JPH10208211A - Coil bobbin and coil provided on the coil bobbin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coil bobbin capable of attaining the miniaturization by reducing the diameter of wires without bringing the defect due to the wire disconnection. SOLUTION: A projected part of a pin 4 is constituted of a wire wound round part 5 wound with a center side part 1b of one end side 1a of the wire 1 and a wire connecting part 6 for connecting a tip part 1c of one end side 1a of the wire 1, then the circumferential surface part of the wire wound round part 5 is formed to the smooth shape, and a corner 6a for cutting off the wire 1 is formed on the wire connecting part 6. Since the wire 1 is wound round the wire wound round part 5, the circumferential surface part of which is formed to the smooth shape, the concentration of large strain is hard to generate on the part abutting on the wire wound round part 5 even though the tension is exerted on the coil 7, and the disconnection of coil 7 does not occur, then the device is miniaturized by reducing the diameter of the wire as much. Since an abutting part D is abutted on the corner 6a to cut off the wire 1 by the concentration of strain, the preparation to arrange a separate cutting means is unrequired, then the constitution is simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil bobbin used for a magnetic head for a floppy disk drive and a coil provided on the coil bobbin.

[0002]

2. Description of the Related Art As an example of a conventional coil bobbin, a terminal pin is fixed to a bobbin body around which a wire is wound, an end of the wire is wound around the terminal pin, and an end (start end and end) of the wire is wound. There is a coil bobbin that is fixed to terminal pins. In this coil bobbin, a wire is cut at a predetermined position (a position close to a terminal pin), and a plurality of coils (and a coil bobbin provided with a coil) can be manufactured by an automatic machine using one wire. ing.

[0003]

By the way, in the above-mentioned coil bobbin or coil, it is necessary to reduce the diameter of the wire as the size becomes smaller. And in this case, although the above-described wire cutting can be easily performed,
As the cutting becomes easier, disconnection failure is more likely to occur. In order to suppress the occurrence of disconnection failure, it is conceivable to increase the diameter of the wire. However, the wire cannot be cut properly, and a part of the wire remains as a whisker. In addition, due to the increase in the diameter of the wire, this measure has not been able to adequately cope with downsizing of the coil bobbin.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coil bobbin that can be reduced in size by reducing the diameter of a wire without causing disconnection failure. Another object of the present invention is to provide a coil that can suppress occurrence of disconnection.

[0005]

According to the first aspect of the present invention,
A coil bobbin provided with a metal pin protruding from a bobbin main body around which a wire is wound and connected to one end of the wire, wherein a protruding portion of the pin is wound around a central portion at one end of the wire. And a wire connecting portion that is provided in connection with the wire winding portion and connects a tip portion on one end side of the wire, and has a smooth peripheral surface portion of the wire winding portion. And an edge portion for cutting the wire is formed at the wire connection portion. According to a second aspect of the present invention, in the configuration of the first aspect, the wire winding portion is covered with a press-deformable soft member.
According to a third aspect of the present invention, in the configuration of the second aspect,
A boss for locking the wire to the flexible member is provided. According to a fourth aspect of the present invention, in the configuration of the second aspect, a cutout portion is formed in the flexible member. According to a fifth aspect of the present invention, there is provided a coil configured by winding a wire around a bobbin body and a pin of the coil bobbin according to any one of the first to fifth aspects.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2, a bobbin main part 2 around which a wire 1 is wound is provided with a terminal block 3 made of a resin which can be pressed and deformed. In the present embodiment, the bobbin main body 2 and the terminal block 3 constitute a bobbin main body. Metal pins 4 are fixed to the terminal block 3 by press fitting or insert molding. The protruding portion of the pin 4 is composed of a square pillar-shaped wire winding portion 5 on the base end side (terminal block 3 side portion) and a square pillar-shaped wire connecting portion 6 connected to the wire winding portion 5. I have. The central portion 1b of the one end 1a of the wire 1 is wound around the wire winding portion 5. The wire winding portion 5 has a corner 5a having a substantially parabolic convex shape (or a substantially circular arc shape), and a peripheral surface portion having a smooth shape. The wire winding portion 5 may be formed in a column shape or a column shape having a substantially elliptical cross section. The distal end portion 1c of the one end side 1a of the wire 1 is wound around the wire connection portion 6. The corner (edge) 6a of the wire connection portion 6 is at 90 °, and the wire 1 can be cut by bringing the wire 1 into contact with the corner 6a and pulling it.

In this coil bobbin, the wire 1 is wound around a wire winding portion 5 and a wire connection portion 6 as shown in FIG. 2, and the wire 1 shown by a dotted line A in FIG.
By pulling in the direction, as shown in FIG. 3, the wire 1 is stress-concentrated at a portion (hereinafter, referred to as a contact portion) D contacting the corner 6a of the wire connection portion 6, and the contact portion D
At one end 1 of the wire 1
The leading end 1c of a is left in a wound state. In this state, the tip 1 of the one end 1a of the wire 1 is soldered.
c is fixed to the wire connection portion 6. The other end 1d of the wire 1 is wound around the bobbin main part 2 and further extends to a pin (not shown). The other end 1 d of the wire 1 and the one end 1 a of the wire 1 constitute a coil 7.

In the coil bobbin configured as described above, the wire 1 is wound around the pin 4, and the end (the portion indicated by the dotted line A in FIG. 2) of the wire 1 is pulled so as to be applied to the corner 6 a of the wire connection portion 6. It is possible to cut the wire 1 at the contact portion D by concentrating the stress on the contact portion D that is in contact with the contact portion D, and it is possible to efficiently manufacture a plurality of coils (and, consequently, a coil bobbin equipped with a coil) with one wire 1 by an automatic machine. Can play well. Further, since the pins 4 are also used for cutting the wire 1, the number of components can be reduced and the configuration can be simplified as compared with a case where a separate wire cutting means is provided. Furthermore, one end 1a of the wire 1
Is wound around the wire winding portion 5 whose peripheral surface has a smooth shape.
As shown in FIG. 4, even when tension is applied to the coil 7 in the direction of the arrow B, a large stress concentration hardly occurs at a portion (hereinafter, referred to as a contact portion) E contacting the corner 5a of the wire winding portion 5. Therefore, the coil 7 is not disconnected. As described above, since a large stress concentration does not occur on the wire 1 and thus no disconnection is caused, the diameter of the wire 1 can be reduced correspondingly and the device can be downsized.

In the coil 7 configured as described above, the central portion 1b at one end 1a of the wire 1 is wound around the wire winding portion 5, and the tip portion 1c is connected to the wire connection portion 6. When a tension acts on the wire 1, the wire winding portion 5 exerts a buffering action to absorb the tension, thereby suppressing disconnection due to the tension. Therefore, it is possible to extend the life of the coil 7 and improve the reliability.

In the first embodiment, the wire winding portion 5 is provided on the base end side (the portion near the terminal block 3) and the wire connection portion 6 is provided so as to be connected to the wire winding portion 5. However, the present invention is not limited to this, and the position of the wire winding portion 5 and the wire connection portion 6 is reversed, and the wire connection portion 6 is positioned on the base end side as shown in FIG. (Terminal block 3 side portion)
(That is, on the tip end side of the pin 4), the wire winding portion 5 may be provided.

In the first embodiment and the coil bobbin shown in FIG. 5, the case where the wire connection portion 6 has a quadrangular prism shape is taken as an example. Instead, the cross section has a substantially star shape as shown in FIG. It may be configured so as to have a triangular prism shape. Further, although the wire connection portion 6 shown in FIG. 6 shows a case where the corner has four star shapes, the wire connection portion 6 may have three star shapes or may have a star shape having five or more corners.

Next, a second embodiment of the present invention will be described with reference to FIGS. Description and illustration of members and portions equivalent to those shown in FIGS. 1 to 6 will be omitted as appropriate. In FIGS. 7 and 8, a rectangular cylindrical portion (a soft member that can be deformed by pressing) 8 that extends outward is formed on the resin deformable terminal block 3. The cylindrical portion 8 covers a part of the wire winding portion 5 and the wire connection portion 6 (the portion near the wire winding portion 5). Then, in the portion of the pin 4 covered by the cylindrical portion 8, the wire 1
Is wound around the cylindrical portion 8 on the pin 4.

In the coil bobbin configured as described above,
Since the wire 1 is wound around the resin-made cylindrical portion 8 that can be pressed and deformed, when tension is applied to the wire 1, the cylindrical portion 8 having a concave surface portion is deformed. For this reason, the tension acting on the wire 1 is absorbed, and accordingly, the force causing the disconnection is reduced and the occurrence of the disconnection is prevented. By preventing the occurrence of disconnection in this way, the diameter of the wire 1 can be reduced by that much, and the device can be downsized.

The cylindrical portion 8 may be formed of a member such as a resin that softens as the heat rises. In this case, the heat of the soldering when the tip 1c of the one end 1a of the wire 1 is fixed to the wire connection portion 6 softens the tube portion 8 and when the wire 1 receives tension, the wire 1 It is possible to further reduce the tension by cutting into the
Consequently, the occurrence of disconnection failure can be suppressed.

In the second embodiment, as shown in FIG. 9, a boss 9 is formed at the end of the cylindrical portion 8, and when the wire 1 is wound around the pin 4, the boss 9 is formed. Wire 1
May be locked. With this configuration, the step 10 formed between the pin 4 and the cylindrical portion 8 is formed.
When the wire 1 is wound around the cylindrical portion 8 beyond the above, the wire 1 can be once locked on the boss portion 9 and the wire 1 can be wound on the cylindrical portion 8 in the locked state. For this reason, when the wire 1 is wound around the cylindrical portion 8, it is prevented that the wire 1 is accidentally dropped to the pin 4 side, so that the wire 1 can be quickly and appropriately wound. That is, when the boss portion 9 as shown in FIG. 9 is not provided (for example, as shown in FIGS. 7 and 8), when the wire 1 is to be wound from the pin 4 side toward the cylindrical portion 8 side, When the wire 1 is wound around the cylindrical portion 8 over the step 10, the wire 1 easily falls off to the pin 4 side, and the winding of the wire 1 cannot be easily performed. In addition, the winding of the wire 1 can be easily performed as described above. The boss 9 is not limited to one, and a plurality of bosses 9 may be provided. By providing a plurality of bosses 9, the wire 1 can be more reliably prevented from falling off, and the wire 1 can be more easily wound.

As a measure for winding the wire 1 around the cylindrical portion 8 over the step 10, for example, one surface portion (an upper surface portion in FIG. 10) 8a of the substantially rectangular cylindrical portion 8 as shown in FIG. A notch 11 is formed on the cut surface 1 of the notch 11.
1a may be configured to be flush with the surface portion 6b of the wire connection portion 6. With this configuration, the wire 1 (coil 7) wound around the wire connection portion 6, the distal end portion of the tubular portion 8 (portion where the notch 11 is formed), and the proximal end portion of the tubular portion 8 are respectively provided. The diameter in the wound state gradually increases. For this reason, when winding the wire 1 around the cylindrical portion 8 beyond the step 10 formed between the pin 4 and the cylindrical portion 8, it is possible to wind the wire 1 stepwise, and The wire 1 can be easily wound and appropriately wound. In the example shown in FIG. 10, the case where the surface portion 8a of the cylindrical portion 8 is notched is shown as an example, but in addition to the upper surface portion, FIG.
A plurality of surface portions such as the left side surface portion 8b or the right side surface portion 8c may be cut out. In each of the above embodiments, the cylindrical portion 8 is formed to protrude from the terminal block 3 and is integrated with the terminal block 3 as an example. However, the present invention is not limited to this, and the cylindrical portion is configured separately from the terminal block 3. May be.

[0017]

According to the first aspect of the present invention, the wire can be cut by the edge of the wire connecting portion, and a plurality of coils (and a coil bobbin provided with the coil) can be manufactured using one wire. By using the pins for cutting the wire, the number of parts can be reduced and the configuration can be simplified as compared with the case where the wire cutting means is separately provided. Furthermore, since the center side portion at one end side of the wire is wound around the wire winding portion having a smooth peripheral surface portion, even when tension is applied to the wire, the portion in contact with the wire winding portion is applied. In this case, a large stress concentration does not occur and the coil is not broken. Further, since the occurrence of disconnection is not caused, the diameter of the wire can be reduced correspondingly, and the device can be downsized.

According to the second aspect of the present invention, since the wire is wound around the flexible member which can be pressed and deformed, when a tension acts on the wire, the flexible member such as a concave surface portion is deformed, and the tension acting on the wire is reduced. Is absorbed, so that the force causing the disconnection is reduced and the occurrence of the disconnection is prevented, so that the diameter of the wire can be reduced by this amount and the device can be downsized.

According to a third aspect of the present invention, when the wire is wound around the cylindrical portion beyond the step formed between the pin and the cylindrical portion, the wire is temporarily locked on the boss portion, and the wire is locked. As it becomes possible to wind the wire around the cylindrical part,
When the wire is wound around the cylindrical portion, the wire is prevented from being accidentally dropped to the pin side, and the wire can be quickly and appropriately wound.

According to a fourth aspect of the present invention, there is provided a wire connecting portion,
Since the diameter of the wire (coil) wound around the portion formed with the notch on the distal end side of the cylindrical portion and the base end portion of the cylindrical portion is sequentially increased, it is formed between the pin and the cylindrical portion. When the wire is wound around the cylindrical portion over a step, the wire can be wound stepwise, so that the wire can be easily wound over the step and appropriately wound.

According to a fifth aspect of the present invention, since the center portion of one end of the wire constituting the coil is wound around the wire winding portion and the tip end is connected to the wire connection portion, the tension on the wire is reduced. When the wire is wound, the wire winding portion exerts a buffering action to absorb the tension, thereby suppressing the occurrence of disconnection due to the tension, and consequently increasing the life of the coil and improving the reliability.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a plan view showing the first embodiment.

FIG. 3 is a front view showing a correspondence relationship between an edge portion of the wire connection portion and the wire according to the first embodiment.

FIG. 4 is a front view showing a correspondence between a wire winding portion and a wire according to the first embodiment.

FIG. 5 is a plan view showing an example in which the positions of a wire connection portion and a wire winding portion are changed as compared with FIGS. 1 and 2;

FIG. 6 is a perspective view showing an example in which the shape of a wire connection portion is changed as compared with FIGS. 1 and 2;

FIG. 7 is a perspective view showing a second embodiment of the present invention.

FIG. 8 is a plan view showing the second embodiment.

FIG. 9 is a perspective view showing an example in which a boss portion is provided on a cylindrical portion.

FIG. 10 is a perspective view showing an example in which a notch is formed in a cylindrical portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wire 2 Bobbin main part (bobbin main body) 3 Terminal block (bobbin main body) 4 Pin 5 Wire winding part 6 Wire connection part 6a Corner (edge part) 7 Coil

Claims (5)

[Claims] 1. A coil bobbin provided with a metal pin protruding from a bobbin main body around which a wire is wound and connected to one end of the wire, wherein the protruding portion of the pin is positioned at a center on one end of the wire. An axis-shaped wire winding portion for winding the side portion, and a wire connection portion provided in connection with the wire winding portion and connecting a tip portion on one end side of the wire, the wire winding portion A coil bobbin, wherein a peripheral portion of the coil bobbin is formed in a smooth shape, and an edge portion for cutting the wire is formed in the wire connection portion. 2. The coil bobbin according to claim 1, wherein the wire winding portion is covered with a soft member capable of being deformed by pressing. 3. The coil bobbin according to claim 2, wherein a boss portion for locking the wire to the flexible member is provided. 4. The coil bobbin according to claim 2, wherein a notch is formed in the flexible member. 5. A coil formed by winding a wire around a bobbin main body and a pin of the coil bobbin according to any one of claims 1 to 4.