Method for manufacturing brushless motors and rotors

Abstract

A method for manufacturing a brushless motor and a rotor that can improve assembly workability is provided. [Solution] 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, 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, facing the rotor body 62, and a communication passage 75a that connects the radial inside and radial outside of the first annular protrusion 75 is provided in the first annular protrusion 75. When assembling the rotor 60, air flows gently through the communication passage 75a, so that adhesive that has spilled into a first adhesive-receiving recess 77 on the radial inside of the first annular protrusion 75 does not forcefully spill into a second adhesive-receiving recess 78 on the radial outside of the first annular protrusion 75. This improves assembly workability.

Description

Technical Field

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

Background Art

[0002] Conventionally, some brushless motors include a stator fixed to a case and a rotor that rotates with respect to the stator. Such a brushless motor is a so-called inner rotor type brushless motor and is used as a drive source for an electric brake device, a power steering device, etc. mounted on a vehicle such as an automobile.

[0003] For example, Patent Document 1 describes a brushless motor applicable as a drive source for an electric brake device. The rotor forming the brushless motor described in Patent Document 1 has a rotor core, a shaft fixed to the rotor core, a magnet cover mounted on the shaft and abutted against the rotor core, and a ring magnet mounted on the rotor core and abutted against the magnet cover.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the technique described in Patent Document 1, an annular outer rib is provided on the radially outer side of the main body portion forming the magnet cover, and the end portion of the ring magnet is supported on the entire axial end surface of this outer rib.

[0006] As a result, when assembling the rotor, if a ring magnet is attached to the rotor core and the end of the ring magnet is pressed against the entire axial end of the outer rib, the air inside the outer rib in the radial direction is forcefully expelled to the radially outward side of the outer rib at that moment. Consequently, any adhesive that has squeezed out into the adhesive pocket is ejected radially outward from the outer rib, creating a problem where the adhesive needs to be wiped away.

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

[0008] The brushless motor of the present invention is a brushless motor comprising a rotor that rotates relative to a stator, wherein the rotor comprises a rotor body, a rotating shaft rotated by the rotor body, a magnet fixed to the outer circumference of the rotor body with adhesive, and a positioning member mounted on the rotating shaft for positioning the magnet and the rotor body in the axial direction of the rotating shaft, wherein the positioning member has a first annular projection on the part facing the magnet that supports the axial tip of the magnet, and the positioning member has a second annular projection on the part facing the rotor body that supports the axial tip of the rotor body, and the first annular projection is provided with a communication passage that connects the radially inner and radially outer sides of the first annular projection.

[0009] The present invention provides a method for manufacturing a rotor comprising: a rotor body; a rotating shaft rotated by the rotor body; a magnet adhesively fixed to the outer circumference of the rotor body; and a positioning member mounted on the rotating shaft for positioning the magnet and the rotor body in the axial direction of the rotating shaft, wherein the positioning member has a first annular projection on the part facing the magnet that supports the axial tip of the magnet, and a second annular projection on the part facing the rotor body that supports the axial tip of the rotor body, and the first annular projection has a communication passage connecting the radially inner and radially outer sides of the first annular projection, and the axial tip of the magnet abuts against the first annular projection to form a subassembly. The method comprises: a first jig setting step of setting the sub-assembly into a first jig; a second jig setting step of setting the axial base end of the rotating shaft into a second jig provided coaxially with respect to the first jig; an adhesive application step of applying adhesive to the magnet and the rotor body; an insertion step of moving at least one of the first jig and the second jig so that the axial tip end 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 an bonding step of discharging the air inside the magnet to the outside of the magnet through the communication passage, spreading the adhesive between the rotor body and the magnet, and bringing the axial tip end of the rotor body into contact with the second annular projection. [Effects of the Invention]

[0010] According to the present invention, during rotor assembly, air flows gently through the communication passage provided in the first annular protrusion of the positioning member. Therefore, adhesive that has squeezed out radially inward from the first annular protrusion is prevented from forcefully squeezing out radially outward from the first annular protrusion. Thus, it is possible to improve assembly workability. [Brief explanation of the drawing]

[0011] [Figure 1] This is a perspective view showing an example of the use of the brushless motor according to Embodiment 1. [Figure 2] It is a perspective view of the brushless motor of FIG. 1 as viewed from the bracket side. [Figure 3] It is a perspective view of the brushless motor of FIG. 1 as viewed from the case side. [Figure 4] It is a cross-sectional view showing the internal structure of the brushless motor of FIG. 1. [Figure 5] It is a cross-sectional view showing the rotor alone of FIG. 4. [Figure 6] It is a perspective view of the stopper plate alone of FIG. 5 as viewed from the sensor magnet side. [Figure 7] It is a perspective view of the stopper plate alone of FIG. 5 as viewed from the rotor core side. [Figure 8] It is a perspective view of the rotor of FIG. 5 disassembled into two sub-assemblies. [Figure 9] It is a diagram for explaining the first rotor assembly procedure of FIG. 5. [Figure 10] It is a diagram for explaining the second rotor assembly procedure of FIG. 5. [Figure 11] It is a diagram for explaining the third rotor assembly procedure of FIG. 5. [Figure 12] It is a diagram for explaining the fourth rotor assembly procedure of FIG. 5. [Figure 13] It is a diagram for explaining the fifth rotor assembly procedure of FIG. 5. [Figure 14] It is a cross-sectional view showing the rotor alone of the brushless motor of Embodiment 2. [Figure 15] It is a perspective view of the stopper plate alone of FIG. 14 as viewed from the sensor magnet side. [Figure 16] It is a perspective view of the stopper plate alone of FIG. 14 as viewed from the rotor core side. [Figure 17] It is a perspective view of the rotor of FIG. 14 disassembled into two sub-assemblies. [Figure 18] It is a diagram corresponding to FIG. 11 for explaining the rotor assembly procedure of FIG. 14. [Figure 19] It is a diagram corresponding to FIG. 12 for explaining the rotor assembly procedure of FIG. 14.

Best Mode for Carrying Out the Invention

[0012] [Embodiment 1] Hereinafter, Embodiment 1 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 according to Embodiment 1, FIG. 2 is a perspective view of the brushless motor of FIG. 1 as viewed from the bracket side, FIG. 3 is a perspective view of the brushless motor of FIG. 1 as viewed 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 showing the rotor alone of FIG. 4, FIG. 6 is a perspective view of the stopper plate alone of FIG. 5 as viewed from the sensor magnet side, and FIG. 7 is a perspective view of the stopper plate alone of FIG. 5 as viewed from the rotor core side.

[0014] Also, FIG. 8 is a perspective view of the rotor of FIG. 5 disassembled into two sub-assemblies, FIG. 9 is a diagram for explaining the assembly procedure 1 of the rotor of FIG. 5, FIG. 10 is a diagram for explaining the assembly procedure 2 of the rotor of FIG. 5, FIG. 11 is a diagram for explaining the assembly procedure 3 of the rotor of FIG. 5, FIG. 12 is a diagram for explaining the assembly procedure 4 of the rotor of FIG. 5, and FIG. 13 is a diagram for explaining the assembly procedure 5 of the rotor of FIG. 5.

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

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

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

[0018] [Stata] As shown in Figure 4, a stator 25 is housed inside the case 20. Specifically, the stator 25 is fixed to the radially inward side of the cylindrical portion 21 by press-fitting or the like. The stator 25 includes a stator core 26 formed in a substantially 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 substantially cylindrical shape and a plurality of teeth 26b that protrude radially inward from the core body 26a.

[0019] Each of the multiple teeth 26b is fitted with a resin insulator 27, and on the outside of the insulator 27, a coil 28 consisting of U-phase, V-phase, and W-phase is wound in a predetermined winding pattern and number of turns. In other words, each of the multiple teeth 26b has a three-phase coil 28 wound around it via an insulator 27 that functions as an insulator. The three-phase coils 28 are arranged alternately in the circumferential direction of the stator 25 in the order of U-phase, V-phase, W-phase, U-phase, V-phase, W-phase...

[0020] Furthermore, an annular busbar unit 29 is mounted on the axial end side of the stator 25 (upper side in Figure 4). The busbar unit 29 has a total of three conductive members 30 corresponding to the U phase, V phase, and W phase, and the ends of the three-phase coils 28 are electrically connected to one end of each of these conductive members 30.

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

[0022] [bracket] Here, the bracket 40 has the function of fixing the brushless motor 10 to the object to be driven 11 (see Figure 1). The bracket 40 is an injection-molded product made by injection molding a resin material such as molten plastic, and as shown in Figure 4, it closes the opening 23 of the case 20.

[0023] The bracket 40 is equipped with a partition wall portion 41 that is formed in a substantially disc shape. The partition wall portion 41 has the function of separating the case 20 side (lower side in Figure 4) from the drive object 11 side (upper side in Figure 4), and an insertion cylinder portion 42 is integrally provided in the center of the partition wall portion 41 through which the axial end side (upper side in Figure 4) of the rotating shaft 61 is inserted.

[0024] Furthermore, a bearing holder 43, formed in a roughly cup shape by press-forming a steel plate, is provided on the radially inner side of the insertion cylinder portion 42. Specifically, the radially outer side of the bearing holder 43 is fixed to the radially inner side of the insertion cylinder portion 42. The bearing holder 43 holds a first ball bearing BB1 that rotatably supports the axial end of the rotating shaft 61. An annular fixing plate 44 is provided on the axial base end side (lower side in Figure 4) of the first ball bearing BB1 to prevent it from falling out of the bearing holder 43.

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

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

[0027] As shown in Figure 4, a cylindrical wall portion 45 forming the outer casing of the bracket 40 is provided on the radially outer side of the insertion cylinder portion 42. The cylindrical wall portion 45 is thicker than the insertion cylinder portion 42 and is integrally provided on the radially outer side of the partition wall portion 41. The cylindrical wall portion 45 is also arranged coaxially with respect to the insertion cylinder portion 42 and extends in the axial direction of the rotation shaft 61. On the axial base end side of the cylindrical wall portion 45 (lower side in Figure 4), a case-facing surface 45a is provided, which faces the flange portion 24 of the case 20. On the other hand, on the axial tip side of the cylindrical wall portion 45 (upper side in Figure 4), a drive-object-facing surface 45b is provided, which faces the drive-object 11.

[0028] The cylindrical wall portion 45 is integrally provided with a total of three drive target fixing portions 46. Metal collars CL are attached to these drive target fixing portions 46. Therefore, the brushless motor 10 can be firmly fixed to the drive target 11 without damaging the resin drive target fixing portions 46. A second screw member S2 for fixing the brushless motor 10 to the drive target 11 is inserted through the collar CL.

[0029] Furthermore, a power connector connection section CN1 and a sensor connector connection section CN2 are integrally provided on the radially outer side of the cylindrical wall section 45. The power connector connection section CN1 and the sensor connector connection section CN2 are each formed in the shape of a roughly rectangular box. The vehicle's power connector and sensor connector are then inserted into the power connector connection section CN1 and the sensor connector connection section CN2 from one longitudinal side (upper left side in Figure 2), respectively.

[0030] Furthermore, the cylindrical wall portion 45 is integrally provided with a total of three case fixing portions 47. These case fixing portions 47 are the parts 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. The first threaded member S1, which fixes the case 20 to the bracket 40, is screwed to each of these cap nuts 48.

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

[0032] Furthermore, a fitting cylinder portion 49 is integrally provided on the axial base end side of the bracket 40. The fitting cylinder portion 49 is the part that fits 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 its radially outer side. The first annular seal SL1 seals the space between the bracket 40 and the case 20.

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

[0034] [Rotor] As shown in Figures 4, 5, and 8, the brushless motor 10 includes a rotor 60 that rotates relative to the stator 25. The 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. The rotating shaft 61 has a large diameter section 61a and a medium diameter section 61b. A rotor body 62, which is formed into a roughly cylindrical shape by laminating multiple thin steel plates, is fixed to the outer circumference of the large diameter section 61a. Specifically, the inner circumference of the rotor body 62 is provided with multiple fitting protrusions CP that extend in the axial direction of the rotor body 62 and are arranged at equal intervals in the circumferential direction (see Figure 8). These fitting protrusions CP are press-fitted onto the outer circumference of the large diameter section 61a. As a result, the two are firmly fixed to each other, and the rotating shaft 61 is rotated by the rotation of the rotor body 62. There is a clearance CR between the rotor body 62 and the large diameter section 61a where no fitting protrusions CP are provided (see Figure 5). Furthermore, the axial base end side of the large-diameter portion 61a (right side in Figure 5) and the axial base end side of the rotor body 62 (right side in Figure 5) are aligned in the axial direction so that they are flush with each other.

[0036] Furthermore, a bearing mounting portion 61c is provided at the axial base end 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. Thus, the rotating shaft 61 is rotatably supported by a total of two 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 bonded and fixed to the outer circumference of the rotor body 62 using adhesive GL (see Figures 8 to 13). In other words, the brushless motor 10 is a surface-permanent magnet type brushless motor in which the magnet 63 is attached to the surface of the rotor body 62. The axial position of the axial end of the rotor body 62 (left side in Figure 5) and the axial end of the magnet 63 (left side in Figure 5) are aligned so that they are flush with each other.

[0038] Furthermore, the outer circumference of the magnet 63 is covered by a cylindrical magnet support member 64 made of stainless steel or the like. The magnet support member 64 comprises a disc-shaped bottom wall 64a that abuts against the axial base end of the rotor body 62, and a cylindrical covering wall 64b integrally provided on the outer edge of the bottom wall 64a and extending 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 (left side in Figure 5) of the covering wall 64b.

[0039] The crimped portion 64c 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. A resin stopper plate 70 is provided between the axial end of the magnet 63 and the crimped portion 64c to prevent the crimping force used to form the crimped portion 64c from being applied to the magnet 63.

[0040] In this way, by providing the magnet support member 64, the air gap AG (tiny gap) between the rotor body 62 and the stator 25 is maintained 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 ends of the rotor body 62 and the magnet 63 so that they are flush with the axial direction of the rotation 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 stepped 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 stepped portion DS and the magnet support member 64. The annular space SP can accommodate the adhesive GL (see Figures 8 to 13) that protrudes from between the rotor body 62 and the magnet 63. Therefore, the protruding adhesive GL does not bulge radially outward of the magnet support member 64, and the air gap AG is reliably secured.

[0042] Furthermore, an annular sensor magnet SM is attached to the outer circumference of the middle diameter portion 61b via a sensor bracket 65. Specifically, the sensor magnet SM is positioned approximately in the center in the axial direction of the rotating shaft 61. The sensor magnet SM is used to detect the rotational state of the rotating shaft 61 and rotates in accordance with the rotation of the rotating shaft 61. The sensor magnet SM has alternating north and south poles in the circumferential direction, and a Hall element 51 facing the sensor magnet SM detects changes in the magnetic poles of the sensor magnet SM. As a result, the on-board controller (not shown) grasps the rotational state of the rotating shaft 61 (rotational direction, rotational speed, etc.) and optimally controls the rotation of the rotor 60 based on this.

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

[0044] [Stopper plate] As shown in Figures 5 to 7, the stopper plate 70 is formed in a roughly disc shape by injection molding of 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 the portion of the large diameter portion 61a closer to the medium diameter portion 61b is fitted into this fitting hole 70a. In other words, the stopper plate 70 is mounted coaxially with respect to the rotation axis 61.

[0045] Here, the stopper plate 70 has the function of preventing the crimping force from being transmitted to the magnet 63 when crimping the crimping portion 64c, and the positioning function of positioning the axial end faces 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 rotation shaft 61, and corresponds to the positioning member in the present invention.

[0046] The stopper plate 70 is equipped with a large-diameter disc portion 71. In the axial direction of the rotating shaft 61, a thick-walled cylindrical portion 73 is integrally provided on one side surface 72 of the large-diameter disc portion 71 (the side facing the pinion gear portion 61d). The axial thickness of the thick-walled cylindrical portion 73 is greater than the axial thickness of the large-diameter disc portion 71, specifically, it is about four times thicker. In contrast, the outer diameter of the thick-walled cylindrical portion 73 is smaller than the outer diameter of the large-diameter disc portion 71. As a result, a recess G is formed on the outer circumference of one side surface 72 of the large-diameter disc portion 71, and the crimping portion 64c fits into this recess G.

[0047] The thick-walled cylindrical portion 73 is provided with a total of six material-removing sections 73a. Additionally, the thick-walled cylindrical portion 73 is provided with a total of six grooves 73b. The grooves 73b are located between adjacent material-removing sections 73a in the circumferential direction of the thick-walled cylindrical portion 73, and are recessed in the same direction as the material-removing sections 73a in the axial direction of the thick-walled cylindrical portion 73. The depth of the grooves 73b is shallower than the depth of the material-removing sections 73a.

[0048] These material-removing sections 73a and grooves 73b are arranged at equal intervals (60-degree intervals) in the circumferential direction of the thick-walled cylindrical section 73. By providing these material-removing sections 73a and grooves 73b, the volume of the thick-walled cylindrical section 73 is reduced, thereby lightening the stopper plate 70 and preventing the stopper plate 70 from being distorted by sink marks or voids. As a result, the stopper plate 70 can be formed with high precision, and consequently, the increase in rotational resistance of the rotor 60 is suppressed. Furthermore, burrs generated during the molding of the stopper plate 70 can be redirected to the material-removing sections 73a and grooves 73b. Therefore, the material-removing sections 73a and grooves 73b also have the function of eliminating the need for deburring work.

[0049] In the axial direction of the rotating shaft 61, a large-diameter first annular projection 75 and a small-diameter second annular projection 76 are integrally provided on the other side 74 (the side facing the bearing mounting portion 61c) of the large-diameter disc portion 71. These first and second annular projections 75 and 76 protrude from the other side 74 toward the magnet 63 and rotor body 62, respectively, with the same projection height H (see Figure 5). That is, the projection height of the first annular projection 75 from the other side 74 and the projection height of the second annular projection 76 from the other side 74 are the same. The first annular projection 75 is positioned radially outward of the large-diameter disc portion 71, and the second annular projection 76 is positioned radially inward of the large-diameter disc portion 71.

[0050] Here, the other side 74 faces the magnet 63 and the rotor body 62, forming the opposing portion in the present invention. Specifically, the first annular projection 75 is provided on the portion of the other side 74 facing the magnet 63 and supports the axial end of the magnet 63. On the other hand, the second annular projection 76 is provided on the portion of the other side 74 facing the rotor body 62 and supports the axial end of the rotor body 62. As a result, the axial end sides of the magnet 63 and the rotor body 62 are positioned flush with each other by the stopper plate 70.

[0051] Furthermore, as shown in Figure 7, in the radial direction of the stopper plate 70, an annular first adhesive-retaining recess 77 is provided between the first annular protrusion 75 and the second annular protrusion 76 to accommodate the adhesive GL (see Figures 8 to 13) that has squeezed out from between the rotor body 62 and the magnet 63. Specifically, the annular first adhesive-retaining recess 77 has a first recess 77a with a shallow depth dimension in the axial direction of the stopper plate 70, and a second recess 77b with a depth dimension in the axial direction of the stopper plate 70 that is deeper than the first recess 77a. Six of these first recesses 77a and second recesses 77b are provided and arranged alternately in the circumferential direction of the stopper plate 70. As a result, even when there is a large amount of adhesive GL squeezed out from between the rotor body 62 and the magnet 63, the squeezed adhesive GL can be sufficiently contained in the second recess 77b.

[0052] Furthermore, an annular second adhesive-retaining recess 78 is provided on the side opposite to the first adhesive-retaining recess 77 (radially outward from the first annular protrusion 75), sandwiching the first annular protrusion 75.

[0053] Here, the first annular protrusion 75 is provided with a total of six connecting passages 75a arranged at equal intervals (60-degree intervals) in its circumferential direction (see the dashed line in Figure 7). Specifically, these connecting passages 75a are located in the radial direction of the stopper plate 70, corresponding to the second recess 77b. The total of six connecting passages 75a connect the first adhesive-retaining recess 77 and the second adhesive-retaining recess 78 in the radial direction of the stopper plate 70, that is, they connect the radially inner and radially outer sides of the first annular protrusion 75. As a result, when the rotor body 62 is attached to the magnet 63, air AR2 and adhesive GL (see Figures 11 and 12) that are pushed into the first adhesive-retaining recess 77 can pass through the connecting passages 75a. In this way, by arranging the connecting 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-retaining recess 78 corresponds to the adhesive-retaining portion in this invention and is provided on the radially outer side of the first annular protrusion 75. The second adhesive-retaining recess 78 is recessed radially inward from the outer circumference of the magnet 63 and accommodates the adhesive GL that has overflowed the second recess 77b and protruded from the communication passage 75a. Specifically, the depth dimension DP1 (see Figure 7) of the second adhesive-retaining recess 78 in the radial direction of the stopper plate 70 is sufficient to accommodate the adhesive GL that has overflowed the second recess 77b and passed through the communication passage 75a. In other words, most of the adhesive GL that protrudes between the rotor body 62 and the magnet 63 enters the first adhesive-retaining recess 77 and hardly reaches the second adhesive-retaining recess 78.

[0055] As a result, any adhesive GL that squeezes out from between the rotor body 62 and the magnet 63 does not bulge (squeeze out) radially outward from the stopper plate 70 and the magnet 63. Therefore, after assembling the rotor 60, it is unnecessary to wipe off any excess adhesive GL. In other words, the amount of adhesive GL used is set to be sufficient to spread between the rotor body 62 and the magnet 63, without squeezing out radially outward from the stopper plate 70 and the magnet 63.

[0056] Furthermore, the second annular projection 76 is provided with a total of six communication grooves 76a arranged at equal intervals (60-degree intervals) in the circumferential direction (see the dashed line in Figure 7). These communication grooves 76a are positioned in the radial direction of the stopper plate 70 at locations corresponding to the second recess 77b, and connect the fitting hole 70a and the first adhesive-retaining recess 77, that is, they connect the radially inner and radially outer sides of the second annular projection 76. As a result, air AR1 and AR3 (see Figures 10 and 11) can pass through the communication grooves 76a when the rotor body 62 is attached to the magnet 63. In other words, the communication grooves 76a have the function of facilitating the flow of air AR1 and AR3 when the rotor body 62 is attached to the magnet 63. Therefore, it is possible to evenly distribute the adhesive GL between the rotor body 62 and the magnet 63.

[0057] [Rotor manufacturing method] Next, the manufacturing method of the rotor 60 that forms the brushless motor 10 as described above, that is, the assembly procedure of the rotor 60, will be explained in detail with reference to drawings. Prior to explaining the assembly procedure of the rotor 60, the assembly equipment used in the assembly work of the rotor 60 will be described.

[0058] The rotor 60 is formed by assembling a rotating shaft subassembly SS, consisting of a rotating shaft 61 and a rotor body 62, to a magnet subassembly MS, consisting of a magnet 63 and a stopper plate 70, as shown by the dashed arrow in Figure 8. The assembly apparatus 100 shown in Figures 9 to 13 is used for this assembly process.

[0059] As shown in Figure 9, the assembly device 100 includes first and second sliders 101 and 102 for holding the magnet sub-assembly MS, and a lifting member 103 for holding 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 can move closer to and further away from each other in the radial direction of the magnet sub-assembly MS by a movement mechanism (hydraulic or electric) not shown. The lifting member 103 can move up and down in the axial direction of the rotating shaft sub-assembly SS by a lifting mechanism (operated by hydraulics or electric) not shown.

[0060] As a result, the assembly device 100 can 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, to assemble the rotating shaft sub-assembly SS onto the magnet sub-assembly MS, or to remove 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 respect to the first and second sliders 101 and 102, which are interconnected. The first and second sliders 101 and 102 correspond to the first jig in this invention, and the lifting member 103 corresponds to the second jig in this invention.

[0062] [First Jig Setting Process] First, prepare the magnet 63 and the stopper plate 70. Next, abut the axial end of the magnet 63 (lower part in Figure 9) against the first annular projection 75 of the stopper plate 70, thereby forming the magnet subassembly MS.

[0063] Subsequently, as shown by arrow M1 in Figure 9, the first and second sliders 101 and 102 are moved closer together so as to sandwich the magnet sub-assembly MS from 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 onto the first and second sliders 101 and 102 is completed.

[0064] This completes the [first jig setting process].

[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 abutment 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 Figures 10 and 11) discharged from the abutment portion between the magnet 63 and the stopper plate 70 flows through each of the 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 subassembly SS, i.e., the bearing mounting portion 61c, is attached to the lifting member 103. This sets the rotating shaft subassembly SS to hang down from the lifting member 103. At this time, in order to allow the rotating shaft subassembly SS to be easily attached to the lifting member 103, a sufficient distance D1 is maintained between the fixed positions FP of the first and second sliders 101 and 102 and the movable position MP of the lifting member 103.

[0067] This completes the [second jig setting process].

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

[0069] [Adhesive application process] Next, a predetermined amount of adhesive GL is applied to the inner wall 63a of the axial base end side (upper side in Figure 9) of the magnet 63 that forms the magnet subassembly MS, in a ring-like manner, for one full rotation. Here, the amount of adhesive GL used is set so that, after the assembly of the rotor 60, it does not spill out radially outward from the stopper plate 70 and the magnet 63.

[0070] Furthermore, a predetermined amount of adhesive GL is applied to the outer wall 62a of the rotor body 62 at the axial tip side (lower side in Figure 9) of the rotor body 62 that forms the rotating shaft subassembly SS, in a ring-like manner, for one full rotation. Here, the amount of adhesive GL used is set to be such that, after the assembly of the rotor 60, it will slightly overflow onto the stepped portion DS (see Figure 5) at the axial base end side of the rotor body 62 and the magnet 63 (an amount that fits sufficiently within the ring-shaped space SP).

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

[0072] [Insertion Step] Next, drive the lifting mechanism of the assembly device 100 to move the lifting 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 lifting member 103 to approach the first and second sliders 101 and 102. Thereby, the tip side in the axial direction (the lower side in FIG. 9) of the rotating shaft 61 forming the rotating shaft sub-assembly SS faces the base 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 lifting member 103 gradually becomes shorter. Thereafter, as shown by the arrow M2 in FIG. 10, by continuously lowering the lifting member 103, the tip side in the axial direction of the rotor body 62 is inserted into the base 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 lifting 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] Subsequently, as shown by arrow M2 in Figures 10 and 11, when the axial tip of the rotor body 62 is continuously inserted into the axial base of the magnet 63, the air AR inside the magnet 63 (see Figures 9 to 11) flows as air AR1 between the middle 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, air AR2 flows through the connecting passage 75a of the first annular protrusion 75 (see Figure 7) and the air grooves 101a and 102a of the first and second sliders 101 and 102.

[0078] Furthermore, the multiple clearances CR between the large-diameter portion 61a of the rotating shaft 61 and the rotor body 62 are filled with 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 expelled to the outside, the adhesive GL spreads even 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 Figure 11. Subsequently, as shown by the dashed circle in Figure 11, the large diameter portion 61a of the rotating shaft 61 is fitted into the fitting hole 70a of the stopper plate 70.

[0081] As a result, the flow of air AR1, indicated by the dashed arrow, is blocked, and the flow of air AR2 and AR3, also indicated by the dashed arrow, is created. Here, the flow of air AR3 passes through the communication groove 76a (see Figure 7) of the second annular protrusion 76 and reaches multiple clearances CR, so the flow of air AR3 is smooth. Therefore, the flow of air AR2 and AR3 does not reduce the discharge efficiency 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 lifting member 103 becomes 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 a small amount, the adhesive GL that has passed beyond the second recess 77b due to the flow of the air AR2 reaches the second adhesive accommodating recess 78 through the communication passage 75a. Then, since the adhesive GL that has reached the second adhesive accommodating recess 78 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, it does not protrude outside the radial direction of the stopper plate 70 and the magnet 63.

[0085] As a result, 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 assembly device 100. Specifically, the movement mechanism of the assembly device 100 is driven to separate the first and second sliders 101 and 102 from each other, as shown by arrow M3 in Figure 13. This makes the rotor 60 removable from the first and second sliders 101 and 102.

[0087] Subsequently, the lifting mechanism of the assembly device 100 is driven to raise the lifting member 103, as shown by arrow M4 in Figure 13, and move it away from the first and second sliders 101 and 102. Specifically, in order 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 Figure 9 (D5 > D1).

[0088] Next, as shown by arrow M5 in Figure 13, the rotor 60, which is mounted to hang down from the lifting member 103, is removed from the lifting member 103. This removes the assembled rotor 60 (without the magnet support member 64 attached) from the assembly device 100, and the [removal process] is completed.

[0089] Here, either before or after the removal process, the assembled rotor 60 is heated to cure the adhesive GL. At this time, the air AR accumulated in the first adhesive-retaining recess 77 expands and tries to push the adhesive GL toward the second adhesive-retaining recess 78. However, the inner circumference of the rotor body 62 is provided with multiple clearances CR connected to the communication groove 76a (see Figure 7). Therefore, the air AR accumulated in the first adhesive-retaining recess 77 becomes a flow of air AR3 when the adhesive GL cures and is smoothly discharged to the outside through the multiple clearances CR. Thus, even when the adhesive GL cures, the adhesive GL does not bulge (overflow) radially outward from the stopper plate 70 and the magnet 63.

[0090] The magnet support member 64 (see Figure 5) is then attached to the removed rotor 60, thus completing the final assembly of the rotor 60.

[0091] As described in detail above, according to Embodiment 1, a first annular projection 75 is provided on the other side 74 of the stopper plate 70 in the portion facing the magnet 63, supporting the axial tip of the magnet 63; a second annular projection 76 is provided on the other side 74 of the stopper plate 70 in the portion facing the rotor body 62, supporting the axial tip of the rotor body 62; and a communication passage 75a is provided in the first annular projection 75, connecting the radially inner and radially outer sides of the first annular projection 75.

[0092] As a result, during the assembly of the rotor 60, air AR2 flows gently through the communication passage 75a provided in the first annular protrusion 75 of the stopper plate 70. Therefore, the adhesive GL that has spilled out into the first adhesive-retaining recess 77 on the radially inner side of the first annular protrusion 75 is prevented from forcefully spilling out into the second adhesive-retaining recess 78 on the radially outer side of the first annular protrusion 75. Thus, it is possible to improve the workability of the assembly process.

[0093] Furthermore, according to Embodiment 1, a total of six connecting passages 75a are provided at equal intervals (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 distributed in the circumferential direction of the stopper plate 70. Therefore, it is possible to eliminate the concentration of adhesive GL in one area, for example, by eliminating the need to wipe off excess adhesive GL after assembling the rotor 60.

[0094] Furthermore, according to Embodiment 1, a second adhesive receiving recess 78 is provided on the radially outer side of the first annular protrusion 75, recessed radially inward from the outer circumference of the magnet 63, and for accommodating adhesive GL that has overflowed from the communication passage 75a. This prevents adhesive GL that has passed through the communication passage 75a from overflowing radially outward from the stopper plate 70 and the magnet 63. This also reliably eliminates the need to wipe away excess adhesive GL after the rotor 60 has been assembled.

[0095] Furthermore, according to Embodiment 1, the protrusion height H of the first annular projection 75 from the other side surface 74 and the protrusion height H of the second annular projection 76 from the other side surface 74 are the same. Therefore, the adhesive GL that spills out from between the rotor body 62 and the magnet 63 is guided into the first adhesive receiving recess 77. Thus, the movement state of the spilled adhesive GL can be easily controlled.

[0096] Furthermore, according to Embodiment 1, 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 a stepped 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 protrudes from between the rotor body 62 and the magnet 63 can be contained in the annular space SP formed by the stepped portion DS.

[0097] Furthermore, according to Embodiment 1, when assembling the rotor 60, 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, respectively. Therefore, when inserting the axial tip side of the rotor body 62 into the axial base end side of the magnet 63, adhesive GL can be evenly distributed between the inner wall 63a of the magnet 63 and the outer wall 62a of the rotor body 62. At that time, since 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, 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 Embodiment 1, the assembly workability of the brushless motor 10 can be improved by eliminating the need to wipe off excess adhesive GL, thereby enabling energy savings in the manufacturing of the brushless motor 10. This makes it possible to achieve 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) of the United Nations Sustainable Development Goals (SDGs).

[0099] [Embodiment 2] Next, Embodiment 2 of the present invention will be described in detail with reference to the drawings. Parts having the same function as those in Embodiment 1 described above will be denoted by the same symbols, and their detailed descriptions will be omitted.

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

[0101] In Embodiment 2, the structure of the rotor 80 differs from that of Embodiment 1. Specifically, as shown in Figure 14, in the rotor 80 of Embodiment 2, the rotor body 62 is integrally provided on the outer circumference of the large-diameter portion 61a of the rotating shaft 61. In other words, in the rotor 80 of Embodiment 2, a portion of the radially outer side of the large-diameter portion 61a forms the rotor body 62.

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

[0103] As shown in Figure 14, in the rotor 80 of Embodiment 2, the length L1 of the rotor body 62 is longer than the length L2 of the magnet 63 (L1 > L2). Therefore, a stepped portion DS is formed on the axial base end side of the rotor body 62 and the magnet 63, and this stepped portion DS functions as an annular space SP.

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

[0105] Furthermore, in the rotor 80 of Embodiment 2, the magnet support member 64 (see Figure 5) that covers the outer circumference of the magnet 63 is omitted compared to the rotor 60 of Embodiment 1. This reduces the inertial mass of the rotor 80 and suppresses the increase in the rotational resistance of the rotor 80.

[0106] Furthermore, in the rotor 80 of Embodiment 2, the shape of the stopper plate 70 is different from that of the rotor 60 of Embodiment 1. Specifically, as shown in Figure 15, the thick cylindrical portion 73 provided on one side surface 72 of the large-diameter disc portion 71 does not have a material removal portion 73a (see Figure 6). This is because the stopper plate 70 of Embodiment 2 has a smaller diameter than the stopper plate 70 of Embodiment 1, so there is no concern about sink marks or voids occurring.

[0107] Furthermore, as shown in Figure 16, in the stopper plate 70 of Embodiment 2, a single annular projection 81 with a projection height H is provided on the other side 74 of the large-diameter disc portion 71. Here, the annular projection 81 consists of a first annular projection 75 and a second annular projection 76, and these first annular projection 75 and second annular projection 76 are formed by integrating them with each other. In Figure 16, a dashed line is drawn at the boundary between the first annular projection 75 and the second annular projection 76.

[0108] In the stopper plate 70 of Embodiment 2, the first annular projection 75 and the second annular projection 76 are integrated, so the first adhesive-retaining recess 77 (see Figure 7) of Embodiment 1 is not provided, and only the second adhesive-retaining recess 78 is provided on the radially outer side of the annular projection 81 (radially outer side of the first annular projection 75).

[0109] Furthermore, the annular protrusion 81, which consists of the first annular protrusion 75 and the second annular protrusion 76, has a total of six connecting passages 75a arranged at equal intervals (60-degree intervals) in the circumferential direction (see the dashed line in Figure 16). In other words, these connecting passages 75a are provided on both the first annular protrusion 75 and the second annular protrusion 76, and connect the radially inner and radially outer sides of the annular protrusion 81.

[0110] Here, air AR2 and adhesive GL pass through each communication passage 75a when the rotor body 62 is attached to the magnet 63 (see Figures 20 and 21). Furthermore, in the stopper plate 70 of Embodiment 2, the depth dimension DP2 of the second adhesive-retaining recess 78 in the radial direction of the stopper plate 70 (see Figure 16) is larger than the depth dimension DP1 of the second adhesive-retaining recess 78 in the stopper plate 70 of Embodiment 1 (see Figure 7) (DP2 > DP1). Therefore, the adhesive GL that has passed through the communication passage 75a can be contained more sufficiently.

[0111] [Rotor manufacturing method] In the manufacturing method of the rotor 80, the flow path of air AR2 in the later stages of the [bonding process] is slightly different from that of Embodiment 1. Specifically, as shown in Figure 18, after the flow of air AR1, indicated by the dashed arrow, is interrupted, only the flow of air AR2, also indicated by the dashed arrow, remains. Then, air AR2 flows to the second adhesive-retaining recess 78 through the respective connecting passages 75a (see Figure 16) provided in the annular protrusion 81.

[0112] Then, as shown by arrow M2 in Figure 19, as the insertion of the rotor body 62 into the magnet 63 continues, the axial end of the rotor body 62 (lower part in Figure 19) abuts against the second annular projection 76 that forms the annular projection 81. At this time, the adhesive GL that has protruded from the axial end of the rotor body 62 and the magnet 63 slowly passes through their respective connecting passages 75a (see Figure 16) along with the flow of air AR2.

[0113] Subsequently, the adhesive GL that has passed through each connecting passage 75a reaches the second adhesive-retaining recess 78. The adhesive GL that has reached the second adhesive-retaining recess 78 does not spill out radially outward from the stopper plate 70 and the magnet 63 because it has passed through the connecting passage 75a slowly and the depth dimension DP2 of the second adhesive-retaining recess 78 in the radial direction of the stopper plate 70 is sufficiently large.

[0114] In Embodiment 2, formed as described above, the same effects and advantages as in Embodiment 1 can be achieved. In addition, in Embodiment 2, the first annular projection 75 and the second annular projection 76 are integrated together as an annular projection 81, so the radial dimension of the stopper plate 70 can be reduced. This makes it possible to reduce the diameter of the rotor 80, thereby achieving further miniaturization of the brushless motor. Furthermore, since the magnet support member 64 (see Figure 5) that covers the outer circumference of the magnet 63 is omitted, the inertial mass of the rotor 80 can be reduced, and the increase in the rotational resistance of the rotor 80 can be suppressed. Therefore, it becomes possible to drive the brushless motor with low power consumption.

[0115] The present invention is not limited to the embodiments described above, and can be modified in various ways without departing from its essence. For example, the embodiments described above show a configuration with a total of six connecting passages 75a, but the present invention is not limited to this, and depending on the state of the adhesive GL that protrudes from between the rotor body 62 and the magnet 63, a total of two connecting passages or a total of seven or more connecting passages can be provided. Furthermore, the connecting passages 75a may be arranged at unequal intervals rather than at equal intervals in the circumferential direction of the stopper plate 70.

[0116] Furthermore, although the above-described embodiment shows the protrusion heights of the first annular projection 75 and the second annular projection 76 set to the same height H, the present invention is not limited to this, and the protrusion heights of the first annular projection 75 and the second annular projection 76 can be made different in order to control how much adhesive GL seeps out from between the rotor body 62 and the magnet 63.

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

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

[0119] 10: Brushless motor, 11: Driven object, 20: Case, 21: Cylindrical part, 22: Bottom wall part, 23: Opening, 24: Flange part, 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 part, 42: Insertion cylinder part, 43: Bearing holder, 44: Annular fixing plate, 45: Cylindrical wall part, 45a: Case opposing surface, 45b: Driven object opposing surface, 45c: Annular recess, 46: Driven object fixing part, 47: Case fixing part, 48: Cap nut, 49: Fitting cylinder part, 50: Sensor substrate, 51: Hall element, 60: Rotor, 61: Rotating shaft, 61a: Large diameter part, 61b: Medium diameter part, 61c: Bearing mounting part, 61d: Pinion gear part, 62: Rotor body, 62a: Outer wall, 63: Magnet, 63a: Inner wall, 64: Magnet support member, 64a: Bottom wall, 64b: Covering wall, 64c: Crimping part, 65: Sensor bracket, 70: Stopper plate (positioning member), 70a: Fitting hole, 71: Large diameter disc part, 72: One side, 73: Thick-walled cylinder part, 73a :Flesh-stealing section, 73b:Concave groove, 74:Other side (opposing section), 75:First annular protrusion, 75a:Communication passage, 76:Second annular protrusion, 76a:Communication groove, 77:First adhesive-retaining recess, 77a:First recess, 77b:Second recess, 78:Second adhesive-retaining recess (adhesive-retaining section), 80:Rotor, 81:Annular protrusion (single protrusion), 100:Assembly device, 101:First slider (first jig), 102:Second slider (second jig), 101a,102a:Air groove, 103:Lifting 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: Mating protrusion, CR: Clearance, DS: Step, FP: Fixed position, G: Recess, GL: Adhesive, MP: Movable position, MS: Magnet sub-assembly (sub-assembly), S1: First threaded member, S2: Second threaded 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 the stator, The rotor is The rotor body and The rotating shaft is rotated by the rotor body, A magnet fixed to the outer circumference of the rotor body with adhesive, A positioning member mounted on the rotating shaft, which positions the magnet and the rotor body in the axial direction of the rotating shaft, It has, The positioning member is provided with a first annular projection on the portion facing the magnet, which supports the axial tip of the magnet. The positioning member is provided with a second annular projection on the portion facing the rotor body, which supports the axial tip of the rotor body. The first annular projection is provided with a communication passage that connects the radially inner side and the radially outer side of the first annular projection. Brushless motor.

2. Multiple of the aforementioned connecting passages are provided at equal intervals in the circumferential direction of the first annular protrusion. The brushless motor according to claim 1.

3. In the brushless motor according to claim 1 or claim 2, On the radially outer side of the first annular protrusion, there is an adhesive receiving portion which is recessed radially inward from the outer circumference of the magnet and which contains the adhesive that has protruded from the communication passage. Brushless motor.

4. The protrusion height of the first annular projection from the opposing portion and the protrusion height of the second annular projection from the opposing portion are the same. The brushless motor according to claim 1.

5. The length of the rotor body in the axial direction of the rotating shaft is longer than the length of the magnet in the axial direction of the rotating shaft. The brushless motor according to claim 4.

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

7. The rotor body and The rotating shaft is rotated by the rotor body, A magnet is bonded and fixed to the outer circumference of the rotor body, A positioning member mounted on the rotating shaft, which positions the magnet and the rotor body in the axial direction of the rotating shaft, A method for manufacturing a rotor having the following: The positioning member is provided with a first annular projection on the portion facing the magnet, which supports the axial tip of the magnet. The positioning member is provided with a second annular projection on the portion facing the rotor body, which supports the axial tip of the rotor body. The first annular projection is provided with a communication passage that connects the radially inner side and the radially outer side of the first annular projection. The first jig setting step involves abutting the axial tip of the magnet against the first annular projection to form a sub-assembly, and then setting the sub-assembly into the first jig. A second jig setting step involves setting the axial base end of the rotating shaft onto a second jig that is provided coaxially with respect to the first jig, An adhesive application step of applying adhesive to the magnet and the rotor body, The insertion step involves moving at least one of the first jig and the second jig so that the axial tip of the rotating shaft faces the axial base of the magnet, and inserting the axial tip of the rotor body into the axial base of the magnet. The bonding step involves discharging the air inside the magnet to the outside of the magnet through the aforementioned communication passage, spreading the adhesive between the rotor body and the magnet, and bringing the axial tip of the rotor body into contact with the second annular projection, Equipped with, A method for manufacturing a rotor.

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

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