JPH0737288Y2 - Inductor - Google Patents

Description

[Detailed Description of Device] a. Purpose of the Invention [Industrial field of application] The present invention inserts two magnetic legs of a split core having square magnetic legs into a cylindrical winding core of a winding frame and butts them together to form a closed magnetic circuit. The present invention relates to an inductor having a core.

[Prior Art] A conventional inductor using a UU-type or EE-type split-type closed magnetic circuit core having a square-shaped magnetic leg has a magnetic leg in the tubular core of a winding frame with the required windings. Insert it, butt it, and hold it in the closed magnetic circuit with a U-shaped tightening tool such as a U-shaped tightening tool or insulating tape.
The closed magnetic circuit core is fixed to the winding frame and the fastening member is fixed to the closed magnetic circuit core by applying the adhesive to the main part or immersing the adhesive in the impregnating agent.

For example, in the case of an inductor for noise prevention, as shown in FIG. 4, a winding 2 is applied to a winding frame 1 with pin terminals having flanges at both ends and in the middle of a cylindrical winding core, and a U-shaped split core 3 Two
One of the magnetic legs 31 is inserted into the cylindrical winding core of the winding frame 1 and is butt-shaped to form a closed magnetic circuit core, and the U-shaped tightening fitting 4 covers the outer surface of the other magnetic leg 31. Also, the claws 41 at both ends are elastically contacted with the outer surface of the body of the closed magnetic circuit core (hereinafter referred to as the core), and the tightening metal fitting 4 is attached to the core. The adhesive 5 was applied over the entire area, and the adhesive 5 was applied in the gap between the base of one of the claws 4 (right side in the figure) of the tightening fitting 4 and the outer surface of the core body to fix them together. .

[Problems to be solved by the device]

When an adhesive is used, it is troublesome to handle, and at least two places shown in FIG. 4 or two places for fixing the closed magnetic circuit cores to the bobbin 1 (one is shown by a dotted line), a total of three places. Since it is necessary to apply the adhesive, there is a problem that the required man-hours are large, and that when the adhesive is applied to the tightening fitting 4, the adhesive flows into the abutting surfaces due to a capillary phenomenon to reduce the inductance.

Further, when the impregnating agent is used, there are problems that expensive equipment including discharge of the impregnating agent vapor is required and that the inductance is lowered due to the penetration of the impregnating agent into the abutting surfaces.

B. Configuration of the Invention [Means for Solving the Problem] The present invention inserts two magnetic cores each having a rectangular cross section of a split core into a cylindrical core of a wound winding frame. In an inductor that is abutted against each other and held in a closed magnetic circuit by a tightening member, leaf springs made of a unidirectional shape memory alloy material are inserted in the cylindrical winding core and the magnetic legs are elastically contacted. Is an inductor.

[Action]

The shape memory alloy leaf spring becomes irreversibly curved by heating, and as a leaf spring material, it makes elastic contact with the magnetic leg and the inner wall of the cylindrical core (hereinafter referred to as core), and the magnetic leg is attached to the inner wall of the core. Press to secure the core to the bobbin.

〔Example〕

FIG. 1 is a vertical sectional front view showing an embodiment of the present invention, in which the same parts as those in FIG. 4 are designated by the same reference numerals. In the figure, a leaf spring 6 made of a unidirectional shape memory alloy elastically contacts the winding core and the magnetic leg 31 with a length slightly shorter than the length of the tubular winding core (hereinafter, winding core) of the winding frame 1. There is.

The shape memory alloy is an alloy having a shape memory effect, and many types such as nickel-titanium alloys and copper alloys are known. The shape memory effect of these alloys is that when a metal material in a low temperature (generally room temperature) state is heated above a certain temperature (higher than room temperature, for example, 50 ° C) after deformation, the original metal material before deformation The irreversible phenomenon, which is the phenomenon of returning to the shape and the original shape after cooling, is called the unidirectional shape memory effect.

The inner dimension (the vertical dimension in the figure) of the winding core 1 of the winding frame 1 in FIG. 1 is sufficiently larger than the dimension of the magnetic leg 31, and the leaf spring 6 has an outer surface of the magnetic leg 31 and an inner wall of the winding core (inner dimension in the figure). The bottom) is selected for the elastic contact.

In the exploded view of FIG. 3 (inverted top and bottom from FIG. 1, the windings and the clamps are omitted), the leaf spring 6 is a one-way shape memory previously stored in a spring-like shape indicated by a broken line. FIG. 2 is a vertical cross-sectional front view of the inductor in which the alloy is transformed into a flat plate (solid line) at low temperature, and the leaf spring 6 transformed into the flat plate is loosely inserted in the winding core. In addition, the deformation of the leaf spring 6 at a low temperature may be an arc shape such that it is lightly press-fitted between the outer surface of the magnetic leg 31 and the inner wall of the core instead of the flat plate. You may intervene. When the leaf spring 6 is heated (for example, 50 ° C.) and returns to the original memory shape, a curved portion is formed between the outer surface (or inner surface) of the magnetic leg 31 and the inner wall of the winding core in the winding frame 1 as shown in FIG. Is flattened so that the magnetic legs 31 are elastically contacted.

In the state shown in FIG. 2, when the leaf spring 6 is heated to a temperature higher than a required temperature (for example, 50 ° C.) by an appropriate means, as shown in FIG. 1, the leaf spring 6 is closed by two split cores 3. The weight of the road core (hereinafter referred to as the core) and the fastening metal 4 is overcome to restore the memory shape (shown by the broken line in FIG. 3) to lift the core, and the curved portion elastically contacts the outer surface of the magnetic leg 31 to cause the magnetic leg 31 to move. The inner surface of is pressed against the inner wall of the upper part of the winding core to become substantially flat, and the core held in the closed magnetic circuit by the tightening metal fitting 4 is tightly fixed to the winding frame 1.
If the core is fixed and does not move, it is not necessary to fix the core and the bobbin 1 with an adhesive. Similarly, there is no fear that the fastening member 4 will come off the core, and therefore it is not necessary to fix the fastening member 4 to the core with an adhesive or an impregnating agent.

C. Effect of the Invention According to the present invention, since the inductor has a structure in which the leaf spring made of a unidirectional shape memory alloy is inserted into the winding core and the core is fixed to the winding frame, the assembling work is easy and the man-hours are small. As a result, no special equipment is required, and the dimensional tolerance of the magnetic leg and the dimensional tolerance of the winding core can be relaxed as compared with the conventional ones, so there is an advantage that it is cheaper, and adhesives and impregnation agents can be omitted. The advantage is that the gap between the butted surfaces of the core does not change, and therefore stable inductance can be realized.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing an inductor according to an embodiment of the present invention. FIG. 2 is a vertical cross-sectional front view showing a state in which a leaf spring deformed into a flat plate at a low temperature is inserted in the inductor of FIG. FIG. 3 is an exploded perspective view showing the inductor of FIG. 2 by turning it upside down and omitting a part thereof. FIG. 4 is a front view showing a conventional inductor. DESCRIPTION OF SYMBOLS 1 ... Reel, 2 ... Winding, 3 ... Split core, 31 ... Magnetic leg, 4 ... Tightening metal fitting, 41 ... Claw, 5 ... Adhesive agent, 6 ... Leaf spring.

Claims (1)

[Scope of utility model registration request] 1. A pair of two magnetic legs each having a rectangular cross section of a split core are inserted into a cylindrical winding core of a wound winding frame, and the two magnetic legs are butted against each other and held in a closed magnetic circuit by a tightening member. In the inductor described above, a leaf spring made of a unidirectional shape memory alloy material is inserted into the cylindrical winding core, and the core of the winding core facing the leaf spring contact surface of the inner wall of the winding core is inserted. In the direction of the inner wall,
An inductor characterized in that the magnetic legs are elastically fixed.