Reactor

Abstract

The present invention provides a reactor. The reactor (10) comprises: a coil (12); a core (16) which accommodates the coil (12) and is configured to be split; and a resin molded portion (18) which covers and fixes at least one side of the core (16). The resin molded portion (18) comprises an opening portion (68) which exposes a portion of the outer peripheral surface (54a) of a cover core portion (54) in the core (16) to the outside. The opening portion (68) is opened in a manner that faces only the cover core portion (54) of the split core (16), and the boundary portion (62) between the cover core portion (54) and the base core portion (52) is covered by the molded body (64) of the resin molded portion (18).

Description

Technical Field

[0001] The present invention relates to a reactor which is molded in a state where a coil is accommodated inside a core. Background Art

[0002] In the past, a reactor is known, which includes: a coil wound with a rectangular cross-section of a flat wire; and a set of cores that accommodate the coil. As disclosed in Japanese Patent Publication No. 2017-107995, the reactor includes: a coil; a magnetic core that is arranged on the inner circumference of the coil; and an outer casing that covers the outer sides of the coil and the core.

[0003] In the case of manufacturing the above reactor, after the coil is placed between a group of split parts constituting the core to form a coil assembly, the upper and lower molds are fitted together in a manner to cover the coil assembly, and the core is pressed in the axial direction to be positioned by inserting a retaining pin through the through hole of the split part. Then, molten resin material is injected into the upper and lower molds and solidified to obtain a reactor in which the coil assembly is covered by an outer casing composed of a resin material.

[0004] However, when manufacturing the above-mentioned inductor, since a group of split components constituting the core are fixed only in the axial direction by retaining pins, when the side surfaces of the split components are pressed by the resin material injected into the mold, the split components will move in a horizontal direction perpendicular to the axial direction, and one split component and another split component will be offset in the horizontal direction.

[0005] Therefore, in order to suppress the positional deviation of the split components during the manufacturing process of the above-mentioned reactor, for example, it is conceivable to arrange the retaining pin inserted in the axial direction on the side surface of the split component so as to straddle the boundary between the split component arranged above and the split component arranged below and abut against the side surface. However, when there is a manufacturing deviation of the split component and a gap is formed between the front end of the retaining pin and the side surface of the split component, the molten resin material enters the gap and solidifies, thereby causing burrs on a part of the outer packaging. Summary of the invention

[0006] A general object of the present invention is to provide a reactor capable of suppressing the generation of burrs in a resin molded portion.

[0007] The present invention is a reactor having: a coil; a core that accommodates the coil and is configured to be divisible; and a resin molded portion that covers at least a side surface of the core and fixes the core, wherein:

[0008] The resin molded portion has an exposed portion that exposes a portion of the core to the outside. The exposed portion is provided to face only one of the one core portion and the other core portion that divide the core. The boundary between the one core portion and the other core portion is covered by the resin molded portion.

[0009] According to the present invention, the core containing the coil is arranged to be split freely, and has a resin molded portion that covers at least the side surface of the core and fixes it, and the resin molded portion has an exposed portion that exposes a part of the core to the outside. Moreover, the exposed portion only faces any one of the split core portion and the other core portion, and the boundary portion between the one core portion and the other core portion is covered by the resin molded portion.

[0010] Therefore, even if a manufacturing deviation occurs in one or the other core part after the core is divided and a step is generated on the side of the core part, when the resin molded part is molded from the molten resin material, the mold part that is pressed against the side surface only abuts against any one of the core parts, so that no gap is generated between the mold part and the core part.

[0011] As a result, by providing the resin molded portion on the core so as to straddle the boundary between one core portion and the other core portion, it is possible to appropriately suppress the resin material from entering the gap generated between the side surface of the core portion and the mold member to form burrs.

[0012] The above-mentioned objects, features and advantages can be easily understood through the following description of the embodiments described with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is an external perspective view of a reactor according to an embodiment of the present invention.

[0014] Figure 2 is Figure 1 A three-dimensional view of the appearance of a coil assembly consisting of a core, a coil, and a winding drum in a reactor.

[0015] Figure 3 yes Figure 2 An exploded perspective view of the coil assembly shown.

[0016] Figure 4 yes Figure 1 The overall plan view of the reactor is shown.

[0017] Figure 5A It is along Figure 4 The cross-sectional view of the VA-VA line, Figure 5B It is shown in Figure 5A A cross-sectional view showing a case where radial manufacturing deviation occurs on the outer peripheral surface of a base core.

[0018] Fig. 6Ais a partially omitted cross-sectional view showing a reactor of a modified example, Figure 6B It is shown in the composition Fig. 6A A partially omitted cross-sectional view showing a case where manufacturing variations occur in the first divided core portion of the reactor. DETAILED DESCRIPTION

[0019] like Figure 1 to Figure 4 As shown, the reactor 10 includes: a coil 12, both ends of which are led out from the outer peripheral side and wound by an α winding method; a drum 14, which is arranged to surround the coil 12; a core 16, which accommodates the coil 12 and the drum 14; and a resin molded portion 18, which covers the outer side of the core 16. And the reactor 10 is placed and used in a manner such that, for example, the cover core portion (core portion) 54 of the core 16 is located at the top (arrow A1 direction) and the base core portion (core portion) 52 is located at the bottom (arrow A2 direction).

[0020] The coil 12 is made of, for example, a conductive flat wire covered with an insulating film such as enamel, and is wound on the outer periphery of the drum 14 in two layers in the vertical direction by α-winding with its wide surface facing the radial direction.

[0021] In detail, Figure 3 As shown, the coil 12 is formed with an upper layer 20 and a lower layer 22 which are respectively wound multiple times, and a first end 24 as an end of the upper layer 20 and a second end 26 as an end of the lower layer 22 are led outward. A portion connecting the upper layer 20 and the lower layer 22 is provided in the middle of the coil 12. Moreover, the upper layer 20 and the lower layer 22 in the coil 12 are formed by the same number of turns, and their outermost diameters are formed to be substantially the same.

[0022] The first end 24 of the coil 12 as one end along the winding direction is led outward in the radial direction from the outermost peripheral portion of the winding portion of the upper layer 20 of the two layers, and the second end 26 as the other end is led outward in the radial direction from the outermost peripheral portion of the winding portion of the lower layer 22 of the two layers, and the first end 24 and the second end 26 are arranged to be substantially parallel (see Figure 4 ).

[0023] The reel 14 is formed of a resin material, and includes a first holder 28 that covers the upper and lower sides of the coil 12 , and a second holder 30 that covers the outer peripheral side of the coil 12 and is connected to the first holder 28 .

[0024] The first retaining member 28 comprises: a cylindrical portion 32 having a circular cross-section and extending in the axial direction (in the direction of arrows A1 and A2); a plurality of first bridge portions 34 formed at the upper end of the cylindrical portion 32 and extending radially outward; an annular first circular ring portion 36 connecting the outer edge portions of the first bridge portions 34 to each other; a plurality of second bridge portions 38 formed at the lower end of the cylindrical portion 32 and extending radially outward; and an annular second circular ring portion 40 connecting the outer edge portions of the second bridge portions 38 to each other.

[0025] The cylindrical portion 32 is formed with the same diameter, the coil 12 is wound around the outer circumference thereof, and the first and second bridge portions 34, 38 are formed to be spaced equally from each other along the circumferential direction of the cylindrical portion 32. Moreover, the first and second bridge portions 34, 38, and the first and second annular portions 36, 40 are spaced apart and formed in parallel with a predetermined interval in the axial direction (arrow A1, A2 direction) of the cylindrical portion 32. In other words, the first retainer 28 is formed to protrude from the upper end and the lower end of the cylindrical portion 32 to the radially outer side in a flange shape.

[0026] The first annular portion 36 is provided with a plurality of engagement holes 42 spaced apart from each other along its circumferential direction. The engagement holes 42 are formed radially outside the first bridging portion 34 and penetrate the axial direction (in the directions of arrows A1 and A2 ) of the spool 14 .

[0027] Furthermore, a cover portion 44 protruding radially outward is formed on the first annular portion 36 between two adjacent first bridge portions 34. The cover portion 44 is formed, for example, to have a substantially rectangular cross section, protrudes radially outward by a predetermined length relative to the outer circumference of the first annular portion 36, and is smoothly connected to the outer circumference.

[0028] The second holder 30 has an outer peripheral wall 46 formed in an annular shape, and a guide portion 48 protruding radially outward relative to the outer peripheral wall 46. The cross section of the outer peripheral wall 46 is formed in a circular shape with a diameter substantially the same as that of the first annular portion 36 of the first holder 28, and extends at a predetermined height along the up-down direction (the direction of arrows A1 and A2). In addition, a plurality of claws 50 are formed at the upper end of the outer peripheral wall 46, and further protrude upward (the direction of arrows A1). The claws 50 are formed in a triangular cross section so as to gradually protrude radially outward as they go downward from the upper end, and are provided at equal intervals from each other along the circumferential direction of the outer peripheral wall 46.

[0029] Furthermore, in a state where the coil 12 is wound around the cylindrical portion 32 of the first holder 28, the upper end of the outer peripheral wall 46 of the second holder 30 is brought into contact with the first annular portion 36, and the plurality of claws 50 are respectively inserted into the engaging holes 42 of the first annular portion 36. Thus, the first holder 28 and the second holder 30 sandwich the coil 12 therebetween, and are connected in the axial direction (in the direction of arrows A1 and A2) while being positioned relative to each other in the circumferential direction.

[0030] Furthermore, the guide portion 48 of the second holder 30 is formed so that the cross section opening toward the first holder 28 side (arrow A1 direction) is U-shaped, and the upper portion of the guide portion 48 is covered by the cover portion 44 of the first holder 28, thereby forming a space with a rectangular cross section opening toward the radial outside. Furthermore, the first and second ends 24, 26 of the coil 12 wound on the cylindrical portion 32 of the first holder 28 are taken out to the outside (radially outside) through the inside of the guide portion 48 and the cover portion 44.

[0031] like Figure 1 to Figure 3 As shown, the core 16 is formed of, for example, a magnetic material into a cylindrical shape that can be divided in the upper and lower directions (directions of arrows A1 and A2), and includes: a base core portion 52, which is arranged at the lower portion; a cover core portion 54, which is arranged to cover the upper portion of the base core portion 52; and a cylindrical core shaft portion 56, which is formed at the center of the base core portion 52, and has a storage space 58 on the outer peripheral side of the core shaft portion 56 for inserting and storing the reel 14 wound with the coil 12.

[0032] In addition, a lead-out groove 60 extending from the storage space 58 toward the outside is formed on the base core portion 52 and the cover core portion 54 constituting the core 16, and the guide portion 48 and the cover portion 44 of the reel 14 pass through the lead-out groove 60, and the first and second ends 24 and 26 of the coil 12 are respectively led out to the outside through the guide portion 48.

[0033] In addition, in a state where the winding drum 14 on which the coil 12 is wound is inserted through the core shaft portion 56 of the base core portion 52, the upper portion of the base core portion 52 is covered with the cover core portion 54 to form a Figure 2 The coil assembly S shown in the figure, the upper end of the base core 52 and the lower end surface of the cover core 54 contact and connect to form a boundary 62. The boundary 62 extends in a direction (arrow B direction) substantially perpendicular to the up-down direction (arrow A1, A2 direction).

[0034] The resin molded portion 18 is made of, for example, a resin material and is formed by injection molding to cover the outside of the coil assembly S. It includes: a molded body 64 that covers the outer peripheral side of the core 16; and a mounting portion 66 that protrudes radially outward from the lower end outer peripheral surface of the molded body 64.

[0035] The molded body 64 is formed in a cylindrical shape so as to have a certain thickness on the radially outer side relative to the outer peripheral surface (side surface) of the core 16, and is formed so that the guide portion 48 and the cover portion 44 of the reel 14 are exposed to the outside, and the upper end of the molded body 64 extends radially inward so as to cover a part of the upper end of the cover core portion 54. In other words, the molded body 64 is formed so as to face the outer peripheral surface of the core 16.

[0036] Furthermore, a plurality of openings (exposed portions) 68 are formed in the mold body 64 and penetrate in the radial direction. The openings 68 are formed, for example, in a long rectangular cross-sectional shape along the circumferential direction of the mold body 64 and open at a position above (in the direction of arrow A1) the boundary portion 62 of the core 16. That is, the openings 68 open to face a portion of the outer peripheral surface 54a of the cover core portion 54 located above the boundary portion 62, and the outer peripheral surface 54a is exposed to the outside through the openings 68.

[0037] In other words, the base core 52 below the boundary 62 is not exposed to the outside due to the opening 68. Figure 4 As shown in FIG. 1 , a case where the mold body 64 has three openings 68 spaced apart from each other in the circumferential direction will be described.

[0038] The mounting portion 66 is formed in a flange shape, for example, and is provided at four locations at equal intervals in the circumferential direction of the mold body 64. A bolt hole 70 for inserting a fixing bolt (not shown) is formed in the center of the mounting portion 66. In addition, when the mounting portion 66 is in contact with a mounting surface (not shown) for fixing the reactor 10, the fixing bolt (not shown) is inserted through the bolt hole 70 and screwed into the mounting surface, thereby fixing the reactor 10 including the mounting portion 66 at a predetermined position.

[0039] The reactor 10 according to the embodiment of the present invention is basically configured as described above. Next, a description will be given of a case where the coil assembly S constituting the reactor 10 is molded to form the resin mold portion 18 .

[0040] First, if Figure 5A As shown, the coil assembly S constituting the reactor 10 is housed between the lower mold 72 and the upper mold 74 , and the base core portion 52 constituting the core 16 abuts against the bottom wall of the lower mold 72 , and the cover core portion 54 abuts against the inner wall of the upper mold 74 .

[0041] Then, the three movable molds 76 are brought close to the cover core 54 from the radially outer side (in the direction of arrow C), and abut against the outer peripheral surface 54a on the cover core 54 side (in the direction of arrow A1) at a position higher than the boundary 62 between the base core 52 and the cover core 54 by a predetermined height. In other words, the movable mold 76 does not abut against the outer peripheral surface 52a of the base core 52, but abuts against a position away from the boundary 62 between the two in the upward direction (in the direction of arrow A1).

[0042] Thus, the coil assembly S is covered by the upper mold 74 , the lower mold 72 , and the movable mold 76 , and the space between the coil assembly S and the upper mold 74 and the lower mold 72 , and the space between the movable mold 76 and the coil assembly S become cavities to which the resin material is supplied.

[0043] Then, the molten resin material is filled into the interior of the upper mold 74 and the lower mold 72 through a supply port not shown in the figure, whereby the outer peripheral side of the coil assembly S is covered with the resin material introduced into the cavity, and the coil 12 and the reel 14 are covered with the resin material flowing into the storage space 58 of the core 16 through the lead-out groove 60. In detail, the outer peripheral sides of the base core portion 52 and the cover core portion 54 constituting the core 16 are covered with the resin material except for the portions abutting against the three movable molds 76 and the portions facing the lead-out groove 60, and the upper portion of the cover core portion 54 is only covered in an annular shape near the outer edge to form the molded body 64.

[0044] Finally, after a portion of the outer side of the coil assembly S and the storage space 58 of the core 16 are filled with the resin material, the resin material is hardened by cooling for a predetermined time, thereby forming the resin molded portion 18 in which the coil assembly S is covered with the resin material. As a result, the following reactor 10 is constructed: the coil 12 and the winding drum 14 are fixed at predetermined positions in the storage space 58 of the core 16, and Figure 1 and Figure 4 As shown, a plurality of openings 68 are formed so as to face the outer peripheral surface 54 a of the cover core portion 54 , and a portion of the outer peripheral surface 54 a is exposed to the outside.

[0045] And, if Figure 1 and Figure 5A As shown, a boundary portion 62 between the base core portion 52 and the cover core portion 54 constituting the core 16 is covered by a mold body 64 covering the outer peripheral side of the core 16 , and the boundary portion 62 is not exposed to the outside.

[0046] In addition, in the above-mentioned reactor 10, the structure in which the opening portion 68 is provided at a position facing the cover core portion 54 constituting the core 16 is adopted, but the present invention is not limited to this, and a structure in which the opening portion 68 is provided on the side of the base core portion 52 below the boundary portion 62 may be adopted. That is, the structure in which the opening portion 68 is provided only in one of the base core portion 52 and the cover core portion 54 constituting the core 16 and the boundary portion 62 therebetween is covered by the mold body 64 may be adopted.

[0047] Then, if Figure 5B As shown, in the manufacturing process of the reactor 10, a manufacturing variation occurs in the base core portion 52 constituting the core 16, and the outer peripheral surface 52a of the base core portion 52 is offset radially inward by a predetermined distance L relative to the outer peripheral surface 54a of the cover core portion 54.

[0048] First, with the coil assembly S housed in the upper mold 74 and the lower mold 72, the movable mold 76 is brought into contact with the outer peripheral surface 54a of the cover core portion 54. Then, the cavities inside the upper mold 74 and the lower mold 72 are filled with molten resin material, and the resin material is filled on the outer peripheral side of the core 16 in a manner that covers the step 78 generated between the cover core portion 54 and the base core portion 52.

[0049] Then, after the outer peripheral side of the coil assembly S and the storage space 58 of the core 16 are filled with the resin material, the resin material is hardened by cooling for a predetermined time to form the resin molded portion 18. As a result, the reactor 10 is configured as follows: the coil 12 and the winding drum 14 are fixed at predetermined positions relative to the core 16, and a plurality of openings 68 are formed so as to face the outer peripheral surface 54a of the cover core portion 54, and the outer peripheral surface 54a of the cover core portion 54 is exposed to the outside.

[0050] Furthermore, the boundary portion 62 between the base core portion 52 and the cover core portion 54 constituting the core 16 is covered by the mold body 64 covering the outer peripheral side of the core 16, and the boundary portion 62 is not exposed to the outside. Therefore, the step 78 formed below the boundary portion 62 and facing the radial direction is properly covered by the mold body 64, and a gap is not generated between the outer peripheral surface 52a of the base core portion 52 having a dimensional deviation toward the radial inside and the movable mold 76, which can prevent the resin material from entering the gap and forming burrs during injection molding.

[0051] As described above, in the present embodiment, the resin molded portion 18 constituting the reactor 10 is formed to cover the outside of the core 16 which is freely divisible in the axial direction (in the direction of arrows A1 and A2), and is formed so that when the resin molded portion 18 is molded by covering the coil assembly S which accommodates the coil 12 and the reel 14 in the storage space 58 of the core 16 with a resin material, the opening portion 68 opened on the outer peripheral surface of the resin molded portion 18 is located above (in the direction of arrow A1) relative to the boundary portion 62 between the base core portion 52 and the cover core portion 54 constituting the core 16.

[0052] Therefore, even if a manufacturing deviation in the radial direction occurs on the base core portion 52 or the cover core portion 54 constituting the core 16, thereby forming a radial step 78 between the outer peripheral surface 52a of the base core portion 52 and the outer peripheral surface 54a of the cover core portion 54, during injection molding, the movable mold 76 will not contact both the outer peripheral surfaces 52a and 54a, but will only contact the outer peripheral surface 54a of the cover core portion 54 to form an opening portion 68, so that no gap will be generated between the outer peripheral surface 52a of the base core portion 52 which is recessed relative to the outer peripheral surface 54a of the cover core portion 54 and the front end of the movable mold 76.

[0053] As a result, even if radial manufacturing deviation occurs on the base core portion 52 and the cover core portion 54 constituting the core 16, the boundary portion 62 will not be exposed to the outside through the opening portion 68 of the resin molded portion 18, but will be properly covered by the molded body 64, thereby suppressing the generation of burrs on the resin molded portion 18 caused by the gap generated between the outer peripheral surfaces 52a, 54a of the core 16 and the movable mold 76.

[0054] Furthermore, the case where the core 16 constituting the reactor 10 is composed of the base core portion 52 and the cover core portion 54 which can be divided in the vertical direction (the arrow A1 and A2 directions) has been described, but the present invention is not limited to this. Fig. 6A and Figure 6B Like the core 102 of the reactor 100 shown in the figure, it may be composed of a first split core portion 104 and a second split core portion 106 having a semicircular cross section that can be divided into two in the horizontal direction (the direction of arrow B) perpendicular to the axial direction.

[0055] In from Fig. 6AWhen the core 102 is viewed in the axial direction, the reactor 100 includes a core 102 having a circular cross section, wherein the first and second split core portions 104 and 106 having semicircular cross sections can abut against each other via a boundary portion 108 and can be freely split in a radial direction substantially perpendicular to the axial direction. The outer peripheral side of the core 102 is covered by a mold body 112 constituting a resin mold portion 110, and an opening portion 114 is opened at a position facing the outer peripheral surface of the first split core portion 104. The opening portion 114 is opened in a radially penetrating manner at a position not facing the boundary portion 108 between the first split core portion 104 and the second split core portion 106.

[0056] Then, the outer peripheral side of the core 102 is covered by a mold (not shown) and the movable mold 76 is in contact with the outer peripheral surface of the first split core portion 104, and the molten resin material is filled into the mold covering the outer peripheral side of the core 102. Thus, the mold body 112 constituting the resin molded portion 110 is formed in a manner covering the outer peripheral side of the core 102, and the opening 114 formed by opening a part of the mold body 112 is formed to face the outer peripheral surface of the first split core portion 104, thereby the outer side of the core 102 is molded by the resin molded portion 110.

[0057] Then, if Figure 6B As shown, for example, when the first split core portion 104 is slightly offset relative to the second split core portion 106 with the boundary portion 108 as the boundary due to manufacturing deviation of the core 102, the outer peripheral sides of the first and second split core portions 104 and 106 are covered with a resin material filled in a mold not shown, and a step 116 generated between the boundary portion side end 104a of the first split core portion 104 and the boundary portion side end 106a of the second split core portion 106 is covered by the resin material.

[0058] As a result, the step 116 formed at the boundary portion 108 between the first split core portion 104 and the second split core portion 106 is properly covered by the molding body 112 of the resin molding portion 110, and no gap is generated between the outer peripheral surface of the second split core portion 106 and the movable mold 76. Therefore, in the resin molding portion 110, the generation of burrs caused by the resin material entering the gap can be properly suppressed.

[0059] The reactor of the present invention is not limited to the above-described embodiment, and it is of course possible to adopt various structures without departing from the gist of the present invention.

Claims

1. A reactor, comprising: Coil; a core that accommodates the coil and is configured to be divisible; and a resin molded portion that covers at least one side surface of the core and fixes the core, in, The resin molded portion includes a cylindrical mold body covering the outer periphery of the core, and an exposed portion formed in the mold body and penetrating the mold body in a radial direction to expose a portion of the core to the outside. The core includes a first core portion and a second core portion divided in the axial direction of the core. The exposed portion is arranged to face the outer peripheral surface of the first core portion, the boundary portion between the first core portion and the second core portion in the axial direction of the core is covered by the molding body of the resin molding portion, and the exposed portion is configured in a manner deviated from the boundary portion in the axial direction.

2. A reactor, comprising: Coil; a core that accommodates the coil and is configured to be divisible; and a resin molded portion that covers at least one side surface of the core and fixes the core, in, The resin molded portion includes a cylindrical mold body covering the outer periphery of the core, and an exposed portion formed in the mold body and penetrating the mold body in a radial direction to expose a portion of the core to the outside. The core includes a first core portion and a second core portion divided in a radial direction substantially perpendicular to an axial direction of the coil. The exposed portion is arranged to face the outer peripheral surface of the first core portion, the boundary portion between the first core portion and the second core portion in the circumferential direction of the core is covered by the molding body of the resin mold portion, and the exposed portion is configured in a manner deviated from the boundary portion in the circumferential direction.

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