JP4517715B2 - Method for manufacturing irregular cross-section coil - Google Patents

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 of 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.

  FIG. 18 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. 18, the coil 1 has a substantially truncated cone-shaped appearance, and the cross-sectional shape of the wire 3 is from the end on the small diameter side (the lower side in FIG. 18) to the large diameter side (see FIG. 18). It gradually changes to a flat shape toward the end of 18). 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. 18 has an external appearance (substantially truncated quadrangular pyramid shape) in which a substantially quadrangular pyramid head is cut off.

  As a manufacturing method of such a coil 1, as shown in FIG. 19, a wire rod 3 is spirally wound around a core member 9 to form a substantially columnar intermediate coil body 11, and the intermediate coil body 11 is formed. There has been proposed a method of forming in a mold 13 by pressing in the axial direction.

  However, in the method of simply pressing and forming shown in FIG. 19, the intermediate coil body 11 is buckled, and in many cases, it cannot be formed well. 20 (a) to 20 (c) are schematic views showing stepwise progress in the mold during pressing by the method shown in FIG. 19, 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 point that sufficient sliding movement to the outside in the radial direction of the enlarged upper end portion cannot be obtained, and (b) the middle portion of the intermediate coil body 11 spreads in a barrel shape by the press, so that the middle portion has spread. It is possible that the upper material is cramped and enters.

  The problem to be solved by the present invention is to provide a method of manufacturing a modified cross-section coil that can stably manufacture a modified cross-section coil.

In order to solve the above-mentioned problem, in the invention of claim 1, a coil body is formed by winding a wire rod in a spiral shape, and the cross-sectional shape perpendicular to the central axis , which is arranged to face each other in the press direction, is rectangular. a first mold for forming half of the substantially barrel-shaped cavity is, the coil body to a second mold to consist of the mold in forming the other half of the cavity, the axial direction of the press The coil body is axially pressed by the forming die, and the outer shape of the coil body is formed into a substantially barrel shape having a rectangular cross-sectional shape perpendicular to the central axis, and formed. one of said coil body after by 2 divided at its center, to create two coils modified cross-section.

Further, in the invention of claim 2, in the manufacturing method of irregular cross section coil according to the invention of claim 1, by forming stepwise the coil body by a plurality of times of press forming by the first and second type The coil having the irregular cross section is manufactured.

According to a third aspect of the present invention, in the method for manufacturing a modified cross-section coil according to the first or second aspect of the present invention, the first and second dies are simultaneously driven in a direction close to each other in the press forming step. And press molding.

Further, in the invention of claim 4, in the method for manufacturing a modified cross-coil according to any one of the claims 1 to 3, in the step of forming a pre-Kiko yl body, the wire is Ru series of wire Der .

Further, in the invention of claim 5, in the method for manufacturing a modified cross-coil according to any one of the claims 1 to 4, in the step of forming a pre-Kiko yl body, the wire is Ru constant cross-sectional shape der .

According to the first aspect of the present invention, the first mold that forms a half of the substantially barrel-shaped cavity that is disposed opposite to each other in the direction of the press and that has a rectangular cross-sectional shape perpendicular to the central axis , The coil body is placed in a molding die composed of a second die forming the other half so that its axial direction coincides with the pressing direction, and the coil body is pressed in the axial direction by the molding die. The outer shape of the coil body is formed into a substantially barrel shape . Then , two coils having irregular cross sections are created by dividing the single coil body after molding into two at the center . Therefore, the deformed cross-section coil can be manufactured stably without the coil body being bent during pressing.

According to the second aspect of the present invention, by forming the coil body in stages using the first and second molds , even if the coil body has a large degree of deformation due to the molding , the coil body can be bent. It can be manufactured stably without being generated.

According to the invention of claim 3, the outer shape of the coil body can be finished symmetrically and accurately by driving the first and second molds simultaneously in the directions close to each other and performing press molding, It is possible to manufacture a modified cross-section coil having a more uniform shape.

According to the invention of claim 4, co Since yl body is formed from a series of wire, coils bodies manufactured easily and efficiently can be carried out, its results, easily and efficiently modified cross-section coil Can be manufactured.

According to the invention of claim 5, for use wires of constant cross section, it is easy to control the cross-sectional shape at the time of wire production, easy control of winding force even during the production of or coils thereof Therefore, it is possible to easily manufacture a coil body and, consequently, a coil having an irregular cross section.

<First Embodiment>
In the method for manufacturing a modified cross-section coil according to the first embodiment of the present invention, the cross-sectional shape is generally barrel-shaped as shown in FIG. 1, and the cross-sectional shape perpendicular to the barrel shape is a rectangular shape. A coil connecting body 21 having a rectangular barrel- shaped appearance is produced from a series of wires 3 . Then, by 2 divides the coil connecting member 21 at the central portion in the axial direction, each of which produce a coil 1 of the two modified cross section with the appearance form of a substantially truncated cone shape shown in FIG. 18 described above. That is, the outer surface shape of the coil connecting member 21 has two irregular cross section of the coil 23A, has a shape such that the axial direction had been continuously the 23B, if divide it, the two irregular cross section coil 23A and 23B are obtained as the coil 1 having an irregular cross section .

  The coil connecting body 21 shown in FIG. 1 has a shape in which the upper and lower portions are substantially symmetrical with respect to the upside down with respect to the center portion, and lead portions 25 and 27 for connecting the wires to the upper and lower ends. A protruding portion 29 is formed in the central 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 according to this embodiment will be described in detail below.

First, the coil connecting body 21 is manufactured. As shown in FIG. 2, the production is performed by winding a wire 3 having a constant cross-sectional shape (for example, a substantially rectangular cross-sectional shape) around a predetermined core material 31 spirally. 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 central portion.

Subsequently, as shown in FIG. 3, the produced coil connecting body 21 is set in the forming die 33 while being wound around the core material 31, and press forming is performed. The molding die 33 has a shape in which the distance from the central axis to the outer side gradually increases as it goes from the both ends of the central axis to the central part as a cross-sectional shape passing through the central axis around the set core material 31. It has a pair of an upper die 35 and a lower die 37 that are arranged opposite to each other to form a cavity 34 (here, a substantially rectangular barrel shaped cavity 34). Press molding is performed by driving the upper die 35 toward the lower die 37 by a press mechanism 47 (see FIG. 6). The detailed configuration of the mold 33 and the like will be described later. In the present embodiment, the molding die 33 is configured by the upper die 35 and the lower die 37 that are opposed to each other vertically . For example, with respect to the arrangement state of the components shown in FIGS. , if the horizontal direction replaces the vertical direction may be using a mold 33 constituting the other pair of dies arranged opposite to horizontal direction direction.

  When the upper die 35 is lowered from the state shown in FIG. 3 and pressing is performed, in the forming die 33, as schematically shown in FIGS. 4 (a) to 4 (c) as the upper die 35 is lowered. The molding proceeds to the state shown in FIG. 4 (c) and FIG. That is, when the press starts, the central portion of the coil connecting body 21 spreads outward in a substantially barrel shape as shown in FIG. 4A, and as shown in FIGS. 4B and 4C. 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. 4 (a) to 4 (c) and FIG. 5 are based on the results of analysis by a computer.

  Here, regarding the core material 31, the core material 31 when the wire 3 is wound around the core material 31 to produce the coil connecting body 21 and the core material 31 installed in the mold 33 together with the coil connecting body 21 are: It may be different.

  In the state shown in FIG. 5 where the pressing is completed, the coil connecting body 21 is formed into 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 forming die 33. Is done. In addition, the code | symbol 57b shown in FIG.3 and FIG.5 is the escape part provided corresponding to the overhang | projection part 29 (it mentions later for details).

  When the formation of the coil connecting body 21 is completed, the coil connecting body 21 is divided into two at the center as described above, thereby producing the coil 1 having two irregular cross sections.

  6 is a right side view showing the overall configuration of the press molding machine used in the manufacturing method according to the present embodiment, FIG. 7 is a front view of the periphery of the die unit of the press molding machine, and FIG. It is a top view of a mold unit periphery.

  As shown in FIGS. 6 to 8, the press molding machine 41 includes a die unit 43, a base 45, and a press mechanism 47. The mold unit 43 includes the mold 33 and a holder 51 that surrounds and holds the mold 33 and is installed on the base 45.

  The upper die 35 and the lower die 37 of the molding die 33 have substantially symmetrical shapes with respect to the upside down, and form upper and lower halves of the substantially barrel-shaped cavity 34. The upper mold 35 includes an upper mold body 53 and an upper lid 55, and the lower mold 37 includes a lower mold body 57 and a lower lid 59.

  As shown in FIGS. 9 (a) to 9 (c), the upper mold body 53 is provided with a cavity forming section 53a that forms the cavity 34 together with the lower mold body 57, and the lower surface side (up and down) A concave relief portion 53b for the projecting portion 29 of the coil connecting body 21 is formed in the peripheral portion of the cavity forming portion 53a in the inverted arrangement state of FIG. Further, a groove-shaped escape portion 53 c for the upper drawing portion 25 is formed on the upper surface side of the upper mold main body portion 53. Such an upper mold main body 53 is divided into two blocks 53A and 53B along a dividing line L1.

  Here, the escape portion 53b is provided in a substantially L shape in plan view so as to correspond to about half of the overhanging portion 29 that is substantially U-shaped in plan view. The entire extended portion 29 is covered by the entire escape portions 53b and 57b in a continuous manner with 57b.

  As shown in FIGS. 10 (a) and 10 (b), the upper lid portion 55 is provided with a through hole 55a through which the core material 31 is inserted, and its lower surface side (upside down in FIG. 10 (a)). On the upper surface side in the arrangement state, a convex portion 55b is provided for denting the side portion 61 of the portion where the lead portion 25 is provided at the upper end portion of the coil connecting body 21. By this convex part 55b, the part of the coil connecting body 21 where the lead part 25 is provided can be formed into a substantially flat form without difficulty.

  As shown in FIGS. 11A to 11C, the lower mold body 57 is provided with a cavity forming part 57 a that forms a cavity 34 together with the upper mold body 53, and the cavity on the upper surface side thereof is provided. A concave relief portion 57b for the overhang portion 29 of the coil connecting body 21 is formed in the periphery of the formation portion 57a. Further, on the lower surface side of the lower mold main body portion 57, a groove-shaped escape portion 57c for the lower drawing portion 27 is formed. Similar to the upper mold body 53, the lower mold body 57 is composed of two blocks 57A and 57B divided by a dividing line L2.

  As shown in FIGS. 12 (a) and 12 (b), the lower lid portion 59 is provided with a through hole 59a through which the core material 31 is inserted, and on the upper surface side thereof, the lower end of the coil connecting body 21 is provided. Convex part 59b for denting the side part 63 of the part in which the drawer part 27 is provided in the part is provided.

  As shown in FIG. 6, the press mechanism 47 includes a pressure punch 65 that applies a compressive force downward to the mold 33 of the mold unit 43, and a drive mechanism (not shown) that drives the pressure punch 65. Yes. The pressure punch 65 is connected to a drive mechanism via a punch holder 67 and a shank 69.

  As described above, in the present embodiment, the substantially columnar coil connecting body 21 is press-formed into a substantially barrel shape by using such a press molding machine 41, and then the coil connecting body 21 is divided into two parts to be approximately. Since the two coils 1 having a truncated pyramid shape are manufactured, the coil 1 having a deformed cross section can be stably manufactured 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 structure to be molded, no sliding along the radial direction is required between the upper and lower ends of the coil connecting body 21 and the molding die 33, so that the frictional force between this part and the molding die 33 does not matter. Can be considered.

Further, as the second reason, the coil connecting member 21 at the time of pressing, as shown in FIG. 4 (a) and 4 (b), outwardly in a substantially barrel-shaped central portion in the axial direction by upsetting the free Although it spreads, the spread is naturally along the inner peripheral surface of the substantially barrel-shaped cavity 34, and it is considered that buckling is less likely to occur from this point.

Further, according to this embodiment, a coil connecting member 21, because formed from a series of wire 3, it is possible to carry out the fabrication of the coil connecting member 21 easily and efficiently, as a result, the modified cross-section coil 1 Can be manufactured easily and efficiently.

In addition, according to the present embodiment, since the coil connecting body 21 is manufactured using the wire 3 having a constant cross-sectional shape, it is easy to control the cross-sectional shape at the time of manufacturing the wire 3, and when the coil connecting body 21 is manufactured. However, since it is easy to control the wrapping force, the coil connecting body 21 can be manufactured, and thus the coil 1 having an irregular cross section can be easily manufactured.

<Second Embodiment>
Next, a method for manufacturing a modified cross-section coil according to the second embodiment of the present invention will be described.

  First, the reason why the manufacturing method according to this embodiment is required will be described. That is, when the degree of form change before and after forming is large (when the degree of forming is large), if the coil connecting body 21 is formed by a single press forming, buckling occurs as shown in FIG. There are many cases where molding cannot be performed well. In the example shown in FIG. 13, buckling occurs at the portions indicated by arrows A1 and A2. Note that the diagrams shown in FIG. 13 and FIGS. 14A to 14D described later are based on the results of analysis by a computer.

  Therefore, in the present embodiment, as shown in FIGS. 14A to 14D, the coil connecting body 21 is press-molded a plurality of times (using two (here, two) molding dies 33A and 33B). Here, it is performed step by step in two steps. The molding die 33A used in the first molding has a cavity 34A set in a substantially barrel shape at an intermediate stage, and the molding die 33B used in the second molding is a coil connecting body to be molded. 21 has a cavity 34B set in a substantially barrel shape corresponding to 21 final forms.

Then, as shown in FIGS. 14A and 14B, the substantially columnar coil connecting body 21 is press-molded into a substantially barrel shape at an intermediate stage by a molding die 33A. Subsequently, as shown in FIGS. 14 (c) and 14 (d), the coil connecting body 21 formed in the intermediate stage is press-molded into a final barrel shape by the molding die 33B.

  Therefore, according to the present embodiment, substantially the same effect as in the case of the first embodiment can be obtained, and by performing press molding step by step using a plurality of molding dies 33A and 33B, deformation due to molding can be achieved. Even the coil 1 having a large irregular cross section can be stably manufactured without causing buckling or the like.

<Third Embodiment>
FIG. 15 is an explanatory diagram of a method for manufacturing a modified cross-section coil according to the third embodiment of the present invention. The manufacturing method according to this embodiment is different from the manufacturing methods according to the first and second embodiments described above in that both the upper die 35 and the lower die 37 of the molding die 33 are driven to perform press molding. These are only the points and related points, and the corresponding parts are denoted by the same reference numerals and the description thereof is omitted.

  In this embodiment, as indicated by arrows A3 and A4 in FIG. 15, the coil connecting body 21 is driven by simultaneously driving both the upper mold 35 and the lower mold 37 of the mold 33 in directions close to each other at substantially the same speed. The press molding is performed. The upper die 35 and the lower die 37 are driven by upper and lower pressure punches (not shown).

  By doing so, the same compressive force can be applied to the upper and lower portions of the coil connecting body 21 during pressing, and the shape of the upper and lower portions of the formed coil connecting body 21 can be prevented from becoming asymmetric. . FIG. 16 shows the result of computer analysis when the method according to the present embodiment is applied to the second embodiment, and a molding shape better than the analysis result of FIG. I understand that.

  Therefore, according to the present embodiment, substantially the same effects as those of the first and second embodiments can be obtained, and the substantially barrel-shaped finished form of the coil connecting body 21 can be accurately finished in a vertically symmetrical manner. Thus, the coil 1 having an irregular cross section with a more uniform shape can be manufactured.

<Application example>
Next, an application example of the coil 1 having an irregular cross section manufactured by the manufacturing method according to each of the above embodiments will be described. In this application example, as shown in FIG. 17, the coil 1 is incorporated in the stator core of the motor, and the plurality of coils 1 are inserted into the plurality of cores 71 arranged at equal intervals in the circumferential direction. Arranged.

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 a 1st embodiment of the present invention. 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. 4A to FIG. 4C are explanatory views showing the progress in the middle of the mold during pressing step by step. It is explanatory drawing which shows the state in the shaping | molding die at the time of press completion. It is a right view which shows the whole structure of a press molding machine. It is a front view of the mold unit periphery of the press molding machine of FIG. It is a top view of the mold unit periphery of FIG. FIG. 9A to FIG. 9C are a plan view, a right side view, and a front view of a state in which the upper mold main body portion is disposed with the lower surface side facing upward. FIG. 10A and FIG. 10B are a plan view and a right side view of a state in which the upper lid portion is disposed with its lower surface side facing upward. 11 (a) to 11 (c) are a plan view, a right side view, and a front view of the lower mold main body. 12A and 12B are a plan view and a right side view of the lower lid portion. It is explanatory drawing which shows the state which the buckling produced in the coil connection body by press molding. 14 (a) to 14 (d) are explanatory views showing manufacturing steps of a method for manufacturing a modified cross-section coil according to the second embodiment of the present invention. It is explanatory drawing of the manufacturing method of the irregular cross-section coil which concerns on 3rd Embodiment of this invention. It is a figure which shows the result of the computer analysis at the time of applying the method which concerns on 3rd Embodiment to 2nd Embodiment. 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 manufacturing method of the irregular cross-section coil which concerns on a proposal example. 20 (a) to 20 (c) are explanatory views showing stepwise progress in the mold during pressing by the method of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Coil 3 Wire material 21 Coil connection body 25, 27 Pull-out part 29 Overhang | projection part 31 Core material 33,33A, 33B Mold | die 34,34A, 34B Cavity 35 Upper mold | type 37 Lower mold | type

Claims (5)

Forming a coil body in which a wire is spirally wound;
A first mold forming a half of a generally barrel-shaped cavity having a rectangular cross-sectional shape perpendicular to the central axis, and a second mold forming the other half of the cavity , arranged opposite to each other in the direction of the press The coil body is placed in a molding die consisting of: and the axial direction of the coil body coincides with the pressing direction , the coil body is pressed in the axial direction by the molding die, and the outer shape of the coil body is shaped cross section perpendicular to the central axis is substantially barrel is rectangular, by bisecting the coil of one of the molded at the center thereof, and characterized in that to create two coils of modified cross-section A method of manufacturing a modified cross-section coil. In the manufacturing method of the irregular cross-section coil according to claim 1,
Manufacturing method of the first and modified cross coil, characterized in that the molded stepwise the coil body by a plurality of times of press forming of the second mold. In the manufacturing method of the irregular cross-section coil according to claim 1 or 2,
A method of manufacturing a deformed cross-section coil, wherein in the step of performing press forming, the first and second dies are simultaneously driven in directions close to each other to perform press forming. In the manufacturing method of the irregular cross-section coil according to any one of claims 1 to 3,
In the step of forming the coil body, the wire is a series of wires, and a method for producing a modified cross-section coil. In the manufacturing method of the irregular cross-section coil according to any one of claims 1 to 4,
In the step of forming the coil body, the wire has a constant cross-sectional shape.

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