Manufacturing method for rotary electric machine and rotor for rotary electric machine

Abstract

To enable the formation of bonded magnets with good quality even when the axial length of a rotor core is relatively long.SOLUTION: A manufacturing method for a rotary electric machine includes a step for preparing a first core and a second core, each having an axial center and a magnet placement hole, a first setting step for setting the first core against a mold apparatus, a first filling step for filling a material for injection molding, containing magnetic powder, into the magnet placement hole of the first core after the first setting step, a second setting step for setting the second core adjacent to the first core in the axial direction against the mold apparatus as well as the first core after the first filling step, and a second filling step for filling the magnet placement hole of the second core with the material for injection molding after the second setting step.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing a rotor for a rotating electric machine and a rotor for a rotating electric machine. [Background technology]

[0002] A known technique is to injection mold a material for a bonded magnet, which is a mixture of a magnetic material (magnetic powder) and a non-magnetic resin material (binder), into magnet placement holes in a rotor core. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-147142 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if the axial length of the rotor core becomes relatively long, the axial length (flow length) when injection molding the bonded magnet becomes correspondingly long, making it difficult to form the bonded magnet.

[0005] Therefore, in one aspect, an object of the present disclosure is to make it possible to form a bonded magnet with good quality even when the axial length of the rotor core is relatively long. [Means for solving the problem]

[0006] In one aspect, the method includes: preparing a first core and a second core, each having an axis and a magnet placement hole; a first setting step of setting the first core in a mold device; a first filling step of filling the magnet placement hole of the first core with an injection molding material containing magnetic powder after the first setting step; a second setting step of setting the second core together with the first core in the mold device in a state in which the second core is adjacent to the first core in the axial direction after the first filling step; There is provided a method for manufacturing a rotor for a rotating electric machine, which includes, after the second setting step, a second filling step of filling the magnet arrangement hole of the second core with the injection molding material. [Effects of the Invention]

[0007] In one aspect, the present disclosure makes it possible to form a bonded magnet with good quality even when the axial length of the rotor core is relatively long. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram showing a manufacturing apparatus for a rotor for a rotating electric machine according to a first embodiment. [Figure 2] 3 is a schematic flowchart showing the flow of a method for manufacturing a rotor for a rotating electric machine according to the first embodiment. [Figure 3] FIG. 2 is an explanatory diagram of a step (S200) in the manufacturing method of the first embodiment. [Figure 4] FIG. 2 is an explanatory diagram of a step (S201) in the manufacturing method of the first embodiment. [Figure 5] FIG. 2 is an explanatory diagram of a step (S202) in the manufacturing method of the first embodiment. [Figure 6] FIG. 2 is an explanatory diagram of a step (S203) in the manufacturing method of Example 1. [Figure 7] FIG. 2 is an explanatory diagram of a step (S204) in the manufacturing method of the first embodiment. [Figure 8] FIG. 2 is an explanatory diagram of a step (S205) in the manufacturing method of Example 1. [Figure 9] FIG. 2 is an explanatory diagram of a slide spacer according to the first embodiment. [Figure 10] 10A and 10B are explanatory diagrams of another variation of the slide spacer of the first embodiment. [Figure 11] FIG. 2 is an explanatory diagram of a step (S206) in the manufacturing method of Example 1. [Figure 12]FIG. 2 is an explanatory diagram of a step (S207) in the manufacturing method of Example 1. [Figure 13] FIG. 2 is an explanatory diagram of a step (S208) in the manufacturing method of Example 1. [Figure 14] FIG. 2 is an explanatory diagram of a step (S209) in the manufacturing method of Example 1. [Figure 15] FIG. 2 is an explanatory diagram of a step (S210) in the manufacturing method of Example 1. [Figure 16] FIG. 2 is an explanatory diagram of a step (S211) in the manufacturing method of Example 1. [Figure 17] FIG. 2 is an explanatory diagram of an initialization step in the manufacturing method of the first embodiment. [Figure 18] FIG. 10 is a schematic view showing a manufacturing apparatus for a rotor for a rotating electric machine according to a second embodiment. [Figure 19] FIG. 19 is an explanatory diagram of a modification of the second embodiment, and is a diagram schematically showing a cross section similar to that of FIG. [Figure 20] 10 is an explanatory diagram of a movable spacer according to a second embodiment, showing the movement (various states) of the movable spacer as viewed in the axial direction. FIG. [Figure 21] 10A and 10B are explanatory diagrams illustrating the movement of a robot hand relative to a movable spacer according to the second embodiment, and also explanatory diagrams illustrating other modified examples of the movable spacer. [Figure 22] FIG. 10 is an explanatory view showing another modified example of the movable spacer according to the second embodiment. [Figure 23] 10 is a schematic flowchart showing the flow of a method for manufacturing a rotor for a rotating electric machine according to a second embodiment. [Figure 24] FIG. 10 is an explanatory diagram of a step (S301) in the manufacturing method of Example 2. [Figure 25] FIG. 10 is a diagram showing the gripping posture of the robot hand of the second embodiment. [Figure 26] FIG. 10 is an explanatory diagram of a step (S302) in the manufacturing method of Example 2. [Figure 27] FIG. 10 is an explanatory diagram of a step (S303) in the manufacturing method of Example 2. [Figure 28] FIG. 10 is an explanatory diagram of a step (S304) in the manufacturing method of Example 2. [Figure 29]FIG. 10 is an explanatory diagram of a step (S305) in the manufacturing method of Example 2. [Figure 30] FIG. 10 is an explanatory diagram of a step (S306) in the manufacturing method of Example 2. [Figure 31] FIG. 10 is an explanatory diagram of a step (S307) in the manufacturing method of Example 2. [Figure 32] FIG. 10 is a further explanatory view of step (S307) in the manufacturing method of Example 2. [Figure 33] FIG. 10 is an explanatory diagram of a step (S308) in the manufacturing method of Example 2. [Figure 34] FIG. 10 is an explanatory diagram of a step (S309) in the manufacturing method of Example 2. [Figure 35] FIG. 10 is an explanatory diagram of a step (S310) in the manufacturing method of Example 2. [Figure 36] FIG. 10 is a further explanatory view of step (S310) in the manufacturing method of Example 2. [Figure 37] FIG. 10 is an explanatory diagram of a step (S311) in the manufacturing method of Example 2. [Figure 38] FIG. 10 is an explanatory diagram of a step (S312) in the manufacturing method of Example 2. [Figure 39] FIG. 10 is an explanatory diagram of a step (S313) in the manufacturing method of Example 2. [Figure 40] FIG. 10 is an explanatory diagram of step (S314) in the manufacturing method of Example 2. [Figure 41] FIG. 10 is an explanatory diagram of a step (S315) in the manufacturing method of Example 2. [Figure 42] FIG. 2 is a schematic cross-sectional view of a rotor core including a bonded magnet. DETAILED DESCRIPTION OF THE INVENTION

[0009] Each embodiment will be described in detail below with reference to the accompanying drawings. Note that the dimensional ratios in the drawings are merely examples and are not limiting. Furthermore, shapes and the like in the drawings may be partially exaggerated for the sake of explanation. Furthermore, in the drawings, for ease of viewing, reference symbols may be assigned only to some of the parts that exist with the same attribute.

[0010] In the following, the two embodiments will be broadly referred to as embodiment 1 and embodiment 2, and will be described in order starting from embodiment 1.

[0011] [Example 1] Fig. 1 is a schematic diagram showing a manufacturing apparatus 1 for a rotor for a rotating electric machine according to Example 1. In Fig. 1, the manufacturing apparatus 1 for a rotor for a rotating electric machine is shown in a cross-sectional view taken along a plane passing through a central axis I0. However, an injection molding machine 30 is shown schematically in the form of a block diagram.

[0012] Figure 1 (and subsequent Figures 2 and the like) shows three orthogonal axes in a right-handed coordinate system. In the following description, directions may be represented using this three-axis notation as appropriate. In the following description, the Z direction is the up-down direction, with the positive side of the Z direction being the upper side. The XY plane is the horizontal plane. The X direction is the direction parallel to the central axis I0 and is also referred to as the axial direction. The terms radial direction and circumferential direction correspond to the radial direction and circumferential direction of a cylinder when the cylinder is assumed to have the central axis I0 as its central axis.

[0013] The manufacturing apparatus 1 for a rotor for a rotating electric machine includes a mold device 20, an injection molding machine 30, and a robot hand 40.

[0014] The mold device 20 includes a movable mold 21, a fixed mold 22, an aligning magnetic field applying device 23, a centering mechanism 24, an ejector pin 26, a movable spacer 27, and a slide spacer 28.

[0015] The movable mold 21 and the fixed mold 22 can be opened and closed in the X direction. In a modified example, a mold device that can be opened and closed in the vertical direction may be used.

[0016] The fixed mold 22 may have a gate and a runner for injection molding built in. In this case, the fixed mold 22 forms an injection molding device together with an injection molding machine 30, which will be described later.

[0017] The aligning magnetic field application device 23 acts on the bonded magnet material injected into the magnet placement holes of the rotor core by an injection molding device. The aligning magnetic field application device 23 can apply an aligning magnetic field to the set rotor core workpiece W (described later). The aligning magnetic field acts on the bonded magnet material injected in the injection molding process described later. In other words, the aligning magnetic field aligns the magnetic components in the bonded magnet material, allowing the hardened bonded magnet material to function as a permanent magnet (bonded magnet). Here, the axial length of the effective area of ​​the aligning magnetic field applied by the aligning magnetic field application device 23 is assumed to be the same as the axial length L of the aligning magnetic field application device 23 in the figure. The aligning magnetic field application device 23 is arranged around the central axis I0. The aligning magnetic field application device 23 may be provided integrally with the movable mold 21. In other words, the movable mold 21 may support the aligning magnetic field application device 23 in a manner that allows it to move integrally with the aligning magnetic field application device 23.

[0018] The centering mechanism 24 has the function of centering the workpiece W (described later) with respect to the central axis I0. The centering mechanism 24 may be cylindrical in shape with an outer diameter corresponding to the axial hole (described later) of the workpiece W. In this case, the centering mechanism 24 can center the workpiece W with respect to the central axis I0 by passing through the axial hole of the workpiece W. The centering mechanism 24 may be provided integrally with the movable mold 21. In other words, the movable mold 21 may support the centering mechanism 24 in a manner that allows it to move integrally with the centering mechanism 24.

[0019] The ejector pin 26 may be a mechanism that is originally provided in the mold device 20. The ejector pin 26 is movable in the axial direction relative to the movable mold 21. The ejector pin 26 functions when removing the workpiece W from the movable mold 21, etc.

[0020] The movable spacer 27 functions as an axial spacer. When the movable spacer 27 is centered by the centering mechanism 24, it is movable in the axial direction relative to the centering mechanism 24 (and therefore the movable mold 21). The movable spacer 27 may have an annular shape when viewed in the axial direction. The function of the movable spacer 27 will be described later in connection with the description of the manufacturing method to be described later.

[0021] The slide spacer 28 functions as an axial spacer, similar to the movable spacer 27. The slide spacer 28 is disposed at a position outside the axial range of the aligning magnetic field application device 23. The slide spacer 28 is movable in the radial direction relative to the movable mold 21. The slide spacer 28 may be fixed in the axial direction relative to the movable mold 21. The function of the slide spacer 28 will be described later in connection with the description of the manufacturing method to be described later.

[0022] Next, a method for manufacturing a rotor for a rotating electric machine according to this embodiment using the manufacturing apparatus 1 for a rotor for a rotating electric machine will be described with reference to FIGS.

[0023] Fig. 2 is a schematic flowchart showing the flow of the manufacturing method for a rotor for a rotating electric machine according to this embodiment. Figs. 3 to 17 are explanatory diagrams of each state in this manufacturing method, with Fig. 3 being a side view of the workpiece W, Figs. 4 to 8 and Figs. 11 to 17 being side views similar to Fig. 1 showing the relationship between the manufacturing apparatus 1 for a rotor for a rotating electric machine and the workpiece W, and Fig. 9 being an explanatory diagram of a slide spacer 28, showing two states (positions) of the slide spacer 28 as viewed in the axial direction. Fig. 10 is a diagram showing another variation of the slide spacer 28.

[0024] This manufacturing method first includes a step (step S200) of preparing two workpieces W for forming one rotor core. In this embodiment, one rotor core 320 (see FIG. 42) is formed by axially joining two core portions (described later). The two workpieces W correspond to the two core portions. Hereinafter, when distinguishing between the two workpieces W, they will be referred to as half cores W1 and W2. The half cores W1 and W2 are assumed to have the same configuration, but in modified examples, they may be different (for example, they may have different axial lengths). FIG. 3 shows an example of a workpiece W in cross section. The workpiece W has an axial hole 324W corresponding to the axial hole 324 (see FIG. 42) of the rotor core 320 and a magnet arrangement hole 322W corresponding to the magnet arrangement hole 322 (see FIG. 42) of the rotor core 320.

[0025] Next, this manufacturing method includes a step (step S201) of setting the first half core W1 in the mold device 20. FIG. 4 illustrates this step in chronological order from top to bottom. The half core W1 is grasped by the robot hand 40 (ST41) and transferred to the mold device 20 (see arrow R41). The half core W1 is then set in the mold device 20 in a manner to be centered by the centering mechanism 24 (ST42). That is, the robot hand 40 pushes the half core W1 toward the negative side in the X direction (see arrow R42), thereby centering the half core W1 with the center axis I0 of the centering mechanism 24 aligned with the center axis I1 of the half core W1. At this time, the half core W1 is set in the mold device 20 without a bond magnet formed in the magnet placement hole 322W (i.e., the magnet placement hole 322W is empty). Thereafter, the robot hand 40 releases the half core W1 and then retreats in a direction away from the movable die 21 (see arrow R43) (ST43).

[0026] Next, this manufacturing method includes a step (step S202) of forming the mold device 20 in a mold closed state with the first half core W1 set in place. In this case, the movable mold 21 moves in the positive X direction (see arrows R51 to R53), thereby forming a mold closed state (ST53) from the mold open state (ST51 in FIG. 5) via an intermediate state ST52. In the mold closed state (ST53), the half core W1 is sandwiched in the axial direction between the movable mold 21 and the fixed mold 22 via the movable spacer 27 and the slide spacer 28.

[0027] Next, this manufacturing method includes a bond magnet molding process (step S203) for the first half core W1. The bond magnet molding process may be performed with a clamping force applied. In this process, a bond magnet material (hereinafter simply referred to as "bond magnet material"), a mixture of magnetic powder and a binder, is injection-molded using an injection molding machine 30 and a gate in the fixed mold 22. The injection molding method may be any method, including transfer molding or resin injection by compression molding using a cylinder. The runner may also be any method, such as a cold runner or hot runner. The bond magnet material is filled into the magnet placement hole 322W of the half core W1. FIG. 6 shows the bond magnet material 71 filled into the half core W1 (see arrow R60). The bond magnet material 71 may include, for example, a thermoplastic resin material, and gradually hardens once filled into the magnet placement hole 322W of the half core W1.

[0028] The bond magnet molding process (step S203) for the first half core W1 is performed in a state where an aligning magnetic field is formed by the aligning magnetic field application device 23. During the bond magnet molding process (step S203) for the first half core W1, the first half core W1 is positioned within the aligning magnetic field of the aligning magnetic field application device 23. In other words, the half core W1 is placed within a space surrounded by the aligning magnetic field application device 23 (a cylindrical space with a length L).

[0029] Next, this manufacturing method includes a step of forming an open mold state (step S204). The open mold state is realized by moving the movable mold 21 together with the half core W1 filled with the bonded magnet material 71 toward the negative side in the X direction, as shown by arrow R7 in FIG.

[0030] In this embodiment, this step (step S204) is preferably performed promptly after the bond magnet molding step (step S203) for the first half core W1. In other words, this step (step S204) is preferably performed before the bond magnet material 71 hardens. This minimizes the time between the bond magnet molding step (step S203) for the first half core W1 and the subsequent bond magnet molding step (step S208) for the second half core W2. The technical significance of this will be described later in relation to the bond magnet molding step (step S208) for the second half core W2.

[0031] Next, this manufacturing method includes a step (step S205) of moving the slide spacer 28 to a retracted position radially outward. This step is achieved by sliding the slide spacer 28 to the retracted position radially outward (e.g., vertically) as indicated by arrow R8 in FIG. 8 . The movement of the slide spacer 28 may be achieved by an actuator or a robot hand such as the robot hand 40. In FIG. 9 , the left side shows the slide spacer 28 functioning as a spacer (spacer position), and the right side shows the slide spacer 28 not functioning as a spacer (retracted position). In the example shown in FIG. 9 , the slide spacer 28 has divided sections 281 and 282 that can be separated horizontally when viewed in the axial direction. The divided sections 281 and 282 abut horizontally at the spacer position. In this case, the mating surfaces (abutment surfaces) are the XY plane. However, the mating surfaces are determined depending on the sliding direction and may be any surface that includes the axial direction. The divided portions 281, 282 have a circular shape when viewed in the axial direction when mated. When mated, the divided portions 281, 282 form an axial hole 284 through which the centering mechanism 24 passes. The slide spacer 28 may further have an engagement means for engaging the divided portions 281, 282. As shown in FIG. 9, the engagement means may be a fitting means between a horizontal convex portion 2811 and a concave portion (or hole) 2822. The divided portions 281, 282 can be moved away from each other to change their state, moving from the spacer position to the retracted position (see arrow R9). Furthermore, the divided portions 281, 282 can be moved toward each other to change their state, moving from the retracted position to the spacer position. Note that the structure of the slide spacer 28 shown in FIG. 9 is merely an example, and various modifications are possible. For example, divided portions 281A and 282A that have a non-circular shape when viewed in the axial direction when they are fitted together, such as a slide spacer 28A shown in FIG. 10, may be used.

[0032] Next, this manufacturing method includes a step (step S206) of setting the second half core W2 in the mold apparatus 20. Like the first half core W1, the second half core W2 is set in the mold apparatus 20 without bond magnets formed in the magnet arrangement holes 322W (i.e., the magnet arrangement holes 322W are empty). In this set state, the half cores W1 and W2 are adjacent to each other in the axial direction. The phases of the magnet arrangement holes 322W of the half core W1 and the magnet arrangement holes 322W of the half core W2 are aligned. That is, the magnet arrangement holes 322W of the half core W1 and the magnet arrangement holes 322W of the half core W2 overlap when viewed in the axial direction. In a modified example, a slight offset may be intentionally set between the phases of the magnet arrangement holes 322W of the half core W1 and the magnet arrangement holes 322W of the half core W2. That is, the magnet placement holes 322W of the half core W1 and the magnet placement holes 322W of the half core W2 may partially overlap when viewed in the axial direction. In this case, the magnet placement holes 322W of the half core W1 and the magnet placement holes 322W of the half core W2 may be connected in the axial direction (communicating when the bonded magnetic material 71 is not present). In Figure 11, the movement of the half core W2 from the state in which it is gripped by the robot hand 40 (ST111) to the state in which it is set (ST112) is schematically shown by arrows R111 and R112.

[0033] Next, this manufacturing method includes a step (step S207) of forming a mold closed state of the mold device 20 with the two half cores W2 set in place. The mold closed state can be achieved by moving the movable mold 21, in which the half cores W1 and W2 are set, in the positive X-direction until it mates with the fixed mold 22, as shown by arrow R12 in FIG.

[0034] Next, the manufacturing method includes a bond magnet molding process (step S208) for the second half core W2. This process may be performed in the same manner as the bond magnet molding process (step S203) for the first half core W1 described above. The bond magnet material is filled into the magnet arrangement holes 322W of the half core W2. FIG. 13 shows the bond magnet material 72 filled into the half core W2 (see arrow R13). The bond magnet material 72 is made of the same material as the bond magnet material 71.

[0035] The bond magnet molding process (step S208) for the second half core W2 is preferably performed with the first half core W1 and half core W2 adjacent to each other in the axial direction. Therefore, the bond magnet material 72 can come into contact with the bond magnet material 71 before, during, or after hardening. This allows them to be substantially bonded together when they are (completely) hardened. Even when they come into contact with the hardened bond magnet material 71, the heat from the bond magnet material 72 can cause the bond magnet material 71 to melt due to heat from the end face of the hardened bond magnet material 71 (the end face that contacts the bond magnet material 72). Therefore, even when the bond magnet material 71 melts in this way, they will be substantially bonded together when they are hardened. Hereinafter, the half cores W1 and W2 connected in this way via the bond magnet material 71 and bond magnet material 72 will also be referred to as the "integrated core of the two half cores W1 and W2."

[0036] The bond magnet molding process (step S208) for the second half core W2 is performed with the aligning magnetic field formed by the aligning magnetic field application device 23. During the bond magnet molding process (step S208) for the second half core W2, the second half core W2 is positioned within the aligning magnetic field of the aligning magnetic field application device 23. In this embodiment, even though the axial length L of the aligning magnetic field application device 23 is shorter than the axial length of the integrated core of the two half cores W1 and W2, the second half core W2 can be positioned within the aligning magnetic field of the aligning magnetic field application device 23. This is because, by moving the slide spacer 28 to the retracted position, the half core W1 can be moved axially outward from the aligning magnetic field space (toward the movable mold 21) by the axial length of the slide spacer 28. In this case, the axial size of the aligning magnetic field application device 23 (and therefore the rotating electric machine rotor manufacturing apparatus 1) can be reduced.

[0037] Next, this manufacturing method includes a step of achieving a mold open state (step S209). The mold open state is achieved by moving the movable mold 21 together with the integrated core of the two half cores W1 and W2 toward the negative side in the X direction, as shown by arrow R14 in FIG.

[0038] Next, this manufacturing method includes a step (step S210) of pushing out the integrated core of the two half cores W1 and W2 using the ejector pin 26 (referred to as "EJ pin" in FIG. 2). As a result, at least a part of the integrated core of the two half cores W1 and W2 is pushed out of the movable mold 21, as shown by the arrow R15 in FIG.

[0039] Next, this manufacturing method includes a step (step S211) of removing the integrated core of the two half cores W1 and W2 by the robot hand 40. As shown in Fig. 16, the robot hand 40 approaches the movable die 21 from the positive side in the X direction, as indicated by arrow 161 (arrow R161), and grips the half core W2 (ST161). Then, by moving in a direction away from the movable die 21 (arrow R162), the integrated core of the two half cores W1 and W2 can be removed (ST162).

[0040] Thereafter, as shown by arrows R171 and R172 in Figure 17, the ejector pin 26 returns to its original position and the slide spacer 28 returns to the spacer position, thereby returning the rotating electric machine rotor manufacturing apparatus 1 to a state ready for the next new workpiece W (a state in which the process can begin from step S201).

[0041] Here, as mentioned above, if the axial length of the rotor core becomes relatively long, the axial length (flow length) when injection molding the bonded magnet becomes correspondingly long, making it difficult to form the bonded magnet.

[0042] In this regard, according to this embodiment, the bond magnet material can be injection molded separately for the two half cores W1 and W2 that are arranged axially stacked, so the axial length (flow length) of one workpiece W can be made relatively short.

[0043] However, since bonded magnets (resin components) shrink after molding, if the bonded magnet material is simply injection molded separately for two half cores, cured, and then the two half cores are joined in the axial direction, an axial gap is likely to form between the bonded magnets of the two half cores. The occurrence of such an axial gap leads to a decrease in strength and torque.

[0044] In this regard, according to this embodiment, as described above, the second half core W2 is placed adjacent to the first half core W1 filled with the bonded magnetic material 71, and then the second half core W2 is filled with the bonded magnetic material 72. As a result, even if the bonded magnetic material 71 of the first half core W1 has shrunk or hardened by the time the bonded magnetic material 72 is filled into the second half core W2, the bonded magnetic material 72 filled into the second half core W2 can reach any recesses that may be formed by the shrinkage. As a result, axial gaps are less likely to occur in the integrated core of the two half cores W1 and W2, resulting in a high-quality bonded magnet. This also applies when the first half core W1 is removed and then re-set adjacent to the half core W2 (as in a modified example not shown). In this case, the bonded magnetic material 72 filled into the second half core W2 can reach any recesses, such as gate marks, of the first half core W1. As a result, gaps in the axial direction are less likely to occur in the integrated core of the two half cores W1 and W2, making it possible to form a high-quality bonded magnet.

[0045] In this embodiment, the bond magnet molding process (step S208) for the second half core W2 is preferably performed before the bond magnet material 71 filled in the bond magnet molding process (step S203) for the first half core W1 described above is completely hardened. This promotes bonding between the bond magnet material 71 and the bond magnet material 72, allowing the bond magnet material 71 and the bond magnet material 72 to be bonded more firmly. In other words, the bond magnet of the rotor core 320 can be formed in a manner that substantially no gaps or the like occur at the joint between the axial end face (end face on the positive side of the X direction) of the bond magnet material 71 and the axial end face (end face on the negative side of the X direction) of the bond magnet material 72. Furthermore, the magnetic composition of the bond magnet material 71 and the bond magnet material 72 can be homogenized.

[0046] [Example 2] Next, a second embodiment will be described with reference to Fig. 18 onwards. In the following description of the second embodiment, components that may be similar to those in the first embodiment described above will be given the same reference numerals and descriptions thereof may be omitted.

[0047] FIG. 18 is a schematic diagram showing a manufacturing apparatus 1A for a rotor for a rotating electric machine according to a second embodiment. In FIG. 18, the manufacturing apparatus 1A for a rotor for a rotating electric machine is shown in a cross-sectional view taken along a plane passing through the central axis I0. However, an injection molding machine 30 is shown schematically in the form of a block diagram. FIG. 19 is an explanatory diagram of a modification of the second embodiment, showing a cross-sectional view similar to FIG. 18. FIG. 20 is an explanatory diagram of a movable spacer 27A, showing the movement (various states) of the movable spacer 27A as viewed in the axial direction. FIGS. 21 and 22 are explanatory diagrams of the movement of a robot hand 40 relative to the movable spacer 27A, as well as explanatory diagrams showing other modifications related to the movable spacer.

[0048] The manufacturing apparatus 1A for a rotating electric machine rotor according to this embodiment differs from the manufacturing apparatus 1 for a rotating electric machine rotor according to the first embodiment described above mainly in that the die device 20 is replaced with a die device 20A.

[0049] The mold apparatus 20A according to this embodiment differs from the mold apparatus 20 according to the above-described first embodiment in that the movable mold 21, the fixed mold 22, the aligning magnetic field application device 23, the centering mechanism 24, and the movable spacer 27 are replaced with a movable mold 21A, a fixed mold 22A, an aligning magnetic field application device 23A, a centering mechanism 24A, and a movable spacer 27A. The mold apparatus 20A also differs from the mold apparatus 20 according to the above-described first embodiment in that the slide spacer 28 is omitted and a temporary holder 29A is added.

[0050] In terms of function, the movable mold 21A is the same as the movable mold 21 according to the above-mentioned Example 1, but has only formal differences due to the differences in the other components described above (for example, the presence or absence of the slide spacer 28).

[0051] The fixed mold 22A is also functionally the same as the fixed mold 22 according to the first embodiment described above, but differs in that it has an escape hole 220A for avoiding interference with the temporary holder 29A in the mold closed state. Note that if the temporary holder 29A is configured to be detachable, the escape hole 220A itself may be eliminated.

[0052] In this embodiment, the mold opening and closing direction is preferably horizontal in order to realize the movement (drop) of the movable spacer 27A, which will be described later.

[0053] The aligning magnetic field application device 23A is also functionally the same as the aligning magnetic field application device 23 according to the first embodiment described above, but differs in that the length L of the aligning magnetic field application device 23A is long enough to simultaneously apply an aligning magnetic field to the two half cores W1 and W2. However, as in the manufacturing apparatus 1B for a rotor for a rotating electric machine according to a modified example shown in FIG. 19, an aligning magnetic field application device 23B having an axial length significantly shorter than the total axial length of the two half cores W1 and W2 may be used. In this case, the aligning magnetic field application device 23A (and therefore the manufacturing apparatus 1A for a rotor for a rotating electric machine) can be made smaller in the axial direction.

[0054] The centering mechanism 24A is functionally the same as the centering mechanism 24 of the first embodiment described above, but differs only in form from the centering mechanism 24 due to the differences in the other components described above. Specifically, for example, the centering mechanism 24A differs in that a movable spacer 27A can be supported axially movably instead of the movable spacer 27. The centering mechanism 24A also differs in that it is axially movable together with the ejector pins 26. The centering mechanism 24A also differs in that it has a seat 242A that transmits the mold clamping force to the mold apparatus 20A. The seat 242A may be coupled to the tip of the ejector pin 26.

[0055] The movable spacer 27A is functionally similar to the movable spacer 27 according to the first embodiment described above, but differs in detail: specifically, the movable spacer 27A is removable from the centering mechanism 24A during the manufacturing process.

[0056] In this embodiment, the movable spacer 27A has divided sections 271A and 272A that can be separated horizontally when viewed in the axial direction. The divided sections 271A and 272A can be aligned horizontally, and in this case, the alignment surface is the XZ plane. The divided sections 271A and 272A form an axial hole 274A through which the centering mechanism 24A passes when aligned. The movable spacer 27A also has an engaging member 273A that temporarily engages the divided sections 271A and 272A. When the divided sections 271A and 272A are aligned, the engaging member 273A passes through a hole 2710A that continuously penetrates each of the divided sections 271A and 272A, thereby maintaining the aligned state of the divided sections 271A and 272A. The holes 2710A are provided in pairs, one above the other, sandwiching the centering mechanism 24A. The hole 2710A extends in the Y direction (horizontal direction) within the XY plane. In this case, when the engaging member 273A is removed from the hole 2710A, the divided portions 271A and 272A can move apart from each other in the horizontal direction. The operation of removing the engaging member 273A can be achieved by the robot hand 40 (see FIG. 21).

[0057] Here, when the divided parts 271A and 272A are aligned, the shape of the movable spacer 27A (the shape including the engaging member 273A) as viewed in the axial direction is a shape that fits within a reference circle C21 (see FIG. 21, etc.). In this case, the reference circle C21 is a circle centered on the central axis I0, and corresponds to the shape of a space (a space radially inward of the aligning magnetic field application device 23B) in which the movable spacer 27A can move in the axial direction without interfering with the aligning magnetic field application device 23B.

[0058] Although movable spacer 27A is used here, other movable spacers having the same function as movable spacer 27A may also be used. For example, as shown in the lower part of FIG. 21, in a modified example, engaging device 273A may be formed of two separate pieces, one above the other. In this case, the two pieces may be handled separately by robot hand 40, or two robot hands 40 may be used. Furthermore, engaging device 273A is of a pull-out type, but as shown in FIG. 22, it may be of a type that allows separation of divided portions 271B and 272B by pushing it out (see arrow R22). In FIG. 22, the upper side shows a type in which engaging device 273B is connected at the top and bottom, and the lower side shows a type in which engaging device 273B is separated at the top and bottom (two-piece type).

[0059] Further features of the movable spacer 27A (such as its movement during the manufacturing process) are discussed below in connection with the manufacturing method.

[0060] The temporary holder 29A has a function of temporarily supporting the half core W1 while allowing the movable spacer 27A to be removed from the centering mechanism 24A during the manufacturing process. This feature will be described later in relation to the manufacturing method. In a modified example, the temporary holder 29A may be partially or entirely detachable from the movable mold 21A.

[0061] Next, a method for manufacturing a rotor for a rotating electric machine according to this embodiment using the manufacturing apparatus 1A for a rotor for a rotating electric machine will be described with reference to FIGS.

[0062] Fig. 23 is a schematic flowchart showing the flow of the manufacturing method for a rotor for a rotating electric machine according to this embodiment. Figures 24 and onward are explanatory diagrams of each state in this manufacturing method, and Fig. 24, Fig. 26 to Fig. 31, and Fig. 33 to Fig. 41 are side views similar to Fig. 23 showing the relationship between the manufacturing apparatus 1A for a rotor for a rotating electric machine and the workpiece W, and Fig. 25 is a diagram showing the gripping posture of the robot hand 40. Fig. 32 is an explanatory diagram of the removal process of the movable spacer 27A.

[0063] This manufacturing method first includes a step (step S300) of preparing two workpieces W for forming one rotor core. In this manufacturing method, the two workpieces W are the half cores W1 and W2 described above.

[0064] Next, this manufacturing method includes a step (step S301) of setting the movable spacer 27A in the mold device 20A. That is, while maintaining the movable spacer 27A in the aligned state, a state is created in which the centering mechanism 24A is passed through the axial hole 274A. In the example shown in FIG. 24, in the mold open state (ST241), a state (ST242) is created in which the movable spacer 27A is set by the robot hand 40. Note that in this manufacturing method, the posture (direction) of the robot hand 40 is appropriately rotated as shown in FIG. 25 so that the temporary holder 29A and the robot hand 40 do not interfere with each other. That is, the robot hand 40 operates so that the gripping direction is horizontal. Note that this posture of the robot hand 40 is also the same in the next step (step S302) and the like.

[0065] Next, this manufacturing method includes a step (step S302) of setting the first half core W1 in the mold device 20A. FIG. 26 shows an explanatory diagram of this step in chronological order from top to bottom. The half core W1 is grasped by the robot hand 40 (ST261) and set in the mold device 20A in a manner that allows it to be centered by the centering mechanism 24A (ST262). At this time, the center axis I0 of the centering mechanism 24A and the center axis I1 of the half core W1 are aligned. At this time, the half core W1 is set in the mold device 20A in a state where no bond magnet is formed in the magnet placement hole 322W (i.e., the magnet placement hole 322W is empty).

[0066] Next, this manufacturing method includes a process (step S303) of forming the mold device 20A in a mold closed state with the first half core W1 set in place. In this case, as shown by arrow R27 in Fig. 27, the mold closed state is formed by moving the movable mold 21 in the positive X direction to a position where it mates with the fixed mold 22A.

[0067] Next, this manufacturing method includes a bond magnet molding process (step S304) for the first half core W1. This process may be substantially similar to the bond magnet molding process (step S203) for the first half core W1 according to the above-described Example 1. In Figure 28, the state in which the bond magnet material 71 is filled is schematically shown by arrow R28.

[0068] Next, this manufacturing method includes a step of achieving a mold open state (step S305). The mold open state is achieved by moving the movable mold 21 together with the half core W1 filled with the bonded magnetic material 71 toward the negative side in the X direction, as shown by arrow R29 in Figure 29. In this embodiment, as in the above-described embodiments, this step (step S305) is preferably performed promptly after the bonded magnet molding step (step S304) for the first half core W1.

[0069] Next, this manufacturing method includes a step (step S306) of simultaneously pushing out the half core W1 and the movable spacer 27A using the ejector pin 26. In Figure 30, the manner in which the half core W1 and the movable spacer 27A are pushed out is schematically shown by arrow R30. The half core W1 and the movable spacer 27A may be pushed out until the movable spacer 27A comes outside the movable mold 21. At this time, the half core W1 is supported by the temporary holder 29A.

[0070] Next, this manufacturing method includes a step of removing movable spacer 27A (step S307). Fig. 31 shows the state after movable spacer 27A has been removed. As shown in Fig. 32, by using robot hand 40 to pull out engaging member 273A from state ST321, movable spacer 27A becomes split as shown in ST323 when viewed in the axial direction, and split portions 271A and 272A fall from temporary holder 29A due to gravity.

[0071] Next, the manufacturing method includes a step (step S308) of removing the movable spacer 27A and using the axial space created by the removal of the movable spacer 27A to push the half core W1 toward the negative side in the X direction. In the example shown in Fig. 33, the half core W1 is pushed toward the negative side in the X direction using the robot hand 40.

[0072] Next, this manufacturing method includes a step (step S309) of retracting the ejector pin 26 and the centering mechanism 24A (moving them toward the negative side in the X direction). FIG. 34 shows the state after retraction. In this manufacturing method, as shown by arrow R34 in FIG. 34, the ejector pin 26 and the centering mechanism 24A are retracted to a degree that prevents the half core W1 from coming out of the centering mechanism 24A. In other words, the axial length of the centering mechanism 24A may be adjusted in this step (step S309) so that the centering mechanism 24A can return to a position where the seat portion 242A abuts against the movable mold 21A in the axial direction while holding the half core W1 in a centered state.

[0073] Next, this manufacturing method includes a step (step S310) of setting the second half core W2 in the mold apparatus 20A. In FIG. 35, the arrow R35 also indicates the manner in which the half core W2 is set using the robot hand 40. Like the first half core W1, the second half core W2 is set in the mold apparatus 20A without bonded magnets formed in the magnet arrangement holes 322W (i.e., the magnet arrangement holes 322W are empty). In this set state, the half cores W1 and W2 are adjacent to each other in the axial direction. Furthermore, the phases of the magnet arrangement holes 322W of the half core W1 and the magnet arrangement holes 322W of the half core W2 are aligned. That is, the magnet arrangement holes 322W of the half core W1 and the magnet arrangement holes 322W of the half core W2 are connected in the axial direction. In a modified example, a slight offset may be intentionally set between the phase of each magnet arrangement hole 322W of half core W1 and the phase of each magnet arrangement hole 322W of half core W2. In this case, each magnet arrangement hole 322W of half core W1 and each magnet arrangement hole 322W of half core W2 may be connected in the axial direction.

[0074] In this manufacturing method, the process of setting the second half core W2 in the mold device 20A (step S310) may include pushing the half core W2 together with the half core W1 until the half core W2 is centered by the centering mechanism 24A, as shown in Figure 36.

[0075] Next, this manufacturing method includes a step (step S311) of forming the mold device 20A in a mold closed state with the two half cores W2 set in place. The mold closed state can be achieved by moving the movable mold 21A, in which the half cores W1 and W2 are set, in the positive X-direction until it mates with the fixed mold 22A, as shown by arrow R37 in Figure 37.

[0076] Next, the manufacturing method includes a bond magnet molding process (step S312) for the second half core W2. This process may be substantially similar to the bond magnet molding process (step S208) for the second half core W2 according to the above-described Example 1. In Figure 38, the state in which the bond magnet material 72 is filled is schematically shown by arrow R38.

[0077] Next, this manufacturing method includes a step of achieving a mold open state (step S313). The mold open state is achieved by moving the movable mold 21A together with the integrated core of the two half cores W1 and W2 toward the negative side in the X direction, as shown by arrow R39 in FIG.

[0078] Next, this manufacturing method includes a step (step S314) of pushing out the integrated core of the two half cores W1 and W2 using the ejector pin 26 (referred to as "EJ pin" in FIG. 23). As a result, at least a part of the integrated core of the two half cores W1 and W2 is pushed out of the movable mold 21A as shown by the arrow R40 in FIG.

[0079] Next, this manufacturing method includes a step (step S315) of removing the integrated core of the two half cores W1 and W2 by the robot hand 40. In the example shown in FIG. 41, the integrated core of the two half cores W1 and W2 is removed by the robot hand 40.

[0080] This manufacturing method also provides the same effects as the manufacturing method according to the first embodiment described above.

[0081] Finally, with reference to FIG. 42, a characteristic configuration of the rotor core 320 manufactured by the manufacturing method of the first or second embodiment will be described.

[0082] FIG. 42 is a schematic cross-sectional view of a rotor core 320 equipped with a bonded magnet 70. In this embodiment, the rotor core 320 equipped with the bonded magnet 70 is manufactured by the manufacturing method described above. As described above, the bonded magnet 70 is formed by filling the bonded magnet material 72 into the half core W2 with the half cores W1 and W2 adjacent to each other in the axial direction. This ensures that there are virtually no gaps or the like at the joint 80. In this way, according to this embodiment, good quality of the bonded magnet 70 can be ensured even if the axial length of the rotor core 320 is relatively long.

[0083] Although each embodiment has been described in detail above, it is not limited to the specific embodiment, and various modifications and changes are possible within the scope of the claims. It is also possible to combine all or a plurality of components of the above-described embodiments.

[0084] For example, in the above-described embodiment, the rotor core 320 is formed using half cores W1 and W2, but the manufacturing method according to the above-described embodiment can also be used when forming a rotor core by connecting three or more cores in the axial direction.

[0085] In addition to the above disclosure, the following is further disclosed.

[0086] [Appendix 1] preparing a first core and a second core each having an axis and a magnet placement hole; a first setting step of setting the first core in a mold device; a first filling step of filling the magnet placement hole of the first core with an injection molding material containing magnetic powder after the first setting step; a second setting step of setting the second core together with the first core in the mold device in a state in which the second core is adjacent to the first core in the axial direction after the first filling step; a second filling step of filling the magnet placement hole of the second core with the injection molding material after the second setting step.

[0087] [Appendix 2] 2. The method for manufacturing a rotor for a rotating electric machine according to claim 1, wherein the second filling step is performed before the injection molding material filled in the first core is completely hardened.

[0088] [Appendix 3] the die device includes a centering mechanism that forms a centered state of the first core and the second core based on axial holes related to the axial centers of the first core and the second core, A rotor manufacturing method for a rotating electric machine as described in Appendix 1 or 2, wherein the first filling process and the second filling process are performed using the same centering mechanism, and the first core is maintained in a centered state by the centering mechanism even after the first filling process.

[0089] [Appendix 4] the die assembly includes an axial spacer; 4. The method for manufacturing a rotor for a rotating electric machine according to claim 1, wherein the first filling step is performed with the spacer axially adjacent to the first core.

[0090] [Appendix 5] 5. The manufacturing method of a rotor for a rotating electric machine according to claim 4, wherein the second setting step includes retracting the spacer to a retracted position where the spacer does not overlap the first core when viewed in the axial direction.

[0091] [Appendix 6] the mold device includes an orientation device capable of forming an orientation magnetic field; the axial length of an effective region of the aligning magnetic field is shorter than the sum of the axial length of the first core and the axial length of the second core, the first filling step is performed in a state in which the first core is included in an axial range of an effective region of the aligning magnetic field, A method for manufacturing a rotor for a rotating electric machine described in any one of Appendix 1 to 5, wherein the second filling process is performed in a state in which the second core is included in the axial range of the effective area of ​​the aligning magnetic field.

[0092] [Appendix 7] 7. The method for manufacturing a rotor for a rotating electric machine according to claim 1, wherein the second filling step includes bringing the injection molding material filled in the first core into contact with the injection molding material to be filled in the magnet arrangement hole of the second core. [Explanation of symbols]

[0093] W1···Half core (first core), W2···Half core (second core), 322W···Magnet placement hole, 324W···Axial hole (axial center), 20, 20A···Molding device, 23, 23B···Alignment magnetic field application device (alignment device), 320···Rotor core (core), 70···Bonded magnet (permanent magnet), 322···Magnet placement hole

Claims

1. preparing a first core and a second core each having an axis and a magnet placement hole; a first setting step of setting the first core in a mold device; a first filling step of filling the magnet placement hole of the first core with an injection molding material containing magnetic powder after the first setting step; a second setting step of setting the second core together with the first core in the mold device in an axially adjacent manner to the first core after the first filling step; a second filling step of filling the magnet placement hole of the second core with the injection molding material after the second setting step.

2. 2. The method for manufacturing a rotor for a rotating electric machine according to claim 1, wherein the second filling step is performed before the injection molding material filled in the first core is completely hardened.

3. 3. The rotor manufacturing method for a rotating electric machine according to claim 1, wherein the second setting process includes axially adjacent the second core to the first core in such a manner that the magnet placement hole of the second core partially overlaps the magnet placement hole of the first core when viewed in the axial direction.

4. 3. The rotor manufacturing method for a rotating electric machine according to claim 1, wherein the second setting process includes axially adjacently positioning the second core to the first core in such a manner that the magnet placement holes of the first core overlap the magnet placement holes of the second core in an axial view.

5. the mold device includes an orientation device capable of forming an orientation magnetic field; the axial length of an effective region of the aligning magnetic field is shorter than the sum of the axial length of the first core and the axial length of the second core, the first filling step is performed in a state in which the first core is included in an axial range of an effective region of the aligning magnetic field, 4. The method for manufacturing a rotor for a rotating electric machine according to claim 3, wherein the second filling step is performed in a state in which the second core is included in an axial range of an effective region of the aligning magnetic field.

6. a core having an axis and a magnet arrangement hole; a permanent magnet disposed in the magnet disposition hole, the permanent magnet comprises a cured product of an injection molding material containing a magnetic powder; The hardened product has a joint portion aligned in the axial direction at a position axially inward of the axial end portion within the magnet placement hole.

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