JP2005080488A - Method and equipment for extending and molding stator coil end of rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and equipment for extending and moulding a stator coil end of a rotary electric machine in which the drop of a field coil from an embossing die when it is extended and molded is resolved by shortening the loop length and downsizing a coil end portion. <P>SOLUTION: In a manufacturing process of the stator of the rotary electric machine, when extending and moulding in which a coil end portion 20 that straddles over slots of a stator core A is bent in the radial outward direction of the stator core by pressure and molded by an embossing die 30, the movement of the coil end portion in stator core end surface direction is regulated by a flange 32 provided on a pressing surface 31 of the embossing die, thereby preventing the drop from the die due to deviation on the pressing surface. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to the manufacture of rotating electrical machines such as motors, generators, and motor generators, and more particularly to expansion molding of a coil end portion of a field coil after being inserted into a stator core in the manufacture of a stator of the rotating electrical machine.

  In the process of manufacturing a rotating electrical machine such as a three-phase motor with distributed winding, a U-phase, V-phase, and W-phase formed by winding a wire (magnet wire) with a winding machine separately in a slot of a stator core that has been assembled in advance. While the field coils are sequentially inserted using an insertion machine (inserter), the coil end portion where the inserted U-phase coil straddles the slots at both ends of the stator core is the V-phase coil to be inserted next. The overlapping portion is pushed outward in the radial direction of the stator core to secure a space for the coil end portion of the V-phase coil, and after inserting the V-phase coil, the W-phase coil end portion is inserted last. Similarly, the range overlapping with the other coil is also expanded outward in the radial direction, and so-called intermediate forming is performed to secure a space for the coil end portion of the W-phase coil. FIG. 10 schematically shows the shape of the coil end portion that has been expanded by intermediate forming. As shown in the figure, the U-phase coil end portion 20u inserted first is largely bent in the axial direction along the cuff portion 11 of the slot cell mounted in the slot of the stator core A, and then inserted into the V-phase. The coil end portion 20v is bent along the cuff portion 11 and the U-phase coil end portion 20u, and the W-phase coil end portion 20w inserted last is positioned in the opened space. In this intermediate molding, a method called bullet molding is generally used in which a shell-shaped molding machine (former) is inserted into the inner peripheral space of the stator core to push the coil end portion.

Recently, from the viewpoint of environmental conservation, hybrid vehicles and electric vehicles that use rotating electric machines for driving, power generation, regenerative braking, etc., are being put into practical use from the viewpoint of environmental conservation, and in particular, such onboard rotation In an electric machine (a three-phase brushless DC motor is generally used), there is a significant demand for further miniaturization and higher output. In order to meet such a demand, it is necessary to reduce the coil end portion in addition to increasing the occupation ratio in the slot of the coil of the rotating electrical machine (increasing the number of coil wires). Thus, in order to reduce the size of the coil end portion, the loop length of the coil must be made as short as possible with respect to the axial length of the slot. Thus, in a motor with a specification in which the coil loop length is shortened by reducing the coil loop length relative to the axial length of the stator core, coil return (spring back) during molding is strong, and friction between coils is also strong. Insulation is easily damaged. For this reason, the method of expansion molding which can extrude a coil end part more radially outside and has little friction between coils is taken. As a technique for disclosing such extended molding, there is a technique described in Patent Document 1.
JP 11-27889 A

  However, in the case of this extension molding, in the coil end portion reduced in size, as shown in the step of the extension molding procedure in FIG. As it is deformed in the radial direction, the coil easily shifts in the end surface direction, protects the cuff portion of the slot cell, and supports the support core D, which is a jig for pressing the both end surfaces of the stator core, and the pressing die Ca of the expansion former C. There is a possibility that part of B is bitten and the insulation of the coil is damaged.

  Further, since the coil loop length is short, the rising portion of the coil from the stator core slot is difficult to lie down on the core end face side. Therefore, when the last W-phase coil is inserted, the U-phase coil and V-phase that are inserted earlier are inserted. The rising part of the coil hits the W-phase coil and becomes resistance to insertion, or conversely, excessive force is applied to the W-phase coil, which may cause the coil wire (magnet wire) to stretch or cause insulation failure. was there.

  The present invention has been devised in view of the circumstances as described above, and it is a main object of the present invention to prevent the coil from being detached from the expansion molding machine during the expansion molding of the coil end portion of the stator in the manufacture of a rotating electrical machine. And Next, another object of the present invention is to prevent elongation and damage of a magnet wire that constitutes a coil to be subsequently inserted during expansion molding of a coil end.

  In order to achieve the above object, the coil end expansion molding method of the present invention provides a coil end in which a coil inserted across different slots of a stator core straddles between slots at both axial ends of the stator core in the manufacturing process of a stator of a rotating electrical machine. The coil end portion is restricted from moving in the direction of the stator core end surface that is disengaged from the pressing surface of the pressing die during expansion molding in which the portion is pushed and molded by the pressing die to the outside in the radial direction of the stator core.

  In the above configuration, the coil is composed of a plurality of coils inserted at different times and straddling different slots of the stator core, and at least during expansion molding of the coil end portion of the coil inserted later, The rising portion of the coil from the previously inserted slot can be laid down and deformed in the direction of the end face of the stator core. More specifically, the coil is kept at a predetermined creepage distance by interposing the insulating material with respect to both end surfaces of the stator core at the coil end portion by an insulating material arranged in advance so as to cover the slot and its periphery. The expansion of the stator core is restricted, and the restriction of the movement in the direction of the stator core end face is to prevent the coil end part from falling off to the stator core end face side.

  Next, in the coil end expansion molding method of the present invention, in the manufacturing process of the stator of the rotating electrical machine, the coil end portion in which the coil inserted across the different slots of the stator core straddles between the slots at both axial ends of the stator core After the expansion process in the previous stage of pressing and bending outward in the radial direction of the stator core, a plurality of coils inserted across different slots of the stator core are provided with a coil end portion straddling the slots at both ends in the axial direction of the stator core. At the time of expansion molding at a later stage of pressing and bending outward in the radial direction, at least the rising portion of the coil from the previously inserted slot is laid down and deformed toward the end face direction of the stator core.

  In any of the above configurations, the rotating electrical machine is a three-phase distributed winding motor, and the expansion molding can be performed on coils other than the coil of the phase finally inserted into the slot.

  Next, in the coil end expansion molding apparatus of the present invention, in the manufacturing process of the stator of the rotating electrical machine, the coil inserted across different slots of the stator core pushes the coil end portion straddling the slots at both ends in the axial direction of the stator core. In an expansion molding apparatus that press-bends and molds radially outward of the stator core with a mold, a flange that restricts the movement of the coil end portion in the direction of the stator core end surface that is detached from the pressing surface of the pressing mold is provided at the tip of the pressing mold. It is characterized by.

  In the above configuration, more specifically, the stator core includes an insulating material that is arranged in advance so as to cover the slot and the periphery thereof, and the coil has the insulating material at both ends of the stator core at a coil end portion. The flange is formed in a hook-like shape along the end surface of the insulating material of the push die in order to prevent the coil end portion from falling off to the end surface side of the stator core, while maintaining a predetermined creepage distance. It can be set as the structure provided in. The pressing die includes a first pressing portion that presses a portion excluding a rising portion of the coil from the slot, and a second pressing portion that presses the rising portion of the coil from the slot. It can also be set as the structure provided in the 1st press part, and the said 2nd press part provided in the both sides which pinch | interpose the said 1st press part. In addition, the second pressing portion is located at a position retracted from the first pressing portion and has a pressing surface inclined with respect to the pressing surface of the first pressing portion, and a rising portion of the coil from the slot It is desirable to lay them in the direction of the end face of the stator core. When the rotating electric machine is an n-phase distributed winding motor having an arbitrary number of phases n, the inclined pressing surface is from the slot of the n-1 phase coil inserted into the slots of the stator core in phase order. It is assumed that the rising part is pressed.

  In the configuration according to the first aspect, when the coil end portion is formed by extending the coil loop length shorter than the axial length of the core, the coil end portion shifts in a direction approaching both end faces of the core as the forming proceeds. In contrast to the behavior, the shift causes the coil end portion to be scooped up without coming off the pressing surface of the pressing die, and the coil end portion is subjected to expansion molding. Therefore, the inner peripheral side of the coil end part is not removed from the pressing die during the expansion molding, and the supporter (jig) holding the stator core end surface during the molding and the pressing die is not rubbed against each other. As a result, the insulation of the coil is not impaired.

  Next, in the configuration of the second aspect, when the coil inserted later is expanded, the rising portion from the core of the previously inserted coil is additionally laid down, so that it is inserted later. Further, the rising portion from the core of the coil inserted into another adjacent slot does not overlap with the coil end portion of the previously inserted coil. Accordingly, the insertion resistance of the coil to be inserted later does not increase, and the insertion thrust does not increase, so that the magnet wire constituting the coil can be prevented from being stretched or damaged.

  Moreover, in the structure of Claim 3, when a stator core is normally equipped with the insulating material with which it is mounted | worn, the coil end part falls to the stator core end surface side by the press to the axial direction of the stator core of a coil end part Can be prevented.

  Next, in the configuration of the fourth aspect, when the coil inserted later is expanded, the rising portion from the core of the previously inserted coil is additionally laid down, so that it is inserted later. Further, the rising portion from the core of the coil inserted into another adjacent slot does not overlap with the coil end portion of the previously inserted coil. Accordingly, the insertion resistance of the coil to be inserted later does not increase, and the insertion thrust does not increase, so that the magnet wire constituting the coil can be prevented from being stretched or damaged.

  Moreover, in the structure of Claim 5, said each effect can be achieved in the process of manufacturing a three-phase distributed winding motor.

  Next, in the configuration according to claim 6, the direction in which the coil end portion approaches the both end surfaces of the core as the forming progresses at the time of expansion forming of the coil end portion in which the loop length of the coil is shorter than the axial length of the core. In contrast to this, the shift can prevent the coil end portion from coming off the pressing surface of the pressing die by this displacement. Therefore, the inner peripheral side of the coil end portion, in particular, does not come out of the pressing die during expansion molding and is rubbed with the supporter and does not rub against each other, thereby preventing the insulation of the coil from being impaired. Moreover, such an effect can be achieved only by the peculiarity of the pressing surface shape that does not require any special additional device or operation.

  Moreover, in the structure of Claim 7, when a stator core is equipped with the insulating material with which the stator core is normally mounted | worn, the drop-off to the stator core end surface side of the coil end part inner peripheral side by the press to the axial direction of the stator core of a coil end part Can be prevented.

  Further, in the configuration according to claim 8, molding that presses a portion excluding the rising portion from the coil slot by one operation while preventing the portion from falling off to the stator core end surface side, and the rising portion from the coil slot Can be formed.

  Further, in the configuration according to claim 9, by a single operation, a portion excluding the rising portion from the coil slot is pressed while preventing the coil core from falling off to the end face of the stator core, and then from the coil slot. In order to prepare the next rising portion for insertion of the next coil, it is possible to perform the molding in which it is laid down in the direction of the end face of the stator core.

  Moreover, in the structure of Claim 10, each said effect can be achieved in the process of manufacturing the distributed winding motor of arbitrary phase number n.

  In the present invention, the movement of the coil end portion in the direction away from the pressing die, that is, the movement restriction in the direction in which the inner peripheral side of the coil end portion approaches the end face of the stator core is limited to the expansion molding of the coil first inserted in the stator core slot. It is desirable to apply the expansion molding of the rising portion from the slot in combination with the restriction of the movement of the coil inserted thereafter in the direction away from the pressing mold at the time of expansion molding of the coil inserted thereafter. . For this purpose, as the apparatus of the present invention, a plurality of stamping dies corresponding to the number of phases having different shapes for expansion molding are prepared, and the coil end portions of the respective phases are inserted according to the insertion stage of the coil of each phase. Expansion molding is performed in stages.

  The present invention will be described by taking as an example a case where coil end expansion molding of a three-phase coil with distributed winding is performed. FIG. 1 schematically shows the relationship between a stator core (hereinafter abbreviated as “core” in the description of the embodiment) and a coil as viewed in the axial direction of the core. The assembly of the coil B to the core A in this embodiment is performed by assembling the 12-pole field coils of U, V, and W phases to the core having 72 slots 10 and the U-phase 12-pole coil. The pole of one pole (only three poles are indicated by a solid line in the figure) is positioned so as to straddle the two slots 10 jumping the middle four slots, and the next pole connected to the coil of this pole by a crossover Are positioned so as to straddle the slot 10 adjacent to one side of the two slots and the two slots jumped with the middle four, and the coils of each pole are positioned in the same positional relationship. One phase (12 poles) is inserted into the slot by one operation using an inserter. At the stage when the insertion is completed, the number of pressing dies arranged in the expansion molding apparatus (hereinafter referred to as a former in the description of the embodiment) is 12, and the U-phase coil ends according to the present invention are applied to all the coil ends. The part is expanded. Next, the V-phase coil (only three poles are indicated by a broken line in the figure) is shifted by 2 slots with respect to the slot 10 in which the U-phase coil is inserted, and is similarly operated once by using the inserter. Insert into the slot. At the stage when this insertion is completed, the V-phase coil is expanded and formed in the same manner for each coil end portion. Then, a W-phase coil (only three poles are indicated by a two-dot chain line) is inserted into the last remaining slot 10.

  Next, the former according to the embodiment is shown in a partial axial cross section in FIG. 2 together with the horizontally mounted core. This cross section shows only the cross section corresponding to the coil end portion of one pole, and the same arrangement configuration is also taken for the other 11 pole coil end portions separated by 30 ° in the circumferential direction of the core. . This device has a configuration in which two push dies 30 are mounted and supported symmetrically at the tip of a radially extending mechanism of a former C, which is not shown in the figure, which can be inserted into the inner peripheral hollow portion of the core A. . The illustrated pressing die 30 is for expanding the coil end portion 20 of the U-phase coil that is first inserted into the slot of the core A. As shown in FIG. In addition, it is configured as a bowl-like block as a whole having a horizontal portion at the upper end of the plate-like vertical portion, and the outer surface of the vertical portion facing the inner peripheral surface of the core A constitutes the pressing surface 31. The pressing surface 31 is a cylindrical surface having an intermediate curvature between the inner peripheral surface and the outer peripheral surface of the core A, and the portion where the pressing surface 31 is connected to both side surfaces 33 is appropriately rounded. And according to the feature of the present invention, the flange 32 is integrally formed at the bottom of the pressing surface 31 so as to project. The flange 32 is formed in a bowl shape over the entire width of the pressing surface 31, and both ends thereof are connected to both side surfaces 33 with appropriate roundness.

  Referring to FIG. 2, coil B includes both end surfaces (horizontal mounting) of coil A at coil end portion 20 by slot cell 11 that constitutes an insulating material previously disposed so as to cover the slot of core A and its periphery. The upper and lower surfaces in the state are expanded by maintaining a predetermined creepage distance by interposing a cuff portion (acting as a spacing member) 11a of the slot cell 11 and moving in the direction of the core end surface. The regulation prevents the laminated steel plate at the end of the stator core from being caught by the coil, prevents the coil from coming into contact with the corners of the stator core and scratches it, and causes the slot cell to fall due to the coil falling down when expanding the coil. In order to prevent the cuff portion 11a from being crushed, there is a coil end portion in the bottom portion of the comb teeth of the supporter D as a jig applied to both end faces of the stator core. It is intended to prevent the side is bitten. Therefore, this bowl-shaped ridge 32 of the pressing die 30 extends along the upper and lower surfaces of the supporter D by pushing the pressing die 30 in the core radial direction (FIG. 2 shows a state where the pressing die 30 has already been pushed). The spacer 5 that adjusts the distance between the flanges 32 of the upper and lower pressing molds 30 can be adjusted by interposing it in the pressing mold support portion. Since the thickness of the support D is slightly thicker than the height of the cuff part 11a of the slot cell 11, this distance moves along the upper and lower edges of the cuff part 11a of the slot cell 11 while maintaining a slight space. It becomes distance to do.

  Next, the work process of coil end expansion molding by the former will be described. With reference to the process explanatory diagram of FIG. 4, initially, when the coil B is inserted into the slot of the core A, the pressing die 30 of the former C is located radially inward from the inner periphery of the core A. When the expansion work is started from this state, as shown in the middle part of FIG. 4, first, the flange 32 of the pressing die 30 starts to contact the supporter D, and the coil end is brought into contact with the coil end portion 20 of the pressing surface 31. Radial compression of part 20 (indicated by the arrow in the figure) begins to occur. When the extrusion further proceeds and the radial movement of the entire coil end portion 20 starts, the coil end portion 20 starts moving in the axial direction of the core A, and eventually the coil end portion 20 as shown in the lower stage of FIG. The inner peripheral side of the ring is in contact with the flange 32. From this state, the movement in the axial direction is restricted by the flange 32, so that the phenomenon that the inner peripheral side of the coil end portion is caught between the pressing die 30 and the supporter D is avoided. Thus, when the coil end portion 20 is pushed and bent to a predetermined position by extrusion of the pressing die 30, the pressing die 30 is retracted to complete the initial U-phase coil end portion expansion molding operation.

  FIGS. 5A and 5B are perspective views showing states before and after the coil end portion expansion molding of the U-phase coil. As shown in the upper part of FIG. 5, the coil end portion 20 is positioned so as to cover the slots 10v and 10w other than the coil insertion slot before the expansion molding. In the illustrated example, one pole of the U-phase coil is inserted across the four slots 11v and 11w for inserting the V-phase and W-phase coils. A state where two pole coils are inserted into adjacent slots is shown. On the other hand, in the state after the expansion molding shown in the lower part of FIG. 5, the coil end portion 20 of the U-phase coil is pushed away radially outward, thereby inserting the V-phase and W-phase coils. Slots 11v and 11w are opened. As a result, the coils of these phases can be smoothly inserted into the slots.

  By the way, even when the above-described expansion molding is performed, when the loop length of the coil is made as short as possible, the bending of the magnet wire at the rising portion 21 from the slot is gentle as shown in the lower part of FIG. (Curvature is small). Such gentle bending causes an increase in insertion resistance when the next V-phase or W-phase coil is inserted by the inserter. This increase in insertion resistance leads to elongation and damage of the magnet wire when the coil is inserted.

  Therefore, in order to cope with such a situation, in accordance with the feature of the present invention, a second shape having a shape different from that of the first pressing die 30 is used for the expansion molding of the coil end portion of the V-phase coil to be inserted next. A stamping die 40 is prepared. FIG. 6 is a perspective view showing the shape of the second pressing die 40. The pressing die 40 is configured in a block shape having substantially the same width and height as the first pressing die 30, but the pressing surface 41 that presses the V-phase coil end portion is mainly in the center of the coil end. The pressing surfaces 44 which are narrow in order to ensure the radial pushing stroke of the portion and are slightly retreated from the pressing surface 41 are formed on both sides of the pressing surface 41 of the coil end portion. The pressing surfaces 44 on both sides are provided mainly to cause deformation that causes the rising portion of the coil end portion to lie in the direction of the end surface of the core. In the case of this pressing die 40, the first pressing surface 41 is not a partial cylindrical surface because it has a narrow width, and is a flat surface. The point that the flange 42 is formed at the lower end of the pressing surface 41 is the same as the first pressing die 30. The second pressing surface 44 is a plane parallel to the first pressing surface 41 as a whole, but the portion where the lower end of the pressing surface 44 is connected to the lower surface is cut off obliquely to form the inclined surface 45. In addition, the lower portion of the portion where the pressing surface 44 and both side surfaces 43 are connected is also cut off obliquely. With such a surface configuration, the first pressing surface 41 functions as a surface that presses the coil end portion, and the inclined surface 45 of the second pressing surface 44 mainly presses in the direction in which the rising portion from the slot of the coil end portion lies. It functions as a surface to perform.

  The second die 40 is attached to the former C in the same manner as the first die 30 is attached to the former. Next, the state shown in the upper part of FIG. 7 and the left side of FIG. 8 shows the state at the start of expansion molding similar to FIG. Since the expansion molding operation by the pressing die 40 is the same as the previous case, the intermediate process is omitted, and the state after molding is shown in the lower stage of FIG. 7 and the right side of FIG. At the time of molding, the inclined surface 45 of the second pressing surface 44 presses the rising portion 21 from the core of the coil end portion, and therefore, referring to the lower part of FIG. It can be seen that the upper and lower portions of the slot 10 are laid in the direction along the end surface of the core A.

  FIG. 9 shows the state after the expansion molding of the V-phase coil. In the state after the expansion molding shown in FIG. 9, the coil end portions 20u, 20v of the U-phase and V-phase coils are pushed outward in the radial direction, and the rising portions 21u, 21v is also laid in the direction of the end face of the core A. Thereby, the two slots 10w for inserting the W-phase coils are opened. As a result, the last W-phase coil can be smoothly inserted into the slot 10w without interfering with the previously inserted U-phase and V-phase coils.

  As described above in detail, according to this embodiment, at the time of expansion molding of the U-phase coil end portion, this portion is bitten into the supporter D by scooping up the inner end side of the coil end portion by the flange 32 of the pressing die 30. The coil end portion is extruded in the radial direction while being blocked, and at the time of expansion molding of the V-phase coil end portion, the U-phase molding is performed by the first pressing surface 41 of the second pressing die 40 and the flange 42 associated therewith. Extrusion similar to that at the time is performed, and the laying deformation of the rising portion from the slot of the previously formed U-phase coil is simultaneously performed by pressing by the inclined surface 45. Therefore, by such an action, the insertion slot of the W-phase coil that is finally inserted into the slot is sufficiently opened, and the insertion resistance during insertion by the inserter is reduced. Thus, according to this embodiment, in particular, the coil occupancy in the slot is increased for higher output, and the coil loop length is made shorter than the axial length of the core for reducing the coil end portion. Engagement of the coil with the supporter D, expansion of the magnet wire, and generation of flaws accompanying expansion molding in the coil can be reliably prevented.

  The present invention is widely applicable to the manufacture of a stator for a general multi-phase rotating electrical machine. For example, the coil end of a U-phase coil of a three-phase coil in the manufacture of a three-phase induction motor or generator stator. And applicable to expansion molding of the coil end of the V-phase coil.

It is a schematic diagram which shows the coil arrangement | positioning of the distributed winding 3 phase motor of an Example. It is a fragmentary sectional view which shows the expansion former of an Example with a stator core seeing in an axial direction. It is a perspective view which shows the pressing die for U-phase coil expansion molding of an Example. It is process explanatory drawing which shows the U-phase coil expansion molding process by the method of an Example in a side view in steps. It is a fragmentary perspective view of the stator core which compares and shows the state before and behind the U-phase coil expansion by the method of an Example. It is a perspective view which shows the V-phase coil expansion shaping | molding die of an Example. It is process explanatory drawing which shows the V phase coil expansion molding process by the method of an Example in a side view in steps. It is process explanatory drawing which shows the V phase coil expansion molding process by the method of an Example in planar view in steps. It is a fragmentary perspective view of the stator core which shows the state after V phase coil expansion by the method of an Example. It is process explanatory drawing which shows the expansion molding process of the conventional U-phase coil in a side view in steps. It is sectional drawing which shows typically the stator core of a general 3 phase rotary electric machine.

Explanation of symbols

A Stator core B Coil C Former (expansion molding device)
10 slots 11 slot cells (insulating material)
11a cuff part 20 coil end part 21 rising part 22 part excluding rising part 30 first pressing die 31 pressing surface 32, 42 ４０ 40 second pressing die 41 first pressing part 44 second pressing part 45 inclined surface (Second pressing surface)

Claims (10)

In the manufacturing process of a stator of a rotating electrical machine, an extension in which a coil inserted across different slots of the stator core is formed by pushing and bending a coil end portion across the slots at both axial ends of the stator core to the outside of the stator core in the radial direction. During molding,
A coil end expansion molding method characterized by restricting movement of a coil end portion in the direction of a stator core end surface that deviates from a pressing surface of the pressing die.   The coil is composed of a plurality of coils inserted across different slots of the stator core at different times, and is inserted at least first in the expansion molding of the coil end portion of the coil inserted later. The coil end expansion molding method according to claim 1, wherein the rising portion of the coil from the slot is laid down and deformed toward the end face direction of the stator core.   The coil is formed by an insulating material that is arranged in advance so as to cover the slot and the periphery thereof, and is expanded and formed at a coil end portion with a predetermined creepage distance with respect to both end surfaces of the stator core by interposing the insulating material. 3. The coil end expansion molding method according to claim 1, wherein the restriction of movement toward the stator core end face direction is to prevent the coil end portion inner peripheral side from falling off to the stator core end face side.   In the manufacturing process of a stator of a rotating electrical machine, an expansion at a stage before a coil end portion in which a coil inserted across different slots of the stator core straddles between the slots at both axial ends of the stator core is formed by pushing and bending outward in the radial direction of the stator core After the molding, a plurality of coils inserted across different slots in the stator core are expanded at a later stage by pressing and bending the coil end portion across the slots at both axial ends of the stator core to the outside in the radial direction of the stator core. A coil end expansion molding method characterized in that at the time of molding, at least a rising portion of a coil from a previously inserted slot is laid down and deformed in the direction of the end face of the stator core.   The coil end extension according to any one of claims 1 to 4, wherein the rotating electrical machine is a three-phase distributed winding motor, and the expansion molding is performed on a coil excluding a coil of a phase finally inserted into a slot. Molding method. In the manufacturing process of a stator of a rotating electrical machine, an extension in which a coil inserted across different slots of the stator core is formed by pushing and bending a coil end portion across the slots at both axial ends of the stator core to the outside of the stator core in the radial direction. In the molding equipment,
A coil end expansion molding apparatus characterized in that a flange for restricting movement of the coil end portion in the direction of the stator core end surface that comes off the pressing surface of the pressing die is provided at the tip of the pressing die.   The stator core includes an insulating material arranged in advance so as to cover the slot and the periphery thereof, and the coil is expanded at a coil end portion with a predetermined creepage distance by interposition of the insulating material with respect to both end surfaces of the stator core. The said flange is formed in a hook shape in a portion along the end surface of the insulating material of the push die so as to prevent the coil end portion from falling off to the end surface side of the stator core. The coil end expansion molding apparatus as described.   The pressing die includes a first pressing portion that presses a portion excluding the rising portion of the coil from the slot, and a second pressing portion that presses the rising portion of the coil from the slot, and the scissors include the first pressing portion. The coil end expansion molding apparatus according to claim 6 or 7, wherein the second pressing part is provided on both sides of the first pressing part.   The second pressing portion is in a position retracted from the first pressing portion and has a pressing surface inclined with respect to the pressing surface of the first pressing portion, and the rising portion of the coil from the slot is used as a stator core. The coil end expansion molding apparatus according to claim 8, wherein the coil end expansion molding apparatus is laid in the direction of the end face.   The rotating electrical machine is an n-phase distributed winding motor having an arbitrary number of phases n, and the inclined pressing surface is a rising portion from a slot of an n-1 phase coil inserted into a slot of a stator core in order of phase. The coil end expansion molding apparatus of Claim 8 which presses.

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