Method for manufacturing rotor

Abstract

To provide a method for manufacturing a rotor having a rotor shaft having a metal part and a resin part which can position rotation directions of the respective components with high dimensional accuracy.SOLUTION: A method for manufacturing a rotor 10 includes: a component arrangement step of arranging a resolver rotor 60, a rotor yoke 21, and a metal part 31 of a rotor shaft 30, in a first mold 110; and a resin filling step of filling a cavity CV formed by combining the first mold 110 with a second mold 120 with a resin and forming a resin part 40 of the rotor shaft 30, and integrally insert molding the resolver rotor 60, the rotor yoke 21, and the metal part 31. The first mold 110 is provided with a plurality of positioning parts P1, P2 and P3 for positioning each of the resolver rotor 60, the rotor yoke 21, and the metal part 31 in rotation directions of the rotor 10.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a rotor. [Background technology]

[0002] In recent years, efforts to realize a low-carbon or carbon-free society have been gaining momentum, and research and development into electrification technologies has been conducted in order to reduce CO2 emissions and improve energy efficiency in vehicles. Electrification technologies include rotating electrical machines such as electric motors and generators.

[0003] For example, a rotor used in a motor is described in Patent Document 1. In the rotor of Patent Document 1, a permanent magnet, a rotor yoke, and a boss are molded with resin and fixed in place. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4552267 Summary of the Invention [Problem to be solved by the invention]

[0005] The rotor may be provided with a resolver rotor that detects the rotation parameters (e.g., rotation angle) of the rotor. When each part of the rotor, including the resolver rotor, is placed in a mold and insert-molded with resin, it is necessary to properly align the rotational position of each part with high dimensional accuracy, i.e., the phase.

[0006] The present invention provides a method for manufacturing a rotor having a rotor shaft with a metal portion and a resin portion, which method enables positioning of each component in the rotational direction with high dimensional accuracy. [Means for solving the problem]

[0007] The present invention relates to a rotor yoke formed by laminating a plurality of electromagnetic steel sheets each having a substantially annular shape; a rotor shaft having a metal portion provided on one end side, which serves as an output shaft or an input shaft, and a resin portion provided on the other end side, which is joined to an end of the metal portion, the rotor shaft being inserted through the rotor yoke and rotating integrally with the rotor yoke; a resolver rotor provided in the resin portion and capable of detecting a rotation parameter of the rotor, a component placement process of placing the resolver rotor, the rotor yoke, and the metal portion of the rotor shaft in a first mold; a resin filling step of filling a cavity formed by combining the first mold, in which the resolver rotor, the rotor yoke, and the metal part are arranged, with a second mold surrounding the metal part, to form the resin part of the rotor shaft, and insert-molding the resolver rotor, the rotor yoke, and the metal part together; The first mold is provided with a plurality of positioning portions that position the resolver rotor, the rotor yoke, and the metal portion in the rotational direction of the rotor in the component placement step. Effect of the Invention

[0008] According to the present invention, the components can be positioned in the rotational direction with high dimensional accuracy. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view of a rotor 10 according to an embodiment of the present invention. [Diagram 2] 2 is an exploded perspective view of the rotor 10 excluding the resin portion 40. FIG. [Diagram 3] 1A to 1G are diagrams illustrating a manufacturing method of a rotor 10 according to an embodiment of the present invention, in which (a) to (g) show a component placement step, and (h) shows a resin filling step. [Figure 4] 2 is a cross-sectional view of a first die 110 and a second die 120 of a die 100 used in manufacturing a rotor 10. FIG. [Diagram 5] 1 is a cross-sectional view of the die 100 showing a state in which the resolver rotor 60, the collar member 70, the rotor yoke 21, and the metal part 31 of the rotor shaft 30 are arranged in the die 100 and a cavity CV is formed. [Figure 6] 1 is a cross-sectional view of the mold 100 showing a state in which a resin portion 40 of a rotor shaft 30 has been formed by filling a cavity CV with resin. FIG. [Figure 7] 2 is a perspective view of a protrusion 112 of a first mold 110 and a metal part 31 arranged on the protrusion 112. FIG. [Figure 8] 1 is a diagram showing a rotor 10 including a rotor yoke 21L whose thickness in the lamination direction is increased by a length H1. [Figure 9] FIG. 1 shows a die 100 (left diagram) used when manufacturing a rotor 10 having a rotor yoke 21, and a die 100 (right diagram) provided with a spacer 130 and used when manufacturing a rotor 10 having a rotor yoke 21L. [Figure 10] FIG. 1 shows a mold 100 (left figure) used when manufacturing a rotor 10 having a rotor yoke 21, and a modified example of the mold 100 (right figure) provided with a spacer 130 and used when manufacturing a rotor 10 having a rotor yoke 21L. [Figure 11] 13A and 13B are diagrams showing a modified example of the positioning portion P3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotor according to an embodiment of the present invention will now be described with reference to the accompanying drawings.

[0011] [Overall rotor structure] 1 and 2, the rotor 10 rotates about a rotation axis RC and has a generally annular shape centered on the rotation axis RC. The rotor 10 is disposed on the inner periphery of a stator (not shown) and, together with the stator, is one of the components that constitute a rotating electric machine such as an electric motor or a generator.

[0012] The rotor 10 includes a rotor yoke 21 having a substantially annular shape centered on a rotation axis RC, and a rotor shaft 30 that is inserted through the rotor yoke 21 and rotates integrally with the rotor yoke 21. Hereinafter, the direction in which the rotation axis RC extends is also referred to as the axial direction, and the direction perpendicular to the axial direction is also referred to as the radial direction.

[0013] The rotor yoke 21 is formed by stacking a plurality of electromagnetic steel plates in the axial direction, each having a substantially annular shape centered on the rotation axis RC. A plurality of permanent magnets 22 are embedded in the rotor yoke 21 along the circumferential direction. The permanent magnets 22 are arranged at equal intervals along the circumferential direction of the rotor yoke 21, and in the example of FIG. 2, a total of eight permanent magnets 22 are arranged at 45 degree intervals. Hereinafter, the rotor yoke 21 in which the permanent magnets 22 are embedded will also be referred to simply as the rotor yoke 21.

[0014] The inner circumferential surface 21a of the rotor yoke 21 is provided with a plurality of engagement portions 21a1 that engage with the rotor shaft 30. Each engagement portion 21a1 is, for example, a groove extending in the axial direction. As will be described in detail later, the resin portion 40 of the rotor shaft 30 engages with the engagement portions 21a1 and is joined to the rotor yoke 21, thereby enabling the rotor yoke 21 and the rotor shaft 30 to rotate integrally. Note that each engagement portion 21a1 is not limited to a groove, and may be, for example, a protrusion that protrudes toward the inner circumferential side.

[0015] Further, the outer peripheral surface 21b of the rotor yoke 21 is provided with an engagement groove 21b1 that can be engaged with a positioning portion P2 (described later) provided in a mold 100 used in the manufacturing process of the rotor 10.

[0016] The rotor shaft 30 extends in the axial direction around the rotation axis RC. For example, when the rotating electric machine functions as an electric motor, the rotor shaft 30 serves as an output shaft, and when the rotating electric machine functions as a generator, the rotor shaft 30 serves as an input shaft. In the following, the case where the rotating electric machine functions as an electric motor may be described as an example.

[0017] The rotor shaft 30 has a metal portion 31 formed of metal and provided at one axial end, and a resin portion 40 formed of resin and provided at the other axial end. In the following, the one axial end where the metal portion 31 is provided will also be referred to as the first side, and the other axial end where the resin portion 40 is provided will also be referred to as the second side.

[0018] The metal part 31 is a solid shaft, and serves as an input part or an output part of a rotating electric machine. When viewed from the radial direction, the second side end 31b of the metal part 31 is provided on the inside of the rotor yoke 21, i.e., at a position overlapping the rotor yoke 21, and the first side end 31a is provided on the first side outside of the rotor yoke 21, i.e., at a position not overlapping the rotor yoke 21.

[0019] Metal part 31 has a coupling part 32 provided at end part 31a on the first side and to which a rotating body such as a gear is coupled, an intermediate part 33 provided on the second side of coupling part 32, and a connecting part 34 provided at end part 31b on the second side and connected to rotor yoke 21 via resin part 40. Coupling part 32, intermediate part 33, and connecting part 34 are all smaller than the inner diameter of rotor yoke 21.

[0020] The coupling part 32 is provided with two key grooves 37 extending in the axial direction, and a rotating body such as a gear engages with the key grooves 37 to be coupled to the metal part 31. A bearing (not shown) is attached to the intermediate part 33 via a first outer part 40B of the resin part 40, which will be described later. The connecting part 34 has a plurality of teeth formed on its outer circumferential surface, and the plurality of teeth engage with the resin part 40. The connecting part 34 is provided at a position overlapping the rotor yoke 21 when viewed from the radial direction.

[0021] Further, the second end 31b of the metal part 31 is provided with pin holes 35, 36, and 36 into which a first pin 113 and a second pin 114 provided in a die 100 used in the manufacturing process of the rotor 10 are inserted. The pin holes 35, 36, and 36 will be described later.

[0022] The resin part 40 is formed of, for example, a thermoplastic resin. The resin part 40 is joined to the second end part 31b of the metal part 31, and together with the metal part 31, constitutes the rotor shaft 30. Although details will be described later, the resin part 40 and the metal part 31 are integrally provided by insert molding.

[0023] The resin part 40 is configured as a hollow shaft having a hollow space 47. The resin part 40 is joined to the metal part 31 so as to cover the intermediate part 33 and the connection part 34 of the metal part 31 from the radial outside. In other words, the joint part 50 where the resin part 40 and the metal part 31 are joined is configured as a two-layer structure in which the metal part 31 is arranged on the inside in the radial direction and the resin part 40 is arranged on the outside.

[0024] Resin portion 40 is provided so as to penetrate rotor yoke 21. Specifically, resin portion 40 has an intermediate portion 40A provided at an inner position of rotor yoke 21 when viewed from the radial direction, i.e., at a position overlapping rotor yoke 21, and a first outer portion 40B and a second outer portion 40C provided at outer positions on the first and second sides of rotor yoke 21 when viewed from the radial direction, i.e., at positions not overlapping rotor yoke 21.

[0025] Intermediate portion 40A of resin portion 40 engages with a plurality of engaging portions 21a1 provided on inner circumferential surface 21a of rotor yoke 21 and is joined to rotor yoke 21. As a result, rotor yoke 21 and resin portion 40 rotate integrally about rotation axis RC.

[0026] A part of the joint 50 between the resin part 40 and the metal part 31 is provided in the middle part 40A of the resin part 40, that is, in a position overlapping with the rotor yoke 21 when viewed from the radial direction. As a result, when the rotor yoke 21 rotates around the rotation axis RC, for example, and the rotational torque from the rotor yoke 21 is transmitted to the metal part 31 via the resin part 40, the rotational torque is transmitted to the metal part 31 with almost no torsional moment being generated in the resin part 40. Therefore, the transmission of the rotational torque to the metal part 31 is excellent.

[0027] The portion of the joint 50 provided at the position of the intermediate portion 40A is preferably provided at a position overlapping the first end portion 21c of the rotor yoke 21 when viewed from the radial direction. This allows the metal portion 31 to be configured to be short and light in weight.

[0028] The second outer portion 40C of the resin portion 40 is provided with a resolver holding portion 43 that holds the resolver rotor 60.

[0029] The resolver rotor 60 held by the resolver holding portion 43, together with a resolver stator (not shown), constitutes a resolver capable of detecting rotation parameters (e.g., a rotation angle) of the rotor shaft 30. The resolver rotor 60 is joined to the resolver holding portion 43 so as to be rotatable integrally therewith.

[0030] The resolver rotor 60 is formed by laminating silicon steel plates having a substantially annular shape. On the outer peripheral surface of the resolver rotor 60, a plurality of protruding parts 62 are formed, which are evenly arranged in the circumferential direction and protrude outward in an arc shape in the radial direction. In this embodiment, four protruding parts 62 are formed and arranged at 90 degree intervals in the circumferential direction. Each protruding part 62 is provided with a phase determination hole 61, which is used to determine the rotational position of the resolver rotor 60, the rotor yoke 21, and the metal part 31 (i.e., to match the phase) when the resolver rotor 60 is arranged in a die 100 described later.

[0031] The first outer portion 40B of the resin portion 40 is provided with a positioning portion 44 that abuts against the rotor yoke 21 in the axial direction to regulate the axial position of the rotor yoke 21, and the second outer portion 40C is provided with a positioning portion 46 that abuts against the resolver rotor 60 outside the resolver holding portion 43 to regulate the axial position of the resolver rotor 60. The positioning portions 44, 46 are formed integrally with the resin portion 40. A collar member 70 is provided between the resolver rotor 60 and the rotor yoke 21. In this manner, the positioning portions 44, 46 and the collar member 70 determine the relative axial positions of the resolver rotor 60, the rotor yoke 21, and the rotor shaft 30.

[0032] The resin part 40 is provided on the first outer part 40B and the second outer part 40C, respectively, and has a first side bearing holding part 41 and a second side bearing holding part 42 that hold a bearing (not shown).

[0033] The first-side bearing retaining portion 41 and the second-side bearing retaining portion 42 have substantially the same outer diameter. Although not shown in the figure, the first-side bearing retaining portion 41 and the second-side bearing retaining portion 42 are rotatably supported via bearings on, for example, a case that houses a rotating electric machine.

[0034] As described above, the rotor 10 has the rotor shaft 30 made of metal and resin. Therefore, the weight of the rotor 10 can be reduced compared to a rotor shaft made entirely of metal.

[0035] Furthermore, if the entire rotor shaft were made of metal, it would be necessary to process the surface of the rotor shaft (for example, polishing the portion that is press-fitted into rotor yoke 21), which would increase the manufacturing cost of the rotor shaft. On the other hand, in this embodiment, the portion of rotor shaft 30 that is joined to rotor yoke 21 is resin part 40, so the cost of processing rotor shaft 30 can be reduced.

[0036] Furthermore, the moment of inertia about the rotation axis RC of the rotor 10 depends greatly on the outer diameter and the inner diameter of the rotor yoke 21. Therefore, even if the rotor shaft 30 arranged along the rotation axis RC is configured to include the resin part 40 as in this embodiment, it is possible to prevent the moment of inertia of the rotor 10 from changing significantly (i.e., becoming smaller) and to achieve weight reduction, compared to when the entire rotor shaft is made of metal.

[0037] [Rotor manufacturing method] Next, a manufacturing method of the rotor 10 will be described with reference to FIGS.

[0038] The manufacturing method of the rotor 10 includes a component arrangement process of arranging components of the rotor 10 in a mold 100, as shown in (a) to (g) of Fig. 3, and a resin filling process of filling a cavity CV formed in the mold 100 with molten resin (hereinafter also simply referred to as resin), as shown in (h) of Fig. 3. In this embodiment, the mold 100 includes a first mold 110 provided on the lower side and a second mold 120 provided on the upper side.

[0039] Specifically, in a component placement step, the resolver rotor 60, the collar member 70, the rotor yoke 21 in which the permanent magnets 22 are embedded, and the metal part 31 of the rotor shaft 30 are placed in the first mold 110 ((a) to (e) of FIG. 3). Next, the second mold 120 is placed over the first mold 110 from above, and the mold is clamped ((f) to (g) of FIG. 3). At this time, a cavity CV into which resin can be filled is formed inside the first mold 110 and the second mold 120. Then, in a resin filling step, the cavity CV is filled with resin to form the resin part 40 of the rotor shaft 30, and the resolver rotor 60, the collar member 70, the rotor yoke 21, and the metal part 31 are integrally insert-molded ((h) of FIG. 3). In this manner, the rotor 10 is manufactured.

[0040] The manufacturing method of the rotor 10 will be described below in detail while explaining the details of the die 100.

[0041] 4 to 6, the first mold 110 has a first space 111 in which the resolver rotor 60, the collar member 70, and the rotor yoke 21 are disposed, and a protruding portion 112 protruding upward from the bottom of the first space 111. The protruding portion 112 has a substantially cylindrical shape, and the central axis of the protruding portion 112 coincides with the central axis of the first space 111. Hereinafter, the central axis of the protruding portion 112 and the first space 111 is indicated by the symbol L1, and the direction in which the central axis extends is also referred to as the axial direction. The central axis L1 corresponds to the rotation axis RC of the rotor 10 described above.

[0042] In the first space 111, the resolver rotor 60, the collar member 70, and the rotor yoke 21 in which the permanent magnets 22 are embedded are arranged in this order from the bottom. Specifically, the resolver rotor 60, the collar member 70, and the rotor yoke 21 are arranged such that their central axes coincide with the central axis L1 of the protrusion 112 and the first space 111. In addition, the rotor yoke 21 is arranged such that the surface on the first side coincides with the parting line PL of the first mold 110 and the second mold 120.

[0043] When viewed from the radial direction, the protrusion 112 protrudes from the bottom of the first space 111 to a position overlapping with the first side end 21c of the rotor yoke 21. The metal part 31 of the rotor shaft 30 is disposed on the upper surface of the protrusion 112. Specifically, a first pin 113 protruding upward along the central axis L1 is provided on the upper surface of the protrusion 112, and the metal part 31 is disposed on the upper surface of the protrusion 112 by inserting the pin hole 35 of the metal part 31 into the first pin 113.

[0044] The first mold 110 is provided with positioning portions P1, P2, and P3 for respectively positioning the resolver rotor 60, the rotor yoke 21, and the metal portion 31. In the component arrangement process described above, since the positioning portions P1, P2, and P3 are provided in the first mold 110, the resolver rotor 60, the rotor yoke 21, and the metal portion 31 are positioned relative to each other in the rotational direction, that is, phase alignment is performed.

[0045] The positioning portions P1, P2, and P3 will be described in detail. The positioning portion P1 is provided at a position in the first space 111 where the resolver rotor 60 is disposed. Specifically, the positioning portions P1 are provided in a plurality of positions along the circumferential direction of the resolver rotor 60 and are pins that protrude upward. As described above, the resolver rotor 60 is provided with a plurality of phasing holes 61 (see FIG. 2), and the resolver rotor 60 is positioned in the rotational direction by inserting pins, which are the positioning portions P1, into the corresponding phasing holes 61.

[0046] The positioning portion P2 is provided at a position in the first space 111 where the rotor yoke 21 is disposed. Specifically, the positioning portion P2 is a plurality of protrusions provided on the inner peripheral surface of the first space 111, and extends along the axial direction. As described above, a plurality of engagement grooves 21b1 are provided on the outer peripheral surface 21b of the rotor yoke 21, and the rotor yoke 21 is positioned in the rotational direction by engaging the protrusions, which are the positioning portion P2, with the engagement grooves 21b1. This causes the phases of the resolver rotor 60 and the rotor yoke 21 to match.

[0047] The positioning portion P3 is provided on the upper surface of the protrusion 112. Specifically, the positioning portion P3 has the above-mentioned first pin 113 and a second pin 114 provided radially shifted from the first pin 113. The second pin 114 is configured to be shorter than the first pin 113.

[0048] As shown in Figure 7, a pin hole 35 is provided at the end 31b of the metal part 31 along the central axis of the metal part 31, and by inserting the first pin 113 into the pin hole 35, the central axis of the metal part 31 can be aligned with the central axis L1 of the convex part 112.

[0049] Furthermore, two pin holes 36, 36 are provided at the end 31b of the metal part 31 at a position spaced the same distance from the pin hole 35, and the two pin holes 36, 36 are provided at positions that are 180 degrees out of phase with each other relative to the pin hole 35. In other words, the three pin holes 35, 36, 36 are provided in a line. The metal part 31 is positioned in the rotational direction by inserting the second pin 114 into one of the pin holes 36, 36 with the first pin 113 inserted into the pin hole 35. This causes the phases of the resolver rotor 60, the rotor yoke 21, and the metal part 31 to match.

[0050] By providing two pin holes 36, 36 as in this embodiment, the weight balance of the metal part 31 can be made equal with respect to the central axis L1. Also, since the second pin 114 only needs to be inserted into one of the pin holes 36, 36, the positioning of the metal part 31 in the rotational direction can be made easier. However, the number of pin holes 36 is not limited to two, and may be, for example, one, or four pin holes 36 may be provided at positions that are shifted in phase from each other by 90 degrees with respect to the pin hole 35.

[0051] In this way, in the component placement process, the resolver rotor 60, the rotor yoke 21, and the metal part 31 can be positioned relative to one another in the rotational direction and aligned in phase with one another in the rotational direction. This allows the rotation parameters of the manufactured rotor 10 to be properly detected by the resolver, and the rotating electric machine can be properly controlled.

[0052] Furthermore, since the positioning portions P1, P2, and P3 are provided in the first mold 110, the arrangement and positioning of the resolver rotor 60, the rotor yoke 21, and the metal portion 31 in the component arrangement process is concentrated in the first mold 110, and the positioning of the rotational direction of each component (i.e., phase alignment) can be performed with high dimensional accuracy.

[0053] 4 and 5, the second mold 120 has a second space 121 surrounding the metal part 31 arranged on the protruding part 112 of the first mold 110. The inner surface of the second space 121 abuts against the connecting part 32 of the metal part 31, and is provided with a gap between it and the intermediate part 33 and the connecting part 34 of the metal part 31.

[0054] When the resolver rotor 60, collar member 70, rotor yoke 21, and metal part 31 are arranged in the first mold 110 and the second mold 120 is placed over the first mold 110 from above, a cavity CV corresponding to the aforementioned resin part 40 is formed in the first space 111 and the second space 121.

[0055] In the resin filling step, when resin is filled into cavity CV from a resin supply port (not shown), a resin part 40 is formed, as shown in Fig. 6. In a portion of cavity CV corresponding to first mold 110, an intermediate part 40A and a second outer part 40C of resin part 40 are formed, and in a portion of cavity CV corresponding to second mold 120, a first outer part 40B of resin part 40 is formed.

[0056] In this manner, the resolver rotor 60, the collar member 70, the rotor yoke 21, and the rotor shaft 30 are integrally insert molded to manufacture the rotor 10.

[0057] As described above, in the rotor 10 of this embodiment, the rotor shaft 30 is configured such that a metal part 31 is provided on one end side (first side) and a resin part 40 is provided on the other end side (second side), so that the axial length of the rotor shaft 30 can be adjusted by the resin part 40 according to the thickness (also referred to as the stacking thickness) of the rotor yoke 21 in the stacking direction of the electromagnetic steel sheets.

[0058] 8, when rotor 10 includes rotor yoke 21L whose lamination thickness is increased by length H1 compared to rotor yoke 21, rotor shaft 30 can be formed according to the lamination thickness of rotor yoke 21L by increasing the length of intermediate portion 40A of resin portion 40 by length H1. In this case, metal portion 31 does not need to be changed according to the lamination thickness of rotor yoke 21L, which contributes to reducing the weight of rotor shaft 30.

[0059] 9, when manufacturing a rotor 10 including a rotor yoke 21L, the rotor 10 can be manufactured by disposing a spacer 130 between the first mold 110 and the second mold 120, the spacer 130 having a length (i.e., length H1) that corresponds to the length of the rotor yoke 21L beyond the parting line PL between the first mold 110 and the second mold 120. Here, the process of disposing the spacer 130 between the first mold 110 and the second mold 120 is also referred to as a spacer disposing process.

[0060] The spacer 130 is disposed not only between the first mold 110 and the second mold 120, but also in the convex portion 112 of the first mold 110. To explain the spacer 130 attached to the convex portion 112 in detail, when a part of the convex portion 112, for example, the upper end portion 112a of the convex portion 112, is configured to be detachable from the lower end portion 112b, the spacer 130 can be provided between the upper end portion 112a and the lower end portion 112b. This allows the length of the convex portion 112 to be variably adjusted.

[0061] Furthermore, the adjustment of the length of the protrusion 112 is not limited to the configuration in which the spacer 130 is provided on the protrusion 112. For example, as in a modified example shown in Fig. 10, the protrusion 112 may be configured to be replaceable with the first mold 110, and a protrusion 112L that is longer by length H1 may be prepared separately and attached to the first mold 110. Here, the process of adjusting the length of the protrusion 112 is also referred to as a protrusion length adjustment process.

[0062] In this way, when different rotor shafts 30 are produced according to the stack thickness of rotor yokes 21, 21L, there is no need to produce different metal portions 31, and the length of rotor shaft 30 can be adjusted with resin portion 40. At this time, the length of rotor shaft 30 can be adjusted by attaching spacer 130 to mold 100, so that it is possible to easily accommodate changes in the stack thickness of rotor yoke 21 and reduce the cost of producing different rotor shafts 30.

[0063] Although one embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such an embodiment. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the claims, and it is understood that these also naturally belong to the technical scope of the present invention. In addition, the components in the above embodiment may be arbitrarily combined within the scope of the invention.

[0064] For example, in the above-described embodiment, the positioning portion P3 for positioning the metal portion 31 is provided on the upper surface of the protruding portion 112 of the first mold 110, and has a first pin 113 and a second pin 114 to be inserted into pin holes 35, 36 provided in the metal portion 31, but is not limited thereto. For example, as shown in FIG. 11, the positioning portion P3 may have a first pin hole 115 provided along the rotation axis RC (central axis L1) of the rotor 10, and a second pin hole 116 provided shifted from the first pin hole 115 in the radial direction of the rotor 10, instead of the first pin 113 and the second pin 114. In the example shown in FIG. 11, two second pin holes 116 are provided, and are provided at positions shifted from each other by 180 degrees with respect to the first pin hole 115.

[0065] For example, when the pin holes 35, 36 of the metal part 31 are changed to the first pin 38 and the second pin 39, respectively, the first pin 38 and the second pin 39 of the metal part 31 can be inserted into the first pin hole 115 and the second pin hole 116 of the first mold 110, respectively, to position the metal part 31 in the rotation direction of the rotor 10 in the first mold 110. Furthermore, although not shown in the drawings, for example, when the pin holes 35, 36 are provided in the metal part 31 as in the above-mentioned embodiment, it is also possible to position the metal part 31 in the first mold 110 in the rotation direction of the rotor 10 by engaging the pin holes 35, 36 of the metal part 31 with the first pin hole 115 and the second pin hole 116 of the first mold 110 with a knock pin or the like.

[0066] This specification describes at least the following items. In parentheses, components corresponding to the above-described embodiment are shown as examples, but the present invention is not limited to these.

[0067] (1) a rotor yoke (rotor yoke 21, 21L) formed by laminating a plurality of electromagnetic steel sheets having a substantially annular shape; a rotor shaft (rotor shaft 30) that is inserted through the rotor yoke and rotates integrally with the rotor yoke, the rotor shaft having a metal portion (metal portion 31) at one end (first side) and serving as an output shaft or an input shaft, and a resin portion (resin portion 40) at the other end (second side) and joined to an end portion (end portion 31b) of the metal portion; A method for manufacturing a rotor including a resolver rotor (resolver rotor 60) provided in the resin part and capable of detecting a rotation parameter of a rotor (rotor 10), a component placement process of placing the resolver rotor, the rotor yoke, and the metal portion of the rotor shaft in a first mold (first mold 110); a resin filling step of filling a cavity (cavity CV) formed by combining the first mold in which the resolver rotor, the rotor yoke, and the metal part are arranged with a second mold surrounding the metal part with resin to form the resin part of the rotor shaft, and insert-molding the resolver rotor, the rotor yoke, and the metal part together; The first mold is provided with a plurality of positioning portions (positioning portions P1, P2, P3) that position the resolver rotor, the rotor yoke, and the metal portion in the rotation direction of the rotor in the component placement process. A method for manufacturing a rotor.

[0068] According to (1), since the positioning portion for positioning the resolver rotor, the rotor yoke, and the metal portion in the rotational direction is provided in the first mold, the arrangement and positioning of the resolver rotor, the rotor yoke, and the metal portion are concentrated in the first mold, and therefore the positioning of each part in the rotational direction can be performed with high dimensional accuracy.

[0069] (2) A method for manufacturing a rotor according to (1), comprising the steps of: The first mold is provided with a protrusion (protrusion 112, 112L) that protrudes toward the second mold and has an upper surface on which the metal part is disposed, the upper surface of the protrusion is provided at a position overlapping the rotor yoke when viewed from a radial direction of the rotor. A method for manufacturing a rotor.

[0070] According to (2), a rotor can be manufactured in which the metal part of the rotor shaft is positioned so as to overlap the rotor yoke when viewed from the radial direction of the rotor, thereby enabling efficient transmission of rotational torque from the rotor yoke to the metal part, or from the metal part to the rotor yoke.

[0071] (3) A method for manufacturing a rotor according to (2), comprising the steps of: The positioning portion (positioning portion P3) for positioning the metal portion is provided on the upper surface of the convex portion, and has a first pin (first pin 113) and a second pin (second pin 114) to be inserted into holes (pin holes 35, 36) provided in the metal portion, The first pin is provided along a rotation axis (rotation axis RC) of the rotor, The second pin is provided so as to be shifted from the first pin in the radial direction of the rotor. A method for manufacturing a rotor.

[0072] According to (3), the first pin and the second pin provided on the convex portion of the first mold are inserted into holes provided in the metal portion, whereby the metal portion can be positioned in the rotational direction.

[0073] (4) A method for manufacturing a rotor according to (2), comprising the steps of: The positioning portion (positioning portion P3) for positioning the metal portion has a first pin hole (first pin hole 115) and a second pin hole (second pin hole 116) provided on the upper surface of the convex portion, A first pin (first pin 38) and a second pin (second pin 39) provided in the metal part are inserted into the first pin hole and the second pin hole, or the first pin hole and the second pin hole engage with holes (pin holes 35, 36) provided in the metal part via the pins, The first pin hole is provided along a rotation axis of the rotor, The second pin hole is provided so as to be shifted from the first pin hole in the radial direction of the rotor. A method for manufacturing a rotor.

[0074] According to (4), the metal part can be positioned in the rotational direction by inserting the first pin and the second pin provided on the metal part into the first pin hole and the second pin hole provided on the convex portion of the first mold.

[0075] (5) A method for manufacturing a rotor according to any one of (2) to (4), comprising the steps of: When the rotor yoke disposed in the first mold exceeds the parting line (parting line PL) between the first mold and the second mold, a spacer arrangement step of arranging a spacer (spacer 130) having a length that exceeds the parting line between the first mold and the second mold; A convex portion length adjustment process is further provided, in which the convex portion is lengthened by providing the spacer on the convex portion or by replacing the convex portion with a convex portion (convex portion 112L) that is longer than the convex portion by the length beyond the parting line. A method for manufacturing a rotor.

[0076] According to (5), even if the thickness of the rotor yoke in the lamination direction of the electromagnetic steel sheets is increased, by providing a spacer between the first and second dies and lengthening the protrusion, the resin portion formed in the resin filling step can conform to the thickness of the rotor yoke. This makes it easy to produce different rotor shafts. [Explanation of symbols]

[0077] 10 Rotor 21, 21L rotor yoke 30 rotor shaft 31 Metal Part 31b End 35, 36 pin holes 40 Resin part 60 Resolver rotor 110 First Mold 112, 112L convex part 113 1st pin 114 2nd pin 130 Spacer CV Cavity P1, P2, P3 positioning parts PL parting line RC rotation axis

Claims

1. a rotor yoke formed by laminating a plurality of electromagnetic steel sheets each having a substantially annular shape; a rotor shaft having a metal portion provided on one end side, which serves as an output shaft or an input shaft, and a resin portion provided on the other end side, which is joined to an end of the metal portion, the rotor shaft being inserted through the rotor yoke and rotating integrally with the rotor yoke; a resolver rotor provided in the resin portion and capable of detecting a rotation parameter of the rotor, a component placement process of placing the resolver rotor, the rotor yoke, and the metal portion of the rotor shaft in a first mold; a resin filling step of filling a cavity formed by combining the first mold, in which the resolver rotor, the rotor yoke, and the metal part are arranged, with a second mold surrounding the metal part, to form the resin part of the rotor shaft, and insert-molding the resolver rotor, the rotor yoke, and the metal part together, the first mold is provided with a plurality of positioning portions that position the resolver rotor, the rotor yoke, and the metal portion in a rotational direction of the rotor in the component placement process; A method for manufacturing a rotor.

2. A method for manufacturing a rotor according to claim 1, comprising the steps of: the first mold has a protrusion that protrudes toward the second mold and has an upper surface on which the metal portion is disposed; the upper surface of the protrusion is provided at a position overlapping the rotor yoke when viewed from a radial direction of the rotor. A method for manufacturing a rotor.

3. A method for manufacturing a rotor according to claim 2, comprising the steps of: the positioning portion for positioning the metal portion is provided on the upper surface of the protrusion, and has a first pin and a second pin to be inserted into holes provided in the metal portion, The first pin is provided along a rotation axis of the rotor, The second pin is provided so as to be shifted from the first pin in a radial direction of the rotor. A method for manufacturing a rotor.

4. A method for manufacturing a rotor according to claim 2, comprising the steps of: the positioning portion for positioning the metal portion has a first pin hole and a second pin hole provided in the upper surface of the protrusion, a first pin and a second pin provided in the metal part are inserted into the first pin hole and the second pin hole, or the first pin hole and the second pin hole are engaged with holes provided in the metal part via the first pin and the second pin hole; The first pin hole is provided along a rotation axis of the rotor, The second pin hole is provided so as to be shifted from the first pin hole in the radial direction of the rotor. A method for manufacturing a rotor.

5. A method for manufacturing a rotor according to any one of claims 2 to 4, comprising the steps of: When the rotor yoke disposed in the first mold exceeds a parting line between the first mold and the second mold, a spacer arrangement step of arranging a spacer between the first mold and the second mold, the spacer having a length that exceeds the parting line; and a convex portion length adjusting step of lengthening the convex portion by providing the spacer on the convex portion or by replacing the convex portion with a spacer that is longer than the convex portion by the length that exceeds the parting line. A method for manufacturing a rotor.

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