JPH0690982B2 - Small winding parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial field of application" This invention, an inductance element such as a choke coil,
Regarding a small-sized winding component such as a transformer, it is a winding component in which a terminal portion is joined to a circuit board surface and soldered without inserting terminal pins into the circuit board.

"Prior Art" A so-called chip-type winding component is widely known as a small-sized winding component that can be arranged on a printed wiring board surface and directly soldered.

There are various types of chip type winding parts, for example, an inductor having a structure in which a cap electrode is fitted on both sides of a drum-shaped iron core equipped with a coil and the coil end is soldered to the cap electrode. There is. (Japanese Patent Laid-Open No. 58-70507) Since the chip type inductor as described above can be soldered on the printed wiring board by using the automatic soldering device, electrical contact is made with the mounting, and
This is advantageous in various respects, such as facilitating the design of the printed wiring board.

On the other hand, the small transformer 11 shown in FIGS. 7 and 8 has already been developed.

This transformer 11 consists of a quadrangle with a side of 8 mm when viewed from the top, and the drawing is magnified about 8 times.

In these figures, 12 and 13 are E-shaped cores of the same shape made of ferrite material, 14 is a bobbin, 15 is a coil, 16 is an insulating tape wound around the coil, and 17a to 17f are terminal pins.

The bobbin 14 has a perspective view as shown in FIG.
Collars 14b and 14c are integrally formed on both sides of the rectangular tubular winding portion 14a, and thick portions 14d and 14e for fixing the terminal pins 17a to 17f are further formed below the collars 14b and 14c. It is provided.

The groove between the terminal pins is a guide groove 14f for pulling out the winding end.

The terminal pins 17a to 17f are L-shaped rectangular rod-shaped conductive materials bent substantially at right angles, and are fixed to the lower surfaces of the thick portions 14d and 14e of the bobbin 14 at equal intervals.

The terminal pins 17a to 17f are provided with a predetermined distance X between the upper surface of the bent pin portion (horizontal portion) and the lower surface of the thick portions 14d and 14e, and each of these pin portions is the lower surface of the collar. It is supposed to be parallel.

The coil 15 is mounted on the winding portion 14a of the bobbin 14 by winding a conductive wire with an automatic winding machine.At this winding, a specific terminal pin, for example, an upright portion of the terminal pin 17a ( A step of entwining the winding start end portion at a position corresponding to a predetermined interval X), a step of subsequently winding the winding portion 14a, and then a winding end portion of another terminal pin, for example, an upright state of the terminal pin 17f. The process of pulling up the parts is automatically performed.

A plurality of coils such as a primary coil and a secondary coil are formed on the winding portion 14a, and the winding start end portion and the winding end portion are twisted to each terminal pin in the same manner as above.

In this way, the winding start end and winding end that are automatically entangled in the terminal pins 17a to 17f are soldered by an automatic soldering device or the like and fixed to the upright portions of the terminal pins 17a to 17f.

The cores 12 and 13 described above are mounted after the bobbin 14 is equipped with the coil 15.

That is, the central legs of the cores 12 and 13 are inserted so as to oppose the winding hole inner holes of the bobbin 14, and are fixed by an adhesive in a state where the central leg of each core and the left and right leg end surfaces are aligned. ing.

As shown in FIGS. 7 and 8, the small transformer 11 is mounted on a predetermined portion of the printed wiring board 18 and soldered by an automatic soldering device to be mounted.

The small transformer 11 mounted in this way is
The lower surface of the bent pin portion (horizontal portion) of 17a to 17f is joined and fixed to a predetermined surface of the printed wiring board 18, but in such a small transformer 11, the terminal pin is irradiated with laser light. In many cases, spot solder is applied and fixed.

“Problems to be solved by the invention” While the inductors described above are suitable for miniaturization and are convenient for mounting as described above, the winding parts themselves have a complicated structure, and production is troublesome. Many have drawbacks such as not being suitable for mass production.

For example, in the above-mentioned inductor, since the winding start end and the winding end end of the coil remain pulled out, when winding by an automatic winding machine, there is no fixed position of the winding start end,
Some special means must be provided and fixed to start the winding, and the winding start end and winding end should be pressed against the predetermined places of these cap electrodes and soldered. Therefore, not only is it troublesome to process the coil end portion, but it is difficult to automate the soldering, which tends to be manual work.

In addition, the above-mentioned small transformer 11 does not have such a problem. However, the gap X between the horizontal pin portions of the terminal pins 17a to 17f and the thick portions 14d and 14e of the bobbin collar, and the thickness width of the horizontal pin portion. Since a distance interval due to and occurs between the small wiring transformer 11 and the printed wiring board 18, the small transformer 11 is not stable when soldered to the printed wiring board 18, and the height of the transformer increases by the distance distance. I have a problem to say.

"Means for Solving Problems" The present invention was developed in view of the above problems, in which a terminal pin is planted in a collar of a bobbin equipped with a coil, and a coil end is fixed to the terminal pin. In the winding component, a recess is formed in the lower surface of the collar, and the upright portion of the terminal pin bent in an L shape is planted in the bottom of the recess, and its horizontal portion is located at the same position as the lower surface of the collar. Alternatively, a small winding component is proposed in which the coil end is fixed to the terminal pin portion in the recess by making the coil end parallel to the lower face of the collar at a position slightly protruding from the lower face.

[Examples] Next, examples of the present invention will be described with reference to the drawings.

1 and 2 show a bobbin 19 of the present invention which is provided in a small transformer like the bobbin 14 of the conventional example. The bobbin collar has a plurality of recesses 19g on the lower surface of the thick parts 19d, 19e (19e not shown).
And each terminal pin 17a to 17f on the inner bottom of these recesses 19g.
Has been planted.

The inclined surface communicating with each recess 19g is a guide part for the winding component, and the winding end pulled out from this inclined surface is a recess.
It can be entangled in the upright part of the terminal pin within 19g.

In this embodiment, the lower surfaces of the bent pin portions of the terminal pins 17a to 17f are formed so as to be parallel at the same position as the lower surfaces of the thick portions 19d and 19e of the bobbin collar, or at a slightly protruding position. There is.

3 and 4 show the lower surface of the thickened portions 20d, 20e (20e not shown) of the bobbin collar, leaving both ends 20h, 20i, and the terminal pins 17a-17f are planted on the dug surface 20p. Further, an embodiment regarding the bobbin 20 similar to the above will be shown.

The bottom surface of the bent pin of each terminal pin 17a to 17f is at both ends.
The heights of 20h and 20i are the same, or slightly protruding. 20g is a guide groove at the end of the winding.

By configuring as in the above embodiment, the lower surface of the thick portions 19d, 19e of the bobbin collar comes into contact with the printed wiring board 18, and the approaching state makes the mounting state of the small transformer mechanically and electrically stable. Moreover, since the bottom of the transformer was close to the printed wiring board 18, the small transformer of the conventional example
The height of the transformer can be reduced compared to 11.

As described above, the respective embodiments have been described.
7f may be a square rod having a constant width as shown in the above embodiment, but as shown in FIGS. 5 and 6, if the bending pin portion is formed wide, the winding end of Unravel,
This is advantageous because it can be prevented from coming out.

In FIGS. 5 and 6, the bent portions of the terminal pins 17a to 17f are crushed to be formed wider, but the terminal pins may be formed so that the bent portions are widened in advance.

Further, each of the terminal pins 17a to 17f may be bent in advance into an L-shape, and may be implanted in the thick portion of the bobbin collar, or a straight terminal pin may be formed in advance and the bobbin collar of the bobbin collar may be formed. You may make it bend | fold after implanting in a thick part.

In addition, as explained in the conventional example, the terminal pin is irradiated with laser light or spot solder is applied to the printed wiring board.
Since it is often attached to 18, the tip of the bent pin portion of each terminal pin 17a to 17f is configured to project a little compared to the outer surface of the bobbin collar thick portion 19d, 19e (or 20d, 20e). It is preferable.

In addition, when carrying out the present invention, the present invention is not limited to a small transformer using an E-shaped core, but may be applied to various winding components such as a small transformer using an EI type or a Coco core, or a choke coil other than a transformer. In addition, the terminal pin may have any one of a rectangular bar shape, a round bar shape, and a plate shape.

[Advantages of the Invention] As described above, the present invention is suitable for mass production because the winding ends can be entangled with each terminal pin for automatic winding and the winding ends can be automatically soldered. A chip-type small winding component can be provided.

Further, according to the present invention, since the horizontal portion of the terminal pin is parallel to the lower surface of the collar at the same position as the lower surface of the bobbin collar or at a position slightly protruding from the lower surface of the bobbin collar, when mounting the small winding component on the printed wiring board. In addition, this small winding component is mechanically and electrically stable, and the height of the attached small winding component can be minimized.

[Brief description of drawings]

FIG. 1 is a side view of a bobbin showing an embodiment of the present invention in which each terminal pin is planted in a plurality of recesses formed on the lower surface of the thick portion of the bobbin collar, and FIG. 2 is a part of the bobbin shown in FIG. Enlarged perspective view,
FIG. 3 is a side view of a bobbin showing an embodiment of the present invention in which the lower surface of the thick wall portion of the bobbin is dug down leaving both ends, and each terminal pin is planted on the dug surface, and FIG. 4 is the bobbin shown in FIG. 5 is a partially enlarged perspective view of FIG. 5, FIG. 5 is a simplified view showing a terminal pin having a widened portion, FIG. 7 is a vertical sectional side view of a small transformer shown as a conventional example, and FIG. FIG. 9 is a side view of the transformer, and FIG. 9 is a perspective view of a bobbin provided in the conventional transformer. 11 …… Small transformer 12,13 …… Core 15 …… Coil 17a to 17f …… Terminal pin 19,20 …… Bobbin 19g …… Concave 20p …… Deep face

Claims (1)

[Claims] 1. A winding component in which a terminal pin is implanted in a collar of a bobbin equipped with a coil, and a coil end portion is fixed to the terminal pin, wherein a recess is formed in the lower surface of the collar, and L
The upright part of the terminal pin bent in a letter shape is planted in the bottom of the recess, and its horizontal part is parallel to the lower surface of the flange at the same position as the lower surface of the above flange or a position slightly protruding from the lower surface, and the coil end A small winding component, characterized in that it is fixed to the terminal pin portion in the recess.