JP7536600B2 - Reactor - Google Patents

Description

The present invention relates to a reactor and a method for manufacturing a reactor.

A reactor is a passive element that has a coil and a core, and converts electrical energy into magnetic energy, which is then stored and released. Reactors are used in a wide variety of applications. Typical reactors include boost reactors, series reactors, parallel reactors, current limiting reactors, starting reactors, shunt reactors, neutral point reactors, and arc suppression reactors.

Boost reactors are incorporated into on-board boost circuits, such as those used in the drive systems of hybrid and electric vehicles. Series reactors are connected in series to motor circuits to limit the current during short circuits. Parallel reactors stabilize the current sharing between parallel circuits. Current-limiting reactors limit the current during short circuits and are connected to them. Starting reactors are connected in series to motor circuits that protect the machine and limit the starting current. Shunt reactors are connected in parallel to transmission lines to compensate for leading reactive power and suppress abnormal voltages. Neutral point reactors are connected between the neutral point and the ground to limit the ground fault current that flows in the event of a ground fault in the power system. Arc-suppression reactors automatically extinguish the arc that occurs when a single-line ground fault occurs in a three-phase power system.

In this reactor, the core is coated with a core coating resin, and the coil is attached to the core via the core coating resin. In addition, in the reactor body, which is composed of the core and coil, at least the coil is coated with molded resin. The core coating resin and molded resin provide insulation between the core and coil and between the coil and external members, and also protect the core and coil from direct physical contact, for example to prevent the enamel coating of the coil from being torn.

For molded resin, injection molding is often used, in which the reactor body is placed in a mold and resin is injected into the mold. For example, there is a reactor in which some areas of the coil are not covered with resin, leaving them exposed. By exposing part of the coil, the condition of the coil can be visually confirmed and the heat dissipation of the coil can be ensured. In such reactors, a mold is pressed against the surface of the coil, or a frame is pressed against the surface of the coil, to prevent the resin from entering the areas that are to be exposed (see, for example, Patent Documents 1 to 3).

The coil is made into a cylindrical shape by winding a conductive wire in a spiral shape while shifting the winding position for each turn along the winding axis, and has an outer shape in which four flat surfaces and four curved surfaces are arranged alternately. For reasons of manufacturing precision, the surface of the coil is not necessarily smooth, and there are twists on the surface of the coil. Therefore, even if a mold or frame is tried to be closely attached to the coil, there is a risk of a gap occurring between the mold or frame and the surface of the coil. If this happens, resin may seep in through this gap and cause burrs to form on the surface that is to be exposed.

To address this issue, a mold or frame is pressed firmly against the coil surface to straighten out any unevenness or twists on the coil's surface. The coil is pressed through a frame because pressing the coil too hard with a mold to straighten out the unevenness and twists could damage the coil, for example tearing the enamel coating.

Here, a linked coil may be arranged in the reactor. In order to obtain a high inductance value in the large current region, the linked coil is formed by forming two coils in parallel and linking them so that the currents flowing through both coils are in the opposite directions. This linked coil may be formed from a single conductive wire. That is, the first coil is formed using one side region of a single conductive wire, and the second coil is formed using the other side region of the same conductive wire. The remaining conductive wire portion sandwiched between the areas used to form the two coils becomes the linking portion that links the two coils (see, for example, Patent Document 4).

When two separate coils are installed in a reactor, four terminals are required, which increases the material costs of the reactor. Furthermore, when two separate coils are connected, the ends of the two separate coils need to be welded, which increases the amount of work required. On the other hand, connected coils only require two terminals, and there is no need to weld the ends of the two coils.

Patent No. 5869518 JP 2015-130410 A JP 2018-011019 A Patent No. 4812641

The conductive wire used to make coils is rectangular wire. One method of winding a coil is edgewise winding, in which the conductive wire is wound so that the wide surface of the wire extends in a direction perpendicular to the coil's winding axis. Edgewise winding has the advantage that the coil's winding axis direction can be shortened for the same number of turns compared to flatwise winding.

In linked coils, when rectangular wire is used as the conductive wire and edgewise winding is used as the winding method, the connecting portion that connects the two coils extends perpendicular to the winding axis, and when it is stretched straight from the end of each coil toward the end of the other coil, the wide surface expands perpendicular to the winding axis. On the other hand, when forming the molded resin, in order to prevent resin leakage, the surface of the coil is pressed firmly with a mold or frame to correct unevenness and twists on the coil surface, and the direction in which this mold or frame presses the coil is also perpendicular to the winding axis.

If the connecting part of the linked coils is not flexible to a certain extent in the direction in which the mold or frame presses against the coil surface, the force will not be transmitted to the coil, and the unevenness or twists on the coil surface cannot be corrected. However, the connecting part has a wide surface that runs along the direction in which the mold or frame presses against the coil surface. When considering the force pressing against one of the coils, the connecting part can be regarded as a cantilever beam with the end of that coil as the force point. The second moment of area of this connecting part is proportional to the product of the cube of the width of the wide surface and the width of the narrow surface.

Therefore, in a reactor that uses a linked coil in which a single conductive wire is wound edgewise, the linking portion acts as a strong beam, which reduces the effect of correcting unevenness and twists on the coil's surface. This means that when the molded resin is formed, resin leaks between the coil and the mold or frame, and it is impossible to eliminate the risk of burrs forming on the exposed surface.

The present invention was made to solve the above problems, and its purpose is to provide a reactor and a manufacturing method thereof in which burrs are suppressed even when a linked coil is used.

In order to solve the above-mentioned problems, a reactor of the present invention includes a reactor body including a core and a linked coil, and a molded resin that covers at least the linked coil of the reactor body, wherein the linked coil is wound by edgewise winding at a plurality of spaced apart locations of a single conductive wire, and includes at least a first coil, a second coil, and a linking portion that links the first coil and the second coil, and the first coil and the second coil are wound with their winding axes parallel to each other and are wound in a direction perpendicular to the winding axis. the first coil and the second coil are arranged side by side, the core is annular body having parallel legs on which the first coil and the second coil are attached and a yoke portion connecting the legs, the reactor body has a core-coating resin body having a leg covering portion that covers the legs and a yoke covering portion that covers the yoke portion, and the connecting portion extends between the first coil and the second coil and is bent toward the yoke covering portion so that a wide surface of the connecting portion falls in a direction parallel to the winding axis and is not in contact with a surface of the yoke covering portion .

According to the present invention, it becomes easier to correct unevenness and twists in the coils in the linked coils when molding the molding resin, and the occurrence of burrs is suppressed.

FIG. 2 is a perspective view of a reactor body. 4A and 4B are perspective views showing a core portion, in which FIG. 4A shows a core inside the core portion, and FIG. 4B shows a core coating resin outside the core portion. FIG. 2 is a first perspective view of a linked coil. FIG. 2 is a second perspective view of the linked coil. 1A and 1B are perspective views showing the state in which the first coil and the second coil are held down by the first plate and the second plate, where (a) shows the first plate side and (b) shows the second plate side. 4 is a cross-sectional view taken along a direction perpendicular to the winding axis, showing a state in which the first coil and the second coil are held down by the first plate and the second plate. FIG. FIG. 2 is a perspective view showing a reactor in which a reactor body is covered with a molded resin. FIG. 4 is an enlarged side perspective view of a connecting portion and a yoke covering portion. FIG. 4 is a partial enlarged view of a first plate body.

A reactor and a manufacturing method thereof according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing the configuration of a reactor body 6. The reactor body 6 is used as a boost reactor incorporated in an in-vehicle boost circuit, and is also used as a series reactor, parallel reactor, current limiting reactor, starting reactor, shunt reactor, neutral point reactor, arc suppression reactor, etc. This reactor body 6 includes a molded core 3 and a linked coil 1.

The linked coil 1 is attached to the molded core 3. This molded core 3 is an annular body that forms a closed magnetic circuit and passes the magnetic flux generated by the linked coil 1 with a magnetic permeability higher than that of a vacuum. The molded core 3 has a core 31 shown in FIG. 2(a). The core 31 is a magnetic body such as a ferrite core, a laminated steel plate, a powder magnetic core, or a metal composite, and a metal composite core is a core made by kneading and molding magnetic powder and resin.

The core 31 has a ring shape with two legs 311 on which the linked coil 1 is attached and a yoke portion 312 connecting the two legs 311. The core 31 is formed into a ring shape by, for example, butting the ends of two U-shaped blocks together and joining them. The joint end faces of the U-shaped blocks may be glued together with an adhesive or may be fixed by wrapping tape around them. A gap may be arranged within the U-shaped block to increase the magnetic resistance of the core 31.

As shown in FIG. 2(b), the molded core 3 is provided with a core coating resin 32. The core coating resin 32 is a molded product that maintains a certain shape, and coats the core 31. The linked coil 1 is wound around the core 31 via the core coating resin 32. This core coating resin 32 insulates the linked coil 1 fitted into the core 31 from the core 31. The core coating resin 32 is made of, for example, epoxy resin, unsaturated polyester resin, urethane resin, BMC (Bulk Molding Compound), PPS (Polyphenyl Sulfide), PBT (Polybutylene Terephthalate), or a composite of these.

This core coating resin 32 has a ring shape that follows the shape of the core 31 and includes a leg coating portion 321 that covers the two legs 311 and a yoke coating portion 322 that covers the yoke portion 312. The core coating resin 32 coats the core 31 by placing both U-shaped blocks of the core 31 in a mold and injection molding the resin. The mold core 3 may be an annular shape with two legs 311, a θ shape with three legs 311, or a shape with four or more legs 311 and a series of ring shapes.

Returning to FIG. 1, the linked coil 1 is a cylindrically wound body of conductive wire 10 such as enamel-coated copper wire, through which current flows and generates magnetic flux according to the number of turns. In order to obtain a high inductance value in the high current region, the linked coil 1 is formed by forming multiple coils in parallel and connecting the coils so that the currents flowing in both coils are in the opposite directions. For example, the linked coil 1 includes a first coil 11 and a second coil 12. The first coil 11 and the second coil 12 are arranged along an arrangement direction 13B that is perpendicular to the winding axis 13A with their winding axes 13A parallel to each other. The first coil 11 and the second coil 12 are then fitted into the two legs 311 of the molded core 3 via the leg covering parts 321 of the core covering resin 32.

The first coil 11 and the second coil 12 are connected by a connecting portion 2 drawn out from both end faces, and lead wires 11b and 12b are drawn out to the other end faces for current input and output with the outside. When a current flows through lead wires 11b and 12b in such a linked coil 1, the linked coil 1 generates magnetic flux according to the number of turns. The mold core 3 forms a closed magnetic circuit and passes the magnetic flux generated by the linked coil 1 with a magnetic permeability higher than that of a vacuum. Therefore, the reactor body 6 is an electromagnetic component that converts electrical energy into magnetic energy and stores and releases it.

Here, the connecting portion 2 extends between the first coil 11 and the second coil 12, and is bent so as to fall toward the surface 323 of the yoke covering portion 322 of the core covering resin 32. The detailed configuration of such a connecting coil 1 is shown in Figures 3 and 4.

Figures 3 and 4 are perspective views of the linked coil 1 from each direction. As shown in Figures 3 and 4, the body 11a and the body 12a of the linked coil 1 are wound bodies formed by winding the conductive wire 10 in a spiral shape along the winding axis 13A while shifting the winding position for each turn. The first coil 11 and the second coil 12 are spiral edgewise coils. The spiral edgewise coil is formed by winding the conductive wire 10 so that the wide surface 26a of the rectangular conductive wire 10 extends in the direction perpendicular to the winding axis 13A and the narrow surface 26b extends along the winding axis 13A.

The first coil 11, the second coil 12, and the connecting portion 2 are formed by forming the same single conductive wire 10. The first coil 11 is formed by winding the first winding range 10a of the single conductive wire 10. The second coil 12 is formed by winding the second winding range 10b opposite the first winding range 10a of the single conductive wire 10. The third connecting range 10c between the first winding range 10a and the second winding range 10b of the single conductive wire 10 is formed into the connecting portion 2.

The connecting portion 2 includes an excess portion 22 extending from the end 11c of the first coil 11 as a base end, an excess portion 22 extending from the end 12c of the second coil 12 as a base end, and a wire section 21 connecting the two excess portions 22. The wire section 21 extends across the first coil 11 and the second coil 12, connecting the two excess portions 22. The wire section 21 has the same length as the end-to-end distance 13C, which is the linear distance between the end 11c of the first coil 11 and the end 12c of the second coil 12.

The base end side of the excess length 22 extending from the first coil 11 is pulled out in a direction perpendicular to the winding axis 13A and in a direction different from the direction of the end 12c of the second coil 12. The excess length 22 has a bent portion 23 in the middle, and the overhead line portion 21 side is bent from the middle of the excess length 22 toward the yoke portion 312 (hereinafter referred to as the yoke side 24), which is the side opposite the body 11a of the first coil 11 and the body 12a of the second coil 12. The tip of the excess length 22 extending from the first coil 11 is connected at a right angle to the overhead line portion 21.

Similarly, the base end side of the excess length 22 extending from the second coil 12 is pulled out in a direction perpendicular to the winding axis 13A and in a direction different from the direction of the end 11c of the first coil 11. This excess length 22 has a bent portion 23 in the middle, and the overhead line portion 21 side from the middle of the excess length 22 is bent along the winding axis 13A toward the yoke side 24 on the opposite side to the body 11a of the first coil 11 and the body 12a of the second coil 12. The tip of the excess length 22 extending from the second coil 12 is connected at a right angle to the overhead line portion 21.

In general, starting from the first coil 11 and tracing the connecting portion 2, the excess portion 22 is first pulled out from the end 11c of the first coil 11 in a direction perpendicular to the winding axis 13A and in a direction different from the direction of the end 12c of the second coil 12. The excess portion 22 is bent at the bending portion 23 toward the yoke side 24 along the winding axis 13A. The end of the excess portion 22 is then connected at a right angle to the end of the overhead line portion 21.

The overhead line section 21 extends from the body 11a of the first coil 11 and the body 12a of the second coil 12 to a position separated along the winding axis 13A. The overhead line section 21 extends perpendicular to the winding axis 13A toward the second coil 12 by an end-to-end distance 13C, which is the linear distance between the end 11c of the first coil 11 and the end 12c of the second coil 12. The end of the overhead line section 21 reaches a position where it overlaps with the end 12c of the second coil 12 in the direction of the winding axis 13A.

The excess length 22 connected to the second coil 12 extends from the end of the wire section 21 along the winding axis 13A in a direction approaching the body 12a of the second coil 12. This excess length 22 is bent at the bending section 23 in a direction perpendicular to the winding axis 13A, and reaches the end 12c of the second coil 12 from a direction different from the direction of the end 11c of the first coil 11.

As shown in FIG. 1, such a linked coil 1 is attached to a molded core 3. Then, the linking portion 2 is bent so as to fall toward the surface 323 of the yoke covering portion 322 of the core covering resin 32. The linked coil 1 is formed by winding a rectangular conductive wire 10 by edgewise winding. Therefore, the wide surface 26a of the hanging portion 21 of the bent linked portion 2 extends parallel to the winding axis 13A, and the narrow surface 26b is perpendicular to the winding axis 13A. That is, when the linked coil 1 is covered with resin, the narrow surface 26b of the hanging portion 21 of the linked coil 2 is aligned in the direction in which the first coil 11 and the second coil 12 are pushed in order to correct the twists and unevenness of the first coil 11 and the second coil 12 of the linked coil 1. The wide surface 26a of the hanging portion 21 extends in a direction perpendicular to the pushing direction.

Figure 5 is a perspective view showing the state in which the first coil 11 and the second coil 12 are held down by the first plate 41 and the second plate 42, (a) showing the first plate 41 side and (b) showing the second plate 42 side. As shown in Figure 5, after the linked coil 1 and the molded core 3 are assembled, the first coil 11 and the second coil 12 are sandwiched between the first plate 41 and the second plate 42, which are made of insulating resin. In addition, a sensor 5 such as a thermistor that detects physical quantities such as the temperature of the reactor body 6 is placed in the gap between the first coil 11 and the second coil 12.

The first plate 41 is placed on the upper surface 14a, and the second plate 42 is placed under the first coil 11 and the second coil 12 so as to be in contact with the lower surface 14b. The first coil 11 and the second coil 12 have an outer shape in which four curved surfaces and four flat surfaces parallel to the winding axis 13A are alternately connected. Of the four flat surfaces, one that is parallel to the arrangement direction 13B of the first coil 11 and the second coil 12 is called the upper surface 14a, and the back side of this upper surface 14a is called the lower surface 14b.

The first plate 41 is a solid flat plate whose entire plane is filled. On the other hand, the second plate 42 is a frame having an exposure window 42a inside. This second plate 42 exposes a portion of the underside 14b of the first coil 11 and the second coil 12 from the exposure window 42a, making it suitable for dissipating heat from the first coil 11 and the second coil 12. In addition, the state of the first coil 11 and the second coil 12 can be seen from the exposure window 42a of the second plate 42.

As shown in FIG. 6, a force is applied to the first coil 11 and the second coil 12 in the direction from the upper surface 14a to the lower surface 14b via the first plate 41. The first coil 11 and the second coil 12 are pressed against the second plate 42. At this time, the direction of the force applied to the first coil 11 and the second coil 12 is the direction in which the narrow surface 26b of the wire section 21 of the connecting part 2 expands. The direction in which the wide surface 26a of the wire section 21 of the connecting part 2 expands is perpendicular to the direction of this force.

The second moment of area of the wire section 21 is then proportional to the product of the cube of the width of the narrow surface 26b and the width of the wide surface 26a. In contrast, the second moment of area of the wire section 21 before being bent at the bend 23 is proportional to the product of the cube of the width of the wide surface 26a and the width of the narrow surface 26b. That is, in this reactor body 6, the connecting section 2 is bent so that the wide surface 26a of the connecting section 2 falls in a direction parallel to the winding axis 13A, making it easier to apply force to the first coil 11 and the second coil 12.

This makes it easier to eliminate unevenness and twists in the first coil 11 and the second coil 12. In other words, the first coil 11 and the second coil 12 can be easily pressed against the second plate 42, eliminating gaps between the first coil 11 or the second coil 12 and the second plate 42.

Because the first plate 41 is a solid flat plate, it has higher rigidity than the second plate 42 and is suitable as a pressing plate for eliminating unevenness and twisting of the first coil 11 and the second coil 12. This first plate 41 can apply a large force to the first coil 11 and the second coil 12. In this reactor body 6, the first plate 41 can apply a large force to the first coil 11 and the second coil 12, and the bending of the connecting portion 2 can transmit a large force to the first coil 11 and the second coil 12.

As shown in FIG. 7, resin is injected into the mold, and the linked coil 1, including the linking portion 2, is covered with molded resin 43. When the resin is injected into the mold, the first coil 11 and the second coil 12 are pressed against the second plate 42 by the first plate 41. Therefore, the gap between the second plate 42 and the first coil 11 and the second coil 12 is eliminated by correcting the unevenness and twists of the first coil 11 and the second coil 12, and the occurrence of burrs in the exposure window 42a is suppressed.

The first plate 41, the second plate 42, and the molded resin 43 are made of materials such as epoxy resin, unsaturated polyester resin, urethane resin, BMC (Bulk Molding Compound), PPS (Polyphenyl Sulfide), PBT (Polybutylene Terephthalate), or a composite of these.

Here, FIG. 8 is an enlarged perspective side view of the connecting portion 2 and the yoke covering portion 322, with the molded resin 43 removed from the drawing. As shown in FIG. 8, the bent portion 23 of the connecting portion 2 is bent 90 degrees, and the overhead line portion 21 and the surface 323 of the yoke covering portion 322 are parallel to each other. However, the bent portion 23 is disposed at a position separated in the height direction from the surface 323 of the yoke covering portion 322, and the overhead line portion 21 and the yoke covering portion 322 have a facing surface distance 33D of 0.5 mm to 5.0 mm.

The gap between the overhead line portion 21 and the yoke covering portion 322 allows room for the overhead line portion 21 to bend when the first plate 41 presses the first coil 11 and the second coil 12. However, if the distance between the opposing surfaces 33D is more than 5.0 mm, sink marks and voids will occur in the molded resin 43 filled between the overhead line portion 21 and the yoke covering portion 322. However, if the distance between the opposing surfaces 33D is 5.0 mm or less, the occurrence of sink marks and voids can be suppressed. Therefore, it is possible to suppress the enamel coating from peeling off at the sink marks and voids where the overhead line portion 21 is exposed, resulting in loss of insulation.

Furthermore, if the distance between the opposing surfaces 33D is more than 5.0 mm, there is a risk that the overhead line portion 21 will be agitated by the resin that has forcefully entered the gap between the overhead line portion 21 and the yoke covering portion 322. However, if the distance between the opposing surfaces 33D is 5.0 mm or less, the force that agitates the overhead line portion 21 will be weakened, and the connection portion 2 can be prevented from being exposed from the molded resin 43.

Returning to FIG. 7, the molded resin 43 covering the connecting portion 2 has one hole 431a and two holes 431b formed therein, exposing the connecting portion 2. The holes 431a and 431b are traces of a pin body (not shown) that pressed down the connecting portion 2 when the molded resin 43 was formed. The hole 431a is a trace of pressing down the overhead line portion 21, and the hole 431b is a trace of pressing down the excess length portion 22. Even when the opposing surface distance 33D is 0.5 mm or more and 5.0 mm or less, pressing down the connecting portion 2 can further reduce the risk that the resin that has entered between the overhead line portion 21 and the yoke covering portion 322 will fan the overhead line portion 21, causing the connecting portion 2 to be exposed from the molded resin 43, and further prevent damage to the enamel coating of the connecting portion 2.

As described above, this reactor is manufactured by including a coil creation process and a molding process. In the coil creation process, a single conductive wire 10 is wound edgewise at multiple separated locations to create a linked coil 1. In detail, the linked coil 1 is created as follows. That is, a first coil 11 and a second coil 12 adjacent to the first coil 11 are created. The first coil 11 and the second coil 12 are arranged with their winding axes 13A parallel to each other. The connecting portion 2 connecting the first coil 11 and the second coil 12 is extended between the first coil 11 and the second coil 12.

The coil fabrication process includes a bending process in which the connecting portion 2 is bent so that the wide surface 26a of the connecting portion 2 is in a direction parallel to the winding axis 13A. After the connecting coil 1 is attached to the core 31, at least the connecting coil 1 is coated with resin in the subsequent molding process while correcting the twists of the first coil 11 and the second coil 12.

As a result, the connected coil 1 of the reactor body 6 has a connecting portion 2 that extends between the first coil 11 and the second coil 12 and is bent so that the wide surface 26a of the connecting portion 2 is in a direction parallel to the winding axis 13A. This shortens the projected length of the connecting portion 2 along the direction perpendicular to the winding axis 13A, making it easier to apply force to the first coil 11 and the second coil 12 from the direction perpendicular to the winding axis 13A. This makes it easier to correct unevenness and twists in the first coil 11 and the second coil 12, and makes it less likely that burrs will occur when molding the molded resin 43.

In addition, because the connecting portion 2 is bent so as to fall in a direction parallel to the winding axis 13A, the connecting portion 2 does not protrude from the upper surfaces 14a of the first coil 11 and the second coil 12. As a result, the connecting portion 2 does not interfere with the mold, and the entire upper surfaces 14a of the first coil 11 and the second coil 12 can be pressed with the mold. Therefore, this also makes it easier to apply force to the first coil 11 and the second coil 12.

The connecting portion 2 is bent 90 degrees until the wide surface 26a of the wire section 21 is parallel to the winding axis 13A, and is brought close to being parallel to the surface 323 of the yoke covering portion 322, but this is not limited to this. If the projected length of the connecting portion 2 along the direction perpendicular to the winding axis 13A is shortened, it becomes easier to apply force to the first coil 11 and the second coil. However, if the wide surface 26a of the wire section 21 is bent 90 degrees until it is parallel to the winding axis 13A, the second moment of area is minimized, and the effect of correcting unevenness and twists in the first coil 11 and the second coil 12 is improved. It is preferable to bend at least 45 degrees or more.

Although the connecting portion 2 is bent toward the yoke side 24, it may be bent in a direction overlapping the body 11a of the first coil 11 and the body 12a of the second coil 12 in order to make it easier to apply force to the first coil 11 and the second coil 12. However, by bending the connecting portion 2 toward the yoke side 24, the reactor body 6 can be made lower in height in the height direction perpendicular to the winding axis 13A. In addition, compared to bending the connecting portion 2 toward the body 11a or body 12a, the bending tool does not interfere with the side of the body 11a of the first coil 11 and the body 12a of the second coil 12. Therefore, the position of the bending tool can be freely set, and the bending accuracy is improved. In addition, the first coil 11 and the second coil 12 are not scratched or damaged by the tool.

In addition, in the bending process of the connecting portion 2, the connecting portion 2 is bent toward the yoke covering portion 322 so as not to come into contact with the surface 323 of the yoke covering portion 322. This prevents the connecting portion 2 from being supported by the yoke covering portion 322 and becoming unable to bend when a force is applied to the first coil 11 and the second coil 12 to correct unevenness or twisting.

However, the distance 33D between the opposing surfaces of the connecting portion 2 and the yoke covering portion 322 is set to 0.5 mm or more and 5.0 mm or less. This reduces the risk of sink marks or voids occurring in the molded resin 43 filled between the overhead line portion 21 and the yoke covering portion 322. This prevents physical contact with the overhead line portion 21 through sink marks or voids, which can cause damage such as peeling off of the enamel coating.

The molded resin 43 also has multiple holes 431a, 431b through which the wide surface 26a of the connecting portion 2 is exposed. This allows the wide surface 26a of the connecting portion 2 to be pressed with a pin before being molded with resin in the molding process. Therefore, even if there is a gap between the overhead line portion 21 of the connecting portion 2 and the yoke covering portion 322, the connecting portion 2 is less likely to be blown up and deformed, resulting in exposure from the molded resin 43. Therefore, the connecting portion 2 is protected by the molded resin 43, and the risk of, for example, the enamel coating being damaged is reduced.

The first plate 41, which presses the first coil 11 and the second coil 12 in the molding process, is a solid flat plate with the entire plane filled. This first plate 41 has high rigidity and can strongly press the first coil 11 and the second coil 12. This makes it easier to correct unevenness and twists in the first coil 11 and the second coil 12. If the correction of unevenness and twists is to be made easier only by the bending action of the connecting portion 2, the first plate 41 may be a frame body like the second plate 42.

In the molding process, the first coil 11 and the second coil 12 are pressed through the first plate 41, but this is not limited to the above. A mold may be pressed against the first coil 11 and the second coil 12 to correct any irregularities or twists in the first coil 11 and the second coil 12, and bending the connecting portion 2 makes this correction easier.

In addition, in this reactor, a second plate 42 having an exposure window 42a is installed, and an example is given of burrs being generated in the exposure window 42a due to gaps being generated between the first coil 11 or second coil 12 and the second plate 42. This is not limited to this, and bending the connecting portion 2 can be used to deal with situations in which gaps are generated in the areas on the surfaces of the first coil 11 and second coil 12 where burrs are to be removed.

Here, in this reactor, the connecting portion 2 is configured to be composed of an overhead line portion 21 and an excess portion 22. This connecting portion 2 not only electrically connects the first coil 11 and the second coil 12, but is also an offset portion that absorbs wire feed errors during the formation of the first coil 11 and the second coil 12. The excess portion 22 is made longer in advance to absorb wire feed errors during the formation of the first coil 11 and the second coil 12, and the juxtaposition positions of the first coil 11 and the second coil 12 are adjusted using the length of the excess portion 22. In other words, the excess portion 22 is the remainder after absorbing wire feed errors during the formation of the first coil 11 and the second coil 12.

The connecting portion 2 is not limited to this, and since the excess length portion 22 is not taken longer in advance, it may not function as an offset portion and may only electrically connect the first coil 11 and the second coil 12. In other words, the connecting portion 2 may include a wire portion 21 that starts at the end 11c of the first coil 11 and ends at the end 12c of the second coil 12.

Even in the case of a connecting part 2 that only electrically connects the first coil 11 and the second coil 12, if the wide surface 26a stands perpendicular to the winding axis 13A, it becomes difficult to apply force to the first coil 11 and the second coil 12 to correct unevenness or twisting. On the other hand, even in the case of such a connecting part 2, it becomes easier to apply force to the first coil 11 and the second coil 12 by bending the wide surface 26a of the connecting part 2 so that it falls in a direction parallel to the winding axis 13A.

The bend 23 that bends the connecting portion 2 toward the yoke covering portion 322 is not limited to the excess length 22. The connecting portion 2 may be bent by bending the overhead line portion 21 along the length of the overhead line portion 21, or may be bent at the boundary portion 25 (see Figures 3 and 4) where the excess length 22 bends with the overhead line portion 21. However, if the overhead line portion 21 is bent along the length, the area requiring bending will be elongated, and the boundary portion 25 has already been deformed by edgewise bending to extend the overhead line portion 21 from the end of the excess length 22. Therefore, it is preferable to create the bend 23 in the excess length 22, since it is easier to perform bending with high precision.

The above embodiments of the present invention are presented as examples, and the present invention is not limited to the above embodiments. The above embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. The embodiments and their modifications are included in the scope of the present invention.

For example, the first plate 41 functions as a covering for the first coil 11 and the second coil 12, and as a pressing body for the first coil 11 and the second coil 12. In addition, the first plate 41 can also function as a positioning member for the lead wires 11b and 12b. FIG. 9 is a partially enlarged view of the first plate 41 arranged on the second coil 12. The first plate 41 arranged on the first coil 11 has the same shape and function as the first plate 41 arranged on the second coil 12, so a description thereof will be omitted.

As shown in FIG. 9, the first plate 41 is disposed so as to overlap each of the lead wires 12b. The first plate 41 has a clamping portion 411 formed at a position overlapping the lead wire 12b. The clamping portion 411 has a hoe-shaped shape, clamps the lead wire 12b, and corrects the extension of the lead wire 12b.

A space 412 is formed at a position overlapping with the lead-out base end 121b of the lead-out wire 12b. When the lead-out wire 12b is drawn out from the second coil 12, the lead-out base end 121b is bent in the drawing direction. As a result, the lead-out base end 121b is curved, and a precision error occurs in the size of the lead-out base end 121b. The space 412 is formed large to prevent a situation in which the first plate body 41 cannot be placed or cannot be clamped by the clamping portion 411 due to contact with the lead-out base end 121b having a precision error.

1 connected coil 10 conductive wire 10a first winding range 10b second winding range 10c third connected range 11 first coil 11a body 11b lead wire 11c end 12 second coil 12a body 12b lead wire 121b lead base end 12c end 13A winding shaft 13B arrangement direction 13C end-to-end distance 14a upper surface 14b lower surface 2 connecting portion 21 wire portion 22 excess length portion 23 bending portion 24 yoke side surface 25 boundary portion 26a wide surface 26b narrow surface 3 molded core 31 core 311 leg portion 312 yoke portion 32 core coating resin 321 leg coating portion 322 yoke coating portion 323 surface 33D opposing surface distance 41 first plate 411 clamping portion 412 space portion 42 Second plate 42a Exposure window 43 Molded resin 431a Hole 431b Hole 5 Sensor 6 Reactor body

Claims (8)

A reactor body including a core and a coupled coil;
a mold resin that covers at least the connected coil in the reactor body;
Equipped with
the linked coil is formed by edgewise winding a single conductive wire at a plurality of spaced apart locations, and includes at least a first coil, a second coil, and a linking portion linking the first coil and the second coil;
The first coil and the second coil are arranged in a direction perpendicular to the winding axes with their winding axes parallel to each other,
the core is an annular body having parallel legs on which the first coil and the second coil are attached and a yoke portion connecting the legs,
the reactor body includes a core-coating resin body having a leg covering portion that covers the leg portion and a yoke covering portion that covers the yoke portion,
the connecting portion extends between the first coil and the second coil, is bent toward the yoke covering portion so that a wide surface of the connecting portion falls in a direction parallel to the winding axis , and is not in contact with a surface of the yoke covering portion ;
A reactor characterized by the above. the connecting portion is bent 90 degrees, and the wide surface is parallel to the winding axis;
The reactor according to claim 1 . The distance between the opposing surfaces of the connecting portion and the yoke covering portion is 0.5 mm or more and 5.0 mm or less.
The reactor according to claim 1 or 2 , a first plate body and a second plate body arranged to sandwich the first coil and the second coil,
the molding resin covers the first plate and the second plate except for the first plate,
one of the first plate and the second plate is a pressing plate that presses the first coil and the second coil when the molding resin is formed;
The reactor according to any one of claims 1 to 3 , The pressing plate is a solid flat plate whose entire plane is filled;
The reactor according to claim 4 . The other of the first plate body and the second plate body, which is not the pressing plate, is a frame body;
The reactor according to claim 4 or 5 , the molding resin has a plurality of holes through which the wide surface of the connecting portion is exposed;
The reactor according to any one of claims 1 to 6 , The connecting portion is
a wire portion that is stretched between the first coil and the second coil;
an excess portion that is drawn out from an end of the first coil and the second coil and connected to both ends of the overhead line portion;
having
the excess portion is bent so that the wide surface of the connecting portion is inclined in a direction parallel to the winding axis;
The reactor according to any one of claims 1 to 7 ,

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