JPH0622970Y2 - Trance - Google Patents

Description

[Detailed Description of the Invention] Industrial Field of Application [0001] The present invention relates to a transformer used in various power supply equipment, video equipment, audio equipment, industrial equipment and the like.

2. Description of the Related Art FIGS. 4 and 5 show a perspective view of a conventionally used transformer and a cross-sectional view of the transformer mounted on a printed circuit board.

As shown in the figure, the iron core 10 is incorporated into the coil bobbin 9 provided with the winding 8, and the rear bottom plate 1 is inserted into the protective case 1.
1 is built in to form a transformer. 12 is bobbin 9
It is an iron core guide brim provided at the upper end of and has a direction determining projection 14.

When the transformer with this configuration is mounted on the printed circuit board 3,
The protective case 1 and the printed circuit board 3 are completely in close contact with each other, and the air 4 trapped between the printed circuit board 3, the protective case 1 and the bottom plate 11 is hermetically sealed.

Problems to be Solved by the Invention When the conventional transformer is mounted on the printed circuit board 3 as described above and soldered by an automatic soldering device or the like,
The sealed air 4 expands rapidly due to the heat of soldering and there is no escape, so the printed circuit board 3 with the pin terminals 5 attached
Inversely ejected from the hole 13 to cause tunnel soldering, immo soldering, no soldering at all, or expanded air 4 causes the transformer to be lifted, resulting in poor floating of the transformer. It had the following drawbacks.

In recent years, the technical development of automatic mounting technology for electronic parts and automatic soldering machines has been remarkable, and even in transformers that had to rely on retrofitting as atypical parts in the past, robots or dedicated atypical parts insert machines The development has reached the level where automatic mounting is possible technically and constructionally, and the advent of a transformer that enables automatic mounting and automatic soldering has been desired.

Therefore, the above problem is a major problem in the trend of automating everything from assembling of electronic parts to soldering, which requires a check after soldering, and also due to visual and manual steps of soldering failure. It is a major obstacle, such as the need for correction.

With the conventional structure, it is difficult to automatically solder the transformer.

Means for Solving the Problems The present invention responds to the demands of such a set maker, and in order to enable automatic soldering of a transformer, an air vent portion formed by notches at one or a plurality of points at the bottom of a protective case. Is provided to form a gap between the substrate and the protective case, and has a structure having a sealed air discharge portion.

Action As described above, the structure that has the air vent part in the protective case and the air exhaust part prevents the air from rapidly expanding due to the heat of soldering in the automatic soldering process after mounting. Since it is not a sealed structure like the one shown in the figure, the expanded air acts so as to be discharged from the air vent part, and it is possible to eliminate defective soldering of the pin terminals due to backflow of the expanded air. .

Embodiment Hereinafter, an embodiment according to the present invention will be described with reference to the drawings.

1 and 2 are cross-sectional views of a transformer incorporating a protective case used in the transformer of the present invention and a transformer mounted on a printed circuit board.

In FIGS. 1 and 2, the coil bobbin 9 having the iron core guide collar 12 is provided with the winding wire 8, and the lead wires 15 at both ends of the winding wire 8 are wound around the pin terminals 5 planted in the coil bobbin 9 and soldered or the like. , And connect the coil bobbin 9 with the iron core 1
0 is incorporated into a transformer body, and the transformer body is housed in a protective case 1 provided with a direction determining protrusion 14 on its upper surface.
A bottom plate 11 is built in the open surface of the bottom surface of the protective case 1 so as to penetrate the pin terminals 5, and air vents 2 formed of rectangular notches are provided on both sides of the lower end surface of the protective case 1. Has been done.

The transformer having such a structure is incorporated in the printed circuit board 3 having the conductive pattern of the copper foil 7 on the lower surface as shown in FIG. That is, the pin terminals 5 are inserted into the holes of the printed circuit board 3, the lower end surface of the protective case 1 is brought into close contact with the printed circuit board 3, and the pin terminals 5 and the copper foil 7 are connected by the solder 6 for use.

As shown in FIG. 1, a rectangular air vent 2 is provided on the lower end surface of the protective case 1 and, as shown in FIG. 2, mounted on the printed circuit board 3 between the printed circuit board 3 and the protective case 1. It is configured to create a void.

That is, as shown in FIG. 2, when soldering is performed in this state, the air 4 between the printed circuit board 3 and the bottom plate 11 is removed.
Is discharged from the air bleeding section 2 and the solder 6 which is automatically soldered is completely attached to the pin terminals 5 and the copper foil 7 of the printed circuit board 3, and defects such as tunnel solder, immo solder and floating of the transformer occur. Things will disappear.

FIG. 3 shows a second embodiment of the present invention. In the first embodiment shown in FIG. 1, the air vent 2 is provided on the side of the protective case 1, but in the second embodiment, it is provided at the corner of the protective case 1.

In addition, although the shape of the air vent 2 is rectangular, a square,
The shape may be a semicircle or the like, or the number of cuts is two in FIG. 1, but it may be a single number or more.

Effects of the Invention As described above, the protective case of the transformer is provided with a notch to serve as an air bleeding part so that the sealed air can be discharged, so that it can be completely soldered when mounted on a printed circuit board. Even in the case of automatic soldering, the reliability can be maintained sufficiently, and the effect of being able to omit processes such as checking and correction can be obtained, which is of great practical value.

[Brief description of drawings]

FIG. 1 is a perspective view of a transformer provided with a notch according to an embodiment of the present invention, FIG. 2 is a sectional view of the transformer mounted on a printed circuit board, and FIG. 3 is a sectional view of the second embodiment. FIG. 4 is a perspective view of a conventional transformer, and FIG. 5 is a sectional view of the transformer mounted on a printed circuit board. 1 ... Protective case, 2 ... Air vent, 3 ... Printed circuit board, 4 ... Air, 5 ... Pin terminals, 6 ... Solder, 7 ...
… Copper foil, 8… Winding, 9… Coil bobbin, 10… Iron core, 11… Bottom plate, 12… Iron core guide collar, 13…
Hole, 15 ... lead wire.

Claims (1)

[Scope of utility model registration request] 1. A coil bobbin is wound with a winding to form a coil portion, and an iron core is incorporated into the coil portion to form a transformer body. A transformer that is housed in a protective case that has an air bleeding part due to a notch.