Motor core manufacturing device and motor core manufacturing method

Abstract

A motor core manufacturing device according to the present disclosure comprises a die for holding a motor core including a resin filling portion, a chamber which is formed in the die and which has one end portion that communicates with a resin composition filling path communicating with the resin filling portion, a plunger for conveying a thermosetting resin composition, conveyed into the chamber, toward the resin composition filling path, a heater situated inside the die or inside the die and around the chamber, and an extruder for conveying the resin composition to the chamber while kneading the same, in order to introduce the resin composition into the chamber, wherein the extruder includes: an extrusion conveying path through the interior of which the resin composition is conveyed; a screw which is situated inside the extrusion conveying path to convey the resin composition while kneading the same; and a first temperature regulating mechanism having at least a portion situated inside the screw.

Description

[Technical Field]

[0001] The present disclosure relates to a motor core manufacturing apparatus and a motor core manufacturing method. [Background technology]

[0002] Some rotating electrical machines have permanent magnets attached to a motor core, such as a rotor core. When attaching a permanent magnet to a motor core in this way, a method is known in which the permanent magnet is inserted into a slot provided in the motor core, and then a resin composition is filled around the magnet and cured (see, for example, JP 2013-009453 A).

[0003] Japanese Patent Application Laid-Open Publication No. 2013-009453 describes a method in which, when filling slots in a rotor core with a thermosetting resin composition, resin tablets of a predetermined size taking into account the required filling amount are placed in a pot and heated in the pot to soften and melt the resin before filling. Summary of the Invention [Problem to be solved by the invention]

[0004] In the device described in JP 2013-009453 A, it is common to prepare more resin than the specified fill amount, taking into account product dimensional tolerances, etc., to ensure that the resin to be filled into the slot, such as thermosetting resin, is not insufficient. However, in this case, since thermosetting resin cannot be reused after hardening, if the resin filling area is small due to dimensional tolerances, a lot of resin is wasted. Furthermore, motor cores come in a variety of shapes, and therefore the slot shapes into which magnets are inserted can also vary, so slot shapes are rarely the same across different vehicle models. Therefore, preparing resin tablets of the optimal size for each motor core requires storage space, which increases management costs. There are also problems such as the cumbersome management of various types of resin tablets.

[0005] Furthermore, as the development of rotating electrical machines for driving and generating electricity in electric vehicles accelerates, the size and slot shapes of the rotating electrical machines themselves are becoming more diverse, and the amount of resin used is also increasing, necessitating larger resin tablets. When a large amount of resin is filled, temperature control of the resin tends to become more difficult than when a small amount of resin is used, making temperature unevenness, such as localized overheating or underheating, more likely to occur. When using a thermosetting resin composition, such temperature unevenness can cause variations in the timing of curing, which can ultimately lead to poor filling of the resin composition.

[0006] In view of the above-mentioned problems, the present disclosure aims to provide a motor core manufacturing apparatus and a motor core manufacturing method that can suppress resin composition loss while suppressing poor filling of the resin composition. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, a motor core manufacturing apparatus according to a first aspect of the present disclosure includes a mold for holding a motor core including a resin filling portion, a chamber formed in the mold and having one end connected to a resin composition filling path which is connected to the resin filling portion, a plunger for transporting a thermosetting resin composition transported to the chamber toward the resin composition filling path, a heater disposed within the mold or within the mold and around the chamber, and an extruder for transporting the resin composition to the chamber while kneading it in order to introduce the resin composition into the chamber, wherein the extruder includes an extrusion conveying path through which the resin composition is transported, a screw disposed within the extrusion conveying path for transporting the resin composition while kneading it, and a first temperature control mechanism disposed at least partially inside the screw.

[0008] In the motor core manufacturing apparatus described above, the resin composition to be introduced into the chamber does not need to be preformed into tablets. The amount of resin composition supplied to the chamber can be easily adjusted, thereby reducing resin composition loss. Furthermore, the resin composition conveyed by the screw can be cooled or heated using the first temperature control mechanism. For example, using the first temperature control mechanism to cool the resin composition can suppress temperature increases due to shear heat generated during conveyance. This can suppress unintended curing reactions during conveyance of the resin composition, thereby avoiding poor filling of the resin composition. Furthermore, using the first temperature control mechanism to heat the resin composition can assist in rapid temperature increases in the extruder. Furthermore, shear heat generated during conveyance of the resin composition often occurs locally, potentially causing temperature unevenness. Heating the resin composition using the first temperature control mechanism can also be expected to suppress this temperature unevenness.

[0009] A motor core manufacturing apparatus according to a second aspect of the present disclosure is a motor core manufacturing apparatus according to the first aspect of the present disclosure, wherein the extruder further includes a second temperature control mechanism arranged in the extrusion conveying path surrounding a portion of the screw.

[0010] In the motor core manufacturing apparatus described above, in addition to the first temperature control mechanism disposed inside the screw, a second temperature control mechanism disposed in the extrusion conveying path is included, so that the resin composition conveyed in the extrusion conveying path can be cooled or heated from both the inside and outside, thereby more reliably controlling the temperature of the resin composition during conveying.

[0011] A motor core manufacturing apparatus according to a third aspect of the present disclosure is a motor core manufacturing apparatus according to the first or second aspect of the present disclosure, wherein the first temperature control mechanism includes an inlet channel having a heat medium supply port at one end and extending from the base end side of the screw along the central axis of the screw, and an outlet channel having one end connected to the other end of the inlet channel and extending toward the base end side of the screw.

[0012] In the motor core manufacturing apparatus described above, a passage is formed inside the screw through which a heat medium can pass, making it possible to cool or heat the screw and the resin composition around the screw by supplying the heat medium inside the screw.

[0013] A motor core manufacturing apparatus according to a fourth aspect of the present disclosure is the motor core manufacturing apparatus according to the third aspect of the present disclosure, wherein the heat medium used in the first temperature adjustment mechanism is a gas.

[0014] In the motor core manufacturing apparatus as described above, the first temperature adjustment mechanism uses a gas as the heat medium, which makes it easier to handle than when a liquid heat medium is used.

[0015] A motor core manufacturing apparatus according to a fifth aspect of the present disclosure is the motor core manufacturing apparatus according to any one of the first to fourth aspects of the present disclosure, wherein the screw includes a cylindrical first screw body having fins formed around its outer periphery for transporting the resin composition and a closed tip, and a first flow path forming member consisting of a cylindrical body having a through hole extending along the longitudinal direction in its center and having a plurality of grooves extending along the longitudinal direction formed around its outer periphery, and the first flow path forming member is fitted into the first screw body so that a gap is formed between its tip and the bottom of the first screw body.

[0016] In the motor core manufacturing device as described above, an inlet channel and an outlet channel can be formed inside the screw by assembling two members, which makes it easier to process the parts used in the screw.

[0017] A motor core manufacturing apparatus according to a sixth aspect of the present disclosure is a motor core manufacturing apparatus according to any one of the first to fourth aspects of the present disclosure, wherein the screw includes a second screw body having fins formed around its outer periphery for transporting the resin composition and having a plurality of through holes formed inside the screw and extending along the longitudinal direction, and a second flow path forming member connected to the tip of the second screw body to connect the ends of the plurality of through holes to each other.

[0018] In the motor core manufacturing device as described above, an inlet channel and an outlet channel can be formed inside the screw by assembling two members, which makes it easier to process the parts used in the screw.

[0019] A motor core manufacturing apparatus according to a seventh aspect of the present disclosure is a motor core manufacturing apparatus according to the sixth aspect of the present disclosure, wherein the second screw body is formed by connecting a plurality of divided bodies, each having the fins formed on its outer periphery and a plurality of through holes extending longitudinally inside, so that the plurality of through holes are in communication with each other.

[0020] In the motor core manufacturing device as described above, the screw body can be formed by connecting a plurality of divided bodies, so the length of the screw body can be easily changed.

[0021] A method for manufacturing a motor core according to an eighth aspect of the present disclosure includes the steps of: holding the motor core in a mold having a resin composition filling passage formed therein so that the resin composition filling passage is connected to the resin filling portion of the motor core; using an extruder capable of conveying a resin composition to convey the resin composition toward a chamber communicating with the resin composition filling passage while adjusting the temperature, the extruder having an extrusion conveying passage through which the resin composition is conveyed, a screw disposed in the extrusion conveying passage for conveying the resin composition while kneading it, and a first temperature control mechanism disposed at least partially inside the screw; operating a plunger movable within the chamber to fill the softened resin composition in the chamber into the resin filling portion; and hardening the softened resin composition filled in the resin filling portion.

[0022] In the motor core manufacturing method described above, the resin composition to be introduced into the chamber does not need to be preformed into tablets. The amount of resin composition supplied to the chamber can be easily adjusted, thereby reducing resin composition loss. Furthermore, the resin composition can be conveyed to the chamber while its temperature is controlled using, for example, a first temperature control mechanism. For example, the first temperature control mechanism can be used to cool the resin composition, thereby suppressing temperature increases due to shear heat generated during conveyance. This suppresses unintended curing reactions during conveyance of the resin composition and prevents incomplete filling of the resin composition. Furthermore, using the first temperature control mechanism to heat the resin composition can facilitate rapid temperature increases when the resin composition is heated in the extruder. Furthermore, shear heat generated during conveyance of the resin composition often occurs locally, potentially causing temperature unevenness. Heating the resin composition using the first temperature control mechanism can also be expected to suppress this temperature unevenness. [Effects of the Invention]

[0023] According to the motor core manufacturing apparatus and motor core manufacturing method of the present disclosure, it is possible to suppress resin composition loss while also suppressing imperfect filling of the resin composition. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a schematic explanatory diagram illustrating an example of a motor core manufacturing apparatus according to an embodiment of the present disclosure. [Figure 2A] 2 is an explanatory diagram showing a part of a first temperature control mechanism of the motor core manufacturing apparatus shown in FIG. 1, and is a cross-sectional view and a side view showing one state of the screw manufacturing process. FIG. [Figure 2B] 2 is an explanatory diagram showing a part of a first temperature control mechanism of the motor core manufacturing apparatus shown in FIG. 1, and is a cross-sectional view and a side view showing one state of the screw manufacturing process. FIG. [Figure 2C] 2 is an explanatory view showing a part of a first temperature adjustment mechanism of the motor core manufacturing apparatus shown in FIG. 1, and is a cross-sectional view and one side view showing a manufactured screw. FIG. [Figure 3A] 3 is an explanatory view showing a first modified example of the screw shown in FIG. 2, including a cross-sectional view and one side view showing a first screw body. FIG. [Figure 3B] 3 is an explanatory view showing a first modified example of the screw shown in FIG. 2, showing a cross-sectional view and one side view showing a first flow path forming member. FIG. [Figure 3C] 3 is an explanatory view showing a first modified example of the screw shown in FIG. 2, showing a cross-sectional view and one side view of the screw according to the first modified example. FIG. [Figure 4A] 3 is an explanatory view showing a second modified example of the screw shown in FIG. 2, and is a cross-sectional view and one side view showing a state before the second screw body and the second flow path forming member are assembled. FIG. [Figure 4B] 3 is an explanatory diagram showing a second modified example of the screw shown in FIG. 2, and is a cross-sectional view and one side view showing the state after the second screw body and the second flow path forming member are assembled. [Figure 5] 3 is a flowchart illustrating an example of a method for manufacturing a motor core according to an embodiment of the present disclosure. [Figure 6A]6 is an explanatory diagram showing an example of an operating state of the motor core manufacturing apparatus shown in FIG. 1 when the motor core manufacturing method shown in FIG. 5 is performed. [Figure 6B] 6 is an explanatory diagram showing an example of an operating state of the motor core manufacturing apparatus shown in FIG. 1 when the motor core manufacturing method shown in FIG. 5 is performed. [Figure 7A] 6 is an explanatory diagram showing an example of an operating state of the motor core manufacturing apparatus shown in FIG. 1 when the motor core manufacturing method shown in FIG. 5 is performed. [Figure 7B] 6 is an explanatory diagram showing an example of an operating state of the motor core manufacturing apparatus shown in FIG. 1 when the motor core manufacturing method shown in FIG. 5 is performed. [Figure 8A] 6 is an explanatory diagram showing an example of an operating state of the motor core manufacturing apparatus shown in FIG. 1 when the motor core manufacturing method shown in FIG. 5 is performed. [Figure 8B] 6 is an explanatory diagram showing an example of an operating state of the motor core manufacturing apparatus shown in FIG. 1 when the motor core manufacturing method shown in FIG. 5 is performed. DETAILED DESCRIPTION OF THE INVENTION

[0025] This application is based on Patent Application No. 2022-092469 filed in Japan on June 7, 2022, the contents of which form part of the contents of this application. The present disclosure will become more fully understood from the following detailed description. Further scope of application of the present application will become apparent from the following detailed description. However, the detailed description and specific examples are preferred embodiments of the present disclosure and are set forth for illustrative purposes only. From this detailed description, various changes and modifications will become apparent to those skilled in the art within the spirit and scope of the present disclosure. Applicant does not intend to dedicate any of the described embodiments to the public, and all disclosed modifications and alternatives, which may not literally fall within the scope of the claims, are considered part of the invention under the doctrine of equivalents.

[0026] Hereinafter, each embodiment for carrying out the present disclosure will be described with reference to the drawings. Note that the scope necessary for the explanation to achieve the object of the present disclosure will be schematically shown below, and the scope necessary for explaining the relevant parts of the present disclosure will be mainly explained, and the parts for which explanation is omitted will be referred to as publicly known technologies. Furthermore, identical or corresponding components in the drawings will be given the same or similar reference numerals, and redundant explanations will be omitted. Furthermore, when a single drawing includes multiple identical or corresponding components, only some of them may be given reference numerals to make the drawing easier to understand.

[0027] <Motor core manufacturing equipment> FIG. 1 is a schematic diagram illustrating an example of a motor core manufacturing apparatus according to an embodiment of the present disclosure. The motor core manufacturing apparatus 1 according to this embodiment may be an apparatus for attaching permanent magnets 3 to a motor core, for example, an inner-rotor rotor core 2. The permanent magnets 3 may be attached by resin molding. While this embodiment illustrates the rotor core 2 as an example of the motor core and the slots 4 (more specifically, the filled spaces 6) of the rotor core 2 as an example of a resin-filled portion of the motor core, the present disclosure is not limited thereto. Specifically, the motor core manufacturing apparatus 1 may be used, for example, to resin-mold the coil-wound portion of a stator core serving as a motor core, or to fill axial through-holes of an uncrimped laminated core with resin to secure the laminated core together. For ease of understanding, the following description may refer to the X direction in FIG. 1 as the left-right direction, the Y direction as the front-rear direction, and the Z direction as the height direction (or up-down direction).

[0028] The resin composition P used in the motor core manufacturing apparatus 1 according to this embodiment is a thermosetting resin composition. More specifically, it may contain a thermosetting resin such as an epoxy resin, a phenolic resin, an unsaturated polyester resin, or a cyanate resin. In addition to the thermosetting resin, the resin composition P may also contain a curing agent, a filler, or the like.

[0029] As shown in Figure 1, the motor core manufacturing apparatus 1 of this embodiment includes at least a manufacturing apparatus main body 10, a mold 20 for holding the rotor core 2, a chamber 30 capable of containing a resin composition P, a plunger 35 for transporting the resin composition P in the chamber 30, a heater 40 as an example of a heater capable of heating the mold 20 and the chamber 30, and an extruder 50 for injecting the resin composition P into the chamber 30.

[0030] The manufacturing apparatus main body 10 may include a base 11, a plurality of (for example, four) support columns 12 erected on the surface of the base 11, and a top plate 13 supported at the tip portions of the support columns 12. The top plate 13 may have an upper mold 21 of a mold 20 (described later) fixed to its lower surface, and may be able to move up and down together with the support columns 12 and the upper mold 21 by using an actuator (not shown).

[0031] The mold 20 is a member for holding the rotor core 2. Specifically, the mold 20 can include an upper mold 21 that abuts against and supports the upper part of the rotor core 2, more specifically, the upper surface, and a lower mold 22 that abuts against and supports the lower part of the rotor core 2, more specifically, the lower surface. Of these, the lower mold 22 may include a lower mold main body 23 and a stage 24 that is provided on the lower mold main body 23 and on which the rotor core 2 is placed. The rotor core 2 can be placed on this stage 24 or transported from on the stage 24 by a robot arm (not shown) or the like.

[0032] Additionally, a resin composition filling passage 25 may be provided inside the stage 24 for supplying the resin composition P to an appropriate location of the rotor core 2 placed on the stage 24. The path structure of the resin composition filling passage 25 may be changed to match the structure of the rotor core 2 placed on the stage 24. A plurality of stages 24 having different resin composition filling passage 25 structures may be prepared in advance and used by appropriately changing the stage 24 to match the dimensions of the rotor core 2 held in the mold 20, the position of the slots 4, and the like. The lower mold 22 may further include a lifter 26 that raises and lowers the stage 24 for cleaning the resin composition filling passage 25, etc. While this embodiment illustrates an embodiment in which the resin composition filling passage 25 is provided in the lower mold 22 and the resin composition P is filled from below, the present invention is not limited thereto. For example, a resin composition filling passage may be provided in the upper mold 21 and the resin composition P may be filled from above.

[0033] Furthermore, the upper mold 21 may be movable in the vertical direction together with the top plate 13, as described above. When the rotor core 2 is placed on the stage 24, the upper mold 21 descends and presses the upper surface of the rotor core 2 with a predetermined pressing force, thereby holding the rotor core 2 sandwiched between the upper mold 21 and the lower mold 22. The shapes, materials, and the like of the surfaces of the upper mold 21 and the stage 24 that contact the rotor core 2 are preferably adjusted so that the resin composition P described below does not leak out of the rotor core 2 when the resin composition P is filled therein; in other words, so that the contact surfaces are sealed when the rotor core 2 is sandwiched. Furthermore, in this embodiment, a structure is adopted in which the upper mold 21 moves up and down together with the top plate 13, as described above. However, other structures may be adopted as long as the vertical positions of the upper mold 21 and the lower mold 22 can be changed relatively. Specifically, for example, instead of moving the upper mold 21 in the vertical direction, the lower mold 22 may be moved in the vertical direction, or a structure in which both the upper mold 21 and the lower mold 22 are moved may be adopted.

[0034] In this embodiment, the slot portion 4 of the rotor core 2 is exemplified as a rectangular parallelepiped with substantially no gaps in the front-rear and left-right directions. Therefore, the upper mold 21 and the lower mold 22 have substantially flat contact surfaces, but the shapes of the contact surfaces of the upper mold 21 and the lower mold 22 can be changed as appropriate to match the shape of the rotor core 2 to be held. For example, when the motor core manufacturing apparatus 1 according to this embodiment is used for resin molding of an inner rotor type stator core, it is preferable to use the upper mold 21 and the lower mold 22 that include protrusions that are inserted into spaces formed in the center of the stator core.

[0035] The rotor core 2 held in the mold 20 described above can be made of a substantially cylindrical magnetic material, for example, made by laminating multiple thin electromagnetic steel sheets. A through hole 5 may be provided in the axial center portion of the rotor core 2, into which a shaft that constitutes a rotating shaft when assembled into a motor is inserted. One or more slots 4 may be provided surrounding this through hole 5 and extending along the axial direction of the rotor core 2. The slots 4 can be formed, for example, in a rectangular parallelepiped shape, but the specific shape is not particularly limited as long as the shape allows for the insertion of permanent magnets 3, which will be described later.

[0036] The slots 4 of the rotor core 2 may have permanent magnets 3 inserted and fixed therein. The permanent magnets 3 may be configured, for example, as rectangular parallelepipeds slightly smaller than the slots 4. Furthermore, the permanent magnets 3 may be magnetized or not. When the permanent magnets 3 are inserted into the slots 4, at least a partial gap is formed between the outer peripheral surface of the permanent magnet 3 and the inner peripheral surface of the slots 4. This gap can function as a filling space 6, which is an example of a resin filling section. When the rotor core 2 is placed on the stage 24, a portion of each of the multiple filling spaces 6 can communicate with an end of the resin composition filling path 25.

[0037] The chamber 30 may form a space into which a predetermined amount of resin composition P to be filled into the filling space 6 is poured. The chamber 30 may be formed so as to extend in the vertical direction inside a support stand 31 provided on the base 11. The upper end of the chamber 30 may be in communication with a resin composition filling passage 25 of a stage 24 included in a lower mold 22 disposed on the support stand 31.

[0038] The plunger 35 may be a member for transporting the resin composition P transported into the chamber 30 toward the resin composition filling path 25. The plunger 35 according to this embodiment may form the lower surface of the chamber 30, and may be connected to an actuator (not shown) so as to be movable up and down within the chamber 30.

[0039] Heater 40 may be composed of a known heater or the like, and may heat appropriate locations in manufacturing apparatus 1. Heater 40 according to this embodiment may include a mold heater 41 disposed within mold 20, specifically within upper mold 21 and lower mold body 23, and a chamber heater 42 disposed around chamber 30 within support base 31 so as to be close to the outer periphery of chamber 30. Known heaters, for example, infrared heaters and sheath heaters, may be used as mold heater 41 and chamber heater 42.

[0040] The extruder (sometimes referred to as an "extruder") 50 may have one end connected to the chamber 30 and be capable of kneading and transporting the resin composition P toward the chamber 30. The extruder 50 includes at least a barrel 51 as an example of an extrusion transport path through which the resin composition P is transported, and a screw 52 disposed inside the barrel 51 and transporting the resin composition P, for example, a powdery resin composition P1, supplied into the barrel 51 while kneading it. While the present embodiment illustrates an example of the extruder 50 extending in the left-right direction, the extension direction of the extruder 50 is not limited thereto. For example, the extruder 50 may extend obliquely upward from the chamber 30 or may extend vertically alongside the chamber 30. When the extruder 50 and the chamber 30 are disposed side by side, it is preferable to provide a space between the extruder 50 and the chamber 30 for transporting the resin composition P. In addition, in the present disclosure, a case where a powdery resin composition P1 is supplied as the resin composition P supplied to the barrel 51 is exemplified, but the resin composition P is not limited to being powdery and may be in other shapes, for example, at least a portion of which may be in a paste or pellet form. Furthermore, the powdery resin composition P1 in the present disclosure refers to a resin composition P1 formed of relatively small particles such as granules (these particles also include small pieces obtained by crushing and crushing a relatively large resin block).

[0041] The barrel 51 may be a conveying path extending in one direction, for example, the left-right direction, for conveying the resin composition P while kneading it. One end of the barrel 51 may be formed with a supply port 53 through which the powdery resin composition P1 is supplied, and the other end may be formed with an unloading port 54 connected to the chamber 30. A resin composition supply source 58 may be connected to the supply port 53 via a resin composition supply path 57. The unloading port 54 may be provided with, for example, a sliding or rotating shutter 56.

[0042] The screw 52 may be configured as a long member having a spiral fin 52F formed on its outer periphery and rotated by a motor 59 connected to one end. The screw 52 may be disposed within the barrel 51 along its extension direction so as to convey the powdered resin composition P1 supplied from a supply port 53 toward an outlet 54 while kneading it. Furthermore, if the powdered resin composition P1 is continuously supplied to the screw 52, ​​the resin composition P can be pressurized during conveyance. Therefore, the powdered resin composition P1 conveyed within the barrel 51 may be gradually transformed into a paste-like resin composition P2 by being kneaded and pressurized by the screw 52 during conveyance. The term "paste-like" as used herein refers to a state in which the powdered resin composition P has united to form a mass, resulting in a paste or clay-like state.

[0043] The motor 59 connected to the screw 52 can adjust the amount of resin composition P conveyed by changing its rotation speed. Therefore, the amount of paste-like resin composition P2 fed from the extruder 50 to the chamber 30 can be accurately adjusted by controlling the rotation speed of the motor 59. Note that the paste-like resin composition P2 referred to here may be a mixture of the paste-like resin composition P2 and the powdery resin composition P1. Although the present embodiment illustrates an example in which the amount of paste-like resin composition P2 fed to the chamber 30 is controlled by the rotation speed of the motor 59, the control of the amount fed is not limited to this method. For example, the amount of paste-like resin composition P2 fed to the chamber 30 can also be controlled based on the volume of the paste-like resin composition P2 in the barrel 51 or the thrust force required to convey the paste-like resin composition P2.

[0044] The extruder 50 may further include a temperature sensor that detects the temperature of the powdery resin composition P1 or the paste-like resin composition P2 being conveyed inside the barrel 51, or the room temperature inside the barrel 51. Then, by controlling the rotation speed of the motor 59 based on the detection result of the temperature sensor and a preset amount of the resin composition being fed into the chamber 30, it is possible to more accurately adjust the amount of the paste-like resin composition P2 being fed into the chamber 30. Note that although the extruder 50 according to the present embodiment is exemplified as an extruder having one screw 52, ​​the number of screws 52 may be two or more.

[0045] Furthermore, in order to control each component such as the motor 59 described above, the manufacturing apparatus 1 according to this embodiment may further include a control device 60. The control device 60 may be communicably connected to each component via wired or wireless communication, for example, as shown by the dotted lines in Fig. 1. This control device 60 may be realized using a sequencer (Programmable Logic Controller, PLC) or a well-known computer.

[0046] The motor core manufacturing apparatus 1 according to this embodiment mainly employs the extruder 50 having the above-described configuration, and is therefore able to supply any amount of resin composition P to the chamber 30 without using pre-formed tablet-shaped resin composition. This allows the amount of resin composition P conveyed to the chamber 30 (i.e., the amount introduced into the chamber 30) to be freely adjusted by controlling the rotation speed of the motor 59, making it possible to freely change the amount introduced into the chamber 30 and reduce loss of resin composition P during the manufacturing process. Furthermore, there is no longer any need to select a resin tablet to match the amount of resin composition to be filled into the motor core (resin composition filling amount).

[0047] On the other hand, in an extruder that uses a screw 52 for kneading and conveying the resin composition P, such as the extruder 50 described above, the resin composition P is subjected to shear deformation by the screw 52 during conveyance. Therefore, shear heat generated during the deformation may cause at least a partial increase in the temperature of the resin composition P. When a thermosetting resin composition P is used, as in the present embodiment, the shear heat may cause a curing reaction to proceed unintentionally, and a portion of the resin composition may harden within the barrel 51.

[0048] The unintended progress of the curing reaction of the resin composition P in the barrel 51 as described above can cause various problems, such as variations in the amount of resin composition P supplied to the chamber 30, increased frequency of cleaning of the extruder 50, or the resin composition being caught in the curing reaction, causing the rotation of the screw 52 to stop. In addition, the unintended progress of the curing reaction described above can cause variations in the (melt) viscosity of the resin composition P supplied to the chamber 30. If the (melt) viscosity becomes too high, it can impair the flowability within the resin composition filling passage 25 and the slots 4, making it impossible to fill the filling space 6 in the rotor core 2 with the resin composition P. In consideration of this, the motor core manufacturing apparatus 1 according to this embodiment employs a first temperature control mechanism 70 to suppress the unintended temperature rise of the resin composition P. The first temperature control mechanism 70 will be described below.

[0049] Fig. 2 is a diagram showing a part of the first temperature control mechanism of the motor core manufacturing apparatus shown in Fig. 1, Figs. 2A and 2B are a cross-sectional view and a side view showing one state of the screw manufacturing process, and Fig. 2C is a cross-sectional view and a side view showing the manufactured screw. Note that Fig. 2 does not show fins 52F formed around the screw 52. Each cross-sectional view shown in Fig. 2 is obtained by cutting the screw 52 along a plane extending in the longitudinal direction passing through its central axis, and one side view shows the base end surface of the screw 52 that is connected to the motor 59.

[0050] As shown in FIG. 2C , the first temperature adjustment mechanism 70 of the motor core manufacturing apparatus 1 according to this embodiment is at least partially disposed inside the screw 52, ​​thereby suppressing a temperature rise in the resin composition P being kneaded and conveyed by the screw 52. The heat medium used in the first temperature adjustment mechanism 70 may be a gas. Specifically, the first temperature adjustment mechanism 70 of this embodiment may be an air-cooled cooling mechanism that uses air as the heat medium, and may include an inlet channel 74 and an outlet channel 75 provided within the screw 52. As described above, using a gas as the heat medium for the first temperature adjustment mechanism 70 makes it easier to handle than using a cooling mechanism that uses a liquid such as water as the heat medium.

[0051] In this embodiment, the first temperature adjustment mechanism 70 is exemplified as one intended to cool the resin composition P, but by adjusting the temperature of the heat medium, the first temperature adjustment mechanism 70 can also be used to keep the resin composition P warm or heat it. In other words, the first temperature adjustment mechanism 70 can be said to adjust the temperature of the resin composition P being transported inside the barrel 51.

[0052] Using the first temperature adjustment mechanism 70 to heat the resin composition P can assist in rapid temperature increase, for example, when it is desired to increase the temperature of the resin composition P in the extruder 50. Furthermore, shear heat that occurs when the resin composition P is conveyed in the extruder 50 often occurs locally in the barrel 51, which can cause temperature unevenness, but heating the resin composition P in the barrel 51 with the first temperature adjustment mechanism 70 can be expected to have the effect of suppressing this temperature unevenness.

[0053] More specifically, as shown in Figures 1 and 2C, the first temperature adjustment mechanism 70 of this embodiment can include a blower 71 as an example of a heat medium supply source, and a screw 52 having an inlet passage 74 and an outlet passage 75 therein through which air supplied from the blower 71 passes.

[0054] The blower 71 is an example of a heat medium supply source, and can be connected to a heat medium supply port provided at the base end of an inlet channel 74 formed in the screw 52, ​​and can supply air as a heat medium into the inlet channel 74. In this embodiment, an air-cooled cooling mechanism is used in the first temperature adjustment mechanism 70, and therefore air is used as the heat medium, but the heat medium is not limited to this. Specifically, water or other fluids can also be used as the heat medium. In that case, other heat medium supply means can be used instead of the blower 71.

[0055] The screw 52 may have an inlet channel 74 formed at its center and a plurality of outlet channels 75 formed in proximity to its outer circumferential surface. The inlet channel 74 may be configured as a passage extending along the central axis of the screw 52, ​​with one end located on the base end side of the screw 52 opening at the end of the screw 52 to form a heat medium supply port and the other end located on the tip end side of the screw 52 communicating with the outlet channel 75. The outlet channel 75 may be configured as a plurality of passages (two in FIG. 2 ) extending substantially parallel to the inlet channel 74 between the inlet channel 74 and the outer circumferential surface of the screw 52. The outlet channel 75 may be a passage having one end located on the tip end side of the screw 52 communicating with the other end of the inlet channel 74 and the other end located on the base end side of the screw 52 communicating with the outside of the barrel 51.

[0056] As described above, forming the inlet channel 74 along the central axis of the screw 52 is preferable because it simplifies the connection structure between the inlet channel 74 formed in the rotating screw 52 and the blower 71. In this regard, since the first temperature adjustment mechanism 70 of the present embodiment uses air as the heat medium, it is not necessary to collect the air that has left the outlet channel 75. Therefore, the other end of the outlet channel 75 only needs to be connected to the outside of the barrel 51. Note that, in the present embodiment, two outlet channels 75 are provided to sandwich the inlet channel 74 from above and below, but the arrangement and number of the outlet channels 75 can be changed as appropriate. For example, four outlet channels 75 can be provided to sandwich the inlet channel 74 from both above and below and left and right.

[0057] The other end of the inlet channel 74 and one end of the outlet channel 75 are in communication with each other via a communication channel 76. As shown in FIG. 2C , this communication channel 76 can be formed as a channel extending in a direction intersecting the extension direction of the screw 52. The first temperature adjustment mechanism 70 is capable of cooling the screw 52 and the resin composition P being transported around the screw 52 by passing air as a heat medium mainly through the inside of this communication channel 76 and the outlet channel 75. Therefore, it is preferable that the communication channel 76 and the outlet channel 75 be disposed in proximity to the outer peripheral surface of the screw 52.

[0058] An example of a manufacturing method for the screw 52 including the above-described configuration will be briefly described below. First, as shown in FIG. 2A, three blind holes are formed along the longitudinal direction of the long screw 52 from the base end side. Each of these blind holes can form an inlet channel 74 and an outlet channel 75. Next, as shown in FIG. 2B, a through hole is formed from the outer peripheral surface of the screw 52 so as to cross the bottoms of the three blind holes. This through hole can form a communicating channel 76. Finally, by closing the two openings of the through hole with a sealing member 76S, a screw 52 can be provided that includes an inlet channel 74 and an outlet channel 75 whose ends are connected by the communicating channel 76.

[0059] In the motor core manufacturing apparatus 1 according to this embodiment, when the screw 52 is operated to transport the resin composition P to the chamber 30, the first temperature adjustment mechanism 70 including the above-described configuration is operated. This allows the screw 52 and the resin composition P being transported while being kneaded around the screw 52 to be cooled. This makes it possible to suppress an unintended temperature rise due to shear heat that occurs during transport by the screw 52, ​​and effectively suppresses filling defects caused by the progress of the curing reaction of the resin composition P before filling; more specifically, failure to transport the resin composition P inside the barrel 51 and an increase in the frequency of cleaning work inside the barrel 51.

[0060] To more reliably suppress temperature increases due to shear heat generated in the resin composition P, the motor core manufacturing apparatus 1 according to this embodiment can also be provided with a second temperature control mechanism 80 on the barrel 51 side in addition to the first temperature control mechanism 70 described above. As shown in FIG. 1, the second temperature control mechanism 80 is preferably provided at least in a portion of the barrel 51 that surrounds the screw 52. The second temperature control mechanism 80 can be configured, for example, with a heat medium passage routed inside the barrel 51. The heat medium supplied to the heat medium passage is not particularly limited, but water, air, etc. can be used.

[0061] By employing the above-described second temperature control mechanism 80 in addition to the first temperature control mechanism 70, the resin composition P being kneaded and conveyed by the screw 52 can be cooled or heated from both the inside and outside. Therefore, by using these temperature control mechanisms for cooling, it becomes possible to more effectively suppress the temperature rise of the resin composition P caused by shear heat. Conversely, by using these temperature control mechanisms for heating the resin composition P, more uniform heating can be achieved.

[0062] The cooling of the resin composition P by the first temperature adjustment mechanism 70, or the first temperature adjustment mechanism 70 and the second temperature adjustment mechanism 80, can be operated at any timing while the resin composition P is being transported so that the temperature of the transported resin composition P becomes 100° C. or less, preferably 70° C. or less, and more preferably 60° C. or less. Specific control of these temperature adjustment mechanisms 70 and 80 can be performed mainly by the control device 60.

[0063] In addition, in the motor core manufacturing apparatus 1 according to the present embodiment, screw 52 of first temperature adjustment mechanism 70 is manufactured through the steps shown in Fig. 2, but it can also be manufactured through methods other than this manufacturing method. Therefore, several examples of screw bodies manufactured through manufacturing methods other than the above-described method will be described below.

[0064] Fig. 3 is an explanatory diagram showing a first modified example of the screw shown in Fig. 2, in which Fig. 3A is a cross-sectional view and one side view showing a first screw body, Fig. 3B is a cross-sectional view and one side view showing a first flow path forming member, and Fig. 3C is a cross-sectional view and one side view of the screw according to the first modified example. As shown in Fig. 3C, the screw 52A according to the first modified example may include a first screw body 72A and a first flow path forming member 73A.

[0065] As shown in Fig. 3A, the first screw body 72A can be configured as a cylindrical member having a closed tip end to form a blind hole 72H extending longitudinally therein. Fins 52F are formed around the outer periphery of this first screw body 72A, but are not shown in Fig. 3. The base end of this first screw body 72A, where the blind hole 72H is open, is connected to the motor 59, and the tip end can be disposed in the barrel 51 as a free end.

[0066] 3B, the first flow path forming member 73A can be configured as a cylindrical body having a through hole 77 extending in the longitudinal direction at its center. The first flow path forming member 73A made of this cylindrical body may have a plurality of, for example, four, recessed grooves 78 formed in the outer periphery thereof extending in the longitudinal direction. The outer diameter of the first flow path forming member 73A is preferably adjusted so that it can be fitted into the bottomed hole 72H of the first screw body 72A.

[0067] Furthermore, it is preferable that a rotation prevention structure (not shown) be provided on the outer peripheral surface of the first flow path forming member 73A where the recessed groove 78 is not formed, so that the first flow path forming member 73A rotates together with the first screw body 72A when fitted into the first screw body 72A. A well-known interlocking shape or the like can be used as this rotation prevention structure.

[0068] 3C, the screw 52A according to the first modified example can be constructed by fitting (or press-fitting) a first flow path forming member 73A into the bottomed hole 72H of the first screw body 72A described above. When the first flow path forming member 73A is fitted into the bottomed hole 72H, the fitting length of the first flow path forming member 73A is set to be shorter than the depth of the bottomed hole 72H. This forms a gap between the tip of the first flow path forming member 73A and the bottom surface of the bottomed hole 72H that forms the bottom inside the first screw body 72A, and this gap can function as a communicating passage 76.

[0069] The inlet passage 74 formed in the screw 52A can be formed by a through hole 77 of the first flow path forming member 73A fitted into the bottomed hole 72H. Similarly, the outlet passage 75 formed in the screw 52A can be formed by four passages defined by the inner circumferential surface of the bottomed hole 72H and the recessed grooves 78 of the first flow path forming member 73A fitted into the bottomed hole 72H. One end of the inlet passage 74 formed in the screw 52A can be communicated with one end of each outlet passage 75 via the above-mentioned communication passages 76. In this way, manufacturing the screw 52A by assembling two members can simplify the machining of the part.

[0070] Fig. 4 is an explanatory diagram showing a second modified example of the screw shown in Fig. 2, Fig. 4A is a cross-sectional view and one side view showing a state before the second screw body and the second flow path forming member are assembled, and Fig. 4B is a cross-sectional view and one side view showing a state after the second screw body and the second flow path forming member are assembled. As shown in Fig. 4B, a screw 52B according to the second modified example may include a second screw body 72B and a second flow path forming member 73B.

[0071] As shown in FIGS. 4A and 4B , the second screw body 72B may be configured as a columnar member having a plurality of through holes 74B, 75B formed therein and extending along the longitudinal direction. Fins 52F are formed around the outer periphery of the second screw body 72B, similar to those of the first screw body 72A, but are not shown in FIG. 4 . The base end of the second screw body 72B may be connected to the motor 59, and the tip end may be disposed as a free end within the barrel 51. The through holes 74B, 75B formed in the second screw body 72B may include one through hole 74B extending along the central axis of the second screw body 72B and capable of forming the inlet channel 74, and a plurality of other through holes 75B arranged around the one through hole 74B and extending substantially parallel to the one through hole 74B and capable of forming the outlet channel 75.

[0072] As an option, the second screw body 72B according to this modification can be formed by connecting multiple segments (e.g., three segments 72B1-72B3) as shown in FIG. 4A. The segments 72B1-72B3 can be formed as columnar members with fins 52F formed around their outer peripheries and multiple through-holes 74B, 75B extending along the longitudinal direction within. The second screw body 72B can be formed by connecting the segments 72B1-72B3 so that the multiple through-holes 74B, 75B of each segment 72B1-72B3 are in communication with each other. By adopting a structure in which multiple segments 72B1-72B3 are connected to form a single second screw body 72B, the length of the screw 52B can be easily changed by appropriately changing the number of segments connected as described above.

[0073] The second flow path forming member 73B may be connected to the tip end portion of the second screw body 72B and may connect the ends of the multiple through holes 74B, 75B provided in this second screw body 72B. This second flow path forming member 73B may be configured as a columnar member whose outer diameter dimension is adjusted to match the second screw body 72B. Furthermore, a communication passage 76B may be formed in the base end portion of this second flow path forming member 73B to connect the tip end of one through hole 74B with the tips of the two other through holes 75B.

[0074] The communicating passage 76B can be formed, for example, by a bottomed hole extending from the base end side of the second flow path forming member 73B along the central axis of the second flow path forming member 73B, and two bottomed holes extending from the base end side of the second flow path forming member 73B in a direction inclined with respect to the central axis of the second flow path forming member 73B so as to communicate with the bottom of the bottomed hole. In this modified example, the communicating passage 76B can be formed simply by drilling three bottomed holes extending linearly, and therefore the processing is easy.

[0075] As shown in Fig. 4B, the screw 52B according to the second modified example can be constructed by axially connecting the above-described second screw body 72B and second flow path forming member 73B. In this modified example, the screw 52B can also be manufactured by connecting multiple members, which simplifies the processing of the parts. Furthermore, because the screw 52B can be divided into multiple components, it becomes easier to process the holes formed in each of the divided bodies 72B1 to 72B3 and the second flow path forming member 73B (specifically, the through holes 74B and 75B and the blind holes that form the communicating passages 76B).

[0076] Returning to the explanation of the extruder 50, a waiting space 51A of a predetermined size without the screw 52 may be formed between the discharge port 54 of the barrel 51 and the tip (more specifically, the free end) of the screw 52. This waiting space 51A may be a space for temporarily storing the paste-like resin composition P2 kneaded and transported by the rotation of the screw 52 in a state where the temperature is controlled by the first temperature control mechanism 70. Furthermore, this waiting space 51A may be provided with a well-known transport means (not shown), such as a belt conveyor or a scraper. This transport means can be operated, for example, in conjunction with the opening of the shutter 56, to instantly introduce a specific amount of the paste-like resin composition P2 temporarily stored in the waiting space 51A into the chamber 30.

[0077] As an option, a barrel heater 55 is preferably provided around the periphery of the waiting space 51A to preheat the paste-like resin composition P2 transported to the waiting space 51A by the screw 52. This barrel heater 55 can be configured with a known heater similar to the mold heater 41, and can be provided, for example, so as to surround substantially the entire periphery of the waiting space 51A. The barrel heater 55 can preheat the paste-like resin composition P2 in the waiting space 51A to 50 to 100°C, more preferably 90 to 100°C. By employing this barrel heater 55, the paste-like resin composition P2 transported to the waiting space 51A can be heated before being introduced into the chamber 30, thereby accelerating softening. This significantly reduces the heating time required to soften and melt the paste-like resin composition P2 in the chamber 30.

[0078] In the present embodiment, a structure in which the discharge port 54 of the barrel 51 is connected to the chamber and a standby space 51A is provided adjacent to the discharge port 54 has been exemplified, but the present disclosure is not limited thereto. For example, a conveying mechanism (not shown) may be provided between the discharge port 54 of the barrel 51 and the chamber 30, and the paste-like resin composition P2 may be introduced into the chamber 30 by operating the conveying mechanism. Similarly, a mechanism for removing air from the kneaded paste-like resin composition P2 may be additionally provided between the discharge port 54 of the barrel 51 and the shutter 56 or the chamber 30. The mechanism may remove air from the paste-like resin composition P2 by, for example, compressing the paste-like resin composition P2 or providing a decompression chamber.

[0079] It is particularly important to note that the resin composition P introduced directly or indirectly into the chamber 30 from the extruder 50 of the motor core manufacturing apparatus 1 according to this embodiment is not a preformed tablet but a paste-like resin composition P2. By introducing the paste-like resin composition P2 into the chamber 30 in this manner, the amount of the resin composition P introduced into the chamber 30 can be freely adjusted by controlling the rotation speed of the motor 59, for example. The paste-like resin composition P2 introduced into the chamber 30 from the extruder 50 may be preformed into a predetermined shape. For example, the preformed resin composition P2 may be continuously transported to the waiting space 51A, where it is pressed against the shutter 56 to increase its density and thereby be preformed. The pressing of the paste-like resin composition P2 may also be achieved by temporarily moving the screw 52 itself along the transport direction. Alternatively, a jig (not shown) may be disposed between the extruder 50 and the chamber 30, and the paste-like resin composition P2 may be preformed into a desired shape using the jig.

[0080] As described above, the motor core manufacturing apparatus 1 according to this embodiment makes it possible to easily change the amount of resin composition P fed into the chamber 30 without preparing resin tablets of various sizes, thereby reducing loss of the resin composition P. In addition, because a uniformly heated paste-like resin composition P2 is fed, the resin composition P can be smoothly filled into the slot portion 4. Furthermore, the temperature of the resin composition P transported by the screw 52 can be controlled by the first temperature control mechanism 70, preventing unintended progress of the curing reaction of the resin composition P and thereby reducing the occurrence of filling defects.

[0081] <Motor core manufacturing method> Next, an example of a method for manufacturing a motor core according to this embodiment will be briefly described. Note that the following description will exemplarily illustrate a case in which the method for manufacturing a motor core according to this embodiment is carried out using the motor core manufacturing apparatus 1 according to the embodiment described above.

[0082] The motor core manufacturing method according to this embodiment includes the steps of: (1) holding rotor core 2 in mold 20, in which resin composition filling passage 25 is formed, so that resin composition filling passage 25 communicates with slots 4 (S4); (2) using extruder 50 capable of conveying resin composition P to convey a measured amount of resin composition P to chamber 30 communicating with resin composition filling passage 25 while adjusting the temperature (S5); (3) operating plunger 35 movable within chamber 30 to fill slots 4 with the softened resin composition (corresponding to liquid resin composition P3) from chamber 30 (S8); and (4) curing the softened resin composition filled in slots 4 (S9). These steps will be described in more detail below.

[0083] Fig. 5 is a flowchart showing an example of a motor core manufacturing method according to an embodiment of the present disclosure. Figs. 6 to 8 are explanatory diagrams showing an example of the operating state of the motor core manufacturing apparatus shown in Fig. 1 when the motor core manufacturing method shown in Fig. 5 is executed. The following description will be given mainly with reference to Figs. 5 to 8. Note that, in Figs. 6 to 8, for ease of viewing, reference numerals are primarily used to denote components relevant to each operation, and reference numerals for components less relevant to the operation may be omitted.

[0084] In the motor core manufacturing method according to this embodiment, first, motor core manufacturing apparatus 1 shown in FIG. 6A is prepared, and then the amount of resin composition P filled into filling space 6 of rotor core 2 (resin composition filling amount) is measured (step S1). This filling amount can be measured, for example, by measuring the volume of slot portion 4 of rotor core 2 and the volume of permanent magnet 3 inserted into slot portion 4, and then calculating the difference between them. The measured resin filling amount is sent to control device 60 and can be used to adjust the amount of resin composition P introduced into chamber 30, specifically, to control the rotation speed of motor 59, etc.

[0085] In the above-described step S1, the filling amount of the resin composition P is determined by measuring the volume of the slot portion 4 and the volume of the permanent magnet 3, but the filling amount may be determined by other methods. Specifically, for example, a trial production process may be performed before the start of mass production, and the filling amount may be determined based on the amount of resin filled and the amount of excess resin in the trial production process. Alternatively, the actual resin filling amount and the amount of excess resin may be checked during mass production at a frequency that does not interfere with mass production, and the filling amount may be feedback-controlled to maintain an appropriate filling amount. Furthermore, the various methods for determining the filling amount described above may be performed alone or in combination.

[0086] After measuring the required filling amount of resin composition P, permanent magnets 3 are inserted into the slots 4 of the rotor core 2 (step S2). Then, the mold 20 and rotor core 2 are preheated (step S3). The mold 20 can be preheated by operating the mold heater 41. At this time, it is preferable to preheat the chamber 30 along with the mold 20. The chamber 30 can be preheated by operating the chamber heater 42. The rotor core 2 can be preheated using a known heating means (not shown). The rotor core 2 can be preheated separately from the mold 20 before being placed on the stage 24, or it can be preheated simultaneously with the mold 20 while it is placed on the stage 24. When preheating the mold 20 and rotor core 2 simultaneously, it is preferable to perform step S4 (described later) before step S3. The mold 20 and rotor core 2 can be preheated to a temperature of approximately 100 to 180°C. Note that the preheating may be performed on only one of the mold 20 and the rotor core 2.

[0087] Once the preheating of the mold 20 and the rotor core 2 is complete, as shown in FIG. 6B , the rotor core 2 is placed on the stage 24, and the upper mold 21 is moved downward to hold the rotor core 2 in the mold 20 (step S4). At this time, the upper mold 21 is adjusted to press the upper surface of the rotor core 2 with a predetermined pressure, thereby bringing the upper mold 21 into close contact with the upper surface of the rotor core 2 and the lower mold 22 into close contact with the lower surface of the rotor core 2. Note that part of the measurement of the amount of resin composition P filled into the filling space 6 of the rotor core 2 can be performed while the rotor core 2 is being held. Specifically, the vertical height of the slot portion 4 can be determined from a control signal of an actuator (not shown) used to move the upper mold 21 in the vertical direction, and this can be used to measure the filling amount. In this case, the above-mentioned step S1 may be performed after step S4.

[0088] Next, the powdered resin composition P1 is kneaded and conveyed using an extruder 50 (step S5). In this step, the powdered resin composition P1 is first (e.g., continuously) supplied from a resin composition supply source 58 to a supply port 53 of a barrel 51, and the motor 59 is driven to rotate the screw 52, ​​thereby kneading and conveying the powdered resin composition P1 supplied to the supply port 53 to an outlet 54. In this step, in the motor core manufacturing apparatus 1 according to this embodiment, the first temperature control mechanism 70 and the second temperature control mechanism 80 are operated before or simultaneously with the rotation of the screw 52 to adjust the temperature of the conveyed resin composition P, for example, to cool it. This cooling operation can control the temperature rise of the resin composition P caused by the kneading and conveyance by the screw 52, ​​thereby suppressing the unintended progress of a curing reaction of the resin composition P.

[0089] In step S5, the rotation speed of the motor 59 may be controlled by the control device 60 so that the powdery resin composition P1 in an amount corresponding to the filling amount of the resin composition P measured in step S1 is converted into a paste-like resin composition P2 and transported to the waiting space 51A (see FIG. 6B). Note that the amount corresponding to the filling amount of the resin composition P here refers to the amount necessary to fill the filling space 6 with the resin composition P, taking into account not only the volume of the filling space 6 but also the volume of the resin composition filling path 25, etc. Note that the adjustment of the amount of the paste-like resin composition P2 introduced into the chamber 30 is not limited to the method based on the rotation speed of the motor 59 described above. For example, the amount of the paste-like resin composition P2 introduced into the chamber 30 may be adjusted by adjusting the amount of the powdery resin composition P1 supplied from the resin composition supply source 58 to match the filling amount of the resin composition measured in step S1. In addition, by providing a sensor (not shown), such as a weight sensor, in the waiting space 51A, the amount of the paste-like resin composition P2 stored in the waiting space 51A can be measured, and by comparing this with the previously measured filling amount of the resin composition, the amount of the paste-like resin composition P2 to be poured into the chamber 30 can be adjusted.

[0090] Furthermore, the resin composition P kneaded and transported in step S5 is transported to the waiting space 51A in the form of a paste-like resin composition P2, or in the form of a mixture of the granular resin composition P1 and the paste-like resin composition P2. At this time, the barrel heater 55 may be driven to preheat the resin composition P transported to the waiting space 51A. The preheating temperature by the barrel heater 55 can be adjusted, for example, within the range of 50 to 100°C. By the above-mentioned kneading and transport, most of the granular resin composition P1 supplied from the supply port 53 is converted into the paste-like resin composition P2 in the waiting space 51A.

[0091] When a predetermined amount of resin composition P is transported to the standby space 51A, as shown in FIG. 7A, the shutter 56 is opened, and the paste-like resin composition P2 temporarily stored in the standby space 51A is introduced into the chamber 30 using a transport means (not shown) (step S6). The amount of the paste-like resin composition P2 temporarily stored in the standby space 51A is adjusted to match the measured filling amount of the resin composition as described above. In addition, the paste-like resin composition P2 temporarily stored in the standby space 51A is preheated to 50 to 100°C by the barrel heater 55. The paste-like resin composition P2 has been transformed into a paste-like state by the preheating described above, and may become a solid mass, but it can be introduced into the chamber 30 without any problems.

[0092] After the paste-like resin composition P2 is introduced into the chamber 30, the shutter 56 is closed and the chamber heater 42 is operated to heat and soften the paste-like resin composition P2 (step S7). The chamber heater 42 can be controlled to heat the paste-like resin composition P2 in the chamber 30 to, for example, about 100 to 180°C. This heating softens and melts the paste-like resin composition P2, turning it into a highly fluid liquid resin composition P3. In the motor core manufacturing process according to this embodiment, the paste-like resin composition P2 has already been preheated to 50 to 100°C as described above, so the time required for softening in the chamber 30 is shorter than in the past.

[0093] Once the paste-like resin composition P2 has been transformed into the liquid resin composition P3 in step S7, the plunger 35 is raised as shown in FIG. 6B to push the liquid resin composition P3 toward the filling space 6 of the rotor core 2, thereby filling the resin composition P (step S8). The liquid resin composition P3 pushed up by the plunger 35 passes from the chamber 30 through the resin composition filling path 25 and flows into the filling space 6. In order to smoothly fill the filling space 6 with the liquid resin composition P3 in step S8, an air hole (not shown) for venting air from the filling space 6 may be provided in an appropriate position in the upper mold 21, for example.

[0094] Once the filling of the filling space 6 with the liquid resin composition P3 is completed, the mold heater 41 is operated to heat and harden the liquid resin composition P3 in the filling space 6 (step S9). When hardening the liquid resin composition P3, it is advisable to heat it at, for example, 100 to 180°C for several minutes. The heating transforms the liquid resin composition P3 into a hardened resin composition P4, and the permanent magnets 3 are fixed in the slot portions 4 of the rotor core 2 by the resin mold. The heating time in step S9 can be adjusted as appropriate depending on the specific composition of the resin composition P, etc.

[0095] When the series of resin molding steps described above are completed, as shown in FIG. 8A, the upper mold 21 is raised, and the resin-molded rotor core 2 is removed using a transport means (not shown), such as a robot arm (step S10). The removed rotor core 2 is then transferred to another device, for example, for the attachment of a shaft. Then, when removal of the rotor core 2 is complete, the manufacturing apparatus 1 is cleaned (step S11). The cleaning of the manufacturing apparatus 1 may be performed by a cleaning unit (not shown), which includes a cleaning member, such as a brush.

[0096] When cleaning the resin composition filling passage 25 of the stage 24 during the above-described cleaning, the following operation may be performed. That is, first, the lifter 26 is operated to separate the stage 24 from the lower mold body 23, thereby removing the cured resin composition P4 blocking the resin composition filling passage 25 from the resin composition filling passage 25. Then, the plunger 35 is further raised to separate the cured resin composition P4 from the lower mold body 23 (see FIG. 8B ). The separated cured resin composition P4 is then grasped and removed by a robot arm (not shown) or the like, and the surfaces of the stage 24 and the lower mold body 23 and the inside of the resin composition filling passage 25 are cleaned with a brush or the like. When the cleaning sequence is completed, the state returns to that shown in FIG. 6A and waits for the next rotor core 2 to be loaded.

[0097] The order of the above-described series of steps can be changed as long as the functions thereof can be maintained. For example, the conveyance of the powdered resin composition P1 or the paste-like resin composition P2 by the extruder 50 can be started at any timing after the filling amount of the resin composition P has been measured. Also, preheating of the mold 20, rotor core 2, resin composition P, etc. can be omitted.

[0098] As described above, the motor core manufacturing method according to this embodiment does not use a pre-formed tablet-shaped resin composition P to be charged into the chamber 30, and the required amount of resin composition P can be stably charged into the chamber 30 using the extruder 50, thereby reducing loss of the resin composition P. This eliminates the need to select a resin tablet according to the amount of resin to be filled into the motor core.

[0099] The present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure. All of these modifications are included in the technical concept of the present disclosure. Furthermore, in the present disclosure, each component may be present in only one form or in two or more forms, provided that no contradiction occurs.

[0100] All references, including publications, patent applications, and patents, cited in this specification are herein incorporated by reference to the same extent as if each reference was individually and specifically indicated to be incorporated by reference and set forth in its entirety herein.

[0101] The use of nouns and similar referents in connection with the description of this disclosure (particularly in connection with the claims that follow) shall be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The words "comprise," "have," "include," and "comprise" shall be construed as open-ended terms (i.e., meaning "including, but not limited to"), unless otherwise noted. The recitation of numerical ranges herein is merely intended to serve as a shorthand method for individually referring to each value falling within the range, unless otherwise indicated herein, and each value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or clearly contradicted by context. Any example or exemplary language used herein (e.g., "such as"), unless otherwise claimed, is intended merely to better illustrate the disclosure and does not pose a limitation on the scope of the disclosure. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the present disclosure.

[0102] Preferred embodiments of the disclosure are described herein, including the best mode known to the inventors for carrying out the disclosure. Variations of these preferred embodiments will become apparent to those skilled in the art upon reading the foregoing description. The inventor expects that skilled persons will apply such variations as appropriate, and intends to practice the disclosure otherwise than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, this disclosure includes any combination of the above-described elements in all variations thereof unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims

1. a mold for holding a motor core including a resin-filled portion; a chamber formed in the mold, one end of which communicates with a resin composition filling passage that communicates with the resin filling portion; a plunger that transports the thermosetting resin composition transported to the chamber toward the resin composition filling path; a heater disposed within the mold or within the mold and around the chamber; an extruder that conveys the resin composition to the chamber while kneading it in order to introduce the resin composition into the chamber as a paste-like resin composition; The extruder an extrusion conveying path through which the resin composition is conveyed; a screw disposed in the extrusion conveying path for conveying the resin composition while kneading it; a first temperature control mechanism at least a portion of which is disposed inside the screw; Motor core manufacturing equipment.

2. The extruder further includes a second temperature control mechanism disposed in the extrusion conveying path surrounding a portion of the screw. The motor core manufacturing apparatus according to claim 1 .

3. a step of holding the motor core in a mold in which a resin composition filling passage is formed so that the resin composition filling passage communicates with a resin filling portion of the motor core; a step of using an extruder capable of conveying a resin composition to convey the resin composition toward a chamber communicating with the resin composition filling path while adjusting the temperature of the resin composition, the extruder comprising: an extrusion conveying path through which the resin composition is conveyed; a screw disposed in the extrusion conveying path for conveying the resin composition while kneading it; and a first temperature adjusting mechanism at least a portion of which is disposed inside the screw, and the resin composition introduced into the chamber is a paste-like resin composition; a step of operating a plunger movable within the chamber to fill the softened resin composition in the chamber into the resin filling section; and curing the softened resin composition filled in the resin filled portion. A manufacturing method for a motor core.

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