the upper end portion is in contact with the regulating rib 109, the description thereof will be omitted.

Here, when an excessive current such as a short circuit current flows in the closed state shown in FIG. 16, a magnetic force is generated in the first iron core 57 of the electromagnetic drive unit 48 constituting the overcurrent trip device 47. The corresponding second iron core (latch member) 58 is first
And, the second spring portions 59A and 59B are attracted and swung against the spring biasing force. Here, since the spring constant of the first spring portion 59A is set to a value larger than the spring constant of the second spring portion 59B, when a suction force is generated between the first iron core 57 and the second iron core 58, First, only the second spring portion 59B is bent, and the first iron core 57 moves the upper end portion of the tip end surface (magnetic pole surface) of the both side pieces 57a that abuts the regulation rib 109 protruding on the inner surface of the second side case 1B. Rotate counterclockwise in the figure as the center,
The lower end portion of the tip end surface (the magnetic pole surface) of the both side pieces 57a is the second iron core 5
Move toward 8. Then, the second spring portion 59B
Is bent to a predetermined position, as shown in FIG.
The lower end of the magnetic pole surface of No. 7 contacts the second iron core 58, and the lower end of the magnetic pole surface of the first iron core 57 is prevented from further displacing to the right in the figure.

When the lower end of the magnetic pole surface of the first iron core 57 contacts the second iron core 58 and the movement of the first iron core 57 is restricted,
When the suction force generated between the first iron core 57 and the second iron core 58 becomes larger than the biasing force of the first spring portion 59A, the first spring portion 59A begins to bend, and the first spring portion 59A and the bimetal. The second iron core 58 with the connection point with 46 as a fulcrum
Rotates counterclockwise in the figure, whereby the latch portion 60 provided on the second iron core (latch member) 58 moves leftward as shown in FIG. 18, and the latched state of the rear end portion of the movable contactor 4A is released. To be done. When the latched state of the rear end of the movable contactor 4A is released, the driving member 40 moves upward due to the biasing force of the opening spring 53, so that the movable contactor 4A supports the lower shaft 44b of the contact pressure spring 44 as a fulcrum. As the movable contact 4B is rotated counterclockwise, the movable contact 4B is restored to its original state without being pushed down by the drive member 40, and the movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B, respectively. The second contact part is forcibly opened. At this time, the movable contactor 4B, which is bent in the closed state as in the case of the tripping operation by the short-circuit current described in the first embodiment, returns to the original state and the movable contact 3B is separated from the fixed contact 2B. Before moving the contact 3A
Is separated from the fixed contact 2A, the first contact portion of the voltage electrode is opened prior to the second contact portion of the ground electrode even during the trip operation due to the short-circuit current (see FIG. 17).

After that, when the magnetic force ceases to be generated in the first iron core 57 of the electromagnetic drive section 48 due to the electric circuit interruption, the second iron core (latch member) 58 returns to its original state by the spring force of the leaf spring 59. Further, since the balance of the spring force and the like is lost by releasing the latched state of the rear end portion of the movable contactor 4A, the handle 6 is rapidly rotated to the opening (OFF) side by the urging force of the handle urging spring 51. Upon returning, the connecting member 43 moves upward.

As described above, also in the present embodiment, when a large current flows in the energizing path, first, the second spring portion 59B bends, and the first iron core 57 is moved to the second iron core 58 side to a predetermined position. When the first spring portion 59A bends to bring the second iron core 58 close to the first iron core 57 side to release the latch, and when an instantaneous rush current flows at the time of starting the motor, The first iron core 57 moves toward the second iron core 58, but since the motor starting current flows for a short time,
The second iron core 58 resists the spring force of the first spring portion 59A to move the first
Before being attracted to the iron core 57 side, the attraction force for attracting the second iron core 58 disappears, and it is possible to prevent malfunction due to an instantaneous rush current such as a motor starting current. On the other hand, when an overcurrent such as a short-circuit current flows, the first iron core 57 moves to the second iron core 58 side to a predetermined position against the spring force of the second spring portion 59B, and then the second iron core 58. Is attracted toward the first iron core 57 side against the spring force of the first spring portion 59A, and the latch portion 6
By releasing the latched state of 0, the contact can be surely forcibly opened. In the present embodiment, since the magnetic pole surface of the first iron core 57 is separated from the second iron core 58 in the closed state, the lower end of the magnetic pole surface of the first iron core 57 contacts the second iron core 58, and Until the second iron core 58 starts to move, the electromagnetic attraction force generated between the first iron core 57 and the second iron core 58 can be weakened, and malfunction may occur due to an instantaneous rush current flowing at the time of starting the motor. Can be further prevented.

(Embodiment 4) FIG. 1 shows Embodiment 4 of the present invention.
This will be described with reference to FIGS. The first spring portion 59A
Since the configuration other than the second spring portion 59B is the same as that of the third embodiment, the same components are designated by the same reference numerals, and the description thereof will be omitted. Only the characteristic features of the present embodiment will be described. .

In the third embodiment described above, the first spring portion 59A is used.
Since the second spring part 59B and the second spring part 59B are continuously and integrally formed from one spring material, there is an advantage that the number of parts is reduced, but in the present embodiment, the bimetal 46 and the second iron core 58 are provided.
59A of the 1st spring part which connects between and, and the 2nd spring part 5 which connects between the main piece 70a of the conductive plate 70, and the 1st iron core 57.
9B are provided separately, and the first spring portion 59A is provided on the bimetal 46.
By connecting the second iron core 58 via the first iron core 57 via the second spring portion 59B to the conductive plate 70 having the bimetal 46 fixed to the joining piece 70c,
The bimetal 46 is interposed between the first iron core 57 and the second iron core 58. Since the operation of the overcurrent trip device 47 is the same as that of the third embodiment, its explanation is omitted.

Here, the first spring portion 59A is replaced by the second iron core 58.
Away from the bimetal 46 (that is, the first iron core 5
The urging force that urges the second spring portion 5 away from
The first spring portion 59 is configured so that 9B becomes larger than the biasing force that biases the first iron core 57 in the direction away from the second iron core 58.
Since the spring constants of A and the second spring portion 59B are adjusted and the first spring portion 59A and the second spring portion 59B are separately formed, the first and second spring portions 59A and 59B are set to 1 There is an advantage that the spring characteristics can be easily adjusted as compared with the case where a single spring material is continuously and integrally formed. Further, the second iron core 58 and the bimetal 46 are connected via the first spring portion 59A, and the terminal plate 70 to which the bimetal 46 is fixed and the first iron core 57 are connected via the second spring portion 59B. Therefore, the first iron core 57, the second iron core 58, and the bimetal 4
Since 6 and 6 can be handled as one part, the assembling work becomes easy.

[0091]

As described above, the invention of claim 1 stores the contact inserted in the energizing electric path between the power source and the load and the force for opening the contact when the contact is closed. It is used in a circuit breaker equipped with an opening and closing mechanism that forcibly opens the contact by force when the contact is released when the contact is closed. A trip device for a circuit breaker that releases the locked state and forcibly opens the contacts when a large current flows, and is formed in a shape in which one end side of a pair of side pieces is connected to each other. A first iron core in which a part of the current-carrying electric path is arranged; and a second iron core that faces the other ends of the both side pieces and is arranged so that at least a part thereof is separated from the both side pieces in a closed state, (2) The first iron core is separated from the second iron core while the second iron core is provided with a locking portion that locks the opening / closing mechanism. First biasing means for biasing the can, by an urging force greater than the biasing force of the first biasing means, second
A second urging means for urging the iron core away from the first iron core is provided, and when a large current flows through the energizing circuit, the first and second
Characterized in that the first iron core and the second iron core are attracted against the urging force of the urging means, and the contact state is forcibly opened by releasing the locking state of the opening / closing mechanism and the locking portion, First
Since the urging force by the second urging means is larger than the urging force by the urging means of No. 1, a large current flows in the energizing electric circuit, and
When the suction force is generated between the iron core and the second iron core, first the first iron core starts to move toward the second iron core side against the urging force of the first urging means, and then the second urging means is used. The second iron core starts to move toward the first iron core when a suction force larger than the biasing force is generated. Therefore, the second iron core provided with the locking portion for locking the opening / closing mechanism starts to move after the first iron core moves, and the timing of releasing the locked state of the opening / closing mechanism to forcibly open the contacts. As a result, when an instantaneous rush current, such as a motor starting current, flows in the energizing circuit, the rush current is absorbed before the second iron core is attracted to the first iron core and moves. Since the current does not flow, there is an effect that it is possible to suppress a malfunction due to such an instantaneous rush current. In the case of short-circuit current, the current does not decrease instantly like inrush current, so the first
After the first iron core starts to move toward the second iron core side against the urging force of the second urging means, the second iron core moves to the first urine when a suction force larger than the urging force of the second urging means is generated. The contact can be forcibly opened by starting to move toward the iron core and unlocking the opening / closing mechanism by the locking part.

According to a second aspect of the present invention, in the first aspect of the invention, the first core and the second core are in contact with each other on one end side of the facing surface and are separated from each other on the other end side of the facing surface in the closed state. When the other end side of the facing surface of the first iron core is attracted to the second iron core side and moved to a predetermined position, the other end side of the facing surface of the first iron core comes into contact and moves further toward the second iron core side. When a momentary rush current flows and an attractive force is generated between the first iron core and the second iron core, the first iron core moves first to the first iron core. The first core begins to move toward the second core side against the biasing force of the first biasing means, and the other end side of the facing surface of the first core comes into contact with the positioning portion, whereby the first core further moves to the second core side. If the inrush current disappears in this state, the No. 1 iron core will return to its original position. There is an effect that malfunction can be prevented by. When a short-circuit current flows and an attractive force is generated between the first core and the second core, the first core first starts moving toward the second core, and the other end of the facing surface of the first core is the positioning portion. By contacting the first core, the first core does not move further toward the second core, and then the second core moves toward the first core against the biasing force of the second biasing means. The contact state can be forcibly opened by releasing the lock state of the opening / closing mechanism by the lock portion, and the other end sides of the facing surfaces of the first core and the second core are in contact with each other in the closed state. So
The attraction force generated between the first iron core and the second iron core can be increased, and the contacts can be forcibly opened in a short time when a short circuit current flows.

According to a third aspect of the present invention, in the first aspect of the invention, the facing surfaces of the first core and the second core are separated from each other in the closed state, and the first core and the second core contact one end side of the facing surface of the first core. It is characterized in that a positioning portion is provided on the body for contacting and rotating the other end side of the facing surface of the first iron core to the second iron core side with the contact portion as a fulcrum. When a suction force is generated between the first iron core and the second iron core, first, the first iron core rotates to the second iron core side with the positioning portion serving as a fulcrum against the urging force of the first urging means. When the other end of the facing surface of the first iron core comes into contact with the second iron core, the first iron core does not move further toward the second iron core. If the inrush current disappears in this state, the first iron core returns to its original position. Since it returns, it is possible to prevent malfunction due to inrush current. Moreover, since the facing surfaces of the first iron core and the second iron core are separated from each other in the closed state, the attraction force generated between the first iron core and the second iron core can be reduced, and malfunction due to an instantaneous rush current can occur. It can be further suppressed. When a short-circuit current flows and an attractive force is generated between the first iron core and the second iron core, the first iron core first starts moving toward the second iron core, and the other end of the facing surface of the first iron core moves to the second iron core. By contacting the iron core, the first iron core does not move further toward the second iron core side, and then the second iron core moves toward the first iron core side against the biasing force of the second biasing means. The contact state can be forcibly opened by releasing the locked state of the opening / closing mechanism by the locking portion.

According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, the energizing circuit is made of bimetal whose free end side is displaced by an overload current, and the second biasing means is made of bimetal. First connecting the end and the second iron core
When the bimetal is displaced by the overload current, the second iron core connected to the bimetal via the first leaf spring is displaced, and the locking state of the opening / closing mechanism by the locking portion is changed. Since the contact can be forcibly opened by releasing and the bimetal and the second iron core are connected via the first leaf spring, the bimetal and the second iron core are handled as one component. Therefore, there is an effect that the assembling work becomes easy.

According to a fifth aspect of the invention, in the fourth aspect of the invention, the first urging means comprises a second leaf spring connecting the first core and the second core, The first iron core, the second iron core, and the bimetal can be handled as one component, which has the effect of facilitating the assembly work.

The invention of claim 6 is characterized in that, in the invention of claim 5, the first leaf spring and the second leaf spring are continuously and integrally formed from one spring material. Since the first leaf spring and the second leaf spring are formed from the material, the number of parts is reduced, and there is an effect that product quality control and storage are facilitated.

The invention according to claim 7 is the invention according to any one of claims 1 to 3, characterized in that the first biasing means and the second biasing means are separate members. Since the urging means and the second urging means are separate members, there is an effect that each can have a desired spring characteristic and the spring characteristic can be easily adjusted.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a trip device according to a first embodiment.

FIG. 2 is an external perspective view of the above.

FIG. 3 is an exploded perspective view of a circuit breaker using the same as above.

FIG. 4 is a side view showing the above-mentioned contact opening state with the first side case removed.

FIG. 5 is a side view showing the above-mentioned closed state, with the first side case removed.

FIG. 6 is a side view showing a state in which the electromagnetic drive unit of the above is being operated, with the first side case removed.

FIG. 7 shows a contact opening state by the electromagnetic drive unit of the above, and FIG.
It is a side view in the state where the side case was removed.

FIG. 8A is a waveform diagram of a current flowing in a conduction path,
(B)-(e) is explanatory drawing which shows operation | movement of the 2nd iron core and 1st iron core at the time of an electric current application.

FIG. 9 is an explanatory diagram illustrating a relationship between a magnetic gap between a first iron core and a second iron core during a trip operation due to an overcurrent such as a short circuit current and a load during an operation.

FIG. 10 is a side view of the trip device according to the second embodiment, in which a partially closed state can be omitted.

FIG. 11 is a side view, part of which is partially omitted, showing a state in which the electromagnetic drive unit is operating.

FIG. 12 is a side view showing a partially omitted state of the contact opening by the electromagnetic drive unit.

FIG. 13 is an exploded perspective view of the trip device according to the third embodiment.

FIG. 14 is an external perspective view of the above.

FIG. 15 is a side view showing a state in which the contacts are opened and the first side case is removed.

FIG. 16 is a side view showing the above-mentioned closed state, with the first side case removed.

FIG. 17 is a side view showing a state in which the electromagnetic drive unit is operating, the first side case being removed.

FIG. 18 is a side view showing a contact opening state by the electromagnetic drive unit of the above, with a first side case removed.

FIG. 19 is a side view of the trip device according to the fourth embodiment, in which a part of the closed state can be omitted.

FIG. 20 is a side view, partly omitted, showing a state in which the electromagnetic drive unit is operating.

FIG. 21 is a side view showing a partially omitted state of the contact opening by the electromagnetic drive unit.

FIG. 22 shows a trip device for a conventional circuit breaker,
(A) is a side view of a closed state, (b) is a side view of an open state by a short circuit current.

FIG. 23 (a) is a waveform diagram of a current flowing through a conduction path,
(B)-(e) is explanatory drawing which shows operation | movement of a 2nd iron core at the time of an electric current application.

[Explanation of symbols] 46 bimetal 47 Overcurrent trip device 57 No. 1 iron core 57a Side piece 58 No. 2 iron core 59 leaf spring 59A First spring part 59B Second spring part 60 Latch

Claims (7)

[Claims] 1. A contact inserted into an energizing electric path between a power source and a load, and a force in a direction for opening the contact when the contact is closed to store the contact and bring the contact into a locked state. It is used in a circuit breaker equipped with an opening and closing mechanism that forcibly opens contacts by force, and locks the contacts when a large current such as a short circuit current or overload current flows in the energizing circuit when the contacts are closed. A trip device for a circuit breaker that releases a state and forcibly opens contacts, and is formed in a shape in which one end side of a pair of side pieces is connected, and a part of a current-carrying electric path is arranged between both side pieces. A first iron core and a second iron core facing the other ends of the both side pieces and at least partially separated from the both side pieces in the closed state are provided, and an opening / closing mechanism is engaged with the second iron core. Providing a locking portion that is in a stopped state and urging the first iron core away from the second iron core The first urging means and the second urging means for urging the second iron core in a direction away from the first iron core by an urging force larger than the urging force of the first urging means are provided, and the energization is performed. When a large current flows through the electric path, the first and second iron cores are attracted to each other against the biasing force of the first and second biasing means, and the locked state between the opening / closing mechanism and the locking portion is released. A circuit breaker tripping device characterized in that the contacts are forcibly opened. 2. The first core and the second core in a closed state.
The iron core abuts on one end side of the facing surface and is separated from the other end side of the facing surface, and the other end side of the facing surface of the first iron core is attracted to the second iron core side and moved to a predetermined position. In this case, the circuit body according to claim 1, wherein the body is provided with a positioning portion that restricts the other end side of the facing surface of the first iron core from abutting and further moving to the second iron core side. Circuit breaker trip device. 3. The first core and the second core in a closed state.
The facing surface is separated from the iron core, abuts on one end side of the facing surface of the first iron core, and the other end side of the facing surface of the first iron core is on the second iron core side with the contact portion as a fulcrum. 2. The body is provided with a positioning portion for rotating the body in a direction.
The trip device for the circuit breaker described. 4. The energizing circuit comprises a bimetal whose free end side is displaced by an overload current, and the second urging means comprises a first leaf spring connecting the free end of the bimetal and the second iron core. The trip device for a circuit breaker according to any one of claims 1 to 3, characterized in that: 5. The circuit breaker according to claim 4, wherein the first urging means comprises a second leaf spring connecting the first core and the second core. Tripping device. 6. The trip device for a circuit breaker according to claim 5, wherein the first leaf spring and the second leaf spring are continuously and integrally formed from a single spring material. 7. The trip of the circuit breaker according to claim 1, wherein the first urging means and the second urging means are separate members. apparatus.