JP2003045311A - Circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a circuit breaker made easy to manufacture by reducing the number of parts for adjusting tripping characteristic and simplifying the shape. SOLUTION: A conductive plate 70 made of a metal plate is fixed to a second side case 1B by press fitting an extended piece 70b into an insertion-coupling concave part 94b set up on the inside face of the second side case 1B and at same time by press fitting a coupling part with the extended piece 70b in a junction piece 70c into the insertion-coupling concave part 94b, and a bimetal 46 is joined to a tip part of the junction piece 70c. Further, cut grooves 70e, 70e are formed at both side edges in the vicinity of the coupling part with the extended piece 70b in the junction piece 70c. In the meantime, in a first side case fitted to the second side case 1B, a through-hole for adjustment is made penetrated at a position opposing the tip part of the junction piece 70c, and by bending the junction piece 70c from the part of the cut groove 70e with a jig inserted through the through-hole, an initial position of the bimetal is changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker.

[0002]

2. Description of the Related Art As a conventional circuit breaker, Japanese Patent Laid-Open No. 2001-2001
There is one described in Japanese Patent Publication No. 150002. As shown in FIGS. 16 and 17, the circuit breaker described in the above publication has a bimetal 46 that drives an opening / closing mechanism for opening / closing driving the movable contactor when an overcurrent is detected.
The bimetal 46 is connected to the conductive plate 72 connected to the blade receiving spring portion 78. The conductive plate 72 is made of a thin metal material and is formed by being bent in an inverted L shape. The electromagnetic drive portion 48 is fixed to an outer piece 72a that is arranged to face the upper surface of the body of the circuit breaker. The horizontal piece of the upper end L-shaped portion of the bimetal 46 is welded and fixed to the stepped surface of the lower end of the inner piece 72b which is folded back in a U shape from the tip of the inner piece 72a so as to be parallel to the outer piece 72a.

The electromagnetic drive unit 48 includes a fixed iron core 73 having a U-shaped horizontal section by bending a magnetic iron plate in an inverted L shape and bending both ends of the vertical pieces at right angles, a movable iron core 74, and a movable iron core 74. A flat plate 76, which is a horizontal piece integrally formed at a right angle with the fixed iron core 73, is formed inside the outer piece 72a. The fixed iron core 73 is inserted between the fixed core 73 and the plate 72b, and the inverted T-shaped pieces 72d hung from the central portions of both side edges of the outer piece 72a are engaged with the notch grooves 76a in the central portions of both side edges of the flat plate 76. Are fixed to the conductive plate 72.

In the movable iron core 74, the protrusions 74b, 74b projected on the surface on the side of the fixed iron core 73 are attached to the central piece 75 of the leaf spring 75.
The plate spring 75 is swingably supported by being inserted into the holes 75b, 75b formed at the upper end of a and caulking and fixed, and the plate spring 75 fixes both side pieces 75c bent to both sides of the central piece 75a. The locking pieces 75d, which are arranged along the outer surfaces of the both side pieces 73a of the iron core 73 and project inwardly at the tips of the both side pieces 75c, are locked in the recesses 73b formed at the outer corners of the fixed iron core 73. As a result, it is firmly fixed to the fixed iron core 73.

The magnetic pole surface, which is the tip of both side pieces 73a of the fixed iron core 73, faces the movable iron core 74 via the central piece 75a of the leaf spring 75 and the both side pieces 75c, and an excessive current such as a short circuit current is generated. Of the movable iron core 7 due to the magnetic force generated on the magnetic pole surfaces of the both side pieces 73a of the fixed iron core 73 when flowing into the conductive plate 72.
4 is sucked and oscillated to move a driving portion 74a protruding from one end surface of the movable iron core 74, and a tripping mechanism (not shown) for forcibly opening contacts by the driving portion 74a is operated. Let them do it.

When an overcurrent flows through the load, the bimetal 46 heats up due to the overcurrent and bends.
By displacing the lower end of the contact, the tripping mechanism is operated to forcibly open the contact.

Here, the adjusting screw 77 is screwed into a screw hole 76b provided at the center of the flat plate 76 through the insertion hole 72e of the outer piece 72a of the conductive plate 72, and the tip thereof is a horizontal piece of the upper end L-shaped portion of the bimetal 46. Are opposed to each other via an inner piece 72b, and a tool is inserted through a hole provided on the body surface of the circuit breaker, and the adjusting screw 77 is screwed to bend the inner piece 72b, thereby lowering the lower end of the bimetal 46. It is possible to adjust the tripping characteristic of the bimetal 46 by changing the initial position of the.

[0008]

In the above-mentioned conventional example, the conductive plate 72 is formed by being bent in an inverted L shape, and is further folded back in a U shape from the tip of the outer piece 72a to be parallel to the outer piece 72a. However, since the bimetal 46 is welded and fixed to the inner piece 72b, the shape of the conductive plate 72 becomes complicated and it is difficult to manufacture. Further, by pressing the inner piece 72b with the adjusting screw 77 and changing the initial position of the lower end of the bimetal 46, the bimetal 46 is
Since the tripping characteristic is adjusted by the method described above, an adjusting screw 77 for adjusting the tripping characteristic is additionally required, which causes a problem that the number of parts is increased and assembly is troublesome.

The present invention has been made in view of the above problems, and an object of the present invention is to reduce the number of parts for adjusting tripping characteristics and simplify the shape thereof to facilitate circuit breakage. To provide a container.

[0010]

In order to achieve the above-mentioned object, in the invention of claim 1, a contact portion composed of a fixed contact and a movable contact coming in and out of contact with the fixed contact, and a body accommodating the contact portion, A movable contact, which has a movable contact fixed to one end and is movably disposed inside the body, a latch member that latches the other end of the movable contact, and a latch that deforms when an overcurrent flows to the contact and latches A bimetal for forcibly opening the contact part by moving the latch member in a direction to release the latched state of the movable contact member by the member, and the body is formed by connecting the body and the cover. The conductive plate electrically connected to the body is press-fitted and fixed to the body, and the joint piece projecting from this press-fitted portion toward the cover side is formed continuously and integrally, and the joint piece is connected to the press-fitted portion. Cut grooves on both sides near the site It is characterized in that a through hole for adjustment is provided through a portion of the cover facing the tip of the joining piece, and the tip of the jig is inserted through the through hole for adjustment provided in the cover. By bending the joining piece near the part where the kerf is formed at the tip, the initial position of the bimetal can be changed, and the tripping characteristic of the bimetal can be adjusted, and separately to adjust the tripping characteristic. Since it is not necessary to provide the above parts, the number of parts can be reduced and the assembling work can be facilitated. Further, since the bimetal is joined to the joining piece erected from the conductive plate, the shape of the conductive plate can be simplified and the conductive plate can be easily manufactured, as compared with the conventional circuit breaker.

The invention of claim 2 is characterized in that, in the invention of claim 1, both side edges of the tip end portion of the joining piece are brought into contact with the edge of the through hole, and in addition to the action of the invention of claim 1, Since the joining piece is held between the cover and the body by bringing the tip of the joining piece into contact with the edge of the through hole, a force is applied to the joining piece due to the deformation of the bimetal, and the tip position of the joining piece is changed. It is possible to prevent the slippage and prevent the tripping characteristic of the bimetal from changing.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a lid for opening and closing the through hole is provided, and in addition to the action of the first or second aspect of the invention, the through hole is provided. By closing with the lid, it is possible to prevent external force from being applied to the tip end portion of the joining piece after the adjustment and the joining piece is deformed, and the tripping characteristic by the bimetal is changed.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIG.
It will be described in detail with reference to FIGS.

The circuit breaker of the present embodiment has a first side case 1A (cover) and a second side case 1B made of synthetic resin on both sides.
(Body) is connected to the inside of the body 1,
Two fixed contacts 2A, 2B arranged side by side in the width direction and two movable contacts 4A, 4B fixed with movable contacts 3A, 3B facing each of these fixed contacts 2A, 2B so that they can come into contact with and separate from each other.
And an opening / closing mechanism 5 for driving these two movable contacts 4A, 4B, and the movable contacts 3A, 3B are respectively connected to the fixed contacts 2A, 2B via the opening / closing mechanism 5 by the opening / closing operation of the handle 6. The fixed contacts 2A, 2B and the movable contactors 4A, 4B are configured to be brought into contact (separated / opened) with each other.
Are arranged above and below in the height direction of the body 1, and one of the movable contacts 4A, 4B is interposed between the two fixed contacts 2A, 2B in the height direction, and the other is the movable contact 4B. Fixed contact 2A with which the movable contact 3A of the movable contactor 4A comes into contact with and separates from each fixed contact 2A, 2B.
It is arranged at a height position where 3B is separated and does not intersect when viewed from 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 constituting the ground electrode side electric path having the fixed contact 2B at one end is housed in the section defined by the above, 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 are accommodated. 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 lower piece of the terminal plate 11, and the upper end of the extension piece 11a extends to the extension piece 11a. A fixed contactor 12A that is bent at a right angle to the terminal plate 11 and extends outwardly integrally with the terminal plate 11, a fixed contact 2A that is caulked and fixed to the upper surface of one end of the fixed contactor 12A, and is mounted on the lower piece of the terminal plate 11. Placed on the terminal board 11
It is composed of a substantially U-shaped locking spring 13A housed inside. 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 extending in parallel with the bottom portion of the body 1, and the vertical end of one end of the recess portion 9 is placed. The extension piece 11a is arranged along the wall 25, and the vertical wall 25
The fixed contact 12A beyond the upper end of the recess 9 to the outside of the recess 9, and a lateral wall 15 integrally formed outside the recess 9 in the longitudinal direction of the second case 1B so as to be substantially parallel to the bottom of the second case 1B. By disposing the tip of the fixed contactor 12A on the upper side, 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. The terminal plate 11 is formed by integrally extending a T-shaped piece 11b upward from the other end of the upper piece, and the tip of the lateral projection of the upper end of the T-shaped piece 11b is formed on the wall surface of the intermediate case 7. It is placed on the upper end surface of the convex flat portion 22 '. Further, the side surface of the terminal plate 11 is inserted into the pressing piece 13b of the locking spring 13A, and the locking spring 13A is inserted.
A projection 23 for preventing rattling is integrally formed.

The locking 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.
The core wire is press-fitted between the upper end of the locking piece 13a of A and the upper end of the pressing piece 13b, and the core wire is locked by the tip of the locking piece 13a in the pulling direction of the electric wire and the core wire is attached to the upper end surface of the pressing piece 13b. 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 locking spring 13B has the same structure as the locking 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.

A 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 and 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 is provided with a contact pressure spring 44 formed of a torsion coil spring and having both ends bent at substantially right angles to form shafts 44a and 44b, and a guide plate 45 formed in a substantially trapezoidal shape by a metal plate. 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. 12). It is energized.

The upper shaft 44a of the contact 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 the contact pressure spring 44 which penetrates the guide holes 45b of the guide plate 45 into the 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 drive member 40 is formed of a synthetic resin having an insulating property into a substantially rectangular flat plate shape, and the longitudinal direction thereof is aligned with the vertical direction (height direction) of the body 1 in the vertical direction between the both 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, as shown in FIG. 7, a space between the standing wall 31 and the separating wall 14 which are installed from the bottom of the second side case 1B to be substantially parallel to the separating wall 14 extends from the inside surface of the second side case 1B to the standing wall 31 and the separating wall 14. Ribs 111a are formed along the vertical wall 3
1, the lower end portion of the opening spring 53 is inserted and fixed in a concave portion (which is referred to as a “fixed concave portion”) surrounded by the partition wall 1, the isolation wall 14, and the rib 111a. Therefore, the driving member 40 is the opening spring 5
3 is disposed inside the body 1 in a compressed state, and is biased upward by the spring force of the opening spring 53 as shown in FIG. 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. 3 and 4, the overcurrent trip device 47 includes an electromagnetic drive unit 48 for driving the latch plate 58 when an overcurrent such as a short circuit current flows, and 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 fixed iron core 57 formed by bending a magnetic iron plate into a substantially U shape in a plan view, a movable iron core that also serves as a latch plate 58, and a movable iron core (latch member) 58 on both magnetic pole surfaces of the fixed iron core 57. A leaf spring 59 that supports the movable iron core (latch member) 58 so as to be swingably opposed and elastically biases the movable iron core (latch member) 58 in a direction away from the fixed iron core 57.
Composed of and.

The movable iron core (latch member) 58 is made of a metal material (magnetic iron plate) that is harder than the metal material (copper alloy) that forms 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 fixed 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 of the central piece 59a, and a caulking pin 67 is inserted into a hole 46a formed in the lower end of the bimetal 46 to caulk the bimetal 46 to the center. 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 fixed to the fixed iron core 57.
The locking pieces 59d, which are arranged along the outer surfaces of the both side pieces 57a and project inward at the tips of the both side pieces 59c, are locked in the recesses 57b formed at the outer corners of the fixed iron core 57. , The central piece 5 of the leaf spring 59 as shown in FIG.
The bimetal 46 which is erected from the lower end of 9a is fixed to the iron core 5
The leaf spring 59 is fixed to the fixed iron core 57 by being interposed between the movable iron core 7 and the movable iron core (latch member) 58. At this time, the magnetic pole surface, which is the tip of the both side pieces 57a of the fixed iron core 57, causes the leaf spring 59
It faces the movable iron core (latch member) 58 via the central piece 59a and the both side pieces 59c.

The bimetal 46 has one end welded to the movable contact 4A and the other end of the braided wire 79 welded to the plate surface slightly below the center, and the fixed contact 2A and the movable contact 3A.
A conductive plate 70 that forms an electric path on the voltage electrode side that is electrically connected to the contact portion 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 a main piece 7a.
An L-shaped extension piece 70b extending from the upper end of 0a,
The joining piece 70c extends from the tip of the extending piece 70b in parallel with the main piece 70a, and the L-shaped fixing piece 70d extends from the lower end of the main piece 70a. The bimetal 46 is joined to the
A blade receiving spring portion 78 sandwiching a conductive bar (not shown) of a voltage electrode arranged in the distribution board is welded and fixed to the lower end of the blade, and the blade receiving spring portion 78, the conductive plate 70, the bimetal 46, and the braided wire are attached. 79 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 fixed iron core 57 is formed.
Is excited, and the movable iron core (latch plate) 5 is caused by the magnetic force generated on the magnetic pole surfaces at the tips of both side pieces 57a, 57a of the fixed iron core 57.
8 is swung by suction to move the latch portion 60 that latches the rear end portion of the movable contactor 4A. By thus providing the movable 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 overcurrent flows through the load, the bimetal 46 heats up due to the overcurrent and bends.
12 is displaced so as to move leftward in FIG. 12, and a latch member (movable iron core) 58 connected to the lower end portion of the bimetal 46 via a leaf spring 59 is provided on the inner surface of the second side case 1B. The stopper piece 58c that comes into contact with the contact piece 106 is rotated clockwise as a fulcrum. As a result, the latch portion 60 provided on the latch member (movable iron core) 58 moves leftward and the latched state of the rear end portion of the movable contactor 4A is released,
The contacts are forcibly opened.

Here, in the conductive plate 70, the extension piece 70b is press-fitted into the fitting recess 94a provided on the inner surface of the second side case 1B, and the extension piece 70b of the joining piece 70c is fitted into the fitting recess 94b. By press-fitting the connection part with
It is fixed to the side case 1B, and the bimetal 46 is joined to the intermediate portion of the joining piece 70c. On the other hand, an adjusting through hole 82 penetrating the first side case 1A is provided at a portion of the first side case 1A facing the tip of the joining piece 70c. Joining piece 7
0c is arranged (see FIGS. 5, 6, and 9). Further, cut grooves 70e, 70e are formed on both side edges of the joining piece 70c near the connecting portion with the extending piece 70b.

Then, the tip of a jig such as a minus driver is inserted into the body 1 through the through hole 82 of the first side case 1A, and the joining piece 70c is cut into the groove 70e at the tip of the jig.
The upper end position of the bimetal 46 (initial position) by bending in the left and right directions in FIG.
Can be changed to adjust the tripping characteristic of the bimetal 46. The tip of the joining piece 70c is chamfered in the upper and lower corners, and both the upper and lower corners of the tip of the joining piece 70c are brought into contact with the edges of the through hole 82. Is held by the first side case 1A, the tip position of the joining piece 70c (that is, the initial position of the bimetal 46) is not displaced by the force applied to the joining piece 70c by the deformation of the bimetal 46, and the pulling by the bimetal 46 is performed. It is possible to prevent the removal characteristic from changing. In addition, a cap 83 (lid) that detachably closes the through hole 82 is provided, and by closing the through hole 82 with the cap 83, the joining piece 70c can be adjusted after the adjustment.
It is possible to prevent the joining piece 70c from being deformed due to an external force applied to the tip end of the bimetal 46 to displace the initial position of the bimetal 46 and change the tripping characteristic of the bimetal 46.

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. 2, 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 to the fitting groove 94a, 94b provided on the inner surface of the second side case 1B above the locking groove 99, and the extending piece 70b of the conductive plate 70 and the joint are formed. The conductive plate 70 is housed and fixed in the second side case 1B by press-fitting the base of the piece 70c, and the fixed plate 70d of the conductive plate 70 is provided in the space closer to the center than the partition wall 92 along the longitudinal direction of the second side case 1B. The overcurrent trip device 47 to which the bimetal 46 is fixed is housed. The stopper piece 58c of the movable iron core (latch member) 58 projects from the inner surface of the second side case 1B so as to face the joint piece 70c of the conductive plate 71.
The movable core (latch member) 58 is restricted from moving by abutting against 06.

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. 12).

In this manner, 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 thereof are mounted on the second case 1B side by lateral fitting. 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 disposed 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 in the lateral wall 15a.
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 and connected to the second side case 1B side. 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.

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 at the center in the longitudinal direction. When the case 1A and the second-side case 1B are connected to each other to assemble the body 1, as shown in FIG.
Since the braided wire 79 is sandwiched between the inner surface of the side case 1B and the rib 110, the braided wire 79 is positioned on one side in the width direction of the bimetal 46 that is substantially orthogonal to the displacement direction of the bimetal 46 (longitudinal direction of the body 1). can do.
Therefore, when the bimetal 46, which will be described later, is displaced, the braided wire 79
Does not interfere with the displacement characteristics of the bimetal 46 and the braided wire 7
The effect of 9 becomes difficult.

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. 7, 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, as shown in FIG. 10, the horizontal wall 15 provided on the second side case 1B and the vertical wall 33 and the driving member 40 arranged in parallel with the vertical wall 33 isolate the first contact point portion and the second contact point portion from each other,
A sufficient insulation distance can be secured between both contact portions.

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

FIG. 10 shows the open (off) state,
In this open state, the operation portion 6a of the handle 6 is exposed in an inverted manner through the window hole 50, and the rear end portion of the movable contactor 4A and the latch portion 60 of the latch plate 58 are in the 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 and the connecting member 43 is moved, as shown in FIG. The movable contactor 4A is rotated clockwise with the rear end portion latched by the latch portion 60 by the lower shaft 44b of the contact pressure spring 44 as a fulcrum, and the movable contact 3A at the free end is rotated.
To the fixed contact 2A. 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. Contact 4B
Will bend in the direction that moves the free end downwards,
The movable contact 3B at the free end is brought into contact with the fixed contact 2B. Here, the distance that the movable contact 3B moves before coming into contact with the fixed contact 2B (the distance between the contacts of the second contact portion in the open state)
Is shorter than the distance that the movable contact 3A moves until it comes into contact with the fixed contact 2A (distance between the contacts of the first contact portion), so that the movable contact 3B that has a short moving distance to the contact comes first. The second contact part is closed by contact with 2B (Fig. 11).
reference).

When the operating portion 6a of the handle 6 is further rotated counterclockwise, the movable contactor 4A is rotated clockwise while the movable contactor 4B having flexibility is further bent, and the movable contact 3A is moved. To contact the fixed contact 2A
Close the contact. If 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 input state (ON state) of 12 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.
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. Further, 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 separated to open the first contact portion (see FIG. 11). 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 second
Since the distance between the contact points of the contact portion is also made shorter than the distance between the contact points of the first contact portion and the movable contactor 4B is formed of a flexible spring material, the movable contactor is bent in the closed state. The movable contact 3A separates from the fixed contact 2A before the movable contact 3B separates from the fixed contact 2B by returning the movable contact 3B to its original state (see FIG. 11). Move the movable contact 3B upward to move the movable contact 3B.
Is separated from the fixed contact 2B.

By the way, at the time of closing, the movable contact 3B is temporarily assumed.
Even if the movable contact 3A comes into contact with the fixed contact 2A before the movable contact 4B comes into contact with the fixed contact 2B, the movable contact 4A does not bend even when the handle 6 is rotated because the movable contact 4A is made of a rigid body. Since the drive member 40 cannot move downward any further, the movement of the movable contactor 4B is restricted, and it is possible to prevent the movable contact 3B and the fixed contact 2B from contacting and closing the second contact portion. Therefore, when switching from the open state to the closed state, the second electrode on the ground electrode side is closed.
The contact portion (fixed contact 2B and movable contact 3B) is always closed before the first contact portion (fixed contact 2A and movable contact 3A) on the voltage pole side, and the closed state is switched to the open state. When opened, the second contact on the ground electrode side is the first on the voltage electrode side.
The contacts will always open after the contacts. as a result,
It is possible to prevent a large current from flowing to the second contact portion on the grounding electrode side and an arc from being generated at the time of opening / closing, and an inexpensive contact material having low durability can be used for the second contacting portion on the grounding electrode side.

Further, since only the connecting member 43 is interposed between the handle 6 and the movable contactor 4A and the movable contactor 4A is directly latched by the latch plate 58, the number of parts is reduced as compared with the conventional case. The structure can be simplified, and the work of incorporating the parts into the body 1 becomes easy. Here, the latch plate 58 is formed of a member (for example, iron) that is harder than the member (for example, copper alloy) that forms the movable contactor 4A, and the latch plate 58 is formed with respect to the width dimension of the rear end portion of the movable contactor 4A.
Since the width dimension of the latch portion 60 is increased, the rear end of the movable contactor 4A can be prevented from slipping into the latch portion 60 of the latch plate 58 and the load applied to the latch portion 60 can be stabilized.

Further, the movable contactor 4A on the voltage electrode side and the movable contactor 4B on the ground electrode side are made movable in the same direction (the height direction of the body 1), and the drive member 40 is moved to the movable contactors 4A, 4B. Since it is slidably arranged in the body 1 along the direction, the driving member 40 has a simple structure and can be easily incorporated in the body 1.

Now, in the above-mentioned charging state shown in FIG.
If an overcurrent flows through the load, the bimetal 46 will generate heat due to the overcurrent and will be curvedly displaced. Here, as shown in FIG. 13, the bimetal 46 hanging from above is displaced so that the lower end moves leftward in the figure, and a latch member (movable iron core) connected to the lower end of the bimetal 46 via a leaf spring 59. The contact piece 10 provided with 58 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, the latch member (movable iron core) 58
The latch portion 60 provided on the movable contact 4 moves to the left to
Since the latched state of the rear end portion of A is released and the driving member 40 moves upward by the biasing force of the opening spring 53, the movable contactor 4A rotates counterclockwise about the lower shaft 44b of the contact pressure spring 44 as a fulcrum. When the movable contact 4B is rotated to the original state without being pushed down by the driving member 40, the movable contacts 3A and 3B are fixed to the fixed contacts 2A and 3A, as shown in FIG.
2B is separated from each other to forcibly open the first and second contact portions. At this time, as in the above-described opening operation, the movable contact 4A bent in the closed state returns to the original state and the movable contact 3A is fixed before the movable contact 3B is separated from the fixed contact 2B. Since it is separated from 2A, the first contact portion of the voltage electrode is opened before the second contact portion of the ground electrode even during the trip operation due to the overload current.

After that, the bimetal 46 returns to its original state by cutting 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.

Further, in the above-mentioned charging state shown in FIG.
When an excessive current such as a short-circuit current flows, a magnetic force is generated in the fixed iron core 57 of the electromagnetic drive unit 48 that constitutes the overcurrent trip device 47, and the corresponding movable iron core (latch member) 58 is attracted and rocks. Let As a result, similarly to the tripping operation by the short-circuit current described above, as shown in FIG. 15, the latch portion 60 provided on the movable iron core (latch member) 58 moves leftward and the latched state of the rear end portion of the movable contactor 4A. Is released and the driving member 40 is moved upward by the urging force of the opening spring 53, so that the movable contactor 4A rotates counterclockwise about the lower shaft 44b of the contact pressure spring 44 as a fulcrum, and the movable contact 4A moves. Child 4
B is restored to its original state by no longer being pushed down by the driving member 40, and the movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B, respectively, and the first and second contact portions are forcibly opened. At this time, the movable contact 3A is bent before the movable contact 3B is separated from the fixed contact 2B by returning the movable contact 4B bent in the closed state to the original state as in the trip operation by the short-circuit current. Since the fixed contact 2A is separated from the fixed contact 2A, the first contact portion of the voltage electrode is opened before the second contact portion of the ground electrode even during the tripping operation due to the short-circuit current.

After that, when the magnetic force ceases to be generated in the fixed iron core 57 of the electromagnetic drive unit 48 due to the electric circuit interruption, the movable 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.

By the way, in this embodiment, since the driving member 40 is biased upward by the opening spring 53, that is, the movable contact 3A is separated from the fixed contact 2A, as described above, the overcurrent trip device 47 is used. 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 the movable contactor 4A in the trip state is more than the contact distance between the movable contact 3A and the fixed contact 2A in the open state (see FIG. 10). The distance between the contacts becomes large (see FIG. 14). 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.

[0067]

As described above, according to the first aspect of the present invention, a contact portion including a fixed contact and a movable contact that comes in contact with and separated from the fixed contact, a body for housing the contact portion, and a movable contact fixed to one end portion. And a movable contactor that is movably disposed in the body, a latch member that latches the other end of the movable contactor, and a latch member that latches the movable contactor by deforming when an overcurrent flows. And a bimetal for forcibly opening the contact portion by moving the latch member in a direction to release the state. The body is formed by connecting the body and the cover, and is electrically connected to the contact portion. The conductive plate is press-fitted and fixed to the body, and the joint piece protruding from this press-fitted portion toward the cover side is formed continuously and integrally, and cut on both side edges near the connection part with the press-fitted portion of the joint piece. Form a groove and face the tip of the joining piece It is characterized in that a through hole for adjustment is provided through the cover part, and the tip of the jig is inserted through the through hole for adjustment provided in the cover, and a groove is formed in the joining piece at the tip of the jig. It is possible to change the initial position of the bimetal by bending in the vicinity of the part where it is bent, and to adjust the tripping characteristic by the bimetal.There is no need to provide a separate part to adjust the tripping characteristic. This has the effect of reducing the number and facilitating the assembly work. Further, since the bimetal is joined to the joining piece erected from the conductive plate, the shape of the conductive plate can be simplified and the conductive plate can be easily manufactured as compared with the conventional circuit breaker.

The invention of claim 2 is characterized in that, in the invention of claim 1, both side edges of the tip end portion of the joining piece are brought into contact with the edge of the through hole, and in addition to the action of the invention of claim 1, Since the joining piece is held between the cover and the body by bringing the tip of the joining piece into contact with the edge of the through hole, a force is applied to the joining piece due to the deformation of the bimetal, and the tip position of the joining piece is changed. There is an effect that it is possible to prevent the shift and prevent the change of the tripping characteristic by the bimetal.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a lid for opening and closing the through hole is provided, and in addition to the action of the first or second aspect of the invention, the through hole is provided. Closing with the lid has an effect of preventing an external force from being applied to the tip end portion of the joining piece after the adjustment and deforming the joining piece and changing the tripping characteristic by the bimetal.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of essential parts of a circuit breaker according to an embodiment.

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

FIG. 3 is an exploded perspective view of the overcurrent trip device of the above.

FIG. 4 is a perspective view of the overcurrent trip device of the above.

FIG. 5 is a side view of an essential part with the above-mentioned closing cap removed.

FIG. 6 is an external perspective view showing a state in which the same closure cap is removed.

FIG. 7 is a front sectional view of the above.

FIG. 8 is a central sectional view of the above.

FIG. 9 is a top cross-sectional view of the above, which can be partially omitted.

FIG. 10 is a side view showing the open state of the above, with the first side case removed.

FIG. 11 is a side view showing the state during the closing or opening operation of the above, with the first side case removed.

FIG. 12 is a side view showing the same loading state as above, with the first side case removed.

FIG. 13 is a side view showing a moment when the above bimetal is displaced and showing a state in which the first side case is removed.

FIG. 14 is a side view showing a state in which the above-mentioned bimetal is displaced and the contact portion is forcibly opened, and the first side case is removed.

FIG. 15 is a side view showing the moment when the electromagnetic drive unit of the above is operated, with the first side case removed.

FIG. 16 is an exploded perspective view of an overcurrent trip device in a conventional circuit breaker.

FIG. 17 is a perspective view of the overcurrent trip device of the above.

[Explanation of symbols]

1B Second side case 46 bimetal 70 Conductive plate 70b extension piece 70c joint piece 70e kerf 94a, 94b Mating recess

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takehiko Okada             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Tomoyuki Sawada             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor ▲ Taka ▼ Shinji Yama             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Takuya Kagawa             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Takashi Inagi             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company F-term (reference) 5G030 BA06 FC03 XX13 YY06

Claims (3)

[Claims] 1. A contact portion, which comprises a fixed contact and a movable contact that comes in contact with and separates from the fixed contact, a body for accommodating the contact portion, and a movable contact fixed to one end to be movably disposed in the body. The movable contactor, a latch member that latches the other end of the movable contactor, and the latch member is moved in a direction to release the latched state of the movable contactor by the latch member when overcurrent flows to the contact portion. With a bimetal that forcibly opens the contact part, the body is formed by combining the body and the cover, and the conductive plate electrically connected to the contact part is press-fitted and fixed to the body. The joint piece protruding toward the cover side from the joined portion is formed continuously and integrally, and the notch is formed on both side edges near the connecting portion of the joint piece where the press-fitted portion is fixed, facing the tip of the joint piece. Through holes for adjustment in the cover Circuit breaker, characterized in that the set. 2. The circuit breaker according to claim 1, wherein both side edges of the tip portion of the joining piece are brought into contact with the edge of the through hole. 3. The circuit breaker according to claim 1, further comprising a lid which covers the through hole so as to be opened and closed.