JPH06310357A - Manufacture of inductor - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Automates the assembly work of inductors in which strip-shaped terminals are led out from a pair of lead-out grooves using a pot-shaped core and a flat-plate core. [Structure] A step of insert-molding a rectangular insulating pedestal 1 having a central through hole 6 in a lead frame 2 having five pairs of strip-shaped terminals 3, and a square fitting step connected to a pair of lead-out grooves on an opening surface. Step of covering the pot-shaped core provided on the rectangular insulating pedestal 1 with the cylindrical winding 8 provided concentrically with the central through hole 6 and fitting the rectangular insulating pedestal 1 on the fitting step and mounting it on the lead frame 2. And a flat plate core 14 having a square fitting concave portion surrounding the central protruding portion corresponding to the center of the pot-shaped core 9 on one surface, and an adhesive is applied to the central protruding portion to form a rectangular insulating pedestal 1 in the fitting concave portion. Is fitted to the lead frame 2 from below, and the pot-shaped core 9 and the flat plate core 14 are bonded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an inductor in which a strip-shaped terminal is led out from a lead-out groove by using a pot-shaped core having a pair of lead-out grooves and a flat plate core.

[0002]

2. Description of the Related Art An end portion of a winding housed in a closed magnetic circuit core composed of a pot-shaped core and a flat-plate core is connected to a strip-shaped terminal, and the strip-shaped terminal (hereinafter referred to as a terminal) is led out to a pair of pot-shaped cores. In the conventional inductor derived from, the tip of the pair of strip-shaped terminals of the lead frame is fixed with an insulating adhesive in the lead-out groove so that it does not come into contact with the groove bottom and the groove wall, and the cylindrical winding is potted. Put the wire into the recess of the shaped core and connect the end of the winding to the terminal in the lead-out groove by spot welding, cover the spot welded connection with an insulating adhesive, and bond it to the end face of the core of the pot-shaped core. Apply the agent and place the flat plate core on the pot core, or invert the lead frame and pot core on the flat core, clamp them together, and then separate them from the lead frame. It was being done.

[0003]

As described above, in the conventional inductor, there is no portion that serves as a reference for assembling the terminal of the pot-shaped core and the lead frame, and it is difficult to control the thickness of the adhesive layer. Since there is a problem that insulation failure may occur and the pot-shaped core and the flat plate core are joined by contour matching, there is a problem that misalignment may occur, assembly work is troublesome, and the inductor manufacturing process should be automated. There was a problem that it was difficult.

[0004]

SUMMARY OF THE INVENTION According to the present invention, a lead frame having a plurality of pairs of strip-shaped terminals is insert-molded with a rectangular insulating pedestal having a central through hole in the terminals protruding from opposite side surfaces. , A vase-shaped core with a pair of lead-out grooves concentric with the center and a square fitting step corresponding to a rectangular insulating pedestal (hereinafter referred to as pedestal) on the joint surface with the flat core (Hereinafter referred to as a through hole.) Cover the cylindrical winding concentrically with the pedestal, fit the pedestal into the fitting step of the pot core, and loosely fit the terminal into the lead-out groove of the pot core to attach it to the lead frame. Assembling from above, and a flat plate on one side of which a central protrusion corresponding to the core of the pot-shaped core and a rectangular fitting recess concentric with the central protrusion (hereinafter referred to as “protrusion”) corresponding to the pedestal are provided. After applying the adhesive to the core and the protrusion, fit the pedestal into the fitting recess and insert it into the lead frame from below. Put viewed, characterized in that it comprises a step of bonding the pot-shaped core and the flat core.

That is, the present invention is a method of manufacturing an inductor in which strip terminals are led outwardly from opposite side walls of a closed magnetic circuit core composed of a pot core and a flat plate core, and a plurality of pairs of strip terminals are provided. A step of insert-molding a rectangular insulating pedestal having a buried central through hole by projecting the tips of the pair of strip-shaped terminals from the central portions of the opposite side surfaces on the lead frame, and a square fitting step facing the rectangular insulating pedestal. Insert the core of the pot-shaped core, which is concentric with the core and connected to the pair of lead-out grooves, into the cylindrical winding that is concentric with the central through hole on the rectangular insulating pedestal, and cover it. Part and the rectangular insulating pedestal are fitted together and assembled to the lead frame, and a flat plate is provided on one side with a central protrusion facing the center of the pot-shaped core and a concentric rectangular fitting recess corresponding to the rectangular insulating pedestal. Apply adhesive to the core and the central protrusion. A fitting recess fitted an insulating pedestal is an inductor manufacturing method which comprises a step of bonding a pot-shaped core and the plate-core assembled from below the lead frame.

[0006]

[Function] A rectangular insulating pedestal integrally molded with the tip of the strip terminal extending from the lead frame to the center provides electrical insulation, mechanical connection and positioning between the opposing strip terminals, and the center is provided in the center. The through hole can be inserted through the winding shaft to form a tubular winding on the lead frame together with the barb pin inserted through the circular hole of the frame portion. Further, the rectangular insulating pedestal is positioned by the fitting step of the pot-shaped core and the fitting recess of the flat-plate core, and the strip-shaped terminal can be led out to the outside of the pot-shaped core and the flat-plate core from the middle of the height of the lead-out groove.

[0007]

1 (a) to 1 (d) are external perspective views for explaining the steps of one embodiment of a method of manufacturing an inductor according to the present invention. FIG. 1A shows a step of providing a lead frame 2 with a rectangular insulating pedestal 1 by insert molding. The lead frame 2 is formed by punching a plurality of H-shaped (five in the figure) H-shaped rectangular metal plates at a constant interval along the lengthwise direction of a thin rectangular metal plate made of a material having good electrical conductivity, and forming five pairs of strip-shaped terminals 3 ( In the drawing, one set is shown in a punched state), the outer shapes of the frame portions 4 on both sides are square, and a circular hole 5 is punched inside. The circular hole 5 is used for positioning the lead frame 2 and also serves as a protruding hole for a sling pin that twists the winding start and winding end when forming the cylindrical winding on the rectangular insulating pedestal 1. . A pair of terminals 3 facing each other with a gap between them
Insulation resin is insert-molded in a shape to connect the two, and the rectangular insulation pedestal 1 (in the figure, 4 sets out of 5 sets) are integrally formed on the lead frame 2.

As shown in the enlarged partial view of the lead frame 2 in FIG. 2, the rectangular insulating pedestal 1 is a rectangular plate having a central through hole (hereinafter referred to as a through hole) 6 in the center thereof, and is provided at the center of the opposite side surfaces. The tips of the pair of terminals 3 are embedded, and a circular step portion 7 is provided on the bottom surface along the peripheral edge of the through hole 6.

The next step is shown in FIGS. 1 (b) and 1 (c). Cylindrical winding 8 of a predetermined size on the pedestal 1 of the lead frame 2
The end portion of the winding [not shown in FIG. 1B] is placed on the terminal 3 near the pedestal 1 by spot welding, etc. To connect. Figure 1
(B) shows this stage. Subsequently, the potted core 9 is attached to the lead frame with the joining surface facing the flat plate core forming the set facing down and the lead-out groove 10 corresponding to the terminal 3 covering the cylindrical winding 8 and the pedestal 1.

As shown in FIG. 3, the pot-shaped core 9 has a rectangular parallelepiped outer shape and has a rectangular joint surface with a pair of flat-plate cores, a cylindrical core 11, an annular storage recess 12, It has a pair of shallow lead-out grooves 10 in the central portion of the short sides, and a fitting step portion 13 circumscribing a storage recess 12 having the same depth as the lead-out groove 10. The thickness dimension of the pedestal 1 is set to be slightly larger than the depth of the fitting step portion 13 and slightly smaller than the total depth of the fitting recessed portions 16 of the flat plate core that forms a pair with the fitting step portion 13 and the pot-shaped core. To be done.

As shown in FIG. 1 (c), the pedestal 1 is fitted into and abuts on the fitting step portion 13 in a state where the pot-shaped core 9 is assembled, so that the pedestal 1 is slightly smaller than the joint surface of the pot-shaped core 9. It projects downward. FIG. 4 shows a flat plate core 14 joined to the pot core 9. The flat plate core 14 has a diameter slightly larger than the center core 11 of the pot-shaped core 9, and has a central projection 15 that is loosely fitted in the circular step 7 of the pedestal 1 and the same as the fitting step 13 concentrically with the projection 15. The fitting recess 16 having a size is provided on one surface.

An adhesive agent is applied to the protrusions 15 of the flat plate cores 14 and they are arranged so as to correspond to the pedestal 1 and assembled to the lead frame 2 in the state shown in FIG. Pedestal 1
The portion protruding from the joint surface of the pot-shaped core 9 is the fitting recess 16
, The flat plate core 14 can be easily assembled to the lead frame 2. The pot-shaped core 9 and the flat plate core 14 are fixed to each other by fastening with a clamp or the like. This joining completion state is shown in FIG. Since the pedestal 1 is accommodated in the fitting step portion 13 and the fitting recess 16 with a slight margin in the thickness direction and is not fixed to the pot core 9 and the flat plate core 14, the pot core 9 and the flat core 1
It is possible to join at the joining surface of No. 4.

The boundary between the terminal 3 and the frame portion 4 is cut to disconnect the inductor from the lead frame 2. Figure 5
Shows the finished product of the inductor alone. The terminal 3 has a lead-out groove 10
Since it is led out from the central part, the electric insulation between the pot-shaped core 9 and the flat plate core 14 is good.

[0014]

The method of manufacturing an inductor according to the present invention comprises:
A lead frame-shaped terminal is molded with resin to form a central through hole for inserting a winding shaft that forms a cylindrical winding in the center of a rectangular insulating pedestal, and is molded, and then fitted with a fitting step portion that houses the rectangular insulating pedestal. Since the manufacturing method is formed by assembling the pot-shaped core with the recess and the flat plate core, it is extremely easy to automate the manufacturing process, and the inductor with good insulation between the terminal, the pot-shaped core, and the flat plate core can be obtained. An inexpensive inductor with high reliability can be provided that can be efficiently manufactured with a small amount of adhesive.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a process of an embodiment of a method for manufacturing an inductor of the present invention. FIG. 1 (a) shows an example of a lead frame used in the present invention, in which a rectangular insulating pedestal is partially formed by insert molding. FIG. 3 is an external perspective view showing a formed state. Figure 1
FIG. 3B is an external perspective view showing a state in the middle of the manufacturing process in which the cylindrical winding is provided on the rectangular insulating pedestal of the lead frame. Figure 1
FIG. 6C is an external perspective view showing a state in which the pot-shaped core is mounted on the lead frame from above by covering the tubular winding and the rectangular insulating pedestal. FIG. 1D is an external perspective view showing a state in which a flat plate core is assembled to the lead frame from below and is joined to the pot-shaped core.

FIG. 2 is an enlarged external perspective view of a lead frame showing the rectangular insulating pedestal in FIG. 1A together with a pot core.

FIG. 3 is an external perspective view showing a pot-shaped core used in the present invention.

FIG. 4 is an external perspective view showing a flat plate core used in the present invention.

FIG. 5 is an external perspective view showing a finished product of an inductor alone.

[Explanation of symbols]

 1 Square Insulation Base 2 Lead Frame 3 Strip Terminal 4 Frame Part 5 Circular Hole 6 Central Through Hole 7 Circular Step 8 Cylindrical Winding 9 Vase Core 10 Outlet Groove 11 Center Core 12 Storage Recess 13 Fitting Step 14 14 Plate Core 15 Central protrusion 16 Fitting recess

Claims (1)

[Claims] 1. A method of manufacturing an inductor in which strip-shaped terminals are led outward from mutually opposite side walls of a closed magnetic circuit core composed of a pot-shaped core and a flat plate core, to a lead frame having a plurality of pairs of strip-shaped terminals. , Inserting a rectangular insulating pedestal with an embedded central through hole by projecting the tips of the pair of strip-shaped terminals from the central portion of the opposite side surfaces, and a square fitting step facing the rectangular insulating pedestal. Insert the core of the pot-shaped core, which is concentric with the core and connected to the pair of lead-out grooves, into the cylindrical winding that is concentric with the central through hole on the rectangular insulating pedestal. A step of fitting the insulating pedestal and assembling it to the lead frame, and a flat plate core provided with a central protrusion facing the center of the pot-shaped core on one side and a rectangular fitting recess concentrically corresponding to the rectangular insulating pedestal, Apply adhesive to the central protrusion to cut off the mating recess. A method for manufacturing an inductor, comprising the steps of fitting an edge pedestal and assembling it to a lead frame from below and joining a pot core and a flat plate core.