JPH0631111U - Substrate type noise filter - Google Patents

Abstract

(57) [Abstract] [Purpose] A common mode choke coil using a square-shaped core sized along the outer periphery of the wiring board and a noise component mounted in the central hole of the common mode choke coil to increase the current capacity, A board-type noise filter that can be automated in manufacturing and assembly. [Structure] A large number of pin terminal portions 16 are integrally formed at intervals on the outer periphery and inner peripheral edge of the opening end of the double-sided tubular body having an opening on the bottom surface, and a special resin 19 is formed on the outer side of the double-sided tubular body. A strip-shaped core 14 is housed in an insulating cover 15 having a conductor 17 which extends to the pin terminal portion 16 in a strip shape at intervals on the surface in the circumferential direction and has an exposed surface subjected to electroless plating. The common terminal choke coil is formed by connecting the pin terminal portion to the through-angle hole 8 with and capacitors 3 and 5 are mounted in the central hole of the insulating cover.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a substrate type noise filter in which a filter element including a choke coil using a closed magnetic circuit core and a faston tab are mounted on a wiring substrate.

[0002]

[Prior art]

 A conventional example of the substrate type noise filter is shown in a plan view in FIG. In FIG. 4, a wiring board (hereinafter referred to as a board) 1 is provided with wiring conductors (not shown) forming a noise filter circuit on the bottom surface. A fast tab 2 bent into an L shape is inserted from below into a square hole formed along the short side of the substrate 1. An interline capacitor 3, a toroidal common mode choke coil 4 (hereinafter referred to as a coil), and a line earth capacitor 5 are mounted on a substrate 1. The coil 4 is obtained by housing the toroidal core in an insulating case having a central partition plate and winding two windings 6 through each of the two divided central holes of the toroidal core. is there.

[0003]

[Problems to be solved by the device]

 In the conventional noise filter described above, since the filter elements are arranged on the substrate 1 having a predetermined size as shown in FIG. 4, the usable toroidal core is small, the rated current is less than 3 A, and the application field is narrow. was there. In addition, the coil 4 has a drawback that it is difficult to automate the winding operation and the productivity is low because it is done manually, and it is difficult to draw the end of the winding into a fixed arrangement, so that it cannot be efficiently mounted on the substrate. was there.

[0004]

[Means for Solving the Problems]

 In addition to using a square-shaped core whose external shape is close to that of the wiring board, the winding is composed of the wiring conductor of the board and the conductor provided on the outer surface of the insulating cover. The insulating cover is a double-sided cylindrical body with a large number of pin terminals integrally projecting on the opening on the bottom surface.It is made of ordinary resin and conductive special plating adhesive resin. The resin is exposed on the outer surface of the double cylinder at intervals in the circumferential direction, is exposed by being connected to the pin terminals, and a conductor is provided on the exposed surface by electroless plating. Put the insulation cover on the square-shaped core and insert the pin terminals into the board. Noise filter parts other than the coil are mounted on the board in the center hole of the coil.

That is, the present invention is a board-type noise filter in which a filter element is mounted on a wiring board provided with an input terminal, and the choke coil has an opening on the bottom surface made of a normal resin and a special resin having a plating adhesion property. A double-sided cylinder is molded with a large number of pin terminals that are integrally projected at intervals on the outer and inner peripheral edges of the open end, and a special resin is circumferentially applied to the outer surface of the double-angled cylinder. Insulation cover consisting of a double-sided cylinder and the back surface of the wiring board, which are strip-shaped at intervals and extend to the pin terminals to expose them, and the exposed surface is electroless plated to form conductors on the surface. A coil was formed with the wiring conductor formed in the above, and the above-mentioned insulating cover was put on the square-shaped core and mounted on the substrate.It was confirmed that filter elements other than the choke coil were mounted in the central hole of the square-shaped core. Characteristic board type It is an is filter.

[0006]

[Action]

 By using a square-shaped core whose dimensions are close to the outer diameter of the board, the space for mounting the filter element other than the coil is secured in the center of the board, increasing the rated current value. The insulating cover houses the square core and holds it on the board to insulate the square core from the conductor and form the winding.

[0007]

【Example】

 An embodiment of the substrate type noise filter according to the present invention will be described with reference to the drawings. FIG. 1 is an external perspective view of a substrate type noise filter according to the present invention. FIG. 2 shows an exploded perspective view of the substrate type noise filter shown in FIG. The wiring board 7 has the same dimensions as the wiring board 1 shown in FIG. 4, and the faston tabs 2 are inserted along the short sides in the same manner as the wiring board 1. The capacitors 3 and 5 are attached to the central portion of the wiring board 7. A large number of through-angle holes 8 are formed in the peripheral portion of the wiring board 7 at positions corresponding to the conductors 17 formed on the surface of the insulating cover 15 so as to form a double rectangular coil with each other. A wiring conductor diagram on the bottom surface of the wiring board 7 is shown in FIG. In FIG. 3, the large circular portion 9 is a portion to be brought into contact with the L-shaped horizontal portion (not shown) of the faston tab 2 mounted on the substrate surface, and the wiring conductors 10, 11, 12 connected to the circular portion 9 are It is a conductor for forming a filter circuit. The wiring conductors 13 (12 in the figure) that surround the through-angle holes 8 and connect the inner through-angle holes 8 and the adjacent outer through-angle holes 8 are conductors for winding.

The square-shaped core (hereinafter referred to as the core) 14 has the same cross-sectional shape and dimensions as the toroidal core of the coil 4 shown in FIG. 4, and has a magnetic path length of about twice. The insulating cover 15 is a heat-resistant resin that can be dipped in a rice field tank, is a double-sided cylindrical body with an open bottom that can be covered with the core 14, and has through-holes at the inner and outer peripheral edges of the open end surface. The prismatic pin terminal portions 16 to be fitted in 8 are integrally projected in an array corresponding to the through-angled holes 8. On the outer surface of the insulating cover 15, conductors 17 for windings are provided in a strip shape at intervals in the circumferential direction, and the conductors 17 extend to the bottom surfaces of the corresponding inner and outer peripheral pin terminal portions 16. For the conductor 17, first, a shallow groove is provided on the outer surface portion of the ordinary resin 18 on which the conductor 17 is provided, and up to the pin terminal portion 16, a primary molded body having a projection continuing to the groove bottom of the shallow groove is formed, and then The shallow groove is filled with a special resin 19 having a plating adhesion property, and then the outer surface and the bottom surface of the projecting piece are covered to finish the outer shape insulating cover (secondary molded body) 15 shown in FIG. It is a plated conductor formed by immersing the body in electroless plating and forming it on the exposed surface of the special resin 19.

A double-sided adhesive tape (not shown) is attached to the top surface of the core 14, and then the core 14 is covered with an insulating cover 15 to push up the core 14 to fix the core 14 to the insulating cover 15. 1 and the core 14 is covered with the insulating cover 15, the pin terminal portion 16 is inserted into the through-angled hole 8 of the wiring board 7, and the insulating cover 15 is attached to the wiring board 7. The common mode choke coil shown is formed. The wiring board 7 is dipped in a solder bath to solder the wiring conductors 10 to 13 at once. The wiring conductor 13 and the conductor 17 form a winding (two windings with a winding number of 6 in the figure), and the substrate type noise filter in which the common mode choke coil 20 is mounted on the substrate is completed.

[0010]

[Effect of device]

 According to the present invention, since a larger square-shaped core is used than before, the rated current is increased, and the effect of forming a line filter with a large current capacity can be obtained. Since it is configured so that it can be easily mounted and immersed in the solder bath once, the automation rate can be increased and the effect of a substrate type noise filter with improved productivity can be obtained.

[Brief description of drawings]

FIG. 1 is an external perspective view showing an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the substrate type noise filter shown in FIG. 1, showing an embodiment of the present invention.

FIG. 3 is a bottom view of the wiring board in FIGS. 1 and 2.

FIG. 4 is a plan view showing a conventional example.

[Explanation of symbols]

 1,7 Wiring board 2 Faston tab 3,5 Capacitor 4 Toroidal common mode choke coil 6 Winding 8 Through-angle hole 9 Circular part 10, 11, 12, 13 Wiring conductor 14 R-shaped core 15 Insulation cover 16 Pin terminal part 17 Conductor 18 resin 19 special resin 20 common mode choke coil

Claims (1)

[Scope of utility model registration request] 1. A board-type noise filter comprising a wiring board provided with an input terminal and a filter element mounted on the choke coil, wherein the choke coil is a double-sided square with an opening on the bottom made of a normal resin and a special resin having a plating adhesion property. The cylindrical body is molded with a large number of pin terminal parts integrally projected at intervals on the outer and inner peripheral edges of the open end, and a special resin is circumferentially spaced on the outer surface of the double-sided cylindrical body. Formed on the back surface of the wiring board and an insulating cover consisting of a double-sided cylinder that is placed in a strip shape and extends to the pin terminals to expose it, and the exposed surface is electroless plated to form a conductor on the surface. A coil is formed by a wiring conductor, the insulating cover is covered on a square-shaped core and mounted on a substrate, and a filter element other than a choke coil is mounted in a central hole of the square-shaped core. Type noise filter.