JP3418627B2 - Earth leakage breaker - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth leakage breaker in which the workability of a conductor passing through a zero-phase current transformer is improved.

[0002]

2. Description of the Related Art The prior art of an earth leakage circuit breaker is shown in FIGS. 6 and 7, in the space formed by the case 1 and the cover 2, fixed contacts (not shown) connected to the respective power supply terminals 3a to 3c, and a movable contact that opens and closes with respect to the fixed contacts. (Not shown) are provided. A bimetal 5 as an overcurrent detecting means is connected to the movable contact via a connecting wire 4, and the bimetal 5 and the load terminals 6a to 6a.
6c are connected to each other by a conductor 7. The conductor 7 for each pole is plate-shaped and penetrates the zero-phase current transformer 9. In order to insulate the poles from each other in the portion penetrating the zero-phase current transformer 9. An insulating tube 8 or an insulating tape as shown is attached. In this earth leakage breaker, when the ground fault current flowing through the circuit reaches a predetermined value, the zero-phase current transformer 9 detects it and the detection by the zero-phase current transformer 9 causes the earth leakage detection means 10 to leak the current. The movable contact is separated from the fixed contact by driving the voltage trip device to operate the link mechanism (not shown) in the same manner as during the trip operation.

[0003]

By the way, in the above-mentioned conventional earth leakage breaker, each conductor 7 penetrating the zero-phase current transformer 9 is insulated by the insulating tube 8 or a covering component such as an insulating tape. That portion becomes thicker, so that there is a problem that the conductor 7 hardly penetrates the zero-phase current transformer 9 during wiring. Moreover, when the insulating tube 8 is used, the insulating tube 8 itself may be damaged when the zero-phase current transformer 9 penetrates, and when the insulating tape is used, a defect may occur in the winding work. Therefore, there is a possibility that a defective mounting work of the coated component may occur, resulting in a serious accident. In addition, since the conductor 7 itself has a large shape, it is difficult to accommodate it in a limited space within the earth leakage breaker, resulting in an increase in the size of the entire breaker.

In view of the above circumstances, an object of the present invention is to provide an earth leakage circuit breaker which can improve workability with respect to a zero-phase current transformer even if it has a plurality of conductors, and can downsize the circuit breaker itself. To provide.

[0005]

In the present invention, the main
The conductor of each pole through which the path current flows is penetrated through the zero-phase current transformer
In the earth leakage circuit breaker, the conductor is a plate,
The insulating barrier placed inside the zero-phase current transformer is
And the insulating barrier is formed by fitting the plate conductor.
Provide at least one joint and insulate the plate conductor
Insert into the fitting part of the barrier and transform the insulating barrier into zero-phase current
Placed in a transformer and passing through the zero-phase current transformer.
The conductor is insulated .

[0006]

According to the present invention, the interelectrode insulating barrier is arranged inside the zero-phase current transformer, and the interelectrode insulating barrier can insulate the respective conductors penetrating the zero-phase current transformer from each other. By comparison, it is not necessary to cover each conductor individually. Therefore, it is possible to prevent the conductor from becoming thick,
Since the conductor plate as it is penetrates the zero-phase current transformer, the work of penetrating the zero-phase current transformer can be easily performed. In addition, the conductor does not have to be mounted with insulating parts, and it can be formed into a small size as a whole by bending them appropriately, so it is easy to install in a limited space within the earth leakage breaker. Can be placed at.

[0007]

Embodiments of the present invention will be described below with reference to FIGS. 1 to 4 show a first embodiment of an earth leakage circuit breaker according to the present invention. In the earth leakage breaker of the embodiment, as shown in FIG. 1, a space is formed by the case 11 and the cover 12, and a contact for opening and closing a circuit is built in the space. The contact comprises a fixed contact 14 provided at one end of a fixed contact base 13 and a movable contact 15 provided at one end of a movable contact base 16, the movable contact 15 being the fixed contact 1.
By touching 4 it is possible to energize the circuit. The fixed contact base 13 is fixed to the case 11, and the other end of the fixed contact base 13 is arranged on the outer side of the case 11.
a is configured. The movable contact base 16 is axially supported by the case 11 by a shaft 17, and is urged by a spring 18 to be rotatable counterclockwise in FIG. 1. The spring force of the spring 18 keeps the movable contact 15 constant with respect to the fixed contact 14. I try to make contact with each other. Further, the other end of the movable contact base 16 is connected via a lead wire 19 to a bimetal 2 as an overcurrent detecting means.
0 is connected, and the bimetal 20 has an adjusting screw 2 at the tip.
0a, and the heater 2 is connected to the lead wire 19.
I have one. Further, a load terminal 23 is connected to the bimetal 20 via a conductor 22. In that case, conductor 2
2 are provided for each pole (three in this example corresponding to three phases), and each penetrates the zero-phase current transformer 35. The zero-phase current transformer 35 has a leakage detection means and a voltage trip means (both are not shown in FIG. 1) in which electronic parts such as an IC are mounted at positions apart from the zero-phase current transformer 35.

On the other hand, the shaft 2 is located above the movable contact stand 16.
4, the hook 25 is pivotally supported, and the hook 2
5 is biased counterclockwise by the drive spring 26. A link mechanism section 40 composed of a plurality of link members is connected between the hook 25 and the lower portion of the movable contact base 16, and the link mechanism 40 is arranged such that the hook 25 is rotated counterclockwise from the position shown in FIG. When the movable contact stand 16 is moved to the above position, the movable contact stand 16 is rotated clockwise against the urging force of the spring 18 by performing a trip operation in conjunction with the operation of the hook 25.
The movable contact 15 is opened from the fixed contact 14. On the other hand, the trip metal fitting 27 that engages with the hook 25 is pivotally supported by a pin 28 and is urged clockwise by a spring, and one end thereof is locked by a trip lever 29. The trip lever 29 has the operating rod 3 at the bottom thereof.
0, and the central portion is pivotally supported by the pin 31.
The trip lever 27 is biased in the counterclockwise direction by a spring, and the trip fitting 27 is locked by the end portion near the pin 31 coming into contact with the upper end portion of the trip fitting 27. Then, the trip fitting 27 of the trip lever 29
A relay shaft 32 common to each pole is arranged on the opposite side to the relay shaft 32. The relay shaft 32 is rotatably supported by the case 11 and is biased clockwise by a spring. When the corresponding bimetal 20 is bent by the overcurrent flowing in the circuit of one of the poles, the pressed plate 32a is pressed by the bimetal 20 via the adjusting screw 20a, so that the bimetal 20 operates counterclockwise. It has become. further,
When the relay shaft 32 is actuated by the bending motion of the bimetal 32, the operating rod 30 of the trip lever 29 is pressed against the relay shaft 32.
The trip lever 29 is operated in the clockwise direction to release the engagement between the trip lever 29 and the trip fitting 27.

As shown in FIG. 1, when the fixed contact 14 and the movable contact 15 are in contact with each other and the circuit is in the energized state, when the overcurrent flows, the heater 21 is heated, and the bimetal 20 is moved to the left by the heating. The relay shaft 32 is bent counterclockwise to operate, and the relay shaft 32 pushes the operating rod 30 of the trip lever 29 to push the trip lever 29.
In a clockwise direction about the pin 31, the trip lever 29 releases the locking to the trip fitting 27 by the response, and the trip fitting 27 rotates clockwise by the spring force by the release, whereby the trip fitting 27 is released. 27
Is disengaged from the hook 25, the hook 25 moves counterclockwise by the spring force of the drive spring 26, and the link mechanism 40 trips to move the movable contact stand 16 clockwise. As a result, the movable contact 15 is opened from the fixed contact 14. Further, when the ground fault current flowing through the circuit reaches a predetermined value, the zero-phase current transformer 35
Is detected, the detected signal is amplified by an electric leakage detection means (not shown) to drive the voltage trip device, and the voltage trip device pushes the operating rod of the trip lever 29 to push the trip lever 2
As in the case of detecting the overcurrent, the movable contact 15 is opened by the fact that the link mechanism 40 trips in response to clockwise movement as in the case of overcurrent detection.

Therefore, the relay shaft 32 and the trip lever 2
9, the trip metal fitting 27, and the hook 25 form an overcurrent trip mechanism. Therefore, the circuit breaker, the fixed contact 14, and the contact comprising a movable contact 15, a link mechanism portion 40 for opening and closing the movable contact 1 5 the fixed contact 1 4, in order to tripping the link mechanism portion 40 It is configured to include an overcurrent trip mechanism and a bimetal 20. In FIG. 1, reference numeral 41 is a handle for opening and closing the contacts.

Further, in the earth leakage circuit breaker of the embodiment, each of the conductors 22 penetrating the zero-phase current transformer 35 has an inter-electrode insulating barrier 42.
Insulated from each other. Before describing the inter-electrode insulating barrier 42 in detail, the conductor 22 will be described first. As shown in FIG. 2, the conductor 22 corresponds to three phases, and includes first to third conductor plates 221 to 223. Has become. Of these, the first conductor plate 221 is formed by bending and has one end 221a connected to the heater 21 and
It is a plate body having the other end portion 221b forming the load terminal 23 and a U-shaped intermediate portion 221c. The second conductor plate 222 has a symmetrical shape with the first conductor plate 221. The third conductor plate 223 is bent linearly and in a substantially stepwise manner, and has one end 223a and the other end 223b.
An intermediate portion 223c between and forms a horizontal direction. The inter-electrode insulating barrier 42 is formed of an insulating synthetic resin, and as shown in FIGS.
It is disposed inside the zero-phase current transformer 35, and has a rectangular main body 42a and projectingly provided on both sides of the main body 42a.
The intermediate portion 221c of the first conductor plate 221 and the second conductor plate 222
42b, 42c for respectively holding the intermediate portion 222c of the
And the middle portion 2 of the third conductor plate 223 on the upper part of the main body 42a.
The opposing projections 42d and 42d for holding 23c and the main body 42
It is composed of a leg portion 42e that hangs from the bottom portion of a, and insulates the first to third conductor plates 221 to 223 from each other. When this inter-electrode insulating barrier 42 is inserted into the zero-phase current transformer 35, as shown in FIG. 3, the tips of the legs 42e are formed in the recess 35 of the claw 35a formed in the lower inside of the zero-phase current transformer 35.
b, and the wings 42b and 42c have zero-phase current transformer 35.
It is arranged inside the zero-phase current transformer 35 by being fitted to the support protrusion 35c protruding inside.

Next, the case where the conductor 22 and the inter-electrode insulating barrier 42 are incorporated in the zero-phase current transformer 35 will be described. First,
As shown in FIG. 2, of the conductors 22, the first conductor plate 221 and the second conductor plate 222 are passed through the zero-phase current transformer 35, and the respective intermediate portions 221c and 222c are located in the zero-phase current transformer 35. Keep it. Next, the intermediate portion 223c of the third conductor plate 223 is connected to the facing protrusions 42d of the inter-electrode insulating barrier 42,
Held placed between 42d, which was inserted between the first conductive plate 221 in the zero-phase current transformer 35 and the second conductive plate 222, as shown in FIG. 3, the legs of the interpolar insulation barrier 42 42
e is fitted into the concave portion 35b of the zero-phase current transformer 35, and
The opposing protrusion 42d is fitted to the support protrusion 35c of the zero-phase current transformer 35. As a result, the central portion 2 of the first conductor plate 221
21c is supported on one end of the inter-electrode insulating barrier body 42a by the wing 42b, and the central portion 222c of the second conductor plate 222 is supported on the other side of the body 42a by the wing 42c. Central part 22 of conductor plate 223
Since 3c is supported by the opposing protrusion 42d, the inter-electrode insulating barrier 42 can hold the first to third conductor plates 221 to 223 in an insulated state from each other.

As described above, the inter-electrode insulating barrier 42 is arranged inside the zero-phase current transformer 35, and the inter-electrode insulating barrier 42 causes the respective conductor plates 221 through the zero-phase current transformer 35 to pass through.
Since 223 can be insulated from each other, it becomes unnecessary to cover each of the conductor plates 221 to 223 one by one as compared with the conventional technique. Therefore, it is possible to prevent the conductive plate becomes thick, so penetrates the intact conductor plate ZCT 35, can be easily performed through operations on the zero-phase current transformer 35.
In addition, the inter-electrode insulating barrier 42 has the first to third conductor plates 221.
Since the positions of ~ 223 are relatively fixed, the performance of the zero-phase current transformer 35 itself is stabilized. Further, as described above, not only the conductor plates 221 to 223 do not have the insulating parts mounted thereon, but also they can be appropriately bent to be formed in a small size as a whole. It can be easily placed in the limited space inside the vessel.

FIG. 5 shows another example of the earth leakage breaker of the present invention. In this case, the first through the zero-phase current transformer 35
The third conductor plates 221 to 223 are held in an insulated state by the inter-electrode insulating barrier 42. Inter-electrode insulation barrier 4
Since the configuration of No. 2 is the same as that of the first embodiment, its explanation is omitted here. The difference from the embodiment in this example, the ground fault detector of the zero-phase current transformer 35 is accommodated in an insulating case 36, and the insulating casing 3 6 ZCT 3
It is a point incorporated in 5. That is, this insulating case 36
Is formed of an insulative synthetic resin into a substantially U-shape, and the main body 36a at the center has a shape capable of accommodating an earth leakage detecting means connected to the zero-phase current transformer 35. A central portion 2 of the first conductor plate 221 having a space 36b capable of accommodating the upper portion of the zero-phase current transformer 35 itself and leg portions 36c and 36d on both sides penetrating the zero-phase current transformer 35.
21c, is adapted to be inserted respectively into the second conductive plate 22 2 of the central portion 22 2 c. Then, one leg portion 36c of the insulating case 36 is inserted into the central portion 221c of the first conductor plate 221 protruding to the outside of the zero-phase current transformer 35, and the other leg portion 36d is connected to the zero-phase current transformer. 35 is inserted into the central portion 222c of the second conductor plate 222 which is exposed to the outside of 35, and the main body 36a is placed in the zero phase current transformer 35 so that the upper portion of the zero phase current transformer 35 is housed in the space 36b of the main body 36a. When put on,
The insulating case 36 surrounds the zero-phase current transformer 35. According to this embodiment, the insulating case 36 accommodates the leakage detecting means, and when the insulating case 36 is assembled, the insulating case 36 surrounds the zero-phase current transformer 35, so that when a large current flows in the circuit. It is possible to prevent the welded part of (1) from adhering to the zero-phase current transformer 35 and the leakage detecting means, and thus protect the zero-phase current transformer 35 and the leakage detecting means. In this example, the leakage detecting means is housed in the main body 36a of the insulating case 36, but may be outside the main body 36a and is insulated from the surroundings by the insulating case 36 in any case. May be arranged as follows.

[0015]

As described above, according to the present invention, the inter-electrode insulating barrier is arranged inside the zero-phase current transformer, and the inter-electrode insulating barrier penetrates the zero-phase current transformer. Since the conductors are configured so as to be insulated from each other, it is not necessary to cover each conductor individually as in the prior art, and the conductor plate as it is penetrates through the zero-phase current transformer. The penetration work can be performed easily, and the conductor can be formed in a small size so that the conductor can be easily arranged in a limited space within the earth leakage breaker. There is an effect that the size can be reduced .

[Brief description of drawings]

FIG. 1 is an overall sectional view showing a first embodiment of an earth leakage circuit breaker of the present invention.

FIG. 2 is an exploded perspective view showing the relationship among the conductor plates, the insulating barriers, and the zero-phase current transformer.

FIG. 3 is a front view showing a state in which a conductor plate and an insulating barrier are incorporated in a zero-phase current transformer.

4 is a sectional view taken along the line AA of FIG.

FIG. 5 is an explanatory view showing another embodiment of the earth leakage breaker of the present invention.

FIG. 6 is a partially cutaway front view showing a configuration example of a conventional earth leakage breaker.

FIG. 7 is a partially cutaway side view of the same.

[Explanation of symbols]

11 ... Case, 12 ... Cover, 14 ... Fixed contact, 15 ...
Movable contact, 22 ... Conductor, 221 ... First conductor plate, 222 ...
Second conductor plate, 223 ... Third conductor plate, 25 ... Hook, 27
… Trip metal fittings, 29… tripping lever, 30… operating rod,
32 ... Relay shaft common to each pole, 35 ... Zero-phase current transformer, 36 ...
Insulation case, 40 ... Link mechanism part, 42 ... Inter-electrode insulation barrier.

Continuation of the front page (56) Reference JP-A-3-129630 (JP, A) Actual opening Sho 63-184543 (JP, U) Actual opening Sho 56-107653 (JP, U) Actual public Sho 62-2754 (JP , Y1) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01H 71/00-83/22

Claims (2)

(57) [Claims] 1. A ground fault circuit breaker in which conductors of respective poles through which a main circuit current flows are penetrated through a zero-phase current transformer and wired, wherein the conductor is plate-shaped and arranged inside the zero-phase current transformer. The insulating barrier is formed of an insulating material, and the insulating barrier is provided with at least one fitting portion into which the plate conductor is fitted, and the plate conductor is fitted into the fitting portion of the insulation barrier, and the insulating barrier is zero. An earth leakage circuit breaker, which is arranged in a phase current transformer, wherein each of the plate-shaped conductors penetrating the zero-phase current transformer is insulated. 2. The earth leakage breaker according to claim 1, wherein the fitting portion of the insulation barrier is formed in a concave shape.