JPH0266903A - Small-sized coil and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention A6 Objective of the Invention [Field of Industrial Application] The present invention provides a small coil component for preventing unnecessary radiated electromagnetic noise in electronic circuits such as digital equipment, or a primary voltage circuit secondary Small transformer parts used for voltage circuit insulation, etc.
The present invention relates to a method of manufacturing a small coil and a small coil winding frame.

[Conventional technology]

Conventionally, as shown in Figure 4, this type of electronic component is a so-called transformer type that has a winding frame for winding, and its structure is a flat type with an E-type or 1-type shape. Ni-Z
It has a magnetic core 2 made of n-type or Mn-Zn-type ferrite material, has metal terminals on both edges thereof, has a through hole for penetrating the magnetic core 2, and has a drum-shaped outer edge. present,
It is composed of a coil winding frame 3a having a winding trunk portion for winding the winding 5, and a fixing holder 4 for abutting and fixing the magnetic core 2.

First, the tip of the winding 5 is wound several times around the metal lead terminal 6 on one of both edges of the coil winding frame 3a, and the winding is routed through the guide groove 9 to the drum-shaped winding body. After being aligned and wound on the body surface, the terminal ends of the windings 5 are wound around the lead terminals 6 on the other side of both edges of the coil winding frame 3a.

Next, in order to connect the lead terminal of the uncoiled part and the winding, the upper half of the winding sheath is peeled off by soldering heat, and the upper half of the winding is connected.
A coil portion is formed.

Next, the magnetic core 2 is inserted into the coil winding frame, and a fixing holder 4 for fixing the magnetic core 2 is attached to the outer circumference of the magnetic core 2, and then the winding material is protected and the magnetic core 2 and the coil winding frame 3a are fixed. In order to do this, a small coil shell was formed by impregnating it with epoxy or silicone resin and fixing it.

[Problem to be solved by the invention]

Conventionally, with this type of small coil, as electronic devices become smaller and more densely packaged, coil parts also become smaller and more compact.
The coil component shown in FIG. 4 was proposed as a surface-mounted structure on the board surface. However, since the lead terminals are molded integrally with the winding frame in order to achieve miniaturization, the lead terminals are extremely thin and the lead width cannot be made large, and the dimensions of the lead terminals are usually 0.1 to 0.3 m thick.
m, width of 0.6 to 1.5 mm, which tends to be weak in terms of strength.In addition, by winding the winding directly around the lead terminal, the accuracy of the arrangement pitch of the lead terminal is likely to be disrupted, making it difficult for electronic equipment to This has had a significant negative impact on assembly on circuit boards. For this reason, a coil winding frame 3b as shown in FIG. 5 has been proposed in which the winding part and the lead terminals for connection to the circuit board are separated. Although the shape is solved, the winding terminal protrudes further than the board connection lead terminal, and the shape of the lead terminal after connecting the small coil ratio to the circuit board is small and narrow, making it difficult to connect the connection part. Visual confirmation is almost impossible. For this reason, it is difficult to check the solder connections, and as a result, there have been problems with the reliability of conventional small coils when they are mounted on a board.

8. Structure of the invention [Means for solving the problem] The present invention provides a winding frame to which a lead terminal constituting a small coil is attached, a lead terminal for connecting the winding forming the lead terminal and a lead for leading out to the outside. Unlike lead terminals of conventional structure, when the lead terminal for winding and the lead terminal for external lead-out part are viewed from the vertical direction perpendicular to the board surface, the lead terminal for external lead-out and the lead terminal for external lead-out part are By using a winding frame attached with a lead terminal having a structure in which the longitudinal axis of the lead terminal for wire tying is shifted, an inexpensive and highly reliable small coil can be obtained.

That is, the present invention has the following features: 1. In a small coil having an external lead terminal and a winding lead terminal, the winding frame of the external lead terminal and the winding lead terminal extends on the substrate surface. A small coil characterized in that the longitudinal axes extending perpendicularly to the end faces do not overlap with each other with respect to the vertical line of the coil mounting board surface.

2. Form the winding lead terminal and external lead terminal on the lead frame, attach the winding lead terminal in contact with the positioning frame, and connect the winding lead terminal and the winding lead terminal to the position where it touches the positioning frame. 9 at the middle position of the terminal position
Bend it at 0 degrees, insert it into a molding die, mold it with resin into the shape of a coil winding frame, cut off the tip of the lead terminal for winding from the lead frame, and then bend the lead terminal for external extraction again at 90 degrees. This is a method for manufacturing a small-sized coil winding frame, which is characterized by being bent and formed.

[Effect]

The lead terminal shape that forms the winding tangle lead terminal that ties the winding end and the external lead terminal that connects to the board conductor is shaped so that the axes are shifted in advance to form the lead terminal shape. The lead terminal for winding and the lead terminal for external lead-out have a lead frame structure, and when the lead terminal is visually observed vertically on the board surface, the lead terminal for winding and the lead terminal for external lead-out are The lead terminal structure is arranged so that it does not overlap with the vertical line of the surface, making it easy to visually check the soldering finish when the coil or transformer is mounted on the board.

〔Example〕

FIG. 1 shows a small coil according to the present invention, and the magnetic core 2 is made of soft magnetic materials such as Ni-Zn yarn and Mn-Z
These include n-type ferrite materials, pure iron-based powder cores, iron-silicon-aluminum-based powder magnetic cores, or punched silicon steel plate magnetic cores. In the small coil L, a winding 5 is wound around a coil winding frame 3 (hereinafter referred to as winding frame) in which a lead terminal 14 for winding and a lead terminal 13 for external lead-out are implanted. An electrical annealed copper wire with an insulation coating of about 0.05 to 0.2 mm is used. A magnetic core 2 is assembled into a winding frame 3 around which a winding is wound, and the outer periphery of the magnetic core is fixed by a fixing holder 4 to form a small coil.

The winding frame 3 is shown in FIG. 2, and the winding frame 3 has both edges having metal winding lead terminals 14 and external lead terminals 13, and a drum having a through hole 8 in the center. The material is diallylphthalate,
It is made of an engineering plastic material such as phenylene lylphide, and has a guide groove 9 extending vertically from the root of the winding lead terminal 14 to the winding body 7. The winding lead terminal 14 and the external lead terminal 13 are mainly made of copper or a copper alloy, and are made of highly elastic and highly conductive materials such as phosphor bronze, copper-iron alloy, or N52 alloy. It is a metal terminal, and its surface is plated with solderable tin or tin-lead alloy.

FIG. 3(a) shows the winding lead terminal 14 and the lead terminal for external extraction during the manufacturing process of the coil winding frame 3 constituting the small coil 1 of the present invention shown in FIG. 13 shows a lead frame structure.

The lead terminals 13 for leading out to the outside and the lead terminals 14 for connecting the winding wire are manufactured from a band-shaped metal plate by precision punching or photo-etching at regular intervals, thereby forming the band-shaped lead frame 10.

The lead frame 10 includes a narrow positioning frame 11 parallel to both ends, a bridging frame 12 for maintaining this parallel spacing, and lead terminals formed integrally on both edges of the winding frame between the bridging frames 12. Many groups are arranged.

The external lead terminal 13 and the winding lead terminal 14 are vertically disposed facing each other toward the center from the positioning frame 11, and their bases are used as the winding lead terminal 14, In the middle, the part that forms the lead terminal for winding and the part that forms the lead terminal for external lead-out are slightly adjusted, for example, by 0.5 to 1.5
The external lead terminals 13 are formed with a shift of about mm.

Next, a method for manufacturing the small coil winding frame of the present invention will be explained.

FIG. 3(b) shows a plan view of the process of forming the winding frame 3 on the lead frame, and FIG. 3(C) shows a front view of the winding frame in each process.

The lead terminal 13 for leading out to the outside of the coil winding frame 3 and the lead terminal 14 for connecting the winding wire are formed in advance on the lead frame 10 as shown in FIG. 3(b) 3bl.
) A-AM Te 90 degree fold k) Bending, Fig. 3 (
b) (7) 3b2, molded into the shape shown in 3c2 of FIG. 3(C), and immediately inserted into a mold for forming a winding frame.

This bending process is performed just before forming the reel, and the
It also prevents deformation of the bent portion due to winding work, and automates winding frame forming and bending in the same takt time.

Next, we made the engineering plastic material polyphenylene sulfide together with the lead frame.
The lead terminal 13 for leading out to the outside and the lead terminal 14 for connecting the winding wire are integrally molded to form 3b3 in FIG. 3(b) and 3b3 in FIG.
Form into the shape of 3c3 in C).

Next, after cutting and separating the lead terminal portion from the lead frame, the portion of the lead terminal 13 for external extraction protruding from the drum-shaped winding body of the winding frame is folded back in the shape of 3c4 in FIG. 3(C). The winding frame 3 shown in FIG. 2 is completed.

To prepare the small coil, first, the tip of the winding TIA 5 is wound several times around one of the winding winding terminals 14 on both edges of the winding frame 3 shown in FIG. After winding the wire along the winding body 7 to the winding body 7 and winding the winding in an aligned manner, the winding terminals 14 on the other both edges of the winding frame 3 are connected.
Wrap the end and cut it.

Next, the winding terminal 14 is connected by soldering while the coating is thermally peeled off by the heat to form a coil portion.

Next, the magnetic cores 2 are inserted into the through-holes of the winding frame 3, are butt-assembled, and are further fixed with a fixing holder 4.

Then, the magnetic core 2 and the winding frame 3 are fixed together with an epoxy resin adhesive 15 to obtain a small coil.

Incidentally, the standard dimensions of the small coil according to the present invention are 9 mm width on the pin terminal side, 10 mm length of the winding frame, and 5 mm height.

Therefore, according to the present invention, the lead terminal for external lead-out and the terminal for winding are separated, and the position with respect to the circuit wiring of the electronic device and the circuit board due to the disturbance of the terminal arrangement pitch due to the winding of the winding material. Assembling problems such as misalignment can be solved, and since the axes of the external lead terminal and winding terminal are slightly misaligned, the lead terminal and circuit pattern after assembly on the circuit board can be easily adjusted. It is possible to easily check the connection status with the coil, improve visibility, and supply small coils with excellent mass production and stable quality.

C1 Effects of the invention The axes of the lead terminal for winding and the lead terminal for external lead-out of the present invention are shifted from each other with respect to the board surface, and the winding frame to which the lead terminal for winding and the lead terminal for external lead-out is attached is By making the lead terminal into a lead frame structure whose axes are shifted in advance and integrally molding it, it can be easily manufactured with good dimensions, and can be installed inexpensively and with high pitch accuracy on the board.
It is possible to provide a highly reliable small coil whose soldered parts are easily visible.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of a small coil according to the present invention. FIG. 2 is a diagram showing an embodiment of a winding frame for a small coil according to the present invention, in which (a) is a front view and (b) is a side view. FIG. 3 shows a lead frame constituting the lead terminal for a coil winding frame of the present invention, and a process of manufacturing a coil winding frame using the lead frame, and (a) shows the lead frame, the bridging frame, and the lead terminal for external extraction. FIG. 2 is a plan view showing the shape of a winding lead terminal. (b) is a plan view showing the process of manufacturing the coil winding frame. (C) is a front view of (b). 3bl is a diagram in which the external lead terminal side is bent 90 degrees from the lead frame A-A section. 3b2.3c2 is a diagram in which the external lead terminal is bent at 90 degrees. 3b3.3c3 is a diagram showing a coil winding frame. 3
b4.3c4 is a diagram in which the lead frame is cut off and the external lead-out terminal is further bent 90 degrees outward from the coil frame. FIGS. 4 and 5 are perspective views showing examples of conventional small coils. Margin 1 below, ■, River...Small coil. 2...Magnetic core. 3, 3a, 3b...Coil winding frame. 4... Fixed holder 5... Winding wire. 6...Lead terminal. 7... Winding trunk. 8...Through hole. 9...Guide groove. 10...Lead frame. 11...Positioning frame. 12... Bridging frame. 13...Lead terminal for external extraction. 14...Lead terminal for winding. 15...Epoxy resin adhesive.

Claims (2)

[Claims] 1. In a small coil that has an external lead terminal and a winding lead terminal, the external lead terminal and the winding lead terminal that extend on the board surface extend in a direction perpendicular to the end surface of the winding frame. A small coil, characterized in that the longitudinal axes are arranged so that they do not overlap with each other with respect to a vertical line of the surface of the coil mounting board. 2. The winding lead terminal and the external lead terminal are formed on the lead frame, and the winding lead terminal is attached to the position where it contacts the positioning frame, and the position of the winding lead terminal and the winding lead terminal is formed on the lead frame. 9 in the middle position of
Bend it at 0 degrees, insert it into a molding die, mold it with resin into the shape of a coil winding frame, cut off the tip of the lead terminal for winding from the lead frame, and then bend the lead terminal for external extraction again at 90 degrees. A method for manufacturing a small coil winding frame, characterized in that it is formed by bending it several times.