Rotor manufacturing method, rotor, drive unit, and end plate
The method addresses inefficient magnet cooling in rotors by using end plates with slits and protrusions to create a direct cooling path, improving thermal management and reducing resin dependency.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2022-11-14
- Publication Date
- 2026-05-19
AI Technical Summary
Existing rotors face inefficiencies in cooling magnets due to resin surrounding the magnet insertion holes, hindering effective heat dissipation.
A method involving a rotor core sandwiched between end plates with slits and protrusions that allow for direct contact between the magnet and a cooling medium, forming a continuous gap for efficient cooling.
The method enables efficient cooling of magnets by allowing direct contact with a cooling medium, reducing thermal demagnetization and eliminating the need for high-temperature resin fixation, thus enhancing rotor performance.
Smart Images
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Abstract
Description
Technical Field
[0001] The present disclosure relates to a method for manufacturing a rotor, a rotor, a drive device, and an end plate.
Background Art
[0002] For example, a rotor is configured such that a rotor core formed of a plurality of electromagnetic steel sheets is sandwiched between end plates to fix the electromagnetic steel sheets. For example, in Patent Document 1, an end plate is arranged to sandwich a rotor core, a magnet is inserted into a magnet insertion hole of the rotor core through a magnet insertion hole formed in one of the end plates, and then the magnet insertion hole of the end plate is closed with a non-magnetic material such as resin for manufacturing.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] The applicant of the present application has found the following problems. A general rotor is configured such that a magnet is fixed to a rotor core by resin injected into a magnet insertion hole of the rotor core. Therefore, there is a problem that the magnet inserted into the magnet insertion hole of the rotor core is surrounded by resin and the magnet cannot be efficiently cooled.
[0005] The present disclosure has been made in view of such problems, and realizes a method for manufacturing a rotor, a rotor, a drive device, and an end plate capable of efficiently cooling a magnet inserted into a magnet insertion hole of a rotor core.
Means for Solving the Problems
[0006] A method for manufacturing a rotor according to one aspect of the present disclosure is a method for manufacturing a rotor in which a rotor core made of laminated electromagnetic steel sheets is sandwiched between a first end plate and a second end plate, The first end plate, which has a slit formed in it, is fixed to one end of the rotor core in the axial direction, and the magnet insertion hole of the rotor core and the slit of the first end plate are made continuous. The steps include fixing the second end plate to the other axial end of the rotor core, The process involves sandwiching and fixing a magnet inserted into the magnet insertion hole of the rotor core between a protrusion formed on the first end plate at a position overlapping with the magnet in the axial direction of the rotor core, and the second end plate. It is equipped with.
[0007] In the rotor manufacturing method described above, when inserting the magnet into the magnet insertion hole of the rotor core, the cover portion located inside the C-shaped slit of the first end plate is bent to form a magnet insertion hole in the first end plate, and the magnet insertion hole of the rotor core is exposed, and the magnet is inserted into the magnet insertion hole of the rotor core through the magnet insertion hole of the first end plate. When fixing the magnet, it is preferable to bend the cover portion of the first end plate back to cover the magnet insertion hole of the rotor with the cover portion and to bring the protrusion formed on the cover portion of the first end plate into contact with the magnet.
[0008] In the rotor manufacturing method described above, the cover portion of the first end plate is bent or unbent along a predetermined bending line. The convex portion is preferably formed so as to straddle the bending line.
[0009] In the rotor manufacturing method described above, it is preferable to fix the first end plate, which has the protrusions formed on it in advance, to one end of the rotor core in the axial direction.
[0010] The above-mentioned method for manufacturing the rotor is: A step of measuring the value of a preset measurement parameter when a voltage is applied between the first end plate and the second end plate after fixing the magnet, A step of adjusting the amount of bending back of the cover portion of the first end plate so that the value of the measurement parameter becomes smaller than a preset threshold, It is preferable to include the following.
[0011] A rotor according to one aspect of the present disclosure is a rotor in which a rotor core made of laminated electromagnetic steel sheets is sandwiched between a first end plate and a second end plate, The first end plate is, The rotor core has a slit that is continuous with the magnet insertion hole, A convex portion is formed in the first end plate in the axial direction of the rotor core, at a position that overlaps with the magnet inserted into the magnet insertion hole of the rotor core, and protrudes toward the magnet, Equipped with, The magnet is sandwiched and fixed between the protrusion of the first end plate and the second end plate. A gap is formed between the magnet insertion portion of the rotor core and the magnet.
[0012] In the rotor described above, the slit is C-shaped, Preferably, the protrusions are positioned so as to straddle the line connecting the ends on the opening side of the slit.
[0013] In the rotor described above, it is preferable that the second end plate has a slit that is continuous with the magnet insertion hole of the rotor core.
[0014] In the rotor described above, the second end plate is formed at a position on the second end plate that overlaps with the magnet in the axial direction of the rotor core, and has a protrusion that protrudes toward the magnet. It is preferable that the magnet is sandwiched and fixed between the convex portions of the first end plate and the convex portions of the second end plate.
[0015] A drive device according to an aspect of the present disclosure includes a motor including the above-described rotor, a housing that houses the motor, a cooling medium supplied inside the housing, and is provided with.
[0016] An end plate according to an aspect of the present disclosure is an end plate used to sandwich a rotor core in which electromagnetic steel sheets are laminated, and includes a slit continuous with the magnet insertion hole of the rotor core in a state where the end plate is fixed to an axial end of the rotor core.
[0017] The above-described end plate is formed at a position overlapping with a magnet inserted into the magnet insertion hole of the rotor core in the axial direction of the rotor core in the end plate in a state where the end plate is fixed to an axial end of the rotor core, and preferably includes a convex portion protruding toward the side of the magnet.
Effects of the Invention
[0018] According to the present disclosure, it is possible to realize a method for manufacturing a rotor, a rotor, a drive device, and an end plate that can efficiently cool a magnet inserted into a magnet insertion hole of a rotor core.
Brief Description of the Drawings
[0019] [Figure 1] It is a diagram showing the configuration of a drive device according to an embodiment. [Figure 2] It is a cross-sectional view showing a rotor according to an embodiment. [Figure 3] In the rotor according to the embodiment, it is a view seen from the + side of the Y axis in a state where a magnet is covered by a covering portion of a first end plate. [Figure 4]This is a cross-sectional view showing the state in which the magnet is covered by the cover portion of the first end plate in the rotor of the embodiment. [Figure 5] This diagram shows the protrusion of the first end plate. [Figure 6] This is a view from the Y-axis side of the rotor according to the embodiment, showing the magnet covered by the cover portion of the second end plate. [Figure 7] This is a cross-sectional view showing the state in which the magnet is covered by the cover portion of the second end plate in the rotor of the embodiment. [Figure 8] This is a cross-sectional view showing the rotor core with the first end plate fixed to it. [Figure 9] This is a view from the Y-axis + side showing the rotor core with the first end plate fixed to it. [Figure 10] This is a cross-sectional view showing the first end plate with the cover portion folded. [Figure 11] This is a view from the Y-axis+ side of the first end plate with the cover portion folded. [Figure 12] This is a cross-sectional view showing the rotor core with magnets inserted into the magnet insertion holes. [Figure 13] This diagram shows the rotor core with magnets inserted into the magnet insertion holes, viewed from the Y-axis + side. [Figure 14] This diagram shows the configuration of a control system for adjusting the amount of bending back of the cover portion of the first end plate. [Figure 15] This is a view from the Y-axis+ side of a rotor in a different embodiment, showing the magnet covered by the cover portion of the first end plate. [Figure 16] This is a cross-sectional view showing a rotor of a different embodiment in which the magnet is covered by the cover portion of the first end plate. [Modes for carrying out the invention]
[0020] The following describes specific embodiments applying this disclosure in detail with reference to the drawings. However, this disclosure is not limited to the following embodiments. Also, for clarity, the explanation will be given using a three-dimensional (XYZ) coordinate system, and the following description and drawings have been simplified as appropriate.
[0021] First, the configuration of the drive unit of this embodiment will be described. Figure 1 is a diagram showing the configuration of the drive unit of this embodiment. As shown in Figure 1, the drive unit 1 of this embodiment comprises a motor 2, a housing 3, and a cooling medium 4.
[0022] As shown in Figure 1, the motor 2 comprises a stator 5 and a rotor 6. The stator 5 comprises a stator core 7 in which substantially annular electromagnetic steel sheets, substantially parallel to the XZ plane, are stacked in the Y-axis direction, and a coil 8 wound around the stator core 7.
[0023] Figure 2 is a cross-sectional view showing the rotor of this embodiment. As shown in Figure 2, the rotor 6 comprises a rotor core 9, a shaft 10, a magnet 11, a first end plate 12, and a second end plate 13. As shown in Figure 1, the rotor 6 is passed through a through hole 7a formed in the stator core 7 of the stator 5.
[0024] As shown in Figure 2, the rotor core 9 is made up of substantially annular electromagnetic steel sheets 9a stacked in the Y-axis direction, with the sheets being substantially parallel to the XZ plane. The rotor core 9 has a through hole 9b that penetrates through the approximate center of the rotor core 9 in the Y-axis direction, and magnet insertion holes 9c that are spaced apart in the circumferential direction of the rotor core 9 and penetrate the rotor core 9 in the Y-axis direction.
[0025] As shown in Figure 2, the shaft 10 extends in the Y-axis direction and is fixed to the rotor core 9 by being inserted into the through hole 9b of the rotor core 9. The magnet 11 extends in the Y-axis direction and is inserted into the magnet insertion hole 9c of the rotor core 9. At this time, a gap G (see Figure 4) is formed between the circumferential surface of the magnet 11 and the circumferential surface of the magnet insertion hole 9c of the rotor core 9. Note that the gap G is exaggerated in Figure 4 and other figures.
[0026] The first end plate 12 is fixed to the Y-axis + side end of the rotor core 9 by means of welding or other means, as shown in Figure 2. However, the means of fixing the first end plate 12 to the Y-axis + side end of the rotor core 9 are not limited, and it may be fixed to the Y-axis + side end of the rotor core 9 by means of claws formed on the first end plate 12, for example.
[0027] The first end plate 12 is made of, for example, an electrical steel sheet and has a basically circular shape when viewed from the Z-axis direction. Figure 3 is a view from the Y-axis+ side of the rotor of this embodiment in which the magnet is covered by the cover portion of the first end plate. Figure 4 is a cross-sectional view showing the rotor of this embodiment in which the magnet is covered by the cover portion of the first end plate. Figure 5 is a diagram showing the convex portion of the first end plate.
[0028] As shown in Figures 3 and 4, the first end plate 12 includes a slit 12a, a covering portion 12b, and a protrusion 12c. As shown in Figure 3, the slit 12a is positioned to surround the magnet insertion hole 9c of the rotor core 9, except for a portion of it (for example, the radially outer end of the rotor core 9 in the magnet insertion hole 9c), and is, for example, roughly C-shaped.
[0029] As shown in Figure 3, when viewed from the Y-axis direction, the entire area of the magnet insertion hole 9c of the rotor core 9 is located within a first region AR1 enclosed by the outer peripheral edge OE1 of the slit 12a and the line L1 connecting the opening end 12d of the slit 12a. Therefore, the opening end 12d of the slit 12a is located radially outward of the rotor core 9 relative to the radially outward end of the rotor core 9 in the magnet insertion hole 9c of the rotor core 9.
[0030] Here, the C-shape is not limited to a rectangular shape, but also includes curved or polygonal shapes. In short, it is a shape that allows the entire area of the magnet insertion hole 9c of the rotor core 9 to be placed within the first region AR1 of the slit 12a when viewed from the Y-axis direction. At this time, as shown in Figure 3, it is preferable that the magnet insertion hole 9c of the rotor core 9 and the slit 12a of the first end plate 12 partially overlap when viewed from the Y-axis direction.
[0031] As shown in Figure 3, the covering portion 12b is formed in the inner region of the slit 12a. That is, the covering portion 12b forms a second region AR2 enclosed by the inner peripheral edge IE of the slit 12a and the line L1 connecting the opening end 12d of the slit 12a. The covering portion 12b is, for example, substantially rectangular when viewed from the Y-axis direction and covers at least a part of the magnet 11.
[0032] The cover portion 12b can be bent and unbent along the bending line L2 so that the entire Y-axis positive end of the magnet insertion hole 9c of the rotor core 9 can be exposed. The bending line L2 may be positioned on a line L1 connecting the opening ends 12d of the slit 12a, for example, as shown in Figure 3.
[0033] However, the bending line L2 should be positioned such that when the cover portion 12b is bent, the entire Y-axis+ end of the magnet insertion hole 9c of the rotor core 9 is exposed. Incidentally, the bending line L2 may be positioned, for example, on the Y-axis- side of the first end plate 12.
[0034] As shown in Figures 4 and 5, the protrusion 12c protrudes from the cover portion 12b toward the Y-axis. The Y-axis-side end of the protrusion 12c is in contact with the Y-axis-positive end of the magnet 11. The protrusion 12c can be formed, for example, by pressing a part of the first end plate 12 toward the Y-axis. However, the protrusion 12c may be formed from a separate component from the first end plate 12 and fixed to the Y-axis-side end of the first end plate 12.
[0035] Here, the protrusion 12c is preferably positioned to straddle the bending line L2, as shown in Figures 3 and 5. This suppresses springback when the cover portion 12b is bent back. In this case, as shown in Figure 4, if the protrusion 12c interferes with the rotor core 9, it is preferable that a recess 9d is formed in the rotor core 9 to accommodate the protrusion 12c.
[0036] The second end plate 13 is fixed to the Y-axis side end of the rotor core 9 by means of welding or other means, as shown in Figure 2, and the magnet 11 is sandwiched and fixed between the protrusion 12c of the first end plate 12 and the second end plate 13.
[0037] However, the means for fixing the second end plate 13 to the Y-axis side end of the rotor core 9 are not limited, and it may be fixed to the Y-axis side end of the rotor core 9 by, for example, claws formed on the second end plate 13.
[0038] The second end plate 13 is made of, for example, electrical steel sheet and has a basically circular shape when viewed from the Z-axis direction. Here, the second end plate 13 is preferably constructed to be substantially the same as the first end plate 12.
[0039] Figure 6 is a view from the Y-axis side of the rotor of this embodiment, showing the magnet covered by the cover portion of the second end plate. Figure 7 is a cross-sectional view showing the rotor of this embodiment, showing the magnet covered by the cover portion of the second end plate.
[0040] In short, although a detailed explanation will be omitted, the second end plate 13, as shown in Figures 6 and 7, comprises a slit 13a arranged to surround the magnet insertion hole 9c of the rotor core 9 except for a portion thereof, a covering portion 13b that forms the inner region of the slit 13a and covers at least a portion of the magnet 11, and a protrusion 13c that protrudes from the covering portion 13b toward the Y-axis + side and contacts the Y-axis - end of the magnet 11.
[0041] This allows the magnet 11 to be sandwiched and fixed between the protrusion 12c of the first end plate 12 and the protrusion 13c of the second end plate 13. In addition, the slit 12a of the first end plate 12, the gap G between the magnet insertion hole 9c of the rotor core 9 and the magnet 11, and the slit 13a of the second end plate 13 can be connected.
[0042] As shown in Figure 1, the housing 3 houses the motor 2. For example, with the shaft 10 of the rotor 6 passing through the Y-axis end of the housing 3, the inside of the housing 3 is substantially sealed. However, the housing 3 only needs to house at least the rotor 6 of the motor 2, and may also house other drive transmission mechanisms such as clutches and gears.
[0043] The cooling medium 4 is housed inside the housing 3, as shown in Figure 1. The cooling medium 4 may be a liquid such as oil used as a cooling medium. The cooling medium 4 penetrates the gap G between the magnet insertion hole 9c of the rotor core 9 and the magnet 11 through the slit 12a of the first end plate 12 or the slit 13a of the second end plate 13.
[0044] In other words, the cooling medium 4 is in direct contact with the magnet 11. This allows the magnet 11 to be efficiently cooled by the cooling medium 4. The cooling medium 4 may also be circulated inside the housing 3 by a pump, which is not shown in the diagram. Furthermore, the cooling medium 4 can be any medium that can penetrate the gap G between the magnet insertion hole 9c of the rotor core 9 and the magnet 11, for example, it may be a gas.
[0045] Next, the manufacturing method of the rotor according to this embodiment will be described. Figure 8 is a cross-sectional view showing the state in which the first end plate is fixed to the rotor core. Figure 9 is a view from the Y-axis+ side of the state in which the first end plate is fixed to the rotor core. Figure 10 is a cross-sectional view showing the state in which the cover portion of the first end plate is folded. Figure 11 is a view from the Y-axis+ side of the state in which the cover portion of the first end plate is folded. Figure 12 is a cross-sectional view showing the state in which a magnet is inserted into the magnet insertion hole of the rotor core. Figure 13 is a view from the Y-axis+ side of the state in which a magnet is inserted into the magnet insertion hole of the rotor core.
[0046] Here, the first end plate 12 is assumed to have a slit 12a, a covering portion 12b, and a protrusion 12c formed in advance, and the second end plate 13 is assumed to have a slit 13a, a covering portion 13b, and a protrusion 13c formed in advance.
[0047] First, the electromagnetic steel sheets 9a are laminated to form the rotor core 9. Then, as shown in Figure 8, the first end plate 12 is fixed to the Y-axis + side end of the rotor core 9, and the second end plate 13 is fixed to the Y-axis - side end of the rotor core 9.
[0048] As a result, as shown in Figure 9, the entire area of the magnet insertion hole 9c of the rotor core 9 is positioned within the first region AR1 when viewed from the Y-axis direction. Also, as shown in Figure 6, the entire area of the magnet insertion hole 9c of the rotor core 9 is positioned within the third region AR3, which is enclosed by the outer peripheral edge OE2 of the slit 13a of the second end plate 13 and the line L3 connecting the open end 13d of the slit 13a.
[0049] In this case, when viewed from the Y-axis direction, the magnet insertion hole 9c of the rotor core 9, the slit 12a of the first end plate 12, and the slit 13a of the second end plate 13 should partially overlap.
[0050] Next, as shown in Figure 10, the covering portion 12b and the protruding portion 12c are bent towards the Y-axis + side along the bending line L2 of the first end plate 12. As a result, as shown in Figure 11, a magnet insertion hole 12e is formed in the region enclosed by the outer peripheral edge OE1 of the slit 12a of the first end plate 12 and the bending line L2.
[0051] At this time, as shown in Figures 10 and 11, the entire area of the magnet insertion hole 9c of the rotor core 9 is positioned within the magnet insertion hole 12e of the first end plate 12 when viewed from the Y-axis direction. In other words, when the protrusion 12c is bent along the bending line L2, the protrusion 12c does not interfere with the magnet insertion hole 9c of the rotor core 9 when viewed from the Y-axis direction.
[0052] Next, as shown in Figures 12 and 13, the magnet 11 is inserted into the magnet insertion hole 9c of the rotor core 9 through the magnet insertion hole 12e of the first end plate 12. At this time, a gap G is formed between the circumferential surface of the magnet insertion hole 9c of the rotor core 9 and the circumferential surface of the magnet 11. Also, as shown in Figure 7, the Y-axis side end of the magnet 11 contacts the protrusion 13c of the second end plate 13.
[0053] Next, as shown in Figures 3 and 4, the cover portion 12b and the protrusion 12c are bent back towards the Y-axis using the bend line L2 of the first end plate 12, so that the protrusion 12c of the first end plate 12 comes into contact with the Y-axis end of the magnet 11. This allows the magnet 11 to be sandwiched and fixed between the protrusion 12c of the first end plate 12 and the protrusion 13c of the second end plate 13.
[0054] In this case, if the protrusion 12c is positioned to straddle the bending line L2, springback when the cover portion 12b is bent back can be suppressed. Therefore, the state in which the magnet 11 is fixed between the protrusion 12c of the first end plate 12 and the protrusion 13c of the second end plate 13 can be maintained well.
[0055] Subsequently, for example, the rotor 6 can be manufactured by passing the shaft 10 through the through hole 9b of the rotor core 9 and fixing it in place. In this case, when current flows between the first end plate 12 and the second end plate 13 in the rotor 6, eddy currents are generated in the Y-axis direction, causing eddy losses in the motor 2.
[0056] Therefore, for example, after manufacturing the rotor 6, a voltage is applied between the first end plate 12 and the second end plate 13, and the amount of bending back of the cover portion 12b of the first end plate 12 is adjusted so that the measured current value is less than a preset threshold. Here, Figure 14 shows the configuration of a control system for adjusting the amount of bending back of the cover portion 12b of the first end plate 12.
[0057] For example, as shown in Figure 14, a voltage is applied between the first end plate 12 and the second end plate 13 of the rotor 6 manufactured in this case using the measuring instrument 20, and the current value flowing between the first end plate 12 and the second end plate 13 is measured.
[0058] Then, the control device 21 should control the bending device 22 that bends the cover portion 12b of the first end plate 12 so that the current value flowing between the first end plate 12 and the second end plate 13 of the next manufactured rotor 6 is less than a preset threshold.
[0059] This allows the amount of contact between the protrusion 12c of the first end plate 12 and the magnet 11 to be adjusted, thereby suppressing the current flowing between the first end plate 12 and the second end plate 13 to a preset threshold or less. As a result, eddy losses in the motor 2 can be suppressed.
[0060] Here, the bending device 22 may be configured, for example, to bend the cover portion 12b of the first end plate 12 with a pin or the like. Note that the measurement parameter is not limited to the current value, but may also be the voltage value between the first end plate 12 and the second end plate 13, or the temperature around the cover portion 12b.
[0061] Incidentally, when measuring the temperature around the cover portion 12b, it can be measured non-contact. Also, the timing for measuring the measurement parameters is not limited to after the rotor 6 is completed, but can be anytime after the magnet 11 is fixed with the first end plate 12 and the second end plate 13.
[0062] In typical rotors, high-temperature resin is injected under high pressure between the magnets and the magnet insertion holes in the rotor core to fix the magnets in place. Therefore, in typical rotors, the electromagnetic steel sheets and magnets must be constructed to withstand the high temperature and pressure of the resin. Moreover, typical rotors have had quality issues such as the electromagnetic steel sheets floating when the resin is injected under high pressure.
[0063] In contrast, the manufacturing method of the rotor 6, the rotor 6, the drive device 1, and the first end plate 12 of this embodiment are configured to fix the magnet 11 using the protrusion 12c of the first end plate 12.
[0064] In other words, the magnet 11 is fixed without using resin. Therefore, the electromagnetic steel sheet 9a and the magnet 11 do not need to be constructed to withstand the high temperature and pressure of resin, and the special requirements of the electromagnetic steel sheet 9a and the magnet 11 for constructing the rotor 6 can be reduced. Moreover, quality issues such as the electromagnetic steel sheet 9a floating can be suppressed.
[0065] In this case, if the second end plate 13 also has a protrusion 13c, the magnet 11 can be firmly fixed by the protrusion 12c of the first end plate 12 and the protrusion 13c of the second end plate 13.
[0066] Furthermore, in this embodiment, the method for manufacturing the rotor 6, the rotor 6, the drive device 1, and the first end plate 12 allow the slit 12a of the first end plate 12 to be continuous with the gap G between the magnet insertion hole 9c of the rotor core 9 and the magnet 11.
[0067] Therefore, the cooling medium 4 can be introduced into the gap G between the magnet insertion hole 9c of the rotor core 9 and the magnet 11, allowing the magnet 11 to be directly cooled by the cooling medium 4. This makes it possible to cool the magnet 11 more efficiently than with a typical rotor 6. This suppresses thermal demagnetization of the magnet 11. In particular, if a slit 13a is also formed in the second end plate 13, the magnet 11 can be cooled even more efficiently.
[0068] This disclosure is not limited to the embodiments described above, and may be modified as appropriate without departing from the spirit of the invention.
[0069] For example, in the above embodiment, the protrusion 12c of the first end plate 12 is positioned to straddle the bending line L2, but as shown in Figure 15, it may be positioned so as not to straddle the bending line L2. In short, the protrusion 12c only needs to be positioned in a location that can contact the magnet 11.
[0070] Furthermore, the shape of the protrusion 12c is not limited to a roughly rectangular shape when viewed from the Y-axis direction, but may be a polygon, ellipse, or circle. Moreover, the number of protrusions 12c is not limited to one, but may be multiple. The same applies to the protrusion 13c of the second end plate 13.
[0071] For example, as shown in Figure 16, an insulating member 23 may be placed between the protrusion 12c of the first end plate 12 and the magnet 11. The same applies between the protrusion 13c of the second end plate 13 and the magnet 11. This reduces the eddy loss of the motor 2.
[0072] For example, a groove may be formed along the bending line L2. This allows the covering portion 12b of the first end plate 12 to be easily bent. The same applies to the second end plate 13.
[0073] For example, in the above embodiment, the magnet insertion hole 9c of the rotor core 9 and the slit 12a of the first end plate 12 partially overlap, but the magnet insertion hole 9c of the rotor core 9 and the slit 12a of the first end plate 12 do not overlap, and for example, the slit 12a of the first end plate 12 and the magnet insertion hole 9c of the rotor core 9 are continuous through the gap between the rotor core 9 and the first end plate 12. The same applies to the relationship between the magnet insertion hole 9c of the rotor core 9 and the slit 13a of the second end plate 13.
[0074] For example, in the above embodiment, the first end plate 12 and the second end plate 13 are fixed to the rotor core 9 before inserting the magnet 11 into the magnet insertion hole 9c of the rotor core 9. However, the first end plate 12 and the second end plate 13 may be fixed to the rotor core 9 after inserting the magnet 11 into the magnet insertion hole 9c of the rotor core 9, and the magnet 11 may be fixed by sandwiching it between the first end plate 12 and the second end plate 13.
[0075] For example, in the above embodiment, a protrusion 12c is formed in advance on the first end plate 12 and a protrusion 13c is formed in advance on the second end plate 13. However, the protrusion 12c or 13c may be formed after inserting the magnet 11 into the magnet insertion hole 9c of the rotor core 9.
[0076] For example, the second end plate 13 in the above embodiment has a configuration that is substantially the same as the first end plate 12, but the slit 13a and the protrusion 13c may be omitted. [Explanation of symbols]
[0077] 1. Drive unit 2 motors 3 Housing 4 Cooling medium 5 stator 6 rotors 7 Stator core, 7a Through hole 8 coils 9 rotor core, 9a electromagnetic steel sheet, 9b through hole, 9c magnet insertion hole, 9d recess 10 shafts 11 Magnets 12 First end plate, 12a Slit, 12b Cover portion, 12c Protrusion, 12d End of slit on the opening side, 12e Magnet insertion hole 13 Second end plate, 13a Slit, 13b Cover portion, 13c Protrusion, 13d End portion on the opening side of the slit 20 Measuring Instruments 21 Control device 22 Bending device 23 Insulating material AR1 First Domain AR2 Second Domain AR3 Third Domain G void area IE First end plate inner periphery OE1 Outer edge of the slit of the first end plate OE2 Outer edge of the slit on the second end plate L1 The line connecting the open ends of the slits in the first end plate. L2 Bending Line L3 The line connecting the open ends of the slits in the second end plate.
Claims
1. A method for manufacturing a rotor in which a rotor core made of laminated electromagnetic steel sheets is sandwiched between a first end plate and a second end plate, The first end plate, which has a C-shaped slit formed on it, is fixed to one end of the rotor core in the axial direction, and the magnet insertion hole of the rotor core and the slit of the first end plate are made continuous. The steps include fixing the second end plate to the other axial end of the rotor core, The process involves sandwiching and fixing a magnet inserted into the magnet insertion hole of the rotor core between a protrusion formed on the first end plate at a position overlapping with the magnet in the axial direction of the rotor core, and the second end plate. Equipped with, A method for manufacturing a rotor, wherein the protrusion is positioned so as to straddle a line connecting the ends on the opening side of the slit.
2. When inserting the magnet into the magnet insertion hole of the rotor core, the cover portion located inside the C-shaped slit of the first end plate is bent to form a magnet insertion hole in the first end plate, and the magnet insertion hole of the rotor core is exposed, and the magnet is inserted into the magnet insertion hole of the rotor core through the magnet insertion hole of the first end plate. The method for manufacturing a rotor according to claim 1, wherein when fixing the magnet, the covering portion of the first end plate is bent back to cover the magnet insertion hole of the rotor with the covering portion, and the protrusion formed on the covering portion of the first end plate is brought into contact with the magnet.
3. The method for manufacturing a rotor according to claim 2, wherein the covering portion of the first end plate is bent or unbent along a predetermined bending line.
4. A method for manufacturing a rotor according to claim 2 or 3, wherein the first end plate, which has the protrusion formed thereon, is fixed to one end of the rotor core in the axial direction.
5. A step of measuring the value of a preset measurement parameter when a voltage is applied between the first end plate and the second end plate after fixing the magnet, A step of adjusting the amount of bending back of the cover portion of the first end plate so that the value of the measurement parameter becomes smaller than a preset threshold, A method for manufacturing a rotor according to claim 2 or 3, comprising the following:
6. A rotor in which a rotor core made of laminated electromagnetic steel sheets is sandwiched between a first end plate and a second end plate, The first end plate is, The rotor core has a C-shaped slit that is continuous with the magnet insertion hole, A convex portion is formed in the first end plate in the axial direction of the rotor core, at a position that overlaps with the magnet inserted into the magnet insertion hole of the rotor core, and protrudes toward the magnet, Equipped with, The protrusion of the first end plate is positioned to straddle the line connecting the opening ends of the slit, The magnet is sandwiched and fixed between the protrusion of the first end plate and the second end plate. A rotor in which a gap is formed between the magnet insertion portion of the rotor core and the magnet.
7. The rotor according to claim 6, wherein the second end plate is provided with a slit continuous with the magnet insertion hole of the rotor core.
8. The second end plate is formed in a position on the second end plate that overlaps with the magnet in the axial direction of the rotor core, and has a protrusion that protrudes toward the magnet. The rotor according to claim 6 or 7, wherein the magnet is sandwiched and fixed between the protrusion of the first end plate and the protrusion of the second end plate.
9. A motor comprising the rotor described in claim 6 or 7, A housing for the motor, A cooling medium supplied to the inside of the housing, A drive device equipped with the following features.
10. An end plate used to sandwich a rotor core made of laminated electrical steel sheets, With the end plate fixed to the axial end of the rotor core, the rotor core has a C-shaped slit that is continuous with the magnet insertion hole, With the end plate fixed to the axial end of the rotor core, the end plate has a convex portion formed in the axial direction of the rotor core that overlaps with the magnet inserted into the magnet insertion hole of the rotor core, and which protrudes toward the magnet, Equipped with, The aforementioned protrusion is an end plate positioned to straddle a line connecting the opening ends of the slit.