JPH0643996Y2 - Fixed structure of zero-phase current transformer and test circuit unit in earth leakage circuit breaker - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a case in which a main body composed of a ring-shaped iron core and a winding wound around the ring-shaped iron core is incorporated in an earth leakage breaker and is made of a synthetic resin. A zero-phase current transformer that is housed inside and that penetrates the main circuit conductors of each phase all together; and a contact in a synthetic resin case
Main circuit contacts by connecting the ends of the lead wires drawn out from one of the phases on the power supply side of the zero-phase current transformer and the part on the load side of the other zero-phase current transformer The present invention relates to a fixed structure with a test circuit unit for operating a.

[Conventional technology]

Fig. 9 and Fig. 10 show the rated current of the present invention.
An example of the configuration of a small earth leakage breaker of about 30 amps or less is shown.
The figure shows a two-phase earth leakage circuit breaker. As shown in Fig. 10, a case 1 and a cover 2 that can be divided in the left-right direction of the paper surface.
In a space defined by and, on the bottom surface of the case 1, a fixed contact 13 having one end of the thick plate conductor 11 as a power source side terminal 11 and a fixed contact 12 at the other end, and a thin plate. The movable contact 14 is fixed to one end of the conductor and is bimetal at the other end.
The movable contactor 16 which is fastened together with the fixing metal fitting embedded in the bottom surface of the case 1 together with the 18 and the zero-phase current transformer 10 which is soldered or brazed to the bimetal 18 and whose phases are collectively described below ( FIG. 9) includes a main circuit conductor 17 penetrating therethrough and a load-side terminal 19 made of a thick plate conductor soldered or brazed to the main circuit conductor 17, and as shown in FIG. A rectangular insulating case 21 is attached to the inside of the rectangular frame 2 and a zero-phase current transformer 10 is mounted on a printed wiring board 22 arranged on the bottom side of the insulating case 21.
, And the signal current detected by the zero-phase current transformer 10 is input and amplified, and is placed on the same printed wiring board.
An IC (integrated circuit) 23 that outputs a firing signal to 24, an electromagnet 4 to which an exciting current is input from an output terminal of thyristor 24 via a pattern constituent element of printed wiring board 22, an arrester 25, and the like are mounted. Thus, the control section 5 is formed together with the printed wiring board 22. Further, as the opening / closing mechanism 3, although not specifically shown here, the tripping crossbar 3b and the tripping crossbar 3b for holding the operation handle 3a and the opening / closing spring 3c in the stored state are pulled from the holding position by the electromagnet 4. A cross bar 3d or the like is arranged which, when removed, moves in a linear direction by the force of the opening / closing spring 3c to shut off the movable contact 16.

Furthermore, the front side of the zero-phase current transformer 10 (the front side of the paper in FIG. 9,
On the upper surface side in FIG. 12, a fixed contact 6a and a movable contact 6b are provided in a case 32 as shown in FIGS.
A test circuit unit 31 having a pair of contacts and a resistor 6c having this fixed contact 6a at one end of the lead terminal is mounted on the side of the case to insulate the foot 32a of the case 32 as shown in FIG. By being inserted into the groove 21b of the case 21, it is fixed to the zero-phase current transformer 10 via the insulating case 21.

[Problems to be solved by the device]

In such a fixed structure of the zero-phase current transformer and the test circuit unit, when the test circuit unit is fixed to the zero-phase current transformer, the case upper surface of the zero-phase current transformer and the case lower surface of the test circuit unit are Since a gap for wiring the main circuit conductor that penetrates the zero-phase current transformer is required between the two, the legs of the case of the test circuit unit are long and the wall thickness is thin. There is a problem that deformation such as sagging is likely to occur at the time of casting and that the dimensional accuracy is difficult to obtain.

The object of the present invention is to provide a zero-phase current transformer and a test circuit unit in which the fixed structure portion of the cast-molded member is less likely to be deformed while maintaining the simple fixing structure as described above, and the dimensional accuracy is easily obtained. Is to provide a fixed structure.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, in the present invention, a main body composed of a ring-shaped iron core and a winding wound around the ring-shaped iron core, which is incorporated in an earth leakage breaker, is housed in a case made of synthetic resin. And a zero-phase current transformer that penetrates the main circuit conductor of each phase at once, and a contact in a synthetic resin case, and one of the two phases of the main circuit conductor of each phase that is different from the one-phase current transformer power source side And a test circuit unit for operating the main circuit contact by electrically connecting the ends of the lead wires drawn from the other side of the zero-phase current transformer load side of the other phase. A case of the phase-current transformer has a rod-like or plate-like claw portion projecting outward from the case and a claw formed at the tip portion, and a projecting direction at the tip portion projecting from the case in parallel with the claw portion. Bar-shaped or plate-shaped protrusions And a hole into which the claw portion and the protrusion of the zero-phase current transformer case are respectively inserted in the case of the test circuit unit, and the claw portion of the zero-phase current transformer case is formed in each of the holes. The test circuit unit is fixed to the zero-phase current transformer by inserting the projection and the projection, respectively.

[Action]

If the fixed structure of the zero-phase current transformer and the test circuit unit is configured in this way, the heights of the claws and the recesses formed in the case of the zero-phase current transformer are the main ones that penetrate the zero-phase current transformer. Only a height equal to the gap required for wiring the circuit conductor is required, and like the legs of the case of the conventional test circuit unit, a zero-phase current transformer is added in addition to the length required to form this gap. Since it does not have such a large size that the height of the insulating case (reference numeral 21 in Fig. 16) to be housed is required, deformation during molding is less likely to occur,
In addition, the dimensional accuracy can be easily obtained.

〔Example〕

1 to 8 show an embodiment of a fixed structure of a zero-phase current transformer and a test circuit unit according to the present invention. As shown in FIGS. 2 and 3, on the upper surface of the case 20a of the zero-phase current transformer, a claw portion 20c in which a claw is formed at the tip of an elongated plate extending upward from the upper surface, and the claw portion 20c. Parallel to case 20
A convex portion 20b ₁ having a projection formed on the tip of a round bar extending upward from the upper surface of a and a convex portion 20b ₂ having a projection formed on the tip of a rectangular bar are formed on the other hand. As shown in FIGS. 4 and 5, the case 42 includes a case 42.
Holes 42c, 42b ₁ and 42b ₂ into which the claw portion 20c and the convex portions 20b ₁ and 20b _{2 of the} zero-phase current transformer are respectively inserted are formed on the bottom surface of the. As shown in FIG. 6, FIG. 7 and FIG. 8, the case 42 is assembled with a set of contacts having the lead wire end 6a of the resistor 6c as a fixed contact.
The test circuit unit 41 is formed on the case 20a (Figs. 2 and 3) of the zero-phase current transformer 20 housed in the insulating case 27 while approaching the test circuit unit 41 in the direction of the arrow shown in Fig. 1. Claw
20c and the convex portions 20b ₁ and 20b ₂ are provided with holes 42c, 42b ₁ and 42b of the corresponding case 42 (FIGS. 4 and 5) of the test circuit unit.
_When inserted in ₂ , the claw of the claw portion 20c catches on the bottom surface of the case 42 and acts as a retainer, and the test circuit unit 41 has a height H (Fig. 3) between it and the zero-phase current transformer 20. It is fixed to the zero-phase current transformer 20 with a gap maintained.

[Effect of device]

As described above, according to this invention, the main body composed of the ring-shaped iron core and the winding wound around the ring-shaped iron core, which is incorporated in the earth leakage breaker, is housed in the case made of synthetic resin. And a zero-phase current transformer that penetrates the main circuit conductor of each phase at once, and a contact in a synthetic resin case, and one of the two phases of the main circuit conductor of each phase that is different from the one-phase current transformer power source side And a test circuit unit for operating the main circuit contact by electrically connecting the ends of the lead wires drawn from the other side of the zero-phase current transformer load side of the other phase. A case of the phase-current transformer has a rod-like or plate-like claw portion projecting outward from the case and a claw formed at the tip portion, and a projecting direction at the tip portion projecting from the case in parallel with the claw portion. With a rod-shaped or plate-shaped convex portion formed with At the same time, holes for inserting the claws and protrusions of the zero-phase current transformer case are formed in the case of the test circuit unit, and the claws and protrusions of the zero-phase current transformer case are formed in the holes. Since the test circuit unit is fixed to the zero-phase current transformer by inserting each of them, the claws formed on the case of the zero-phase current transformer are retained while maintaining the simplicity of the conventional fixing structure. The length of the convex portion may be equal to the height between the top surface of this case and the bottom surface of the case of the test circuit unit, which is equal to the gap required for the wiring of the main circuit conductor that passes through the zero-phase current transformer. Therefore, unlike the conventional case, the height of the insulating case for accommodating the zero-phase current transformer must be increased in addition to this height. Deformation of claws and protrusions during molding is unlikely to occur and accuracy is obtained. It becomes easier,
The moldability of the synthetic resin case is significantly improved compared to the conventional case.
Further, since the zero-phase current transformer and the test circuit unit are not fixed to each other by using long legs which are apt to be deformed at the time of molding as in the conventional case, there is an effect that workability at the time of fixing work is improved.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a fixing structure and a fixing method of a zero-phase current transformer and a test circuit unit according to an embodiment of the present invention, and FIGS. 2 and 3 are zeros in the embodiment of FIG. The front view and the side view showing the structure of the case of the phase transformer, FIGS. 4 and 5 are the front view and the side view showing the structure of the case of the test circuit unit in the embodiment of FIG. 1, respectively, and FIG. 7 and 8 are a side view, a front view and a plan view of a test circuit unit formed by using a case formed according to the present invention respectively, and FIGS. 9 and 10 are views of an earth leakage breaker, respectively. Partial cross-sectional front view and side cross-sectional view showing the internal structure, FIG. 11 and FIG. 12 are the front view and side view, respectively, showing the structure of the control unit of the earth leakage breaker, FIG. 13, FIG. 14 and FIG. Side view, front view and plan view of the conventional test circuit unit, 16 is an explanatory diagram showing a and a fixing method fixed structure of the conventional zero-phase current transformer and the test circuit Yunitsuto. 6a ... Fixed contact, 6b ... Moving contact, 10, 20 ... Zero-phase current transformer, 17
... conductor (main circuit conductors), 20a ... Case, 20b _1, 20b ₂ ... protrusion, 20c ... claw portions, 31, 41 ... test circuit Yunitsuto, 32, 42 ...
Case, 42b ₁ , 42b ₂ , 42c ... Hole.

Claims (1)

[Scope of utility model registration request] 1. A main body composed of a ring-shaped iron core and a winding wound around the ring-shaped iron core, which is incorporated in an earth leakage circuit breaker, is housed in a case made of synthetic resin, and main circuit conductors for each phase are packaged together. And a zero-phase current transformer that is penetrated through and a contact in a synthetic resin case, and each phase main circuit conductor has a different 2
Main circuit contacts by connecting the ends of the lead wires drawn out from one of the phases on the power supply side of the zero-phase current transformer and the part on the load side of the other zero-phase current transformer It has a fixed structure with a test circuit unit that operates
A case of the zero-phase current transformer projects outward from the case and has a rod-shaped or plate-shaped claw portion having a claw formed at the tip, and a case protruding parallel to the claw from the case and projecting at the tip. With a rod-shaped or plate-shaped convex portion formed with a protrusion in the installation direction, a hole for inserting the claw portion and the protrusion of the zero-phase current transformer case into the case of the test circuit unit is formed, The test circuit unit is fixed to the zero-phase current transformer by inserting the claw portion and the protrusion of the zero-phase current transformer case into the respective holes, and the zero-phase current flow in the earth leakage breaker is characterized. Structure of the tester and test circuit unit.