Motor device

Abstract

To enable electric connection between a terminal of a bus bar and a terminal of a terminal unit without using large-scaled facilities in a motor device.SOLUTION: A motor device has a stator accommodated in a housing and around which coil is wound, a rotor rotating with respect to the stator, a bus bar unit 50 provided on one side in an axial direction of the stator and having a plurality of bus bars, and a terminal 61 supplying drive current to the coil. The bus bar has an arc part formed in an arc shape, and a power supply connection part 51e projected to an outside in a radial direction of the arc part. The terminal 61 is arranged across an inside and an outside of the housing, and the power supply connection part 51e and the terminal 61 are overlapped in the axial direction of the rotor and arranged, and electrically connected by a bolt 28.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a motor device. [Background technology]

[0002] As a three-phase motor device mounted on a motorcycle or the like, a motor device in which a bus bar is interposed between a coil wound around each stator and a terminal unit facing a connector that connects to an external power source is known. As an example of the above motor device, the structure of a motor device in which the terminal of the bus bar and the terminal of the terminal unit are welded together is described in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-41871 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the motor device described in Patent Document 1, the terminals of the bus bars and the terminals of the terminal unit are welded to each other.

[0005] However, in the welding process between the bus bar terminals and the terminals, due to variations in each component, there is a large gap or misalignment between the bus bar terminals and the terminals when the terminal unit is assembled, making it difficult to weld the bus bar terminals and the terminals in a contacting state.

[0006] Furthermore, if welding is used, a welding machine and an image recognition camera are required, which poses the issue of the large-scale facilities required.

[0007] Therefore, a connection structure other than welding has been required for connecting the terminals of the bus bar and the terminals of the terminal unit.

[0008] An object of the present invention is to provide a motor device that enables electrical connection between the terminals of a bus bar and the terminals of a terminal unit without using large-scale equipment. [Means for solving the problem]

[0009] The motor device of the present invention includes a stator accommodated in a housing and wound with a coil, a rotor that rotates relative to the stator, a busbar unit provided on one axial side of the stator and including a plurality of busbars, and a terminal that supplies a drive current to the coil. unit a motor device having a circular arc portion formed in a circular arc shape, and a power supply connection portion protruding radially outward from the circular arc portion, the terminal unit includes a connector block fixed to the housing, and a plurality of terminals arranged in a circumferential direction inside the connector block and electrically connected to the power supply connection portion, The above Multiple The terminal is disposed across the inside and outside of the housing, and is connected to the power supply connection portion and the Multiple The terminals are arranged in a stacked manner in the axial direction of the rotor and are electrically connected by fastening members. Among the plurality of terminals, any one of the terminals has a one-way bent portion bent in one axial direction, and any one of the remaining terminals has an other-way bent portion bent in the other axial direction. . Effect of the Invention

[0010] According to the present invention, the terminals of the bus bar and the terminals of the terminal unit can be electrically connected without using large-scale equipment. [Brief description of the drawings]

[0011] [Figure 1] 1 is an external perspective view showing a structure of a motor device (brushless motor) according to an embodiment of the present invention. [Diagram 2] 2 is a plan view showing the internal structure of the motor device shown in FIG. 1 with a cover member removed. FIG. [Diagram 3] FIG. 3 is a cross-sectional view taken along the line AA shown in FIG. [Figure 4] 2 is a perspective view showing a bus bar unit and a drive connector to be assembled to the motor device shown in FIG. 1. [Diagram 5]2 is a partial plan view showing the structure of a connection portion between a bus bar unit and a drive connector in the motor device shown in FIG. [Figure 6] FIG. 6 is a cross-sectional view taken along line BB shown in FIG. [Figure 7] 7 is a partial perspective view showing the shape of a tip end of a power supply connection portion of the bus bar shown in FIG. 6. [Figure 8] 7 is a partial perspective view showing the shape of a tip end of a terminal of the driving connector shown in FIG. 6. [Figure 9] 6 is a partial cross-sectional view taken along line CC shown in FIG. 5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0013] The motor device shown in Figures 1 to 3 is a brushless motor 10 used as a drive source for an electric motorcycle or the like (a driven object). Specifically, the brushless motor 10 is mounted on a vehicle frame and drives the axle of a drive wheel via a chain or belt. Note that the brushless motor 10 can also be mounted directly on the axle of the drive wheel.

[0014] Brushless motor 10 includes a housing 20 that forms the outer shell of brushless motor 10. Housing 20 includes an aluminum housing main body 21 formed into a substantially cylindrical shape with a bottom, and an aluminum cover member 22 formed into a substantially disk shape. Here, cover member 22 closes the opening side of housing main body 21 (the upper side in FIGS. 1 and 3) via a gasket 23 (see FIGS. 1 and 3) that functions as a sealing member.

[0015] 3, a motor unit 40 is accommodated inside the housing 20. The motor unit 40 includes a stator 41 fixed to the inside of the housing body 21, and a rotor 42 that rotates via a minute gap (air gap) radially inside the stator 41. That is, the stator 41 is accommodated in the housing 20.

[0016] The stator 41 has a stator core 41a formed in a generally cylindrical shape by laminating a plurality of steel plates (magnetic material). A plurality of teeth (not shown) are provided on the radially inner side of the stator core 41a, and coils 41c corresponding to the three phases, U phase, V phase, and W phase, are wound around these teeth by concentrated winding or the like, via insulators 41b made of a non-magnetic material such as plastic. In other words, a plurality of coils 41c are wound around the stator 41.

[0017] Moreover, an annular busbar unit 50 is provided on one axial side of the stator 41 (above the axial direction SD in FIG. 3). The busbar unit 50 includes a plurality of busbars 51. The busbar unit 50 is electrically connected to the tip portions Tb (see FIG. 4) of the U-phase power terminal TU, the V-phase power terminal TV, and the W-phase power terminal TW. Here, the busbar unit 50 has a function of distributing a drive current to the coils 41c corresponding to the three phases of the U-phase, the V-phase, and the W-phase. That is, the U-phase power terminal TU, the V-phase power terminal TV, and the W-phase power terminal TW each supply a drive current to the coils 41c corresponding to the three phases of the U-phase, the V-phase, and the W-phase.

[0018] The rotor 42 rotates relative to the stator 41. The rotor 42 includes a rotor body 42a formed into a generally cylindrical shape by laminating a plurality of steel plates (magnetic bodies). A rotating shaft 42b made of a round steel bar is fixed to the center of rotation of the rotor body 42a. That is, the rotating shaft 42b rotates together with the rotor body 42a. A plurality of magnets 42c formed into a generally plate shape are provided inside the rotor body 42a. The magnets 42c are arranged such that the north pole and the south pole appear alternately in the circumferential direction of the rotor body 42a.

[0019] However, this is not limited to the so-called "IPM (Interior Permanent Magnet) structure" in which multiple magnets 42c are embedded inside the rotor body 42a as described above, but it is also possible to adopt a so-called "SPM (Surface Permanent Magnet) structure" in which a magnet (not shown) is attached to the surface of the rotor body 42a.

[0020] A sensor magnet 42d formed in a substantially disk shape is fixed to one axial side of a rotating shaft 42b forming the rotor 42. The sensor magnet 42d is used to detect the rotation state of the rotor 42 (rotating shaft 42b). The sensor magnet 42d faces a rotation sensor 44a provided on a sensor board 44 in the axial direction of the rotor 42.

[0021] One axial side of the rotating shaft 42b is rotatably supported by a first ball bearing BB1 mounted in a bearing holder 43. On the other hand, the other axial side (the lower side in FIG. 3) of the rotating shaft 42b is rotatably supported by a second ball bearing BB2 mounted in the housing body 21.

[0022] The housing body 21 has a bottom wall portion 21a formed in a substantially circular plate shape. A bearing mounting portion 21b and a seal mounting portion 21c formed in a substantially cylindrical shape are integrally provided at the center portion of the bottom wall portion 21a. The bearing mounting portion 21b and the seal mounting portion 21c are arranged coaxially. The bearing mounting portion 21b is provided on the inside of the housing body 21, and an outer ring of the second ball bearing BB2 is attached to the radially inner side of the bearing mounting portion 21b. In contrast, the seal mounting portion 21c is provided on the outside of the housing body 21, and a rubber lip seal LS is attached to the radially inner side of the seal mounting portion 21c.

[0023] The inner ring of the second ball bearing BB2 is attached to the other axial side of the rotating shaft 42b, and the lip seal LS is in contact with the outer periphery of the rotating shaft 42b at a portion closer to the outer side of the housing main body 21 than the second ball bearing BB2. This prevents rainwater, dust, and the like from entering the inside of the housing 20.

[0024] Furthermore, a total of four fixing legs 21d (only three are shown in Figs. 1 and 2) are provided on the outside of the housing body 21 and on the radially outer side of the bottom wall portion 21a. These fixing legs 21d are integrally provided at equal intervals (90 degree intervals) around the periphery of the bottom wall portion 21a and are fixed via bolts to a body frame or the like that forms the skeleton of the motorcycle.

[0025] Furthermore, the housing body 21 includes a cylindrical wall portion 21e formed in a substantially cylindrical shape. The other axial side of the cylindrical wall portion 21e is integrally provided on the radially outer side of the bottom wall portion 21a. The stator core 41a is press-fitted into the radially inner side of the cylindrical wall portion 21e and firmly fixed thereto by adhesive or the like. Furthermore, a plurality of cooling fins 21f are integrally provided on the radially outer side of the cylindrical wall portion 21e to radiate heat of the motor unit 40 (stator core 41a) generated by driving the brushless motor 10 to the outside of the housing body 21.

[0026] Furthermore, the housing body 21 includes a polygonal wall portion 24. The polygonal wall portion 24 is integrally provided on one axial side (the upper side in FIG. 3) of the cylindrical wall portion 21e so as to be coaxial with the cylindrical wall portion 21e. As shown in FIG. 2, the polygonal wall portion 24 is formed in a substantially regular hexagonal shape when the housing body 21 is viewed from one axial side.

[0027] Specifically, the polygonal wall portion 24 has a first side portion 24a, a second side portion 24b, a third side portion 24c, a fourth side portion 24d, a fifth side portion 24e, and a sixth side portion 24f, and these six sides 24a to 24f form a substantially regular hexagon. An opening portion 24g is provided in the polygonal wall portion 24, and the stator 41 and the rotor 42 (motor unit 40) are assembled into the housing main body 21 through the opening portion 24g. The opening portion 24g is sealed by the cover member 22 via the gasket 23.

[0028] A driving connector 25, which is a terminal unit, is attached to the first side 24a, and the driving connector 25 is provided on one axial side of the housing 20. The driving connector 25 has a connector block 25a made of a resin material such as plastic, and the driving connector 25 including the connector block 25a is fixed to the first side 24a of the polygonal wall portion 24 shown in Fig. 2 by a fixing bolt (another fastening member) 53 shown in Fig. 5, which will be described later.

[0029] The connector block 25a is disposed outside the housing 20, and specifically, protrudes radially outward from the polygonal wall portion 24. The connector block 25a has terminals 61 disposed therein. In detail, the base ends Tt (see FIG. 4) of the U-phase power terminal TU, the V-phase power terminal TV, and the W-phase power terminal TW are exposed inside the connector block 25a. The tip ends Tb (see FIG. 4) of the U-phase power terminal TU, the V-phase power terminal TV, and the W-phase power terminal TW are electrically connected to the bus bar units 50 accommodated inside the housing 20.

[0030] Specifically, the tip portions Tb of the U-phase power terminal TU, the V-phase power terminal TV, and the W-phase power terminal TW are electrically connected by fastening members to the power connection portions 51e (see FIG. 4) of the U-phase, V-phase, and W-phase bus bars 51. The electrical connection between each terminal 61 and each power connection portion 51e by fastening members will be described in detail later.

[0031] 2, one end of a U-phase electric wire EU is electrically connected to the controller CU at the base end Tt of the U-phase power terminal TU, while the other end of a V-phase electric wire EV is electrically connected to the controller CU at the base end Tt of the V-phase power terminal TV. Furthermore, one end of a W-phase electric wire EW is electrically connected to the controller CU at the base end Tt of the W-phase power terminal TW. This allows a drive current to be supplied to each coil 41c of the stator 41.

[0032] Each terminal 61, including the U-phase power terminal TU, the V-phase power terminal TV, and the W-phase power terminal TW, is arranged across the inside and outside of the polygonal wall portion 24 of the housing 20 in a plan view, as shown in Figures 3 and 5.

[0033] Here, the connector block 25a faces a direction intersecting with the axial direction of the housing 20 (upward in FIG. 2). In other words, the connection directions of the other ends of the U-phase, V-phase, and W-phase electric wires EU, EV, and EW to the drive connector 25 are each in a direction intersecting with the axial direction of the housing 20. The connector block 25a is fixed to the first side portion 24a via a rubber seal member SM (see FIG. 3). This prevents rainwater, dust, and the like from entering the inside of the housing 20 through the connector block 25a.

[0034] As shown in FIG. 2, the polygonal wall portion 24 is integrally provided with a protruding portion 26 that protrudes radially outward from the housing 20. Specifically, the protruding portion 26 protrudes radially outward from the second side portion 24b provided next to the first side portion 24a. The protruding portion 26 is formed in a substantially triangular shape when the housing 20 is viewed from one axial side, and includes an opening portion 26a and a bottom wall 26b that is formed in a substantially triangular shape. The protruding portion 26 also has a first side wall 26c and a second side wall 26d that stand from the bottom wall 26b to one axial side of the housing 20. The second side portion 24b also stands from the bottom wall 26b to one axial side of the housing 20.

[0035] In this manner, the protrusion 26 is surrounded by the bottom wall 26b, the first side wall 26c, the second side wall 26d, and the second side portion 24b, and a connection space SP is formed inside the protrusion 26. That is, the connection space SP is provided on one axial side of the housing 20.

[0036] The connection space SP is a portion into which the controller side connector portion 47 fits in the longitudinal direction of the board wire harness 45. The connection space SP has a function of guiding (guiding) the controller side connector portion 47 to the board connector 27 when the controller side connector portion 47 is connected to the board connector 27. This makes it possible to easily connect the controller side connector portion 47 to the board connector 27 when assembling the brushless motor 10.

[0037] Here, the first side wall 26c is disposed on a substantial extension of the first side portion 24a. The second side wall 26d is disposed on a substantial extension of the third side portion 24c. This prevents the protrusion 26 from protruding significantly radially outward from the housing 20. The opening 26a of the protrusion 26 is also sealed by the cover member 22 via the gasket 23.

[0038] 1 to 3, the cover member 22 includes a main cover portion 22a that closes the opening 24g of the polygonal wall portion 24, and a sub-cover portion 22b that closes the opening 26a of the protruding portion 26. The main cover portion 22a and the sub-cover portion 22b are integral with each other, and the main cover portion 22a is formed in a substantially circular plate shape, while the sub-cover portion 22b is formed in a substantially triangular plate shape.

[0039] The cover member 22 is firmly fixed to the housing main body 21 by a total of seven fixing bolts BT that are distributed around the circumference of the cover member 22. When the cover member 22 is fixed to the housing main body 21, a gasket 23 is sandwiched between them.

[0040] A connector fixing portion 26e is integrally provided on the first side wall 26c of the protruding portion 26 so as to protrude radially outward from the housing 20. A board connector 27 is attached to the connector fixing portion 26e. Here, the board connector 27 is also provided on one axial side of the housing 20, similar to the driving connector 25.

[0041] The board connector 27 is formed into a predetermined shape from a resin material such as plastic, and includes a fixing plate portion 27a formed in a substantially flat plate shape. The fixing plate portion 27a is fixed to the connector fixing portion 26e by a pair of first screws S1. A rubber seal member (not shown) is provided between the fixing plate portion 27a and the connector fixing portion 26e. This prevents rainwater, dust, and the like from entering the inside of the housing 20 through the board connector 27.

[0042] Furthermore, the board connector 27 includes an inner connection portion (not shown) formed in a substantially box shape and an outer connection portion 27c. The inner connection portion is provided on the connector fixing portion 26e side of the fixing plate portion 27a, and is disposed inside the housing 20. In contrast, the outer connection portion 27c is provided on the opposite side of the fixing plate portion 27a from the connector fixing portion 26e side, and is disposed outside the housing 20. Note that a plurality of conductive members (not shown) are embedded inside the board connector 27 by insert molding or the like.

[0043] Here, the controller side connector portion 47 of the board wire harness 45 is connected to the inner connection portion of the board connector 27 in the connection space SP inside the protrusion 26. Meanwhile, one end side of the board electric wire SE (see FIG. 2) electrically connected to the controller CU at the other end side is connected to the outer connection portion 27c of the board connector 27 via a connector connection portion (not shown). That is, the other end side of the board electric wire SE is electrically connected to one end side of a conductive member provided inside the board connector 27.

[0044] 1 and 2, connector block 25a arranged outside housing 20 and outer connection portion 27c also arranged outside housing 20 each face in a direction intersecting the axial direction of housing 20 and in the same direction (upward in FIG. 2). When housing 20 is viewed from a direction intersecting its axial direction, drive connector 25 and board connector 27 are arranged adjacent to each other in a horizontal row in a direction intersecting the axial direction of housing 20. This improves the ease of handling of U-phase, V-phase, and W-phase electric wires EU, EV, EW and board electric wire SE for brushless motor 10, and makes it possible to easily connect these electric wires EU, EV, EW, and SE to drive connector 25 and board connector 27, respectively.

[0045] Furthermore, when housing 20 is viewed from a direction intersecting the axial direction, drive connector 25 and board connector 27 are each provided within the range of the axial dimension of rotor 42, i.e., within the range of the axial dimension of rotating shaft 42b (see FIG. 3). This reduces the axial dimension of brushless motor 10, achieving a compact brushless motor 10.

[0046] 2 and 3, an aluminum bearing holder 43 formed in a substantially regular hexagonal plate shape is provided on one axial side (upper side in FIG. 3) of the housing body 21. The bearing holder 43 is disposed radially inside the polygonal wall portion 24 formed in a substantially regular hexagon shape, and holds a first ball bearing BB1. Specifically, the first ball bearing BB1 is mounted on a retaining tube 43a formed in the center of the bearing holder 43. The retaining tube 43a protrudes toward the other axial side (lower side in FIG. 3) of the housing body 21, and is inserted radially inside the busbar unit 50. This also reduces the axial dimension of the brushless motor 10.

[0047] The bearing holder 43 is firmly fixed to one axial side of the housing body 21 by a total of six first fixing bolts B1. The total of six first fixing bolts B1 are distributed so as to be located near the corners of the bearing holder 43, and are fastened from one axial side of the housing body 21. This effectively suppresses distortion of the bearing holder 43 and ensures the positional accuracy of the first ball bearing BB1. This allows the rotor 42 to rotate smoothly. The first fixing bolts B1 are provided inside the housing 20, and even if they become loose and come off, they will not fall off onto the rotor 42, reliably preventing damage to the rotating parts.

[0048] Further, a clip fixing portion 43b formed in a substantially plate shape is provided on the opposite side of the bearing holder 43 from the rotor 42 side and in the vicinity of the protruding portion 26. The clip fixing portion 43b is disposed between adjacent first fixing bolts B1 and protrudes to one axial side of the housing 20 (the front side in FIG. 2). A clip member 49 fixed to the board wire harness 45 is fixed to the clip fixing portion 43b.

[0049] Furthermore, an annular support plate 43c that prevents the first ball bearing BB1 from falling off the retaining cylinder 43a is provided in the center of the bearing holder 43 on the opposite side from the rotor 42. Specifically, the support plate 43c holds the outer ring of the first ball bearing BB1 with its radially inner portion. This ensures smooth operation of the first ball bearing BB1.

[0050] The support plate 43c is fixed to the bearing holder 43 by a total of four second fixing bolts B2 (only three are shown in FIG. 2) arranged at equal intervals (90 degree intervals) around the circumference of the support plate 43c. Here, the second fixing bolts B2 are also provided inside the housing 20, but even if they become loose and come off, they will not fall off onto the rotor 42, reliably preventing damage to the rotating parts.

[0051] Furthermore, a total of four support pillars 43d are provided around the first ball bearing BB1 on the side of the bearing holder 43 opposite the rotor 42. These support pillars 43d each protrude to one axial side of the housing 20 by a predetermined height, and a sensor board 44 is fixed to their tip portions. In other words, a total of four support pillars 43d support the sensor board 44.

[0052] Specifically, the support columns 43d are disposed at equal intervals (90 degree intervals) around the first ball bearing BB1, and the sensor board 44 is fixed to a pair of diagonally disposed support columns 43d by a pair of second screws S2. Note that the second screws S2 are also provided inside the housing 20, but even if they become loose and come off, they will not fall off onto the rotor 42, reliably preventing damage to the rotating portion.

[0053] The sensor board 44, supported by a total of four support columns 43d, is provided on one axial side of the housing 20 and is a printed circuit board (PCB) formed in a substantially square shape. A rotation sensor 44a made of a magnetic resistance element is provided in the center of the sensor board 44. The rotation sensor 44a faces a sensor magnet 42d fixed to one axial side of the rotating shaft 42b across a small gap in the axial direction of the housing 20 (see FIG. 3). In this way, the rotation sensor 44a detects the rotation state (rotation direction, rotation speed, etc.) of the rotating shaft 42b.

[0054] The sensor board 44 is provided with a board-side connection portion 44b to which a board-side connector portion 48 of the board wire harness 45 is connected. As shown in Fig. 2, the board-side connection portion 44b provided on the sensor board 44 is directed toward the connection space SP of the protrusion 26, which makes it possible to easily connect the board-side connector portion 48 to the board-side connection portion 44b.

[0055] Here, the board wire harness 45 is provided between the sensor board 44 and the board connector 27, and has a function of electrically connecting the controller CU (see FIG. 2) and the sensor board 44 inside the housing 20. Therefore, a detection signal of the rotation sensor 44a is sent to the controller CU via the board wire harness 45 and the board electric wire SE.

[0056] 3 and 4, the busbar unit 50 provided on one axial side of the stator 41 is formed in a generally annular shape when viewed in the axial direction. In a state in which the brushless motor 10 is assembled, a retaining cylinder 43a is disposed radially inside the busbar unit 50. Thus, the first ball bearing BB1 and a part of the rotating shaft 42b are also disposed radially inside the busbar unit 50.

[0057] The busbar unit 50 includes three busbars 51 formed in a substantially C-shape when viewed in the axial direction, and these busbars 51 are for the U-phase, V-phase, and W-phase (three-phase) coils 41c (see FIG. 3 ) corresponding to the U-phase, V-phase, and W-phase, respectively. Note that each of the three busbars 51 is formed in the same shape.

[0058] The busbar unit 50 also includes busbar support parts 52 that hold the busbars 51 for the U phase, the V phase, and the W phase. The busbar support parts 52 correspond to the insulators of the present invention, and are formed in an annular shape by injection molding a resin material such as plastic. Specifically, as shown in Fig. 4, the busbar support parts 52 hold the three busbars 51 on the same axis, each shifted by a predetermined amount (approximately 30 degrees) in the circumferential direction, and in a non-contact state (non-short-circuiting state) with each busbar 51 not in contact with each other.

[0059] The three bus bars 51 are stacked in an insulated state with small gaps between them in the axial direction of the bus bar unit 50. Therefore, distortion of each bus bar 51 is something that needs to be reliably eliminated during the manufacture of the bus bar unit 50. In other words, in order to reduce the axial dimension of the bus bar unit 50 and achieve a reduction in the overall size of the brushless motor 10, the bus bars 51 need to be precisely molded to prevent distortion.

[0060] Each busbar 51 has a first arc portion (arc portion) 51a and a second arc portion (arc portion) 51b formed in an arc shape when viewed in the axial direction of the busbar 51, and a power connection portion 51e protruding radially outward from each of the first arc portion 51a and the second arc portion 51b.

[0061] In detail, busbar 51 has a first arc portion 51a formed in a substantially arc shape when viewed in the axial direction of busbar 51. First arc portion 51a occupies most of busbar 51. Busbar 51 also has a second arc portion 51b formed in a substantially arc shape when viewed in the axial direction of busbar 51. Second arc portion 51b has the same radius of curvature as first arc portion 51a.

[0062] Coil connection portions 51c are integrally provided on both longitudinal sides of the first arc portion 51a and one longitudinal side of the second arc portion 51b. That is, a total of three coil connection portions 51c are provided on the bus bar 51. The interval between the pair of coil connection portions 51c provided on the first arc portion 51a is 180 degrees. The interval between the coil connection portion 51c on the other longitudinal side of the first arc portion 51a and the coil connection portion 51c of the second arc portion 51b is 90 degrees.

[0063] The ends Tb of the U-phase power terminal TU, the V-phase power terminal TV and the W-phase power terminal TW are electrically connected to the end Tp on the longitudinal end side of the power connection portion 51e.

[0064] Here, the connection between each terminal 61 and the power connection portion 51e corresponding to each terminal 61 in this embodiment by a fastening member will be described in detail. The U-phase power terminal TU (61) and the power connection portion 51e are arranged overlapping in the axial direction RD of the rotor 42 shown in FIG. 3. As shown in FIG. 5, the U-phase power terminal TU (61) and the power connection portion 51e are electrically connected by screwing of a fixing bolt 28, which is a fastening member. Similarly, the V-phase power terminal TV (61) and the power connection portion 51e are arranged overlapping in the axial direction RD of the rotor 42. As shown in FIG. 5, the V-phase power terminal TV (61) and the power connection portion 51e are electrically connected by screwing of a bolt 28, which is a fastening member. Also, the W-phase power terminal TW (61) and the power connection portion 51e are arranged overlapping in the axial direction RD of the rotor 42. As shown in FIG. 5, the W-phase power terminal TW (61) and the power connection portion 51e are electrically connected by threaded connection of a bolt 28, which is a fastening member.

[0065] Here, the details of the connection structure between each terminal 61 and the power connection portion 51e will be described using the connection structure between the V-phase power terminal TV (61) and the power connection portion 51e as a representative example. However, the connection structure between the U-phase power terminal TU (61) and the power connection portion 51e and the connection structure between the W-phase power terminal TW (61) and the power connection portion 51e are also similar to the connection structure between the V-phase power terminal TV (61) and the power connection portion 51e.

[0066] As shown in Fig. 6, in the connection structure between the V-phase power terminal TV (61) and the power connection portion 51e, the tip end of the power connection portion 51e is placed on the tip end of the V-phase power terminal TV (61), and a bolt 28 inserted from above the power connection portion 51e through the through hole 51i of the power connection portion 51e is screwed into the thread groove 61e of the V-phase power terminal TV (61) shown in Fig. 8. This electrically connects the V-phase power terminal TV (61) and the power connection portion 51e.

[0067] In the fastening structure shown in Fig. 6, the power supply connection portion 51e is disposed on the V-phase power supply terminal TV (61), and the bolt 28 inserted into the through hole 51i of the power supply connection portion 51e is screwed into the threaded groove 61e of the V-phase power supply terminal TV (61). Specifically, the V-phase power supply terminal TV (61) is formed with a threaded hole 61d as shown in Fig. 8, while the power supply connection portion 51e is formed with a through hole 51i as shown in Fig. 7, which has a larger diameter than the threaded hole 61d. The bolt 28 inserted into the through hole 51i of the power supply connection portion 51e is screwed into the threaded groove 61e of the V-phase power supply terminal TV (61), thereby electrically connecting the V-phase power supply terminal TV (61) and the power supply connection portion 51e.

[0068] The relationship between the V-phase power terminal TV (61) and the power connection portion 51e may be reversed. That is, the V-phase power terminal TV (61) may be placed on the power connection portion 51e, and a bolt 28 inserted from above the V-phase power terminal TV (61) through a through hole of the V-phase power terminal TV (61) is screwed into a threaded groove formed in the power connection portion 51e, whereby the power connection portion 51e and the V-phase power terminal TV (61) may be electrically connected to each other.

[0069] In this manner, in the brushless motor 10 of this embodiment, the connection between each terminal 61 and the power connection portion 51e corresponding to each terminal 61 is achieved by a screw fastening using the bolt 28, so that the power connection portion (terminal) 51e of the bus bar 51 can be electrically connected to each terminal 61 of the terminal unit (drive connector 25) without using large-scale equipment such as welding.

[0070] In addition, since the electrical connection between each terminal 61 and the power supply connection part 51e corresponding to each terminal 61 is made by screwing together a fastening member such as a bolt 28, a larger connection area can be secured compared to welding. This allows the current density of the current flowing through the connection part between the terminal 61 and the power supply connection part 51e to be lowered. Specifically, the brushless motor 10 mounted on a motorcycle or the like also flows a large current, so if the area is partially small and the current density is high at the connection part of the terminals, the resistance increases. This may cause the heat generation at the connection part during operation to exceed the heat resistance temperature of the coil coating, or the heat generation may be so large that it may have an adverse effect on the insert mold resin. Therefore, it is preferable that the current density at the connection part of the terminals is low. There is also a possibility that welding may not be able to secure a necessary and sufficient connection area (cross-sectional area) at the connection part of the terminals.

[0071] However, in brushless motor 10 of the present embodiment, the electrical connection between terminal 61 and power connection part 51e is made by screwing together a fastening member, so that a large connection area can be secured at the connection part and the like, and the current density of the current flowing at the connection part can be reduced. This makes it possible to prevent heat generation at the connection part during operation from increasing and exceeding the heat resistance temperature of the coil coating, and also prevents adverse effects on the insert mold resin due to excessive heat generation.

[0072] In addition, since the electrical connection between the terminal 61 and the power connection portion 51e is made by screwing together the fastening members, and no welding is performed, a welding machine or an image recognition camera is not required, and the amount of equipment used can be reduced.

[0073] In addition, in brushless motor 10 of the present embodiment, terminal 61 and power connection portion 51e are electrically connected by screwing a fastening member, and therefore welding is not performed, which reduces the need for machine tools to determine the welding position of terminal 61 and also reduces the driving energy of a welding machine for welding. As a result, it becomes possible to achieve Goals 7 and 13, in particular, of the Sustainable Development Goals (SDGs) established by the United Nations.

[0074] As shown in Fig. 6, a portion of the V-phase power terminal TV (61) that forms the thread groove 61e (see Fig. 8) is provided with a burnished portion 61f that is formed by burning and tapping. This can further increase the joining strength at the threaded joining portion between the bolt 28 and the thread groove 61e of the V-phase power terminal TV (61), and can also increase the connection strength between the terminal 61 and the power connection portion 51e.

[0075] In assembling the terminal 61 and the power connection portion 51e, when the tip end of the V-phase power terminal TV (61) and the tip end of the power connection portion 51e are overlapped, the V-phase power terminal TV (61) is inserted from the outside of the housing main body 21 toward the bus bar unit 50 inside the housing main body 21, and the tip end of the V-phase power terminal TV (61) and the tip end of the power connection portion 51e are overlapped. At this time, in the brushless motor 10 of the present embodiment, as shown in Fig. 7, a chamfered portion 51h is formed on the tip side peripheral portion 51f (periphery on the side of the tip portion Tp) of the surface (opposing surface 51d) of the power connection portion 51e that overlaps with the terminal 61 shown in Fig. 8.

[0076] Meanwhile, a chamfered portion 61c is formed on a tip-side peripheral portion 61b (peripheral portion on the tip portion Tb side) of a surface (opposing surface 61a) of the terminal 61 overlapping with the power supply connection portion 51e. This allows the terminal 61 and the power supply connection portion 51e to be assembled even if the terminal 61 and the power supply connection portion 51e ride up due to assembly variations in the axial direction RD of the rotor 42 shown in Fig. 3. That is, a chamfered portion 51h is formed on a tip-side peripheral portion 51f of the opposing surface 51d of the power supply connection portion 51e, and a chamfered portion 61c is formed on a tip-side peripheral portion 61b of the opposing surface 61a of the terminal 61. As a result, when the V-phase power terminal TV (61) is inserted from the outside of the housing body 21 and the end portion on the tip Tb side of the V-phase power terminal TV (61) and the end portion on the tip Tp side of the power connection portion 51e are overlapped, the chamfered portion 51h of the power connection portion 51e and the chamfered portion 61c of the V-phase power terminal TV (61) allow the terminal 61 and the power connection portion 51e to overlap smoothly. Therefore, even if the terminal 61 and the power connection portion 51e ride up each other, it is possible to assemble the terminal 61 and the power connection portion 51e.

[0077] As shown in FIG. 5, a connector block (connector) 25a that holds each terminal 61 is provided on the outside of the polygonal wall portion 24 of the housing 20 (see FIG. 3). Among the power supply connection portions 51e provided on each of the three bus bars 51 (see FIG. 4), the attachment portion 25b of the connector block (connector) 25a is disposed between two power supply connection portions 51e that are adjacently disposed in the circumferential direction AD of the first arc portion 51a (see FIG. 4). That is, in the structure shown in FIG. 5, a plate-shaped attachment portion 25b provided on the connector block 25a is disposed between the two power supply connection portions 51e that are adjacently disposed in the circumferential direction AD. This plate-shaped attachment portion 25b is inserted from the outside to the inside of the polygonal wall portion 24 of the housing 20 and disposed between the two adjacent power supply connection portions 51e.

[0078] 9, the plate-shaped mounting portion 25b is screwed to the housing main body 21 of the housing 20 via a bolt (another fastening member) 53. In detail, the bolt 53 is passed through an insert member 54 embedded in the mounting portion 25b, and the bolt 53 is screwed into a thread groove 21g formed in the housing main body 21. In other words, the connector block 25a is screwed to the housing main body 21 by the bolt 53 via the plate-shaped mounting portion 25b.

[0079] In this manner, the mounting portion 25b of the connector block 25a of the terminal unit is disposed between the two power connection portions 51e arranged adjacent to each other in the circumferential direction AD, thereby making it possible to efficiently utilize space and mount the terminal unit to the housing main body 21.

[0080] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention. In the above-described embodiment, the brushless motor 10 including the busbar unit 50 is applied to a drive source for an electric motorcycle or the like, but the present invention is not limited thereto. For example, the brushless motor 10 may be applied to a drive source for small mobility devices such as an electric wheelchair or an electric push cart, a drive source for joints of an arm robot, or even a drive source for a power steering device.

[0081] In addition, in the above embodiment, a case has been described in which the terminal 61 is subjected to burning processing to form a burning portion, but if the thickness of the terminal 61 is large and the length of the portion forming the screw groove 61e can be sufficiently secured, burning processing does not have to be performed.

[0082] Additionally, the material, shape, size, number, installation location, etc. of each component in the above-described embodiment may be arbitrary as long as it achieves the present invention, and is not limited to the above-described embodiment. [Explanation of symbols]

[0083] 10: brushless motor (motor device), 20: housing, 21: housing body, 21a: bottom wall portion, 21b: bearing mounting portion, 21c: seal mounting portion, 21d: fixed leg, 21e: cylindrical wall portion, 21f: cooling fin, 21g: screw groove, 22: cover member, 22a: main cover portion, 22b: sub-cover portion, 23: gasket, 24: polygonal wall portion, 24a: first side portion, 24b: second side portion, 24c: third side portion, 24d: fourth side portion, 24e: fifth side portion, 24f: sixth side portion, 24g: opening, 25: drive connector (terminal unit), 25a: connector block clip (connector), 25b: mounting portion, 26: protrusion, 26a: opening, 26b: bottom wall, 26c: first side wall, 26d: second side wall, 26e: connector fixing portion, 27: board connector, 27a: fixing plate portion, 27c: outer connection portion, 28: bolt (fastening member), 40: motor unit, 41: stator, 41a: stator core, 41b: insulator, 41c: coil, 42: rotor, 42a: rotor body, 42b: rotating shaft, 42c: magnet, 42d: sensor magnet, 43: bearing holder, 43a: retaining tube, 43b: clip fixing portion, 43c: support holding plate, 43d: support column, 44: sensor board, 44a: rotation sensor, 44b: board side connection part, 45: board wire harness, 47: controller side connector part, 48: board side connector part, 49: clip member, 50: busbar unit, 51: busbar, 51a: first arc part, 51b: second arc part, 51c: coil connection part, 51d: opposing surface, 51e: power supply connection part (terminal), 51f: tip side peripheral part, 51h: chamfered part, 51i: through hole, 52: busbar support part, 53: bolt (other fastening member), 54: insert member, 61: terminal, 61a : opposing surface, 61b: peripheral edge on tip side, 61c: chamfered portion, 61d: screw hole, 61e: screw groove, 61f: burning portion, AD: circumferential direction, B1: first fixing bolt, B2: second fixing bolt, BB1: first ball bearing, BB2: second ball bearing, BT: fixing bolt, CU: controller, EU: U-phase electric wire, EV: V-phase electric wire, EW: W-phase electric wire, LS: lip seal, RD: axial direction, S1: first screw, S2: second screw, SD: axial direction, SE: board electric wire, SM: seal material, SP: connection space, Tb: tip portion, Tp: tip portion, Tt: base end portion,TU: U-phase power terminal, TV: V-phase power terminal, TW: W-phase power terminal,

Claims

1. a stator housed in a housing and wound with a coil; a rotor that rotates relative to the stator; a busbar unit provided on one axial side of the stator and including a plurality of busbars; a terminal unit for supplying a driving current to the coil; A motor device having The bus bar is An arc portion formed in an arc shape; a power connection portion protruding radially outwardly of the arc portion; Equipped with The terminal unit includes: a connector block secured to the housing; a plurality of terminals arranged in a circumferential direction inside the connector block and electrically connected to the power supply connection portion; Equipped with The plurality of terminals are disposed across the inside and outside of the housing, the power supply connection portion and the plurality of terminals are arranged in an axial direction of the rotor in a stacked manner and are electrically connected to each other by fastening members; A motor device characterized in that any one of the plurality of terminals has a one-way bent portion bent in one axial direction, and any one of the remaining terminals has an other-way bent portion bent in the other axial direction.

2. a chamfered portion is formed on a peripheral edge of a tip end of a surface of the power supply connection portion that overlaps with the plurality of terminals; 2. The motor device according to claim 1, wherein a chamfer is formed on a peripheral edge of a tip end of each of the surfaces of the plurality of terminals that overlaps with the power supply connection portion.

3. A screw hole is formed in the plurality of terminals, A through hole having a diameter larger than that of the screw hole is formed in the power supply connection portion, 3. The motor device according to claim 1, wherein a fixing bolt passed through the through hole and a thread groove formed in the screw hole are screwed together.

4. the connector block for holding the plurality of terminals is provided on the outside of the housing, an attachment portion of the connector block is disposed between two of the power supply connection portions that are adjacent to each other in a circumferential direction of the arc portion, among the power supply connection portions that each of the plurality of bus bars includes; 4. The motor device according to claim 1, wherein the mounting portion is fixed to the housing via another fastening member.

Images