Motor

Abstract

A motor (1) is provided with: a conductive wire (28a) that forms a coil (28); and a metal member (46) that has a first surface (50a) that contacts the conductive wire (28a), and a second surface (51b) that overlaps the first surface (50a). The conductive wire (28a) is fitted into a groove (52) formed in the first surface (50a), and the conductive wire (28a) is crimped while being surrounded by the first surface (50a) and the second surface (51b).

Description

motor

[0001] The present invention relates to a motor.

[0002] For example, Patent Document 1 discloses a technique for facilitating coupling between a lead wire of a coil and a connection terminal in a motor.

[0003] JP 2009-38938 A

[0004] To further improve the electrical connection between the lead wires and the connection terminals, it is necessary to improve the strength of the mechanical bond between the lead wires and the connection terminals.

[0005] Therefore, one of the objects of the present invention is to provide a motor that can improve the mechanical strength of the connection of the conductor wires.

[0006] A motor according to a first aspect of the present invention comprises a metal member having a conductor forming a coil, a first surface in contact with the conductor, and a second surface overlapping the first surface, wherein the conductor is fitted into a groove formed in the first surface, and the conductor is surrounded and crimped by the first surface and the second surface.

[0007] A motor according to a second aspect of the present invention includes a plurality of conducting wires forming a plurality of coils, a plurality of bus bars electrically connected to the plurality of coils in the direction of the rotation axis, and a member having a plurality of portions that guide some of the plurality of conducting wires between the plurality of coils and the plurality of bus bars in the direction of the rotation axis, the plurality of portions of the member being adhered to some of the plurality of conducting wires.

[0008] 1 is a perspective view schematically illustrating the structure of a motor 1 according to an embodiment of the present invention. FIG. 1 is a cross-sectional view taken along line 2-2 of FIG. 1. FIG. 2 is a cross-sectional view taken along line 3-3 of FIG. 2. FIG. 3 is a perspective view schematically illustrating the structure of a stator assembly 25 according to a specific example. FIG. 4 is a perspective view taken from above showing an example of an electrical connection between an outer terminal 46 and a coil 28. FIG. 5 is a perspective view taken from below showing an example of an electrical connection between an outer terminal 46 and a coil 28. FIG. 6 is a perspective cross-sectional view taken along line 7-7 of FIG. 8. FIG. 7 is a cross-sectional view taken along line 8-8 of FIG. 5. FIG. 8 is a perspective view illustrating a state in which the outer terminal 46 and the conductor 28a are coupled to each other. FIG. 9 is a perspective view illustrating a state in which the outer terminal 46 and the conductor 28a are coupled to each other. FIG. 10 is a perspective view schematically illustrating the structure of a stator assembly 25A according to another specific example. FIG. 11 is a perspective view taken along line 13-13 of FIG. 12. FIG. 12 is a perspective view illustrating a state in which the terminal 70 and the conductor 28a are coupled to each other. FIG. 13 is a perspective view schematically illustrating the structure of a stator assembly 25B according to yet another specific example. 1 is an exploded perspective view schematically illustrating the structure of a stator assembly 25B with the busbar unit 40 removed. FIG. 2 is an exploded perspective view schematically illustrating the structure of a busbar unit 40A according to another specific example. FIG. 3 is a partially enlarged perspective view schematically illustrating the structure of a stator assembly 25B. FIG. 4 is a perspective view schematically illustrating the structure of an annular member 8 according to a specific example. FIG. 5 is a partially enlarged perspective view showing how a coil 28 is coupled to the annular member 8. FIG. 6 is a perspective view schematically illustrating the structure of a stator assembly 25C according to yet another specific example. FIG. 7 is a partially enlarged perspective view schematically illustrating the structure of the stator assembly 25C. FIG. 8 is a perspective view schematically illustrating the structure of an annular member 9 according to a specific example. FIG. 9 is a partially enlarged plan view schematically illustrating the structure of one outer portion 93 and one inner portion 94. FIG. 10 is a partially enlarged bottom view schematically illustrating the structure of one outer portion 93 and one inner portion 94. FIG. 11 is a partially enlarged plan view schematically illustrating how the annular member 8 holds the conducting wires 28a. FIG. 12 is a perspective view schematically illustrating the structure of an annular member 9A according to a modified example. FIG. 10 is a partially enlarged perspective view schematically illustrating the structure of an outer terminal 46B according to a modified example.1 is a partially enlarged plan view schematically showing the structure of an outer terminal 46B according to a modified example. FIG. 2 is a partially enlarged plan view for explaining electrical connection of a conductor 28a to the outer terminal 46B. FIG. 3 is a partially enlarged plan view schematically showing the structure of a modified example of the outer terminal 46B. FIG. 4 is a partially enlarged perspective view schematically showing the structure of a modified example of the outer terminal 46A. FIG. 5 is a partially enlarged perspective view schematically showing the structure of a modified example of the outer terminal 46A. FIG. 6 is a partially enlarged perspective view schematically showing the structure of a modified example of the outer terminal 46A. FIG. 7 is a partially enlarged perspective view schematically showing the structure of a modified example of the outer terminal 46B. FIG. 8 is a partially enlarged perspective sectional view schematically showing the structure of a motor 1 according to another embodiment of the present invention.

[0009] An embodiment of the present invention will now be described with reference to the accompanying drawings. Fig. 1 is a perspective view that schematically shows the structure of a motor 1 according to an embodiment of the present invention. Fig. 2 is a vertical sectional view that schematically shows the structure of a motor 1 according to an embodiment of the present invention. Fig. 3 is a horizontal sectional view that schematically shows the structure of a motor 1 according to an embodiment of the present invention. Note that Fig. 2 corresponds to a sectional view taken along line 2-2 in Fig. 1, along an imaginary plane that includes an axis x that constitutes the rotational axis of the motor 1. Fig. 3 corresponds to a sectional view taken along line 3-3 in Fig. 2, along an imaginary plane that is perpendicular to the axis x.

[0010] In the following description of the embodiment of the motor 1, one side in the direction along the axis x (hereinafter referred to as the "rotational axis direction") is defined as the upper side, and the other side opposite the one side as the lower side. These upper and lower sides defined in the rotational axis direction do not necessarily coincide with the up-and-down relationship in the direction of gravity. Furthermore, the radial direction of the motor 1 is defined as a direction perpendicular to the axis x. In this radial direction, the side away from the axis x is defined as the outer side (outer circumferential side) in the radial direction, while the side approaching the axis x is defined as the inner side (inner circumferential side) in the radial direction. Furthermore, the circumferential direction of the motor 1 is defined around the axis x.

[0011] 1 to 3, the motor 1 includes, for example, a cylindrical shaft 10 whose central axis is axis x. The shaft 10 is rotatably supported by two bearings 12 and 13 fixed to a housing 11. The bearings 12 and 13 are attached between the shaft 10 and the housing 11 by, for example, press fitting. The bearings 12 and 13 are, for example, ball bearings. In this example, the shaft 10 protrudes downward from the bottom end of the housing 11 farther than it protrudes upward from the top end of the housing 11.

[0012] The housing 11 has, for example, a cylindrical main body (hereinafter referred to as the "housing main body") 14 and, for example, a disk-shaped cover 15. The lower end of the housing main body 14 is open, while the upper end of the housing main body 14 is closed by the housing main body 14 having an upper portion. The lower end of the housing main body 14 is covered and closed by the cover 15. The shaft 10 protrudes outside the housing 11 from an opening 16 formed at the upper end of the housing main body 14 and an opening 17 formed in the cover 15. A flange 14a protruding in a predetermined shape in the radial direction is formed at the lower end of the housing main body 14. This flange 14a is used, for example, to attach the motor 1 to a predetermined application.

[0013] A cylindrical rotor core 18, for example, is fixed to the shaft 10 between the bearings 12, 13 in the rotational axis direction. The rotor core 18 is formed from a laminate of multiple magnetic materials stacked in the rotational axis direction. As is clear from FIG. 3 , the rotor core 18 has, for example, a cylindrical inner peripheral portion 19 with its central axis coincident with the axis x, a cylindrical outer peripheral portion 20 with its central axis coincident with the axis x, and multiple connection portions 21 connecting the inner peripheral portion 19 and the outer peripheral portion 20 to each other. The rotor core 18 is fixed by inserting the shaft 10 into a hole formed in the inner peripheral portion 19 along the axis x. Each connection portion 21 is formed, for example, in the shape of a vertically elongated flat plate extending in the radial direction.

[0014] A plurality of magnets 22 are embedded in the outer peripheral portion 20 of the rotor core 18 in close proximity to its outer peripheral surface. The magnets 22 are, for example, permanent magnets. Each magnet 22 is fixed, for example, in a through-hole 23 in the outer peripheral portion 20 that extends in the direction of the rotation axis in close proximity to the outer peripheral surface of the rotor core 18. The magnets 22 are arranged in the circumferential direction, with their magnetic poles oriented alternately as north and south poles in the circumferential direction. This motor 1 is a so-called interior permanent magnet (IPM) motor. The rotor core 18 and the magnets 22 form a rotor 24 of the motor 1. In other words, the motor 1 is an inner rotor type motor.

[0015] A stator assembly 25 is housed within the housing 11. The stator assembly 25 includes a stator core 26, a plurality of insulators 27, and a plurality of coils 28. The stator core 26 is fixed to the inner peripheral surface of the housing main body 14. A plurality of coils 28 are arranged in the circumferential direction and wound around the insulators 27 of the stator core 26. The stator core 26 is formed from a laminated body of a magnetic material such as silicon steel plate. The coils 28 are formed from, for example, conductive wires 28a having a predetermined diameter. The insulators 27 are formed from an insulating material such as a resin material. The insulators 27, which are arranged between the stator core 26 and the coils 28, insulate the stator core 26 from the coils 28.

[0016] As shown in FIG. 3 , the stator core 26 has a cylindrical tubular portion 29 and a plurality of teeth 30. The outer peripheral surface of the tubular portion 29 is fixed to the inner peripheral surface of the housing main body 14. Each tooth 30 has a spoke 31 and a magnetic pole portion 32. The spoke 31 extends radially from its outer peripheral end to its inner peripheral end. The magnetic pole portions 32 are continuous with the inner peripheral ends of the spokes 31. The magnetic pole portions 32 protrude circumferentially in opposite directions from each other from the spoke 31. The inner peripheral surfaces of the magnetic pole portions 32 of the teeth 30 face the outer peripheral surface of the outer peripheral portion 20 of the rotor core 18 with a predetermined magnetic gap between them. A conductor 28 a is wound around each spoke 31 via an insulator 27 to form a coil 28. The stator core 26, the insulator 27, and the coil 28 constitute a stator 33 of the motor 1.

[0017] FIG. 4 is a perspective view schematically illustrating the structure of a stator assembly 25 according to one specific example. Referring to FIGS. 2 and 4 together, the stator assembly 25 includes a busbar unit 40. The busbar unit 40 is disposed between the coil 28 and the upper end of the housing main body 14. The busbar unit 40 includes an annular housing 41 and a busbar group 42 serving as a conductive member housed within the housing 41. The busbar unit 40 is configured to supply current to the coil 28 from an external power source (not shown) via the busbar group 42. Note that the housing 41 of the busbar unit 40 is not illustrated in FIG. 4. That is, only the busbar group 42 of the busbar unit 40 is visible in FIG.

[0018] The bus bar group 42 includes a plurality of first bus bars 43 and a plurality of second bus bars 44. In this example, three first bus bars 43 are stacked in the rotational axis direction, while six second bus bars 44 are arranged circumferentially below the first bus bars 43 in the rotational axis direction. Each first bus bar 43 includes an annular portion (hereinafter referred to as an "annular portion") 45, a plurality of terminals (metal members; hereinafter referred to as "outer terminals") 46 extending radially outward from the annular portion 45, and terminals (hereinafter referred to as "external terminals") 47 extending upward from the annular portion 45. Meanwhile, each second bus bar 44 includes a main body 48 extending in an arc shape in the circumferential direction and a plurality of terminals (metal members; hereinafter referred to as "inner terminals") 49 extending radially inward from the main body 48. The outer terminals 46 protrude radially outward from the housing 41, while the inner terminals 49 protrude radially inward from the housing 41.

[0019] The plurality of outer terminals 46 and the plurality of inner terminals 49 are electrically connected to the conductors 28a of the coils 28 based on a predetermined wiring circuit. Thus, one end of the conductors 28a forming each coil 28 is electrically connected to the first bus bar 43, while the other end of the conductors 28a is electrically connected to the second bus bar 44. The external terminals 47 are electrically connected to an external device (not shown). The external device may include a power source that supplies current to the motor 1. As shown in FIGS. 1 and 2 , the external terminals 47 protrude upward from the housing main body 14 to the outside of the housing 11. In this example, three external terminals 47 are arranged at equal intervals in the circumferential direction. Each external terminal 47 is electrically connected to an external device via wiring (not shown) or the like.

[0020] FIG. 5 is a perspective view from above showing an example of an electrical connection between the outer terminal 46 and the coil 28. FIG. 6 is a perspective view from below showing an example of an electrical connection between the outer terminal 46 and the coil 28. FIG. 7 is a perspective cross-sectional view taken along line 7-7 in FIG. 8. FIG. 8 is a cross-sectional view taken along line 8-8 in FIG. 5. For simplicity, FIGS. 5 to 8 only show a portion of the conductor 28a and a portion of the first bus bar 43. FIGS. 5 to 8 illustrate the electrical connection between the outer terminal 46 and the conductor 28a of the coil 28. The electrical connection between the outer terminal 46 and the conductor 28a of the coil 28 will be described below, but the electrical connection between the inner terminal 49 and the conductor 28a of the coil 28 is configured in a similar manner. The cross section in FIG. 7 is a cross-section of one first bus bar 43 taken along an imaginary plane perpendicular to the axis x.

[0021] 5 to 8 , each outer terminal 46 has a first portion 50 extending in a first direction from the annular portion 45 of the first bus bar 43, and a second portion 51 extending from the first portion 50 in a second direction intersecting the first direction. In this example, the first direction is the radial direction, and the second direction is the tangential direction of a circle defined around the axis x. That is, in this example, the first direction and the second direction are perpendicular to each other. Both the first portion 50 and the second portion 51 are formed, for example, in a flat plate shape. The second portion 51 is connected to one end of the first portion 50 in the second direction. The first portion 50 and the second portion 51 are integrally formed, for example, from a conductive metal material. The second portion 51 is formed by bending the first portion 50. That is, the second portion 51 is connected to the first portion 50 in a bendable manner.

[0022] The first portion 50 has an upper surface (first surface) 50a and a lower surface 50b that face each other. In this example, the upper surface 50a and the lower surface 50b are parallel to each other. The upper surface 50a is continuous with the upper surface of the annular portion 45, and the lower surface 50b is continuous with the lower surface of the annular portion 45. The upper surface 50a has a groove 52 extending in a first direction and a slit 53 extending in the first direction and connecting to the groove 52. The slit 53 extends from the outer peripheral end of the first portion 50 toward the inner peripheral side. In this example, the groove 52 and the slit 53 extend radially on the same straight line. The groove 52 has, for example, a semicircular cross section in a plane perpendicular to the axis extending in the longitudinal direction of the groove 52. The slit 53 penetrates from the upper surface 50a to the lower surface 50b. The outer peripheral end of the first portion 50 has two portions 54, 54 (hereinafter referred to as "outer ends").

[0023] The second portion 51 covers the first portion 50 from above in an area other than the outer end 54. In this example, the second portion 51 extends from one end of the first portion 50 in the second direction beyond the other end (see FIG. 8 ). That is, the width of the second portion 51 in the second direction is similarly set larger than the width of the first portion 50 in the second direction. The second portion 51 has an upper surface 51a and a lower surface (second surface) 51b facing each other. In this example, the upper surface 51a and the lower surface 51b are set parallel to each other. The upper surface 51a is continuous with the lower surface 50b of the first portion 50, and the lower surface 51b is continuous with the upper surface 50a of the first portion 50. The lower surface 51b overlaps the upper surface 50a of the first portion 50. The conducting wire 28a of the coil 28 rises upward in the rotation axis direction and extends into the slit 53 of the first portion 50.

[0024] In this example, the conductor 28a has, for example, a circular cross section. The conductor 28a is disposed at the inner end within the slit 53. In the first portion 50, the outer ends 54, 54 are crimped in a direction that brings them closer to each other in the circumferential direction, thereby crimping the conductor 28a between the outer ends 54, 54. Furthermore, the conductor 28a is fitted into the groove 52 by being bent inward within the slit 53. In this example, approximately the upper half of the conductor 28a is exposed above the upper surface 50a of the first portion 50. The conductor 28a is in contact with the upper surface 50a of the first portion 51 and the lower surface 51b of the second portion 51. In this manner, the conductor 28a is surrounded by the upper surface 50a of the first portion 50 and the lower surface 51b of the second portion 51. In this example, the lower surface 51 b of the second portion 51 is bent toward the upper surface 50 a of the first portion 50 , so that the conductive wire 28 a is crimped between the first portion 50 and the second portion 51 .

[0025] 9 and 10 are perspective views illustrating the process of connecting the outer terminal 46 and the conductor 28a to each other. For simplicity, only a portion of the conductor 28a of the coil 28 and a portion of the first bus bar 43 are shown in FIGS. 9 and 10 . As shown in FIGS. 9 and 10 , an intermediate product 43A of the first bus bar 43 is prepared. In this intermediate product 43A, the second portion 51 is not bent relative to the first portion 50. That is, the lower surface 51b of the second portion 51 is coplanar with the upper surface 50a of the first portion 50. The upper surface 50a is connected to the lower surface 51b. The upper surface 51a of the second portion 51 is coplanar with the lower surface 50b of the first portion 50. This intermediate product 43A can be easily formed, for example, by stamping a metal plate. During the stamping process, the groove 52 in the upper surface 50a of the first portion 50 is formed by half-punching.

[0026] Meanwhile, the conductor 28a of the coil 28 is not bent either. That is, the conductor 28a stands straight upward in the direction of the rotation axis. In this state, as shown in FIG. 9 , the intermediate product 43A (busbar unit 40, i.e., first busbar 43) is positioned relative to the coil 28 so that the slits 53 of each outer terminal 46 receive the conductor 28a. The conductor 28a is inserted up to the inner end of the slit 53 of the first portion 50. In this state, as shown in FIG. 10 , the outer ends 54, 54 of the first portion 50 are crimped by a predetermined crimping jig (not shown) so that they approach each other in the circumferential direction. In this example, the outer ends 54, 54 approach each other as they approach the outer end. In this manner, the conductor 28a is crimped by the outer ends 54, 54.

[0027] The conductor 28a is then bent from its inner circumferential end of the slit 53 toward the groove 52. The tip of the conductor 28a is completely accommodated within the groove 52. In this example, a gap is formed between the inner circumferential end of the groove 52 and the tip of the conductor 28a. Approximately half of the lower side of the conductor 28a is accommodated within the groove 52. In this state, the second portion 51 is bent along one circumferential end of the first portion 50 using a predetermined crimping tool (not shown). As a result, as shown in FIGS. 5, 6, and 8, the lower surface 51b of the second portion 51 is pressed against the upper surface 50a of the first portion 50. As a result, the lower surface 51b of the second portion 51 crimps the conductor 28a between itself and the upper surface 50a of the first portion 50. In this manner, the outer terminal 46 and the conductor 28a are coupled together.

[0028] In the motor 1 described above, electrical connection between the conductor 28a forming the coil 28 and the outer terminal 46 of the first bus bar 43 is established by crimping the conductor 28a between the first portion 50 and the second portion 51 of the outer terminal 46. Specifically, the conductor 28a is fitted into a groove 52 formed in the first portion 50, and the conductor 28a is crimped while surrounded by the upper surface 50a of the first portion 50 and the lower surface 51b of the second portion 51. This improves the strength of the mechanical bond between the conductor 28a and the outer terminal 46. As a result, the electrical connection between the conductor 28a and the outer terminal 46 is also improved. Furthermore, because the bent conductor 28a is fitted into the groove 52, the conductor 28a is prevented from coming loose from the outer terminal 46. To further improve the electrical connection, soldering or welding may be performed along the boundary between the outer terminal 46 and the conductor 28a.

[0029] FIG. 11 is a perspective view schematically illustrating the structure of a stator assembly 25A according to another example. This stator assembly 25A incorporates a connecting plate 60 as a substrate, instead of the busbar unit 40 described above. The connecting plate 60 has a main body 61 extending in an annular shape around the axis x. The main body 61 is formed with holes 62 parallel to the axis x. The holes 62 penetrate the main body 61 in the direction of the rotation axis. Each of the holes 62 holds a terminal (metal member) 70 extending in the direction of the rotation axis. The upper end of the terminal 70 protrudes upward from the main body 61. Meanwhile, the lower end of the terminal 70 is inserted into a recess 27a formed in the upper end of the insulator 27. The upper end of the terminal 70 holds a conductor 28a, which is a spare wire for the coil 28. Note that the same components as those in the above-described embodiment are designated by the same reference numerals, and redundant description will be omitted here.

[0030] FIG. 12 is a perspective view schematically illustrating the structure of a terminal 70 according to one specific example. FIG. 13 is a cross-sectional view taken along line 13-13 in FIG. 12. Referring to both FIGS. 12 and 13, the terminal 70 in this example has a first portion 71 extending in a first direction and a second portion 72 extending from the first portion 71 in a second direction intersecting the first direction. In this example, the first direction is the rotation axis direction, and the second direction is the tangent direction of a circle defined around the axis x. In this example, the first direction and the second direction are perpendicular to each other. Both the first portion 71 and the second portion 72 are formed, for example, in a flat plate shape. The second portion 72 is connected to one end of the first portion 71 in the second direction. The first portion 71 and the second portion 72 are integrally formed, for example, from a conductive metal material. The second portion 72 is connected to the first portion 71 in a bendable manner.

[0031] The first portion 71 has an outer surface (first surface) 71a and an inner surface 71b that face back to back. In this example, the outer surface 71a and the inner surface 71b are defined parallel to each other. The outer surface 71a has a groove 73 extending in the first direction and a slit 74 extending in the first direction and connecting to the groove 73. The slit 74 extends downward from the upper end of the first portion 71. In this example, the groove 73 and the slit 74 extend on the same straight line in the rotation axis direction. The groove 73 has, for example, a semicircular cross section in a plane perpendicular to the axis extending in the longitudinal direction of the groove 73. The slit 74 penetrates from the outer surface 71a to the inner surface 71b. Thus, the upper end of the first portion 71 has two portions (hereinafter referred to as "upper end portions") 75, 75.

[0032] The second portion 72 covers the outer periphery of the first portion 71 in an area other than the upper end portion 75. In this example, the second portion 72 extends from one end of the first portion 71 in the second direction beyond the other end. That is, the width of the second portion 72 in the second direction is similarly set larger than the width of the first portion 71 in the second direction. The second portion 72 has an outer surface 72a and an inner surface (second surface) 72b facing back to back. In this example, the outer surface 72a and the inner surface 72b are set parallel to each other. The outer surface 72a is continuous with the inner surface 71b of the first portion 71, and the inner surface 72b is continuous with the outer surface 71a of the first portion 71. The inner surface 72b overlaps the outer surface 71a of the first portion 71. The conducting wire 28a of the coil 28 extends radially into the slit 74 of the first portion 71.

[0033] The conductor 28a is disposed at the lower end within the slit 74. In the first portion 71, the upper ends 75, 75 are crimped toward each other in the circumferential direction, thereby crimping the conductor 28a between the upper ends 75, 75. Furthermore, the conductor 28a is fitted into the groove 73 by being bent inward within the slit 74. In this example, approximately half of the outer periphery of the conductor 28a is exposed outward from the outer surface 71a of the first portion 71. The conductor 28a is in contact with the outer surface 71a of the first portion 71 and the inner surface 72b of the second portion 72. Thus, the conductor 28a is surrounded by the outer surface 71a of the first portion 71 and the inner surface 72b of the second portion 72. In this example, the inner surface 72b of the second portion 72 is bent toward the outer surface 71a of the first portion 71, thereby crimping the conductor 28a between the first portion 71 and the second portion 72.

[0034] FIG. 14 is a perspective view illustrating the process of connecting the terminal 70 and the conductor 28a to each other. For simplicity, FIG. 14 illustrates only a portion of the conductor 28a of the coil 28. As shown in FIG. 14 , an intermediate product 70A of the terminal 70 is prepared. In this intermediate product 70A, the second portion 72 is bent at a 90° angle relative to the first portion 71. That is, the inner surface 72b of the second portion 72 is bent at a 90° angle relative to the outer surface 71a of the first portion 71. The inner surface 72b is connected to the outer surface 71a. The outer surface 72a of the second portion 72 is bent at a 90° angle relative to the inner surface 71b of the first portion 71. This intermediate product 70A can be easily formed, for example, by punching or bending a metal plate. During the punching process, the groove 73 on the outer surface 71a of the first portion 71 is formed by half-punching.

[0035] Meanwhile, the conductor 28a of the coil 28 is not bent either. That is, the conductor 28a extends straight radially outward. In this state, the slit 74 of the terminal 70 can receive the conductor 28a. The conductor 28a is inserted up to its lower end within the slit 74. In this state, the upper ends 75, 75 of the first portion 71 are crimped so that they approach each other in the circumferential direction. In this manner, the conductor 28a is crimped by the upper ends 75, 75. Thereafter, the conductor 28a is bent from the inner end of the slit 74 toward the groove 73. In this state, the second portion 72 is bent along one end of the first portion 71 in the circumferential direction. As a result, the inner surface 72b of the second portion 72 crimps the conductor 28a between itself and the outer surface 71a of the first portion 71. In this manner, the terminal 70 and the conductor 28a are coupled.

[0036] FIG. 15 is a perspective view schematically illustrating the structure of a stator assembly 25B according to yet another example. This stator assembly 25B incorporates a busbar unit 40A according to another example instead of the busbar unit 40 described above. FIG. 16 is an exploded perspective view schematically illustrating the structure of the stator assembly 25B with the busbar unit 40A removed. Note that the same components as those in the stator assembly 25 are designated by the same reference numerals, and redundant description will be omitted. Referring to both FIGS. 15 and 16 , this stator assembly 25B includes, for example, an annular member (hereinafter referred to as the "annular member") 8 disposed between the busbar unit 40A and the plurality of coils 28. In this example, the annular member 8 is disposed on the plurality of coils 28.

[0037] The busbar unit 40A includes a plurality of outer terminals 46A that protrude radially outward from the housing 41, a plurality of inner terminals 49A that protrude radially inward from the housing 41, and a plurality of external terminals 47 similar to those described above. The outer terminals 46A and the inner terminals 49A each have a hole 46a that penetrates the outer terminal 46A and the inner terminal 49A parallel to the axis x. A conductor wire 28a of the coil 28 is inserted into the hole 46a and 49a and electrically connected to the hole 46a and the inner terminal 49A. The conductor wire 28a is electrically connected to the outer terminal 46A and the inner terminal 49A by, for example, welding, heat crimping, fusing, or the like.

[0038] The annular member 8 is formed of a material that has high thermal conductivity relative to the insulator 27. In one example, the material with high thermal conductivity is a resin material containing PPS (polyphenylene sulfide). The annular member 8 has a main body 81 formed of an annular flat plate and multiple portions (hereinafter referred to as "guide portions") 82 formed on the main body 81 to guide portions of the conductor wire 28a of the coil 28. In this example, the guide portions 82 have multiple outer portions (hereinafter referred to as "outer portions") 83 arranged on the outer periphery of the main body 81 and multiple inner portions (hereinafter referred to as "inner portions") 84 arranged on the inner periphery of the main body 81.

[0039] In this example, twelve outer members 83 are formed on the main body 81 to correspond to the twelve conductors 28a drawn from the outer periphery of the coil 28. Similarly, twelve inner members 84 are formed on the main body 81 to correspond to the twelve conductors 28a drawn from the inner periphery of the coil 28. Each of the outer members 83 guides a portion of the conductors 28a drawn from the outer periphery of the coil 28 upward in the direction of the rotation axis. The inner members 84 guide a portion of the conductors 28a drawn from the inner periphery of the coil 28 upward in the direction of the rotation axis. The guide portions 82, i.e., the outer members 83 and inner members 84, are formed integrally with the main body 81.

[0040] FIG. 17 is an exploded perspective view schematically illustrating the structure of a busbar unit 40A according to another specific example. The housing 41 of the busbar unit 40A includes a base 41a that houses a busbar group 42 and a cover 41b that covers the upper end of the base 41a. Both the base 41a and the cover 41b are formed of a resin material. The resin material is, for example, an insulating material. In this example, the busbar group 42 includes three first busbars 43B and six second busbars 44B. The three first busbars 43B are stacked in the rotational axis direction. The six second busbars 44B are arranged in the circumferential direction. An outer terminal 46A and an external terminal 47 are formed on the first busbars 43B, while an inner terminal 49A is formed on the second busbars 44B.

[0041] All three first bus bars 43B have the same shape. Each first bus bar 43B has a first portion 43a extending in an arc in the circumferential direction and a second portion 43b circumferentially offset from the first portion 43a and extending in an arc in the circumferential direction. The first portion 43a and the second portion 43b are disposed at different heights in the axial direction. The first portion 43a and the second portion 43b are connected to each other by a step portion 43c. In this example, the first portion 43a is disposed lower than the second portion 43b in the rotational axis direction. Two external terminals 46A protrude outward from each of the outer peripheral portions 43d, which include the outer peripheral surfaces of the first portion 43a and the second portion 43b. In this example, one external terminal 47 extends upward after protruding outward from the outer peripheral portion 43d of the first portion 43b.

[0042] The second portion 43b of one of the first bus bars 43B, which is circumferentially adjacent to the first bus bar 43B, overlaps the first portion 43a of the other first bus bar 43B. When the first bus bars 43B are overlapped in this manner in the rotational axis direction, the twelve outer terminals 46A are arranged at predetermined intervals around the axis x. Similarly, the three external terminals 45 are arranged at predetermined intervals around the axis x. An insulating member 43e is disposed between the first portion 43a and the second portion 43b that are overlapped in the rotational axis direction. The insulating member 43e is, for example, an insulating sheet. The presence of this insulating member 43e electrically insulates the first bus bars 43B, 43B that are adjacent in the rotational axis direction.

[0043] All of the second bus bars 44B have the same shape. The second bus bars 44B are arranged more inward than the first bus bars 43B. The second bus bars 44B are spaced apart in the circumferential direction at predetermined intervals. Each second bus bar 44B has a wall portion 44a extending in the circumferential direction. The wall portion 44a is arc-shaped in a plan view in the rotation axis direction. The wall portion 44a faces the first bus bar 43B in the radial direction. In this example, the height of the wall portion 44a in the axial direction is set to a size that roughly matches the height of the first bus bars 43B stacked in the axial direction. Two inner terminals 49A protrude inward from the upper end of an inner peripheral portion 44b, which includes the inner peripheral surface of the wall portion 44a.

[0044] The base 41a of the housing 41 defines an annular space that houses the bus bar group 42. Specifically, the base 41a has a first space S1 disposed on the outer periphery and housing three first bus bars 43B, and a second space S2 disposed on the inner periphery of the first space S1 and housing six second bus bars 44B. The first space S1 is defined by a side wall 41c on the outer periphery of the base 41a and a partition wall 41d that separates the first space S1 from the second space S2. The second space S2 is defined by a side wall 41e on the inner periphery of the base 41a and the partition wall 41d. When the cover 41b is placed on the base 41a, the first space S1 and the second space S2 within the base 41a are closed by the cover 41b.

[0045] A plurality of recesses 41f are formed in the outer peripheral sidewall 41c. Each recess 41f is formed from the upper end to the lower end of the outer peripheral sidewall 41c. When three circumferentially arranged first bus bars 43B are housed in the first space S1, an outer terminal 46A is disposed in each recess 41f. On the other hand, a plurality of recesses 41g are formed in the inner peripheral sidewall 41e. Each recess 41f is formed from the upper end to the lower end of the inner peripheral sidewall 41e. When six circumferentially arranged second bus bars 44B are housed in the second space S2, an inner terminal 49A is disposed in each recess 41g. In this example, the recesses 41f and 41g are formed to the same depth from the upper end to the lower end of the sidewalls 41c and 41e, respectively.

[0046] FIG. 18 is a partially enlarged perspective view schematically illustrating the structure of the stator assembly 25B. The busbar unit 40A is not illustrated in FIG. 18 . FIGS. 19 and 20 are perspective views schematically illustrating the structure of an annular member 8 according to a specific example. FIG. 19 is a perspective view of the annular member 8 as viewed from above in the rotational axis direction, and FIG. 20 is a perspective view of the annular member 8 as viewed from below in the rotational axis direction. Note that the annular member 8 shown in FIG. 18 has been heat-welded to bond the conductor wires 28 a of the coils 28 to the annular member 8. On the other hand, the annular member 8 shown in FIGS. 19 and 20 is in a state before the conductor wires 28 a of the coils 28 have been bonded, and the annular member 8 has not been heat-welded to bond the conductor wires 28 a of the coils 28.

[0047] 18 to 20 , a convex portion 85 extending in the circumferential direction is formed on the upper surface of the main body 81. In this example, the convex portion 85 is formed in a ring shape and extends continuously in the circumferential direction. An outer portion 83 and an inner portion 84 formed on the main body 81 are separated from each other by the convex portion 85. The convex portion 85 is integrally formed with the main body 81. The outer portions 83 are arranged at predetermined intervals (approximately equal intervals in this example) in the circumferential direction along the outer peripheral edge of the main body 81. The inner portions 84 are arranged at predetermined intervals (approximately equal intervals in this example) in the circumferential direction along the inner peripheral edge of the main body 81. In this example, the outer portions 83 and the inner portions 84 corresponding to the outer portions 83 are arranged in the radial direction. In the state shown in FIG. 15 , the base 41a of the busbar unit 40A is supported on the convex portion 85 at its bottom surface.

[0048] In one example, each of the outer and inner portions 83 and 84 is formed into a cylindrical shape defined along an axis parallel to the axis x. Each of the outer and inner portions 83 and 84 defines a through-hole extending through the main body 81 parallel to the axis x. On the upper surface side of the main body 81, each of the outer portions 83 has a pair of first wall portions 83 a, 83 a facing each other in the radial direction and a pair of second wall portions 83 b, 83 b facing each other in the circumferential direction between the pair of first wall portions 83 a, 83 a. Thus, the pair of first wall portions 83 a, 83 a and the pair of second wall portions 83 b, 83 b form a cylindrical portion centered on an axis parallel to the axis x. In the state shown in FIGS. 19 and 20 , the first wall portion 83 a and the second wall portion 83 b adjacent to each other around the axis parallel to the axis x face each other across a gap.

[0049] Similarly, each inner portion 84 includes, on the upper surface of the main body 81, first walls 84a, 84a corresponding to the first walls 83a, 83a, and second walls 84b, 84b corresponding to the second walls 83b, 83b. The pair of first walls 84a, 84a and the pair of second walls 84b, 84b form a cylindrical portion centered on an axis parallel to the axis x. In the states shown in FIGS. 19 and 20 , the first wall 84a and the second wall 84b adjacent to each other about the axis parallel to the axis x face each other across a gap. The height of each outer portion 83 and each inner portion 84 defined above the top surface of the main body 81 is set to be greater than the height of the protrusion 85 defined above the same top surface. In the state shown in FIG. 15 , the housing 41 of the busbar unit 40A is disposed between the outer portions 83 and the inner portions 84.

[0050] As shown in Figure 20, on the underside of the main body 81, each of the outer portions 83 and inner portions 84 stands upright in a cylindrical shape at a predetermined height downward from the underside of the main body 81. A pair of corresponding outer portions 83 and inner portions 84 arranged radially are connected to each other by a rib 86 extending radially from the outer portion 83 to the outer portion 84. The rib 86 is integrally formed with the underside of the main body 81 and with the outer portion 83 and inner portion 84. In this example, the rib 86 has a triangular shape tapering downward from the underside of the main body 81 in a cross section taken along a plane perpendicular to the radial direction. Such a rib 86 can reinforce the strength of the main body 81, i.e., the annular member 8.

[0051] As can be seen from Figure 18, each outer portion 83 and inner portion 84 and each corresponding rib 86 are disposed between a pair of circumferentially adjacent coils 28, 28. The conductive wire 28a of the coil 28 is wound around the spoke 31 via the insulator 27 around a winding axis defined in the radial direction, so that a roughly triangular prism-shaped space having an axis in the radial direction is formed on the upper end side of each circumferentially adjacent coil 28, 28. Therefore, the triangular cross-sectional shape of the rib 86 does not prevent the rib 86 from being disposed on the coils 28, 28. The rib 86 can also serve to position the annular member 8 with respect to the multiple coils 28.

[0052] 19 and 20 , the height of each outer portion 83 and each inner portion 84 from the bottom surface of the main body 81 is set to be greater than the height from the top surface of the main body 81 in the rotational axis direction. As shown in FIG. 18 , each outer portion 83 and each inner portion 84 can be disposed between a pair of circumferentially adjacent coils 28, 28, and therefore may have a certain degree of height from the bottom surface of the main body 81. However, because the busbar unit 40A is disposed on the top surface of the main body 81, it is preferable to reduce the height of each outer portion 83 and each inner portion 84 from the top surface of the main body 81. By reducing the height of each outer portion 83 and each inner portion 84 from the top surface of the main body 81, it is possible to reduce the increase in the size of the motor 1 itself in the rotational axis direction.

[0053] As shown in Figure 20, on the underside of the main body 81, guide surfaces 87, 88 that taper upward in the rotational axis direction are formed on the inner circumferential surfaces adjacent to the lower ends of the outer portions 83 and the inner portions 84. The guide surfaces 87, 88 are defined by truncated cone surfaces whose central axes coincide with the axes of the outer portions 83 and the inner portions 84. As will be described later, when the annular member 8 is placed on the multiple coils 28 during assembly of the stator assembly 25B, the conductor wires 28a are inserted into the outer portions 83 from the lower end, and the conductor wires 28a are inserted into the inner portions 84 from the lower end. At this time, the guide surfaces 87, 88 function as guides when inserting the tips of the conductor wires 28a into the outer portions 83 and the inner portions 84 from the lower ends thereof.

[0054] FIG. 21 is a partially enlarged perspective view showing how the coil 28 and the annular member 8 are connected. The busbar unit 40A is not shown in FIG. 21 . As described above, the conductor 28a of the coil 28 is pulled out upward from the coil 28. The conductor 28a is held within the outer portion 83 and the inner portion 84, respectively. In the outer portion 83, first walls 83a and second walls 83b surround the conductor 28a pulled out from the outer periphery of the coil 28. The second walls 83b are bonded to the outer periphery of the conductor 28a by being pressed against the conductor 28a through, for example, melting by heat welding. The second walls 83b may also be connected to the first walls 83a by heat welding.

[0055] Similarly, in the inner portion 84, the first walls 84a and the second walls 84b surround the conductive wires 28a drawn from the inner periphery of the coils 28. The second walls 84b are adhered to the outer periphery of the conductive wires 28a by being pressed against the conductive wires 28a, for example, by melting the second walls 84b through heat welding. The second walls 84b may also be joined to the first walls 84a through heat welding. In this way, all of the conductive wires 28a drawn upward from the multiple coils 28 are held in the outer portion 83 and the inner portion 84 of the annular member 8. In other words, the annular member 8 is held to the multiple coils 28 by being joined to the conductive wires 28a.

[0056] When assembling the stator assembly 25B, the conductor wires 28a of the coils 28 are wound around all of the spokes 31 of the stator core 26 via the insulators 27. All of the conductor wires 28a are drawn upward. The drawn conductor wires 28a are bonded to the outer portion 83 and the inner portion 84 of the annular member 8 by, for example, heat welding. All of the conductor wires 28a extend upward from the outer portion 83 and the inner portion 84. Then, the busbar unit 40A is placed on the annular member 8. At this time, the annular member 8 positions the tips of all of the conductor wires 28a in predetermined positions, facilitating the positioning of the conductor wires 28a relative to the holes 46a, 49a of the outer terminal 46A and the inner terminal 49A, respectively. This facilitates the process of connecting the conductor wires 28a to the outer terminal 46A and the inner terminal 49A.

[0057] 22 is a perspective view schematically illustrating the structure of a stator assembly 25C according to yet another example. This stator assembly 25C incorporates an annular member 9 instead of the aforementioned annular member 8. Other components similar to those of the aforementioned stator assembly 25B are designated by the same reference numerals, and redundant description will be omitted here. This annular member 9 is formed in an annular shape around the axis x and is disposed between the multiple coils 28 and the busbar unit 40A in the rotational axis direction. Similar to the annular member 8, the conductor wires 28a extending from the multiple coils 28 are bonded to the annular member 9. Thus, the annular member 9 holds all the conductor wires 28a extending from the multiple coils 28.

[0058] FIG. 23 is a partially enlarged perspective view schematically illustrating the structure of a stator assembly 25C. The busbar unit 40A is not illustrated in FIG. 23 . FIGS. 24 and 25 are perspective views schematically illustrating the structure of an annular member 9 according to a specific example. FIG. 24 is a perspective view of the annular member 9 as viewed from above in the rotational axis direction, and FIG. 25 is a perspective view of the annular member 9 as viewed from below in the rotational axis direction. Referring to FIGS. 23 to 25 together, the annular member 9 has a main body 91 formed of an annular flat plate, and a plurality of portions (hereinafter referred to as "guide portions") 92 formed on the main body 91 to guide portions of the conductor wire 28a of the coil 28.

[0059] In this example, the guide portion 92 has a plurality of outer portions (hereinafter referred to as "outer portions") 93 arranged on the outer periphery side of the main body 91, and a plurality of inner portions (hereinafter referred to as "inner portions") 94 arranged on the inner periphery side of the main body 91. Each of the outer portions 93 guides a portion of the conductor 28a drawn upward in the direction of the rotation axis from the outer periphery side of the coil 28. Each of the inner portions 94 guides a portion of the conductor 28a drawn upward in the direction of the rotation axis from the inner periphery side of the coil 28. The guide portion 92 is formed integrally with the main body 91.

[0060] The upper surface of the main body 91 is formed with circumferentially extending convex portions 95, similar to the convex portions 85 of the annular member 8 described above. The outer portion 93 and the inner portion 94 are separated from each other by the convex portions 95. The outer portions 93 are arranged at predetermined intervals (approximately equal intervals in this example) in the circumferential direction along the outer peripheral edge of the main body 91. The inner portions 94 are arranged at predetermined intervals (approximately equal intervals in this example) in the circumferential direction along the inner peripheral edge of the main body 91. In this example, the outer portions 93 and the corresponding inner portions 94 are arranged radially. In the state shown in FIG. 23 , the base 41a of the busbar unit 40A is supported on the convex portions 95 at its bottom surface.

[0061] Figure 26 is a partially enlarged plan view schematically showing the structure of one of the outer portion 93 and inner portion 94, and Figure 27 is a partially enlarged bottom view schematically showing the structure of one of the outer portion 93 and inner portion 94. Referring to Figures 24 to 27 together, the multiple guide portions 92, i.e., the multiple outer portions 93 and the multiple inner portions 94, have multiple holes, i.e., multiple slits 96, 97, penetrating the main body 91 in the rotation axis direction, and multiple pairs of wall portions 98, 99 formed in the main body 91 adjacent to the slits 96, 97. Since the outer portion 93 and the inner portion 94 have similar shapes, the outer portion 93 will be described below.

[0062] The slit 96 is formed into a shape whose longitudinal direction is the circumferential direction as a whole. The slit 96 has a first portion 96a that tapers from one side to the other in the circumferential direction and a second portion 96b that is connected to the other end of the first portion 96a. In this example, in a plan view in the rotation axis direction, the first portion 96a has, for example, a generally drop shape. The second portion 96b has, for example, a circular shape. The second portion 96b has approximately the same dimensions as the other end of the first portion 96a. The radial dimension of the second portion 96b is set to be approximately the same as the diameter of the conductor 28a of the coil 28. The conductor 28a is held within the second portion 96b.

[0063] As shown in FIG. 27 , a pair of protrusions 96c, 96c are formed between the first portion 96a and the second portion 96b, protruding toward each other in a generally radial direction. These pair of protrusions 96c, 96c contact the outer peripheral surface of the conductor 28a, thereby holding the conductor 28a within the second portion 96b. Also, as shown in FIG. 26 , a pair of wall portions 98, 98 are formed on the upper surface of the main body 91 to surround the second portion 96b of the slit 96. The pair of wall portions 98, 98 are opposed to each other in the radial direction. Each wall portion 98 has a curved shape that follows the circular outline of the second portion 96b. The pair of wall portions 98, 98 are bonded to the conductor 28a of the coil 28 by melting through heat welding.

[0064] The slit 97 of the inner portion 94 has a first portion 97a, a second portion 97b, and a pair of protrusions 97c, 97c similar to the slit 96, which has a first portion 96a, a second portion 96b, and a pair of protrusions 96c, 96c. However, the shape of the slit 97 of the inner portion 94 in a plan view is approximately symmetrical with respect to a plane perpendicular to the radial direction. Similarly, the length of the slit 97 in the circumferential direction is set to be shorter than the length of the slit 96 in the circumferential direction. Furthermore, the pair of wall portions 99, 99 of the inner portion 94 are configured similarly to the pair of wall portions 98, 98 of the outer portion 93.

[0065] When assembling the stator assembly 25C as described above, all of the plurality of conductors 28a drawn out upward are disposed within the first portions 96a and 97a of the slits 96 and 97 in the outer and inner portions 93 and 94 of the annular member 9, respectively, as shown in FIG. 28 . In this state, by rotating the annular member 9 around the axis x in the direction of arrow A (counterclockwise in this example), the conductors 28a are guided toward the second portions 96b and 97b along the contours of the first portions 96a and 97a. At this time, the conductors 28a are held within the second portions 96b and 97b by the pair of protrusions 96c and the pair of protrusions 97c. In this way, the position of the annular member 9 is fixed relative to the plurality of coils 28.

[0066] In this state, the walls 98, 99 of the annular member 9 are heat-welded, for example, to adhere the walls 98, 99 to the conductors 28a. All of the conductors 28a extend upward from the outer portion 93 and the inner portion 94. The busbar unit 40A is then placed on the annular member 9. At this time, all of the conductors 28a are positioned in predetermined positions by the annular member 9, which facilitates the positioning of the conductors 28a relative to the holes 46a, 49a of the outer terminal 46A and the inner terminal 49A of the busbar unit 40A. This facilitates the connection of the conductors 28a to the outer terminal 46A and the inner terminal 49A.

[0067] FIG. 29 is a perspective view schematically illustrating the structure of a modified annular member 9A. This annular member 9A is a modified version of the annular member 9 described above. In the annular member 9A, the protrusions 95 formed on the main body 91 are omitted. Instead, the main body 91 has multiple lightening holes 91a formed between multiple outer portions 93 and multiple inner portions 94. Each lightening hole 91a penetrates the main body 91 in the rotational axis direction. In this example, the lightening holes 91a are circular in plan view and are arranged at predetermined intervals in the circumferential direction. Other components similar to those of the previously described annular member 9 are denoted by the same reference numerals, and redundant description will be omitted here. The lightening holes 91a enable the annular member 9A to be lightweight.

[0068] Fig. 30 is a partially enlarged perspective view schematically illustrating the structure of an outer terminal 46B according to a modified example, and Fig. 31 is a partially enlarged plan view schematically illustrating the structure of the outer terminal 46B according to the modified example. Figs. 30 and 31 show one outer terminal 46B disposed in a recess 41f formed in the outer peripheral sidewall 41c of the base 41a of the busbar unit 40A. The cover 41b and other busbars 43B, 44B, etc. are omitted from the illustration. The outer terminal 46B is shown in a state in which the conductor 28a of the coil 28 is not connected. The inner terminal 49A may also be configured similarly to the outer terminal 46B.

[0069] The outer terminal 46B has a slit 46b extending from the outer peripheral end of the outer terminal 46B to the hole 46a. The circumferential dimension of the slit 46b is similarly set smaller than the circumferential dimension of the hole 46a. The outer terminal 46B has a pair of side portions 46c, 46c facing each other in the circumferential direction, each of which has a recess 46d formed in the outer peripheral portion 43d of the outer terminal 46B. The recess 46d is recessed in the circumferential direction from the side portion 46c into the outer terminal 46B. The recess 46d is positioned corresponding to the side wall 41c of the base 41a. As a result, when the outer terminal 46B is placed in the recess 41f of the side wall 41c, the end of the side wall 41c of the base 41a fits into the recess 46d of the outer terminal 46B.

[0070] FIG. 32 is a partially enlarged plan view illustrating the electrical connection of the conductor 28a to the outer terminal 46B. The conductor 28a is inserted into the hole 46a of the outer terminal 46B. The electrodes 2A and 2B used for heat crimping or fusing contact the side portions 46c and 46c of the outer terminal 46B, respectively. At this time, the electrodes 2A and 2B are pressed against the side portions 46c and 46c of the outer terminal 46B with a predetermined pressure, respectively, in a direction approaching each other in the circumferential direction. Resistance heating generated by the electrodes 2A and 2B when a current flows through the outer terminal 46B is used to join the outer terminal 46B and the conductor 28a. Furthermore, the pressure from the electrodes 2A and 2B causes the slit 46b of the outer terminal 46B to deform in a narrowing direction, thereby holding the conductor 28a.

[0071] Resistive heat generated in the outer terminal 46B transfers heat from the outer terminal 46B to the base 41a, for example, at a temperature higher than the melting point of the base 41a. As a result, the resin material of the base 41a is welded to the recess 46d in the side portion 46c of the outer terminal 46B. In this way, for example, the first bus bar 43B is adhered and fixed to the base 41a. With this configuration, the first bus bar 43B is firmly fixed to the base 41a. Therefore, rattle due to vibration of the first bus bar 43b is suppressed despite rotation of the rotor 24. As a result, noise generation from the bus bar unit 40B can be suppressed, and, for example, disconnection between the outer terminal 46B and the conductor 28a can be prevented.

[0072] FIG. 33 is a partially enlarged plan view schematically illustrating the structure of a modified outer terminal 46B. FIG. 33 illustrates a state in which the conductor 28a is electrically connected to the outer terminal 46B. This outer terminal 46B has recesses 46e, 46e formed on the side portions 46c, 46c of the aforementioned outer terminal 46B. Each recess 46e is recessed from the side portion 46c into the outer terminal 46B. The recess 46e is located on the outer periphery side of the recess 46d. Similarly, the depth of the recess 46e in the circumferential direction is set to be greater than the depth of the recess 46d in the circumferential direction. In this example, the depth of each recess 46e is approximately one-third the circumferential dimension of the outer terminal 46B.

[0073] With this outer terminal 46B, when a pair of electrodes is pressed against the side portions 46c of the metal terminal 46B with a predetermined pressure during fusing, the pair of recesses 46e allows the outer terminal 46B to deform more significantly in the area surrounding the recesses 46e, i.e., the area that holds the conductor 28a. As a result, the outer terminal 46B can more firmly hold the conductor 28a. Furthermore, the pair of recesses 46e suppresses heat loss from the recesses 46e toward the inner periphery, allowing the outer periphery of the outer terminal 46B to be heated in a short time. As a result, the set voltage (current) for fusing can be reduced. The inner terminal 49A may also be configured similarly to the outer terminal 46B.

[0074] 34 to 37 are partially enlarged perspective views schematically illustrating the structure of a modified outer terminal 46A. In FIG. 34, an annular weld 46f is formed on the upper surface of the outer terminal 46A by welding the outer terminal 46A to the conductor 28a. In this manner, the outer terminal 46A and the conductor 28a may be electrically connected. In FIG. 35, a tapered surface 46g is formed on the lower end of the hole 46a of the outer terminal 46A. The tapered surface 46g tapers upward from the lower end of the hole 46a. The tapered surface 46g can guide the insertion of the conductor 28a into the hole 46a. This tapered surface 46g may also be formed on the hole 49a formed in, for example, the inner terminal 49A.

[0075] In FIG. 36 , protrusions 46h, 46h that protrude in opposite directions in the circumferential direction may be formed on opposing side portions 46c, 46c of the outer terminal 46A. In this example, the protrusions 46h are semicircular in plan view in the axial direction. The protrusions 46h are formed in an area of ​​the side portions 46c that at least partially overlaps the hole 46a in the circumferential direction. With these protrusions 46h, 46h, when the outer terminal 46A is clamped by a pair of electrodes with a predetermined pressure during fusing, the protrusions 46h bite into the outer terminal 46A, thereby more firmly holding the conductor 28a in the hole 46a. This configuration may also be applied to the inner terminal 49A.

[0076] In FIG. 37, the opposing side portions 46c, 46c of the outer terminal 46A and the outer peripheral end portion of the outer terminal 46A may be crimped toward the inside of the outer terminal 46A. This crimping creates a recess in the side portion 46c and end portion of the outer terminal 46A that recesses toward the inside of the outer terminal 46A. The inner peripheral surface of the hole 46a can be pressed toward the conductor 28a in accordance with the position of this recess. This allows the outer terminal 46A to more firmly hold the conductor 28a. The examples shown in FIGS. 34 to 37 may be applied in combination with one another.

[0077] FIG. 38 is a partially enlarged perspective view schematically illustrating a modified structure of the outer terminal 46B. In this example, protrusions 46j, 46j protruding in opposite circumferential directions may be formed on opposing side portions 46c, 46c of the outer terminal 46B. In this example, the protrusions 46j are rectangular in plan view in the rotational axis direction. The protrusions 46j are formed adjacent to the outer peripheral end of the side portion 46c. With these protrusions 46j, 46j, when the outer terminal 46B is clamped between a pair of electrodes with a predetermined pressure during fusing, the protrusions 46j bite into the outer terminal 46B, thereby more firmly holding the conductor 28a in the hole 46a. The configurations shown in FIGS. 34 to 38 may also be applied to the inner terminal 49A.

[0078] FIG. 39 is a partially enlarged perspective cross-sectional view schematically illustrating the structure of a motor 1 according to another embodiment of the present invention, and FIG. 40 is a partially enlarged cross-sectional view schematically illustrating the structure of a motor 1 according to another embodiment of the present invention. Referring to both FIG. 39 and FIG. 40 , in this motor 1, the cover 41b of the housing 41 of the busbar unit 40A has a flange 41h that extends further inward than the inner end of the base 41a. In this example, the flange 41h is formed in an annular shape around the axis x. The flange 41h is disposed between the tip of the conductor 28a of the coil 28 and the housing main body 14 of the housing 11 of the motor 1. Other components similar to those described above are designated by the same reference numerals, and redundant description will be omitted here.

[0079] According to this configuration, the flange 41h of the cover 41b, which is made of an insulating material including, for example, a resin material, is disposed between the tip of the conductor 28a and the housing main body 14, which is made of a conductive metal material. As a result, conduction, i.e., a short circuit, due to contact between the conductor 28a and the housing main body 14 can be prevented. In this example, as is clear from Figures 39 and 40, the tip of the conductor 28a contacts the underside of the flange 41h. However, the tip of the conductor 28a may face the underside of the flange 41h with a predetermined gap therebetween. The flange 41h may also extend outward from the outer peripheral end of the cover 41b.

[0080] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the scope of the present invention. Furthermore, the above-described embodiments do not limit the scope of the present invention, and the present invention may include any and all applications. The components of the above-described embodiments, as well as their arrangement, materials, conditions, shape, size, etc., are not limited to those illustrated and may be modified as appropriate. For example, the present invention includes differences that arise during implementation due to manufacturing tolerances, etc. Furthermore, components illustrated in different embodiments may be partially substituted or combined within the scope of technical inconsistency. Furthermore, the various configurations may be selectively combined as appropriate to achieve at least some of the above-described problems and effects.

[0081] REFERENCE SIGNS LIST 1 Motor, 10 Shaft, 11 Housing, 12, 13 Bearing, 14 Main body (housing main body), 14a Flange, 15 Cover, 16 Opening, 17 Opening, 18 Rotor core, 19 Inner peripheral portion, 20 Outer peripheral portion, 21 Connection portion, 22 Magnet, 23 Through hole, 24 Rotor, 25, 25A, 25B, 25C Stator assembly, 26 Stator core, 27 Insulator, 27a Recess, 28 Coil, 28a Conductor, 29 Cylindrical portion, 30 Teeth, 31 Spoke, 32 Magnetic pole portion, 33 Stator, 40, 40A, 40B Busbar unit, 41 Housing, 41a Base, 41b Cover, 41c Side wall, 41d Partition wall, 41e Side wall, 41f Recess, 41g Recess, 41h Flange, 42 Bus bar group, 43, 43B first bus bar, 43a first portion, 43b first portion, 43c step portion, 43d outer periphery portion, 43e insulating member, 43A intermediate product, 44, 44B second bus bar, 44a wall portion, 44b inner periphery portion, 45 annular portion (annular portion), 46, 46A, 46B terminal (outer terminal, metal member), 46a hole portion, 46b slit, 46c side portion, 46d recess, 46e recess, 46f welded portion, 46g tapered surface, 46h protrusion, 46i protrusion, 46j protrusion, 47 terminal (external terminal), 48 main body, 49, 49A terminal (inner terminal, metal member), 50 first portion, 50a upper surface (first surface), 50b lower surface, 51 second portion, 51a upper surface, 51b Lower surface (second surface), 52 Groove, 53 Slit, 54 Portion (outer end), 60 Connecting plate, 61 Main body, 62 Hole portion, 70 Terminal (metal member), 70A Intermediate product, 71 First portion, 71a Outer surface (first surface), 71b Inner surface, 72 Second portion, 72a Outer surface, 72b Inner surface (second surface), 73 Groove, 74 Slit, 75 Portion (upper end), 8 Annular member (Annular member), 81 Main body, 82 Guide portion, 83 Outer portion, 84 Inner portion, 85 Convex portion, 86 Rib, 87 Guide surface, 9 Annular member (Annular member), 91 Main body, 91a Lightening portion, 92 Guide portion, 93 Outer portion, 94 Inner portion, 95 Convex portion, 95a First portion, 95b Second portion, 95c Protrusion, 96 Slit, 96a First portion, 96b: Second portion, 96c: Protrusion, 97: Slit, 97a: First portion, 97b: Second portion, 97c: Protrusion, 98, 99: Wall portion,x axis,

Claims

1. A motor comprising: a conducting wire forming a coil; and a metal member having a first surface in contact with the conducting wire and a second surface overlapping the first surface, wherein the conducting wire is fitted into a groove formed in the first surface, and the conducting wire is surrounded and crimped by the first surface and the second surface.

2. The motor according to claim 1, wherein a slit connected to said groove is formed in said first surface.

3. The motor according to claim 1 or 2, wherein the second surface is connected to the first surface.

4. The motor according to claim 3, wherein the metal member comprises a first portion having the one surface and a second portion having the second surface, and the second portion is connected to the first portion in a manner that allows it to be bent.

5. The motor according to claim 4, wherein the first direction in which said first portion extends and the second direction in which said second portion extends are directions that intersect with each other.

6. The motor according to claim 5, wherein the bent conductor wire is fitted into the groove.

7. A motor comprising: a plurality of conducting wires forming a plurality of coils; a plurality of bus bars electrically connected to the plurality of coils in the direction of the rotation axis; and a member having a plurality of portions for guiding portions of the plurality of conducting wires between the plurality of coils and the plurality of bus bars in the direction of the rotation axis, the plurality of portions of the member being adhered to portions of the plurality of conducting wires.

8. The motor according to claim 7, comprising a stator having a magnetic body, an insulator, and the plurality of coils wound around the insulator, wherein the member has high thermal conductivity with respect to the insulator.

9. The motor according to claim 7 or 8, wherein the plurality of bus bars comprise an inner periphery having a plurality of inner terminals and an outer periphery having a plurality of outer terminals, and the member comprises a plurality of portions of the member having a plurality of inner portions that guide the conductors electrically connected to the plurality of inner terminals and a plurality of outer portions that guide the conductors electrically connected to the plurality of outer terminals, and a plurality of ribs extending from the plurality of inner portions to the plurality of outer portions.

10. The motor according to claim 9, wherein the plurality of ribs are arranged between the plurality of coils in the circumferential direction.

11. The motor according to claim 9 or 10, wherein the plurality of portions of the member are a plurality of holes or a plurality of slits with the circumferential direction as the longitudinal direction.

12. A motor according to any one of claims 9 to 11, comprising a base formed of a resin member that houses a plurality of bus bars, the base comprising an outer peripheral side wall having a plurality of recesses and an inner peripheral side wall having a plurality of recesses, outer terminals of the bus bars are arranged in the recesses of the outer peripheral side wall, and the resin member that forms the recesses of the outer peripheral side wall is adhered to the outer terminals.

13. A motor according to any one of claims 9 to 12, wherein an inner terminal of the bus bar is disposed in the recess in the inner peripheral side wall, and the resin member forming the recess in the inner peripheral side wall is adhered to the inner terminal.

14. A motor according to any one of claims 9 to 13, wherein a side portion of the outer terminal has a recess in the circumferential direction, and a part of the resin member is adhered to the recess in the side portion of the outer terminal.

15. A motor according to any one of claims 9 to 13, wherein a side portion of the inner terminal has a recess in the circumferential direction, and a part of the resin member is adhered to the recess in the side portion of the inner terminal.

16. A motor according to any one of claims 9 to 13, wherein a recess is formed in a portion of the inner terminal on the inner periphery side or a portion of the outer terminal on the outer periphery side.

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