Brushless motor and method of manufacturing rotor

Abstract

To provide a method of manufacturing a brushless motor and a rotor capable of improving assembly workability.SOLUTION: The first annular protrusion 75 that supports the axial front end portion of the magnet 63 is provided at the portion of the other side surface 74 of the stopper plate 70 facing the magnet 63, the second annular protrusion 76 that supports the axial front end portion of the rotor main body 62 is provided at the portion of the other side surface 74 of the stopper plate 70 facing the rotor main body 62, and the communication path 75a that communicates the radially inner side and the radially outer side of the first annular protrusion 75 is provided in the first annular protrusion 75. At the time of assembling the rotor 60, air gently flows through the 75a of the communication path, and the adhesive protruding into the first adhesive accommodating recess 77 on the radially inner side of the first annular protrusion 75 does not vigorously protrude into the second adhesive accommodating recess 78 on the radially outer side of the first annular protrusion 75. Therefore, the assembling workability can be improved.SELECTED DRAWING: Figure 5

Description

[Technical Field]

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

[0002] Conventionally, brushless motors include a stator fixed to a case and a rotor that rotates relative to the stator. Such brushless motors are so-called inner rotor brushless motors, and are used as drive sources for electric brake devices, power steering devices, and the like that are installed in vehicles such as automobiles.

[0003] For example, Patent Document 1 describes a brushless motor that can be used as a drive source for an electric brake device. The rotor that forms the brushless motor described in Patent Document 1 has a rotor core, a shaft fixed to the rotor core, a magnet cover attached to the shaft and abutting against the rotor core, and a ring magnet attached to the rotor core and abutting against the magnet cover. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6997037 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the technology described in Patent Document 1, an annular outer rib is provided radially outside the main body portion that forms the magnet cover, and the entire axial end of this outer rib supports the end of the ring magnet.

[0006] As a result, when assembling the rotor, the ring magnet is attached to the rotor core, and the end of the ring magnet is brought into full contact with the axial end of the outer rib, and at that moment, the air inside the outer rib in the radial direction is forcefully expelled to the outside of the outer rib in the radial direction. As a result, the adhesive that has spilled out of the adhesive pockets spurts out to the outside of the outer rib in the radial direction, posing a problem that the adhesive must be wiped off.

[0007] An object of the present invention is to provide a method for manufacturing a brushless motor and a rotor that can improve assembly workability. [Means for solving the problem]

[0008] The brushless motor of the present invention is a brushless motor having a rotor that rotates relative to a stator, wherein the rotor has a rotor body, a rotating shaft that is rotated by the rotor body, a magnet fixed to the outer periphery of the rotor body with an adhesive, and a positioning member that is attached to the rotating shaft and positions the magnet and the rotor body in the axial direction of the rotating shaft, wherein a first annular convex portion that supports the axial tip of the magnet is provided at the portion of the positioning member facing the magnet, and a second annular convex portion that supports the axial tip of the rotor body is provided at the portion of the positioning member facing the rotor body, and the first annular convex portion has a communicating passage that connects the radial inside and outside of the first annular convex portion.

[0009] A method for manufacturing a rotor according to the present invention is a method for manufacturing a rotor having a rotor body, a rotating shaft rotated by the rotor body, a magnet adhesively fixed to the outer periphery of the rotor body, and a positioning member attached to the rotating shaft and positioning the magnet and the rotor body in the axial direction of the rotating shaft, wherein a first annular convex portion supporting an axial tip end of the magnet is provided on a portion of the positioning member facing the magnet, and a second annular convex portion supporting an axial tip end of the rotor body is provided on a portion of the positioning member facing the rotor body, and a communication passage is provided in the first annular convex portion, connecting a radial inside and a radial outside of the first annular convex portion, and a sub-assembly is formed by abutting the axial tip end of the magnet against the first annular convex portion. and a first jig setting process for setting the sub-assembly in a first jig; a second jig setting process for setting the axial base end of the rotating shaft in a second jig provided coaxially with the first jig; an adhesive application process for applying adhesive to the magnet and the rotor body; an insertion process for moving at least one of the first jig and the second jig so that the axial tip end side of the rotating shaft faces the axial base end side of the magnet and inserting the axial tip end side of the rotor body into the axial base end side of the magnet; and a bonding process for distributing the adhesive between the rotor body and the magnet while discharging air inside the magnet to the outside of the magnet via the communication passage and abutting the axial tip end of the rotor body against the second annular convex portion. [Effects of the Invention]

[0010] According to the present invention, when assembling the rotor, air flows gently through the communication passage provided in the first annular convex portion of the positioning member. This prevents adhesive that has spilled out radially inward from spilling out radially outward from the first annular convex portion. This improves the ease of assembly. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view showing an example of use of the brushless motor of the first embodiment. [Figure 2] 2 is a perspective view of the brushless motor of FIG. 1 as seen from the bracket side. [Figure 3] 2 is a perspective view of the brushless motor of FIG. 1 as seen from the case side. [Figure 4] FIG. 2 is a cross-sectional view showing the internal structure of the brushless motor of FIG. [Figure 5] FIG. 5 is a cross-sectional view showing the rotor alone in FIG. 4. [Figure 6] FIG. 6 is a perspective view of the stopper plate of FIG. 5 viewed from the sensor magnet side. [Figure 7] FIG. 6 is a perspective view of the stopper plate of FIG. 5 viewed from the rotor core side. [Figure 8] FIG. 6 is a perspective view of the rotor of FIG. 5 exploded into two subassemblies. [Figure 9] 6 is a diagram illustrating a first assembly procedure for the rotor of FIG. 5. FIG. [Figure 10] 6 is a diagram illustrating a second assembly procedure for the rotor of FIG. 5. FIG. [Figure 11] 6 is a diagram illustrating a third assembly procedure of the rotor shown in FIG. 5. FIG. [Figure 12] 6 is a diagram illustrating a fourth step in assembling the rotor of FIG. 5. FIG. [Figure 13] 6 is a diagram illustrating a fifth step in assembling the rotor of FIG. 5. FIG. [Figure 14] FIG. 10 is a cross-sectional view showing the rotor alone of a brushless motor according to a second embodiment. [Figure 15] FIG. 15 is a perspective view of the stopper plate of FIG. 14 viewed from the sensor magnet side. [Figure 16] FIG. 15 is a perspective view of the stopper plate of FIG. 14 viewed from the rotor core side. [Figure 17] FIG. 15 is a perspective view of the rotor in FIG. 14 disassembled into two subassemblies. [Figure 18] 15A and 15B are views corresponding to FIG. 11 and illustrating the procedure for assembling the rotor of FIG. 14. [Figure 19] 15A and 15B are diagrams corresponding to FIG. 12 and illustrating the assembly procedure of the rotor of FIG. 14. DETAILED DESCRIPTION OF THE INVENTION

[0012] [Embodiment 1] Hereinafter, the first embodiment of the present invention will be described in detail with reference to the drawings.

[0013] FIG. 1 is a perspective view showing an example of use of the brushless motor of embodiment 1, FIG. 2 is a perspective view of the brushless motor of FIG. 1 seen from the bracket side, FIG. 3 is a perspective view of the brushless motor of FIG. 1 seen from the case side, FIG. 4 is a cross-sectional view showing the internal structure of the brushless motor of FIG. 1, FIG. 5 is a cross-sectional view of the rotor alone of FIG. 4, FIG. 6 is a perspective view of the stopper plate alone of FIG. 5 seen from the sensor magnet side, and FIG. 7 is a perspective view of the stopper plate alone of FIG. 5 seen from the rotor core side.

[0014] 8 is an oblique view of the rotor in FIG. 5 disassembled into two subassemblies, FIG. 9 is a diagram explaining assembly procedure 1 for the rotor in FIG. 5, FIG. 10 is a diagram explaining assembly procedure 2 for the rotor in FIG. 5, FIG. 11 is a diagram explaining assembly procedure 3 for the rotor in FIG. 5, FIG. 12 is a diagram explaining assembly procedure 4 for the rotor in FIG. 5, and FIG. 13 is a diagram explaining assembly procedure 5 for the rotor in FIG. 5.

[0015] [Brushless motor] 1, brushless motor 10 drives driven object 11, which is shown schematically by a two-dot chain line. In this embodiment, driven object 11 is an electric brake device mounted on a vehicle such as an automobile. Specifically, brushless motor 10 drives a piston of the electric brake device to press brake pads against a disc rotor.

[0016] As shown in Figures 1 to 4, brushless motor 10 includes a metal case 20. Case 20 is formed into a cylindrical shape with a bottom by deep drawing a metal plate or the like. Case 20 includes a cylindrical portion 21, and a bottom wall portion 22 is provided on the axial base end side of cylindrical portion 21 (lower side in Figure 4). Meanwhile, an opening 23 is provided on the axial tip side of cylindrical portion 21 (upper side in Figure 4).

[0017] Furthermore, a flange portion 24 protruding radially outward is provided on the opening 23 side of the cylindrical portion 21. The flange portion 24 is attached to the axial base end side (the lower side in FIG. 4) of a resin bracket 40 with a total of three first screw members S1. In this way, the opening 23 of the case 20 is closed by the bracket 40.

[0018] [Stator] As shown in Fig. 4, a stator 25 is housed inside the case 20. Specifically, the stator 25 is fixed to the radially inner side of the cylindrical portion 21 by press-fitting or the like. The stator 25 includes a stator core 26 formed in a generally cylindrical shape, and the stator core 26 is formed by laminating a plurality of thin steel plates. The stator core 26 has a core body 26a formed in a generally cylindrical shape and a plurality of teeth 26b protruding radially inward from the core body 26a.

[0019] Resin insulators 27 are attached to each of the plurality of teeth 26b, and coils 28 consisting of U-phase, V-phase, and W-phase are wound around the outside of the insulators 27 in a predetermined winding manner and with a predetermined number of turns. That is, the three-phase coils 28 are wound around each of the plurality of teeth 26b via the insulators 27, which function as insulators. The three-phase coils 28 are arranged alternately in the circumferential direction of the stator 25 as U-phase, V-phase, W-phase, U-phase, V-phase, W-phase...

[0020] An annular busbar unit 29 is attached to the axial tip side (upper side in FIG. 4) of the stator 25. The busbar unit 29 includes a total of three conductive members 30 corresponding to the U-phase, V-phase, and W-phase, and ends of the three-phase coils 28 are electrically connected to one ends of these conductive members 30, respectively.

[0021] On the other hand, a power terminal (not shown) to which a vehicle-side power connector (not shown) is connected is electrically connected to the other end of each conductive member 30. Here, the power terminal is embedded inside a power connector connection portion CN1 that is integrally provided with the bracket 40, and the vehicle-side power connector can be connected to this power connector connection portion CN1.

[0022] [bracket] Here, bracket 40 has the function of fixing brushless motor 10 to driven object 11 (see FIG. 1). Bracket 40 is an injection-molded product made by injection molding a resin material such as molten plastic, and closes opening 23 of case 20 as shown in FIG.

[0023] The bracket 40 has a partition wall portion 41 formed in a substantially circular plate shape. The partition wall portion 41 has a function of separating the case 20 side (lower side in FIG. 4) from the driven object 11 side (upper side in FIG. 4), and an insertion tube portion 42 is integrally provided in the center of the partition wall portion 41, through which the axial tip side (upper side in FIG. 4) of the rotation shaft 61 is inserted.

[0024] A bearing holder 43 formed into a generally cup shape by pressing a steel plate or the like is provided on the radially inner side of the insertion cylindrical portion 42. Specifically, the radially outer side of the bearing holder 43 is fixed to the radially inner side of the insertion cylindrical portion 42. The bearing holder 43 holds a first ball bearing BB1 that rotatably supports the axial tip side of the rotating shaft 61. An annular fixing plate 44 is provided on the axial base end side of the first ball bearing BB1 (the lower side in FIG. 4) to prevent the first ball bearing BB1 from falling off the bearing holder 43.

[0025] Furthermore, the insertion cylindrical portion 42 has a function of holding a sensor board 50. Specifically, the sensor board 50 is provided on the axial base end side (lower side in FIG. 4) of the insertion cylindrical portion 42, and the sensor board 50 is fixed to the axial base end side of the insertion cylindrical portion 42 with a fixing screw SC. Here, the sensor board 50 is disposed on the axial base end side (lower side in FIG. 4) of the bracket 40, between a first ball bearing BB1 and a sensor magnet SM provided on the rotation shaft 61. Hall elements 51 corresponding to the U phase, V phase, and W phase are mounted on the sensor board 50, and these Hall elements 51 face the sensor magnet SM in the axial direction of the rotation shaft 61.

[0026] One end of a sensor terminal (not shown) is electrically connected to the sensor board 50, and the sensor terminal is embedded inside a sensor connector connection portion CN2 (see FIGS. 1 to 3) that is integrally provided on the bracket 40. A sensor connector (not shown) on the vehicle side can be connected to the sensor connector connection portion CN2.

[0027] As shown in Fig. 4, a cylindrical wall portion 45 that forms the outer shell of the bracket 40 is provided on the radially outer side of the insertion cylindrical portion 42. The cylindrical wall portion 45 is thicker than the insertion cylindrical portion 42 and is provided integrally with the partition wall portion 41 on the radially outer side. The cylindrical wall portion 45 is arranged coaxially with the insertion cylindrical portion 42 and extends in the axial direction of the rotation shaft 61. A case-facing surface 45a that faces the flange portion 24 of the case 20 is provided on the axial base end side (lower side in Fig. 4) of the cylindrical wall portion 45. Meanwhile, a driven object-facing surface 45b that faces the driven object 11 is provided on the axial tip side (upper side in Fig. 4) of the cylindrical wall portion 45.

[0028] A total of three driven object fixing portions 46 are integrally formed on the cylindrical wall portion 45. Metal collars CL are attached to these driven object fixing portions 46. This allows the brushless motor 10 to be firmly fixed to the driven object 11 without damaging the resin driven object fixing portions 46. A second screw member S2 for fixing the brushless motor 10 to the driven object 11 is inserted into the collar CL.

[0029] Additionally, a power supply connector connection portion CN1 and a sensor connector connection portion CN2 are integrally provided on the radially outer side of the cylindrical wall portion 45. The power supply connector connection portion CN1 and the sensor connector connection portion CN2 are each formed in a substantially rectangular box shape. The vehicle-side power supply connector and the sensor connector are inserted into one longitudinal side (the upper left side in FIG. 2) of the power supply connector connection portion CN1 and the sensor connector connection portion CN2, respectively.

[0030] Furthermore, a total of three case fixing portions 47 are integrally formed on the cylindrical wall portion 45. These case fixing portions 47 are portions to which the flange portion 24 of the case 20 is fixed, and each case fixing portion 47 is provided with a cap nut 48. First screw members S1 that fix the case 20 to the bracket 40 are screwed into each of these cap nuts 48.

[0031] 3, a total of three case fixing portions 47 (first screw members S1) are arranged side by side at equal intervals (120-degree intervals) in the circumferential direction of the cylindrical wall portion 45, and the case fixing portions 47 are disposed between adjacent driven object fixing portions 46 (second screw members S2). This distributes the tightening load of the first and second screw members S1, S2 in the circumferential direction of the bracket 40, suppressing damage to the bracket 40 due to stress concentration.

[0032] A fitting tubular portion 49 is integrally formed on the axial base end side of the bracket 40. The fitting tubular portion 49 is fitted into the opening 23 of the case 20, and a first annular seal SL1 made of an elastic material such as rubber is attached to the radial outside of the fitting tubular portion 49. The first annular seal SL1 provides a seal between the bracket 40 and the case 20.

[0033] In contrast, an annular recess 45c is provided on the axial tip side of the bracket 40. A second annular seal SL2 made of an elastic material such as rubber is attached to the annular recess 45c. The second annular seal SL2 seals the gap between the bracket 40 and the driven object 11.

[0034] [Rotor] 4, 5, and 8, brushless motor 10 includes rotor 60 that rotates relative to stator 25. Rotor 60 includes a rotating shaft 61, a rotor body 62, a magnet 63, a magnet support member 64, and a stopper plate 70.

[0035] The rotating shaft 61 is formed into a stepped rod shape by machining a round steel bar or the like. The rotating shaft 61 has a large-diameter portion 61a and a medium-diameter portion 61b. A rotor body 62, which is formed into a generally cylindrical shape by laminating multiple thin steel plates, is fixed to the outer periphery of the large-diameter portion 61a. Specifically, the inner periphery of the rotor body 62 is provided with multiple mating protrusions CP extending in the axial direction of the rotor body 62 and arranged at equal intervals in the circumferential direction (see FIG. 8). These mating protrusions CP are press-fitted into the outer periphery of the large-diameter portion 61a. As a result, the two are firmly fixed to each other, and the rotating shaft 61 rotates when the rotor body 62 rotates. Note that a clearance CR is defined between the rotor body 62 and the large-diameter portion 61a at a location where no mating protrusions CP are provided (see FIG. 5). Furthermore, the axial base end side (right side in FIG. 5) of the large diameter portion 61a and the axial base end side (right side in FIG. 5) of the rotor body 62 are aligned in the same axial position so as to be flush with each other.

[0036] A bearing mounting portion 61c is provided on the axial base end side of the large diameter portion 61a. The bearing mounting portion 61c has a smaller diameter than the large diameter portion 61a and the same diameter as the medium diameter portion 61b. The axial length of the bearing mounting portion 61c is approximately 1 / 5 of the axial length of the large diameter portion 61a. The bearing mounting portion 61c is rotatably supported by a second ball bearing BB2 mounted on the bottom wall portion 22 of the case 20. In this way, the rotating shaft 61 is rotatably supported by a total of two ball bearings, first and second ball bearings BB1 and BB2. The first and second ball bearings BB1 and BB2 are both the same ball bearing.

[0037] A cylindrical magnet 63 is adhered and fixed to the outer periphery of rotor body 62 with adhesive GL (see FIGS. 8 to 13). In other words, brushless motor 10 is a surface permanent magnet type brushless motor in which magnet 63 is attached to the surface of rotor body 62. The axial tip end side (left side in FIG. 5) of rotor body 62 and the axial tip end side (left side in FIG. 5) of magnet 63 are aligned in the same axial position so that they are flush with each other.

[0038] The outer periphery of the magnet 63 is covered by a cylindrical magnet support member 64 made of a stainless steel plate or the like. The magnet support member 64 includes a disk-shaped bottom wall 64a that abuts against the axial base end side of the rotor body 62, and a cylindrical covering wall 64b that is integral with the outer edge of the bottom wall 64a and extends in the axial direction of the rotating shaft 61. The covering wall 64b covers the surface of the magnet 63, and a crimped portion 64c that is reduced in diameter radially inward is provided on the axial tip side of the covering wall 64b (left side in FIG. 5).

[0039] The crimped portion 64c is a portion that is formed when assembling the rotor 60, and by forming the crimped portion 64c, the magnet support member 64 is fixed to the magnet 63. Note that a resin stopper plate 70 is provided between the axial tip end side of the magnet 63 and the crimped portion 64c to prevent the crimping force that is applied to the magnet 63 when the crimped portion 64c is formed.

[0040] In this way, by providing the magnet support member 64, the air gap AG (minute gap) between the rotor body 62 and the stator 25 is ensured with high precision even when the rotor 60 rotates at high speed. The stopper plate 70 also has a positioning function that aligns the axial tip ends of the rotor body 62 and the magnet 63 so that they are flush with each other in the axial direction of the rotating shaft 61.

[0041] Here, the length L1 of the rotor body 62 in the axial direction of the rotating shaft 61 is longer than the length L2 of the magnet 63 in the axial direction of the rotating shaft 61 (L1>L2). As a result, a step portion DS is formed on the axial base end side of the rotor body 62 and the magnet 63, and an annular space SP is formed between the step portion DS and the magnet support member 64. The annular space SP can contain adhesive GL (see FIGS. 8 to 13) that has spilled out from between the rotor body 62 and the magnet 63. Therefore, the spilled adhesive GL does not bulge outward in the radial direction of the magnet support member 64, and an air gap AG is reliably secured.

[0042] Additionally, an annular sensor magnet SM is attached to the outer periphery of the medium diameter portion 61b via a sensor bracket 65. Specifically, the sensor magnet SM is disposed approximately in the center of the rotating shaft 61 in the axial direction. The sensor magnet SM is used to detect the rotational state of the rotating shaft 61, and rotates as the rotating shaft 61 rotates. N poles and S poles are arranged alternately around the circumferential direction of the sensor magnet SM, and a Hall element 51 facing the sensor magnet SM detects changes in the magnetic poles of the sensor magnet SM. This allows an on-board controller (not shown) to grasp the rotational state (rotation direction, rotation speed, etc.) of the rotating shaft 61 and optimally control the rotation of the rotor 60 based on this.

[0043] Furthermore, a pinion gear portion 61d is integrally provided on the axial tip side (left side in FIG. 5) of medium diameter portion 61b. Pinion gear portion 61d forms the output portion of brushless motor 10. Specifically, in this embodiment, pinion gear portion 61d is connected to a feed screw shaft (not shown) that moves a piston of an electric brake device (driven object 11) forward and backward so as to be able to transmit power.

[0044] [Stopper plate] 5 to 7, the stopper plate 70 is formed in a generally circular plate shape by injection molding a resin material such as plastic. The outer diameter of the stopper plate 70 is the same as or approximately the same as the outer diameter of the magnet 63. A fitting hole 70a is provided in the center of the stopper plate 70, and a portion of the large diameter portion 61a closer to the medium diameter portion 61b is fitted into the fitting hole 70a. In other words, the stopper plate 70 is attached coaxially to the rotation shaft 61.

[0045] Here, the stopper plate 70 has a function of preventing the crimping force from being transmitted to the magnet 63 when crimping the crimped portion 64c, and a positioning function of positioning the axial tip ends of the magnet 63 and the rotor body 62 so that they are flush with each other. In other words, the stopper plate 70 positions the magnet 63 and the rotor body 62 in the axial direction of the rotating shaft 61, and corresponds to the positioning member of the present invention.

[0046] The stopper plate 70 includes a large-diameter disk portion 71. A thick-walled cylindrical portion 73 is integrally provided on one side surface 72 (the surface on the pinion gear portion 61d side) of the large-diameter disk portion 71 in the axial direction of the rotary shaft 61. The axial thickness of the thick-walled cylindrical portion 73 is larger than the axial thickness of the large-diameter disk portion 71, specifically, approximately four times the thickness. In contrast, the outer diameter of the thick-walled cylindrical portion 73 is smaller than the outer diameter of the large-diameter disk portion 71. As a result, a recess G is formed on the outer periphery of the one side surface 72 of the large-diameter disk portion 71, and the crimped portion 64c fits into the recess G.

[0047] A total of six recessed portions 73a are provided in the thick-walled cylindrical portion 73. A total of six recessed grooves 73b are also provided in the thick-walled cylindrical portion 73. The recessed grooves 73b are provided between adjacent recessed portions 73a in the circumferential direction of the thick-walled cylindrical portion 73, and are recessed in the same direction as the recessed portions 73a in the axial direction of the thick-walled cylindrical portion 73. The depth of the recessed grooves 73b is shallower than the depth of the recessed portions 73a.

[0048] These recessed portions 73a and recessed grooves 73b are arranged at equal intervals (60-degree intervals) around the circumference of the thick-walled cylindrical portion 73. Providing the recessed portions 73a and recessed grooves 73b in this manner reduces the volume of the thick-walled cylindrical portion 73, thereby reducing the weight of the stopper plate 70 and preventing distortion of the stopper plate 70 due to sink marks, voids, or the like. This allows the stopper plate 70 to be formed with high precision, thereby suppressing increases in the rotational resistance of the rotor 60. Furthermore, burrs generated during the molding of the stopper plate 70 can be released into the recessed portions 73a and recessed grooves 73b. Therefore, the recessed portions 73a and recessed grooves 73b also have the function of eliminating the need for deburring work, etc.

[0049] A large-diameter first annular protrusion 75 and a small-diameter second annular protrusion 76 are integrally provided on the other side surface 74 (the surface on the bearing mounting portion 61c side) of the large-diameter disk portion 71 in the axial direction of the rotating shaft 61. These first and second annular protrusions 75, 76 protrude from the other side surface 74 toward the magnet 63 and the rotor body 62 by the same protrusion height H (see FIG. 5). That is, the protrusion height of the first annular protrusion 75 from the other side surface 74 and the protrusion height of the second annular protrusion 76 from the other side surface 74 are the same. The first annular protrusion 75 is disposed radially outward from the large-diameter disk portion 71, and the second annular protrusion 76 is disposed radially inward from the large-diameter disk portion 71.

[0050] Here, the other side surface 74 faces the magnet 63 and the rotor body 62, and forms the facing portion in the present invention. Specifically, the first annular protrusion 75 is provided on the other side surface 74 at a portion facing the magnet 63, and supports the axial tip end of the magnet 63. Meanwhile, the second annular protrusion 76 is provided on the other side surface 74 at a portion facing the rotor body 62, and supports the axial tip end of the rotor body 62. As a result, the axial tip ends of the magnet 63 and the rotor body 62 are positioned by the stopper plate 70 so that they are flush with each other.

[0051] 7, an annular first adhesive accommodating recess 77 is provided between the first annular protrusion 75 and the second annular protrusion 76 in the radial direction of the stopper plate 70 to accommodate adhesive GL (see FIGS. 8 to 13) that has spilled out from between the rotor body 62 and the magnet 63. Specifically, the annular first adhesive accommodating recess 77 has a first recess 77a that is shallow in the axial direction of the stopper plate 70 and a second recess 77b that is deeper in the axial direction of the stopper plate 70 than the first recess 77a. Six of each of the first recess 77a and the second recess 77b are provided, and are arranged alternately in the circumferential direction of the stopper plate 70. As a result, even if a large amount of adhesive GL has spilled out from between the rotor body 62 and the magnet 63, the spilled adhesive GL can be sufficiently accommodated in the second recess 77b.

[0052] Furthermore, a second annular adhesive accommodating recess 78 is provided on the opposite side of the first annular protrusion 75 from the first adhesive accommodating recess 77 (radially outside the first annular protrusion 75) so as to sandwich the first annular protrusion 75 therebetween.

[0053] Here, a total of six communication passages 75a are provided in the first annular protrusion 75 so as to be aligned at equal intervals (60-degree intervals) in the circumferential direction (see the two-dot chain lines in FIG. 7). Specifically, these communication passages 75a are arranged at positions corresponding to the second recesses 77b in the radial direction of the stopper plate 70. The total of six communication passages 75a communicate between the first adhesive accommodating recess 77 and the second adhesive accommodating recess 78 in the radial direction of the stopper plate 70, that is, communicate between the radial inner side and the radial outer side of the first annular protrusion 75. This allows air AR2 and adhesive GL (see FIGS. 11 and 12) that are driven into the first adhesive accommodating recess 77 when the rotor body 62 is attached to the magnet 63 to pass through the communication passages 75a. In this way, by arranging the communicating passages 75a at equal intervals in the circumferential direction of the first annular protrusion 75, it is possible to evenly distribute the flow of air AR2 and the accompanying movement of adhesive GL in the circumferential direction of the stopper plate 70.

[0054] The second adhesive accommodating recess 78 corresponds to the adhesive accommodating portion of the present invention and is provided radially outward of the first annular protrusion 75. The second adhesive accommodating recess 78 is recessed radially inward from the outer periphery of the magnet 63 and accommodates the adhesive GL that has overflowed beyond the second recess 77b and out of the communicating passage 75a. Specifically, the depth DP1 (see FIG. 7) of the second adhesive accommodating recess 78 in the radial direction of the stopper plate 70 is large enough to accommodate the adhesive GL that has overflowed beyond the second recess 77b and passed through the communicating passage 75a. In other words, most of the adhesive GL that has overflowed between the rotor body 62 and the magnet 63 enters the inside of the first adhesive accommodating recess 77 and rarely reaches the second adhesive accommodating recess 78.

[0055] As a result, the adhesive GL that has spilled out from between the rotor body 62 and the magnet 63 does not bulge (spread out) radially outward from the stopper plate 70 and the magnet 63. Therefore, there is no need to perform work such as wiping off the spilled adhesive GL after assembling the rotor 60. In other words, the amount of adhesive GL used is set so that it sufficiently spreads between the rotor body 62 and the magnet 63 and does not spill out radially outward from the stopper plate 70 and the magnet 63.

[0056] The second annular protrusion 76 has a total of six communication grooves 76a arranged at equal intervals (60-degree intervals) around its circumference (see the two-dot chain lines in FIG. 7). These communication grooves 76a are located at positions corresponding to the second recesses 77b in the radial direction of the stopper plate 70, and communicate between the fitting hole 70a and the first adhesive accommodating recess 77, i.e., communicate between the radial inner and outer sides of the second annular protrusion 76. This allows air AR1 and AR3 (see FIGS. 10 and 11) to pass through the communication grooves 76a when the rotor body 62 is attached to the magnet 63. In other words, the communication grooves 76a facilitate the flow of air AR1 and AR3 when the rotor body 62 is attached to the magnet 63. This allows the adhesive GL to be distributed evenly between the rotor body 62 and the magnet 63.

[0057] [Rotor manufacturing method] Next, a method for manufacturing rotor 60 that forms brushless motor 10 formed as described above, i.e., an assembly procedure for rotor 60, will be described in detail with reference to the drawings. Prior to describing the assembly procedure for rotor 60, an assembly device used in the assembly work for rotor 60 will be described.

[0058] As shown by the dashed-dotted arrow in Figure 8, the rotor 60 is formed by assembling a rotating shaft sub-assembly SS, which is made up of a rotating shaft 61 and a rotor body 62, to a magnet sub-assembly MS, which is made up of a magnet 63 and a stopper plate 70. For this assembly work, an assembly device 100, shown in Figures 9 to 13, is used.

[0059] 9, the assembly device 100 includes first and second sliders 101 and 102 that hold the magnet sub-assembly MS, and a lifting member 103 that holds the rotating shaft sub-assembly SS. The first and second sliders 101 and 102 are immovable in the axial direction of the magnet sub-assembly MS, but are movable toward and away from each other in the radial direction of the magnet sub-assembly MS by a moving mechanism (hydraulic or electrically operated) not shown. The lifting member 103 is movable up and down in the axial direction of the rotating shaft sub-assembly SS by a lifting mechanism (hydraulic or electrically operated) not shown.

[0060] This allows the assembly device 100 to move (raise and lower) the movable position MP of the lifting member 103 relative to the fixed position FP of the first and second sliders 101 and 102, thereby assembling the rotating shaft sub-assembly SS to the magnet sub-assembly MS, or removing the completed rotor 60 (see Figure 13) from the first and second sliders 101 and 102.

[0061] Here, the lifting member 103 is arranged coaxially with the first and second sliders 101 and 102 which are linked to each other, and the first and second sliders 101 and 102 correspond to the first jig in the present invention, and the lifting member 103 corresponds to the second jig in the present invention.

[0062] [First jig setting process] First, the magnet 63 and the stopper plate 70 are prepared. Next, the axial tip of the magnet 63 (the lower part in FIG. 9) is brought into contact with the first annular protrusion 75 of the stopper plate 70, thereby forming the magnet sub-assembly MS.

[0063] 9, the first and second sliders 101 and 102 are moved closer to each other, sandwiching the magnet sub-assembly MS in the radial direction. As a result, the magnet sub-assembly MS is sandwiched between the first and second sliders 101 and 102, and the setting of the magnet sub-assembly MS to the first and second sliders 101 and 102 is completed.

[0064] This completes the "first jig setting step."

[0065] The magnet sub-assembly MS corresponds to the sub-assembly in this invention. Air grooves 101a and 102a are provided on the magnet sub-assembly MS side of the first and second sliders 101 and 102. These air grooves 101a and 102a face the butting portion between the magnet 63 and the stopper plate 70 in the radial direction of the magnet sub-assembly MS. As a result, air AR2 (see FIGS. 10 and 11) discharged from the butting portion between the magnet 63 and the stopper plate 70 flows into the respective air grooves 101a and 102a.

[0066] [Second jig setting process] Next, as shown in Figure 9, the axial base end of the rotating shaft 61 that forms the rotating shaft sub-assembly SS, i.e., the bearing mounting portion 61c, is attached to the lifting member 103. This sets the rotating shaft sub-assembly SS so that it hangs down from the lifting member 103. At this time, to make it easy to attach the rotating shaft sub-assembly SS to the lifting member 103, a sufficient distance D1 is set between the fixed position FP of the first and second sliders 101, 102 and the movable position MP of the lifting member 103.

[0067] This completes the "second jig setting step."

[0068] In Figures 8 to 13, the sensor bracket 65 and the sensor magnet SM (see Figure 5) are not attached to the rotating shaft sub-assembly SS, but these sensor bracket 65 and sensor magnet SM may be attached before assembling the rotor 60 or after assembling the rotor 60.

[0069] [Adhesive application process] Next, a predetermined amount of adhesive GL is applied to the inner wall 63a on the axial base end side (upper side in FIG. 9) of the magnet 63 that forms the magnet sub-assembly MS, so as to form a ring shape. Here, the amount of adhesive GL used is set so that it does not spill out radially outside the stopper plate 70 and magnet 63 after the rotor 60 is assembled.

[0070] A predetermined amount of adhesive GL is applied around the circumference of an outer wall 62a on the axial tip side (lower side in FIG. 9) of the rotor body 62 that forms the rotating shaft sub-assembly SS. The amount of adhesive GL used is set so that after the rotor 60 is assembled, the amount of adhesive GL slightly protrudes into the stepped portion DS (see FIG. 5) on the axial base end side of the rotor body 62 and magnet 63 (an amount that fits sufficiently into the annular space SP).

[0071] The application operation of the adhesive GL onto the inner wall 63a of the magnet 63 and the application operation of the adhesive GL onto the outer wall 62a of the rotor body 62 are each automatically and accurately performed by an adhesive application device (not shown).

[0072] [Insertion Step] Next, drive the elevating mechanism of the assembling device 100 to move the elevating member 103 so as to approach the first and second sliders 101 and 102. That is, as shown by the arrow M2 in FIG. 9, lower the elevating member 103 to bring it closer to the first and second sliders 101 and 102. Thereby, the distal end side in the axial direction (the lower side in FIG. 9) of the rotating shaft 61 forming the rotating shaft sub-assembly SS is made to face the proximal end side in the axial direction (the upper side in FIG. 9) of the magnet 63 forming the magnet sub-assembly MS.

[0073] Then, the distance D1 between the fixed position FP of the first and second sliders 101 and 102 and the movable position MP of the elevating member 103 gradually becomes shorter. Thereafter, as shown by the arrow M2 in FIG. 10, by continuously lowering the elevating member 103, the distal end side in the axial direction of the rotor body 62 is inserted into the proximal end side in the axial direction of the magnet 63.

[0074] At this time, the distance D2 between the fixed position FP of the first and second sliders 101 and 102 and the movable position MP of the elevating member 103 becomes shorter than the distance D1 (D2 < D1), and the adhesive GL applied to the inner wall 63a of the magnet 63 and the adhesive GL applied to the outer wall 62a of the rotor body 62 evenly spread between the inner wall 63a of the magnet 63 and the outer wall 62a of the rotor body 62 (see the thick dashed line).

[0075] Thereby, the [Insertion Step] is completed.

[0076] [Adhesive Bonding Step] Thereafter, as shown by the arrow M2 in Figures 10 and 11, when the axial tip side of the rotor body 62 is continuously inserted into the axial base end side of the magnet 63, the air AR inside the magnet 63 (see Figures 9 to 11) flows as air AR1 between the medium diameter portion 61b of the rotating shaft 61 and the fitting hole 70a of the stopper plate 70, as shown by the dashed arrow.

[0077] Furthermore, the air flows through the communication passage 75a (see FIG. 7) of the first annular protrusion 75 and the air grooves 101a and 102a of the first and second sliders 101 and 102 as air AR2.

[0078] Furthermore, the air flows through a plurality of clearances CR between the large diameter portion 61a of the rotary shaft 61 and the rotor body 62 as air AR3.

[0079] As a result, air AR (AR1, AR2, AR3) is discharged from inside the magnet 63 to the outside of the magnet sub-assembly MS.

[0080] As the air AR (AR1, AR2, AR3) is discharged to the outside, the adhesive GL spreads more evenly between the inner wall 63a of the magnet 63 and the outer wall 62a of the rotor body 62, as shown by the thick dashed line in Fig. 11. Thereafter, the large diameter portion 61a of the rotating shaft 61 is fitted into the fitting hole 70a of the stopper plate 70, as shown by the dashed circle in Fig. 11.

[0081] Then, the flow of air AR1 indicated by the dashed arrow is blocked, and air AR2 and AR3 indicated by the dashed arrow are generated. Here, the flow of air AR3 passes through the communicating groove 76a (see FIG. 7) of the second annular convex portion 76 and reaches the plurality of clearances CR, so the flow of air AR3 is smooth. Therefore, the flow of air AR2 and AR3 does not reduce the discharge performance of air AR. At this time, the distance D3 between the fixed position FP of the first and second sliders 101 and 102 and the movable position MP of the lifting member 103 is shorter than the distance D2 (D3 <D2)。

[0082] Furthermore, as shown by the arrow M2 in FIG. 12, when the insertion operation of the rotor body 62 into the magnet 63 is continuously advanced, the distance D4 between the fixed position FP of the first and second sliders 101 and 102 and the movable position MP of the elevating member 103 becomes even shorter than the distance D3 (D4 < D3). Then, the axial tip portion (the lower part in FIG. 12) of the rotor body 62 abuts against the second annular convex portion 76 of the stopper plate 70.

[0083] At this time, since the flow of the air AR1 (see FIG. 10) is blocked, the adhesive GL protruding from the axial tip side of the rotor body 62 and the magnet 63 reaches the first recess 77a and the second recess 77b (see FIG. 7) of the first adhesive accommodating recess 77 closer to the portion where the adhesive GL protrudes. Then, the protruding adhesive GL gently passes through the respective communication passages 75a (see FIG. 7) via the second recess 77b along with the flow of the air AR2 (see FIG. 11). Note that most of the protruding adhesive GL is accommodated in the second recess 77b. On the other hand, the communication groove 76a (see FIG. 7) is far from the portion where the adhesive GL protrudes with respect to the first recess 77a and the second recess 77b (see FIG. 7). Therefore, it is difficult for the protruding adhesive GL to reach the communication groove 76a.

[0084] Thereafter, although in a small amount, the adhesive GL that has exceeded the second recess 77b due to the flow of the air AR2 reaches the second adhesive accommodating recess 78 through the communication passage 75a. And the adhesive GL that has reached the second adhesive accommodating recess 78 does not protrude to the radially outer side of the stopper plate 70 and the magnet 63 because the adhesive GL has gently passed through the communication passage 75a and the depth dimension DP1 of the second adhesive accommodating recess 78 in the radial direction of the stopper plate 70 is sufficiently large.

[0085] Thereby, the assembly of the rotary shaft sub-assembly SS to the magnet sub-assembly MS is completed, that is, the adhesion between the rotor body 62 and the magnet 63 is completed, and the [adhesion process] ends.

[0086] [Removal process] Next, the assembled rotor 60 (without the magnet support member 64 attached) is removed from the assembling device 100. Specifically, the movement mechanism of the assembling device 100 is driven to move the first and second sliders 101, 102 away from each other, as shown by arrow M3 in FIG. 13. This makes it possible to remove the rotor 60 from the first and second sliders 101, 102.

[0087] Thereafter, the lifting mechanism of the assembling device 100 is driven to raise the lifting member 103 as shown by arrow M4 in Fig. 13, and move it away from the first and second sliders 101 and 102. Specifically, to make it easier to remove the rotor 60 from the lifting member 103, the distance D5 between the fixed position FP of the first and second sliders 101 and 102 and the movable position MP of the lifting member 103 is made longer than the distance D1 shown in Fig. 9 (D5>D1).

[0088] 13, the rotor 60, which is attached so as to hang down from the lifting member 103, is removed from the lifting member 103. As a result, the assembled rotor 60 (without the magnet support member 64 attached) is removed from the assembling apparatus 100, and the "removal process" is completed.

[0089] Here, before or after the [removal process], heat is applied to the assembled rotor 60 to harden the adhesive GL. During this process, the air AR accumulated in the first adhesive accommodating recess 77 expands, attempting to push the adhesive GL toward the second adhesive accommodating recess 78. However, the inner periphery of the rotor body 62 is provided with multiple clearances CR that connect to the communication grooves 76a (see FIG. 7). Therefore, when the adhesive GL hardens, the air AR accumulated in the first adhesive accommodating recess 77 becomes a flow of air AR3, which is smoothly discharged to the outside through the multiple clearances CR. Therefore, even when the adhesive GL hardens, the adhesive GL does not bulge (swell) radially outward from the stopper plate 70 and the magnet 63.

[0090] The magnet support member 64 (see FIG. 5) is then attached to the removed rotor 60, and the assembly of the rotor 60 is finally completed.

[0091] As described above in detail, according to embodiment 1, a first annular protrusion 75 that supports the axial tip of the magnet 63 is provided on the other side 74 of the stopper plate 70 at the portion facing the magnet 63, and a second annular protrusion 76 that supports the axial tip of the rotor body 62 is provided on the other side 74 of the stopper plate 70 at the portion facing the rotor body 62, and a communication passage 75a is provided in the first annular protrusion 75 that connects the radial inside and outside of the first annular protrusion 75.

[0092] As a result, when assembling the rotor 60, air AR2 flows gently through the communication passage 75a provided in the first annular protrusion 75 of the stopper plate 70. This prevents the adhesive GL that has spilled into the first adhesive accommodating recess 77 on the radially inner side of the first annular protrusion 75 from forcefully spilling into the second adhesive accommodating recess 78 on the radially outer side of the first annular protrusion 75. This makes it possible to improve the ease of assembly.

[0093] Furthermore, according to the first embodiment, a total of six communication passages 75a are provided at equal intervals (at 60-degree intervals) in the circumferential direction of the first annular protrusion 75, so that the flow of air AR2 and the accompanying movement of adhesive GL can be evenly dispersed in the circumferential direction of the stopper plate 70. This prevents the adhesive GL from concentrating and moving in one area, and makes it possible to eliminate the need for work such as wiping off excess adhesive GL after assembling the rotor 60, for example.

[0094] Furthermore, according to the first embodiment, a second adhesive containing recess 78 is provided radially outward from the first annular protrusion 75, which is recessed radially inward from the outer periphery of the magnet 63 and contains adhesive GL that has spilled out of the communicating passage 75a. This prevents the adhesive GL that has passed through the communicating passage 75a from spilling out radially outside the stopper plate 70 and the magnet 63. This also makes it possible to reliably eliminate the need for work such as wiping off the spilled adhesive GL after assembling the rotor 60.

[0095] Furthermore, according to the first embodiment, the protruding height of the first annular protrusion 75 from the other side surface 74 and the protruding height of the second annular protrusion 76 from the other side surface 74 are the same height H, so the adhesive GL that has spilled out from between the rotor body 62 and the magnet 63 is guided to the first adhesive containing recess 77. Therefore, the movement of the spilled adhesive GL can be easily controlled.

[0096] Furthermore, according to the first embodiment, the length L1 of the rotor body 62 in the axial direction of the rotating shaft 61 is longer than the length L2 of the magnet 63 in the axial direction of the rotating shaft 61 (L1>L2), so that a step portion DS can be formed on the axial base end side of the rotor body 62 and the magnet 63. Therefore, the adhesive GL that has spilled out from between the rotor body 62 and the magnet 63 can be contained in the annular space SP formed by the step portion DS.

[0097] Furthermore, according to the first embodiment, when assembling the rotor 60, the adhesive GL is applied to the inner wall 63a on the axial base end side of the magnet 63 and the outer wall 62a on the axial tip side of the rotor body 62, so that when the axial tip side of the rotor body 62 is inserted into the axial base end side of the magnet 63, the adhesive GL can be spread evenly between the inner wall 63a of the magnet 63 and the outer wall 62a of the rotor body 62. At that time, because the adhesive GL is applied in an annular shape to the inner wall 63a of the magnet 63 and the outer wall 62a of the rotor body 62, the adhesive GL can be applied evenly between the inner wall 63a of the magnet 63 and the outer wall 62a of the rotor body 62.

[0098] Furthermore, according to the first embodiment, work such as wiping off excess adhesive GL is not required, improving the ease of assembly of brushless motor 10, thereby enabling energy savings in the manufacture of brushless motor 10. This makes it possible to achieve the Sustainable Development Goals (SDGs) established by the United Nations, particularly Goal 7 (Ensure access to affordable, reliable, sustainable and modern energy for all) and Goal 13 (Take urgent action to combat climate change and its impacts).

[0099] [Embodiment 2] Next, a second embodiment of the present invention will be described in detail with reference to the drawings. Note that parts having the same functions as those in the first embodiment will be given the same reference numerals, and detailed description thereof will be omitted.

[0100] Figure 14 is a cross-sectional view showing the rotor alone of the brushless motor of embodiment 2, Figure 15 is an oblique view of the stopper plate alone of Figure 14 as seen from the sensor magnet side, Figure 16 is an oblique view of the stopper plate alone of Figure 14 as seen from the rotor core side, Figure 17 is an oblique view of the rotor of Figure 14 disassembled into two sub-assemblies, Figure 18 is a diagram corresponding to Figure 11 which explains the assembly procedure for the rotor of Figure 14, and Figure 19 is a diagram corresponding to Figure 12 which explains the assembly procedure for the rotor of Figure 14.

[0101] In the second embodiment, the structure of the rotor 80 is different from that of the first embodiment. Specifically, as shown in Fig. 14, in the rotor 80 of the second embodiment, the rotor body 62 is integrally provided on the outer periphery of the large diameter portion 61a of the rotary shaft 61. That is, in the rotor 80 of the second embodiment, a radially outer portion of the large diameter portion 61a serves as the rotor body 62.

[0102] Furthermore, in rotor 80 of embodiment 2, magnet 63 having a smaller diameter than magnet 63 of embodiment 1 (see FIG. 5) is fixed to the outer periphery of rotor body 62 via adhesive GL (see FIGS. 17 to 22). As a result, rotor 80 of embodiment 2 has a smaller diameter than rotor 60 of embodiment 1 (see FIG. 5). Therefore, brushless motor 80 of embodiment 2 (not shown) is smaller in size than brushless motor 10 of embodiment 1 (see FIG. 4).

[0103] 14, in the rotor 80 of the second embodiment, the length L1 of the rotor body 62 is also longer than the length L2 of the magnet 63 (L1>L2). Therefore, a step portion DS is formed on the axial base end side of the rotor body 62 and the magnet 63, and the step portion DS functions as an annular space SP.

[0104] Furthermore, in rotor 80 of embodiment 2, pinion gear portion 61d (see FIG. 5) on the axial tip side of medium diameter portion 61b is omitted compared to rotor 60 of embodiment 1. Instead, a separate pinion gear (not shown) is fixed to the axial tip side of rotating shaft 61 (left side in FIG. 14).

[0105] Furthermore, in rotor 80 of embodiment 2, compared to rotor 60 of embodiment 1, magnet support member 64 (see FIG. 5) that covers the outer periphery of magnet 63 is omitted. This reduces the inertial mass of rotor 80, suppressing an increase in the rotational resistance of rotor 80.

[0106] Furthermore, rotor 80 of embodiment 2 differs from rotor 60 of embodiment 1 in the shape of stopper plate 70. Specifically, as shown in Fig. 15, thick-walled cylindrical portion 73 provided on one side surface 72 of large-diameter disk portion 71 does not have a recessed portion 73a (see Fig. 6). This is because stopper plate 70 of embodiment 2 has a smaller diameter than stopper plate 70 of embodiment 1, and there is no concern about sink marks, voids, and the like occurring.

[0107] 16, in the stopper plate 70 of the second embodiment, a single annular protrusion 81 having a protruding height H is provided on the other side surface 74 of the large diameter circular plate portion 71. Here, the annular protrusion 81 is made up of a first annular protrusion 75 and a second annular protrusion 76, and is formed by integrating these first annular protrusion 75 and second annular protrusion 76 with each other. In FIG. 16, the boundary between the first annular protrusion 75 and the second annular protrusion 76 is indicated by a dashed line.

[0108] Here, in the stopper plate 70 of embodiment 2, by integrating the first annular convex portion 75 and the second annular convex portion 76, the first adhesive accommodating recess 77 (see Figure 7) of embodiment 1 is not provided, and only the second adhesive accommodating recess 78 is provided radially outside the annular convex portion 81 (radially outside the first annular convex portion 75).

[0109] A total of six communication passages 75a are arranged in the annular protrusion 81, which is made up of the first annular protrusion 75 and the second annular protrusion 76, at equal intervals (60-degree intervals) in the circumferential direction (see the two-dot chain lines in FIG. 16). In other words, these communication passages 75a are provided in both the first annular protrusion 75 and the second annular protrusion 76, and connect the radially inner side and the radially outer side of the annular protrusion 81.

[0110] Here, air AR2 and adhesive GL pass through each of the communication paths 75a when the rotor body 62 is attached to the magnet 63 (see FIGS. 20 and 21). In addition, in the stopper plate 70 of embodiment 2, the depth dimension DP2 (see FIG. 16) of the second adhesive receiving recess 78 in the radial direction of the stopper plate 70 is greater than the depth dimension DP1 (see FIG. 7) of the second adhesive receiving recess 78 in the stopper plate 70 of embodiment 1 (DP2>DP1). Therefore, the adhesive GL that has passed through the communication paths 75a can be more sufficiently accommodated.

[0111] [Rotor manufacturing method] In the manufacturing method of the rotor 80, the flow path of the air AR2 in the latter stage of the "bonding step" is slightly different from that in the first embodiment. Specifically, as shown in Fig. 18, after the flow of the air AR1 indicated by the dashed arrow is blocked, only the flow of the air AR2 indicated by the dashed arrow remains. The air AR2 then flows into the second adhesive containing recess 78 via the respective communication paths 75a (see Fig. 16) provided in the annular protrusion 81.

[0112] 19, as the insertion of the rotor body 62 into the magnet 63 continues, the axial tip end (lower part in FIG. 19) of the rotor body 62 abuts against the second annular protrusion 76 that forms the annular protrusion 81. At this time, the adhesive GL that has spilled out onto the axial tip sides of the rotor body 62 and the magnet 63 flows gently through the respective communication passages 75a (see FIG. 16) along with the flow of air AR2.

[0113] Thereafter, the adhesive GL that has passed through each of the communication paths 75a reaches the second adhesive accommodating recess 78. Then, the adhesive GL that has reached the second adhesive accommodating recess 78 does not spill out radially outside the stopper plate 70 and magnet 63 because it has passed through the communication paths 75a slowly and because the depth dimension DP2 of the second adhesive accommodating recess 78 in the radial direction of the stopper plate 70 is sufficiently large.

[0114] The second embodiment configured as described above can also achieve the same effects as the first embodiment. In addition, in the second embodiment, the first annular protrusion 75 and the second annular protrusion 76 are integrated with each other as the annular protrusion 81, which reduces the radial dimension of the stopper plate 70. This allows the rotor 80 to have a smaller diameter, thereby achieving a further miniaturization of the brushless motor. Furthermore, the magnet support member 64 (see FIG. 5) that covers the outer periphery of the magnet 63 is omitted, which reduces the inertial mass of the rotor 80 and prevents an increase in the rotational resistance of the rotor 80. This makes it possible to drive the brushless motor with less power.

[0115] The present invention is not limited to the above-described embodiments and can be modified in various ways without departing from the spirit and scope of the present invention. For example, in the above-described embodiments, a total of six communication passages 75a are provided, but the present invention is not limited to this. A total of two communication passages or a total of seven or more communication passages can be provided depending on the state of the adhesive GL that has spilled out from between the rotor body 62 and the magnet 63. Furthermore, the communication passages 75a may be arranged at uneven intervals around the circumferential direction of the stopper plate 70 rather than at equal intervals.

[0116] In addition, in the above-described embodiment, the protruding heights of the first annular convex portion 75 and the second annular convex portion 76 are set to the same height H, but the present invention is not limited to this, and the protruding heights of the first annular convex portion 75 and the second annular convex portion 76 can also be made different from each other in order to control how the adhesive GL overflows from between the rotor body 62 and the magnet 63.

[0117] Furthermore, in the above-described embodiment, the assembly device 100 is shown in which the first and second sliders 101, 102 are fixed in the axial direction of the rotors 60, 80 and the lifting member 103 is movable in the axial direction of the rotors 60, 80, but the present invention is not limited to this. For example, the assembly device 100 may be configured so that the lifting member 103 is fixed in the axial direction of the rotors 60, 80 and the first and second sliders 101, 102 are movable in the axial direction of the rotors 60, 80, or both the first and second sliders 101, 102 and the lifting member 103 are movable relative to each other in the axial direction of the rotors 60, 80.

[0118] Furthermore, the material, shape, dimensions, number, installation location, etc. of each component in each of the above-described embodiments are arbitrary as long as they can achieve the present invention, and are not limited to each of the above-described embodiments. [Explanation of symbols]

[0119] 10: brushless motor, 11: driven object, 20: case, 21: cylindrical portion, 22: bottom wall portion, 23: opening, 24: flange portion, 25: stator, 26: stator core, 26a: core body, 26b: teeth, 27: insulator, 28: coil, 29: busbar unit, 30: conductive member, 40: bracket, 41: partition wall portion, 42: insertion tube portion, 43: bearing holder, 44: annular fixing plate, 45: cylindrical wall portion, 45a: case facing surface, 45b: driven object facing surface, 45c: annular recess, 46: driven object fixing portion, 47: Case fixing portion, 48: Cap nut, 49: Fitting cylindrical portion, 50: Sensor board, 51: Hall element, 60: Rotor, 61: Rotating shaft, 61a: Large diameter portion, 61b: Medium diameter portion, 61c: Bearing mounting portion, 61d: Pinion gear portion, 62: Rotor body, 62a: Outer wall, 63: Magnet, 63a: Inner wall, 64: Magnet support member, 64a: Bottom wall, 64b: Covering wall, 64c: Crimping portion, 65: Sensor bracket, 70: Stopper plate (positioning member), 70a: Fitting hole, 71: Large diameter disc portion, 72: One side surface, 73: Thick cylindrical portion, 73a : Recessed portion, 73b: Groove, 74: Other side surface (opposing portion), 75: First annular convex portion, 75a: Communication passage, 76: Second annular convex portion, 76a: Communication groove, 77: First adhesive accommodating recess, 77a: First recess, 77b: Second recess, 78: Second adhesive accommodating recess (adhesive accommodating portion), 80: Rotor, 81: Annular convex portion (single convex portion), 100: Assembly device, 101: First slider (first jig), 102: Second slider (second jig), 101a, 102a: Air groove, 103: Elevating member (second jig), AG: Air gap, AR, AR1, AR2: Air, BB1: First ball bearing, BB2: Second ball bearing, CL: Collar, CN1: Power connector connection, CN2: Sensor connector connection, CP: Convex mating portion, CR: Clearance, DS: Step, FP: Fixed position, G: Depression, GL: Adhesive, MP: Movable position, MS: Magnet sub-assembly (sub-assembly), S1: First screw member, S2: Second screw member, SC: Fixing screw, SL1: First annular seal, SL2: Second annular seal, SM: Sensor magnet, SP: Annular space, SS: Rotating shaft sub-assembly

Claims

1. A brushless motor having a rotor that rotates relative to a stator, The rotor is A rotor body; a rotating shaft rotated by the rotor body; a magnet fixed to the outer periphery of the rotor body with an adhesive; a positioning member attached to the rotary shaft for positioning the magnet and the rotor body in the axial direction of the rotary shaft; and a first annular protrusion that supports an axial tip of the magnet is provided on a portion of the positioning member that faces the magnet, a second annular protrusion that supports an axial tip of the rotor body is provided on a portion of the positioning member that faces the rotor body; The first annular protrusion is provided with a communication passage that connects the radially inner side and the radially outer side of the first annular protrusion. Brushless motor.

2. The plurality of communication passages are provided at equal intervals in the circumferential direction of the first annular protrusion.

2. The brushless motor according to claim 1.

3. 3. The brushless motor according to claim 1, an adhesive containing portion that is recessed radially inward from an outer periphery of the magnet and that contains the adhesive that has overflowed from the communication passage is provided radially outward from the first annular protrusion; Brushless motor.

4. a protruding height of the first annular convex portion from the opposing portion and a protruding height of the second annular convex portion from the opposing portion are the same height.

2. The brushless motor according to claim 1.

5. The length of the rotor body in the axial direction of the rotary shaft is longer than the length of the magnet in the axial direction of the rotary shaft.

5. The brushless motor according to claim 4.

6. the first annular protrusion and the second annular protrusion are integrated with each other; 2. The brushless motor according to claim 1.

7. A rotor body; a rotating shaft rotated by the rotor body; a magnet adhesively fixed to the outer periphery of the rotor body; a positioning member attached to the rotary shaft for positioning the magnet and the rotor body in the axial direction of the rotary shaft; A method for manufacturing a rotor having a first annular protrusion that supports an axial tip of the magnet is provided on a portion of the positioning member that faces the magnet, a second annular protrusion that supports an axial tip of the rotor body is provided on a portion of the positioning member that faces the rotor body; a communication passage that communicates between a radially inner side and a radially outer side of the first annular protrusion is provided in the first annular protrusion, a first jig setting step of forming a sub-assembly by abutting an axial tip end portion of the magnet against the first annular convex portion and setting the sub-assembly in a first jig; a second jig setting step of setting an axial base end portion of the rotating shaft in a second jig provided coaxially with the first jig; an adhesive application step of applying an adhesive to the magnet and the rotor body; an insertion process of moving at least one of the first jig and the second jig, bringing the axial tip side of the rotating shaft into contact with the axial base end side of the magnet, and inserting the axial tip side of the rotor body into the axial base end side of the magnet; a bonding process in which the adhesive is spread between the rotor body and the magnet while discharging air inside the magnet to the outside of the magnet through the communication passage, and the axial tip end of the rotor body is abutted against the second annular convex portion; Equipped with A method for manufacturing a rotor.

8. In the adhesive application step, the adhesive is applied to an inner wall of the magnet on the axial base end side and an outer wall of the rotor body on the axial tip end side. The method for manufacturing the rotor according to claim 7 .

9. In the adhesive application step, the adhesive is applied in an annular shape to the inner wall of the magnet and the outer wall of the rotor body. The method for manufacturing a rotor according to claim 8 .

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