JPH0631698Y2 - Common mode choke coil - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a common mode choke coil for noise prevention suitable for mounting on a hybrid integrated circuit (hereinafter referred to as HIC).

[Conventional technology]

Conventionally, when connecting a noise-preventing common mode choke coil to a power line or a signal line (for example, a telephone line), another HIC-equipped device (for example, a surge absorber in the telephone line) is connected to these lines. However, it was installed separately from the device.

In the case of telephone lines, the common mode choke coil mounted on the insulating board was installed in the rosette or the switchboard.

[Problems to be solved by the invention]

In the structure in which the common mode choke coil and the HIC device are separately connected to the line, the number of parts is large, the required space is large, and it is difficult to place them spatially. ， There is a problem that the material cost becomes high.

An object of the present invention is to provide a noise-preventing common mode choke coil having a configuration suitable for HIC.

[Means for Solving Problems] In the common mode choke coil according to the present invention, a common mode choke coil element is made of a heat-resistant and solvent-resistant insulating material and a flat external connection electrode is attached to the bottom surface on the bottom surface. It is characterized in that the common mode choke coil element is housed in the recess of the base plate, and the recess is filled with a heat-resistant and solvent-resistant resin.

〔Example〕

FIG. 1 is an external view showing an embodiment of a common mode choke coil according to the present invention which is turned upside down, and FIG. 2 is an exploded perspective view of the same.

The coil element 4 is formed by winding the two windings 2 and 3 around the annular core 1 so that the magnetic fluxes generated in the respective windings cancel each other out.

The base plate 5 is made of an insulating material having heat resistance and solvent resistance, and has a coil element at the center of the bottom surface (upper surface in the figure) of a rectangular thick plate having a thickness dimension larger than the height of the coil element 4. A circular recess 6 that is slightly deeper than the height of 4 is formed. Further, on the bottom surface of the base plate 5, a step portion 7 that is shallower than the concave portion 6 is formed following the concave portion 6. The step portion 7 extends in parallel with one of the opposite side surfaces of the base plate 5 and slightly before the other opposite side wall.

Electrode plates 8 are provided at the four corners of the bottom surface of the base plate 5, respectively. As shown in FIG. 3, the electrode plate 8 integrally has a mounting portion 9 and a finger piece portion 11 which are bent in a U shape. The electrode plate 8 is attached to the base plate 5 by causing one of the leg portions of the attaching portion to be fitted into a narrow groove provided in the base plate 5 while the finger piece portion 11 is projected above the step portion 7. This is performed by bringing the other leg portion into contact with the side surface of the base plate 5.

Further, the coil element 4 is put into the recess 6 of the base plate 5, and the ends of the windings 2 and 3 are entangled with the constricted portion 12 of the finger piece 11 of the electrode plate 8 and connected by soldering. After that, the tips of the finger pieces 11 are folded inside the stepped portion 7 of the base plate 5. After that, the recess 6
Heat-resistant and solvent-resistant embedded resin 13 is injected into the stepped portion 7 to cover the coil element 4. Thus, the common mode choke coil for noise prevention as shown in FIG. 1 is obtained.

Since the bottom surface of the obtained choke coil is in the form of a flat package with an external connection electrode (that is, the electrode plate 8) attached, it is possible to perform connection processing in the same manner as an IC chip or chip capacitor. . That is, the electrode plate 8 has a shape suitable for surface mounting. In practice, the above choke coil is placed on an insulating substrate such as ceramic or glass having electrodes, paste solder is applied, and the electrode plate 8 is applied to the electrodes on the substrate by heating with far infrared rays of a reflow soldering device. By soldering, the desired connection can be made.

[Effect of device]

As described above, according to the present invention, surface mounting is performed in the same manner as an IC chip on a hybrid integrated circuit (HIC) in which a plurality of electronic components such as an IC chip are mounted and wired on an insulating substrate such as ceramic or glass. Compact and with noise prevention function
A common mode choke coil for noise prevention suitable for forming an HIC device is obtained.

Furthermore, since the electrodes have a shape suitable for surface mounting, they are thin,
Realization of miniaturization. In addition, since a base plate made of heat-resistant / solvent-resistant insulating material and a resin made of heat-resistant / solvent-resistant insulating material are used, the heat-resistant / solvent-resistant material is high on the whole and they are made of the same material. Therefore, heat stress applied during surface mounting can be prevented.

[Brief description of drawings]

FIG. 1 is an external view of an embodiment of the present invention which is turned upside down, FIG. 2 is an exploded perspective view of the same, and FIG. 3 shows an example of an electrode plate used in the embodiments of FIGS. It is a perspective view. 1; Annular core, 2, 3; Winding, 4; Coil element, 5; Base plate, 6; Recess, 7; Step, 8; Electrode plate, 9; Heat-resistant / solvent-resistant embedded resin.

Claims (1)

[Scope of utility model registration request] 1. A common mode choke coil element is housed in a recess of a base plate which is made of a heat-resistant / solvent-resistant insulating material and has a bottom surface on which a flat external connection electrode is additionally provided. A common mode choke coil characterized in that it is filled with a solvent resistant resin to cover the above common mode choke coil element.