JPH0526682Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is a circuit breaker that detects the current of the main electric circuit with a Hall element and interrupts the main electric circuit when the output of the Hall element exceeds a predetermined value. Regarding.

[Conventional technology]

This type of circuit breaker is divided into a main electric circuit, a current sensor, a switching section, and an operating section, and one shown in FIG. 3 is known. In FIG. 3, a main electric circuit 1 drawn in from the outside is connected to a main circuit conductor 3 of a circuit breaker with a terminal screw 2, and a movable contact 4 connected to this main circuit conductor 3 and a movable contact 4 connected to the main circuit conductor 3. A fixed contact 5 facing the circuit breaker constitutes an opening/closing section, and this fixed contact 5 is further connected to an external main electric circuit via a terminal screw (not shown) to constitute a main electric circuit within the circuit breaker. The current sensor that detects the current in the main electric circuit includes an iron core 6, a Hall element 7, and an amplifying section 11 that amplifies the Hall voltage output from the Hall element 7. The iron core 6 surrounds the main circuit conductor 3. A slit is provided at right angles to the magnetic path of the iron core 6, and a Hall element 7 fixed to a mounting board 8 is inserted into this slit.
Two lead wires 9 for energization and two lead wires 10 for deriving Hall voltage are drawn out from the Hall element 7 and connected to an amplifying section 11 mounted on a printed wiring board 12, and the output terminal of this amplifying section 11 is connected to the tripping coil 13. The operating section for performing the tripping operation of the opening/closing section includes a tripping coil 13, a closing spring 14, a toggle link 15, and a handle 16. The toggle link 15 is operated with the handle 16 to change the movable contact 4 to the fixed contact 5. This toggle link 15 is locked by both latches 17 and 18. The tripping coil 13 has both latches 17 and 18
Make an action to pull it out.

When a current flows through the main circuit conductor 3, the magnetizing force surrounding the conductor 3 generates a magnetic flux in the iron core 6 and its slit, and this magnetic flux interlinks with the Hall element 7 at right angles, thereby generating a Hall voltage in the Hall element 7. When the current in the main circuit conductor 3 exceeds a predetermined value, the Hall voltage exceeds a predetermined value, so the amplifying section 11 energizes the tripping coil 13, tripping both latches 17 and 18, breaking the toggle link 15, and moving the movable contact. 4 is pulled away from the fixed contact 5 to shut off the opening/closing section.

[Problem that the invention attempts to solve]

The conventional circuit breaker as described above has a Hall element 7
The four lead wires 9 and 10 derived from the wire must be wired long and connected to the printed wiring board 12, and since both lead wires 9 and 10 are very thin, wiring work takes time and is easy to break. There is a problem. Further, an iron core 6 surrounding the conductor 3 is required, and a mounting board 8 is required to insert the Hall element 7 into the slit of the iron core 6, resulting in a complicated structure and increased cost.

An object of the present invention is to provide a circuit breaker having a simple and inexpensive current sensor by shortening the lead wire between the Hall element and the amplifier section.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention includes a main circuit conductor, a Hall element that detects the current in the main circuit conductor, amplifies the output of this Hall element, and uses this output to control the switching section connected to the main circuit conductor. In a circuit breaker equipped with an amplifier section that drives an operation section that performs a tripping operation, a coil section is formed on the main circuit conductor, and the Hall element and the amplifier section are mounted on the same printed wiring board, The part of the printed wiring board on which the Hall element is mounted is inserted into the coil part.

[Effect]

We focused on the fact that even if the coil part formed on the main circuit conductor has an air core, a large magnetic flux density can be obtained by increasing the number of turns. The Hall element is directly fixed to the printed wiring board, and the majority of the connections between the Hall element and the amplifier are printed wiring, and the current sensor does not use an iron core or mounting board, making it easy to use and eliminate weak points. Except for this, it is compactly assembled.

〔Example〕

An embodiment of the present invention is shown in FIGS. 1 and 2. In FIG. 1, a main circuit conductor 3 is connected to a main electric circuit drawn in from the outside as in the conventional one, but this main circuit conductor 3 is connected to two coil parts 3a, 3.
b and are connected so that their magnetic fluxes are generated in the same direction. And both coil parts 3
A portion of the Hall element 7 of the printed wiring board 12 on which the Hall element 7 and the amplifier section 11 are mounted is inserted between a and 3b. Note that the Hall element 7 is connected to the substrate 1.
2, and its lead wire is connected to printed wiring and connected to the input end of the amplifying section 11. Although the figure shows one set of coil parts 3a, 3b and one Hall element 7, for example, in the case of a three-phase AC circuit breaker, three Hall elements mounted on one board 12 are used. 7 are inserted into three sets of coil portions 3a and 3b formed by conductors 3 of each phase. 19 are coil parts 3a, 3b and Hall element 7
This is a case of a current sensor that houses an amplifier section 11 and an amplifier section 11. The opening/closing/closing section including the movable contact 4 and the fixed contact 5, the operating section including the tripping coil (not shown), the closing spring 14, the toggle link 15, and the handle 16 are the same as those of the conventional one. This explanation will be omitted.

When a current I flows through the main circuit conductor 3, a magnetic flux φ is generated that passes through a pair of coil portions 3a and 3b, as shown in FIG. Therefore, if this magnetic flux φ is made to pass perpendicularly to the surface of the Hall element 7 of the substrate 12 inserted between the pair of coil parts 3a and 3b, the Hall element 7 will generate a Hall voltage. When the current I exceeds a predetermined value, the Hall voltage also exceeds a predetermined value, which is amplified by the amplifying section 11 and energizes a tripping coil (not shown), tripping both latches 17 and 18, breaking the toggle link 15, and opening/closing the opening/closing section. cut off. The opening/closing section is re-closed by operating the handle 16 in the same manner as a conventional circuit breaker.

[Effect of idea]

According to the present invention, a coil part is formed on the main circuit conductor, and the Hall element part of the printed wiring board on which the Hall element is mounted together with the amplifier part is inserted into the coil part, so that there is no space between the Hall element and the amplifier part. The connection is mainly made by printed wiring, which has the advantage of reducing the trouble of connecting the two using thin lead wires, reducing the risk of wire breakage, and eliminating the need for a mounting board for the Hall element. Furthermore, since the magnetic flux density inside the coil section is high, there is no need to use an iron core, which has the effect of simplifying the configuration.

[Brief explanation of drawings]

1 and 2 show an embodiment of the circuit breaker according to the present invention, FIG. 1 is a side sectional view, FIG. 2 is an enlarged view showing a current sensor, and FIG. 3 is a conventional circuit breaker. FIG. 2 is a sectional view of main parts showing an example. 3... Main circuit conductor having a coil portion, 4... Movable contact, 5... Fixed contact, 7... Hall element, 11... Amplifying section, 12... Printed wiring board.

Claims (1)

[Scope of utility model registration request] A main circuit conductor, a Hall element that detects the current of this main circuit conductor, and an operation unit that amplifies the output of this Hall element and uses this output to perform a tripping operation of an opening/closing part connected to the main circuit conductor. In a circuit breaker equipped with an amplifier section, a coil section is formed on the main circuit conductor, and the Hall element and the amplifier section are mounted on the same printed wiring board, and the part of the printed wiring board on which the Hall element is mounted. A circuit breaker characterized in that: is inserted into the coil portion.