JP2024007081A - Rotor manufacturing device for rotary electric machine, and rotor manufacturing method for the rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent unwanted deformation to a radial outer side of a workpiece caused by an injection pressure at the time of an injection molding.

SOLUTION: A present invention provides a rotor manufacturing device for a rotary electric machine, that comprises: a metal molding device that can set a workpiece of a rotor core for the rotary electric machine having a magnetic hole; a movable contact part that is arranged to the metal molding, and can be moved between a contact position contacted to a front surface on a radial outer side of the workpiece and a non-contact position separated from the front surface of the radial outer side of the workpiece; an injection device that can fill a material for an injection molding into the magnetic hole in the workpiece. The movable contact part can be moved along a radial direction of the workpiece set to the metal molding device.

SELECTED DRAWING: Figure 12

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present disclosure relates to a rotor manufacturing apparatus for a rotating electrical machine and a rotor manufacturing method for a rotating electrical machine.

Regarding the manufacturing method in which a permanent magnet is inserted into a hole in a laminated iron core for a magnet-embedded rotor, and a resin material is filled between the hole and the permanent magnet, the sliding member is A technique is known in which the mold is clamped while the core is in contact with the outer periphery of the laminated core.

Japanese Patent Application Publication No. 2007-318942

However, in the above-mentioned conventional technology, when injection molding of resin material, the slide member is fixed in contact with the laminated core, so when the injection pressure increases, the radial direction of the laminated core due to the injection pressure increases. It may not be possible to prevent outward deformation. Such a problem similarly occurs in rotor cores (workpieces) for rotating electric machines having forms other than laminated cores.

Therefore, in one aspect, the present disclosure aims to prevent undesirable radially outward deformation of a workpiece due to injection pressure during injection molding.

In one aspect, a mold device capable of setting a workpiece of a rotor core for a rotating electric machine having a magnet hole;
a movable contact portion disposed in the mold device and movable between a contact position in which it contacts a radially outer surface of the workpiece and a non-contact position away from the radially outer surface of the workpiece; and,
an injection device capable of filling the magnet hole in the workpiece with an injection molding material; the movable contact portion is movable along a radial direction of the workpiece set in the mold device; A rotor manufacturing apparatus for a rotating electric machine is provided.

In one aspect, according to the present disclosure, it is possible to prevent undesirable radially outward deformation of a workpiece due to injection pressure during injection molding.

1 is a cross-sectional view schematically showing a cross-sectional structure of a motor according to an embodiment. FIG. 3 is a cross-sectional view of the rotor (a cross-sectional view taken along a plane perpendicular to the axial direction). 3 is an enlarged view of a portion related to one magnetic pole shown in FIG. 2. FIG. FIG. 7 is an enlarged view of a portion related to one magnetic pole according to a modification. 1 is a flowchart schematically showing the flow of a method for manufacturing a rotor according to the present embodiment. FIG. 3 is a plan view showing an initial workpiece prepared in a preparation process. 7 is an enlarged view of part Q1 in FIG. 6. FIG. It is a schematic diagram showing the state of the non-magnetic material inserted in the insertion process. It is a figure which shows roughly the state of the bonded magnet material filled in the filling process. It is a flowchart which shows roughly the flow of an example of a filling process. FIG. 2 is a cross-sectional view schematically showing a state in which a workpiece is set in a lower die of a manufacturing device. It is a figure which shows typically the mold clamping state in cross-sectional view. It is a figure which shows typically the state after a moving process in cross-sectional view. It is a figure which shows roughly the contact state of the movable contact part in a part range of the circumferential direction. FIG. 7 is an explanatory diagram of a movable contact mechanism according to another example. FIG. 3 is a cross-sectional view schematically showing a state during an injection molding process. FIG. 2 is a diagram schematically showing the state of force (reaction force, etc.) generated by a non-magnetic material during an injection molding process when viewed in the axial direction. It is an explanatory view of the bridge protection function by a movable contact part. It is an explanatory view of the protection function of other parts by a movable contact part by a modification.

Hereinafter, each embodiment will be described in detail with reference to the accompanying drawings. Note that the dimensional ratios in the drawings are just examples and are not limited thereto, and shapes and the like in the drawings may be partially exaggerated for convenience of explanation.

FIG. 1 is a cross-sectional view schematically showing the cross-sectional structure of a motor 1 according to an embodiment. FIG. 2 is a cross-sectional view of the rotor 30 (a cross-sectional view taken along a plane perpendicular to the axial direction). Note that in FIG. 2 and the like, for ease of viewing, only some of the parts having the same attribute may be labeled with reference numerals.

FIG. 1 shows a rotating shaft 12 of the motor 1. As shown in FIG. In the following description, the axial direction refers to the direction in which the rotating shaft (center shaft) 12 of the motor 1 extends, and the radial direction refers to the radial direction around the rotating shaft 12. Therefore, the radially outer side refers to the side away from the rotating shaft 12, and the radially inner side refers to the side facing the rotating shaft 12. Further, the circumferential direction corresponds to the direction of rotation around the rotating shaft 12.

The motor 1 may be a vehicle drive motor used, for example, in a hybrid vehicle or an electric vehicle. However, the motor 1 may be used for any other purpose.

The motor 1 is of an inner rotor type, and the stator 21 is provided so as to surround the rotor 30 on the outside in the radial direction. The stator 21 is fixed to the motor housing 10 on the outside in the radial direction. The stator 21 includes a stator core 211 made of, for example, an annular magnetic laminated steel plate, and a plurality of slots (not shown) around which the coils 22 are wound are formed inside the stator core 211 in the radial direction.

The rotor 30 is arranged radially inside the stator 21.

The rotor 30 includes a rotor core 32, a rotor shaft 34, end plates 35A and 35B, and bonded magnets 61 and 62.

The rotor core 32 is fixed to the radially outer surface of the rotor shaft 34 and rotates together with the rotor shaft 34. The rotor core 32 has a shaft hole 320 (see FIG. 2), into which the rotor shaft 34 is fitted. The rotor shaft 34 is rotatably supported by the motor housing 10 via bearings 14a, 14b. Note that the rotor shaft 34 defines the rotation axis 12 of the motor 1.

The rotor core 32 is formed of, for example, an annular magnetic laminated steel plate. In addition, in a modified example, the rotor core 32 may be formed of a green compact obtained by compressing and solidifying magnetic powder. Bonded magnets 61 and 62 (see FIG. 2) are arranged inside the rotor core 32. That is, the rotor core 32 has magnet holes 321 and 322 (see FIG. 2) that penetrate in the axial direction, and bonded magnets 61 and 62 are formed in the magnet holes 321 and 322. Each of the plurality of bonded magnets 61 and 62 is formed by injection molding a bonded magnet material (hereinafter also simply referred to as "bonded magnet material") that is a mixture of magnet powder and a binder. The injection molding method is arbitrary and may include, for example, transfer molding, resin injection by compression molding using a cylinder, and the like. Details of the method for forming the bonded magnet will be explained in connection with the manufacturing method described later.

As shown in FIG. 2, the rotor core 32 has a configuration that is rotationally symmetrical about the rotating shaft 12 when viewed in the axial direction. In the example shown in FIG. 2, the rotor core 32 is configured such that each set of bonded magnets 61 and 62 overlaps every time the rotor core 32 rotates 45 degrees about the rotation axis 12.

In the example shown in FIG. 2, the plurality of bonded magnets 61 and 62 have two types of bonded magnets 61 and 62 each forming a pair in a substantially V-shape (approximately V-shaped with the radially outer side open). It is arranged in the form of a letter. In this case, a common magnetic pole is formed between the pair of bonded magnets 61 and between the pair of bonded magnets 62. Note that the plurality of bonded magnets 61 and 62 are arranged in such a manner that south poles and north poles appear alternately in the circumferential direction. In this example, the number of magnetic poles is eight, but the number of magnetic poles is arbitrary.

Although the motor 1 having a specific structure is shown in FIG. 1, the structure of the motor 1 is not limited to this specific structure. For example, in FIG. 1, rotor shaft 34 is hollow, but may be solid.

Next, the rotor core 32 and bonded magnets 61 and 62 will be further explained with reference to FIG. 3 and subsequent figures. Although a configuration related to one magnetic pole will be described below, the same may be applied to configurations related to other magnetic poles.

FIG. 3 is an enlarged view of a portion related to one magnetic pole shown in FIG. The configuration related to one magnetic pole is basically symmetrical with respect to the d-axis. Below, the circumferential outside refers to the side away from the d-axis. Note that the d-axis is the direction of the magnetic field generated by the permanent magnets (that is, the bonded magnets 61 and 62) arranged in the rotor 30.

The rotor core 32 has a radially outer magnet hole 321 (hereinafter also referred to as "first magnet hole 321") and a radially inner magnet hole 322 (hereinafter also referred to as "second magnet hole 322"). It is formed.

Two of the first magnet holes 321 are formed in a substantially V-shape (a substantially V-shape in which the outside in the radial direction is open). However, in a modified example, two first magnet holes 321 may be formed in a straight line as a pair, or only one may be formed in a straight line (a straight line perpendicular to the d-axis). . A bonded magnet 61 is provided in each of the first magnet holes 321 . Note that gaps (cavities) are formed in the first magnet hole 321 at both ends of the bonded magnet 61 in the longitudinal direction. This gap functions as a flux barrier section. In this embodiment, a non-magnetic material 71 is arranged in the gap related to the flux barrier section. The nonmagnetic material 71 is provided adjacent to the bonded magnet 61 . For example, of the non-magnetic bodies 71 on both sides of the bonded magnet 61, the radially outer non-magnetic body 71 comes into contact with the radially outer end face of the bonded magnet 61 (in this case, surface contact). The non-magnetic material 71 may be provided in such a manner that it fills the entire flux barrier section, or may be provided in such a manner that a cavity remains in a part of the flux barrier section. Further details of the non-magnetic material 71 will be explained in connection with the manufacturing method described below.

The second magnet hole 322 is provided inside the first magnet hole 321 in the radial direction. Two of the second magnet holes 322 are formed in a substantially V-shape (a substantially V-shape in which the outside in the radial direction is open). Note that the pair of second magnet holes 322 has a wider circumferential extension range than the pair of first magnet holes 321. A bonded magnet 62 is provided in each of the second magnet holes 322 . Note that gaps (cavities) are formed in the second magnet hole 322 at both ends of the bonded magnet 62 in the longitudinal direction. This gap functions as a flux barrier section. In this embodiment, a non-magnetic material 72 is arranged in the gap related to the flux barrier section. The nonmagnetic material 72 is provided adjacent to the bonded magnet 62 . The configuration itself of the non-magnetic material 72 may be the same as that of the non-magnetic material 71 described above.

By having such a first magnet hole 321 and a second magnet hole 322, the rotor core 32 has three parts 3211, 3212, and 3213 (hereinafter referred to as the first part 3211) that are connected only through the bridge part in the radial direction. , a second portion 3212, and a third portion 3213).

Specifically, the first portion 3211 extends radially outward from the first magnet hole 321. The first portion 3211 forms a part of the outer peripheral surface 328 of the rotor core 32 .

The second portion 3212 passes between the second magnet hole 322 and the first magnet hole 321 and extends to the outer peripheral surface 328 of the rotor core 32 on both sides in the circumferential direction. The second portion 3212 forms a part of the outer circumferential surface 328 of the rotor core 32 on both sides of the first portion 3211 in the circumferential direction. The second portion 3212 forms a magnetic path for the q-axis magnetic flux. Specifically, the q-axis magnetic flux flows between the second magnet hole 322 and the first magnet hole 321 from one end of the second portion 3212 to the other end.

The third portion 3213 passes radially inside the second magnet hole 322 and extends to the outer circumferential surface 328 of the rotor core 32 on both sides in the circumferential direction. The third portion 3213 forms a part of the outer circumferential surface 328 of the rotor core 32 on both sides of the second portion 3212 in the circumferential direction.

Moreover, the rotor core 32 has such three parts 3211, 3212, and 3213, and thus has a plurality of bridge parts 41, 42, 43, and 44 that connect the three parts 3211, 3212, and 3213.

The bridge portion 41 (hereinafter also referred to as “first bridge portion 41”) supports the first portion 3211 with respect to the second portion 3212 on the outside in the radial direction. The first bridge portions 41 are provided in pairs on both sides of the first portion 3211 in the circumferential direction (outside in the circumferential direction). The first bridge portion 41 extends between the outer peripheral surface 328 of the rotor core 32 and the first magnet hole 321 .

The bridge portion 42 (hereinafter also referred to as “second bridge portion 42”) supports the second portion 3212 on the outside in the radial direction with respect to the third portion 3213. The second bridge portions 42 are provided in pairs on both sides of the second portion 3212 in the circumferential direction (outside in the circumferential direction). The second bridge portion 42 extends between the outer peripheral surface 328 of the rotor core 32 and the second magnet hole 322.

The bridge portion 43 supports the first portion 3211 with respect to the second portion 3212 on the d-axis.

The bridge portion 44 supports the second portion 3212 with respect to the third portion 3213 on the d-axis.

Note that the structure related to the bonded magnets 61 and 62 in the rotor core 32 is arbitrary and is not limited to the structure shown in FIGS. 2 and 3. For example, although the bonded magnet 61 is provided in the example shown in FIGS. 2 and 3, the bonded magnet 61 may be omitted as in the rotor 30A (rotor core 32A) according to the modified example shown in FIG. In this case, the first portion 3211 and the second portion 3212 are integrated, and the first bridge portion 41 substantially ceases to exist. Alternatively, an additional bonded magnet may be arranged radially inside the bonded magnet 62 in such a manner that the third portion 3213 becomes a magnetic path for the q-axis magnetic flux.

Next, a method for manufacturing the above-mentioned rotor core 32 (the same applies to the rotor core 32A) will be explained in detail.

FIG. 5 is a flowchart schematically showing the flow of the method for manufacturing the rotor 30 of this embodiment. 6 to 8 are explanatory diagrams of specific steps in the manufacturing method shown in FIG. 5.

The present manufacturing method first includes a preparation step (step S500) in which a workpiece for the rotor core 32 is prepared. Note that the rotor core 32 has the magnet holes 321 and 322, as described above. FIG. 6 is a plan view showing the initial workpiece (rotor core 32) prepared in the preparation process. FIG. 6A is an enlarged view of part Q1 in FIG. 6. At the stage of the preparation process, as shown in FIG. 6, nothing is placed in the magnet holes 321 and 322.

Next, the present manufacturing method includes a preparation step (step S502) of preparing the nonmagnetic materials 71 and 72. The non-magnetic materials 71 and 72 have sizes corresponding to the flux barrier portions in the magnet holes 321 and 322 into which they are inserted. FIG. 6A shows a space SC0 within the magnet hole 322 that will become the bonded magnet 62 described above, and other spaces SC1 and SC2 on both sides thereof (spaces that will become flux barrier parts). . In addition, in FIG. 6A, for convenience of illustration, the spaces SC0, SC1, and SC2 are shown slightly inside the hole edge 3221 of the magnet hole 322, but the hole edge 3221 is different from the spaces SC0, SC1. , bounds SC2.

Next, the manufacturing method includes an insertion step (step S504) of inserting the nonmagnetic materials 71 and 72 into the spaces SC1 and SC2 related to the flux barrier section, which are parts of the magnet holes 321 and 322, respectively. FIG. 7 is a diagram schematically showing the state of the nonmagnetic material 72 inserted in the insertion process (the state in the magnet hole 322).

Next, the manufacturing method includes a filling step (step S510) of filling the portions of the magnet holes 321 and 322 adjacent to the non-magnetic materials 71 and 72 with bonded magnet material using the manufacturing apparatus 100 described later. The filling process (step S510) may be performed with an orienting magnetic field applied. FIG. 8 is a diagram schematically showing the state of the bonded magnet material 90 filled in the filling process (the state in the magnet hole 322). Details of the filling process will be described later with reference to FIG. 9 and subsequent figures.

Next, the manufacturing method includes other post-processes (step S520). The post process may include, for example, a process of assembling the end plates 35A, 35B, the rotor shaft 34, etc.

Next, details of the filling process (step S510) in this manufacturing method and the configuration of the manufacturing apparatus 100 suitable for realizing the filling process will be described.

FIG. 9 is a flowchart schematically showing an example of the filling process (step S510). 10 to 13, FIG. 15, and FIG. 16 are explanatory diagrams of specific steps in the main filling process. FIG. 14 is an explanatory diagram of a movable contact mechanism 120A according to another example. 10 to 12, FIG. 15, and FIG. 16, a Z direction corresponding to the vertical direction is defined, and the Z1 side corresponds to the upper side and the Z2 side corresponds to the lower side. Further, in FIGS. 10 to 12 and 15, the central axis I of the manufacturing apparatus 100 is shown by a dashed line. Note that the manufacturing apparatus 100 may have a configuration that is substantially rotationally symmetrical about the central axis I.

The present filling process first includes a setting process (step S5102) in which the rotor core 32 (hereinafter also referred to as "work W") on which the non-magnetic materials 71 and 72 are assembled is set in the lower die 110 of the manufacturing apparatus 100. FIG. 10 is a cross-sectional view schematically showing a state in which the workpiece W is set on the lower die 110 of the manufacturing apparatus 100. Note that, in FIG. 10, a cross-sectional view of the workpiece W is shown that includes the rotating shaft 12 of the rotor core 32 and passes through the space SC0 (the same applies to FIG. 11, etc.). The work W may be set on the lower die 110 such that the rotation axis 12 of the rotor core 32 coincides with the central axis I of the manufacturing apparatus 100. Therefore, in the following description, the axial direction refers to the direction in which the rotating shaft (rotation center) 12 or the central axis I of the motor 1 extends, and the radial direction refers to the direction in which the rotating shaft 12 or the central axis I extends. Points in the radial direction. Therefore, the radially outer side refers to the side away from the rotating shaft 12 or the central axis I, and the radially inner side refers to the side facing the rotating shaft 12 or the central axis I. Further, the circumferential direction corresponds to the direction of rotation around the rotating shaft 12 or the central axis I.

In this embodiment, the manufacturing apparatus 100 includes a lower mold 110, a movable contact mechanism 120 (described later with reference to FIG. 12, etc.), an upper mold 130 (described later with reference to FIG. 11), and an injection molding device 140. (described later with reference to FIG. 15). The lower mold 110 has a support surface 111 in a horizontal plane, for example, and the workpiece W may be supported on the support surface 111 in such a manner that the axial end surface of the rotor core 32 is in surface contact with the support surface 111 .

Next, the main filling process includes a mold clamping process (step S5104) of lowering the upper mold 130 of the manufacturing apparatus 100 (see arrow R12 in FIG. 11) and pressing the rotor core 32 of the workpiece W in the axial direction. Specifically, in the main filling process, the upper mold 130 and the lower mold 110 are clamped against the workpiece W. In the mold clamping state, a state is realized in which the rotor core 32 of the workpiece W is pressurized with a targeted pressure force in the axial direction. Therefore, the axial distance between the upper die 130 and the lower die 110 in the clamped state can vary depending on variations in the axial dimension (i.e., stacking thickness) of the rotor core 32. FIG. 11 is a cross-sectional view schematically showing the mold clamping state. In this embodiment, the manufacturing apparatus 100 is realized in a manner including a mold clamping device for an injection molding machine related to an injection molding apparatus 140, and the upper mold 130 is placed in the space SC0, as schematically shown in FIG. It includes a structure such as a port for injecting the bonded magnet material 90.

Next, the main filling process includes a moving process (step S5106) in which the movable contact part 122 of the movable contact mechanism 120 is moved to a position where it contacts the outer circumferential surface of the rotor core 32, as schematically shown by arrow R13 in FIG. including. FIG. 12 is a cross-sectional view schematically showing the state after the moving process (the state in which the movable contact portion 122 is in contact with the outer peripheral surface of the rotor core 32). In this embodiment, the movable contact portion 122 is arranged between the upper mold 130 and the lower mold 110 in the vertical direction. The movable contact portion 122 is configured to be movable in translation toward the central axis I in a horizontal plane. In this embodiment, the movable contact portion 122 is supported by the lower mold 110 in a manner that it can slide on the support surface 111 (horizontal surface) of the lower mold 110, as schematically shown in FIGS. 10 to 12, etc. be done. However, in a modified example, the movable contact portion 122 may be supported by the lower mold 110 in such a manner that it can slide on the support surface 131 (horizontal surface) of the upper mold 130.

The movable contact portion 122 has a contact position where it contacts the radially outer surface (outer circumferential surface) of the rotor core 32 of the workpiece W (see FIG. 12), and a non-contact position where it contacts the radially outer surface of the rotor core 32 of the workpiece W (see FIG. 12). It is movable between the contact position (see FIGS. 10 and 11). For this purpose, the movable abutment mechanism 120 includes an actuator 124 for the movement of the movable abutment part 122. The type of actuator 124 is arbitrary, and may be, for example, an air cylinder or a motor. Note that, when the actuator 124 is a motor, the movable contact mechanism 120 may include a mechanism (for example, a screw mechanism) that converts rotation of the motor into linear movement.

In the example shown in FIG. 10 and the like, the actuator 124 of the movable contact mechanism 120 generates a load in a horizontal plane and in a direction toward the central axis I, but the present invention is not limited to this. For example, as in another example shown in FIG. 14, an actuator 124A that generates a load in the vertical direction may be used. In this case, as schematically shown in FIG. 14, the movable contact mechanism 120A moves vertically based on the vertical load from the actuator 124A (see arrow R140) in a horizontal plane and in a direction toward the central axis I. (see arrow R141).

In this embodiment, the movable contact portion 122 is movable even in the mold clamping state described above. That is, in the mold clamping state, the movable contact portion 122 is not held between the upper mold 130 and the lower mold 110, and is still capable of translational movement in the horizontal plane toward the central axis I. For this purpose, the movable abutment part 122 may have an upper surface 1220 (see FIG. 12) located below the upper mold 130. That is, the upper surface 1220 of the movable contact portion 122 has a clearance Δ in the vertical direction with respect to the support surface 131 of the upper mold 130. The size of the clearance Δ is an arbitrary value larger than 0, but may be adjusted according to variations in the vertical dimension (that is, stacking thickness) of the rotor core 32. That is, even when the vertical dimension of the rotor core 32 reaches the lower limit value, the clearance Δ significantly larger than 0 may be ensured.

In this way, according to this embodiment, by making the movable contact portion 122 movable even in the mold clamping state, undesirable radial outward deformation of the rotor core 32 due to injection pressure during injection molding can be avoided. can be prevented. In addition, in the mold clamping state, since the clearance Δ is secured between the upper mold 130 and the movable contact portion 122 as described above, the rotor core 32 is aimed regardless of the movement of the movable contact portion 122. The axially pressurized state can be maintained during the mold clamping state. Therefore, according to this embodiment, during injection molding, it is possible to press the rotor core 32 in the axial direction with a targeted pressure while preventing undesirable deformation of the rotor core 32 radially outward due to injection pressure. becomes.

The movable contact portion 122 preferably makes surface contact with the outer circumferential surface 328 of the rotor core 32 at the contact position. Further, preferably, the movable contact portion 122 is in surface contact with the outer circumferential surface 328 of the rotor core 32 over the entire axial length of the rotor core 32 at the contact position. Thereby, as will be described later with reference to FIGS. 16 and 17, it is possible to effectively reduce stress concentration in the bridge portions 41 and 42 that may occur due to injection pressure. Furthermore, the movable contact portion 122 may contact the outer circumferential surface 328 of the rotor core 32 over the entire circumference in the circumferential direction around the central axis I. FIG. 13 is a diagram schematically showing the contact state of the movable contact portion 122 in a partial range in the circumferential direction, and is a cross-sectional view taken along a plane perpendicular to the axial direction. As shown in FIG. 13, the movable contact portion 122 may contact the entire outer circumferential surface 328 of the rotor core 32 in a circumferential range where the bridge portions 41 and 42 are arranged. In the example shown in FIG. 13, jigs 125 are provided on both sides of the movable contact portion 122 in the circumferential direction. Note that the jig 125 may have an abutment surface at a radial position corresponding to the maximum allowable outer diameter of the rotor core 32. In this case, the movable contact portion 122 functions radially inside the contact surface of the jig 125.

In the main filling process, the moving process (step S5106) is executed after the mold clamping process (step S5104), but may be executed before the mold clamping process (step S5104).

Next, the manufacturing method includes an injection molding step (step S5108) of injecting bonded magnet material into portions of the magnet holes 321 and 322 adjacent to the nonmagnetic materials 71 and 72. FIG. 15 is a cross-sectional view schematically showing the state during the injection molding process. In FIG. 15, an arrow R15 schematically indicates the flow state of the bonded magnet material 90 into the space SC0.

This manufacturing method includes a curing process (step S5110) for curing the bonded magnet material 90, subsequent to the injection molding process (step S5108). The curing process may be a heating process to thermally harden the bonded magnet material 90.

This manufacturing method includes, in parallel with the injection molding process (step S5108), an adjustment process (step S5112) of adjusting the position of the movable contact portion 122 (the position in the radial direction with respect to the central axis I). The adjustment step includes maintaining the position of the movable abutting portion 122 at the abutting position. The contact position with respect to the central axis I (or the rotation axis 12 of the rotor core 32) may be a position corresponding to the outer diameter of the rotor core 32. Note that the contact position to be adjusted does not need to be exactly one point, and may be defined as a specific position range (range in which the contact state is maintained) according to the tolerance related to the outer diameter of the rotor core 32. . For example, the adjustment step may include maintaining the position of movable abutment part 122 so that the position of movable abutment part 122 does not deviate from within a specific position range. In order to be able to cope with such variations in the contact position, the portion of the upper mold 130 that contacts the axial end surface of the rotor core 32 has an outer diameter that is slightly smaller than the lower limit of the possible outer diameter of the rotor core 32. diameter (for example, an outer diameter smaller by about 0.1 mm to 1 mm).

The adjustment step (step S5112) applies a radially inward pressing force along the radial direction to the radially outer surface of the workpiece (i.e., the outer circumferential surface 328 of the rotor core 32) via the movable contact portion 122. It may include that. In this case, the pressing force may be a pressing force for maintaining the position of the movable contact portion 122 within a specific position range. For example, the pressing force may be changed in conjunction with a change in the injection pressure of injection molding during the injection molding process (step S5108).

Note that the adjustment process (step S5112) may also be performed during the curing process (step S5110) subsequent to the injection molding process (step S5108).

Next, the manufacturing method includes a step of moving the upper die 130 and the movable contact portion 122 to the initial position when the bonded magnet material 90 is hardened (step S5114). Note that the initial position of the movable contact portion 122 corresponds to the above-mentioned non-contact position (see FIGS. 10 and 11).

Next, the present manufacturing method takes out the workpiece (step S5116) and ends.

Next, further effects of this embodiment will be described with reference to FIGS. 16 and 17.

FIG. 16 is a diagram schematically showing the state of force (reaction force, etc.) generated by the non-magnetic material 72 during the injection molding process (step S5108) when viewed in the axial direction. FIG. 17 is an explanatory diagram of the bridge protection function by the movable contact part 122, and shows the state of the pressing force of the movable contact part 122 in the axial direction during the injection molding process (and adjustment process) in the same view as FIG. FIG.

As shown in FIG. 16, when the bonded magnet material 90 is injection molded, the bonded magnet material 90 is filled into the space SC0 with fluid pressure according to the injection pressure. At this time, a pressure corresponding to the injection pressure is generated in the nonmagnetic material 72 from the bonded magnet material 90, as schematically shown as pressure p91 in FIG. Such pressure p91 acts on the bridge portion 42 (the same applies to the bridge portion 41) and becomes a cause of stress in the bridge portion 42.

On the other hand, according to this embodiment, as described above, the radially inward pressing force from the movable contact portion 122 is reduced to the injection pressure, as schematically shown by arrow F13 in FIGS. 15 and 17. It can act as a drag force against As a result, among the forces that the non-magnetic bodies 71 and 72 receive from the bonded magnet material due to the injection pressure, the force that is transmitted to the bridge parts 41 and 42 via the non-magnetic bodies 71 and 72 (towards the outside in the radial direction) force) can be reduced. As a result, stress concentration in the bridge portions 41 and 42 that may occur due to injection pressure can be reduced. In other words, even if the injection pressure of the bonded magnet material is increased, the stress concentration in the bridge parts 41 and 42 can be reduced, so although the fluidity is relatively low (therefore it is necessary to inject at a relatively high injection pressure), the magnetic It is also possible to use a bonded magnet material with good characteristics (for example, a bonded magnet material with a high content of magnetic particles), and it is also possible to improve the magnetic characteristics of the motor 1.

By the way, in a configuration in which the bonded magnets 61 and 62 are arranged symmetrically with respect to the d-axis as in the motor 1 according to this embodiment (see FIGS. 3 and 4), the portion of the first portion 3211 on the d-axis also has the following characteristics: The bonded magnet material 90 tends to deform outward in the radial direction due to injection pressure. In consideration of this point, in a modified example, for example, as shown in FIG. 18, another movable contact part 122B may be provided which has a different contact range with respect to the rotor core 32 than the movable contact part 122. The movable contact portion 122B contacts the rotor core 32 in a circumferential range centered on the d-axis. In this case, the movable contact portion 122B can apply the same effect as the movable contact portion 122 to the bridge portions 41 and 42 to the portion of the first portion 3211 of the rotor core 32 on the d-axis. That is, it is possible to reduce stress concentration on the d-axis portion of the first portion 3211 that may occur due to injection pressure. In the example shown in FIG. 18, both the movable contact portion 122 and the movable contact portion 122B are provided, but only the movable contact portion 122B may be provided.

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

For example, in the embodiment described above, the movable contact mechanism 120 (as well as the movable contact mechanism 120A) is applied in the filling process (injection molding process) of the bonded magnet material 90, but the present invention is not limited to this. The movable contact mechanism 120 (the same applies to the movable contact mechanism 120A) can also be applied to, for example, an injection molding process (not shown) of a resin material for fixing a sintered magnet in a magnet hole. Furthermore, in the above embodiment, the nonmagnetic materials 71 and 72 are prepared in the preparation step (step S502), but they may also be formed by injection molding prior to the filling step (injection molding step) with the bonded magnet material 90. good. In this case, the movable contact mechanism 120 (the same applies to the movable contact mechanism 120A) can also be applied to an injection molding process (not shown) for the non-magnetic materials 71 and 72.

1... Motor (rotating electrical machine), 32, 32A... Rotor core (rotor core for rotating electrical machine, laminated core), 3211... First part (rotor core part), 3212... Second part (rotor core part) , 3213... Third part (rotor core part), 321, 322... Magnet hole, 41, 42... Bridge part (outer circumferential bridge), 71, 72... Non-magnetic material, 61, 62...・Bonded magnet, 100... Manufacturing equipment (rotor manufacturing equipment for rotating electric machines), 130... Upper mold (mold equipment), 110... Lower mold (mold equipment), 122... Movable contact Part, 140... Injection molding device (injection device), W... Workpiece

Claims (8)

A mold device capable of setting a workpiece of a rotor core for a rotating electric machine equipped with a magnet hole;
a movable contact portion disposed in the mold device and movable between a contact position in which it contacts a radially outer surface of the workpiece and a non-contact position away from the radially outer surface of the workpiece; and,
an injection device capable of filling the magnet hole in the workpiece with an injection molding material, and the movable contact portion is configured to press the workpiece set in the mold device during injection molding by the injection device. A rotor manufacturing device for a rotating electrical machine that is movable along the radial direction of the rotor. The workpiece has an outer circumferential bridge adjacent to the radially outer side of the magnet hole, the outer circumferential bridge connecting rotor core parts separated by the magnet hole,
The rotor manufacturing apparatus for a rotating electrical machine according to claim 1, wherein the movable contact portion is capable of contacting the workpiece in a circumferential range in which the outer circumferential bridge is arranged, out of the entire circumference of the workpiece. The rotor manufacturing for a rotating electrical machine according to claim 1, wherein the movable contact portion is capable of contacting the workpiece in a circumferential range centered on the d-axis related to each magnetic pole of the rotating electrical machine, out of the entire circumference of the workpiece. Device. The rotor core for a rotating electrical machine is in the form of a laminated iron core,
The mold device includes an upper mold and a lower mold that are relatively movable in the vertical direction, and the workpiece can be set between the upper mold and the lower mold in the vertical direction,
The injection device is capable of filling the injection molding material in a mold clamped state by the upper mold and the lower mold of the mold device,
The movable contact portion is arranged between the upper mold and the lower mold in the vertical direction, and is movable along the radial direction of the workpiece when the mold device is in a clamped state. A rotor manufacturing device for a rotating electrical machine as described in . 5. The rotor manufacturing device for a rotating electrical machine according to claim 4, wherein the movable contact portion has a gap with respect to the upper mold or the lower mold in the vertical direction when the mold device is in a clamped state. The movable contact portion is supported by the upper mold or the lower mold in such a manner that it can translate toward the central axis of the workpiece on a horizontal surface of the upper mold or a horizontal surface of the lower mold. Item 4. The rotor manufacturing device for a rotating electric machine according to item 4. a setting step of setting a workpiece of a rotor core for a rotating electrical machine having a magnet hole in a mold device;
After the setting step, by moving the movable contact portion, a transition is made from a non-contact state where the movable contact portion is away from the radially outer surface of the workpiece to a contact state where the movable contact portion is in contact with the radially outer surface of the workpiece. a moving process of
an injection molding step of filling the magnet hole in the workpiece with an injection molding material in the contact state of the movable contact part;
executed in parallel with the injection molding step, and adjusting the position of the movable contact portion so that the movable contact portion is maintained in the contact state, or adjusting the position of the movable contact portion in the radial direction of the workpiece in the contact state A method for manufacturing a rotor for a rotating electric machine, including an adjustment step of adjusting a pressing force applied to an outer surface. The workpiece has an outer circumferential bridge adjacent to the radially outer side of the magnet hole, the outer circumferential bridge connecting rotor core parts separated by the magnet hole,
8. The rotor manufacturing method for a rotating electric machine according to claim 7, wherein the contact state includes a state in which the movable contact portion contacts a circumferential range in which the outer peripheral bridge is arranged, out of the entire circumference of the workpiece. .