JP2000149757A - Earth leakage circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve an assembly structure so that processes for installing components, such as a residual current transformer, a printed circuit board, and a trip coil, into a body case, and processes for wiring, connecting, and soldering the components to each other, can all be carried out in an automatic assembling mode without relying on manual work. SOLUTION: A residual current transformer 8, a trip coil unit 10, and an assembly of a printed circuit board 9 of a leak detection circuit and a printed-circuit board case 12, are installed into a body case, and respective terminals of the printed circuit board are interconnected with each phase of main-circuit conductors, with the secondary side of the residual current transformer, and with the trip coil. The printed circuit board is positioned/disposed above the residual current transformer and trip coil, while connection conductors 3a, 8a, 8b, 10a led out of the main-circuit conductors, residual current transformer, and trip coil, are extended upward and their ends are arranged in positions corresponding to respective terminals of the printed circuit board. With the printed-circuit board case installed in the body case, the ends of the connection conductors 3a are directly inserted in and soldered to perforated lands 9a corresponding to terminals #1 to 8 through connection-conductor through holes 12b opened in a bottom surface of the printed-circuit board case.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth leakage circuit breaker, and more particularly to an assembly structure of an internal mechanism.

[0002]

2. Description of the Related Art First, FIG. 8 shows a conventional structure of an earth leakage circuit breaker. In the drawing, 1 is a main body case of a circuit breaker as a resin molded product combining a lower case 1a and an upper cover 1b, 2 is a power supply terminal, 3 is a load terminal,
4 is a fixed contact, 5 is a movable contact connected to a toggle type opening / closing link mechanism (not shown), 6 is an opening / closing operation handle,
Reference numeral 7 denotes an overcurrent trip unit, 8 denotes a zero-phase current transformer, 9 denotes a printed board on which a leakage detection circuit 9a including an amplifier for a leakage signal (secondary output of the zero-phase current transformer 8) is mounted, and 10 denotes a leakage. A trip coil unit 11 is excited and activated by an output signal of the detection circuit, and 11 is a trip crossbar.

Here, the printed board 9 is housed in the printed board case 12 and is arranged on the bottom side of the main body case 1. At this position, the printed circuit board 9 is placed between the phases of the main circuit (for example, the R phase of the load terminal 3 and the T phase).
A power supply lead wire is connected to the phase conductor) to receive power. A signal lead is provided between the secondary output terminal 8a of the zero-phase current transformer 8 and the input terminal 10a of the trip coil unit 10. A wire (for example, a vinyl-coated wire) 13 is wired. The functions and operations of the earth leakage breaker are well known, and the description thereof is omitted here.

On the other hand, in order to assemble the above earth leakage breaker, the main circuit terminals 2 and 2 are attached to the lower case 1a of the main body case 1.
3, together with the assembly of the switching mechanism including the movable contact 5 and the overcurrent tripping unit 7, as well as the components such as the zero-phase current transformer 8, the assembly unit of the printed board 9, and the trip coil unit 10 in a predetermined position. And finally the upper cover 1b
To complete the product. The wiring between the zero-phase current transformer 8, the printed board 9, and the trip coil unit 10 must be such that the wiring work of the lead wire 13 that requires soldering after the components are assembled in the main body case 1 cannot be performed. From the lead wire between each part in advance on another assembly line.
3 are wired, and the components are incorporated in the main body case 1 in this wired state.

In this case, each terminal formed on the printed board 9 (power supply terminal, signal input terminal for the secondary output of the zero-phase current transformer 8, signal output terminal for the trip coil unit 10).
Are formed, and the lead wires 13 classified by color are manually wired and soldered.

[0006]

However, the above-mentioned conventional structure for assembling the earth leakage breaker has the following problems in terms of workability. (1) The lead wires 13 to be wired between the components of the zero-phase current transformer 8, the printed board 9, and the trip coil unit 10 are manually connected and soldered. Is easy to occur.

(2) When transporting the components connected by the lead wires 13 or assembling them into the main body case 1, troubles such as breakage of the thin lead wires 13 and peeling of the soldered portions are likely to occur.

(3) In order to assemble the parts into the main body case 1 in a state where the parts are connected to each other with the lead wires 13, an automatic assembling method using a robot cannot be adopted in the assembling process of this part. This is a factor in lowering productivity and increasing costs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to solve the above-mentioned problems, to incorporate components such as a zero-phase current transformer, a printed board, and a trip coil into a main body case, and to provide each component. It is an object of the present invention to provide an earth leakage circuit breaker having an improved assembly structure so that wiring, connection, and soldering processes among each other can be performed by an automatic assembly method without relying on manual work.

[0010]

According to the present invention, there is provided, in accordance with the present invention, a printed circuit having a contact opening / closing mechanism, a zero-phase current transformer, a trip coil, and a leakage detection circuit mounted on a main body case. A power circuit breaker in which a power supply terminal, a signal input terminal, and a signal output terminal of the printed circuit board are connected to a phase between main circuit conductors, a secondary terminal of a zero-phase current transformer, and a terminal of a trip coil, respectively. Is housed in a tray-shaped printed board case as a resin molded article, and the printed board case is positioned and arranged above a zero-phase current transformer and a trip coil in which the printed circuit board case is incorporated in the main body case. , The zero-phase current transformer and the trip coil are pulled out from each other and connected to the printed circuit board. The connection conductors are raised upward and their ends correspond to the terminals of the printed circuit board. Resshi, the printed board and assembly of the case in a state where the elaborate incorporation in place of the main body case,
The respective connection conductors and the respective terminals of the printed board are interconnected (claim 1), and are specifically configured in the following manner.

(1) A perforated land corresponding to each terminal of the printed board is formed, and a connection conductor through hole is opened at a position directly below the perforated land on the bottom surface of the printed board case. With the printed board and its assembly assembled into the main body case, the ends of the connection conductors rising from below were directly inserted into the perforated lands of the printed board from the bottom side of the printed board case and soldered. (Claim 2).

(2) The other end of the external connection conductor piece, one end of which is connected to a land corresponding to each terminal of the printed board, is pulled out from the printed board case and arranged in the outer peripheral area thereof, and the assembly of the printed board and the case is assembled. In a state where the external connection conductor pieces are assembled in the main body case, the outer connection conductor pieces and the ends of the respective connection conductors rising from below are abutted and soldered (claim 3).

(3) In the above item (2), the external connection conductor piece connected to each terminal of the printed board is drawn over the side wall of the printed board case to the outer peripheral side thereof (claim 4).

(4) In the above item (2), the external connection conductor piece of the printed board is drawn through the printed board case to the outer peripheral side thereof (claim 5).

(5) In the above item (4), a lead frame is adopted as the external connection conductor piece to be connected to the printed board, and the lead frame is formed integrally with the printed board case and pulled out to the outer peripheral side thereof. .

(6) In the above item (4), the external connection conductor piece of the printed board penetrates the bottom wall of the printed board case and is drawn out to the outer peripheral side thereof (claim 7).

(7) In the above item (6), an insulating cover is attached to the back surface of the printed board case so as to cover the exposed portion of the external connection conductor piece (claim 8).

In the above structure, the assembly of the overcurrent trip unit, the zero-phase current transformer, the trip coil unit, and the printed board and the printed board case is so-called "drop lid type" with respect to the lower case of the main body case. When the unit components are stacked and assembled in a fixed position in the same manner as in the above, the tip of the connection conductor that stands up from the main circuit conductor, the zero-phase current transformer, and the trip coil unit during this assembly process and the periphery of the printed board In this state, the terminals of the leakage detection circuit arranged in the above manner or the external connection conductor pieces connected to the terminals and drawn out to the outer periphery of the printed circuit board case are individually matched and abutted (inserted state). Thus, in the subsequent soldering step, the tool can be inserted from above the main body case to perform the soldering of each part at once. As a result, it is possible to assemble the earth leakage breaker by an automatic assembling method using a robot without any manual operation.

[0019]

FIG. 1 is a block diagram showing an embodiment of the present invention.
A description will be given based on the embodiment shown in FIGS. In the drawings of each embodiment, the same components corresponding to those in FIG. 8 are denoted by the same reference numerals, and description thereof will be omitted.

First, FIGS. 6 and 7 show a basic assembly structure of an earth leakage breaker according to an embodiment of the present invention. That is, in the main body case 1, in addition to parts such as the power supply side terminal 2, the load side terminal 3, the fixed and movable contacts 4, 5 and the contact opening / closing link mechanism of the main circuit, the overcurrent trip unit 7, the zero A phase current transformer 8, an assembly of a printed board 9 and a printed board case 12,
In addition, the trip coil unit 10 is assembled in one corner in the case. 14 is a printed board 9
This is a test switch attached to.

Here, the printed board case 12 is a tray-shaped resin molded product having an open upper surface, and is mounted on the unit case of the overcurrent trip unit 7 and fixed at a fixed position on both left and right sides thereof as described later. Support legs 12a project downward. On the other hand, one end of the overcurrent trip unit 7 is connected to the main circuit conductor (the load-side terminal 3 corresponding to the R phase and the T phase of the R, S, and T phases) to supply a power lead for supplying power to the printed circuit board. (Only one phase is drawn in the figure) is drawn upright. From the zero-phase current transformer 8, connection conductors 8a and 8b are drawn upward as output terminals of the secondary winding and the test winding. Further, from the trip coil unit 10, a connection conductor 10a is similarly drawn up from the trip coil unit 10 as a coil terminal. FIG. 7 shows a zero-phase current transformer 8.
Primary conductors (main circuit conductors) are not shown in abbreviated form.

In the process of assembling the earth leakage breaker, the assembly such as the power supply side terminal 2, the opening / closing link mechanism including the movable contact 5 and the operation handle 6 is mounted on the lower case 1a of the main body case 1 by using an assembly robot. The overcurrent trip unit 7 is inserted into the lower case 1a of the main body case 1 from above and fixed in place. Next, based on the unit case 7a of the overcurrent trip unit 7, the zero-phase current transformer 9 and the trip coil unit 10 are inserted from above the main body case 1 in a "drop-down lid type" so as to be mounted on the unit case 7a. After placing each component in a fixed position and holding it, an assembly containing the printed board 9 in the printed board case 12 (this assembly is assembled on another assembly line) is inserted. Support legs 12 of the case 12
a is fitted into a hole formed on the upper surface of the unit case 7a and fixed at a fixed position.

When the printed board 9 is assembled in a fixed position together with the printed board case 12 in this assembling step, lands (power input terminals, zero-phase current transformers) of terminals formed on the printed board 9 at this position as described later. Or external connection conductor pieces connected to the terminals of the printed board 9 and drawn out to the peripheral area of the printed board case 12 and the connection conductors 3a, 8a, 8b described above. , And 10a individually come into abutment with each other. Then, in a subsequent soldering step, a soldering tool is inserted from above the main body case 1 to solder between each connection conductor and a land of the printed board or an external connection conductor piece. This completes the assembly of the zero-phase current transformer 8, the printed board 9, the trip coil unit 10, and the connection between the components, and finally, the lower case 1a of the main body case 1.
Is covered with the upper cover 1b to complete the product.

Next, the connection conductors 3a, 8a, 8
Some specific examples of the connection method between the printed circuit board 9 and the printed circuit board 9 are shown in FIGS. First, figure
1 (a) to (c) show an embodiment corresponding to claim 2 of the present invention. In this embodiment, in accordance with the arrangement of the connection conductors 3a, 8a, 8b, and 10a rising from the lower side, the periphery of the printed circuit board 9 includes power supply terminals, signal input terminals, and signal output terminals (see FIG. Terminal numbers # 1 and 6 shown on the printed circuit board 1 (a) are power terminals, # 2 and 3 are signal input terminals for the secondary output of the zero-phase current transformer 8, and # 4 and 5 are the test switches described above. A test terminal for flowing a test current (excitation current) to the test winding of the zero-phase current transformer 8 via
# 7 and 8 are signal output terminals for supplying an exciting current to the trip coil 10). Perforated lands (through holes) 9a are formed, and a printed board case 12 for accommodating the printed board 9. The bottom surface of the connection conductor insertion hole 12b is aligned with the land of each terminal described above.
Is open.

When the assembly of the printed board 9 and the printed board case 12 is assembled at a fixed position above the zero-phase current transformer 8 and the trip coil unit 10 in the assembling process described with reference to FIGS. As shown in (b), the tip of the connection conductor 3a is inserted into the perforated land 9a of the printed board 9 through the connection conductor insertion hole 12b opened in the bottom surface of the printed board case 12, and in the subsequent soldering step, FIG. As shown by, the space between the connection conductor 3a and the land of the printed board 9 is soldered (solder is represented by reference numeral 15). In the illustrated example, only the connection conductor 3a for the power supply is illustrated, but the other connection conductors 8a, 8b, and 10a are similarly printed.
And soldered.

FIGS. 2A and 2B show an embodiment corresponding to claims 3 and 4 of the present invention. In this embodiment, one end of the external connection conductor piece 16 is soldered to a land corresponding to each terminal of the printed board 9, and the other end is pulled over the side wall of the printed board case 12 and pulled out to the outer peripheral area of the case. is there. The external connection conductor 16 is formed by using a leaf spring material and is subjected to lead bending at an intermediate portion thereof in an inverted U-shape, and a hole 16a into which a tip of the connection conductor 3a rising from below is inserted. are doing. On the other hand, the connection conductors 3a, 8a, 8b, 1 shown in FIG.
The reference numeral 0a is set up at a position facing the front end in accordance with the arrangement of the external connection conductor pieces 16 described above.

Then, when the assembly of the printed board 9 and the printed board case 12 is assembled at a fixed position above the zero-phase current transformer 8 and the trip coil unit 10 in the assembling process of the earth leakage breaker, as shown in the figure, the connection conductor 3a (Other connection conductors 8a,
8b and 10a) are inserted into the holes 16a of the external connection conductor pieces 16. Thereby, in the subsequent soldering step, between the connection conductors and the external connection conductor pieces 16 can be soldered from above the main body case as in the case of FIG.

On the other hand, in the embodiment corresponding to claim 5 of the present invention shown in FIG. 3, the connection conductors 3a, 8a, 8
External connection conductor pieces 16 for connecting between the terminals 10b and 10a and the terminals of the printed board 9 are assembled through the side wall of the printed board case 12. That is, the external connection conductor piece 1
Reference numeral 6 denotes an L-shaped bent inner end, and the other end thereof extends through the side wall of the printed board case 12 and extends to the outer peripheral area. When the printed board 9 is loaded on the printed board case 12, the L-shaped inner end of the external connection conductor piece 16 is inserted into the perforated land of the printed board 9 from below, and this portion is soldered. .

In the structure shown in FIG. 3, there is a method for assembling the external connection conductor pieces 16 to the printed board case 12, as shown in FIGS. First, in the assembling method shown in FIGS. 4A to 4C corresponding to claim 6 of the present invention, each external connection conductor piece 16 is formed in a pattern on the lead frame 16a, and the printed board case 12 is molded. When doing
The lead frame 16a is inserted into a mold and molded integrally with the case 12. Then, unnecessary portions of the lead frame 16a are lead-cut while leaving the external connection conductor pieces 16. Thereafter, as shown in FIG. 4C, the printed board 9 is loaded on the printed board case 12, and then the tip of the inner end of the external connection conductor piece 16 is inserted into the perforated land of the printed board 9 and soldered. . Thus, the structure shown in FIG. 3 is obtained.

On the other hand, in the method of FIGS. 5A and 5B corresponding to claims 7 and 8 of the present invention, the conductor pieces are inserted into the bottom wall of the printed board case 12 in accordance with the arrangement of the external connection conductor pieces 16. Hole 12
c, and a concave groove 12d extending from the hole to the periphery is formed, and the external connection conductor piece 16 bent in an L shape from the back side of the case 12 is press-fitted into the insertion hole 12c and further connected to the external connection. An insulating plate 17 is attached to the back surface of the case 12 so as to cover the exposed portion of the conductor piece 16 and fixed with an adhesive. The insulating plate 17 serves to prevent the main circuit conductor located thereunder from contacting the external connection conductor piece 16.

[0031]

As described above, according to the structure of the present invention, the overcurrent trip unit, the zero-phase current transformer, the trip coil unit, and the printed circuit board / printed board are mounted on the main body case of the circuit breaker from above. When the unit components of the plate case assembly are stacked one after the other in the so-called "drop lid method" and assembled into a fixed position, in the process of assembling, they stand upward from the main circuit conductor, the zero-phase current transformer, and the trip coil unit. The ends of the drawn connection conductors and the respective terminals of the leakage detection circuit arranged and arranged on the periphery of the printed circuit board or the external connection conductor pieces connected to the terminals and drawn out to the outer periphery of the printed circuit board case individually match. It will be in the state where it was butted.
Thus, in the subsequent soldering step, the tool can be inserted from above the main body case to perform the soldering of each part at once.

As a result, it is possible to assemble the earth leakage breaker by an automatic assembling method by a robot without relying on manual work, and it is possible to improve the productivity of products and reduce costs.

[Brief description of the drawings]

FIG. 1 is a diagram showing a connection structure between a printed board and power, input, and output connection conductors according to an embodiment of the present invention;
Is a layout diagram schematically showing each component, and (b) and (c) are enlarged cross-sectional views showing the connection state just before connection of some conductors and after soldering

FIG. 2 is a diagram showing a connection structure between a printed board and a power supply connection conductor according to an embodiment different from FIG. 1, wherein (a) and (b) are a front view and a side sectional view, respectively.

FIG. 3 is a side sectional view showing a connection structure of an embodiment further different from FIG. 2;

4A and 4B show an embodiment in which a lead frame is adopted as the external connection conductor piece in the connection structure shown in FIG. 3, wherein FIGS. 4A and 4B are a plan view and a side sectional view of the lead frame, respectively; Is a cross-sectional side view showing the assembled state in which the external connection conductor piece is integrally formed with the printed board case and connected to the printed board.

5 shows an embodiment in which the external connection conductor piece is inserted into a printed board case and mounted in the connection structure shown in FIG. 3,
(a) and (b) are side sectional views showing the state before and after mounting, respectively.

FIG. 6 is an internal mechanism diagram showing an assembly structure of the entire earth leakage breaker according to the present invention.

FIG. 7 is an exploded perspective view of main parts in FIG. 6;

FIG. 8 is a diagram showing an assembly structure of a conventional earth leakage breaker.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body case 1a Lower case 1b Upper cover 2 Power supply terminal 3 Load side terminal 3a Power supply connection conductor of a printed board 4 Fixed contact 5 Movable contact 7 Overcurrent tripping unit 7a Unit case 8 Zero phase current transformer 8a, 8b Secondary output connection conductor 9 Printed board 9a Perforated land 10 Trip coil unit 10a Trip coil connection conductor 12 Printed board case 12a Support leg 12b Connection conductor insertion hole 15 Solder 16 External connection conductor piece 16a Lead frame

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Yoshiaki Kawashima 1-1, Tanabe-Nitta, Kawasaki-ku, Kawasaki, Kanagawa Prefecture Inside Fuji Electric Co., Ltd. No. 1 Inside Fuji Electric Co., Ltd. (72) Inventor Makoto Ogasawara 1-1, Tanabe-Nitta, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture F-term inside Fuji Electric Co., Ltd. 5G030 FC05 XX12 YY12

Claims (8)

[Claims] An earth leakage circuit breaker for detecting the occurrence of earth leakage in an electric circuit and opening a main circuit contact, wherein a printed circuit board having a zero-phase current transformer, a trip coil, and an earth leakage detection circuit mounted on a main body case of the circuit breaker. Power supply terminal of the printed board,
The signal input terminal and signal output terminal were connected to the main circuit conductor phase, the secondary side of the zero-phase current transformer, and the trip coil, respectively, and the printed board was housed in a tray-shaped printed board case as a resin molded product. The printed circuit board case is positioned above the zero-phase current transformer and the trip coil, which are incorporated in the main body case, and the printed circuit board case is drawn out of the main circuit conductor, the zero-phase current transformer and the trip coil, respectively. Each connection conductor to be connected to the terminal is raised upward, and its tip is arranged corresponding to each terminal of the printed board, and the assembly of the printed board and its case is incorporated in a fixed position in the main body case, An earth leakage breaker characterized by interconnecting each connection conductor of (1) and each terminal of a printed board. 2. An earth leakage circuit breaker according to claim 1, wherein perforated lands corresponding to each terminal of the printed board are formed, and a position directly below the perforated land corresponding to each of the perforated lands is formed on the bottom surface of the printed board case. In the state where the printed circuit board and its case assembly are assembled in the main body case, the ends of each connecting conductor rising from below are connected to the perforated land of the printed circuit board case from the bottom side of the printed circuit board case. An earth leakage breaker characterized by being directly inserted and soldered. 3. An earth leakage circuit breaker according to claim 1, wherein the other end of the external connection conductor piece, one end of which is connected to a land corresponding to each terminal of the printed board, is drawn out of the printed board case and arranged in an outer peripheral area thereof. An earth leakage circuit breaker, wherein an assembly of a printed board and its case is assembled in a main body case, and the external connection conductor piece and the end of each connection conductor rising from below are joined by soldering. 4. An earth leakage circuit breaker according to claim 3, wherein the external connection conductor piece connected to each terminal of the printed board extends over the side wall of the printed board case and is drawn out to the outer peripheral side thereof. Earth leakage breaker. 5. An earth leakage circuit breaker according to claim 3, wherein the external connection conductor piece of the printed board is drawn through the printed board case to the outer peripheral side thereof. 6. An earth leakage circuit breaker according to claim 5, wherein a lead frame is used for the external connection conductor piece connected to the printed board, and the lead frame is formed integrally with the printed board case and drawn out to the outer peripheral side thereof. An earth leakage circuit breaker. 7. An earth leakage circuit breaker according to claim 5, wherein an external connection conductor piece connected to the printed circuit board penetrates a bottom wall of the printed circuit board case and is drawn out to an outer peripheral side thereof. 8. The earth leakage circuit breaker according to claim 7, wherein an insulating cover is attached to a back surface of the printed board case so as to cover an exposed portion of the external connection conductor piece.