JPH0621217U - Wire wound chip inductor - Google Patents

Abstract

(57) [Summary] [Object] To provide a wire-wound chip inductor capable of preventing mold cracking during bending of a lead terminal after filling the mold. A magnetic coil 5 formed by winding a winding 6 on a magnetic core 5 is connected to a magnetic core 5, and both ends of the winding 6 have a pair of connecting portions 2a having lead terminal portions 1a and 1b, respectively. And 2b. Further, an opening is provided in each of the pair of lead terminal portions 1a and 1b, and
A resin mold is applied so as to cover the portions excluding a and 1b. Then, the lead terminal portions 1a and 1b are formed by bending the connection portions 2a and 2b at predetermined positions.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an inductance element and a transformer used for an electronic circuit, and more particularly to a wire-wound chip inductor used for high frequency and surface mounting.

[0002]

[Prior art]

 A conventional wire-wound chip inductor will be described with reference to FIG.

A magnetic coil 9 is formed by winding a winding 6 on a U-shaped magnetic core 5, and a pair of terminals 10 a and 10 b are fixedly attached to both sides of the magnetic core 5 where the winding 6 is not formed. To be done. The terminal 10a includes a lead terminal 1a and a terminal connecting portion 2a, and the terminal 10b includes a lead terminal 1b and a terminal connecting portion 2b. The ends of the winding 6 are connected to the terminal connecting portions 2a and 2b.

Further, the terminal connecting portions 2a and 2b are provided with holes for fixing the magnetic coil 9, and the core supporting pieces 3a and 3b for supporting a part of the side surface of the magnetic core 5 are inserted into the holes. It

Thereafter, resin molding is performed so as to cover the portions excluding the lead terminals 1a and 1b, that is, the magnetic coil 9 and the terminal connecting portions 2a and 2b, and then the lead terminals 1a and 1b are respectively attached to the terminal connecting portions 2a and 2b. It is manufactured by bending the magnetic core 5 side downward from a front end portion at a predetermined position and further bending from the bent portion toward the magnetic coil 9 at a predetermined position to form a lead terminal.

[0006]

[Problems to be solved by the device]

 However, it is unavoidable that the thickness of the resin mold applied to the outer periphery of the magnetic coil, leaving the lead terminals, becomes thinner as the size becomes smaller. This causes cracking, and there is a problem that it is difficult to obtain a low-cost wire-wound chip inductor in terms of manufacturing process and productivity.

[0007]

[Means for Solving the Problems]

 According to the present invention, it has a magnetic coil formed by winding a magnetic core, and a pair of connecting portions that are connected to the magnetic core and that have lead terminal portions. A wire-wound chip inductor that is connected to the pair of connecting portions and is resin-molded except for the lead terminal portions, wherein each of the pair of lead terminal portions has an opening portion. A wire-wound chip inductor having the above-mentioned resin mold is obtained.

Further, a wound chip inductor is obtained, which is characterized in that, after being filled with the resin mold, the lead terminal portion is formed by bending at a predetermined position of the connecting portion.

[0009]

[Action]

 In order to eliminate the drawbacks of the prior art, the present invention reduces the cross-sectional area of the terminal by reducing the bending resistance by providing a hole at the bent portion of the lead terminal. On the contrary, by forming a mold part on the contrary, the cross-sectional area of the mold is increased and the strength of the mold is increased to eliminate mold cracking, improve the production capacity, and provide a low-cost wire-wound chip inductor. It is what you do.

[0010]

【Example】

 An embodiment of the present invention will be described with reference to FIG.

In FIG. 1, terminals 10a and 10b are adhesively fixed to a magnetic coil 9 formed by winding a winding 6 on a U-shaped magnetic core 5 as in FIG. The terminals 10a and 10b are composed of a lead terminal 1a, a terminal connecting portion 2a, a lead terminal 1b, and a terminal connecting portion 2b, respectively. The lead terminals 1a and 1b are respectively bent as in FIG. 3, and the bent portions of the lead terminals 1a and 1b are bent. Through holes 4a and 4b are provided in the vicinity.

Further, similarly to FIG. 3, the terminal connecting portions 2a and 2b are provided with holes for fixing the magnetic coil 9, and the core supporting pieces 3a and 3b are inserted into the holes. After that, a resin mold is filled so as to cover the magnetic coil 9 and the terminal connecting portions 2a and 2b including the through holes 4a and 4b to form the wound chip inductor of the present invention.

By forming a resin mold portion in the through holes 4a and 4b, the cross-sectional area of the mold is increased, and the strength of the mold is increased, whereby mold cracks can be eliminated.

Further, by providing the through holes 4a and 4b, when the lead terminals 1a and 1b are bent, the drag force generated at the bent portions can be reduced, and mold cracking is prevented in the bending work after resin molding. be able to.

2 (a) and 2 (b) respectively show a wire-wound chip inductor having a through hole (specifically, an inductor as shown in FIG. 1) and a winding having no through hole. A predetermined number of wire chip inductors (specifically, inductors as shown in FIG. 3) are prepared, and in all of them, the resistance to bending of the lead terminals 1a and 2a and the molding to the pulling of the lead terminals 1a and 2a. It is the figure which measured the intensity | strength of.

From the data of FIG. 2A, it is understood that the bending resistance is lower when the through holes 4a and 4b are provided than when the through holes 4a and 4b are not provided. Also, from the data of FIG. 2 (b), it can be seen that the strength of the mold with respect to the pulling of the terminal is better than that without the through holes 4a and 4b. That is, it is understood that by providing the through holes 4a and 4b in the lead terminals 1a and 2a, the strength of the mold is increased and cracks in the mold can be eliminated.

In the embodiment, the U-shaped magnetic core is shown. However, the magnetic core is not limited to the U-shaped, and the same effect can be obtained with a hollow core or the like.

[0018]

[Effect of device]

 According to the present invention, by providing the through hole in the lead terminal, the resistance to bending of the lead terminal can be reduced, the strength of the mold against pulling can be increased, and the productivity can be improved, and the winding cost can be reduced. A wire chip inductor can be provided.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a wire wound chip inductor according to the present invention.

FIG. 2 (a) is a diagram showing the drag force of the lead terminal with respect to the number to be tested when the lead terminal is bent in the wire-wound chip inductor of the present invention, and FIG. 5 is a graph showing the results of measuring the strength of the mold.

FIG. 3 is a perspective view showing an embodiment of a conventional wire-wound chip inductor.

[Explanation of symbols]

 1a, 1b Lead terminal 2a, 2b Terminal connection part 3a, 3b Core support piece 4a, 4b Through hole 5 Magnetic core 6 Winding (coil) 7a, 7b Coil terminal 8 Mold part 9 Magnetic coil 10a, 10b Terminal part

Claims (2)

[Scope of utility model registration request] 1. A magnetic coil, comprising: a magnetic coil formed by winding a magnetic core; and a pair of connecting portions that are connected to the magnetic core and have lead terminal portions. In a wire-wound chip inductor connected to a pair of connecting portions and resin-molded except for the lead terminal portions, an opening portion is provided in each of the pair of lead terminal portions, and the opening portion is the resin portion. A wire-wound chip inductor formed so as to be molded. 2. The winding chip inductor according to claim 1, wherein the lead terminal portion is bent at a predetermined position of the connection portion after being filled with the resin mold. Chip inductor.