JPH0831642A - Surface-mounting air-core coil - Google Patents

Abstract

PURPOSE:To provide a surface-mounting air-core coil which is easily transferred and mounted, stably fitted to a circuit board at a prescribed position, small in size and mounting area, and low in manufacturing cost. CONSTITUTION:A conductor wire 10 is wound on certain times, and input/output terminals are provided onto the conductor wire 10, wherein all the terminals are provided onto flat faces formed on the peripheral side face of a coiled conductor wire 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface-mount air core coil mounted on a circuit board of general electronic equipment or communication equipment.

[0002]

2. Description of the Related Art In recent years, various information communication systems have been remarkably developed, and in keeping with this, there is an increasing need for smaller and lighter information terminals and higher performance. For this reason, mounting of electronic components on a circuit board has become more dense, and there is a strong demand for miniaturization of electronic components. In many cases, miniaturization of electronic components is progressing in the direction of minimizing lead wires as much as possible at the same time as miniaturization of each component (hereinafter referred to as leadless). A coil, which is one of the important components of an electronic circuit, is a coil in which a conductive wire is wound a predetermined number of times, and because of its structure, it is difficult to miniaturize and leadless electronic components.
One. Even if the size is further reduced, it is difficult to stably attach the leadless type coil (hereinafter referred to as the chip type coil) to a predetermined position on the circuit board, and the mounting of the coil component on the circuit board is complicated. I was trying.

Therefore, recently, in order to solve such a problem, the following technique has been proposed (Japanese Utility Model Laid-Open No. 4-52714). Regarding this technique, FIG. 5 (a) and FIG.
This will be described with reference to (b) and FIG. That is, FIG.
FIG. 5A is a side view of a conventional chip-type air-core coil, and FIG.
6B is a front view of a conventional chip-type air-core coil, and FIG. 6 is a mounting view of the conventional chip-type air-core coil on a circuit board. As shown in FIGS. 5 (a) and 5 (b), the conductive wire 1 is wound into a cylindrical shape to form the coil winding portion 2, and a chip-type air-core coil is obtained. At this time, the input / output end 4a of the input terminal 4,
4b is pulled out from the outer peripheral surface of the coil winding portion 2 so as to be included in the surface of the end portion. This chip-type air-core coil is mounted on the wiring circuit 6 formed on the surface of the circuit board 5 as shown in FIG. According to this technology, the conductive wire at the beginning and end of winding of the chip-type air-core coil has a shape in which the legs are widened at both ends of the chip-type air-core coil. It is possible to stably stand on the mounting surface and improve the sitting of the chip-type air-core coil on the circuit board.

[0004]

However, although the conventional chip-type air-core coil disclosed in Japanese Utility Model Laid-Open No. 4-52714 improves the sitting of the coil on the circuit board, conductive wires are provided at both ends of the coil. Since the legs are widened, an extra mounting area for the coils on the circuit board is required, the component mounting density is reduced, and there are problems that the legs are obstructed and hinder the transfer of the coils during the mounting work. Further, since the work of bending the conductive wire is required, the manufacturing cost of the coil is also increased.

Therefore, the present invention solves the above-mentioned problems of the prior art. The coil can be easily transported and mounted, and the coil can be stably mounted at a position on the circuit board, and the size is small, the mounting area is small, and the cost is low. It is an object of the present invention to provide a surface mount type air-core coil.

[0006]

In order to achieve the above object, a surface mount type air-core coil according to the present invention has a plurality of input / output ends provided on a conductive wire by winding a conductive wire a plurality of times. The part is also provided on a plane formed on the outer peripheral side surface of the coil winding part.

Further, it is desirable to form a plurality of planes and to provide a plurality of input / output ends on each plane.

Further, it is preferable that the inductance of the surface-mounted air-core coil can be selected depending on the position where the input / output ends are provided.

[0009]

In the surface-mounting air-core coil of the present invention, a flat surface is formed on the outer peripheral side surface of the coil winding portion, and the input / output end portions are provided in this flat surface. It is easy to perform, and the sitting on the circuit board can be stabilized.

Further, since a plurality of planes having input / output ends are provided on the outer periphery of the surface-mounting air-core coil, any of the planes can be placed on the circuit board without being bothered by the directionality of the planes. Even if it does, it can be implemented stably.

Furthermore, since the inductance can be arbitrarily selected by changing the positions of the input and output ends provided on the plane of the surface-mounting air-core coil, it is possible to obtain various kinds of surface-mounting air-core coils without changing the external dimensions. You can

[0012]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a perspective view of a surface-mounted air-core coil according to an embodiment of the present invention. In FIG. 1, 10 is a conductive wire, 10a is a winding start of the conductive wire 10, 10b is a winding end, 11 is a coil winding portion, and 12a and 12b are first.
Is the input / output end of the. A coil winding portion 11 is formed by densely winding a conductive wire 10 having a wire diameter of 0.3 mm covered with an insulator such as polyurethane as a jig with a winding frame having a flat surface as a jig. There is. Therefore, the coil winding portion 1
1, a flat surface as shown in FIG. 1 is formed on the outer peripheral side. At this time, the winding start 10a of the conductive wire 10 is housed within the surface of the end portion of the surface-mounted air-core coil so as not to protrude outside the surface. Although not shown in FIG. 1, the winding end 10b of the conductive wire 10 is also housed in the end face in the same manner as the winding start 10a, and is configured so as not to project outside from the outer circumference of the coil winding portion 11. Has been done. Here, in order to make a part of the outer circumference of the coil winding portion 11 into a flat surface, there is a method of winding the conductive wire 10 into a cylindrical shape and then forming it, in addition to the method of using the winding frame used in this embodiment. Either method is acceptable. Further, in this embodiment, the coil winding portion 11
Although two planes are formed above and below, it suffices if one plane is formed in order to mount it on the circuit board. Next, a part of the conductive wire 10 included in the flat surface of the coil winding portion 11 to be mounted on the circuit board is irradiated with a laser beam to melt and remove the coated insulating material, and a conductor having a length of 0.5 mm. Part is exposed and is exposed to the first input / output end parts 12a, 12
b. Although the method of irradiating with a laser beam is used here, in addition to this method, the coated insulator is melted and removed by directly contacting it with a heat source such as a soldering iron, or the coated insulator is mechanically removed by a rotating grindstone. There is also a way to do it.
Further, although the first input / output end portions 12a and 12b are provided after forming the coil winding portion 11 here, the conductive wire 10 is previously formed.
There is also a method of forming the coil winding portion 11 by providing the first input / output end portions 12a and 12b and then winding the same. Conductive wire 10
There is no particular limitation as long as an optimum method can be selected in consideration of the wire diameter, the number of turns, the size and shape of the coil winding portion 11, the manufacturing cost, and the like. The surface-mounted air-core coil obtained here is supplied by a parts feeder and placed on a circuit board on which solder paste is printed continuously by a component mounter, and wiring is performed by a continuous movement hot air melting method (reflow). This surface mount air core coil can be continuously mounted by soldering to the circuit. As an example, the inductance is 12n
A 6-turn surface-mount air-core coil for H in the 800 MHz band could be sized 1.5 mm x 1.5 mm x 3 mm. Since the winding start 10a and the winding end 10b of the conductive wire 10 are housed in the end surface and do not project to the outside in the surface mount air core coil according to the present embodiment, there is no clogging due to being caught in the transport path, and the parts feeder can be used. Can be smoothly transported to the component mounter and can be easily mounted. Further, since the flat surface is provided on the outer peripheral side surface of the coil winding portion 11, the coil winding portion 11 can be stably placed on the circuit board, and there is an effect that the sitting is stable and the soldering yield is improved even during the movement in the reflow furnace.

Further, a surface mount type air-core coil according to another embodiment of the present invention will be described. FIG. 2 is a perspective view of a surface mount air core coil according to another embodiment of the present invention. FIG.
FIG. 6 is a mounting view of a surface-mount air-core coil according to another embodiment of the present invention. 2 and 3, 10 is a conductive wire, 10a
Is the start of winding the conductive wire 10 and 10b is the end of winding.
1 is a coil winding part. Reference numerals 12a and 12b are first input / output end portions formed on a flat surface provided on the outer peripheral side portion of the coil winding portion 11, and 12'a and 12'b are first input / output end portions 12 respectively.
The second input / output end portion is formed on a plane opposed to the plane where a and 12b are present. Starting point 10a of winding of conductive wire 10
It is the same as the embodiment of FIG. 1 that the winding end 10b is housed in the end surface and does not project to the outside from the outer peripheral surface of the coil winding portion 11. However, in this embodiment, the coil winding portion is A plurality of planes, here two planes, are provided on the outer peripheral side of 11, and the first input / output end sections 12a, 12b, and the second plane are provided.
I / O end portions 12'a and 12'b are formed by exposing the conductor portion in the vicinity of the winding start 10a and the winding end 10b. Method for forming surface-mounted air-core coil, first input / output end portions 12a, 12b, second input / output end portions 12'a, 1
The method of providing 2'b is the same as that described in the embodiment of FIG. Similar to the embodiment of FIG. 1, the inductance was 12 nH, and the 6-turn surface-mount air-core coil for the 800 MHz band could have a size of 1.5 mm × 1.5 mm × 3 mm. In FIG. 3, reference numeral 13 denotes a wiring circuit provided on the surface of the circuit board 15, and the input / output end portion 12 of the surface-mounted air-core coil is provided by the solder 14.
It is connected to a and 12b. The solder 14 connects the surface-mounted air-core coil to the circuit and mounts it on the circuit board 15. By the way, in order to continuously mount the surface-mounting type air-core coil on the circuit board 15 at high speed, it is appropriate to supply taping by a parts feeder or an embossing method. However, in order to make this possible, in addition to the simple shape of the surface-mounted air-core coil, there is no directivity in the mounting direction, and it is necessary that the circuit board 15 can be mounted as it is, no matter in which direction the circuit board 15 is mounted. Is. In the surface mount air core coil of this embodiment, two opposing flat surfaces are provided,
Since the first input / output end portions 12a and 12b and the second input / output end portions 12'a and 12'b are provided on the respective surfaces, whichever surface is placed on the circuit board 15, it is flat. It is not necessary to pay attention to the directionality of the wiring, and the solder 14 can be conductively connected to the wiring circuit 13.

Next, a surface mount type air-core coil in which the size of the inductance is changed while keeping the same external dimensions and shape will be described with reference to FIG. FIG. 4 is a perspective view of a surface-mounted air-core coil according to still another embodiment of the present invention. The description of the reference numerals common to those in FIG. FIG.
In the above, the winding start 10a and the winding end 10b of the conductive wire 10 are housed in the end surface and have no portion projecting to the outer periphery of the coil winding portion 11, and are mounted on the circuit board on the outer peripheral side of the surface mount air core coil. It is the same as the embodiment of FIGS. 2 and 3 that a flat surface is provided on the side opposite to the mounting side. However, unlike the embodiment shown in FIGS. 2 and 3, the input / output ends are not provided near the winding start 10a and the winding end 10b, but the conductive wire 10 is wound several times and then the conductive wire 10 is wound at that position. The first input / output end portions 12a and 12b and the second portion
I / O end portions 12'a and 12'b are provided. In this embodiment, the input and output ends are provided in the second and fifth windings. Here, the method for forming the coil winding portion 11, the first input / output end portions 12a, 12b, and the second input / output end portions 12'a, 1 '
The method of providing 2'b is as described in the embodiment of FIGS. In the case of this embodiment, the inductance can be changed without changing the size of the surface-mounted air-core coil. For example, as shown in FIG. 4, a surface-mounted air-core coil wound 6 times has an inductance of 7 nH at 800 MHz.
The size was about 1.5 mm x 1.5 mm x 3 mm. As described above, according to this embodiment, the first input / output end portion 12 can be provided without changing the external shape of the surface mount air-core coil.
a, 12b and second input / output end portions 12'a, 12'b
The magnitude of the inductance can be arbitrarily selected only by changing the position of. The fact that this external shape is not changed means that many types of surface-mounted air-core coils can be placed on the circuit board 15 without changing the transportation method, equipment, or jig, which is extremely effective for mounting. Is.

[0015]

As is apparent from the above embodiments, according to the present invention, since a flat surface is formed on the outer peripheral side surface of the coil winding portion and the input / output end portion is provided in this flat surface, the mounting area is reduced. The size can be reduced, the coil can be easily transported and mounted, and the sitting on the circuit board can be stabilized.

Further, since a plurality of planes having input / output ends are provided on the outer periphery of the surface-mounting type air-core coil, it is not necessary to pay attention to the directionality of the planes when mounting.

Further, since the inductance can be arbitrarily selected by changing the position of the input / output end portion provided on the plane of the surface-mounting air-core coil, various types of surface-mounting air-core coils can be transported by using a method, a facility, and a jig. It can be mounted on the circuit board without modification.

[Brief description of drawings]

FIG. 1 is a perspective view of a surface-mounted air-core coil according to an embodiment of the present invention.

FIG. 2 is a perspective view of a surface mount air core coil according to another embodiment of the present invention.

FIG. 3 is a mounting view of a surface-mounted air-core coil according to another embodiment of the present invention.

FIG. 4 is a perspective view of a surface-mounted air-core coil according to still another embodiment of the present invention.

5A is a side view of a conventional chip-type air-core coil, and FIG. 5B is a front view of a conventional chip-type air-core coil.

FIG. 6 is a mounting view of a conventional chip-type air-core coil on a circuit board.

[Explanation of symbols]

 1, 10 Conductive wire 2, 11 Coil winding portion 4 Input / output terminal 4a, 4b Input / output end portion 5, 15 Circuit board 6, 13 Wiring circuit 7, 14 Solder 10a Winding start 10b Winding end 12a, 12b First input Output end 12'a, 12'b Second input / output end

Claims (3)

[Claims] 1. A coil winding portion formed by winding a conductive wire a plurality of times and an input / output end portion provided on the conductive wire, wherein a flat surface is formed on an outer peripheral side surface of the coil winding portion. In addition, the surface mount air-core coil is characterized in that both the input and output ends are provided on the plane. 2. A surface-mount type air-core coil according to claim 1, wherein a plurality of said planes are formed and a plurality of input / output ends are provided on each of them. 3. The surface-mount air-core coil according to claim 1, wherein the inductance of the surface-mount air-core coil is selected depending on the position where the input / output end portion is provided.