JP2006102758A - Method for manufacturing coil having deformed cross section - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a coil having a deformed cross section by which the cost is reduced and also the coil having the deformed cross section is stably manufactured while preventing the approximately helically wound shape of a wire from disturbing by press forming. <P>SOLUTION: By this manufacturing method for the coil having the deformed cross section, the coil 1 is manufactured by dividing the coil 1 having the deformed cross section into a plurality ( two, for example ) of sections A1, A2, manufacturing intermediate coil bodies B1, B2 which are approximately stumpy for every respective sections A1, A2 and connecting them in the axial direction after press-forming them into an approximately truncated pyramidal shape. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a modified cross-sectional coil suitable for a motor of a hybrid vehicle or an electric vehicle.

  In order to increase the efficiency and output of drive motors for hybrid vehicles and electric vehicles, it is effective to improve the space factor of the motor coils. As a method for improving the space factor, a method of changing the cross-sectional shape of the wire according to the position on the winding path of the coil has been proposed, whereas the conventional wire having a constant cross-sectional shape is wound (Patent Literature). 1).

JP-A-7-274422

  However, in the above-described conventional technology, since a coil having a modified cross section is manufactured by winding a wire having a modified cross section whose cross-sectional shape changes with respect to the longitudinal direction, it is necessary to manufacture a wire having a modified cross section, and the manufacturing cost is high. There is a problem.

  Therefore, the problem to be solved by the present invention is that the low profile cost can be achieved, and the irregular cross-section coil that can stably produce the irregular cross-section coil while preventing the disorder of the substantially spiral winding form of the wire rod by press molding It is to provide a manufacturing method.

  In order to solve the above problems, in the invention of claim 1, a step of producing a plurality of types of intermediate coil bodies by winding a wire in a substantially spiral shape, and press-molding each of the intermediate coil bodies in its axial direction And a step of arranging the plural types of press-molded intermediate coil bodies in a line in the axial direction and connecting the wires of the intermediate coil bodies adjacent to each other.

  Further, in the invention of claim 2, it has a substantially truncated cone-shaped appearance, and the cross-sectional shape of the wire rod is gradually changed flat from the small-diameter end to the large-diameter end of the coil. In the method for manufacturing a coil, the deformed cross-section coil is divided into a plurality of sections in the axial direction, and an intermediate coil body having a substantially cylindrical shape to form each section is formed, and a wire corresponding to each section is formed in a substantially spiral shape. And a step of forming each type of intermediate coil body into a substantially truncated cone-shaped external form by pressing in the axial direction by changing the molding die for each corresponding section. And a step of arranging the press-molded plural types of intermediate coil bodies continuously in the axial direction and connecting the wires of the intermediate coil bodies adjacent to each other.

  According to a third aspect of the present invention, in the method for manufacturing a modified cross-section coil according to the second aspect of the present invention, the wire rod when the wire material is wound in a substantially spiral shape to produce the intermediate coil body includes the deformed coil. As the intermediate coil body corresponding to the section on the larger diameter side of the cross-sectional coil, a wire having a flat cross-sectional shape is used.

  According to the first aspect of the present invention, since a plurality of types of intermediate coil bodies are separately press-formed and then connected in the axial direction, a deformed cross-section coil is manufactured. Therefore, it is not necessary to use a wire with an irregular cross section, and the manufacturing cost can be reduced, and a deformed cross sectional coil can be stably produced while preventing a substantially spiral winding form of the wire from being disturbed by press molding. As a result, for example, when an insulating material is applied to the coil, the insulating film can be made uniform and prevented from peeling off.

  According to the second aspect of the present invention, since each of the intermediate coils is manufactured by separately forming a plurality of types of intermediate coil bodies having a substantially cylindrical shape and then connecting them in the axial direction, It is not necessary to use a wire with an irregular cross section as the wire for forming the body, and the manufacturing cost can be reduced.

  In addition, since the deformed cross-section coil is divided into a plurality of sections, an intermediate coil body is produced for each section, and the intermediate coil bodies are press-formed and then connected. As a result, the amount of deformation required when the intermediate coil body in each section (particularly, the section on the large diameter side of the deformed section coil) is press-molded can be reduced. be able to. This makes it possible to stably manufacture the irregular cross-section coil while preventing the substantially spiral winding form of the wire from being disturbed by press molding. As a result, for example, when an insulating material is applied to the coil, the insulating film can be made uniform and prevented from peeling off.

  According to the third aspect of the present invention, a wire rod having a flat cross-sectional shape is used as the intermediate coil body corresponding to the section on the larger diameter side of the deformed cross-section coil. Therefore, it is possible to reduce the amount of deformation required when press-molding the intermediate coil body in each section (particularly, the section on the large-diameter side of the irregular cross-section coil). It is possible to stably manufacture a deformed cross-section coil while preventing the winding form of the shape from being disturbed.

<Related technology>
First, in describing an embodiment according to the present invention, a related technique that serves as a reference will be described. This related technique is a non-known technique.

  FIG. 6 is a perspective view of a coil to which the method for manufacturing a modified cross-section coil according to the present invention is applied. As shown in FIG. 6, the irregular cross-section coil (hereinafter simply referred to as “coil”) 1 has a substantially truncated cone-shaped appearance, and the cross-sectional shape of the wire 3 is on the small diameter side (the bottom of FIG. 6). Side) end gradually changes from the end to the end on the large diameter side (upper side in FIG. 6). At both ends of the coil 1, lead portions 5 and 7 for electrical connection are provided. Note that the coil 1 shown in FIG. 6 has an external appearance (substantially truncated quadrangular pyramid shape) in which a substantially quadrangular pyramid head is cut off.

  As a method for manufacturing such a coil 1, the following method (first related technique) has been proposed. First, as shown in FIG. 7, a substantially columnar intermediate coil body 11 is formed by spirally winding a wire 3 having a constant cross-sectional shape (for example, a substantially rectangular cross-sectional shape) around a core material 9. At this time, since the core material 9 has a certain substantially rectangular cross section, the intermediate coil body 11 having a substantially columnar shape is produced. Subsequently, as shown in FIG. 8, the intermediate coil body 11 is set in a molding die 13 and pressed in the axial direction to be molded.

  However, in the method of simply pressing and forming as shown in FIG. 8, the intermediate coil body 11 is bent and often cannot be formed well. FIG. 9A to FIG. 9C are schematic views showing stepwise progress in the mold during pressing by the method shown in FIG. 8, and show a case where buckling occurs.

The causes of the buckling are as follows: (a) A large frictional force is generated between the upper mold 13a of the mold 13 and the intermediate coil body 11 due to an increase in the vertical drag force during pressing, and the outer diameter of the intermediate coil body 11 is reduced. The sufficient sliding movement of the enlarged upper end portion in the radial direction cannot be obtained, and (b) the intermediate coil body 11 is expanded in a barrel shape in the axial direction by the press. It is possible that the upper material is cramped and enters.

  Therefore, the inventor of the present application has proposed an improved technique (second related technique). In this related technology, a coil connecting body 21 having a substantially barrel-like appearance (here, a substantially rectangular barrel shape having a rectangular cross-sectional shape) as shown in FIG. 10 is produced, and the coil connecting body is produced. The two coils 1 having the substantially truncated cone-shaped external form shown in FIG. That is, the coil connecting body 21 is configured by continuously connecting two intermediate coil bodies 23A and 23B in the axial direction, and each of the divided intermediate coil bodies 23A and 23B becomes the coil 1. Hereinafter, this manufacturing method is referred to as a two-piece method.

  The coil connecting body 21 shown in FIG. 10 has a shape in which the upper and lower portions are substantially symmetrical with respect to the upside down with respect to the middle portion, and lead portions 25 and 27 for connecting electric wires at the upper and lower ends. And an overhanging portion 29 is formed in the middle portion so as to protrude outward in a substantially U shape in plan view. By cutting the projecting portion 29, the upper and lower portions can be easily divided, and the remaining projecting portion 29 can form a lead portion for electrical connection.

  The manufacturing method will be described. First, the coil connecting body 21 is manufactured. As shown in FIG. 11, the production is performed by winding the wire 3 around a predetermined core material 31 in a spiral shape. Since the core material 31 has a certain substantially rectangular cross section, the coil connecting body 21 having a substantially columnar shape is produced. Leading portions 25 and 27 are formed at the upper and lower ends of the coil connecting body 21, and an overhanging portion 29 is formed at the intermediate portion.

  Subsequently, as shown in FIG. 12, the produced coil connecting body 21 is set in the molding die 33 while being wound around the core material 31, and press molding is performed. The molding die 33 includes a pair of an upper die 35 and a lower die 37 that are disposed opposite to each other so as to form a substantially barrel-shaped (here, generally rectangular barrel-shaped) cavity 34 around the set core material 31. The upper die 35 is driven to the lower die 37 side by a press mechanism to perform press molding.

  When the upper die 35 is lowered from the state shown in FIG. 12 and pressing is performed, as schematically shown in FIGS. 13A to 13C as the upper die 35 is lowered in the forming die 33. The molding proceeds to the state shown in FIG. 13 (c). That is, when pressing starts, the intermediate portion of the coil connecting body 21 spreads outward in a substantially barrel shape as shown in FIG. 13 (a), as shown in FIGS. 13 (b) and 13 (c). Press molding is performed such that the outer periphery of the coil connecting body 21 is along the inner peripheral surface of the cavity 34 of the mold 33. In addition, the figure shown to Fig.13 (a) thru | or FIG.13 (c) is based on the analysis result by a computer.

  In the state shown in FIG. 13C where the pressing is completed, the coil connecting body 21 has a substantially barrel shape corresponding to the shape of the cavity 34 formed by the outer periphery of the core material 31 and the inner periphery of the mold 33. Molded into form. In addition, the code | symbol 39 shown in FIG. 12 is the escape part provided corresponding to the overhang | projection part 29. FIG.

  When the formation of the coil connecting body 21 is finished, the coil connecting body 21 is divided into two at the intermediate portion as described above, so that two coils 1 are produced.

  In such a two-piece manufacturing method, a substantially columnar coil connecting body 21 is press-formed into a substantially barrel shape by using a forming die 33, and then the coil connecting body 21 is divided into two parts to be substantially cut. Since the two conical head-shaped coils 1 are manufactured, the coil 1 can be manufactured stably without causing each portion of the coil connecting body 21 to bend during pressing. This is presumably due to the following reasons.

  That is, as a first reason, when the coil connecting body 21 is pressed, pressure is applied to the upper and lower ends of the coil connecting body 21 to generate a frictional force with the molding die 33. In the configuration molded into a shape, since sliding along the radial direction is not required between the upper and lower ends of the coil connecting body 21 and the molding die 33, the frictional force between the part and the molding die 33 does not matter. It is possible.

  As a second reason, as shown in FIGS. 13 (a) and 13 (b), the coil connecting body 21 at the time of pressing has an intermediate portion that spreads outward in a substantially barrel shape by free upsetting. Since the expanded part naturally follows the inner peripheral surface of the substantially barrel-shaped cavity 34, it is considered that the buckling hardly occurs from this point.

  However, in the manufacturing method according to the second related technology, when the coil connecting body 21 is press-molded, the amount of deformation of the intermediate portion in the axial direction of the coil connecting body 21 becomes excessively large, and the wire 3 in that portion is increased. There is a case where the substantially spiral winding form is disturbed to cause buckling or the like, and this countermeasure is required.

  Therefore, the inventor of the present application has invented a method for manufacturing a modified cross-section coil according to the following embodiment based on the above viewpoint.

<Embodiment>
In the method for manufacturing a modified cross-section coil according to an embodiment of the present invention, roughly as shown in FIG. 1, the coil 1 is divided into a plurality of (for example, two) sections A1 and A2, and each section A1 is divided. , A2 are produced for each A2, and the coil 1 is produced by connecting these intermediate coil bodies B1 and B2 in the axial direction. In the specific example described below, a configuration in which the coil 1 is divided into two parts will be described. However, the present invention is not limited to this, and the deformed cross-sectional coil 1 is divided into three or more parts. You may make it produce.

As shown in FIG. 1, FIG. 2 (a), FIG. 2 (b), FIG. 3 (a), and FIG.
(A) producing a plurality of types (two types) of coil connecting bodies C1 and C2,
(B) a step of press-forming each type of coil connecting body C1, C2, and
(C) dividing the press-formed coil connecting bodies C1 and C2, and
(D) connecting the intermediate coil bodies B1, B2;
have.

  In the step (a), as shown in FIG. 2 (a) and FIG. 3 (a), wire rods 41 and 43 corresponding to the respective sections A1 and A2 are predetermined as in the step shown in FIG. Two types of coil connecting bodies C1 and C2 are produced by winding the core members 45 and 47 in a substantially spiral shape. The coil connecting bodies C1 and C2 have a form in which two intermediate coil bodies B1, B1 and B2 and B2 are connected in the axial direction, and have a generally rectangular columnar appearance as a whole. Yes.

  Since the coil 1 has a configuration in which the cross-sectional shape of the wire 3 gradually changes from the small diameter side toward the large diameter side, the coil connecting body C2 corresponding to the section A2 on the large diameter side is produced accordingly. The wire 43 used in the above is used in which the cross-sectional shape is flatter than the wire 41 used for producing the coil connecting body C1 corresponding to the section A1 on the smaller diameter side (instead of having a small thickness, the lateral width is large). In addition, what has a fixed substantially rectangular cross section with respect to the longitudinal direction is used for the wire rods 41 and 43 at the time of producing the coil connection body C1 and C2.

  In the step (b), the steps shown in FIGS. 2 (a), 2 (b), 3 (a) and 3 (a) are substantially the same as the steps shown in FIGS. 12 and 13 (a) to 13 (c). As shown in FIG. 3B, press forming is performed on the coil connecting bodies C1 and C2. In this step, the coil connecting bodies C1 and C2 are wound around the core members 45 and 47 as shown in FIGS. 2A and 3A, and the forming dies 51 corresponding to the sections A1 and A2 are used. 53, and press molding is performed as shown in FIGS. 2 (b) and 3 (b). The molding dies 51 and 53 are a pair of upper dies 61 arranged vertically opposite each other to form cavities 55 and 57 having a substantially barrel shape (here, a substantially rectangular barrel shape) around the set core members 45 and 47. 63 and lower molds 65 and 67, and the upper molds 61 and 63 are driven to the lower molds 65 and 67 side by a press mechanism to perform press molding. The shapes of the upper half and the lower half of the cavities 55 and 57 of the respective molds 51 and 53 correspond to the shapes of the sections A1 and A2 of the corresponding coil 1.

  And by this press molding, coil connection body C1, C2 is shape | molded by the substantially rectangular barrel shape similar to the form shown in above-mentioned FIG.

  In the step (c), the coil connecting bodies C1 and C2 formed in a substantially rectangular barrel shape are divided at the intermediate portion in the axial direction, thereby two intermediate members having a substantially truncated cone-shaped appearance. It is divided into coil bodies B1 and B2.

  In the step (d), the two types of intermediate coil bodies B1 and B2 divided in the step (c) are connected in an axially arranged state as shown in FIG. In this connecting step, the large-diameter side end portion 67 of the wire rod 41 of the small-diameter side intermediate coil body B1 and the small-diameter side end portion 69 of the wire rod 43 of the large-diameter side intermediate coil body B2 are joined. As a result, the coil 1 as shown in FIG. 6 is manufactured.

  As described above, according to the present embodiment, a plurality of types (for example, two types) of intermediate coil bodies B1 and B2 having a substantially cylindrical appearance are separately formed by pressing and then deformed by connecting them in the axial direction. Since the cross-sectional coil 1 is manufactured, it is not necessary to use the wire members 41 and 43 having an irregular cross section as the wire members 41 and 43 when forming the intermediate coil bodies B1 and B2, and the manufacturing cost can be reduced.

  In addition, the coil 1 is divided into a plurality of (for example, two) sections A1 and A2, and intermediate coil bodies B1 and B2 are produced for each section A1 and A2, and each of the sections is formed after press forming. The intermediate coil bodies B1 and B2 can be manufactured using the wire members 41 and 43 having different cross-sectional shapes for each of the intermediate coil bodies B1 and B2 constituting the sections A1 and A2, and as a result, the sections A1 and A2 (particularly, The amount of deformation required when the intermediate coil bodies B1 and B2 in the section A2) on the large diameter side are press-molded can be reduced. Thus, the irregular cross-section coil 1 can be stably manufactured while preventing the substantially spiral winding form of the wires 41 and 43 from being disturbed by press molding. As a result, for example, when an insulating material is applied to the coil 1, it is possible to make the insulating film uniform and prevent peeling.

  In addition, since the wire rods 41 and 43 used when the intermediate coil bodies B1 and B2 are manufactured, the wire rod 43 having a flatter cross-sectional shape than the intermediate coil body B1 on the small diameter side is used for the intermediate coil body B2 on the large diameter side. The amount of deformation required when the intermediate coil body B2 in the section A2 is press-molded can be reduced, thereby preventing the substantially spiral winding form of the wire 43 from being disturbed by press molding. The coil 1 can be manufactured stably.

  In addition, the coil 1 manufactured in this way is inexpensive, and the wire 3 is more spiral than the coil 1 manufactured by the manufacturing method shown in FIGS. 12 and 13A to 13C. The winding form is maintained in a good state, and the form and performance are stable.

  In the present embodiment, the coil connecting bodies C1 and C2 in which the two intermediate coil bodies B1, B1 and B2, B2 are connected are configured, and are pressed to be divided into two intermediate coil bodies B1 and B2. As described above, the intermediate coil bodies B1 and B2 for one piece are manufactured as in the manufacturing method shown in FIGS. 8 and 9A to 9C, and the You may make it perform press molding for every intermediate coil body B1, B2.

  As another modified example, as shown in FIG. 4, wire end portions 67 and 69 which are connecting portions of the intermediate coil bodies B1 and B2 are formed by projecting radially outward from the coil body portion. May be.

<Application example>
Next, an application example of the coil 1 manufactured by the manufacturing method according to the above-described embodiment will be described. In this application example, as shown in FIG. 5, the coil 1 is incorporated in the stator core of the motor, and the plurality of coils 1 are externally attached to the plurality of cores 71 arranged at equal intervals in the circumferential direction. It is inserted and arranged.

It is explanatory drawing explaining the manufacturing process of the irregular cross-section coil which concerns on one Embodiment of this invention. FIG. 2A and FIG. 2B are explanatory views for explaining the manufacturing process of the intermediate coil body on the small diameter side. FIG. 3A and FIG. 3B are explanatory views for explaining a manufacturing process of the intermediate coil body on the large diameter side. It is a figure which shows the modification of the manufacturing method shown in FIG. It is a figure which shows the example of application of an irregular cross-section coil. It is a perspective view of the coil to which the manufacturing method of the irregular cross-section coil which concerns on this invention is applied. It is explanatory drawing of the formation process of an intermediate coil body. It is explanatory drawing of the manufacturing method of the irregular cross-section coil which concerns on a proposal example. FIG. 9A to FIG. 9C are explanatory views showing stepwise progress in the mold during pressing by the method of FIG. 7 and FIG. It is a perspective view of the coil connection body formed in the substantially barrel shape produced in the manufacture process by the manufacturing method of the odd-shaped section coil concerning other proposals. It is explanatory drawing of the formation process of a coil connection body. It is explanatory drawing when a coil connection body is press-molded. FIG. 13A to FIG. 13C are explanatory views showing in a stepwise manner the progress in the mold during pressing according to the proposed example of FIG.

Explanation of symbols

1 Modified cross-section coil 3, 41, 43 Wire material 9, 45, 47 Core material 11, 23A, 23B, B1, B2 Intermediate coil body 21, C1, C2 Coil connecting body 51, 53 Mold A1, A2 Section

Claims (3)

Producing a plurality of types of intermediate coil bodies by winding the wire in a substantially spiral shape; and
Pressing each intermediate coil body in its axial direction;
The press-molded plural types of intermediate coil bodies are arranged continuously in the axial direction, and the intermediate coil bodies adjacent to each other are connected to each other, and
The manufacturing method of the irregular cross-section coil characterized by the above-mentioned. In the method of manufacturing a modified cross-section coil that has a substantially truncated cone-shaped appearance, and the cross-sectional shape of the wire gradually changes from a small-diameter side end to a large-diameter side end of the coil,
The deformed cross-section coil is divided into a plurality of sections in the axial direction, and an intermediate coil body having a substantially cylindrical outer shape to form each section is produced by winding a wire corresponding to each section in a substantially spiral shape. Process,
Each of the types of intermediate coil bodies is formed in a substantially truncated cone-shaped appearance by pressing the axial direction of the corresponding mold by changing the molding die for each section, and
The press-molded plural types of intermediate coil bodies are arranged continuously in the axial direction, and the intermediate coil bodies adjacent to each other are connected to each other, and
The manufacturing method of the irregular cross-section coil characterized by the above-mentioned. In the manufacturing method of the irregular cross-section coil according to claim 2,
The wire used when the intermediate coil body is produced by winding the wire in a substantially spiral shape has a flatter cross-sectional shape as the intermediate coil body corresponding to the section on the larger diameter side of the deformed cross-section coil. A method of manufacturing a modified cross-section coil, wherein a wire is used.

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