JP3330452B2 - Current transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current transformer used as an alternating current detecting element in an overcurrent protection circuit for a switching power supply, a load current detection circuit for an air conditioner, and the like.

[0002]

2. Description of the Related Art FIG. 7 is a perspective view showing a bobbin structure of a conventional one-turn type current transformer. Conventionally, the structure of a current transformer having a primary conductor is such that a U-shaped conductor 1 in which a rod-shaped conductor as shown in FIG.
As shown in (b), a U-shaped conductor 1 as a primary winding is directly adhered to a flange 4 portion of a bobbin main body, which is a single member integrally formed of a synthetic resin, while leaving a terminal portion 2 at the tip. The U-shaped conductor 1 is mounted in the groove, or a groove having a thickness equal to that of the U-shaped conductor 1 is provided in the flange 4. Reference numeral 3 denotes a secondary winding pin terminal, and reference numeral 5 denotes a winding drum. FIG.
Shows a perspective view of the assembled current transformer, 6 is a secondary winding, 7 is a magnetic core, and 8 is a clamp for fixing the magnetic core. In the current transformer having such a conventional structure, the connection between the current circuit to be measured and the primary winding is performed by providing a circuit pattern corresponding to the magnitude of the current value to be measured on the substrate in advance, or as shown in FIG. As shown, an electric wire 10 provided with a crimp terminal 9 or the like at an end portion is used by penetrating a window of the magnetic core 7.

[0003]

Therefore, when a current transformer having the above-mentioned conventional structure is used by mounting it on a substrate, the conductor constituting the circuit pattern on the substrate is generally thin, so that the allowable current value is generally small. However, there is a problem that it cannot be used for measuring a large current. In such a case,
As shown in FIG. 9, the wire 10 serving as a primary winding is used by penetrating the window of the magnetic core 7. Therefore, there is a problem that the size of the current transformer becomes large.

The problem to be solved is that the current to be measured can be easily connected between the primary winding of the current transformer and the current circuit to be measured when the current to be measured is large and the current circuit to be measured cannot be provided on the substrate. To provide a transformer.

[0005]

In order to solve the above-mentioned problems, according to the present invention, conventionally, a primary winding is formed by forming a rod-shaped conductor into a U-shaped conductor and disposing the primary winding on a flange portion of a bobbin. On the other hand, the shape of the primary winding is H-shaped or I-shaped, and the primary winding is arranged on the flange portion of the bobbin, and the end of the primary winding is formed on the flange portion by using the flange portion of the bobbin. A connection terminal protrudes from an upper portion or a side portion, and a substrate fixing pin terminal protrudes from a lower portion of the flange portion, thereby facilitating connection with a current circuit to be measured. Also, the current transformer is mounted on a board connecting base plate having a terminal for connecting to the current circuit to be measured and a terminal insertion hole for the current transformer in advance, and then the primary winding and the measured wire are mounted on the board. Connection of the current circuit has been simplified. That is, the present invention includes at least two windings, and at least one of the windings has one turn. In the current transformer, the one-turn winding forms a bar-shaped conductor into an H shape, A current transformer characterized by being disposed on a synthetic resin bobbin flange,
A current transformer comprising at least two windings, at least one of the windings comprising one turn, the one turn winding penetrating an I-shaped rod-shaped conductor through a window of a magnetic core of the current transformer. A current transformer comprising at least two windings, wherein at least one of the windings has one turn, wherein the current transformer is disposed on a flange portion of a synthetic resin bobbin. The one-turn winding is a current transformer in which an I-shaped rod-shaped conductor is disposed in a collar of a synthetic resin bobbin so as to penetrate a window of a magnetic core of the current transformer. A current transformer, wherein at least one of the windings has one turn, wherein the one-turn winding is formed by molding a rod-shaped conductor into a U-shape, A current transformer arranged on a flange portion of the circuit board, having two fixed terminals for connecting the current transformer to a current circuit to be measured, and a terminal insertion hole for the current transformer connected to the terminal. A current transformer characterized by being attached to a base plate.

[0006]

In the case of measuring a large current in which the circuit pattern on the substrate on which the current transformer is mounted cannot be used, the end of the primary conductor is exposed at the top or side of the current transformer. Connection becomes easy. In addition, since the current transformer is mounted on the substrate mounting base plate having terminals connected to the primary winding in advance and then mounted on the substrate, connection with the current circuit to be measured is facilitated.

[0007]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view showing the structure of a bobbin of a current transformer according to a first embodiment of the present invention.
1A is a perspective view of an H-shaped conductor 1a formed by processing a rod-shaped conductor serving as a primary winding, and FIG. 1B is a perspective view of a bobbin having the H-shaped conductor 1a mounted on a flange 4 portion. It is. The terminal portion 2a is for connection between the H-shaped conductor 1a and the current circuit to be measured, and the terminal portion 2b at the lower end of the H-shaped conductor 1a is for reinforcement for fixing the current transformer to the substrate. The terminal unit 3 is a terminal for a secondary winding. FIG. 2 is a perspective view showing the configuration of the current transformer of the present invention. The terminal portion 2a is connected to the electric wire 10 connected to the current circuit to be measured by the crimp terminal 9a at the tip. In the current transformer of the present invention, if the current value to be measured is small and the current circuit to be measured can be constituted by a pattern on the circuit board, the terminal portion 2b can be used as a terminal of the primary winding. You can use both. Further, in the present embodiment, the H-shaped conductor is used, but the same effect can be obtained with the π-shaped conductor.

(Embodiment 2) FIG. 3 is a perspective view showing the structure of a bobbin according to Embodiment 2 of the current transformer of the present invention.
FIG. 3A is a perspective view of an I-shaped rod-shaped conductor 1b serving as a primary winding, and FIG. 3B is a perspective view of a bobbin having the I-shaped conductor 1b mounted on a flange 4 portion. The terminal portion 2c is for reinforcement for fixing the current transformer to the substrate. Terminal 3
Is a secondary winding terminal. FIG. 4 is a perspective view showing the configuration of the current transformer according to the present invention. After the current transformer is fixed to the substrate, the core portion at the tip of the electric wire 10 connected to both ends of the I-shaped conductor 1b and the current circuit to be measured. 9b is connected by soldering. In this embodiment, an I-shaped conductor is used. However, a similar effect can be obtained with a W-shaped conductor.

FIG. 5 is a perspective view showing a method of assembling a current transformer according to a third embodiment of the present invention. FIG.
Is of the conventional type with a U-shaped conductor 1. The current transformer is mounted on the board connecting base plate 11 to complete the current transformer. The resin base plate 11 has
An insertion hole 12 into which the terminal portion 3 of the secondary winding terminal is inserted;
There are an insertion hole 12a into which the terminal portion 2 of the U-shaped conductor 1 is inserted, and a terminal 13 connected to the current circuit to be measured.
3 is connected to the insertion hole 12a on the back surface of the base plate 11. FIG. 6 is a perspective view showing a state where the current transformer is mounted on the base plate 11. The terminal portion 2 and the terminal portion 3 are attached to a circuit board after being soldered on the back surface of the base plate 11,
The electric wire connected to the current circuit to be measured is connected to the terminal 13.

[0011]

As described above, the connection between the current circuit to be measured and the primary winding of the current transformer is facilitated, and the work efficiency of mounting the current transformer is improved. Also, measurement of a large current becomes possible.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a bobbin of a current transformer according to a first embodiment of the present invention. FIG. 1A is a perspective view of an H-shaped conductor serving as a primary winding. FIG. 1B is a perspective view showing a configuration of a bobbin equipped with the H-shaped conductor.

FIG. 2 is a perspective view illustrating a configuration of a current transformer according to the first embodiment of the present invention.

FIG. 3 is a perspective view illustrating a configuration of a bobbin of a current transformer according to a second embodiment of the present invention. FIG. 3A is a perspective view of an I-shaped conductor serving as a primary winding. FIG. 3B is a perspective view showing a configuration of a bobbin equipped with the I-shaped conductor.

FIG. 4 is a perspective view illustrating a configuration of a current transformer according to a second embodiment of the present invention.

FIG. 5 is a perspective view showing a method of assembling a current transformer according to a third embodiment of the present invention.

FIG. 6 is a perspective view illustrating a configuration of a current transformer according to a third embodiment of the present invention.

FIG. 7 is a perspective view showing a configuration of a bobbin of a conventional one-turn type current transformer. FIG. 7A is a perspective view of a U-shaped conductor serving as a primary winding. FIG. 7B is a perspective view showing a configuration of a bobbin equipped with the U-shaped conductor.

FIG. 8 is a perspective view showing a configuration of a conventional current transformer.

FIG. 9 is a perspective view in which a wire through which a current to be measured flows passes through a conventional current transformer.

[Signs in the drawings]

 DESCRIPTION OF SYMBOLS 1 U-shaped conductor 1a H-shaped conductor 1b I-shaped conductor 2 Terminal part (of U-shaped conductor) 2a, 2b Terminal part (of H-shaped conductor) 2c (for reinforcement) Terminal part 3 (for secondary winding) Terminal part 4 Flange 5 Winding frame 6 Secondary winding part 7 Magnetic core 8 Clamp 9 Crimp terminal 9a Core part (of electric wire) 10 Electric wire 11 Base plate 12, 12a Insertion hole 13 Terminal

Claims (3)

(57) [Claims] 1. A current transformer comprising at least two windings, wherein at least one of the windings has one turn, wherein the one-turn winding is formed by shaping a bar-shaped conductor into an H shape. A current transformer, wherein the current transformer is disposed on a flange portion of a resin bobbin. 2. A current transformer comprising at least two windings, wherein at least one of the windings has one turn, wherein the one-turn winding has an I-shaped rod-shaped conductor formed by a magnetic field of the current transformer. A current transformer, wherein the current transformer is disposed on a flange portion of a synthetic resin bobbin so as to pass through a window of a core. 3. A current transformer comprising at least two windings, wherein at least one of the windings has one turn, wherein the one-turn winding is formed by shaping a rod-shaped conductor into a U-shape. A current transformer disposed on a flange portion of a resin bobbin, the current transformer having two fixed terminals connected to a current circuit to be measured, and a terminal insertion hole for the current transformer connected to the terminal. A current transformer mounted on a base plate for connecting a substrate.