JP3329031B2 - Circuit breaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker for forcibly opening a contact according to an abnormal current such as an overcurrent or a short-circuit current.

[0002]

2. Description of the Related Art In general, when power is supplied from a power supply to a load, the power is supplied to a main breaker in a distribution board, and then branched from the main breaker to each branch breaker and then supplied to the load.

[0003] That is, the connection bar on the power supply side of the main breaker is connected to the input terminal of each branch breaker, and the connection bar on the ground side of the main breaker is connected to a neutral switch provided in the distribution board. The power supply side is connected to the load from the output terminal, and the ground side is connected to the load from the neutral switch.

However, in this case, the power supply side led out to the load is led out from the output terminal of the branch breaker, and the ground side is led out from a neutral switch provided at a position remote from the branch breaker. It is necessary to change the lengths of the pair of electric wires on the power supply side and the grounding side, and to connect the wires by routing the inside of the distribution board, which deteriorates the wiring workability.

For this reason, the present applicant has proposed a circuit breaker in which the power supply side and the ground side can be opened and closed with different handles (Japanese Patent Application No. 5-128589). This circuit breaker has a lower surface as a mounting surface, an operation handle and a neutral handle protruding from the upper surface, and a body having a power supply side connection terminal and a ground side connection terminal at both ends, and is connected to the operation handle to operate the operation handle. A link mechanism that opens and closes the power-side contact, and a ground-side connection conductor that is connected to the ground-side connection terminal at one end of the body and extends to the other end.

[0006] The body has attachment portions for attachment to the distribution board on both sides thereof, and the mounting surface is in contact with the distribution board by fitting a fixing member fixed to the distribution board. Fixed at. The ground-side connection conductor is positioned by a separating member for separating the ground-side connecting conductor from the contact portion, and is fixed away from the mounting surface.

[0007]

In the above-described circuit breaker, the body is fixed by the fixing member with the mounting surface in contact with the distribution board, and the ground-side connection conductor is connected to the contact portion. The heat generated by the ground-side connection conductor does not radiate from the inside of the body, which hinders the operation of each member inside the body. there were.

The present invention has been made in view of the above circumstances, and has as its object to release the heat generated in the ground-side connection conductor to the outside, thereby hindering the operation of each member inside the body. An object of the present invention is to provide a circuit breaker that is difficult to perform.

[0009]

In order to solve this problem, the circuit breaker according to the first aspect has openings on both side surfaces.
Body with the components fitted horizontally and the front of the body open
A first cover for closing the mouth and a second cover for closing the opening on the back of the body
A housing is formed from the bar and the lower surface of the housing is used as a mounting surface, the operating handle is projected from the upper surface, and power supply side connection terminals and ground side connection terminals are provided at both ends.
And a link mechanism for opening and closing the supply-side contact by operating a is connected to the operating handle operation handle, the power source
Side contact and one of the power supply side connection terminals at both ends
A connection member to be connected, a ground-side connection conductor connected to the ground-side connection terminal at one end of the body and extending to the other end, and a connection conductor.
Zero-phase current transformer for detecting unbalanced current with the ground side connection conductor
When the unbalanced current is detected by this zero-phase current transformer,
A circuit breaker having a ground fault display device for displaying a ground fault state , wherein the zero-phase current transformer is connected to the first cover side of the body.
From the power supply side to the second cover side.
Is disposed between the body and the first cover, and
Arrange the ground connection conductor between the body and the second cover, and
There a structure <br/> forming the ground-side connecting conductor is brought into contact with the mounting surface of the inner body to.

According to a second aspect of the present invention, there is provided a circuit breaker, wherein the body according to the first aspect includes an arc extinguishing device for extinguishing an arc generated when a power source side contact is forcibly opened above a ground side connecting conductor. An arc chamber is provided, and an arc traveling plate is juxtaposed to the connection conductor.

[0011]

According to the configuration of claim 1, the zero-phase current transformer
Penetrating from the first cover side of the body to the second cover side
And the power supply side contact is disposed between the body and the first cover.
And the ground-side connection conductor is connected to the second body.
Between the cover and the ground-side connection conductor inside the body.
Contact with the power supply side contact and the ground side
Separate from the connection conductor and arrange the connection conductor and ground
The side connection conductor can be passed through the zero-phase current transformer as it is.
In addition, by disposing the mounting surface of the housing in contact with the distribution board, heat generated by the ground-side connection conductor is conducted to the distribution board via the mounting surface.

According to the configuration of the second aspect, the magnetic field due to the current flowing to the power supply side is less likely to be affected by the magnetic field due to the current flowing to the ground side.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. The housing 1 of this circuit breaker
It is formed of an insulating material such as synthetic resin, and has power supply side connection terminals 2 and 3 and ground side connection terminals 4 and 5 on both sides of the circuit. Handle projections 6 and mounting portions 7, 7 for fixing to the distribution board on both sides near the lower surface, and a fixing member (not shown) fixed to the distribution board is fitted. The bottom surface (mounting surface) is fixed in contact with the distribution board. The handle projection 6 has a rectangular window hole 9 into which an operation handle to be described later is inserted, and two operation holes 10 and 1 having a large outside diameter and a small inside diameter through hole.
1 and are provided. As shown in FIG. 2, the housing 1 has a body 12 having an opening on a side surface and having a side-fitting component, and a first cover 13 for closing an opening on the front of the body 12.
And a second cover 14 for closing the opening on the back of the body 12.

The inside of the body 12 has a partition wall 12h substantially at the center.
A link mechanism 15 for interrupting an electric circuit by an arc and an arc extinguishing chamber (arc extinguishing member) 16 for separating and cooling the arc are provided.
It is divided into a section 12A and a second section 12B in which a leakage detection device 17 for detecting a leakage current and a test button 18 are provided. The first section 12A has a concave terminal groove 12a for mounting the ground-side connection terminal 4, and a concave terminal groove 12b for mounting the power supply-side connection terminal 2 of the electric circuit below the terminal groove 12a.
And an arc extinguishing chamber (arc extinguishing member) below the terminal groove 12b.
And an exhaust port 12c for exhausting the gas generated in the exhaust gas. Further, an insulating plate 19 for separating power-supply-side and ground-side connection terminals 2 and 4 from a bimetal, which will be described later, is provided behind the terminal groove 12a. Further, a fitting portion 20 for fitting and fixing an arc traveling plate described below is provided below the arc extinguishing chamber (arc extinguishing member) 16. Also, the first section 12A
In the vicinity of the bottom surface (mounting surface), a ground-side connection conductor housing 21 in which a ground-side connection conductor described later is provided is formed.

The second section 12B has a concave terminal groove 12d for mounting the power supply side connection terminal 3, and a concave terminal groove for mounting the ground side connection terminal 5 above the terminal groove 12d. 12e. Cut grooves 12f and 12g are formed in the upper surface and the lower surface of the second section 12B, respectively. Furthermore, partition walls
A hook shaft 22 for hooking a tension spring to be described later is formed on the side surface of 12h. On the upper part of the partition wall 12h, an electric leakage display device 23 for displaying an electric leakage state is provided.

The first cover 13 covers the front opening of the body 12, and the first cover 13 closes the opening of the body 12.
A link mechanism 15, an arc extinguishing chamber 16 (arc extinguishing device), an electric leakage detecting device 17, a test button 18, an electric leakage display device
And so on. The second cover 14 closes the back opening of the body 12, and holds the neutral device 24, the ground-side connection conductor 24a, and the like disposed in the body 12 with the opening of the body 12 closed. is there.

The link mechanism 15 includes an opening / closing mechanism for manually opening and closing the electric circuit, and an abnormal current detecting unit for opening the electric circuit when an abnormal current flows. The opening and closing mechanism section includes a movable contact 25 whose intermediate portion is pivotally supported by a frame described below,
An opening spring 26 for urging the movable contact 25 in the opening direction, a connection link 27 having one end connected to the movable contact 25, and a shaft supported by the frame together with the operation handle 28 and held at the other end of the connection link 27 Slit 30 that supports the movable shaft 29 that is swingable
a, a trip link 31 that is pivotally supported by the frame and latches the latch link 30, and one end is connected to the connection link 27 via the movable shaft 29 and the other end is the movable shaft.
Handle link connected to operating handle 28 via 32
33, an operation handle 28 held together with the latch link 30 in the frame, and a frame 34 holding these members.
And a power supply side contact 35 interposed between the power supply side connection terminals 2 and 3.

The movable contact 25 is provided with a pair of legs parallel to each other by providing an elliptical slit 25a so that the intermediate portion is pivotally supported by the frame 34, and a connecting piece connecting the legs. The movable contact 25b is fixed to one end of the connecting piece, and a projection for hooking one end of the opening spring 26 is provided at the other end of the connecting piece. In addition, a movable iron core to be described later is inserted through substantially the center of the connecting piece so that the movable contact 25
Hole for forcibly opening the electrode in the opening direction (not shown)
Are formed. The movable contact 25 is electrically connected to the frame 34 via a copper stranded wire 36. Opening spring 26
Is formed in a coil shape, one end of which is hooked on the projection of the movable contact 25 and the other end of which is hooked on a second yoke described later,
The movable contact 25 is urged in the opening direction.

The connecting link 27 is composed of a pair of parallel leg pieces having shaft holes at both ends and a connecting piece connecting the leg pieces from near the shaft hole at one end of the leg piece. To the movable contact 25 via the movable shaft 37,
The other end of the shaft hole is connected to the latch link 30 and the handle link 33 via the movable shaft 29. Latch link 30
A pair of leg pieces which have a shaft hole which is pivotally supported by 34, and which have a slit 30a for swingably supporting the movable shaft 29, are formed in a substantially rectangular shape in side view, and are parallel to each other; And a connecting piece for connecting each other. That is, the connecting link 27 and the handle link 33 are swingably held by the slit 30a via the movable shaft 29.

The trip link 31 is composed of a standing piece and a side piece integrally connected at an intermediate portion of the standing piece, and forms an ear piece on a side opposite to the side piece, and is formed on the side piece and the ear piece. Through the bearing hole. Also, this trip link
A locking portion for locking the connecting piece of the latch link 30 is formed at the tip of the side piece of the 31. Further, there is provided a torsion coil spring 38 which is inserted and supported by the frame 34, is engaged with the side piece and a first yoke described later, and urges the side piece toward the connection side of the latch link 30. At the upper end of the standing piece, a bimetal interlocking portion interlocking with the deformation of the bimetal 39 and a protruding piece provided in a direction intersecting with the bimetal interlocking portion and to which an opening of a first lever described later is attached are provided. At the lower end of the standing piece, a movable core interlocking plate is provided for interlocking movement of a movable iron core to be described later.

The handle link 33 includes a pair of leg pieces having shaft holes at both ends and parallel to each other, and a connecting piece for connecting the leg pieces from the center of the leg pieces.
It is connected to a connection link 27 via 29, and is connected to an operation handle 28 via a movable shaft 32 to a shaft hole at the other end. The operation handle 28 is formed of an insulating material such as a synthetic resin, and has a housing
The swinging part, which swings the operating part protruding from the handle projection 6 on the upper surface of the first housing 1 and the window hole 9 of the housing 1 and has a fan-like shape in a side view, and the frame together with the latch link 30
It has a shaft hole for holding at 34 and a spring shaft hole into which one end of a spring described later is inserted, and a base portion serving as a center of rotation. In addition, a protruding portion having a shaft hole to which a handle link 33 is connected via a movable shaft 32 is provided at one end of the swing portion.

The frame 34 includes a frame body provided integrally with the first yoke 40, and a frame cover connected to the frame body via three fixed shafts 41, 42, 43. The frame main body is formed in a substantially triangular shape with an opening inside when viewed from the side, and has a shaft hole into which the fixed shafts 41, 42, and 43 are inserted at the apexes and two bases, respectively. The first yoke 40 is provided integrally. Like the frame body, the frame cover is formed in a substantially triangular shape with an opening inside when viewed from the side, and has shaft holes into which fixed shafts 41, 42, and 43 are inserted at both ends of the apex and the bottom. are doing. From one end of the bottom side, a leg piece extending downward and a side piece extending in the direction of the frame main body from the tip of the leg piece are continuously provided. One of the copper stranded wires 36 is welded to this frame cover, and the other of the copper stranded wires 36 is
By welding to the frame 25, the frame 34 and the movable contact 25
Are electrically connected.

The power supply side contact 35 is composed of a movable contact 25b fixed to the movable contact 25 and a fixed contact 44a fixed to the connection member 44, and is interposed between the power supply side connection terminals 2 and 3.
The movable contact 25b is provided at one end of the connecting piece of the movable contact 25 as described above. The fixed contact 44a is
At one end.

The connecting member 44 is formed in a substantially L-shape from a connecting member main body 45 connected to the power supply side connection terminal 3 and a fixed contact portion 46 hanging down from the connecting member main body 45. One end of the connection member body 45 is connected to the power supply side connection terminal 3, an insulating material such as vinyl is attached at the center, inserted into a zero-phase current transformer described later, and the other end is held by the partition wall 12h. . Fixed contact 46
Has a fixed contact 44a, is disposed in a state where the fixed contact 44a is fitted in a fitting hole formed in an arc traveling plate described later, and is connected to the power supply side contact 35 such as a short-circuit current or a ground fault current. Even if the fixed contact 44a is melted by the heat of the arc generated when the power supply side contact 35 is forcibly opened by an abnormal current, it does not leak out from the fitting hole to the outside. It is easy to do.

The abnormal current detecting section is composed of a bimetal 39 for detecting an overcurrent and an electromagnet 47 for detecting a short-circuit current. Bimetal 39 has two different thermal expansion coefficients.
The thin plates are integrally laminated, and the whole is bent substantially in an L shape from the vertical piece and the horizontal piece, and generates heat and deforms in accordance with the supplied current. At the upper end of the vertical piece, a screw hole into which the gap adjusting screw is screwed is provided. This bimetal 39
The power supply side connection terminal is welded to the frame
2 Placed near. The detection electromagnet 47 includes a first yoke 40 provided integrally with the frame 34, a fixed core 48 provided on the first yoke 40, a trip link drive rod 49 penetrating the fixed core 48, and a movable core 50. A return spring 51 for urging the movable contact 25 side, a movable iron core 50 for forcibly opening the movable contact 25, a coil cylinder 52 covering them, a coil 53 for winding the coil cylinder 52, And a second yoke 54 connected to the one yoke 40. The first yoke 40 is formed in a substantially U-shape with the upper piece and the lower piece facing each other via a connecting piece,
This upper piece is provided integrally with the frame 34. The fixed core 48 has a through hole, and the tip is fitted into the fitting hole formed in the connecting piece of the first yoke 40 from the inside, and caulked and fixed.

The trip link drive rod 49 is entirely formed in a column shape longer than the fixed core 48, and is swingably inserted through a through hole of the fixed core 48. The return spring 51 is formed in a coil shape, and is compressed and erected between the fixed core 48 and the movable core 50,
The movable core 50 is urged toward the movable contact 25. Movable iron core
50 is slidably fitted in the coil cylinder 52, a forced opening rod protruding from one end thereof projects outside from the small diameter portion of the coil cylinder 52, and a flange is formed at the tip thereof to form a movable contactor.
Through 25 Daruma holes. The coil cylinder 52 has a large diameter portion and a small diameter portion having a through hole, and the small diameter portion is fitted into a fitting hole of a second yoke 54 described later from inside. Coil 53
Is wound around a coil cylinder 52, and one end thereof is bent back in the axial direction and welded to a terminal plate on the power supply side described later. In addition, one end of the copper stranded wire 36 is welded to the other end of the coil 53, and the other end of the copper stranded wire 36 is welded to a vertical piece of the bimetal 39 to be electrically connected to the bimetal 39. The second yoke 54 is composed of a lower piece and side pieces connected to the lower piece, and has a fitting hole into which the small diameter portion of the coil cylinder 52 is fitted. An opening spring is attached to the tip of this side piece.
There is provided a locking portion for locking the movable contact 25 in the opening direction by locking the 51.

The arc extinguishing chamber 16 (arc extinguishing device) has an arc traveling plate 55 for moving an arc generated at the time of short-circuit interruption from a power supply side contact 35 composed of a movable contact 25b and a fixed contact 44a. The separated and cooled gas is exhausted from the exhaust port 12c. The arc traveling plate 55 is formed in a substantially L-shape with a vertical piece and a horizontal piece, and the horizontal piece is fitted to the fitting portion 20 above the ground-side connection conductor housing 21 near the bottom (mounting surface) of the body 12. The vertical pieces are fitted side by side with the ground side connection conductor 24a with the vertical pieces fitted to the partition wall 12h.
5) The magnetic field caused by the current flowing through the
4a) is less susceptible to the magnetic field due to the current flowing through it. For this reason, the arc generated when an abnormal current flows and the movable contact 25b is forcibly opened from the fixed contact 44a can be easily extended by the arc traveling plate 55, and the adverse effect of the ground-side connection conductor 24a can be reduced. As shown in FIG. 7, the vertical piece has, at its center, a fitting hole 55a for fitting the fixed contact 44a, and for example, the movable contact 25b is disconnected by an abnormal current such as a ground fault current or a short-circuit current. Even if the fixed contact 44a melts due to the heat of the arc generated when forcibly opening, the fitting hole
From 55a, it becomes difficult to flow, and it can be reused even after forced opening. In addition, a protruding rib 55b is provided on the center line of the horizontal piece of the arc traveling plate 55 to facilitate traveling of the arc and avoid sticking.

Next, the operation principle of the link mechanism 15 will be described with reference to FIGS. That is, when the operation handle 28 is tilted from the off state side shown in FIG. 1 to the on state side shown in FIG.
The movable shaft 29 moves from the upper side to the lower side through the slit 30a of the latch link 30 in a state of being latched by the movable shaft 29, and the connecting link 27 moves by the movable shaft 29. When the movable shaft 29 moves beyond a straight line connecting the movable shaft 29 and the fixed shaft 42, the movable contact 29 is rapidly reversed, and the movable contact is connected to the connection link 27.
25 rotates around the fixed shaft 41, and as shown in FIG.
The movable contact 25b contacts the fixed contact 44a. At this time, the fixed shaft 41 is located in the middle of the elliptical slit 25a provided in the middle of the movable contact 25, and applies a contact pressure to the movable contact 25b. In the overcurrent trip among the trip states, when an overcurrent flows through the electric circuit in the on state shown in FIG. 1, the trip link 31 is gradually pressed by the self-heating of the bimetal 39, and the connecting piece of the latch link 30 is engaged. It comes off the stop,
The latch link 30 is rotated by the opening spring 26, and the movable contact 25 is fixed to the fixed contact 44a about the fixed shaft 41.
Rotate away from. Then, as shown in FIG. 9, the power supply side contact 35 is opened. The short-circuit trip occurs when the short-circuit current flows in the electric circuit in the ON state shown in FIG.
The movable iron core 50 is sucked by the fixed iron core 48. As a result, the trip link drive rod 49 is pushed out and pushes the movable core interlocking plate of the trip link 31, and the trip link 31 is rotated to release the latch link 30, and the movable contact 25 opens as described above. . However, before the movable contact 25 is opened by such link interlock,
At the same time as the operation of 50, the flange of the movable core 50 is
And the movable contact 25b is fixed to the fixed contact 44.
Separate from a. That is, just before the latch link 30 is tripped, the movable contact 25 rotates about the fixed shaft 41 as a fulcrum in the direction of compressing the opening spring 26 to perform the opening operation.

As shown in FIG. 10, the leakage detecting device 17
A zero-phase current transformer 56 for detecting an unbalanced current in the electric circuit, a control circuit unit (not shown) for amplifying the output of the zero-phase current transformer 56,
A movable contact plate 57 for holding the test button 18 so as to protrude from the housing 1 and an unbalanced current flowing to the zero-phase current transformer 56 via a test circuit unit (not shown) by contacting the movable contact plate 57. And a leakage detection board 59 to which these components are attached. The leakage detection board 59 is arranged near the ground-side connection terminal 5.

The grounding-side connecting conductor 24 is
a forms a slit through which it can pass. The upper end of the earth leakage detection board 59 is formed in the kerf 12f of the body 12 and the lower end is formed in the body.
The earth leakage detecting device 17 is disposed in the housing 1 by being mounted on the 12 kerfs 12g. In addition, the control circuit section includes an amplifier that outputs a signal when an unbalanced current flowing through the electric circuit exceeds the sensitivity current, and a switching element configured with a thyristor that turns on when an output signal of the amplifier is output. It is composed of

The test button 18 is actually operated from the upper surface of the housing 1 and comprises a substantially columnar operating portion and legs extending from the lower surface of the operating portion.
Operation hole 11 so that the operation part protrudes from the upper surface of housing 1.
Attached to. In addition, at the tip of the leg portion, a contact portion which has elasticity by having a cut groove in the center and which locks inside the operation hole 11 when inserted into the operation hole 11 and contacts the movable contact plate 57 when inserted into the operation hole 11 is provided. Provided. When the test button 18 is pressed, the movable contact plate 57 comes into contact with the fixed contact shaft 58, and generates an unbalanced current in the zero-phase current transformer 56 via the test circuit. The test circuit section includes a current limiting resistor for limiting a current, and a test winding.

The electric leakage display device 23 is provided with a housing
1 and a spring 61 for projecting the leakage indicator 60 from the operation hole 10 of the housing 1.
First and second transmission levers 62 and 63 for rotating the trip link 31 to trip the opening and closing mechanism, and a tension spring 64 for pulling the second transmission lever 63 toward the lower surface of the body 12.
And an electromagnet device 65 for rotating the second transmission lever 63 by the current amplified by the control circuit of the leakage detecting device 17. The leakage display member 60 has a columnar shape, and has a display portion that protrudes from the operation hole 10 of the housing 1 when an electric leakage occurs, and a substantially prismatic shape that can be advanced and retracted into the operation hole 10, and one end of a spring 61 is inserted. Kerf and first transmission lever
And a leg portion having a piece to be locked which is locked to 62. The spring 61 is formed in a coil shape, is inserted into the fixed shaft 42, one end is inserted into the spring shaft hole of the operation handle 28, and the other end is inserted into the cut groove of the electric leakage display member 60. It is worn so as to be urged. At the other end, an operation handle 28 is in the neutral position,
When the 28 is shifted to the opening position, the operating handle 28 has an abutting portion that abuts on the other end of the swing portion. First transmission lever
Reference numeral 62 denotes a vertical piece having an opening, and an engagement piece having an engagement portion connected to the vertical piece and engaging with the engagement portion of the second transmission lever 63. An insertion recess into which the fixed shaft 43 of the frame 34 is inserted is provided between the continuous arrangement of the vertical piece and the engagement piece.
By inserting the projecting pieces of the trip link 31 into the openings, the first transmission lever 62 is held by the frame 34 so as to be rotatable.

The second transmission lever 63 has a slanted portion having a locking portion for locking the locked portion of the electric leakage display member 60 at the tip, and a first transmission lever 62 connected to the slanted portion. An engaging piece having an engaging portion for engaging the engaging portion; and an engaging piece continuously provided below the locking portion of the oblique piece and provided in a direction intersecting the oblique piece. It is composed of a hook shaft to be hooked on the portion, and a locking piece that is provided on a side surface of the oblique piece and locks a movable iron core of the electromagnet device 65 described later. A fixed shaft 41 of the frame 34 is provided between the connection of these oblique pieces and the engagement pieces.
Is provided, and the second transmission lever 63 is rotatably held by the frame 34 by mounting the fixed shaft 41 in the insertion recess. According to the present embodiment, the transmission lever for transmitting the output of the leakage detection device to the cutoff mechanism is constituted by two members, but the transmission lever can be applied by any number of members.

The tension spring 64 is formed in a coil shape,
Is hooked on the hook shaft of the transmission lever 63 and the hook shaft 22 of the body 12. The electromagnet device 65 includes a coil bobbin 66 around which a coil is wound, a fixed core 67, a movable core 68, and a yoke 69.
It is composed of The coil terminals at both ends of the coil bobbin 66 are connected to the control circuit unit and the test circuit unit of the leakage detecting device 17 via lead wires (not shown). Fixed iron core
Reference numeral 67 denotes a coil bobbin 66 which is formed in a substantially cylindrical shape and has a cut groove.
And is held by the yoke 69. The movable core 68 includes a columnar movable core body, a continuous shaft connected to the movable core body, and a locked part locked by a locking piece of the second transmission lever 63. It is inserted into a through hole formed in the coil bobbin 66 and the movable core body is prevented from falling off by the holding recess of the yoke 69, so that the movable core 68 does not fall off the coil bobbin 66. yoke
69, the upper piece and the lower piece facing each other are formed in a substantially U-shape via a connecting piece, and the upper piece and the lower piece are unevenly fitted to the flange of the coil bobbin 66, so that the coil bobbin 66 Be attached. Further, the upper piece and the lower piece are provided with holding recesses for holding the cut grooves of the fixed core 67 and the movable core body so as not to fall out of the through holes.

When an unbalanced current flows through the circuit, the circuit breaker detects the unbalanced current by the zero-phase current transformer 56, generates a secondary output, amplifies the output with an amplifier, turns on the switching element, and excites the electromagnet by exciting the coil. When the movable iron core 68 of the device 65 is attracted to the fixed iron core 67 side and the movable iron core 68 pushes up the second transmission lever 63, the second transmission lever 63 rotates about the fixed shaft 41, and the second transmission lever 63 is the first transmission lever 62
, The first transmission lever 62 rotates about the fixed shaft 41, and the trip link 31 inserted into the first transmission lever 62 rotates about the fixed shaft 43. After this,
Similar to the trip operation of the link mechanism 15 described above, the movable contact
25b is pulled off from the fixed contact 44a, and the power supply side contact 35 is opened. Further, the rotation of the second transmission lever 63 causes the leakage indicating member 60 to protrude from the operation hole 10 of the housing 1 and the operation handle 28 to be held at the neutral position. Further, when performing a leakage test, the test button 18 is pressed, the movable contact plate 57 is brought into contact with the fixed contact shaft 58, and a signal is given to the test circuit section. Then, the electromagnet device 65 operates and the movable iron core 68 is attracted. Therefore, as described above, by the link mechanism 15,
The movable contact 25b is detached from the fixed contact 44a.

Further, when the electric leakage indicating member 60 protrudes from the operation hole 10 of the housing 1 due to electric leakage and the operation handle 28 is in the neutral position, when the operation handle 28 is displaced toward the opening position, the operation handle 28 The other end of the swinging part is a spring
The other end 61b of the spring 61 contacts the contact portion 61a formed on the spring 61.
Moves downward in FIG. This allows the spring
The leakage detecting member 60 into which the other end 61b of 61 is inserted is housing
1 is displaced in the inward direction of FIG.
Are locked to the second transmission lever 63. According to this embodiment, when the leakage display member protrudes from the operation hole of the housing and the operation handle is in the neutral position, the leakage display member is moved to the second position by moving the operation handle toward the opening position. Although the lever is locked to the lever, a device that locks the leakage indicating member to the second transmission lever by moving the operation handle toward the closing position can also be applied.

Terminals are power supply side connection terminals 2 and 3 (input / output terminals)
And ground-side connection terminals 4 and 5. The power supply side line connection terminal 2 is a terminal screw with a screwdriver operation hole.
A terminal plate 71 having a screw hole 71a into which the terminal screw 70 is screwed and having a protruding piece 71b connected to the coil 53 of the detecting electromagnet 47; and a nut 72 into which the terminal screw 70 is screwed.
And is arranged in the terminal groove 12b of the first section 12A. Like the power supply side connection terminal 2, the power supply side connection terminal 3 has a terminal screw 73 having an operating hole for a screwdriver and having a chevron shaped contact, and a screw hole 74a into which the terminal screw 73 is screwed. A terminal plate 74 connected to the terminal 44 and a nut 75 into which the terminal screw 73 is screwed.
It is arranged in the terminal groove 12d of 12B.

The ground side connection terminal 4 has a terminal screw 76 having a driver operation hole, a screw hole 77a into which the terminal screw 76 is screwed, and a projection 77b to which the ground side connection conductor 24a is welded. And a nut 78 into which the terminal screw 76 is screwed, and is disposed in the terminal groove 12a of the first section 12A. The ground-side connection terminal 5 has a terminal screw 79 having an operating hole for the driver and having a mountain-shaped contact, a screw hole 80a into which the terminal screw 79 is screwed, and a first neutral fixed contact described later. It is composed of a terminal plate 80 connected in series and a nut 81 into which a terminal screw 79 is screwed, and is arranged in the terminal groove 12e of the second section 12B.

As shown in FIG. 11, the neutral device 24 includes a first neutral fixed contact 90 connected to the ground-side connection terminal 5 at one end, and the first neutral fixed contact 90.
A second neutral fixed contact 91 arranged in parallel with 90, a neutral movable contact 92 which comes into contact with and separates from each of the neutral fixed contacts 90, 91, and a neutral movable contact 92 which is connected to each of the neutral fixed contacts 90, 91 Contact spring 93 for urging
And a neutral handle 94 for bringing the neutral movable contact 92 into and out of contact with the respective neutral fixed contacts 90 and 91 against the bias of the spring; and a neutral handle 94 welded to the second neutral fixed contact 91 and connected to the ground-side connection terminal 4 at the other end. And a ground-side connection conductor 24a to be welded.

The first neutral fixed contact 90 is continuously provided so as to protrude from the terminal plate 80 of the ground-side connection terminal 5 at one end. As shown in FIG. 11, the second neutral fixed contact 91 is juxtaposed to the first neutral fixed contact 90, and is electrically connected to the other ground connection terminal 4 via the ground connection conductor 24a. Have been.

The neutral movable contact 92 has one piece 92A which comes into contact with and separates from the first neutral fixed contact 90, the other piece 92B which comes into contact with and separates from the second neutral fixed contact 91, and the one piece 92A and the other piece 92B. Are formed in a substantially U-shape by a connecting piece 92C for connecting. On the other hand, the piece 92A has a spring receiving portion 92a for mounting the contact spring 93 on a substantially central rear surface thereof.
The contact spring 93 can be mounted between the contact spring 93 and the body 12. The one-side piece 92A is capable of coming into contact with and separating from the first neutral fixed contact 90 by the inner surface of the tip 92b facing the first neutral fixed contact 90. On the other hand, a contact portion of a neutral handle 94 described later abuts on the tip 92c of the other piece 92B, and the neutral handle
Neutral movable contact by rotating 94
92 can be brought into contact with and separated from the respective neutral fixed contacts 90, 91. And this other piece 92B
The outer surface of the base end 92d is the second neutral fixed contact 91
The second neutral fixed contact 91
It can be moved away. This neutral movable contact
Reference numeral 92 denotes a portion from the tip 92b of the one piece 92A to the base end of the other piece 92B.
Up to 92d, a kerf 92e is formed substantially at the center thereof, and when it comes into contact with each of the neutral fixed contacts 90, 91, the current splits and flows, and each of the neutral fixed contacts 90, 91 and the neutral movable contact 92 , The electromagnetic repulsion force can be weakened, and the contact reliability can be improved.

The contact spring 93 is formed by a coil spring.
One end is fitted into the spring receiving portion 92a of the neutral movable contact 92, and the other end is brought into contact with the body 12, thereby biasing the neutral movable contact 92 toward the neutral fixed contacts 90 and 91. The neutral handle 94 has a knitted center cam shape, has a shaft hole 94a rotatably held by a bearing (not shown) of the body 12, and has an operating portion 94b and a contact portion 94c at predetermined peripheral positions. are doing.

As shown in FIG. 11, the ground-side connection conductor 24a has one side welded to the second neutral fixed contact 91 and the other side welded to the ground-side connection terminal 4 at the other end.
By operating the neutral handle 94 to the position shown in FIG. 11, the ground connection terminals 4 and 5 at both ends are electrically connected. The ground-side connecting conductor 24a is connected to the second
The neutral fixed contact 91 is inserted through the zero-phase current transformer 56, is drawn through the ground-side connection conductor housing 21 formed in the body 12, is welded to the ground-side connection terminal 4 at the other end, and is connected to the ground side. By being disposed in the conductor housing portion 21, it is disposed in contact with the bottom surface (mounting surface) of the body 12, and when attached to a distribution board or the like, heat generated in the ground-side connection conductor 24a is externally generated. Therefore, heat is easily dissipated, so that operation of each member (particularly, bimetal) inside the body 12 is hardly hindered.

In the neutral device 24, when the operating portion 94b of the neutral handle 94 is oriented vertically, the contact portion 94c does not contact the neutral movable contact 92, as shown in FIG. The force causes the tip 92b of one piece 92A to contact the first neutral fixed contact 90 and the other piece 92B
The base end 92d contacts the second neutral fixed contact 91, and the ground-side connection terminals 4, 5 at both ends of the body 12 become conductive. When the operating portion 94b of the neutral handle 94 is rotated in the horizontal direction from this state, the contact portion 94c of the neutral handle 94 comes into contact with the contact portion 92c of the other piece 92B. When the rotation operation is further continued, the first neutral fixed contact 90 to the neutral movable contact 92 have one piece 92A.
However, the other piece 92B of the neutral movable contact 92 separates from the second neutral fixed contact 91. At this time, the neutral handle 94 is frictionally locked while the contact spring 93 is compressed by the neutral movable contact 92.

[0045]

Effects of the Invention] According to the circuit breaker according to claim 1, before
The zero-phase current transformer is connected from the first cover side to the second cover side of the body.
And the power supply side contact is connected to the body with the first
And the ground-side connection conductor
Arranged between the body and the second cover, and further connected to the ground side
Since the body is in contact with the mounting surface inside the body,
The contact and the ground-side connection conductor are separated and
Connection conductor and ground-side connection conductor penetrate the zero-phase current transformer as it is
Power supply side contact and ground side connection conductor
Connection with the connection conductor and the ground side
The work of passing the conductor through the zero-phase current transformer is facilitated. I
Since the heat generated at the ground-side connection conductor is conducted to the distribution board via the mounting surface by arranging the mounting surface of the camo in contact with the distribution board, the heat generated at the ground-side connection conductor Is released to the outside, so that the operation of each member inside the body is hardly hindered.

According to the circuit breaker of the second aspect, the magnetic field due to the current flowing through the power supply side line is less likely to be affected by the magnetic field due to the current flowing through the ground side line. , The arc generated when the movable contact is forcibly opened from the fixed contact can be easily extended by the arc traveling plate, so that the adverse effect of the ground-side connection conductor can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing a state where a first cover of FIG. 1 is attached.

FIG. 3 is a side view of the neutral device shown in FIG. 2;

FIG. 4 is a top view of that of FIG.

FIG. 5 is a side view of the device of FIG. 2 on the side opposite to the neutral device side.

FIG. 6 is an exploded perspective view of FIG. 2;

FIG. 7 is an exploded perspective view of FIG. 6 further exploded.

FIG. 8 is a front view showing the on state of FIG. 1;

FIG. 9 is a front view showing a tripped state of FIG. 8;

FIG. 10 is a diagram for explaining a trip operation due to electric leakage, and is a side view showing a state in which a first cover of FIG. 2 is removed.

FIG. 11 is a rear view showing the state of FIG. 2 with the second cover removed.

FIG. 12 is a perspective view showing a ground-side movable contact (movable contact) of FIG. 10;

[Explanation of symbols]

 2,3 Power supply side connection terminal 4,5 Ground side connection terminal 12 Body 15 Link mechanism 16 Arc extinguishing chamber 21 Ground side connection conductor housing 24a Ground side connection conductor 28 Operation handle 35 Power side contact 55 Arc traveling plate

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-33229 (JP, A) JP-A-56-97935 (JP, A) JP-A-5-47285 (JP, A) 135347 (JP, U) Jpn. Sho 62-98141 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01H 73/04

Claims (2)

(57) [Claims] 1. A part has an opening on both side surfaces and a part is laterally fitted.
Body and first cover to close the opening in front of the body
And the second cover that covers the opening on the back of the body
Power by forming a grayed, the lower surface of the housing with power-side connection terminal and the ground-side connecting terminal at both end portions are made to protrude from the operating handle from the top surface to the mounting surface, is connected to the operating handle to operate the operating handle The link mechanism that opens and closes the side contacts, and the power supply side contacts and the power supply side connection terminals at both ends
A connection member for connecting one of the two, a ground-side connection conductor connected to the ground-side connection terminal at one end of the body and extending to the other end, and an unbalanced current between the connection conductor and the ground-side connection conductor are detected.
Outgoing zero-phase current transformer and the unbalanced current
A leakage display device that displays a leakage state when a current is detected;
Wherein the zero-phase current transformer is connected to the second cover from the first cover side of the body.
The power supply side contact is connected to the body
1 cover and the ground-side connection conductor
Is disposed between the body and the second cover, and the ground-side connection conductor is brought into contact with a mounting surface inside the body. 2. An arc extinguishing chamber for extinguishing an arc generated when a power supply side contact is forcibly opened is provided above the body on which a ground side connection conductor is disposed, and an arc traveling plate is provided on the body. The circuit breaker according to claim 1, wherein the circuit breaker is arranged in parallel with the ground-side connection conductor.