JP7637963B2 - Choke coil and manufacturing method thereof - Google Patents

Description

The present invention relates to a choke coil that is installed in rectifier circuits, noise prevention circuits, waveform shaping circuits, resonance circuits, power factor correction circuits, various switching circuits, etc. in AC devices such as power supply circuits and inverters, and a manufacturing method thereof. More specifically, the present invention relates to a choke coil that has a high space factor and is highly efficient to manufacture, and a manufacturing method thereof.

Choke coils installed in the circuits of various AC devices have a winding wound around a circular core covered with an electrically insulating bobbin (for example, Patent Document 1).

JP 2012-59754 A

However, to wind the wire around the core, the winding process must be repeated, with the wire passing through the central window of the annular core and then pulled out. This winding process is not only difficult to mechanize, but also requires several hundred turns when using a thin wire, and while the number of turns is fewer when using a thick wire, the wire is hard, making the process difficult.

The object of the present invention is to provide a choke coil with a high space factor and high manufacturing efficiency, and a method for manufacturing the same.

The method for manufacturing a choke coil according to the present invention includes the steps of:
a core preparation step of preparing a first core and a second core, each of which is insulated by a resin bobbin and has two end edges and is shaped like an arc;
a first core winding step of winding a first winding around the first core to obtain a first core component;
a second core winding step of winding a second winding around the second core to obtain a second core part; and
a butting process for butting edges of the first core part and the second core part on which the winding is provided against each other to form an annular shape;
has.

The bobbin that insulates the first core and the second core can be shaped to have a flange on the outer periphery of the end edge.

The core preparation process can be a process of insulating an annular core with the bobbin and then cutting it to form the first core and the second core.

The second core winding process can be carried out with the outer periphery of one flange of the first core and the outer periphery of one flange of the second core brought into close proximity.

a first A terminal is formed on one end edge of the first core part, and a winding start portion of the first winding in the first core winding process is electrically connected to the first A terminal;
a winding end portion of the first winding is continuous with a winding start portion of the second winding,
A second B terminal is formed on one end edge of the second core part, and the winding end portion of the second winding in the second core winding process can be electrically connected to the second B terminal.

The first A terminal and the start of the first winding in the first core winding process, and the second B terminal and the end of the second winding in the second core winding process can be electrically connected by welding or soldering.

The first core winding process and the second core winding process are forward processes of winding the first winding around the first core and winding the second winding around the second core in a state in which a winding end portion of the first winding is continuous with a winding start portion of the second winding,
After the outward travel step,
a third core winding step of winding a third return winding around the second core; and
a fourth core winding process for winding a fourth return winding around the first core in a state in which the winding end portion of the third winding is continuous with the winding start portion of the fourth winding;
The return process may include

a first A terminal is formed on one end edge of the first core part, and a winding start portion of the first winding in the first core winding process and a winding end portion of the fourth winding in the fourth core winding process are electrically connected to the first A terminal;
A second B terminal is formed on one end edge of the second core part, and the end portion of the second winding in the second core winding process and the beginning portion of the third winding in the third core winding process may be electrically connected to the second B terminal.

The first A terminal and the start of the first winding in the first core winding process and the end of the fourth winding in the fourth core winding process, the second B terminal and the end of the second winding in the second core winding process and the start of the third winding in the third core winding process can be electrically connected by welding or soldering.

a first A terminal is formed on one end edge of the first core part and a first B terminal is formed on the other end edge of the first core part, and a winding start portion of the first winding in the first core winding process is electrically connected to the first A terminal and a winding end portion is electrically connected to the first B terminal;
A second A terminal is formed on one end edge of the second core part, and a second B terminal is formed on the other end edge, and the winding start portion of the second winding in the second core winding process can be electrically connected to the second A terminal, and the winding end portion can be electrically connected to the second B terminal.

The winding direction of the first winding on the first core part and the winding direction of the second winding on the second core part can be the same.

The winding direction of the first winding on the first core part and the winding direction of the second winding on the second core part can be opposite to each other.

The windings can be wire strands.

The butting process can be carried out by inserting an insulating spacer between at least one edge of the first core and the second core.

After the step of manufacturing a choke coil by any one of the above manufacturing methods,
The method may include a step of coating the obtained choke coil with a resin.

The choke coil according to the present invention comprises:
a first core having an arc shape and two end edges, the first core being insulated and covered with a resin bobbin except for at least the end edges, the bobbin having a flange portion on an outer periphery of the end edges;
a second core having an arc shape, the second core having two end edges facing the end edges of the first core, and the second core being insulated and covered with a resin bobbin except for at least the end edges, the second core having a flange portion on an outer periphery of the end edges;
a first A terminal and a second B terminal respectively disposed on the flange portion of one of the opposing end edges of the first core and the second core;
a winding electrically connected to the first A terminal of the first core, wound around the first core, wound around the second core across the other end edge of the first core, and electrically connected to the second B terminal of the second core;
Equipped with.

The choke coil according to the present invention is
a first core part including: a first core having two end edges, the first core being arc-shaped with at least the ends thereof insulated by a resin bobbin, the bobbin having a flange on the outer periphery of the end edges; a first winding wound around the first core; a first A terminal electrically connected to a winding start portion of the first winding; and a first B terminal electrically connected to a winding end portion of the first winding;
a second core part including a second core having two end edges, the second core being arc-shaped with at least the end edges being insulated and covered with a resin bobbin, the bobbin having a flange on the outer periphery of the end edges, a second winding wound around the second core, a second A terminal electrically connected to a winding start portion of the second winding, and a second B terminal electrically connected to a winding end portion of the second winding;
Equipped with
The end edges of the first core part and the end edges of the second core part are disposed opposite to each other.

In addition, the choke coil product of the present invention is
The periphery of the above-described choke coil is coated with resin.

According to the manufacturing method of the choke coil of the present invention, the first and second windings are first wound across the insulating, arc-shaped first and second cores, and then the edges of the first and second cores are butted together to obtain a choke coil. Because the first and second cores are arc-shaped, winding the windings is much easier than with an annular core, and the manufacturing of the windings and choke coils can be automated, making it possible to maximize the manufacturing efficiency of the choke coil. In addition, because the space factor of the windings can be increased compared to when the windings are wound around an annular core, it is possible to achieve a choke coil that is smaller, lighter, more efficient, and has a lower DC resistance.

In addition, according to the manufacturing method of the choke coil of the present invention, a first core part having a first winding wound around a first core and a second core part having a second winding wound around a second core are produced, and a choke coil can be obtained by butting the edges of the first core part and the second core part together. Then, by electrically connecting the terminals of the first core and the second core, a one-phase choke coil for use in a PFC circuit or the like can be obtained when the first winding and the second winding are wound in the same direction, and a common mode choke coil can be obtained when the first winding and the second winding are wound in opposite directions.

In particular, for choke coils used in high-frequency applications that handle frequencies of 10 kHz or more, it is common to use Litz wire to suppress the skin effect, but since Litz wire is twisted, it has a poor winding space factor and is prone to unwinding, making winding difficult. Furthermore, the wire diameter and number of twists must be specially designed and prepared according to the frequency, which makes it unavoidable to both work and increase the cost. However, if the manufacturing method for choke coils of the present invention is used, Litz wire is not required due to the use of stranded wires, and since it is not twisted, the winding space factor is high and the number of wires can be set as desired. In addition, by winding the wire in one direction from the beginning to the end, stray capacitance can be reduced, and high efficiency can be achieved, especially in high-frequency choke coils, by reducing the size, weight, and DC resistance. These factors allow for price reduction and even greater benefits.

FIG. 1 is a perspective view of a choke coil according to a first embodiment of the present invention. FIG. 2 is a perspective view of the annular core before being coated with resin. FIG. 3 is a perspective view of the annular core coated with resin, as viewed from the bottom side. FIG. 4 is a perspective view of a resin-coated annular core cut into a first core and a second core. FIG. 5 is a perspective view of the cut first and second cores, which are opened and arranged side by side and have terminals attached thereto. FIG. 6 is a perspective view showing a state in which windings are wound around the first core and the second core. 7 is a rear view of FIG. 6 as seen from the flange side, which is the side opposite to the terminals. FIG. 8 is an explanatory diagram showing the winding direction, winding direction, and magnetic flux direction of windings in only one direction (only the forward path) provided on the first core and the second core. 9A and 9B are explanatory diagrams showing the winding direction, winding direction, and magnetic flux direction of the return windings applied to the first core and the second core, with FIG. 9A showing the outward path and FIG. 9B showing the return path. FIG. 10 is a perspective view showing a process of bringing the end edges of the first core part and the second core part into opposition to each other. FIG. 11 is a perspective view showing a state in which the end edges of the first core part and the second core part face each other. FIG. 12 is a plan view of the choke coil of the first embodiment. FIG. 13 is a front view of the choke coil of the first embodiment. FIG. 14 is a rear view of the choke coil of the first embodiment. FIG. 15 is a bottom view of the choke coil of the first embodiment. FIG. 16 is a left side view of the choke coil of the first embodiment. FIG. 17 is a right side view of the choke coil of the first embodiment. FIG. 18 is a perspective view of a choke coil product of the first embodiment in which the obtained choke coil is housed in a casing by being covered with a resin. FIG. 19 is a perspective view of FIG. 18 as seen from the bottom side. FIG. 20 is a perspective view of the resin-coated annular core of the second embodiment cut into a first core and a second core. FIG. 21 is a perspective view showing a state in which the first winding and the second winding are wound around the first core and the second core, respectively. FIG. 22 is a perspective view of a first core part having a first A terminal and a first B terminal attached to a first winding, and a second core part having a second A terminal and a second B terminal attached to a second winding. FIG. 23 is a perspective view showing an assembly process of the choke coil in which the first core part and the second core part are placed on the base. FIG. 24 is a perspective view of the choke coil of the second embodiment. FIG. 25 is a perspective view of a choke coil product in which the choke coil of the second embodiment is housed in a casing by being covered with resin, as viewed obliquely from below.

The following describes a choke coil 10 according to one embodiment of the present invention with reference to the drawings.

First Embodiment
1 is an external perspective view of a choke coil 10 according to an embodiment of the present invention. As shown in the figure, the choke coil 10 comprises a first core 30 and a second core 40, each of which is covered with an electrically insulating bobbin 31, 41, and is configured by winding a winding 50 (50a, 50b) around the cores 30, 40. The bobbins 31, 41 are formed with flanges 32, 33, 42, 43, and the winding 50 is electrically connected to terminals 37a, 47b formed on the flanges 32, 42.

The choke coil 10 of the first embodiment can be fabricated as follows.

<Annular core 20>
As described below, the choke coil 10 of the present invention has an annular core 20 cut and installed inside. As shown in Fig. 2, the annular core 20 is an annular body formed from a magnetic material, and although it is illustrated as having a circular shape in a plan view, it may be an elliptical shape, a track shape, a rectangular shape, or the like. The cross-sectional shape of the annular core 20 is not limited, but is illustrated as being substantially rectangular. Examples of the annular core 20 include a dust core or a ferrite core formed by compacting and sintering magnetic powder.

<Coated annular core 22>
As shown in FIG. 3, the annular core 20 is covered with a bobbin 21 made of an electrically insulating resin to produce a covered annular core 22. The resin covering can be performed by insert molding or the like. The bobbin 21 has protrusions 24, 25 formed at positions facing each other in the radial direction. The protrusions 24, 25 are divided into two in the subsequent cutting process to form the flanges 32, 33, 42, 43 of the first core 30 and the second core 40. In addition, terminal mounting portions 34, 44 (see also FIG. 4) that serve as installation positions for terminals 37a, 47b are formed on both sides of the outer periphery of one of the protrusions 24. Furthermore, positioning pieces 35, 45 can be protruded on the outer periphery between the protrusions 24, 25 as necessary for fixing and positioning the covered annular core 22 in the cutting process, and for positioning during insert molding of the casing 60 described later (FIGS. 11 and 12).

<Cutting process>
The coated annular core 22 shown in Fig. 3 is cut so as to bisect the protrusions 24, 25 as shown in Fig. 4. The cutting can be performed, for example, by using a cutting wheel. Laser cutting, water jet cutting, or the like may also be used. By the cutting process, the coated annular core 22 is cut into an arc-shaped first core 30 and a second core 40 as shown in Fig. 4. The first core 30 has flanges 32, 33 formed by cutting the protrusions 24, 25 on the peripheral surfaces of the edges 30a, 30b of the core material, and the second core 40 has flanges 42, 43 formed by cutting the protrusions 24, 25 on the peripheral surfaces of the edges 40a, 40b of the core material. The first core 30 and the second core 40 each have a terminal attachment portion 34, 44 continuous with one of the flange portions 32, 42, and also have positioning pieces 35, 45 protruding from the outer periphery between the flange portions 32, 33 and the flange portions 42, 43, respectively.

<Terminal attachment process>
5, a first A terminal 37a and a second B terminal 47b are attached to terminal attachment portions 34, 44 of the cut first core 30 and second core 40, respectively. The terminals 37a, 47b can be composed of winding holding portions 38, 48 that sandwich the winding 50 (50a, 50b) and are electrically connected to the winding 50 (50a, 50b), and electrical contact portions 39, 49 for electrically connecting the choke coil 10 to other electrical circuits, such as a substrate, and electronic components.

<Winding process>
6 and 7, a winding 50 (50a, 50b) is wound around the first core 30 and the second core 40 to form the first core part 3 and the second core part 4. The winding 50 may be an insulating-coated conductive wire such as an enamel wire or a fusion wire. The winding 50 may be a solid wire or an assembled wire (so-called parallel wire) in which a plurality of solid wires are arranged in parallel.

In this embodiment, the winding 50 is a continuous first winding 50a and second winding 50b. The winding 50 includes a first winding process in which the first winding 50a is wound around the first core 30, and a second winding process in which the second winding 50b is wound around the second core 40. More specifically, in the first winding process, the first winding 50a is wound around the first core 30 from the first A terminal 37a arranged at one end of the first core 30 as the winding start portion 52 to the winding end portion 53 at the other end of the first core 30 to produce the first core part 3. Following the first core winding process, in the second winding process, the second winding 50b extends to the second core 40 so as to straddle the flanges 33 and 43, and is wound around the second core 40 in the same direction as the first core 30 from the winding start 54 of the second core 40 close to the winding end 53 of the first core 30 so that the second B terminal 47b becomes the winding end 55, thereby producing the second core part 4. The winding pattern of the forward process consisting of the first core winding process and the second core winding process is shown in FIG. 8. In FIG. 8 and FIG. 9, which will be described next, the arrow indicating the winding direction represents the winding direction as seen from the edge 30a side of the first core 30. When the winding 50 (50a, 50b) is wound as shown in FIG. 8, when a current flows from the first A terminal 37a side, magnetic flux in the same direction is generated in the first core part 3 and the second core part 4 as shown by the arrow direction.

As shown in FIG. 9(a), the return winding pattern may include a third core winding process in which, after winding the winding 50 (50a, 50b) in the same forward process as in FIG. 8, the second B terminal 47b is used as the winding start portion 55 (winding end portion of the forward process), and the third winding 50c is wound around the second core 40 in the opposite winding direction to the forward winding, and a fourth core winding process in which the winding 50 reaches the first core 30 so as to straddle the flange portions 33, 43, and the fourth winding 50d is wound around the first core 30 in the opposite winding direction to the forward winding, and the first A terminal 37a is used as the winding end portion 52 (winding start portion of the forward process). When the winding 50 is wound as shown in FIG. 9, when a current flows from the 1A terminal 37a side, magnetic flux is generated in the first core part 3 and the second core part 4 in the same direction in the forward and return paths, as shown by the arrows in the figure. Note that it is desirable to extend the winding 50 to the terminals 37a and 47b and wind it at both the winding start part (winding end part) 52, 55.

When winding the winding 50, it is desirable to arrange the flanges 33, 43 without terminals 37a, 47b close to each other so that the terminals 37a, 47b are located on both sides of the first core 30 and the second core 40, as shown in FIG. 5. Then, in the forward process, the winding 50a is wound from the first A terminal 37a through the first core winding process, straddling the flanges 33, 43, through the second core winding process, and up to the second B terminal 47b. The return process can be selectively performed, and the winding is wound from the second B terminal 47b as the winding start 54 through the third core winding process by the third winding 50c, straddling the flanges 33, 43, and up to the first A terminal 37a through the fourth winding process by the fourth winding 50d.

As shown in FIG. 7, the winding 50 straddles the flanges 33, 43 when moving from the first core part 3 to the second core part 4, or from the second core part 4 to the first core part 3. Since the winding 50 has the same winding direction in the first core part 3 and the second core part 4 as shown in FIG. 8 and FIG. 9, the straddling part 51 of the winding 50 straddles the flanges 33, 43 diagonally as shown in FIG. 7. At this time, it is preferable to straddle the flanges 33, 43 with some slack so that the straddling part 51 is not pulled and cut when the edges 30a, 40a and edges 30b, 40b of the first core part 3 and the second core part 4 are butted against each other in the subsequent butting process.

In the winding process, since the first core part 3 and the second core part 4 are in an arc shape, not an annular shape as in the prior art, the winding 50 (50a, 50b) can be wound around the cores 30, 40, and does not need to be passed through the central window of the annular core as in the prior art. This has the advantage that the winding 50 can be wound very easily. In addition, since the winding 50 can be wound tightly, the proportion (space factor) of the central window formed when the first core part 3 and the second core part 4 are connected in an annular shape can be increased as much as possible.

<Butting process>
By winding the winding 50 in the winding process, the first core part 3 and the second core part 4 are connected by the winding 50 that straddles the flange parts 33, 43 via the straddling part 51, as shown in Fig. 6 and Fig. 7. From this state, as shown by the arrows in Fig. 10, the flange parts 32, 42 of the first core part 3 and the second core part 4 are brought close to each other so that the edges 30a, 40a on which the terminals 37a, 47b are formed face each other. Then, as shown in Fig. 11, the edges 30a, 40a and edges 30b, 40b of the first core part 3 and the second core part 4 are butted against each other, so that the first core part 3 and the second core part 4 have an annular shape. In addition, the core materials of the first core part 3 and the second core part 4 may be butted together so as to be in close contact with each other, or an insulating spacer may be inserted between the edges 30a, 40a and/or the edges 30b, 40b to form a gap.

<Winding-Terminal Connection Process>
After the first core part 3 and the second core part 4 are butted together in an annular shape, the insulating coating of the winding 50 is removed from the winding start parts 52, 54 and winding end parts 53, 55 which are to be connected to the terminals 37a, 47b, and the winding holding parts 38, 48 of the terminals 37a, 47b are bent as shown in Fig. 1 to be electrically connected to the terminals 37a, 47b. The removal of the insulating coating of the winding 50 and the electrical connection can be performed by various welding techniques such as resistance welding such as heat crimping or fusing, TIG welding and plasma welding, or by soldering.

As a result of the above, a choke coil 10 can be obtained in which a winding 50 is wound on the first core part 3 and the second core part 4, which are formed in an annular shape, with the winding 50 running from the first A terminal 37a to the second B terminal 47b as a forward path, or a one-phase choke coil 10 for use in normal mode can be obtained in which a winding 50 is further wound on the second B terminal 47b to the first A terminal 37a as a return path.

The obtained choke coil 10 comprises a first core part 3 and a second core part 4 in which the winding 50 is tightly wound around the first core 30 and the second core 40, and the space factor of the winding 50 can be increased to 65% to 70% or more. By improving the space factor of the choke coil 10, the inductance can be increased, and the choke coil 10 itself can be made smaller, lighter, more efficient, and have a smaller DC resistance. In particular, the space factor of the winding 50 can be increased by using stranded wire instead of Litz wire in addition to a single wire.

In addition, if the winding 50 is wound in one direction from the beginning to the end, it becomes possible to wind without turning back, which makes it possible to suppress unnecessary stray capacitance during high frequency operation. Furthermore, it can fully withstand a high voltage of over 400V applied between the beginning and end of the winding, as in a choke coil used in a PFC circuit, which will be described later.

In addition, the windings 50a, 50b wound around the first core 30 and the second core 40 are electrically insulated by the flanges 32, 33, 42, 43, preventing electrical contact or short circuits between them.

<Resin coating process>
In the above-mentioned choke coil 10, because the first core part 3 and the second core part 4 are not fixed relative to each other, a gap occurs at the butt joint of the cores 30, 40, causing the gap to open up. Therefore, as shown in Figures 18 and 19, the choke coil 10 can be resin-coated by insert molding, resin casting (potting), or the like, and placed inside a casing 60 to produce a choke coil product 12. By housing the choke coil 10 inside the casing 60, it is possible to improve the heat dissipation characteristics and achieve uniform heat distribution. Furthermore, by flattening the top surface of the casing 60 as shown in Figure 18 and increasing the area that comes into contact with a heat sink, etc., it is possible to further improve the heat dissipation characteristics.

Since the choke coil 10 has positioning pieces 35, 45 protruding from the circumferential surface as shown in FIG. 1, for example, when the coil is placed in a mold, the positioning pieces 35, 45 can be placed against the inner surface of the mold to perform positioning and fixing. Then, insert molding can be performed so that the electrical contacts 39, 49 of the terminals 37a, 47b protrude from the bottom surface of the casing 60. By providing a space between the first core part 3 and the second core part 4, the edges 30a, 40a and/or the edges 30b, 40b when the choke coil 10 is placed in the mold, a gap can be formed between the edges when the resin coating is performed.

The illustrated choke coil product 12 has a QR code (registered trademark) or a data matrix 61 printed on the casing 60, which describes the product characteristics of the choke coil 10. In addition, reinforcing dummy pins 62, 62 are integrally molded on the underside of the casing 60, separate from the electrical contacts 39, 49.

The choke coil product 12 having the above configuration can be installed on a substrate or the like and used as a choke coil for noise prevention circuits, waveform shaping circuits, resonant circuits, various switching circuits, and the like in AC devices such as power supply circuits and inverters. The choke coil product 12 of the present invention can be suitably used as a choke coil used to counter high-frequency distortion currents in circuits equipped with a power factor correction circuit in switching power supplies and the like used as choke coil products for high frequencies exceeding 10 kHz, and can also be used as an impedance matching, high-frequency smoothing choke coil.

The choke coil 10 and choke coil product 12 of the present invention can extremely easily wind the windings 50 by cutting the coated annular core 22 into the arc-shaped first core 30 and second core 40. The windings 50 can be automated using a flyer-type winding machine or the like. Therefore, the windings 50 can be precisely wound, and mechanical winding has the advantage of allowing the number of turns (turns) to be accurately controlled. Furthermore, when winding the windings 50 using a flyer-type winding machine, if multiple windings 50 are set on the nozzle of the winding machine and wound, the windings 50 can be twisted into Litz wire while being wound.

In the above embodiment, the coated annular core 22 is completely cut into two pieces in the cutting process to obtain the first core 30 and the second core 40. However, as a modified example, the tip of the projection 25 may be left uncut, and the first core 30 and the second core 40 may be opened with the flanges 33, 43 connected in a hinged manner, the windings 50 may be wound around them, and the hinge portion may be folded to butt the first core 30 and the second core 40 together.

The number of windings 50 (number of cores) wound around the first core 30 and the second core 40 can be set appropriately according to the frequency. For example, when winding multiple windings 50, the multiple windings 50 can be wound in parallel by repeating the forward process, or the forward process and the return process, multiple times.

Second Embodiment
In the first embodiment, the winding 50 (50a, 50b) that spans from the first core component 3 to the second core component 4 is wound around the first core 30 and the second core 40. In contrast, in the second embodiment, the first core component 3 having the winding 50a wound around the first core 30 and the second core component 4 having the winding 50b wound around the second core 40 are separately manufactured, and these are placed on a base 63 to obtain a choke coil product 12. Note that the same or similar members as those in the first embodiment are denoted by the same reference numerals, and descriptions thereof will be omitted as appropriate.

The first core 30 and the second core 40 of the second embodiment can be obtained by resin-coating the annular core 20 (see FIG. 2) as in the first embodiment and cutting it to form the flanges 32, 33, 42, and 43 as shown in FIG. 20 (cutting process). The flanges 32, 33, 42, and 43 are provided with locking receiving portions 32a, 42a, etc. for mounting the first core part 3 and the second core part 4 to the flange locking portion 64 of the base 63, which will be described later. In the illustrated embodiment, the locking receiving portions 32a, 42a are vertical cuts.

As shown in FIG. 21, the first winding 50a is wound around the first core 30 to obtain the first core component 3, and similarly the second winding 50b is wound around the second core 40 to obtain the second core component 4 (winding process). The first winding 50a and the second winding 50b are not continuous windings, but are each composed of separate windings or winding groups.

Specifically, the first winding 50a is wound around the first core part 3 so that the flange 32 of the first core 30 is the winding start part 52 and the flange 33 is the winding end part 53. The second core part 4 is wound with the second winding 50b so that the flange 43 of the second core 40 is the winding start part 54 and the flange 42 is the winding end part 53. The winding directions of the windings of the first core part 3 and the second core part 4 will be described later.

In the first embodiment, the winding 50 needs to be wound so as to straddle the first core 30 and the second core 40, but in this embodiment, the windings 50a and 50b can be wound around the arc-shaped first core 30 and the second core 40, respectively, making the winding process extremely easy and automating the winding process extremely easy.

22, the first A terminal 37a and the first B terminal 37b are connected to the winding start portion 52 and the winding end portion 53 of the first winding 50a of the first core part 3, and the second A terminal 47a and the second B terminal 47b are connected to the winding start portion 54 and the winding end portion 55 of the second winding 50b of the second core part 4 (terminal attachment process, winding-terminal connection process). The connections between the terminals 37a, 37b and the first winding 50a, and between the terminals 47a, 47b and the second winding 50b can be made by various welding methods such as resistance welding such as heat crimping and fusing, TIG welding, and plasma welding, or by soldering.

As shown in FIG. 22, the terminals can be configured such that the first A terminal 37a and the first B terminal 37b protrude downward from the first core component 3, and the second A terminal 47a and the second B terminal 47b protrude downward from the second core component 4.

As described above, the first core part 3 and the second core part 4 are independent parts, not connected by a winding, and are therefore very easy to handle. Note that, when the windings 50a, 50b of the first core part 3 and the second core part 4 are wound in the same direction, the first core part 3 and the second core part 4 can have the same configuration.

23, the first core part 3 and the second core part 4 are placed on the base 63 by bringing the flanges 32, 42 and 33, 43 close to each other so that they face each other (butting process). The base 63 is formed with flange locking parts 64 into which the locking receiving parts 32a, 42a of the flanges 32, 33, 42, 43 fit. In the illustrated embodiment, the flange locking parts 64 are protrusions into which the locking receiving parts 32a, 42a fit. The first core part 3 and the second core part 4 can be attached to the base 63 by engaging the flanges 32, 42 and the flanges 33, 43 with the flange locking parts 64, respectively. In addition, it is desirable to form a claw piece 65 on the base 63 that hooks onto the flange parts 32, 33, 42, and 43, and to lock the flange parts onto the claw piece 65 so that the first core part 3 and the second core part 4 do not fall off the base 63.

As shown in FIG. 23, the base 63 has notches formed to avoid the terminals 37a, 37b, 47a, and 47b, and terminal engagement pieces 66 that engage with the terminals 37a, 37b, 47a, and 47b protrude from the notches. Then, as shown in FIG. 24, the first core part 3 and the second core part 4 are attached to the base 63, and the terminals 37a, 37b, 47a, and 47b are engaged with the terminal engagement pieces 66, so that these terminals protrude below the base 63 and are fixed in place.

In this state, as shown in FIG. 25, the choke coil 10 is resin-coated by insert molding, resin casting (potting), or the like, and then housed inside the casing 60 (resin coating process), to obtain the choke coil product 12 with terminals 37a, 37b, 47a, and 47b protruding downward. In the case of this embodiment, dummy pins as in the first embodiment are not necessary.

The obtained choke coil product 12 can be mounted on a substrate or the like and used as a choke coil for noise prevention circuits, waveform shaping circuits, resonant circuits, various switching circuits, and the like in AC devices such as power supply circuits and inverters. For example, by connecting terminal 37b and terminal 47b in series, choke coil product 12 can be used as a one-phase choke coil. Also, by connecting terminal 37a and terminal 47a, and terminal 37b and terminal 47b in parallel, it can be used as a two-phase choke coil.

The choke coil product 12 can be used as a common mode choke coil by reversing the winding directions of the first winding 50a and the second winding 50b of the first core component 3 and the second core component 4 and connecting terminals 37a and 47b in parallel, and terminals 37b and 47a in parallel.

According to the second embodiment, the first core part 3 and the second core part 4 are arc-shaped, making it easy to wind the windings 50a, 50b, and the manufacturing of the windings and the choke coil product 12 can be automated, thereby increasing the manufacturing efficiency of the choke coil product 12 as much as possible. In addition, the space factor of the windings can be increased compared to when the windings are wound around an annular core, making it possible to reduce the size, weight, and efficiency of the choke coil product 12, as well as to reduce the DC resistance.

The above explanation is for the purpose of explaining the present invention, and should not be interpreted as limiting the invention described in the claims or narrowing its scope. Furthermore, the configuration of each part of the present invention is not limited to the above embodiment, and various modifications are possible within the technical scope described in the claims.

10 Choke coil 12 Choke coil product 3 First core part 30 First core 32, 33 Flange part 37a First A terminal 37b First B terminal 4 Second core part 40 Second core 42, 43 Flange part 47a Second A terminal 47b Second B terminal 50 Winding 51 Spanning part

Claims (12)

a core preparation step of preparing a first core and a second core, each of which is insulated by a resin bobbin and has two end edges and is shaped like an arc;
a winding process for winding the first core and the second core;
a butting process for butting edges of the first core part and the second core part on which the winding is provided against each other to form an annular shape;
A method for manufacturing a choke coil, comprising:
The winding process includes:
a first core winding step for winding a first winding of an outward path so that one end edge side of the first core is a first winding start portion and the other end edge side is a first winding end portion to obtain a first core component, and a second core winding step for winding a second winding of an outward path so that one end edge side of the second core is a second winding start portion and the other end edge side is a second winding end portion to obtain a second core component;
a third core winding step of winding a third return winding from the third winding start part to the third winding end part, with the second winding end part of the second core as a third winding start part and the second winding start part as a third winding end part, and a fourth core winding step of winding a fourth return winding from the fourth winding start part to the fourth winding end part, with the first winding end part of the first core as a fourth winding start part and the first winding start part as a fourth winding end part,
In the forward process, the first winding and the second winding are wound in a state in which the first winding end portion is continuous with the second winding start portion,
In the return process, the third winding and the fourth winding are wound in a state in which the third winding end portion is continuous with the fourth winding start portion.
A method for manufacturing a choke coil. The bobbin that insulates the first core and the second core has a shape having a flange portion on the outer periphery of the end edge.
A method for manufacturing the choke coil according to claim 1. The core preparation step is a step of insulating an annular core with the bobbin and then cutting the annular core to form the first core and the second core.
A method for manufacturing the choke coil according to claim 1 or 2. The second core winding step is performed in a state in which an outer circumferential edge of one flange portion of the first core and an outer circumferential edge of one flange portion of the second core are brought close to each other.
A method for manufacturing the choke coil according to claim 2. a first A terminal is formed on one end edge of the first core part, and the first winding start portion and the fourth winding end portion are electrically connected to the first A terminal ;
a second B terminal is formed on the other end edge of the second core part, and the second winding end portion and the third winding start portion are electrically connected to the second B terminal.
A method for manufacturing the choke coil according to any one of claims 1 to 4. The first winding start portion and the fourth winding end portion are electrically connected to the first A terminal, and the second winding end portion and the third winding start portion are electrically connected to the second B terminal by welding or soldering.
A method for manufacturing the choke coil according to claim 5. a winding direction of the first winding as viewed from the first winding start portion side is opposite to a winding direction of the third winding,
The winding direction of the second winding as viewed from the second winding start portion side is opposite to the winding direction of the fourth winding.
A method for manufacturing the choke coil according to any one of claims 1 to 6. the winding direction of the first winding as viewed from the first winding start portion side is the same as the winding direction of the second winding as viewed from the second winding start portion side .
A method for manufacturing the choke coil according to claim 7 . the winding direction of the first winding as viewed from the first winding start portion side is opposite to the winding direction of the second winding as viewed from the second winding start portion side .
A method for manufacturing the choke coil according to claim 7 . The winding is a stranded wire.
A method for manufacturing the choke coil according to any one of claims 1 to 9 . The butting step is performed by inserting an insulating spacer between at least one end edge of the first core and the second core.
A method for manufacturing a choke coil according to any one of claims 1 to 10 . After the step of manufacturing a choke coil by the manufacturing method according to any one of claims 1 to 11 ,
A step of coating the obtained choke coil with a resin is included.
Manufacturing method for choke coil products.

Images