JP6277761B2 - Reactor manufacturing method and reactor - Google Patents

Description

  The present invention relates to a reactor manufacturing method and a reactor, and more particularly to a reactor manufacturing method in which a layer made of a curable resin is formed on the surface of a strand, and such a reactor.

  A reactor including a coil is used for a power conversion device such as a DC-DC converter mounted on a vehicle such as a hybrid vehicle, an electric air vehicle, or a fuel cell vehicle. The structure of the reactor is disclosed in Patent Document 1, for example. FIG. 6 shows a cross-sectional view of a conventional general reactor 90 as described in Patent Document 1. In the reactor 90, a coil 91 inserted through a magnetic core (core) 92 is accommodated in a case made up of a side wall portion 93 and a bottom plate portion 94. The space inside the case is filled with casting resin (sealing resin) 95. The casting resin 95 has a role of maintaining insulation of the coil 91 and a role of promoting cooling of the coil 91. The casting resin 95 penetrates between the coil turns of the coil 91 and has an effect not only on the insulation of the entire coil 91 but also on the insulation between the coil turns.

JP 2012-253384 A

  In the conventional general reactor 90, the casting resin 95 filled in the case may be cracked due to a temperature change or the like. Then, the function of the casting resin 95 as described above is not sufficiently performed. Therefore, there is room to consider manufacturing a reactor that can insulate and cool the coil 91 without using the casting resin 95.

  However, when the casting resin 95 is not used, the coil 91 vibrates due to the vibration of the vehicle on which the reactor 90 is mounted, and friction is generated between the coil turns. If friction occurs between the coil turns, the insulation coating made of enamel or the like formed on the outer periphery of the wire of the coil 91 may be worn, and insulation between the coil turns may not be maintained.

  The problem to be solved by the present invention is a manufacturing method for manufacturing a reactor capable of suppressing the dielectric breakdown between coil turns due to vibration and cooling the coil without using a casting resin, And to provide such a reactor.

  In order to solve the above-described problems, a method for manufacturing a reactor according to the present invention includes a step of applying a curable resin in an uncured state to a part of the surface of a wire in which the surface of the conductor wire is covered with an insulating coating layer. The step of curing the applied curable resin, and the step of forming the coil by winding the wire while disposing the portion where the curable resin is disposed at a portion where adjacent coil turns are opposed to each other The gist of this is to continuously execute in this order.

  Here, it is preferable that the coil is a square coil, and the curable resin is disposed at least at a corner portion of the square coil.

  Further, the curable resin is disposed in a region relatively close to the central axis of the coil, and the portion where the strand is exposed without being covered with the curable resin is more than the region in which the curable resin is disposed. It is preferable to arrange in a region far from the central axis of the coil.

  And it is good to arrange | position the said curable resin discontinuously along the axial direction of the said strand.

  Or it is good to arrange | position the said curable resin continuously over the whole axial direction of the said strand.

  Moreover, it is preferable that the said curable resin has photocurability.

  The gist of the reactor according to the present invention is that it is manufactured by the manufacturing method according to the present invention as described above.

  If the manufacturing method of the reactor concerning the said invention is used, the coil which has arrange | positioned curable resin to the strand surface of the site | part which the adjacent coil turns mutually opposes can be manufactured, and a reactor can be comprised. Thereby, even when the entire coil receives vibration and vibration occurs between the coil turns, at least in the portion covered with the curable resin, the strands constituting each coil turn are not in direct contact with each other, Wear of the insulating coating layer due to friction between the coil turns is suppressed. Therefore, even when the coil receives vibration, the insulation between the coil turns is easily maintained. On the other hand, since the part which is not covered with the curable resin exists in the element wire constituting the coil, this part can be used for cooling the coil.

  And in the said manufacturing method, before winding a strand in a coil shape, since curable resin is arrange | positioned in the predetermined position of the strand surface, the structure which has arrange | positioned curable resin in the site | part between coil turns. Can be easily formed. In addition, it is easy to accurately control the part where the curable resin is disposed, and it is easy to reliably leave the part exposed without being covered with the curable resin. Furthermore, a coil as described above can be easily manufactured by continuously executing a step of applying an uncured curable resin to a strand, a step of curing, and a step of winding a strand to form a coil. can do.

  Here, when the coil is a square coil, if the curable resin is disposed at least at the corners of the square coil, the interval between the coil turns is narrow due to the difference in the dimensions of the outer peripheral surface and the inner peripheral surface of the coil. In the corners of a rectangular coil that is prone to wear and therefore wear of the insulation coating layer due to vibration, the presence of curable resin between the coil turns effectively suppresses dielectric breakdown between the coil turns due to vibration. Can do.

  Further, the curable resin is disposed in a region relatively close to the central axis of the coil, and the portion where the element wire is exposed without being covered with the curable resin is more centralized than the region in which the curable resin is disposed. When the coil is disposed in a region far from the coil, the interval between the coil turns tends to be narrowed, and accordingly, the curable resin is disposed in a region on the central axis side of the coil where the insulation coating layer is likely to be worn by vibration. Therefore, the dielectric breakdown between the coil turns can be more effectively suppressed.

  And, when disposing the curable resin discontinuously along the axial direction of the strand, the ratio of the area exposed without being covered with the curable resin is increased, so that the cooling efficiency of the coil is increased. Can do. In particular, by selecting a portion where the abrasion of the insulating coating layer is likely to occur and disposing the curable resin, it is possible to achieve both the effect of suppressing the dielectric breakdown between the coil turns and the cooling efficiency of the coil.

  Alternatively, in the case where the curable resin is continuously arranged over the entire axial direction of the strands, the curable resin is arranged in the entire region along the winding direction of the coil. The effect of suppressing destruction is particularly high. In addition, when winding the wire, it is not necessary to consider the matching relationship between the coil winding structure, such as the position of the corner of the square coil, and the position where the curable resin is disposed on the wire, The manufacturing process can be simplified.

  In addition, when the curable resin has photocurability, the curable resin can be cured in a short time by light irradiation after applying the curable resin in an uncured state. It is possible to prevent the curable resin from flowing out to a site other than the predetermined site where it is applied and curing. As a result, it becomes easy for the part coated with the curable resin and the part exposed without being coated to coexist as designed, and a coil having the desired dielectric breakdown suppression effect and cooling efficiency is manufactured. can do. In addition, since it takes only a short time to apply the uncured resin to the wire and to wind it into the coil shape, the coil can be manufactured at a high speed and the configuration of the manufacturing apparatus is simplified. be able to.

  The reactor concerning the said invention has a coil by which curable resin is arrange | positioned on the strand surface of the site | part where the adjacent coil turns mutually oppose. As a result, even when the entire coil receives vibration and vibration occurs between the coil turns, the wires constituting each coil turn are not in direct contact with each other, and the insulating coating layer is worn by friction between the coil turns. To be suppressed. Therefore, even when the coil receives vibration, the insulation between the coil turns is easily maintained. On the other hand, since the part which is not covered with the curable resin exists in the element wire constituting the coil, this part can be used for cooling the coil. And since curable resin is arrange | positioned on a strand in the elongate state before winding a coil, the site | part coat | covered with curable resin and the site | part exposed without being coat | covered with curable resin are Are coexisting with high precision. Thereby, suppression of dielectric breakdown and cooling efficiency are highly compatible. Moreover, since it is not necessary to use casting resin, the whole reactor is simplified and reduced in weight.

It is a perspective view which shows the coil which comprises the reactor concerning one Embodiment of this invention. It is sectional drawing which passes along the corner | angular part arrange | positioned diagonally along the central-axis direction of the said coil. It is the top view which extracted one coil turn of the said coil. In the coil concerning another example, it is the top view which extracted one coil turn, (a)-(c) has shown a different example, respectively. It is a schematic diagram which shows the manufacturing method of the reactor concerning one Embodiment of this invention. It is sectional drawing which shows the conventional general reactor (the hatching which shows a cross section is abbreviate | omitting suitably).

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[Reactor structure]
First, a reactor according to an embodiment of the present invention will be described. 1-3, the coil 10 which comprises the reactor concerning one Embodiment of this invention is shown.

  The coil 10 is formed by spirally winding an element wire 11 in which the outer periphery of a conductor wire 11a is covered with an insulating coating layer 11b. The coil 10 has an overall shape in which two straight portions 10a, 10a are aligned in the winding direction.

  The conductor wire 11a is made of metal such as copper or copper alloy, aluminum or aluminum alloy, for example. The insulating coating layer 11b is made of an enamel material typified by polyamideimide, for example. Moreover, as a shape of the strand 11, it is preferable that it is a flat wire from a viewpoint of raising the cooling property of the coil 10 and raising the density of winding. The coil 10 is preferably formed as a square coil having a shape obtained by rounding the corners of a prism, from the viewpoint of ease of fixing and the like.

  A magnetic core 20 is inserted into the hollow portion V of each linear portion 10 a of the coil 10. The magnetic core 20 has the same configuration as a known magnetic core, for example, similar to the magnetic core 92 shown in FIG. 6 in which core portions 92a made of a magnetic material and gap portions 92b made of a nonmagnetic material are alternately connected. Can be applied.

  The coil 10 in which the magnetic core 20 is inserted is appropriately fixed to a mounting surface such as a bottom plate (not shown), and input / output terminals, sensors, and the like are attached thereto, and assembled as a reactor. Here, in the conventional reactor 90 shown in FIG. 6, the coil 91 is housed in a case made up of the bottom plate portion 94 and the side wall portion 93, and the casting resin 95 is filled in the space in the case. In the reactor, casting resin is not used. In other words, a member corresponding to the side wall portion 93 in FIG.

  The reactor according to the present embodiment is characterized in that an inter-turn resin layer 12 is disposed at a position between coil turns (each pitch of the spiral) of the wire 11 constituting the coil 10. That is, as shown in FIGS. 2 and 3, an inter-turn resin layer 12 made of an insulating curable resin (reactive resin) is formed on the surface of the strand 11 at a portion where each coil turn faces an adjacent coil turn. Is formed. The inter-turn resin layer 12 does not cover the entire surface of the strand 11 constituting the coil 10, and the coil 10 is not covered with the inter-turn resin layer 12, but the strand 11 (the insulating coating layer 11b). The exposed region coexists with the region covered with the inter-turn resin layer 12. Here, the bare wire 11 means that it is exposed to the ambient environment where the reactor is installed, such as the atmosphere, and is covered with a resin other than the inter-turn resin layer 12 such as a casting resin. It does not include the state. In FIG. 2, the inter-turn resin layer 12 is formed only on one surface of the strand 11, but may be formed on both surfaces. Or the resin layer 12 between turns may be arrange | positioned so that both the strands 11 which mutually oppose between adjacent coil turns may be contacted, and both strands 11 may be connected.

  Since the inter-turn resin layer 12 is formed in the portion of the coil 10 facing between the coil turns, the coil 10 receives vibration, and vibration between adjacent coil turns, that is, relative displacement between the coil turns occurs. However, at least at the part where the inter-turn resin layer 12 exists, the surfaces of the strands 11 are prevented from directly contacting each other between the coil turns.

  The vibration of the coil 10 is caused by the vibration of the vehicle on which the reactor is mounted. If the adjacent coil turns come into direct contact with each other due to this type of vibration and collide with each other to cause friction, the insulating coating layer 11b on the surface of the strand 11 may be worn. Then, the insulation between coil turns is destroyed, a short circuit (rare short) occurs, and the output characteristics of the reactor change. In addition, rapid heat generation occurs due to a large current flowing through the site where the short circuit occurs. The heat generation may affect other members arranged around the coil 10 such as melting of the solder part or peeling of the adhesive part, and may lead to stoppage of the vehicle while traveling or irreversible damage to the member. There is.

  In contrast, in the reactor according to the present embodiment, the inter-turn resin layer 12 is formed between the coil turns, and the strands 11 are not in direct contact between the coil turns. In the region covered with the inter-turn resin layer 12, the insulating coating layer 11b on the surface of the strand 11 is less likely to be worn. Therefore, short circuit between coil turns and generation of heat accompanying it are suppressed. Even when a large impact is applied to the coil 10, the insulating coating layer 11 b of the strand 11 is protected by the deformation or destruction of the inter-turn resin layer 12. Furthermore, particularly when the inter-turn resin layer 12 is disposed so as to come into contact with both of the strands 11 facing each other between adjacent coil turns and to connect both coil turns, the adjacent coil turns are Since the resin layer 12 is fixed to each other via the inter-turn resin layer 12 and the relative motion itself between the coil turns is limited, the effect of suppressing the dielectric breakdown between the coil turns is increased.

  On the other hand, the entire surface of the wire 11 constituting the coil 10 is not covered by the resin layer 12 between the coil turns, but is partially exposed, so that when the coil 10 generates heat when current is applied. In addition, cooling (heat radiation) can be performed through the exposed portion. That is, it is possible to achieve both suppression of dielectric breakdown between coil turns and securing of cooling performance.

  The inter-turn resin layer 12 may be made of any curable resin (reactive resin). Here, the curable resin is adopted because the curable resin generally does not easily soften or melt even if it receives heat, and even if the coil 10 generates heat, the insulation coating layer 11b wears between the coil turns. This is because the function of the inter-turn resin layer 12 that suppresses the above is maintained at a high level. Moreover, since the resin layer 12 between turns is formed in the desired site | part by apply | coating to the predetermined site | part of the strand 11 in an uncured state and making it harden | cure, it is easy to produce the structure where the other site | part was exposed. It is. Examples of the curing method include photocuring, heat curing, moisture curing, two-component reaction curing, and the like. A plurality of curing methods may be used in combination. As will be described later in the description of the manufacturing method of the coil 10, from the viewpoint of the simplicity of the manufacturing process and the precision of the arrangement of the inter-turn resin layer 12, the curable resin may have photo-curing properties (particularly, ultraviolet curable). preferable.

  The curable resin constituting the inter-turn resin layer 12 may be made of any resin type, such as silicone resin, acrylic resin, epoxy resin, urethane resin, polyamide resin, phenolic resin, unsaturated resin. Examples thereof include polyester resins and polyurea resins. These may be used alone or in combination of two or more. Furthermore, additives such as coloring pigments, viscosity modifiers, anti-aging agents, inorganic fillers, storage stabilizers, and dispersants may be added to the curable resin.

  As described above, the inter-turn resin layer 12 is formed on the surface of the strand 11 where the adjacent coil turns oppose, and an exposed portion that is not covered by the inter-turn resin layer 12 remains on the surface of the strand 11. As long as it is done, the inter-turn resin layer 12 has a width direction of the strand 11, that is, a direction orthogonal to the central axis C of the coil 10, and an axial direction of the strand 11 ( (Longitudinal direction), that is, it may be formed at any position along the winding direction of the coil 10. However, the arrangement shown in FIGS. 2 and 3 is preferred.

  Specifically, if attention is paid to the width direction of the wire 11, that is, the direction orthogonal to the central axis C of the coil 10, the inter-turn resin layer 12 is formed in an inner portion near the central axis C of the coil 10. It is desirable that Since the coil 10 has a structure in which the inner peripheral surface has a smaller cross-sectional shape than the outer peripheral surface, the strands 11 forming each coil turn are relatively outer as shown schematically in FIG. Is thin (thin) and the inside is thick (thick) (rolling thick). That is, the distance between the coil turns is narrower on the inner side than the outer side of the coil 10, and when the coil 10 receives vibration, the contact between the coil turns and the insulation by the inner side than the outer side of the coil 10. Wear of the coating layer 11b is likely to occur. Therefore, by disposing the inter-turn resin layer 12 between the coil turns of the inner portion of the coil 10, it is possible to more effectively suppress the dielectric breakdown due to wear of the insulating coating layer 11b than when the resin layer 12 is disposed on the outer portion. . In particular, when the strand 11 is a flat wire, the winding thickness tends to increase, so that the effect of disposing the inter-turn resin layer 12 on the inner portion is great. Further, when the inter-turn resin layer 12 is disposed on the inner portion of the coil 10, an exposed portion that is not covered with the inter-turn resin layer 12 is disposed relatively on the outer side. This is advantageous in increasing the efficiency of the system. In FIG. 3 (and FIGS. 4 and 5), the inter-turn resin layer 12 is shown slightly outside the inner peripheral edge of the coil 10 for easy understanding, but it is arranged so as to be in contact with the inner peripheral edge. Also good.

  On the other hand, when attention is paid to the axial direction of the element wire 11, that is, the direction along the winding direction of the coil 10, the inter-turn resin layer 12 can be formed in a region including the corner portion B in the rectangular coil 10. It is advantageous. This is because, in a square coil, the thickening of winding occurs at the corner B. In other words, as shown in FIG. 2 as a cross-sectional view passing through two corners B arranged diagonally, in the inner part of the corner B, the interval between the coil turns is narrow, and the insulation coating by vibration Wear of the layer 11b is likely to occur. Therefore, by disposing the inter-turn resin layer 12 at the corner B, the dielectric breakdown can be particularly effectively suppressed. In the example shown in FIG. 3, the inter-turn resin layer 12 includes four corner portions B and is formed over the entire region of the strand 11 in the axial direction.

  The ratio between the part where the inter-turn resin layer 12 is formed and the part which is exposed without being formed may be appropriately selected in consideration of the expected degree of vibration and the degree of heat generation of the coil 10. As the ratio of the region covered with the inter-turn resin layer 12 is increased, the effect of suppressing the dielectric breakdown between the coil turns due to vibration is enhanced, and as the ratio of the region covered with the inter-turn resin layer 12 is decreased, The efficiency of cooling (heat dissipation) is increased.

  As described above, in the coil 10 shown in FIG. 3, the inter-turn resin layer 12 is continuously formed over the entire region of the strand 11 in the axial direction. Thereby, the effect which suppresses the dielectric breakdown between the coil turns by vibration can be acquired largely.

  On the other hand, in the coils 10a to 10c according to the modified examples shown in FIGS. 4A to 4C, the inter-turn resin layer 12 is formed discontinuously (intermittently) along the axial direction of the strand 11. Has been. In these cases, the inter-turn resin layer 12 is not covered with the inter-turn resin layer 12 as compared with the case where the inter-turn resin layer 12 is continuously formed along the axial direction of the strand 11 as shown in FIG. The ratio of the exposed area is large, and the cooling efficiency of the coil can be increased. Among the coils 10a to 10c in FIGS. 4A to 4C, the coil 10a in FIG. 4A in which the inter-turn resin 12 is selectively disposed in the corner B is the corner as described above. This is particularly preferable in that the abrasion of the insulating coating that easily occurs in B can be effectively prevented.

  As described above, in the reactor according to the present embodiment, the inter-turn resin layer 12 is formed in the region including the portion arranged between the coil turns on the surface of the strand 11 forming the coil 10 (10a to 10c). In addition, since the remaining portions are exposed, it is possible to suppress dielectric breakdown between coil turns when the coil 10 receives vibration, and to cool (heat radiation) the coil 10 with high efficiency. it can. In the conventional general reactor 90, the casting resin 95 is filled inside the case for accommodating the coil 91, and the insulation between the coil turns is ensured by the casting resin 95 that has entered the gap between the coil turns. Further, the coil 91 has been cooled by allowing heat to escape to the bottom plate 94 of the case provided with a cooling mechanism as appropriate through the casting resin 95. However, in the reactor according to the present embodiment, insulation between coil turns and cooling of the coil 10 can be performed without using a casting resin due to the above configuration. And by not using casting resin, it is not necessary to use the case provided with a side wall part. Thereby, compared with the past, the whole reactor can be simplified and reduced in weight.

[Reactor manufacturing method]
Next, the manufacturing method of the reactor concerning one Embodiment of this invention is demonstrated. This manufacturing method is characterized by the process of manufacturing the coil 10 described above. FIG. 5 schematically shows a method for manufacturing the coil 10. The manufacturing method shown in FIG. 5 is to manufacture the coil 10 shown in FIG. 3 in which the inter-turn resin layer 12 is continuously formed along the axial direction of the strand 11. Moreover, the case where the resin layer 12 between turns consists of photocurable resin is assumed.

  In the manufacturing process of the coil 10, the uncured curable resin 12 ′ is applied to the strand 11 in the coating portion 51, the curable resin 12 ′ is cured in the cured portion 52, and the strand in the winding portion 53. No. 11 winding is continuously performed in this order.

  The application unit 51 includes, for example, a dispenser nozzle 51a, and applies a curable resin 12 'that is uncured and has a high fluidity to a predetermined portion of the elongated wire 11. That is, when the coil 10 in which the inter-turn resin layer 12 is continuously formed as shown in FIG. 3 is manufactured, the curable resin 12 is formed on one side (or both sides) of the flat wire 11 as shown in FIG. Apply 'continuously.

  The curing part 52 forms the inter-turn resin layer 12 on the strand 11 by curing the curable resin 12 ′ applied in the application part 51 according to the curing method of the curable resin 12 ′ used. It is. In the case where a photocurable resin is used as the curable resin 12 ′, the cured portion 52 includes a (ultraviolet) light source 52 a such as a lamp or a laser, and a portion where the curable resin 12 ′ is applied by the application portion 51. Irradiation of the light L to the surface of the strand 11 containing

  In the winding part 53, the long strand 11 coated with the curable resin 12 'and hardened as described above is wound and formed as a coil. A known automatic winding machine or the like can be used for the winding unit 53. At this time, the winding is performed so that the portion where the inter-turn resin layer 12 is formed on the strand 11 is inside the central axis C of the coil 10. Thereby, in the completed coil 10, the resin layer 12 between turns is arrange | positioned in the site | part which an adjacent coil turn opposes, and will be in the state arrange | positioned in the inner part near the central axis C of the coil 10. FIG.

  In the present manufacturing method, the inter-turn resin layer 12 is formed on a part of the strand 11 by winding the strand 11 after applying and curing the curable resin 12 ′ to the strand 11. Thus, the coil 10 with other portions exposed can be easily manufactured. In addition, as a method in which a similar coil 10 can be manufactured, after winding the wire 11 into a coil shape, an uncured curable resin 12 ′ is applied or poured into a desired portion and then cured. A method is conceivable. However, in the case of this method, due to the fluidity of the uncured curable resin 12 ′, the applied curable resin 12 ′ is less likely to stay at a desired location of the coil 10, and the formation of the inter-turn resin layer 12 is desired. There is a possibility that the exposed part may not be left because it spreads to the part that does not exist. That is, the part covered with the inter-turn resin layer 12 and the part where the element wire 11 is exposed without being covered with the inter-turn resin layer 12 cannot be accurately made in the coil 10 as desired. End up. As a result, in the obtained coil 10, it becomes difficult to achieve both the effect of suppressing dielectric breakdown between coil turns and the effect of increasing the cooling efficiency of the coil 10. On the other hand, in this manufacturing method, the coating and curing of the curable resin 12 ′ are not performed after the coil 10 is three-dimensionally formed but at the stage of the long strand 11 having a simple planar shape. Therefore, on the surface of the strand 11, the exposed portion that is not covered with the inter-turn resin layer 12 is reliably left, and the portion that is covered with the inter-turn resin layer 12 and the exposed portion are accurately made. be able to. As a result, in the manufactured coil 10, it is easy to dispose the inter-turn resin layer 12 at the designed site, and it is possible to achieve both the effect of suppressing the dielectric breakdown between the coil turns and the cooling efficiency at a high level. Further, the application and curing process of the curable resin 12 'and the apparatus required for it are simple.

  Furthermore, in this manufacturing method, the coating process, the curing process, and the winding process are continuously executed, so that the manufacturing process of the coil 10 is particularly simplified. That is, when the coil 10 is manufactured by winding the long strand 11, the application portion 51 and the curing portion 52 are provided upstream of the winding portion 53 to apply and cure the curable resin 12 ′. The coil 11 can be completed by using the wire 11 as it is for winding. Specifically, in an automatic winding machine that is generally used in the past, a coating unit 51 including a dispenser nozzle 51a and the like, and a light source 52a between a supply source of the strand 11 and a portion around which the strand 11 is wound. The hardening part 52 which consists of etc. should just be provided.

  As described above, the curable resin 12 ′ constituting the inter-turn resin layer 12 may take any curing method from the viewpoint of characteristics required for the manufactured coil 10. From this point of view, it is preferable to use a curable resin 12 ′ having photo-curability or thermosetting. This is because, in the case of a resin having these curing methods, the configuration of the curing part 52 can be simplified. When the curable resin 12 ′ has photo-curing properties, the light source 52a such as a lamp or a laser may be used as the curing portion 52 as described above. When the curable resin 12 ′ has thermosetting properties, As the curing unit 52, a heat source such as a heater or a warm air generator may be used. Among these, the case where the curable resin 12 ′ has photocurability is preferable. Many of the photo-curing resins are cured in a short time when irradiated with light. Compared to the case where a thermosetting resin is used, the photo-curing resin is applied at the application unit 51 and then cured at the curing unit 52. In the meantime, it is difficult for the curable resin 12 ′ to flow out to an unintended part. That is, in the coil 10, the part covered with the inter-turn resin layer 12 and the part exposed without being covered with the inter-turn resin layer 12 are formed with high accuracy, and the effect of suppressing the dielectric breakdown between the coil turns and the coil 10 are determined. It is easy to achieve both cooling efficiency. Further, in the manufacturing process, the distance between the coating part 51 and the curing part 52 can be shortened, and the wire 11 can be wound into a coil shape at a high speed, so that the coil 10 can be manufactured at a high speed and manufactured. The configuration of the apparatus can be simplified.

  Of the photocurable resins, it is particularly preferable to use a so-called reactive hot melt (photocurable hot melt) having both photocurability and thermoplasticity as the curable resin 12 ′. In this case, the resin layer 12 between turns can be formed by applying a reactive hot melt that has been heated and fluidized to a predetermined site in the application unit 51 and then irradiating with light in the curing unit 52. When the reactive hot melt is applied to the surface of the strand 11 in the application portion 51, it is cooled almost instantaneously and loses its fluidity, and does not flow out to the part other than the applied part. The position to be played is determined. Then, by receiving light irradiation in this state, the positioned reactive hot melt is cured, and finally the inter-turn resin layer 12 is formed. Thus, by using a reactive hot melt as the curable resin 12 ′, it is possible to further suppress the outflow after coating, and the portions covered with the inter-turn resin layer 12 are exposed without being covered. Sites can be created with higher accuracy.

  5 described above is to form the coil 10 shown in FIG. 3 in which the inter-turn resin layer 12 is continuously formed in the axial direction of the strands 11. When the coils 10a to 10c in which the inter-turn resin layer 12 as shown in FIGS. 4A to 4C is formed discontinuously in the axial direction of the element wire 11 are manufactured, the coating portion 51 is cured. What is necessary is just to apply | coat discontinuous resin 12 'discontinuously instead of apply | coating continuously. At this time, when the coils 10a to 10c are formed in the next winding step, the curable resin 12 'is applied so that the part where the curable resin 12' is applied becomes a desired part in the coils 10a to 10c. It is necessary to control the site to do. For example, as shown in FIG. 4A, when forming the coil 10a in which the inter-turn resin layer 12 is disposed at the corner B, the curable resin is placed at the position where the coil 10a becomes the corner B after being wound. It is necessary to apply 12 'before winding.

  As described above, the coils 10a to 10c shown in FIGS. 4A to 4C in which the inter-turn resin layer 12 is discontinuously formed along the axial direction of the element wire 11 can easily increase the cooling efficiency. The coil 10a to 10c as designed cannot be obtained unless the positional relationship between the portion where the curable resin 12 ′ is applied and the winding structure of the coils 10a to 10c are matched. On the other hand, the coil 10 in which the inter-turn resin layer 12 is continuously formed along the axial direction of the strands 11 as shown in FIG. It is not necessary to pay particular attention to the positional relationship between the application site and the winding structure of the coil 10, and it is excellent in manufacturing simplicity.

  Examples of the present invention and comparative examples are shown below. In addition, this invention is not limited by these Examples.

<Preparation of test sample>
[Example 1]
As shown in FIG. 5, a coil was manufactured by using a device in which an ultraviolet curable acrylic resin dispenser nozzle and an ultraviolet light source were arranged upstream of an automatic winding machine, and using a rectangular wire having an enamel coating as a strand. . The application of the ultraviolet curable acrylic resin was performed on the surface of one side of the strand, and the coating was performed so as to occupy the entire area continuously in the axial direction so as to occupy a part in the width direction of the strand. Immediately after application, the portion where the ultraviolet curable resin is applied is irradiated with ultraviolet rays, and then the strand is wound so that the portion where the ultraviolet curable resin is applied is inside the central axis C. A coil was formed. Then, an assembly of a coil and a core having the shape shown in FIG. 1 was formed, fixed to the bottom plate, further connected to a terminal, and assembled as a reactor.

[Example 2]
A similar reactor was prepared by changing the ultraviolet curable acrylic resin of Example 1 to an ultraviolet curable hot melt resin, and the reactor according to Example 2 was obtained.

[Example 3]
The ultraviolet curable acrylic resin of Example 1 was changed to a thermosetting epoxy resin and cured by heating to produce a similar reactor, and a reactor according to Example 3 was obtained. However, in consideration of the time required for curing the thermosetting resin, the winding speed of the coil was slower than those in Examples 1 and 2.

[Examples 4 to 6]
Instead of continuously applying the resin to the entire region in the axial direction of the strand, the resin is applied discontinuously, and the coil is formed so that the applied portions are arranged at the four corners of the coil. The reactor similar to 3 was manufactured and it was set as the reactor concerning Examples 4-6, respectively.

[Comparative Example 1]
A reactor similar to Example 1 was produced without applying a curable resin (without forming a resin layer between coil turns), and the reactor according to Comparative Example 1 was obtained.

[Comparative Examples 2 and 3]
A reactor similar to Example 1 (continuous application) and Example 4 (discontinuous application) is formed using a thermoplastic resin (polyolefin non-crosslinked hot melt resin) instead of the ultraviolet curable acrylic resin, Reactors according to Comparative Example 2 and Comparative Example 3 were used, respectively. The thermoplastic resin was solidified by applying it to the strand in a plasticized state by heating and allowing to cool.

[Comparative Example 4]
The reactor according to Comparative Example 4 was prepared using the same ultraviolet curable hot melt as in Example 2. However, unlike Example 2, the UV curable hot melt is not applied to the coil wire before winding, but instead spreads over the entire surface of the wire constituting the coil after coil formation. Applied.

[Comparative Example 5]
A reactor having the same shape as in Example 1 was produced using a welding winding (winding in which a welding layer made of a resin that can be melted by heat was formed on the outer layer of the insulating coating) as a coil wire. And in the state which heated the coil and welded between coil turns, it integrated in the reactor and set it as the reactor concerning the comparative example 5. Resin is not applied to the outside of the welded winding.

<Test method>
[Evaluation of coating condition]
Each reactor was subjected to a vibration test in accordance with an automobile part vibration test method defined in JIS D1601. Then, after the vibration test, visually check whether there is any abnormality in the coating state, such as peeling, on the insulation coating layer (enamel coating layer) on the surface of the wire arranged in the region between the coil turns. went. Those in which no abnormalities such as peeling were found in the insulating coating layer were evaluated as acceptable “◯”, and those in which abnormalities such as peeling were observed were determined as “failed”.

[Reactor characterization]
Before and after the vibration test, the electrical characteristics of the reactor were evaluated, and it was confirmed whether or not the characteristics were deteriorated by the vibration test. Those in which the characteristics were not deteriorated were regarded as acceptable “◯”, and those in which the characteristics were decreased were regarded as unacceptable “x”.

<Test results>
Table 1 shows the results of the evaluation of the covering state after the vibration test and the characteristics evaluation of the reactor for the reactors according to the examples and the comparative examples.

  As summarized in Table 1, in the reactors according to Examples 1 to 6 in which the curable resin was continuously applied, cured, and wound, and the curable resin was disposed on a part of the surface of the strand. The vibration test was conducted both when the curable resin was continuously disposed on the inner portion of the coil (Examples 1 to 3) and when it was discontinuously disposed (Examples 4 to 6). Later, there was no abnormality such as wear in the insulation coating layer of the strands, and the characteristics did not deteriorate from the initial state.

  On the other hand, in the reactor of Comparative Example 1 in which the inter-turn resin layer was not formed, peeling occurred in the insulating coating layer due to friction between the coil turns in the vibration test. Correspondingly, the reactor characteristics deteriorated due to dielectric breakdown between coil turns.

  In the reactors according to Comparative Examples 2 and 3 using a thermoplastic resin instead of the curable resin, no abnormality such as wear was observed in the insulating coating layer even after the vibration test. However, when the characteristic test was conducted by energizing the coil, the thermoplastic resin disposed between the coil turns was melted during the test due to the heat generated from the coil.

  In the reactor according to Comparative Example 4 which is not applied to a part of the surface in the state of a wire, but applied to the entire surface after the coil is formed, the insulation coating layer has an abnormality such as wear when subjected to a vibration test. Was not seen. However, in the characteristic evaluation, it was observed that the characteristic was deteriorated as compared with the initial state through the vibration test. This is considered to be due to insufficient cooling of the coil being energized.

  In the case where the welded winding according to Comparative Example 5 was used, it was confirmed that an abnormal coating state occurred in the insulating coating layer when the vibration test was performed. Furthermore, in the characteristic evaluation after the vibration test, the characteristic was deteriorated due to dielectric breakdown between the coil turns. This is presumably because the adhesion between the insulating coating layer and the conductor wire was lowered by the vibration test, and the dielectric breakdown was caused by the energization during the characteristic evaluation. That is, the weld layer cannot sufficiently prevent the insulation coating layer from being worn by the vibration of the coil.

<Consideration of results>
As in Examples 1 to 6 and Comparative Example 4, by disposing the thermosetting resin between the coil turns of the reactor, even when the reactor is vibrated, the insulation coating layer is brought about by contact between the coil turns. Is prevented from being damaged such as peeling. Also, unlike the case where a thermoplastic resin is used (Comparative Examples 2 and 3), even if the coil generates heat by energizing the coil, the curable resin disposed between the coil turns does not melt, and the coil turn It is easy to maintain the function of the curable resin that suppresses the dielectric breakdown.

  However, when the curable resin is applied to the entire coil as in Comparative Example 4, the coil is sufficiently cooled by covering the entire surface of the wire constituting the coil with the curable resin. Can not. On the other hand, when the thermoplastic resin is arranged only on a part of the surface of the strand as in Examples 1 to 6, the coil is cooled via the surface of the strand not covered with the curable resin. Is done. Due to the effect of this cooling and the effect of maintaining insulation, the same characteristics as the original are exhibited after the vibration test. That is, the protection of the insulating coating layer and the maintenance of the cooling performance are compatible. In this respect, the same result is obtained when the curable resin is continuously arranged on the strands as in Examples 1 to 3 and when it is discontinuously arranged as in Examples 3 and 4. Yes. This is because the curable resin is applied and cured in the state of a wire, even when disposing the curable resin continuously or discontinuously, the part covered with the curable resin It is interpreted that this is because the unexposed part and the exposed part are separately formed on the wire.

  In Examples 3 and 6 using the thermosetting resin, as in Examples 1, 2, 4 and 5 using the ultraviolet curable resin, in the vibration test, the insulation coating was peeled off. Prevention and maintenance of characteristics. However, in order to secure the time required for curing the thermosetting resin, the speed of winding the coil is made slower than in the case of the resin having ultraviolet curing properties. From this, it can be said that it is particularly preferable to use an ultraviolet curable resin as the curable resin applied to the strands.

  As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to the said embodiment and Example at all, and various modification | change is possible in the range which does not deviate from the summary of this invention. .

10 (10a to 10c) Coil 11 Wire 11a Conductor wire 11b Insulation coating layer 12 Inter-turn resin layer 12 ′ (uncured) curable resin 20 Magnetic core 51 Application portion 51a Dispenser nozzle 52 Curing portion 52a Light source 53 Winding portion

Claims (8)

Applying a curable resin in an uncured state to a part of the surface of the wire whose surface is covered with an insulating coating layer;
Curing the applied curable resin; and
The step of winding the element wire to form a coil is performed continuously in this order while the portion where the curable resin is disposed is disposed at a portion where adjacent coil turns are opposed to each other. A method for manufacturing a reactor.   The method for manufacturing a reactor according to claim 1, wherein the coil is a rectangular coil, and the curable resin is disposed at least at a corner portion of the rectangular coil.   The curable resin is disposed in a region relatively close to the central axis of the coil, and the portion where the element wire is exposed without being covered with the curable resin is located in the coil rather than the region in which the curable resin is disposed. It arrange | positions in the area | region far from the center axis | shaft of this invention, The manufacturing method of the reactor of Claim 1 or 2 characterized by the above-mentioned.   The method for producing a reactor according to any one of claims 1 to 3, wherein the curable resin is discontinuously arranged along an axial direction of the strand.   The method for manufacturing a reactor according to any one of claims 1 to 3, wherein the curable resin is continuously arranged over the entire axial direction of the strands.   The method for producing a reactor according to any one of claims 1 to 5, wherein the curable resin has photocurability. The method for manufacturing a reactor according to any one of claims 1 to 6, wherein the curable resin is disposed only on one surface of the element wire. In a reactor having a coil formed by spirally winding an element wire whose surface is covered with an insulating coating layer,
In a portion where adjacent coil turns of the coil are opposed to each other, a layer of a curable resin in a cured state is formed on a part of the surface of one surface of the strand. In the direction, the curable resin layer is not formed,
The area | region which is not covered with the layer of the said curable resin of the surface of the said strand is exposed to the surrounding environment in which the said reactor is installed, The reactor characterized by the above-mentioned.

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