JP2020064979A - coil - Google Patents

Abstract

To realize a one-turn through shape by inserting a busbar into a core and fixing the bus bar with a strip-shaped member to provide a coil with a structure that is easy to be manufactured at low cost.SOLUTION: A coil 1 according to the present invention includes a core 2 having two through holes 24, a U-shaped bus bar 3 having plate-shaped portions 31 facing each other, a bobbin 4 that insulates the core 2 from the bus bar 3, and a tape 5 that fixes the bus bar 3 in which the plate-shaped portion 31 is inserted into the through hole 24 to the core 2 with the bobbin 4. Further, the bus bar 3 is composed of a U-shaped member formed by flatwise-bending a metal plate.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an on-vehicle coil applied to a noise filter.

  Various types of coils for vehicles are known. For example, as a coil for a noise filter that removes radio noise and the like, there has been proposed a coil in which a linear bus bar covered with an insulation is wound around a core with two turns of alpha winding. In the coil composed of the core and the bus bar, a structure for fixing the core and the bus bar is indispensable. As a fixing structure of the core and the bus bar, there is, for example, a structure in which the bus bar side or the core side has a retaining shape.

JP, 2005-236026, A

  The following problems have been pointed out for conventional coils. That is, a coil having a retaining shape for fixing the bus bar and the core tends to have a complicated structure and tends to increase in size. In addition, in the coil having the retaining shape, an external force may be applied to the retaining shape portion, which may damage the insulating material which is a flexible material or the core. Further, in the coil for preventing the slip-out, the number of work steps is increased and the cost is increased.

  Therefore, it is conceivable to omit the retaining shape and fix the bus bar and the core with an adhesive such as thermosetting. However, the use of an adhesive takes a long time to cure the adhesive. In addition to that, a jig for fixing the bus bar and the core and a facility for curing the adhesive are required. As a result, even a coil using an adhesive for fixing the bus bar and the core has a problem of high cost.

  The present invention has been proposed in order to solve the above problems, and an object thereof is to insert a bus bar into a core and fix it with a belt-shaped member to realize a one-turn through shape, which is easy to manufacture at low cost. It is to provide a coil of structure.

In order to achieve the above object, the coil of the present invention comprises the following constituent elements (a) to (d).
(A) A core provided with two through holes.
(B) A U-shaped bus bar having long side portions facing each other and a connecting portion connecting the long side portions.
(C) A bobbin that insulates the core from the bus bar.
(D) A strip-shaped member for fixing the bus bar, in which the long side portion is inserted into the through hole of the core, to the core together with the bobbin.

  The bus bar may be composed of a U-shaped member formed by flatwise bending a metal plate. The core may have a flat portion in contact with the belt-shaped member. The bobbin may include a sleeve portion that can be inserted into the through hole of the core and can accommodate the plate-shaped portion of the bus bar.

  The bobbin may be made of a molding resin integrally molded with the bus bar. A portion of the bobbin that covers the connecting portion of the bus bar, and a surface of the bobbin that covers the connecting portion of the bus bar when the long side portion of the bus bar is inserted into a through hole of the core on a surface facing the core. You may make it provide the abutting surface which abuts on the said core. A portion of the bobbin that covers the connecting portion of the bus bar may have a projecting portion that projects toward the outside of the core. The projecting portion may project from the bobbin so that at least a portion around which the strip-shaped member is wound has the same outer shape as the core.

  The bobbin may form a hole through which the connecting portion of the bus bar is exposed. The bobbin may form a groove portion into which the strip-shaped member is fitted. The groove may have a curved surface at the end. The strip-shaped member may be an adhesive tape. A heat dissipation member may be provided so as to be in contact with the bus bar.

  According to the present invention, by inserting the bus bar into the core and fixing it with the strip-shaped member, a one-turn penetrating shape can be realized, and a coil having a structure that can be easily manufactured at low cost can be obtained.

The disassembled perspective view of 1st Embodiment. The perspective view of 1st Embodiment. The perspective view of 1st Embodiment. The principal part disassembled perspective view of 1st Embodiment. The principal part disassembled side view of 1st Embodiment. The principal part disassembled side view of 1st Embodiment. The principal part disassembled side view of 1st Embodiment. The perspective view of other embodiments.

[First Embodiment]
(Constitution)
The configuration of the first embodiment will be specifically described with reference to FIGS. 1 to 6. 1 is an exploded perspective view of the first embodiment, FIGS. 2 and 3 are perspective views of the first embodiment, and FIGS. 4 to 7 are exploded perspective views of essential parts of the first embodiment. In the description of the members shown in each drawing, the surface located on the upper side of the drawing is called the upper surface portion, and the lower surface of the drawing is called the bottom surface portion. However, the top surface portion and the bottom surface portion described here do not reflect the positional relationship when the coil is mounted on an actual machine.

  The coil 1 according to the first embodiment is applied to a coil for a vehicle-mounted noise filter or the like. As shown in FIGS. 1 to 3, the coil 1 includes a core 2 having a substantially rectangular parallelepiped shape, a U-shaped bus bar 3, a bobbin 4, and a tape 5 which is a belt-shaped member. Although the bobbin 4 is integrally molded with the bus bar 3, it is shown in a disassembled state in FIG. 2 and 3 show a state in which these members are assembled.

(Core 2)
The core 2 is composed of a dust core having a substantially rectangular parallelepiped shape. The core 2 having a substantially rectangular parallelepiped shape is provided with a top surface portion 21 and a bottom surface portion 22 that are parallel to each other, and a side surface portion 23 is provided as a flat surface portion perpendicular to the top surface portion 21 and the bottom surface portion 22. The top surface portion 21 and the bottom surface portion 22 are horizontal surfaces, and the side surface portion 23 is a surface with rounded corners. An insulating coating such as polyamide or polyester is not provided on the surface of the core 2, but an insulating coating may be provided on the surface of the core 2.

  The core 2 has two through holes 24, 24 penetrating the top surface portion 21 and the bottom surface portion 22. The through holes 24, 24 are parallel to each other and are rectangular holes with rounded corners. By opening these through holes 24, 24, the core 2 viewed from above has a "Sun" shape. The bus bar 3 integrally formed with the bobbin 4 is inserted into the through holes 24, 24 from below the core 2.

(Bus bar 3)
When the bus bar 3 is inserted into the through holes 24, 24 of the core 2, the upper half of the bus bar 3 is projected above the upper surface portion 21 of the core 2 (see FIGS. 2 and 3). As shown in FIGS. 1, 4 and 5, the bus bar 3 is a U-shaped member formed by flatwise bending, and is made of a single thin copper plate that is not insulation-coated. As described above, the bobbin 4 is integrally molded with the bus bar 3, but in the exploded views of FIGS. 1 and 5, the bus bar 3 and the bobbin 4 are shown separately to clarify the shape of the bus bar 3. ing. In FIG. 4, the bus bar 3 and the core 2 are shown.

  The U-shaped bus bar 3 is provided with two plate-shaped portions 31 that are parallel to each other and a connecting portion 32 that connects the plate-shaped portions 31 to each other. The plate-shaped portion 31 becomes a U-shaped long side portion. When the bus bar 3 is inserted into the through holes 24, 24 of the core 2, the portion protruding from the upper surface portion 21 of the core 2 is the upper half of the plate-shaped portion 31 of the bus bar 3.

  The upper half of the plate-shaped portion 31 is exposed with a copper plate without being insulated. An end portion of the plate-shaped portion 31 of the bus bar 3 is pulled out to be connected to a wiring (not shown) of an external device such as an external power source. When power is supplied to the bus bar 3 from an external power source, a current (indicated by a dotted arrow) flows through the U-shaped bus bar 3 to form a one-turn coil, which penetrates the bus bar 3 as shown in FIG. A magnetic flux (indicated by a solid arrow) is generated in the core 2 between the holes 24. As a result, the generated magnetic flux passes through the core 2 to form an annularly closed magnetic circuit.

(Bobbin 4)
The bobbin 4 is a member that insulates the core 2 and the bus bar 3 from each other, and is made of a molding resin integrally molded with the lower half of the bus bar 3. As shown in FIG. 1 and FIG. 5 to FIG. 7 of the exploded view, the bobbin 4 has two parallel sleeve portions 41, 41 protruding upward and a table portion for vertically raising the sleeve portions 41, 41. And 42 are provided. As shown in the lower side of FIG. 5, when the bobbin 4 is integrally molded in the lower half of the bus bar 3, the lower half of the plate-shaped portion 31 of the bus bar 3 is housed inside the sleeve portion 41. That is, the sleeve portion 41 of the bobbin 4 insulates the lower half of the plate-shaped portion 31 of the bus bar 3.

  Since the sleeve portion 41 of the bobbin 4 covers the plate-shaped portion 31 of the bus bar 3, it has a plate shape slightly thicker than the plate-shaped portion 31. The shape of the square holes of the through holes 24, 24 of the core 2 is formed so that the sleeve portions 41, 41 having such a shape can be inserted. In addition, as shown in FIG. 2, when the bus bar 3 is inserted into the through holes 24, 24 of the core 2, the tip of the sleeve portion 41 slightly projects from the upper surface portion 21 of the core 2.

  The table portion 42 of the bobbin 4 is adapted to insulatively cover the connecting portion 32 of the bus bar 3. The upper surface side of the table portion 42 is an abutting surface 43. The abutting surface 43 is a surface facing the core 2 in a portion of the bobbin 4 that covers the coupling portion 32 of the bus bar 3, and is a core when the plate-shaped portion 31 of the bus bar 3 is inserted into the through holes 24 of the core 2. 2 is a surface that abuts the entire bottom surface portion 22 of 2.

  Protruding portions 44 that project outward of the core 2 are formed at the left and right ends of the table portion 42 in the figure. The overhanging portion 44 is provided on the abutting surface 43 that is a portion of the bobbin 4 that covers the connecting portion 32 of the bus bar 3. The projecting portion 44 is configured to project from the bobbin 4 so that at least a portion around which the tape 5 is wound has the same outer shape as the core 2. The overhanging portion 44 is located outside the sleeve portion 41, and is provided integrally with the table portion 42. As shown in FIGS. 3 and 7, a square hole 45 is formed in the center of the table portion 42. The connecting portion 32 of the bus bar 3 is exposed from the hole 45.

  Further, as shown in FIGS. 1 to 7, a groove portion 46 into which the tape 5 is fitted is formed on the side surface portion and the bottom surface portion of the table portion 42. The groove portion 46 is set to have a dimension slightly wider than the width dimension of the tape 5. Further, the groove portion 46 is formed in the end portion of the groove portion 46 corresponding to the side surface portion of the table portion 42 so as to have a curved R shape. The groove portion 46 is formed to be recessed in the table portion 42, and the depth thereof is set deeper than the thickness dimension of the tape 5.

(Tape 5)
The tape 5 is a non-conductive adhesive tape made of a polyester film or the like. The tape 5 fixes the bus bar 3 having the plate-shaped portion 31 inserted in the through hole 24 to the core 2 together with the bobbin 4. The tape 5 is attached from the upper surface portion 21 of the core 2 to the side surface portion 23 of the bobbin 4 over the side surface portion and the bottom surface portion of the bobbin 4. It is supposed to be.

(Assembly of coil 1)
The first embodiment described above is assembled as follows. By molding the bobbin 4 on the bus bar 3, the bobbin 4 is integrally molded on the lower half of the bus bar 3. The sleeve portion 41 of the bobbin 4 is inserted into the through holes 24, 24 of the core 2 from the bottom surface 22 side of the core 2. The bobbin 4 and the core 2 are positioned by abutting the abutting surface 43 of the bobbin 4 on the bottom surface portion 22 of the core 2. As a result, the bobbin 4 and the bus bar 3 are inserted into the through holes 24, 24 of the core 2, and the coil 1 becomes a one-turn through coil.

  Then, the tape 5 is attached so as to go around the table portion 42 of the bobbin 4 from the upper surface portion 21 of the core 2 to the table portion 42 of the bobbin 4 through the side surface portion 23. As a result, the tape 5 fixes the bus bar 3 and the bobbin 4 to the core 2. When the tape 5 is wound around the table portion 42 of the bobbin 4, the tape 5 is in a state of being fitted in the groove portion 46.

  In the present embodiment, the coil 1 is housed in a case (not shown) for heat dissipation and is filled with a filler. The case is a metal container that houses the coil 1, and has a substantially rectangular parallelepiped shape with an open top and a hollow interior. The case is preferably made of a metal having a high thermal conductivity and a light weight, such as aluminum or an aluminum alloy. A filler is filled and solidified in the case to radiate the heat generated in the coil 1. That is, the filling molding part formed by solidifying the filling material is provided in the gap between the case and the coil 1. A relatively soft resin having a high thermal conductivity is suitable for the filler in order to secure the heat radiation performance of the coil 1.

(Action and effect)
The operation and effect of the first embodiment are as follows.
(1) The coil 1 according to the first embodiment includes a core 2 provided with two through holes 24, 24, two plate-like portions 31 that are parallel to each other, and a connecting portion 32 that connects the plate-like portion 31. Tape for fixing the U-shaped bus bar 3 having the above, the bobbin 4 that insulates the core 2 and the bus bar 3, and the bus bar 3 having the plate-shaped portion 31 inserted into the through hole 24 of the core 2 to the core 2 together with the bobbin 4. 5 and.

  According to such a first embodiment, the plate-like portion 31 of the bus bar 3 insulated by the bobbin 4 is inserted into the through holes 24, 24 of the core 2, and the tape 5, the core 2, the bus bar 3, and the bobbin 4 are inserted. The coil 1 having a one-turn through shape can be easily manufactured by simply fixing the coil. Therefore, as a fixing structure for the bus bar 3 and the core 2, a retaining shape of the bus bar 3 or the like is unnecessary. As a result, the structure can be simplified and the coil 1 can be made compact.

  Further, in the first embodiment, since it is not necessary to provide the busbar 3 with a retaining shape, the insulation coating of the bobbin 4 integrally formed with the busbar 3 even if the busbar 3 is pulled by an external force. There is no concern that the part will be damaged or the core 2 will be damaged. Therefore, the coil 1 can obtain excellent reliability.

  Furthermore, in the first embodiment, the bus bar 3 and the core 2 are fixed to each other only by winding the tape 5 around the bus bar 3. Therefore, it is not necessary to use an adhesive agent to fix the bus bar 3 and the core 2. Therefore, the time until the bus bar 3 and the core 2 are fixed can be shortened. Moreover, a jig for fixing the bus bar 3 and the core 2 and equipment for hardening the adhesive are not required at all. Therefore, the assembling work is facilitated, the cost is reduced, and the inexpensive coil 1 can be provided.

(2) In the first embodiment, the bus bar 3 is made of a U-shaped member formed by flatwise bending a copper plate. Therefore, the plate-shaped portion 31 of the bus bar 3 is different from the through hole 24 of the core 2 which is a square hole. Can be inserted smoothly. Therefore, the coil 1 is easy to assemble. Further, since the bus bar 3 is a member formed by flatwise bending a copper plate, the production cost is low and it is easy to make it compact. Therefore, it is possible to reduce the size and cost of the coil 1.

(3) Since the core 2 of the first embodiment has the side surface portion 23 as the flat surface portion with which the tape 5 is in contact, the tape 5 is bonded to the side surface portion 23 as compared with the case where the surface in contact with the tape 5 is a curved surface. Power becomes high. Therefore, the tape 5 can exhibit a high fixing force. Therefore, the tape 5 securely fixes the bus bar 3 and the bobbin 4 to the core 2, and the assembly reliability of the coil 1 is improved.

(4) In the bobbin 4 of the first embodiment, the sleeve portion 41 can be inserted into the through hole 24 of the core 2 and can accommodate the plate-shaped portion 31 of the bus bar 3, so that the through hole 24 of the core 2 It is easy to insert the plate-shaped portion 31 of the bus bar 3 insulated by the bobbin 4 into 24. Therefore, the coil 1 having a one-turn through shape can be manufactured more easily.

(5) In the first embodiment, since the bobbin 4 made of the molding resin is integrally formed with the U-shaped bus bar 3, the dimensional tolerance can be reduced as a whole. Therefore, the assemblability of the coil 1 is further improved.

(6) In the first embodiment, when the plate-like portion 31 of the bus bar 3 is inserted into the through hole 24 of the core 2, the abutting surface 43 of the bobbin 4 is simply abutted against the entire bottom surface portion 22 of the core 2, The core 2 and the bus bar 3 can be easily positioned. Therefore, it is possible to improve the assembly work efficiency of the coil 1.

(7) In the first embodiment, in the table portion 42 of the bobbin 4, the portion of the bobbin 4 that covers the connecting portion 32 of the bus bar 3 has the projecting portion 44 that projects toward the outside of the core 2. Can be stably placed on a flat surface. Such stable arrangement of the bobbin 4 improves the working environment for assembling the coil 1. Moreover, since the protruding portion 44 is provided at a position outside the sleeve portion 41, the dead space formed inside from the side surface which is the outer surface of the core 2 can be effectively utilized. Therefore, in the first embodiment, even if the overhanging portion 44 is provided, the coil 1 is not likely to increase in size, and only the advantage of improving the stability by the overhanging portion 44 can be obtained.

(8) The overhanging portion 44 is configured to overhang from the bobbin 4 so that at least the portion around which the tape 5 is wound has the same outer shape as the core 2. Therefore, the tape 5 extends to the side surface of the core 2 and the bobbin 4. It is possible to prevent the foreign matter from entering the gaps between the tape 5, the core 2 and the bobbin 4 by closely contacting each other. Particularly, when the tape 5 is an adhesive tape, foreign matter is likely to adhere to the adhesive tape. Therefore, it is effective for the tape 5 to be in close contact with the side surface portion of the core 2 and the bobbin 4 for preventing foreign matter from entering.

(9) In the first embodiment, the hole 45 of the bobbin 4 exposes the connecting portion 32 of the bus bar 3, so that the bus bar 3 can be efficiently radiated. Therefore, the coil 1 can stably exhibit predetermined characteristics.

(10) In the first embodiment, the groove portion 46 provided in the table portion 42 of the bobbin 4 serves as a guide, and the tape 5 is easily wound around the lower surface side of the table portion 42 of the bobbin 4. Further, since the groove portion 46 is formed so that the end portion has a curved R shape, the tape 5 is more easily wound around the table portion 42 of the bobbin 4. Furthermore, since the position where the tape 5 is wound is inside the side surface which is the outer surface of the bobbin 4 by providing the groove 46 in the bobbin 4, the coil 1 can be miniaturized. Furthermore, when the bobbin 4 is located on the bottom surface side in the coil 1, the bobbin 4 is located at a position facing the heat dissipation surface, so that heat dissipation is further improved.

  Moreover, in the first embodiment, the depth of the groove portion 46 is set to the depth into which the tape 5 is fitted, so that the tape 5 does not protrude from the lower surface of the table portion 42. Therefore, the assembled coil 1 can be stably placed on a plane, and the efficiency of assembling the coil 1 can be further improved.

(11) In the first embodiment, since the tape 5 is the adhesive tape, the work of fixing the bus bar 3 and the core 2 can be performed simply and quickly. Therefore, the assembly work of the coil 1 is further improved.

[Other Embodiments]
The present invention is not limited to the above embodiment. It can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope of the invention, the gist, and the scope of equivalents thereof.

  For example, a heat dissipation member may be provided so as to be in contact with the bus bar 3. Specifically, as shown in FIG. 7, the heat dissipation sheet 6 may be pressure-bonded to the entire lower surface of the table portion 42 of the bobbin 4. The heat dissipation sheet 6 contacts the connecting portion 32 of the bus bar 3 through the hole 45. According to such an embodiment, the heat dissipation sheet 6 can efficiently dissipate heat from the bus bar 3, and the coil 1 can more stably exhibit predetermined characteristics.

  Further, the outer shape of the core 2 does not have to be a rectangular parallelepiped shape, may be an outer shape including a curved surface, or two E-shaped cores may be combined. Further, although the core 2 of the above embodiment is the dust core, a magnetic material such as a ferrite core or a laminated steel plate may be used. Further, in the above embodiment, the bobbin 4 is integrally formed with the bus bar 3, but the bobbin 4 may be integrally formed with the core 2 side.

  The bobbin 4 may be any member that insulates the core 2 from the bus bar 3, and the type of insulating resin may be, for example, epoxy resin, unsaturated polyester resin, urethane resin, or the like, and can be appropriately selected. The bobbin 4 may be separate from the bus bar 3. In the embodiment in which the bobbin 4 and the bus bar 3 are separate bodies, the bobbin 4 can be manufactured at low cost.

DESCRIPTION OF SYMBOLS 1 ... Coil 2 ... Core 21 ... Top part 22 ... Bottom part 23 ... Side part 24 ... Through hole 3 ... Bus bar 31 ... Plate part 32 ... Connection part 4 ... Bobbin 41 ... Sleeve part 42 ... Table part 43 ... Abutting surface 44 ... Overhanging part 45 ... Hole 46 ... Groove 5 ... Tape 6 ... Heat dissipation sheet

Claims (13)

A core with two through holes,
A U-shaped bus bar having long side portions facing each other and a connecting portion connecting the long side portions;
A bobbin that insulates the core and the bus bar,
A coil, comprising: a strip-shaped member that fixes the bus bar, in which the long side portion is inserted into a through hole of the core, to the core together with the bobbin.   The coil according to claim 1, wherein the bus bar is made of a U-shaped member formed by flatwise bending a metal plate.   The coil according to claim 1 or 2, wherein the core has a flat portion in contact with the strip-shaped member.   The coil according to claim 1, wherein the bobbin includes a sleeve portion that can be inserted into the through hole of the core and that can accommodate the plate-shaped portion of the bus bar.   The coil according to any one of claims 1 to 4, wherein the bobbin is made of a molding resin integrally molded with the bus bar.   A portion of the bobbin that covers the connecting portion of the bus bar and faces the core has a portion that covers the connecting portion of the bus bar of the bobbin when the long side portion of the bus bar is inserted into the through hole of the core. The coil according to claim 1, further comprising an abutting surface that abuts the core.   7. The coil according to claim 1, wherein a portion of the bobbin that covers the connecting portion of the bus bar has a projecting portion that projects toward the outside of the core.   The coil according to claim 7, wherein the projecting portion is configured to project from the bobbin so that at least a portion around which the strip-shaped member is wound has the same outer shape as the core.   The coil according to any one of claims 1 to 8, wherein the bobbin has a hole in which a connecting portion of the bus bar is exposed.   The coil according to claim 1, wherein the bobbin has a groove portion into which the strip-shaped member is fitted.   The coil according to claim 10, wherein the groove portion has a curved surface formed at an end thereof.   The coil according to any one of claims 1 to 11, wherein the strip-shaped member is an adhesive tape.   The coil according to any one of claims 1 to 12, wherein a heat dissipation member is provided so as to be in contact with the bus bar.

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