JP2599710Y2 - Small transformer - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small transformer used for consumer equipment, and more specifically, a small transformer of a type in which a secondary winding is directly protruded without using a pin terminal on a secondary side and is used as a direct terminal. About.

[0002]

2. Description of the Related Art Conventionally, primary and secondary pin terminals are implanted on respective flanges of a coil bobbin of a transformer, and lead wires at the start and end of winding are defined by predetermined pins. They were entangled with the terminals and then soldered.

[0003]

As described above, in the conventional transformer, the pin terminals for the primary and secondary windings are implanted and the lead terminals are connected to the lead terminals, so that the size of the transformer is reduced. Had limitations.

In order to reduce the size, the pin terminals must be made thin. If the pin terminals are thin, if the lead wires are thick,
When entangled, there is a risk that the pin terminal may be bent and the tensile strength is weak, so that the pin terminal may come off from the coil bobbin, and there is a problem that it cannot be used as a product.

Furthermore, when the lead wire is entangled, the number of entanglements is usually specified, and the entanglement width becomes large with a thin small pin terminal, which may hinder, for example, mounting on a printed circuit board.

[0006] The present invention has been proposed in view of the above, and an object of the present invention is to provide a small transformer suitable for miniaturization and improving the above-mentioned various problems.

[0007]

According to the present invention, a small transformer having a coil bobbin 1 having flanges 3 and 4 formed at both ends of a winding drum 2 is provided. A substantially L-shaped guide groove 6 is formed on the other flange 4 to guide the lead wires 9a and 10a of the secondary winding wound around the winding drum portion 2. 6, the lead wires 9a, 1 drawn through
The above object is achieved by directly drawing Oa to the outside and forming a terminal.

[0008]

In the present invention, the secondary-side pin terminals are omitted, and the lead wires 9a and 10a of the secondary winding are substituted for the pin terminals. For this reason, the size can be reduced by eliminating the need for the secondary-side pin terminals.

Further, since the lead wires 9a and 10a of the secondary winding are drawn out of the flange portion and used as terminals, the step of tying the lead wires to the pin terminals as in the related art can be omitted. The workability is good and the number of parts can be reduced.

[0010] In connection with this, the harmful effect of entanglement with the pin terminal, that is, when entangled with a thin pin terminal, it may bend or pull out. No, on the contrary, 2 wound on a coil bobbin
Since the secondary winding and the lead wire are integrated, there is an advantage that the tensile strength is improved.

Further, the entanglement width does not matter.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of a coil bobbin used in the present invention, FIG. 2 is a front view of the coil bobbin viewed from the direction of arrow A in FIG. 1, and FIG. 3 is a rear view.

In these figures, reference numeral 1 denotes a coil bobbin made of resin. The coil bobbin 1 has a hollow cylindrical winding drum 2 and flanges 3 and 4 formed at both ends thereof. 4 have thick portions 3a and 4a, respectively.

A plurality of pin terminals 5 are implanted in the thick portion 3a of one of the flanges 3, 4 located on the right side in FIG. FIG. 3 shows a pin terminal 5
Shows the state of planting. Note that a lead wire of a primary winding is tied to the pin terminal 5.

The above-mentioned pin terminal 5 is not implanted in the thick portion 4a of the other flange 4 on the opposite side, so that the lead wire of the secondary winding is drawn out and directly led out to the outside. A pair of L-shaped guide grooves 6 for use as pin terminals are formed.

That is, as shown in detail in FIGS. 2 and 4, a substantially U-shaped notch 4 is formed at the center of the thick portion 4a.
The notch 4b is formed with a linear groove 6a extending laterally at the bottom of the notch 4b.
At the end portions, grooves 6b extending perpendicularly and upward are formed, and these grooves 6a, 6b form an L-shaped guide groove 6.

The projections on both sides of the notch 4a defined by the grooves 6a and 6b form hooks 7 for the lead wires.

However, when manufacturing a small transformer,
As shown in FIG. 5, a lower winding 8 as a primary winding is wound on the winding drum 2, and a lead wire at the beginning and end of the winding is tied to the base of the pin terminal 5.

After winding the lower winding 8, the upper winding 9 is wound via an interlayer insulating paper. In detail, as shown in FIG. 6, the lead wire 9 a may be straightly projected upward through the guide groove 6 so as to be hooked on the hook portion 7, and may be cut to have a predetermined length. In addition, the corners on both sides of the lower side of the hooking portion 7 are provided with an R to facilitate guiding the lead wire 9a and not to damage the lead wire 9a.

Thereafter, as shown in FIG. 7, a small transformer can be completed by incorporating the iron core 10 or the like.

[0021]

As described above, according to the present invention, one of the two flanges 3 and 4 has the pin terminal 5 implanted therein, but the other does not have the pin end 5 implanted. Therefore, the size can be reduced.

Further, since the lead wire 9a of the secondary winding that is directly protruded is used as a pin terminal, the step of tying the pin terminal to the pin terminal is reduced, the productivity is improved, and the secondary side pin is used. Terminal components are also unnecessary, and costs can be reduced accordingly.

Further, in the related art, the lead wire 9a of the secondary winding is tied to the pin terminal, and if the pin terminal is thin, there is a possibility that the lead wire may be bent or pulled out. This is not the case. Rather, since the lead wire 9a functioning as a pin terminal is integrated with the secondary winding, there is an advantage that the tensile strength is improved.

Also, since there is no need to entangle, the entanglement width does not matter.

[Brief description of the drawings]

FIG. 1 is a side view of a coil bobbin used in the present invention.

FIG. 2 is a front view of the same.

FIG. 3 is a rear view of the above.

FIG. 4 is a plan view of the same.

FIG. 5 is an explanatory diagram showing a winding state of a winding.

FIG. 6 is an explanatory diagram showing a processing state of a lead wire of a secondary winding.

FIG. 7 is a perspective view showing an assembled state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coil bobbin 2 Winding body part 3, 4 Flange 3a, 4a Thick part 5 Pin terminal 6 Guide groove 6a, 6b groove 7 Hook part 8 Lower winding 9a Leader 9 Upper winding 10a Leader 11 Iron core

Claims (1)

(57) [Scope of request for utility model registration] A flange (3) is provided at both ends of a winding drum (2).
(4) In a small transformer provided with a coil bobbin (1) in which each is formed, a pin terminal (5) is implanted on one of the flanges (3), and the winding is wound on the other flange (4). Lead wire (9a) for the secondary winding wound around the body (2),
A substantially L-shaped guide groove (6) for guiding (10a) is formed, and the lead wires (9a) and (10a) drawn through the guide groove (6) are drawn directly to the outside to form terminals. A small transformer characterized by the following.