JPH081868B2 - Current transformer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a current transformer for detecting an eddy current, such as an eddy current relay used in a circuit breaker for wiring.

[Prior art and its problems]

In the current transformer, generally, as shown in FIG. 4, electric iron plates are laminated to assemble a quadrilateral closed magnetic circuit core 1 to form a rectangular window 2. Secondary coils 3 and 4 are respectively wound around the sides of the iron core 1 that form a pair of opposite sides, and both coils 3 and 4 are wound. The coils 3 and 4 are respectively wound. One lead wire 3a, 4a is connected by a crimping terminal 5 and connected in series, and each other lead wire 3b, 4b is drawn long and connected to a load such as a relay via a rectifier (not shown). There is. A main circuit conductor (primary conductor) 6 penetrates the window 2 of the iron core 1. Of course, if the magnetic coupling between the primary conductor and the secondary coil may be coarse, 1 is provided on one side of the iron core 1.
In some cases, only one coil may be wound. Reference numeral 7 is a support fitting of this current transformer. When the primary current to be detected flows through the main circuit conductor 6, a secondary current proportional to this current is generated and both secondary coils 3, 4
Flow through the rectifier to the load, and the secondary current detects the eddy current on the primary side.

By the way, in this type of current transformer, when the secondary coil is divided into two, the insulation film at the end of one of the lead wires of both coils is removed, and an insulation sleeve is inserted to connect with a crimping terminal. There was such a trouble. When used in a three-phase circuit, the length up to the burden on each phase current transformer is different, and both coils must be prepared in various ways according to the length of the other lead wire. There was a drawback.

[Object of the Invention]

It is an object of the present invention to provide a current transformer that can simplify the assembly force, the process, and the parts management in the case of mass production.

[Main points of the invention]

According to the present invention, a secondary coil is wound around both or one of the sides of an iron core forming a pair of opposite sides of a quadrilateral closed magnetic circuit core having a window at the center, and the primary conductor is inserted through the window. In the current transformer, a printed circuit board is provided between one of the sides of the pair of opposing sides of the closed magnetic circuit core and one end of the secondary coil, and a connector is provided on the printed circuit board. The lead wire of the secondary coil is connected to a printed wiring on the printed circuit board, two secondary coils are connected in series via this wiring, or is connected to a connector. The two coils are connected in series by simply inserting the lead wire into the through hole of the printed circuit board and connecting it, or by connecting with the connector to complete the connection of the current transformer. If a rectifying element is mounted on the printed board, this rectifying element can be connected at the same time.

Example of Invention

An embodiment of the present invention will be described in detail with reference to FIGS. In FIG. 1, the current transformer is similar to the conventional one in that an iron core 1 having a window 2, secondary coils 3 and 4 wound around opposite iron core sides of the iron core 1, and a main member penetrating the window 2 are provided. One side of each of the secondary coils 3 and 4 wound around opposite sides of the iron core 1 and one side of the other side of the iron core 1 which is composed of the circuit conductor 6 and the like. The point that the printed circuit board 8 is sandwiched between and is greatly different from the conventional one. Reference numeral 9 is a spacer inserted between the printed board 8 and the iron core 1. As shown in FIG. 2, this printed circuit board 8 has through holes 8a, 8b for inserting the core sides of the core side of the secondary coil of the core 1 on which the secondary coil is wound, and the lead wires of the secondary coil. A through hole 4c to be inserted is provided, and a printed wiring 10 for connecting the through hole 4c and a member mounted on the printed board 8 is provided. Reference numeral 11 is a connector that connects the printed circuit board 8 and other external circuits, and 12 is a rectifying element that rectifies the current in the secondary coils 3 and 4. When such a printed circuit board 8 is provided, as shown in FIG. 3, the length L of the lead wires 3 and 3B of the secondary coil 3 is equal to the distance between the end surface of the secondary coil 3 and the printed circuit board 8. Therefore, it can be shortened. Of course, the same applies to the secondary coil 4, and the length L of the lead wire is the same for both coils 3 and 4.
Can be unified. Further, connection with an external circuit can be easily made with the connector 11.

〔The invention's effect〕

As described above, according to the present invention, since the current transformer is provided with the printed board on which the connector and the rectifying element are mounted between the end face of the secondary coil and the iron core, the lead wire of the secondary coil is It suffices to insert it into the through hole of the printed circuit board and connect it, and the length of the lead wire is short and unified to the same length, and it is possible to connect easily. In addition, the current of the secondary coil is rectified by the rectifying element mounted on the printed circuit board, and the connection with the external circuit can be done with the connector. The coil can be managed, the current transformer can be assembled, and the handling is simple and effective. Is big.

[Brief description of drawings]

FIG. 1 is a front view of a current transformer according to the present invention, FIGS. 2 and 3 show some of the components of this current transformer, FIG. 2 is a plan view of a printed circuit board, and FIG. 3 is a secondary view. The coil front view and FIG. 4 are front views of a conventional current transformer. 1: Iron core, 3, 4: Secondary coil, 8: Printed circuit board, 10: Printed wiring, 11: Connector, 12: Rectifying element.

Claims (2)

[Claims] 1. A quadrilateral closed magnetic circuit core having a window at the center, a secondary coil is wound around both or one of the core sides that form a pair of opposing sides, and the primary conductor is inserted through the window. In the current transformer, the printed circuit board is provided between one of the core sides forming the other pair of opposing sides of the closed magnetic circuit core and one end of the secondary coil, and a connector is provided on the printed circuit board. A current transformer characterized in that the lead wire of the secondary coil is connected to the connector via a wiring on the printed circuit board. 2. The current transformer according to claim 1, wherein a rectifying element for rectifying the output current of the secondary coil is mounted and connected to the printed circuit board.