JPH10144535A - Coil bobbin device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a so-called whisker of an end of a coil winding winded around a terminal pin and to improve solderability. SOLUTION: A groove 4a is made in a specified area of a terminal pin 4 to be press-fitted to a flange 1a of a coil bobbin. An end 3 of a coil winding is bound on the groove 4a. Since the end 3 can be cut by a corner of the groove 4a, a so-called whisker is not formed and a failure such as short-circuit can be prevented when the coil bobbin is mounted on a board. The area around which the end 3 is found is soldered and the end is connected to an outer circuit. In this case, the soldering is easy because the solderability is promoted by the groove. If the groove 4a is extended from the area around which the end 3 is found to the area to be press-fitted to the coil bobbin, the terminal pin 4 is also prevented from coming off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil bobbin device used for a small transformer or the like.

[0002]

2. Description of the Related Art Generally, a coil winding of a transformer or the like is wound around a body of a coil bobbin, and its end is pulled out to the side of the coil bobbin as a terminal (lead wire), and is erected on the coil bobbin. The terminal pins are soldered to connect to external circuits.

[0003] A conventional coil bobbin apparatus employs a configuration as shown in FIG. The coil winding wound around the coil bobbin is drawn out to the outside as a terminal portion 31 through a through hole 32b provided in a flange portion 32a of the coil bobbin. The terminal 31 is a terminal pin 3 erected on the flange 32a.
3 is wound around a plurality of times and then cut, and the periphery of the tied region is fixed with solder 34 to be connected to the terminal pin 33 so as to be able to conduct with an external circuit.

FIG. 4 is an enlarged view of the standing state of the terminal pins. FIG. 4A shows a state in which a terminal pin 43 composed of a straight round pin is press-fitted. b) is provided with a plurality of retaining grooves 53a on the outer periphery of the press-fit portion of the round pin 53.

[0005]

As described above, when the terminal portion of the coil is wound around the terminal pin formed of a straight round pin and then cut, as shown in FIG. 3, the end of the terminal portion is connected to the terminal pin. , A so-called "whisker residue" occurs to a degree of 0.5 to 3 mm. Such a whisker residue causes a short circuit that comes into contact with the pattern of the circuit board on which the coil bobbin is mounted. In addition, when the terminal section is wound around the terminal pin, the entangled area of the terminal section becomes large, so that when the coil bobbin is mounted on the circuit board, the terminal section may be caught on the circuit board. There is a problem that management of the area is troublesome.

As described above, the configuration in which the terminal portion of the coil winding is wound around the straight terminal pin has several problems. Therefore, the following proposals have been conventionally made as means for solving this problem. I have. In the first method, the binding width of the terminal portion wound around the terminal pin is pushed down by a hollow push-down bar to make the binding width constant (Japanese Utility Model Laid-Open No. 2-73720). No.2: An even number of plate-shaped Z-shaped terminals are provided on the horizontal axis on the coil bobbin, and the terminal is entangled in a slalom shape. Also, the terminal section is prevented from being loosened, loosened, derailed and cut off (Japanese Utility Model Laid-Open No. 5-48314).

[0007] However, the first prior art requires a depressing device, and the second prior art has a problem that the structure is complicated and increases the cost.

[0008]

In order to solve the above-mentioned problems, a coil bobbin device of the present invention can guide a terminal portion of a coil winding and cut the terminal portion into a binding region of a terminal pin. A groove is provided. This groove regulates the width of the binding region and cuts off the terminal at the corner, so that it is possible to prevent the generation of so-called beard residue.

Further, if the groove formed in the terminal pin is expanded from the above-described tied region to a region where the terminal pin is continuously pressed into the coil bobbin, a function of preventing the terminal from coming off can also be provided.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a coil bobbin device according to the present invention, a terminal portion of a coil winding wound around a body portion of a coil bobbin is drawn out of a flange portion of the coil bobbin, and a terminal pin is provided upright on the outside of the flange portion. By soldering the terminal part to the tied area of the terminal pin that tied this terminal part,
In the coil bobbin device in which the terminal portion is connected to the terminal pin, a groove portion for guiding the terminal portion of the coil winding and cutting the terminal portion of the terminal portion is formed in the entangled region of the terminal pin. .

It is desirable that the above-mentioned groove portion of the terminal pin is formed from the entangled region of the terminal portion to the region continuously pressed into the coil bobbin.

[0012]

FIG. 1 shows a main part of a coil bobbin device used in a small transformer. A plurality of coil windings 2 are wound around a body of a coil bobbin 1. FIG. The terminal portion 3 of each coil winding 2 is provided with a flange portion 1a provided on one side of the coil bobbin.
Through the through hole 1b. Outside the flange portion 1a from which the terminal portion 3 is pulled out,
Three terminal pins 4 are provided upright.

Each of the terminal portions 3 drawn from the primary coil and the secondary coil is entangled with a terminal pin 4 and cut off at an end. The region of the terminal pin to which the terminal portion 3 is entangled, ie, the tying region K, is soldered, thereby electrically connecting the terminal portion 3 to the terminal pin 4 to form a coil bobbin device. .

FIG. 2 is an enlarged view of a portion of the flange portion 1a where the terminal pins 4 of FIG. 1 are erected. As shown in the figure, grooves 4a are formed at predetermined intervals in a predetermined range of the terminal pins 4. The groove portion 4a is formed in a tapered shape in which the base portion side is orthogonal to the axial direction and the tip end side is an inclined surface, and prevents the entangled region K from spreading in the axial direction when the terminal portion 3 is wound a plurality of times. When the terminal portion 3 is strongly pulled and the terminal portion 3 is strongly pulled, the terminal portion does not enter the bottom portion so as not to be loosened. When the terminal portion 3 is pulled in the direction of the base portion, the terminal portion 3 can be easily cut by the outer peripheral corner of the groove portion 4a. The groove portion 4a is cut out from the binding region K of the terminal portion 3 to the region where the terminal pin 4 is continuously pressed into the coil bobbin, whereby the terminal pin 4 is pressed into the hole provided in the flange portion 1a of the coil bobbin. It functions as a retaining means when it is done.

In the step of winding the coil bobbin, after winding the wire around the body of the coil bobbin, the terminal 3 is pulled out of the coil winding 2 to the outside of the collar 1a, and the terminal 3 is grooved 4a of the terminal pin 4. After winding several times, the tip is pulled and tightened around the groove 4a. Next, the end portion is cut at the corner by pulling the terminal portion 3 in the base direction. In this manner, since the end can be cut by the corner of the groove, so-called "whisker residue" does not occur.

Next, the terminal portion 3 is soldered to a region where the terminal portion 3 is entangled, and the terminal portion 3 is fixed to the terminal pin 4 by the welded solder 5 to connect the two. This soldering is performed in the same manner as in the prior art. However, since the groove 4a is formed, the soldering area of the terminal pin 4 becomes large due to the groove, so that the soldering area becomes large. The effect is improved, and the effect of facilitating the soldering operation is also added.

Although the present embodiment has been described as a coil bobbin device for a transformer, the present invention is not limited to this. The present invention can be applied to any coil bobbin having terminal pins provided upright.

[0018]

According to the present invention, since the groove is formed in the binding area of the terminal portion of the terminal pin which is press-fitted into the coil bobbin and erected, the terminal portion is guided and the end of the terminal portion is formed in the groove portion. Since the corner can be cut, so-called "whisker residue" does not occur. This can eliminate the cause of a short circuit or the like when the coil bobbin device is mounted on the board. Also, when soldering to the binding area of the terminal,
The formation of the groove in the terminal pin increases the contact area, improves the wettability, and facilitates the soldering operation.

Further, by forming the groove portion from the entangled region of the terminal portion to the region that is continuously press-fitted into the coil bobbin, the groove portion also has a retaining function, and the press-in strength of the terminal pin into the coil bobbin is improved.

[Brief description of the drawings]

FIG. 1A is a front view of an embodiment of the present invention, and FIG. 1B is a partially cutaway side view thereof.

FIG. 2 is an enlarged sectional view of a main part.

FIG. 3 is a partially cutaway sectional view showing a state of a terminal portion and a terminal pin in a conventional technique.

FIG. 4A is a cross-sectional view showing an example in which a straight terminal pin is erected on a coil bobbin according to the related art, and FIG.
FIG. 4 is a cross-sectional view illustrating an example in which a pin having a groove is press-fitted into a press-fit portion.

[Explanation of symbols]

 Reference Signs List 1 coil bobbin 1a collar 2 coil winding 3 terminal 4 terminal pin 4a groove K binding area

Claims (2)

[Claims] 1. A terminal portion of a coil winding wound around a body portion of a coil bobbin is drawn out of a flange portion of the coil bobbin, and the terminal portion is entangled with a terminal pin provided upright outside the collar portion. A coil bobbin device in which the terminal portion is connected to the terminal portion by soldering the terminal portion to the terminal region, and the terminal portion is connected to the terminal portion. A coil bobbin device, characterized in that a groove for guiding the terminal and cutting the terminal of the terminal is formed. 2. The coil bobbin device according to claim 1, wherein the groove is engraved from the entangled region of the terminal portion to a region continuously pressed into the coil bobbin.