JP2015073357A - Molding device and molding method of stator assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve accuracy of resin molding without cutting.SOLUTION: A molding device of a stator assembly applies to a stator assembly comprising a wound stator core 1 and an inner frame 8 covering one end of a coil protruding from the stator core 1 in an axial direction. The molding device has a center post 7 fitted to an inner peripheral surface of the stator core 1. The inner frame 8 has an opening 9 formed on an upper side of one side of the coil. The molding device injects resin into an inner side of the inner frame 8 from the opening 9 when the inner frame 8 covers one end of the coil and an outer peripheral part of the center post 7. Thus resin is fed to the periphery of the coil with a shape and dimension specified by the inner frame 8 without spreading to an outer side of the inner frame 8.

Description

  The present invention relates to fixing of a coil by a resin mold to a stator of a rotating electrical machine.

  A stator coil of a rotating electrical machine is formed by winding a coil around a stator core, and then fixing the coil to the stator core by resin molding using a mold.

  Patent Document 1 proposes such a resin mold forming apparatus. The resin mold forming apparatus includes a mold composed of an upper mold and a lower mold. The steer core that has finished winding is disposed in the recess of the lower mold with one end face facing up. A center post penetrating the stator core is provided at the center of the recess. The center post forms part of the lower mold. The end portion of the coil protruding in the axial direction from one end face of the stator core protrudes above the recess. The upper die is configured to cover the center post and the protruding portion of the coil with a slight gap in contact with the lower die from above.

  A resin injection port is formed in the upper die so as to face the center axis of the center post. The resin injected from the injection port in the state where the upper mold and the lower mold are in contact diffuses in the radial direction through the gap between the upper mold and the center post, and between the end of the coil and the end face of the stator core. Filled.

  In this resin molding apparatus, the resin injected from the injection port is diffused in the radial direction. At this time, the resin is deposited on the end face of the center post that becomes the passage of the resin. Therefore, after the resin is sufficiently filled between the end portion of the coil and the end surface of the stator core, it is necessary to remove the resin deposited on the end surface of the center post. For this purpose, the upper die is provided with a ring-shaped protrusion that protrudes downward in the vicinity of the outer periphery of the center post. The resin diffused in the radial direction from the inlet will reduce the thickness between the projection and the center post. After the injection of the resin is completed, an upward force is applied to the resin deposited on the center post with a pin penetrating the center post, so that the resin pressed against the ring-shaped protrusion is broken into a circle by the protrusion. As a result, the resin deposited on the center post is separated from the resin filled between the end of the coil and the end face of the stator core and removed.

JP 2008-172928 A

  In this resin mold molding apparatus, the ring-shaped protrusion is positioned substantially above the inner peripheral surface of the stator core. That is, the most resin breakage that removes the resin on the center post is performed at this position. However, this rupture is due to the pressing of the ring-shaped protrusion, and it is inevitable that irregularities in the radial direction are generated on the actually generated fracture surface. Therefore, in order to ensure the dimensional accuracy of the stator assembly, it is necessary to cut the broken portion of the resin again.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a stator assembly molding apparatus that can obtain a high resin molding accuracy without requiring a cutting process, in order to solve the above problems of the conventional resin mold molding apparatus.

  In order to achieve the above object, the present invention is applied to a stator assembly molding apparatus in which a stator core wound with a coil is housed in an inner frame. The molding apparatus includes a center post that fits to the inner peripheral surface of the stator core. The inner frame is formed with an opening facing one end of a coil protruding in the axial direction from the stator core. The molding apparatus is configured to inject resin from the opening into the inner frame with the inner frame covering one end of the coil and the outer periphery of the center post.

  The resin injected from the opening diffuses around the coil via a gap between one end of the coil and the inner frame, and fixes the coil to the stator core. Since the resin is directly injected into the fixed portion between the coil and the stator core, the resin does not diffuse to unnecessary portions, and the resin cutting after shaping is not necessary. In addition, since the resin is not broken by pressing the ring-shaped protrusion, the structure of the mold is simplified.

It is a principal part longitudinal cross-sectional view of the shaping | molding apparatus of the stator assembly by embodiment of this invention. 1 is a perspective view of an inner frame according to an embodiment of the present invention. FIG. 3 is an enlarged longitudinal sectional view of a main part of the inner frame, corresponding to the AA section of FIG. 2. It is an enlarged longitudinal cross-sectional view of the inner frame main part which shows arrangement | positioning of the core for oil path formation. It is an expanded longitudinal cross-sectional view of the inner frame principal part which shows the formed oil path.

  Referring to FIG. 1, a stator assembly molding apparatus is applied to a cylindrical stator core 1 in which a coil is wound. The coil is wound around a slot in the stator core 1 and protrudes at both ends on both sides of the stator core 1 in the axial direction. An inner frame 8 is attached to the stator core 1.

  The molding apparatus includes an upper mold 4 and a lower mold 5. The lower die 5 is fitted to the outer periphery of the stator core 1 and includes a columnar center post 7 fitted to the hollow portion at the center of the stator core 1. The lower mold 5 supports the stator core 1 with one end thereof facing upward so that the axial direction overlaps the vertical direction. The lower mold 5 is formed with a space 6 </ b> B that accommodates a coil end protruding downward from the steer core 1.

  The upper die 4 contacts the lower die 5 from above. The upper mold 4 is formed with a recess 4A that fits around the outer periphery of the stator core 1. The recess 4 </ b> A includes a space for accommodating a coil end protruding upward from the stator core 1 and a tip of the center post 7.

  The stator core 1 is arranged in a molding apparatus in a state in which a plurality of coils are wound around a slot and an inner frame 8 that covers an outer periphery of the stator core 1 and a coil end protruding upward from the stator core 1 is mounted.

  Referring to FIG. 2, the inner frame 8 is formed in a cylindrical shape having an end face 8 </ b> A at one end so as to cover one end of the coil and the side surface of the stator core 1. An opening 8B is formed at the center of the end face 8A. In the end face 8A, openings 9 are formed at equal angular intervals at positions corresponding to the coil ends.

  Referring to FIG. 3, the inner frame 8 includes a space 6 </ b> A that fits on the outer periphery of the stator core 1 and accommodates a coil end portion that protrudes upward from the stator core 1. In the inner frame 8. A link-like protrusion 12 is formed in a downward direction to bring the space 6A into a sealed state by contacting the center post 7. The opening 9 is formed at a position facing the space 6A.

  Referring to FIG. 1 again, the upper mold 4 is formed with a resin supply passage 2 for supplying resin to the opening 9 of the inner frame 8. Resin is supplied to the resin supply passage 2 from a resin supply device (not shown). The resin supplied to the resin supply passage 2 is supplied from the opening 9 to the space 6 </ b> A in the inner frame 8.

  The resin supplied to the space 6 </ b> A fills the space between adjacent coil ends, and also fills the space 6 </ b> B formed in the lower mold 5 through the slot of the stator core 1. In this way, the coils are fixed to the stator core 1 by filling the spaces 6A and 6B and the slots connecting the spaces 6A and 6B with the resin.

  The resin injected into the space 6 </ b> A is prevented from diffusing from the space 6 </ b> A toward the center by the ring-shaped protrusion 12 in contact with the center post 7. Therefore, no resin is present on the center post 7 at the time when the injection of the resin is completed and the upper mold 4 and the lower mold 5 are separated. In other words, no extra resin remains around the stator core 1 as in the prior art. Therefore, after removing the upper mold 4 and the lower mold 5, it is necessary to break the excess resin remaining on the center post 7 by pressing force, and it is necessary to cut the resin remaining around the center post 7 after the break. Absent. Therefore, it is not necessary for the molding apparatus to include a mechanism for breaking. In addition, labor for cutting can be reduced. Further, the entire amount of resin injected into the inner frame 8 from the opening 9 can be used for fixing the coil without leaving any excess. As a result, the coil can be fixed to the stator core 1 with resin at low cost and with high accuracy.

  As described above, the stator assembly is completed by being fixed to the stator core 1 of the coil by injecting resin from the opening 9 into the inner frame 8.

  When the stator assembly is incorporated into a rotating electrical machine such as an electric motor, the stator assembly is fixed to the housing of the rotating electrical machine via the inner frame 8. The opening 9 formed at a position corresponding to the coil end of the inner frame 8 functions as a heat radiating hole for each coil in the operation of the rotating electrical machine. During operation of the rotating electrical machine, the coil generates heat by forming a magnetic field. The heat radiating hole radiates this heat to prevent the coil from being heated. That is, according to this embodiment, it is possible to efficiently fix the coil to the steer core 1 with the resin using the inner frame 8 that is a component of the completed rotating electrical machine.

  By the way, when the inner frame 8 is mounted on the stator core 1, the end portions of the coils are arranged in the inner frame 8 at equal angular intervals. In this state, it is also preferable to form an oil passage 11 as shown in FIG. 5 using a space between adjacent coils. In that case, the oil inlet 13 is formed on the end face of the inner frame 8 at a position corresponding to the oil passage 11 separately from the opening 9. The oil inlet 13 and the oil passage 11 function as a cooling oil supply oil passage for cooling the stator assembly during operation of the rotating electrical machine.

  Referring to FIG. 4, in order to form the oil passage 11, in this embodiment, the core 10 is provided in the inner frame 8 when the inner frame 8 is attached to the stator core 1 prior to resin injection. Since the oil passage 11 is bent in the radial direction in the middle, the core 10 is arranged in each space between adjacent coils in the space 6A of the inner frame 8 in a state of being divided into elements 10A and 10B. .

  After the resin injection by the molding apparatus is completed and the upper die 4 and the lower die 5 including the center post 7 are removed, the element 10A is pulled upward from the middle oil port, and the element 10B is a resin filled in the space 6A. It is pulled out inward in the radial direction from the inner peripheral surface. Thereby, the oil path 11 is formed in the space 6A filled with the resin.

  Thus, by arranging the core 10 in the inner frame 8, the oil passage 11 for the lubricating oil can be formed when the resin is injected. Thereby, after molding of the stator assembly, a processing operation for forming the oil passage 11 again becomes unnecessary, and the amount of resin used can be reduced.

  As described above, the present invention has been described through specific embodiments. However, the present invention is not limited to the above embodiments. Those skilled in the art can make various modifications or changes to these embodiments within the scope of the claims.

1 Stair Core 2 Resin Supply Passage 4 Upper Die 4A Recess 5 Lower Die 6A, 6B Space 7 Center Post 8 Inner Frame 8A End Face 8B Opening 9 Opening 10 Core 10A, 10B Element 11 Oil Path 12 Ring-shaped Projection 12 Projection 13 Oil Filling Port

Claims (6)

A stator assembly molding apparatus in which a stator core wound with a coil is housed in an inner frame,
A center post that fits to the inner peripheral surface of the stator core;
The inner frame covers one end of the coil protruding in the axial direction from the stator core and the outer periphery of the center post,
A stator assembly molding apparatus, wherein a resin is injected into an inner frame from an opening formed in an inner frame facing one end of the coil.   The stator assembly molding apparatus according to claim 1, wherein a plurality of coils are wound around the stator core, and the opening is formed at a position facing one end of each of the coils.   3. The stator assembly molding apparatus according to claim 1, wherein the inner frame includes a ring-shaped protrusion that prevents the resin injected from the opening from diffusing toward the center by contacting the center post. 4. .   4. The stator assembly molding apparatus according to claim 1, wherein the opening serves also as a heat radiating hole for generating heat due to a magnetic field formed by the coil when the coil is energized. 5.   The stator according to any one of claims 1 to 4, further comprising a core supported by the inner frame so as to form an oil passage from an outer side of the inner frame toward an inner peripheral surface of the stator core in a resin filling portion between adjacent coils. Assembly molding equipment. A stator assembly molding method in which a stator core wound with a coil is housed in an inner frame,
A center post is fitted to the inner peripheral surface of the stator core,
The inner frame covers one end of the coil protruding in the axial direction from the stator core and the outer periphery of the center post,
A method for molding a stator assembly, wherein a resin is injected into an inner frame from an opening formed in an inner frame facing one end of the coil.

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