Motor

Abstract

Motor (10) which has the following features: a rotor (30) with a shaft (31) having a central axis (J) extending in a vertical direction, as its center; a stator (40) arranged radially outside the rotor (30); a bearing located on the top side of the stator to support the shaft in a rotatable manner; a tubular housing (20) arranged to hold the stator (40); a bearing support (50) arranged on the top of the stator to hold the bearing; and a busbar unit (60) arranged on a top side of the bearing support to supply an electrical drive current to the stator; wherein: the rotor (30) has a rotor magnet (33) which is fixed directly or indirectly to the shaft; the stator (40) has the following features: a ring-shaped nucleus back (41a); Teeth (41b) arranged so that they extend radially inward from the nucleus dorsum; and Coils (43) wound around the teeth; the housing (20) has an inner circumferential surface (21a) arranged to hold the stator (40); the bearing holder (50) is arranged in contact with the inner circumferential surface (21a) of the housing; and the busbar unit (60) is arranged in contact with the inner circumferential surface of the housing (21a); wherein the busbar unit (60) has the following features: at least one busbar (90) which is electrically connected to the stator (40); and a busbar support arranged to hold at least one busbar; and the busbar support has the following features: a mounting body section; and a plurality of touch sections (65), each arranged in such a way that that they protrude downwards from the mounting body section; the majority of the impact sections (65) are arranged at regular intervals along a circumferential direction; and a lower surface of each bump section (65) is arranged such that it is in contact with an upper surface of the bearing support; wherein each of the at least one busbar (90) has the following features: a busbar section; and a busbar connection section (92) arranged so that it projects upwards from the busbar body section; and wherein each bump section (65) is arranged at the same circumferential position as that of the corresponding busbar connection section.

Description

[0001] The present invention relates to a motor.

[0002] Some well-known motors incorporate a busbar assembly. The busbar assembly is attached, for example, to a stator core.

[0003] Motors are also disclosed in the prior art documented in patent literature. For example, JP 2014-75 866 A discloses an electric power steering device with a motor and a control unit. JP 2013-188 040 A also relates to a motor for an electric power steering system. Furthermore, reference should also be made to DE 11 2008 001 262 T5 and WO 2014 / 112 301 A1, both of which disclose electric motors.

[0004] Some other known motors include a busbar assembly, a bearing bracket, and a stator arranged axially in the aforementioned order. In such a motor, the bearing bracket is located between the busbar assembly and the stator. Consequently, it is impossible to attach the busbar assembly to a stator core to position it relative to the stator. Therefore, it is difficult to position the busbar assembly with high accuracy relative to the stator, which can lead to a reduction in the accuracy with which the busbar assembly is positioned relative to the stator.

[0005] The object of the present invention is to create a motor with improved characteristics.

[0006] This problem is solved by a motor according to claim 1.

[0007] A motor according to a preferred embodiment of the present invention comprises a rotor, a stator, a bearing, a housing, a bearing support, and a busbar assembly. The rotor includes a shaft with a central axis extending vertically. The stator is arranged radially outside the rotor. The bearing is arranged on a top surface of the stator to rotatably support the shaft. The housing is tubular and serves to hold the stator. The bearing support is located on the top surface of the stator to hold the bearing. The busbar assembly is arranged on a top surface of the bearing support to supply an electrical drive current to the stator. The rotor includes a rotor magnet, which is fixed directly or indirectly to the shaft. The stator includes an annular core back, teeth, and coils.The teeth are arranged to extend radially inward from the core back. The coils are wound around the teeth. The housing includes an inner circumferential surface designed to hold the stator. The bearing support is arranged to be in contact with the inner circumferential surface of the housing. The busbar assembly is also arranged to be in contact with the inner circumferential surface of the housing. Further features are defined by the independent claims.

[0008] The above and further elements, features, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments with reference to the accompanying drawings. These show: Fig. 1 a cross-sectional view of a motor according to a preferred embodiment of the present invention; Fig. 2 a top view of a bearing support according to a preferred embodiment of the present invention; Fig. 3 a cross-sectional view of a section of the motor according to a preferred embodiment of the present invention; Fig. 4 a top view of a busbar unit according to a preferred embodiment of the present invention; and Fig. 5 a bottom view of the busbar unit according to a preferred embodiment of the present invention.

[0009] Motors according to preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be noted that the scope of protection of the present invention is not limited to the preferred embodiments described below, but includes any modification thereof within the scope of protection of the basic technical concept of the present invention. Furthermore, it should be noted that scales, numbers, etc., of components or sections shown in the accompanying drawings may differ from those of actual components or sections for the sake of easier understanding.

[0010] The accompanying drawings appropriately show an xyz coordinate system as a three-dimensional orthogonal coordinate system. In the xyz coordinate system, a z-axis direction is assumed to be a direction parallel to a central axis J, which is located in Fig. Figure 1 shows that the x-axis direction is a direction perpendicular to the z-axis direction, and that this direction is in Fig. 1. A horizontal direction is assumed. A y-axis direction is assumed to be a direction perpendicular to both the x-axis and z-axis directions.

[0011] In the following description, a direction in which a central axis J extends (i.e., the z-axis direction) is assumed to be a vertical direction. A positive side (i.e., a +z-side) in the z-axis direction is referred to as a top, while a negative side (i.e., a -z-side) in the z-axis direction is referred to as a bottom. However, it should be noted that the above definitions of vertical direction and top and bottom are simply for the sake of convenience and are not intended to restrict actual relative positions or directions of different components or sections. Additionally, unless otherwise specified, the direction parallel to the central axis J (i.e.,the z-axis direction) is simply referred to as "axial direction" or "axial", radial directions centered on the central axis J are simply referred to as "radial direction" or "radial", and a circumferential direction around the central axis J (i.e. a θ. z -direction) is simply referred to as "circumferential direction" or "circumferential".

[0012] It is assumed that the phrase "extends in an axial direction," "extends axially," or the like, as used in the following description, includes not only an exact extension in the axial direction, but also an extension in a direction at an angle of less than 45 degrees to the axial direction. Furthermore, it is assumed that the phrase "extends in a radial direction," "extends radially," or the like, as used in the following description, includes not only an exact extension in a radial direction, or exactly radially, i.e., exactly in a direction or directions perpendicular to the axial direction, but also an extension in a direction or directions at an angle of less than 45 degrees to the radial direction or directions.

[0013] Fig. Figure 1 is a cross-sectional view of a motor 10 according to a preferred embodiment of the present invention. Fig. Figure 2 is a top view of an upper bearing bracket 50 of the motor 10. Fig. Figure 3 is a cross-sectional view of a section of the engine 10. Fig. Figure 4 is a top view of a busbar unit 60 of the motor 10. Fig. Figure 5 is a bottom view of busbar unit 60. It is noted that the term "top view," as used herein, refers to a view of a particular target object from above. It is also noted that the term "bottom view," as used herein, refers to a view of a particular target object from below.

[0014] Referring to Fig. The motor 10 comprises a housing 20, a connector section 25, a rotor 30, a sensor magnet 71, a stator 40, the upper bearing bracket 50, bearings, the busbar unit 60, and a control unit 70. The bearings include a lower bearing 81 and an upper bearing 82. In the motor 10, the busbar unit 60, the upper bearing bracket 50, and the stator 40 are arranged in the order stated, with the busbar unit 60 at the top and the stator 40 at the bottom.

[0015] The housing 20 is arranged to accommodate the rotor 30, the sensor magnet 71, the stator 40, the upper bearing support 50, the lower bearing 81, the upper bearing 82, the busbar unit 60, and the control unit 70. The housing 20 is tubular and is designed to hold the stator 40. In this preferred embodiment, the housing 20 is made of a metal. The housing 20 comprises a housing tube section 21, a housing base plate section 22, a lower bearing support section 24, and a housing top plate section 23.

[0016] The housing section 21 is tubular and is arranged to extend in a circumferential direction, surrounding the stator 40. In this preferred embodiment, the housing tube section 21 is cylindrical or substantially cylindrical and is centered on the central axis J. A housing inner circumferential surface 21a is an inner circumferential surface of the housing tube section 21. The stator 40 is held by the housing inner circumferential surface 21a. This means that the housing 20 includes the housing inner circumferential surface 21a, which is arranged to hold the stator 40. The housing inner circumferential surface 21a is also an inner circumferential surface of the housing 20.

[0017] The housing base plate section 22 is connected to a lower end section of the housing tube section 21. The housing base plate section 22 is arranged to cover one underside of the stator 40. The housing base plate section 22 includes an output shaft hole 22a, which is arranged to extend axially through the housing base plate section 22. The output shaft hole 22a is defined at the center of the housing base plate section 22.

[0018] The lower bearing retaining section 24 is tubular and extends upwards from the housing base plate section 22. The lower bearing retaining section 24 is arranged radially outside the output shaft hole 22a. The lower bearing 81 is held by a radial inner surface of the lower bearing retaining section 24. The housing cover plate section 23 is connected to an upper end section of the housing tube section 21. The housing cover plate section 23 is arranged to cover a top surface of the control unit 70.

[0019] Connector section 25 is arranged to project upwards from housing cover plate section 23. Connector section 25 includes a recessed section (not shown) that is open at the top. A connection for the control unit 70 is exposed within the recessed section of connector section 25. An external power supply (not shown) is connected to connector section 25.

[0020] The rotor 30 comprises a shaft 31, a rotor core 32, and a rotor magnet 33. The shaft 31 has a central axis J, extending vertically. A lower end section of the shaft 31 is arranged to extend out of the housing 20 through the output shaft hole 22a.

[0021] The rotor core 32 is fixed to an outer circumferential surface of the shaft 31. The rotor magnet 33 is fixed to an outer circumferential surface of the rotor core 32. This means that the rotor magnet 33 is indirectly fixed to the shaft 31. The shaft 31, the rotor core 32, and the rotor magnet 33 are arranged such that they rotate together around the central axis J (i.e., in a ±θ z -Direction).

[0022] The sensor magnet 71 is attached to an upper end section of the shaft 31. In this preferred embodiment, the sensor magnet 71 is in the form of an annular ring. A mounting component 72 is fixed to the upper end section of the shaft 31. The sensor magnet 71 is fitted to an outer circumference of the mounting component 72.

[0023] The lower and upper bearings 81 and 82 are arranged to support the shaft 31. The lower and upper bearings 81 and 82 are arranged to support the shaft 31 such that the shaft 31 is rotatable about the central axis J (i.e., in the ±θ z (direction). The lower bearing 81 is located on the underside of the stator 40. The lower bearing retainer 24 is arranged to hold the lower bearing 81. The upper bearing 82 is located on the top side of the stator 40. The upper bearing retainer 50 is arranged to hold the upper bearing 82.

[0024] The stator 40 is arranged radially outside the rotor 30. More precisely, the stator 40 is arranged radially outside the rotor 30 in such a way that it surrounds the rotor 30. The stator 40 comprises a stator core 41, an insulator 42, and coils 43. The stator core 41 includes a core back 41a and a plurality of teeth 41b. The core back 41a is annular. In this preferred embodiment, the core back 41a is cylindrical or substantially cylindrical and is centered on the central axis J. An outer surface of the core back 41a is fixed to the inner circumferential surface 21a of the housing. The stator 40 is thus held by the inner circumferential surface 21a of the housing.

[0025] Although not shown in the figures, the stator core 41 includes the plurality of teeth 41b. The teeth 41b are arranged to extend radially inward from the core back 41a. The teeth 41b are arranged at regular intervals in the circumferential direction. The insulator 42 is attached to the teeth 41b. The insulator 42 includes an inner wall that extends axially at a radially inner end of the insulator 42 and an outer wall that extends axially at a radially outer end of the insulator 42. Each coil 43 is wound around a corresponding tooth 41b, with a section of the insulator 42 between them. Each coil 43 is arranged radially between the inner wall of the insulator 42 at its radially inner end and the outer wall of the insulator 42 at its radially outer end.The inner and outer walls of the insulator 42 serve to prevent each coil 43 from moving radially and thereby detaching from the insulator 42.

[0026] The upper bearing support 50 is arranged on the top of the stator 40. The upper bearing support 50 is positioned to hold the upper bearing 82. The upper bearing support 50 is positioned to be in contact with the inner circumferential surface 21a of the housing. In this preferred embodiment, the upper bearing support 50 is fixed to the inner circumferential surface 21a of the housing. The upper bearing support 50 is fixed to the inner circumferential surface 21a of the housing, for example, by a shrink fit.

[0027] Referring to the Fig. 1 and Fig. Figure 2 includes the upper bearing support 50, comprising a retaining section 51, an annular section 52, a lower section 53, a connecting section 54, and a buffer section 55. The retaining section 51 is tubular. An inner circumferential surface of the retaining section 51 is arranged to hold the upper bearing 82. In this preferred embodiment, the retaining section 51 is in the form of a cylinder, or essentially a cylinder with a cover having the central axis J as its center. The retaining section 51 includes a cover through-hole 51a, which is arranged to extend axially through a cover section of the retaining section 51. The upper end section of the shaft 31 is arranged to extend upwards above the upper bearing support 50 through the cover through-hole 51a.

[0028] The annular section 52 is arranged radially outside the holding section 51. Referring to Fig. 2 The annular section 52 is in the form of an annular ring and is arranged such that it extends in the circumferential direction and surrounds the retaining section 51. In this preferred embodiment, the annular section 52 is in the form of an annular ring and is centered on the central axis J. A radially outer end section of the annular section 52 is fixed to the inner circumferential surface 21a of the housing. Referring to Fig. 1. The annular section 52 is arranged at a higher level than that of a lower end section of the retaining section 51. The annular section 52 is arranged at a lower level than that of an upper end section of the retaining section 51. A lower surface of the annular section 52 is arranged at a higher level than that of an upper surface of the lower section 53.

[0029] Referring to Fig. 2 The annular section 52 includes a plurality of mounting through holes 52c and a plurality of intermediate sections 52d. This means that the upper bearing support 50 includes the plurality of mounting through holes 52c and the plurality of intermediate sections 52d. The mounting through holes 52c are arranged along the circumferential direction. Referring to Fig. 1. Each mounting through-hole 52c is arranged such that it passes axially through the upper bearing support 50. More precisely, each mounting through-hole 52c is arranged such that it passes axially through the annular section 52.

[0030] Referring to Fig. 2. Each mounting through-hole 52c is arranged to extend in a radial direction. A through-hole dimension L2 is defined as a circumferential dimension of the mounting through-hole 52c. The through-hole dimension L2 is larger at a radially outer end section of the mounting through-hole 52c than at a radially inner end section of the mounting through-hole 52c. The through-hole dimension L2 is smallest at the radially inner end section of the mounting through-hole 52c. The through-hole dimension L2 is arranged to increase radially outward. An outer shape of the mounting through-hole 52c is substantially triangular in plan view. It is noted that the outer shape of the mounting through-hole 52c could alternatively be a shape other than a triangle.

[0031] Referring to Fig. 1. Each mounting through-hole 52c is a hole arranged such that a coil wire 94, which is arranged to electrically connect a corresponding coil 43 to the busbar unit 60, passes through it. The coil wire 94 can either be an end section of a winding that defines the coil 43 or a separate component from the winding that defines the coil 43.

[0032] Referring to Fig. 2 The coil wire 94 is arranged such that it passes through the radially inner end section of the mounting through-hole 52c. The through-hole dimension L2 at the radially inner end section of the mounting through-hole 52c is arranged such that it has a minimum value that allows the passage of the coil wire 94.

[0033] It is noted that the radially inner end section of the mounting through hole 52c is not limited to a radially innermost end of the mounting through hole 52c. The radially inner end section of the mounting through hole 52c also includes a region surrounding the radially innermost end of the mounting through hole 52c. For example, the region surrounding the radially innermost end of the mounting through hole 52c covers an area extending radially outward from the radially innermost end of the mounting through hole 52c by approximately one thickness of the coil wire 94.

[0034] Each intermediate section 52d is a section that extends circumferentially between circumferentially adjacent mounting through holes 52c. An intermediate section dimension L1 is defined as a circumferential dimension of the intermediate section 52d. The intermediate section dimension L1 is smallest at a radially inner end section of the intermediate section 52d.

[0035] It is noted that the radially inner end section of the intermediate section 52d includes a section extending between the radially inner end sections of the circumferentially adjacent mounting through holes 52c. This means that the radially inner end section of the intermediate section 52d is not restricted to a radially innermost end of the intermediate section 52d. The radially inner end section of the intermediate section 52d also includes a region surrounding the radially innermost end of the intermediate section 52d. For example, the region surrounding the radially innermost end of the intermediate section 52d covers an area extending radially outward from the radially innermost end of the intermediate section 52d by approximately the thickness of the coil wire 94.

[0036] Here, the strength of the upper bearing support 50 increases with decreasing size of each support through-hole 52c (especially the area of ​​each support through-hole 52c in top view). Meanwhile, an increase in the size of the support through-hole 52c (especially the area of ​​the support through-hole 52c in top view) makes it easier for an operator or the like to guide the coil wire 94 through the support through-hole 52c when assembling the motor 10.

[0037] The strength of the upper bearing support 50 increases with increasing strength of each intermediate section 52d and decreases with decreasing strength of each intermediate section 52d. The strength of the intermediate section 52d is determined by a minimum value of the intermediate section dimension L1. In other words, the strength of the intermediate section 52d increases with increasing minimum value of the intermediate section dimension L1 and decreases with decreasing minimum value of the intermediate section dimension L1. Therefore, the strength of the upper bearing support 50 increases with increasing minimum value of the intermediate section dimension L1.

[0038] As mentioned above, each mounting through-hole 52c is a hole arranged such that the coil wire 94 passes through it. Accordingly, at a radial position where each coil wire 94 passes, a maximum circumferential distance between circumferentially adjacent mounting through-holes 52c corresponds to a circumferential distance between circumferentially adjacent coil wires 94. This means that a minimum value of the intersection dimension L1 corresponds to the circumferential distance between the circumferentially adjacent coil wires 94. In this case, at the radial position where each coil wire 94 passes, the through-hole dimension L2 has the minimum value that allows passage of the coil wire 94.

[0039] Accordingly, at the radial position where each coil wire 94 runs, the intermediate section dimension L1 is less than or equal to the circumferential distance between the circumferentially adjacent coil wires 94. Thus, if the intermediate section dimension L1 has its smallest value at the radial position where each coil wire 94 runs, the strength of the intermediate section 52d can be maximized. In this case, the strength of the upper bearing support 50 with the support through holes 52c can be maximized.

[0040] If the through-hole dimension L2 is arranged to have a larger value than the minimum value that allows the passage of the coil wire 94 at radial positions other than the radial position where each coil wire 94 runs, it is possible to minimize the intermediate section dimension L1 at the radial position where each coil wire 94 runs, while still allowing each mounting through-hole 52c to be of sufficient size. However, if the coil wire 94 were arranged to pass through the radially outer end section of the mounting through-hole 52c, it would be difficult to allow the mounting through-hole 52c to be of sufficient size.

[0041] If the through-hole dimension L2 is positioned such that it has the minimum value that allows the passage of the coil wire 94, the minimum value of the intermediate section dimension L1 can be maximized. If the through-hole dimension L2 with the minimum value that allows the passage of the coil wire 94 were positioned at the radially outer end section of the mounting through-hole 52c, and if the through-hole dimension L2 were increased radially inside the radially outer end section of the mounting through-hole 52c, the intermediate section dimension L1 would have a smaller value than the value of the intermediate section dimension L1 at the radial position where the coil wire 94 runs.

[0042] The strength of the intermediate section 52d is reduced if the through-hole dimension L2 is arranged with a larger value radially inside the radially outer end section of the bracket through-hole 52c than at the radially outer end section of the bracket through-hole 52c. This makes it difficult to increase the size of the bracket through-hole 52c while maintaining the strength of the upper bearing bracket 50 at a high level.Meanwhile, if the through-hole dimension L2 is arranged such that radially inside the radially outer end section of the bracket through-hole 52c it has a value less than or equal to the value of the through-hole dimension L2 at the radially outer end section of the bracket through-hole 52c, the strength of the upper bearing bracket 50 can be maintained at a high level, but the bracket through-hole 52c becomes so small that it becomes difficult for the operator or the like to guide the coil wire 94 through the bracket through-hole 52c when assembling the motor 10.

[0043] According to this preferred embodiment, however, the intermediate section dimension L1 is arranged such that it has its minimum value at the radially inner end section of the intermediate section 52d. Similarly, the through-hole dimension L2 is arranged such that it has the minimum value, allowing the passage of the coil wire 94, at the radially inner end section of the mounting through-hole 52c. This maximizes the strength of the intermediate section 52d. This, in turn, increases the strength of the upper bearing mount 50.

[0044] Additionally, the radially inner end section of the support through-hole 52c is located at the radial position where the coil wire 94 runs. Therefore, it is difficult to make the value of the intermediate section dimension L1 radially outside the radially inner end section of the intermediate section 52d smaller than the value of the intermediate section dimension L1 at the radially inner end section of the intermediate section 52d, even if the through-hole dimension L2 radially outside the radially inner end section of the support through-hole 52c is increased. Therefore, it is possible to increase the size of the support through-hole 52c to such an extent that the operator or the like can easily guide the coil wire 94 through the support through-hole 52c while maintaining a high level of strength in the upper bearing support 50.

[0045] The structure described above makes it possible to increase the area of ​​each bracket through-hole 52c. This reduces the amount of material used in the upper bearing bracket 50 when the upper bearing bracket 50 is formed by casting. This, in turn, reduces the manufacturing costs of the upper bearing bracket 501.

[0046] As described above, the upper bearing support 50 is fixed to the inner circumferential surface 21a of the housing. Accordingly, when an external force is applied to the housing 20, the external force exerts a load on the upper bearing support 50. Insufficient strength of the upper bearing support 50 could allow it to deform under the external force.

[0047] However, the upper bearing support 50 exhibits high strength, as described above. Therefore, the application of a large external force would not readily deform the upper bearing support 50. Furthermore, since deformation of the upper bearing support 50 does not readily occur, deformation of the inner circumferential surface 21a of the housing, to which the upper bearing support 50 is fixed, also does not readily occur.

[0048] The intermediate section dimension L1 is arranged such that it is essentially uniform over the entire radial extent of the intermediate section 52d. Accordingly, even if a load is applied to the upper bearing support 50 in a radial direction, this load is distributed uniformly in the circumferential direction within the upper bearing support 50. This further reduces the probability of deformation of the upper bearing support 50.

[0049] The through-hole dimension L2 is larger at the radially outer end section of the mounting through-hole 52c than at the radially inner end section of the mounting through-hole 52c, and is smallest at the radially inner end section of the mounting through-hole 52c. This allows the intermediate section dimension L1 to be substantially uniform over the entire radial extent of the intermediate section 52d.

[0050] It should be noted that both the intermediate section dimension L1 and the through-hole dimension L2 can be arranged so that they are uniform over the entire radial extent of the intermediate section 52d or the mounting through-hole 52c.

[0051] It is also noted that the radial position along which the coil wire 94 runs could be displaced from the radially inner end section of the mounting through-hole 52c. Fig. 2. The coil wire 94 runs through the radially inner end section of the mounting through-hole 52c. However, the coil wire 94 can alternatively be arranged to run through a different section of the mounting through-hole 52c. For example, the coil wire 94 can be arranged to run through a section of the mounting through-hole 52c that lies radially outside the radially inner end section of the mounting through-hole 52c (see Fig. 2).

[0052] An upper ring section surface 52a is an upper surface of the ring-shaped section 52. Referring to the Fig. 2 and Fig. 3 The upper ring section surface 52a includes a pass-through section 52b. The upper ring section surface 52a is a section of an upper surface of the upper bearing holder 50. This means that the upper surface of the upper bearing holder 50 includes the pass-through section 52b. Referring to Fig. 3 The pass hole section 52b is arranged such that it runs through the upper bearing support 50 in the axial direction. Referring to Fig. Figure 2 shows the outer shape of the pass hole section 52b as circular in plan view. A pass projection section 66, which will be described below, is fitted into the pass hole section 52b.

[0053] Referring to Fig. In section 3, the lower section 53 is arranged such that it extends radially outward from the lower end section of the retaining section 51. The lower section 53 defines a lower section of the buffer section 55. The connecting section 54 is arranged such that it connects a radially outer end section of the lower section 53 and a radially inner end section of the annular section 52. A lower end section of the connecting section 54 is connected to the radially outer end section of the lower section 53. An upper end section of the connecting section 54 is connected to the radially inner end section of the annular section 52. The connecting section 54 is arranged such that it extends in a direction that is angled radially outward, with increasing height with respect to the axial direction.

[0054] Each of the lower end sections of the retaining section 51, the lower end section of the lower section 53, and the lower end section of the connecting section 54 is arranged on a plane lower than that of an upper end section of the insulator 42 and is arranged radially within the insulator 42. The upper end section of the insulator 42 is an upper end section of each of the aforementioned inner and outer walls of the insulator 42. Thus, a section of the upper bearing support 50 can be arranged to radially overlap the insulator 42. In other words, a section of the upper bearing support 50 can be arranged to radially overlap the stator 40. This makes it possible to reduce the size of the motor 10 while efficiently utilizing space radially within the insulator 42.

[0055] The buffer section 55 is a section arranged to absorb a load exerted on the upper bearing 82. The buffer section 55 is arranged radially between the retaining section 51 and the annular section 52. The buffer section 55 is arranged to extend circumferentially, surrounding the upper bearing 82. Referring to Fig. 2 The buffer section 55 is in the form of an annular ring and is centered on the central axis J.

[0056] Referring to the Fig. 1 and Fig. 3. The buffer section 55 is a groove that is recessed in the axial direction. The buffer section 55 is a groove that is open at the top and recessed at the bottom. The buffer section 55 is defined by the fact that it is surrounded by the retaining section 51, the annular section 52, the lower section 53, and the connecting section 54.

[0057] As described above, the upper bearing support 50 is fixed to the inner circumferential surface 21a of the housing. Accordingly, when an external force is applied to the housing 20, the external force is also applied to the upper bearing support 50. The load applied to the upper bearing support 50 can be transferred to the upper bearing 82, thereby increasing the load applied to the upper bearing 82.

[0058] As described above, the upper bearing support 50 includes the buffer section 55. The buffer section 55 acts as a buffer to prevent the transfer of the load from the upper bearing support 50 to the upper bearing 82. This helps to reduce the load exerted on the upper bearing 82 when an external force is applied to the housing 20.

[0059] More precisely, the annular section 52 is fixed to the inner circumferential surface 21a of the housing. When an external force is applied to the housing tube section 21 from the radially outer side, a radially inward load is exerted on the annular section 52. This load exerted on the annular section 52, in turn, exerts a radially inward load on the upper end section of the connecting section 54. This load causes elastic deformation of the connecting section 54. Specifically, the load exerted on the connecting section 54 causes the lower end section of the connecting section 54 to pivot in the direction of the buffer section 55, i.e., radially inward.This elastic deformation of the connecting section 54 reduces or prevents the transmission of the load exerted on the annular section 52 to the upper bearing 82.

[0060] As described above, the buffer section 55 is a groove. Accordingly, the buffer section 55 can readily be defined by modifying the shape of at least one section of the upper bearing support 50 within the upper bearing support 50. This eliminates the need for the buffer section 55 to be provided as a separate component from the upper bearing support 50, thus eliminating the need to increase the number of parts of the motor 10.

[0061] The radial dimension of the buffer section 55 is arranged to increase with increasing height. This makes it easy to remove a mold when the upper bearing support 50 is formed by casting.

[0062] Referring to Fig. 1 The busbar unit 60 is arranged on the top of the upper bearing bracket 50. The busbar unit 60 is arranged such that it supplies an electrical drive current from the external power supply (not shown) to the stator 40. Referring to the Fig. 4 and Fig. 5 the busbar unit 60 is arranged so that it is in contact with the inner circumferential surface 21a of the housing.

[0063] The busbar unit 60 can be positioned relative to the inner circumferential surface 21a of the housing. The inner circumferential surface 21a is arranged to hold the stator 40. Thus, the busbar unit 60 and the stator 40 can be positioned relative to the inner circumferential surface of the same component. In other words, both the busbar unit 60 and the stator 40 can be positioned relative to the inner circumferential surface 21a of the housing. Both the busbar unit 60 and the stator 40 are fixed to the inner circumferential surface 21a of the housing with high positional accuracy. This allows the radial position of the busbar unit 60 relative to the stator 40 to be determined with high accuracy. This simplifies the electrical connection of the busbar unit 60 to the stator 40.

[0064] The housing 20 is made of metal. Therefore, the inner circumferential surface 21a of the housing can be precisely defined by machining or the like. This makes it possible to position the busbar unit 60 radially with high accuracy relative to the stator 40.

[0065] The busbar unit 60 includes a busbar support 61 and busbars 90. The busbar support 61 is arranged to hold the busbars 90. Each busbar 90 is electrically connected to the stator 40. Each busbar 90 includes a busbar body section 91, a busbar connection section 92, and coil connection sections 93.

[0066] Each busbar section 91 is arranged such that it extends in a plane (i.e., an xy-plane) perpendicular to the axial direction. The entire busbar section 91 is arranged in the same plane perpendicular to the axial direction. This results in a reduction of the axial dimension of the busbar unit 60. This, in turn, leads to a reduction of the axial dimension of the motor 10.

[0067] If the entire busbar body section 91 is arranged on the same plane, the area in which the busbar 90 is arranged can increase in radial dimension. Since this is the case in this preferred embodiment, the busbar unit 60 is arranged on the top of the upper bearing support 50. This allows for an increase in the radial dimension of the area in which the busbar 90 is arranged. This enables the entire busbar body section 91 to be arranged on the same plane, resulting in a reduction of the axial dimension of the motor 10.

[0068] The busbars 90 comprise a plurality of busbar body sections 91. In this preferred embodiment, the number of busbar body sections 91 is three. Only one of the busbar connection sections 92 is connected to each busbar body section 91. This means that the motor 10 is a three-phase motor, and each busbar 90 is a phase busbar connected to coils of one of the three phases (i.e., a U-phase, a V-phase, and a W-phase), and so on.

[0069] Referring to Fig. 1. At least one section of each busbar body section 91 is axially held between an upper busbar support 62 and a lower busbar support 63, as described below. At least one section of each busbar body section 91 is arranged such that it is in contact with both the upper and the lower busbar supports 62 and 63. Each busbar 90 is held by the busbar support 61.

[0070] The busbar connection section 92 is arranged so that it projects upwards from the busbar body section 91. An upper end section of the busbar connection section 92 is electrically connected to the control unit 70. The busbar unit 60 is electrically connected to the control unit 70. The busbar unit 60 is located on the top of the upper bearing support 50. This makes it easier to connect the busbar unit 60 to the control unit 70 when assembling the motor 10 than if the busbar unit 60 were arranged axially between the stator 40 and the upper bearing support 50.

[0071] Referring to Fig. 4. The busbars 90 include at least three busbar connection sections 92. The three busbar connection sections 92 are arranged at regular intervals along the circumferential direction. This means that at least one of the busbar connection sections 92 is located at each of three positions that, when viewed from above, divide the busbar support 61 into three equal parts in the circumferential direction.

[0072] Referring to the Fig. 1 and Fig. 4. Each busbar connection section 92 is in the form of a rectangular or substantially rectangular plate. Referring to Fig. 1 is a longitudinal direction of the busbar connection section 92 parallel to the axial direction. Referring to Fig. 4 is a width direction of the busbar connection section 92 parallel to the radial direction.

[0073] Each coil connection section 93 is connected to a corresponding busbar body section 91. The coil connection section 93 is arranged radially inside an inner edge of the upper busbar support 62, as will be described below. The coil connection section 93 is arranged radially outside an inner edge of the lower busbar support 63, as will be described below.

[0074] The outer shape of the coil connection section 93 is in the shape of the letter "U", with an open top surface facing radially outwards when viewed from above. Referring to Fig. 1. The coil connection section 93 is arranged to hold the corresponding coil wire 94. Each coil wire 94 is connected to the corresponding coil connection section 93 and the corresponding coil 43 and passes through the corresponding mounting through-hole 52c and a corresponding plurality of wire hole sections 63b, as will be described below. Each busbar 90 and the stator 40 are thus electrically connected to each other by the corresponding coil wires 94.

[0075] In the case where the upper bearing bracket 50 is arranged axially between the busbar assembly 60 and the stator 40, as described above, each coil wire 94 passes through the corresponding bracket through-hole 52c of the upper bearing bracket 50 and connects the stator 40 to the busbar assembly 60. Therefore, if the upper bearing bracket 50 is not positioned radially with sufficient accuracy relative to both the stator 40 and the busbar assembly 60, it may be difficult for the operator or similar person to guide each coil wire 94 through the corresponding bracket through-hole 52c when assembling the motor 10. Additionally, the coil wire 94 may be pressed against an edge of the corresponding bracket through-hole 52c, which could damage the coil wire 94.

[0076] In contrast, in this preferred embodiment, the upper bearing support 50 is arranged such that it is in contact with the inner circumferential surface 21a of the housing. Accordingly, the upper bearing support 50 is positioned relative to the inner circumferential surface 21a because both the stator 40 and the busbar assembly 60 are positioned relative to the inner circumferential surface 21a. This allows for highly accurate radial positioning of the upper bearing support 50 relative to both the stator 40 and the busbar assembly 60. Consequently, the operator or similar person can easily guide each coil wire 94 through the corresponding support through-hole 52c. Furthermore, this prevents the coil wire 94 from being pressed against the edge of the corresponding support through-hole 52c, thus avoiding damage to the coil wire 94.

[0077] Referring to Fig. Figure 1 includes the busbar support 61, the upper and lower busbar supports 62 and 63. The busbar support 61 is preferably made of a resin. The upper busbar support 62 is arranged such that it axially overlaps the lower busbar support 63. The upper busbar support 62 is located on the top side of the lower busbar support 63.

[0078] Referring to the Fig. 1, Fig. 4 and Fig. 5 The upper busbar support 62 includes an upper support body section 62a, an outer edge projection section 62b, a plurality of support projection sections 64, a fitting projection section 66 and connection carrier sections 68. This means that the busbar support 61 includes the upper support body section 62a, the outer edge projection section 62b, the support projection sections 64, the fitting projection section 66 and the connection carrier sections 68.

[0079] Referring to Fig. 4. The upper mounting body section 62a is ring-shaped. The upper mounting body section 62a is in the form of a ring and is centered on the central axis J. Referring to the Fig. 1 and Fig. 5 the outer edge projection section 62b is tubular and is arranged such that it projects downwards from a radially outer edge of the upper support body section 62a.

[0080] Referring to Fig. 4. Each mounting bracket extension section 64 is arranged such that it projects radially outwards from the upper mounting body section 62a. A radially outer end section of the mounting bracket extension section 64 is arranged such that it is in contact with the inner circumferential surface 21a of the housing. This means that the busbar unit 60 is arranged such that it is in contact with the inner circumferential surface 21a of the housing through the radially outer end section of each mounting bracket extension section 64.

[0081] The radially outer end section of each support protrusion section 64 is a section of a radially outer edge of the busbar support 61. Forming the radially outer end section of each support protrusion section 64 with high accuracy is simpler than forming the entire radially outer edge of the busbar support 61 with high accuracy. Accordingly, an improvement is achieved in the accuracy with which a section or sections of the busbar support 61 are formed that are arranged to be in contact with the inner circumferential surface 21a of the housing, which increases the accuracy with which the busbar assembly 60 is radially positioned with respect to the stator 40.

[0082] The upper busbar support 62 includes the majority of support extension sections 64. This means that the busbar support 61 includes the majority of support extension sections 64. In Fig. 4 is the number of mounting sections 64 included in the busbar bracket 61, three. The mounting sections 64 are arranged at regular intervals along the circumferential direction. This results in the busbar bracket 61 being held securely by the inner circumferential surface 21a of the housing.

[0083] The mounting bracket sections 64 are arranged at the same circumferential positions as those of the busbar connection sections 92. As described above, each mounting bracket section 64 is a section positioned to be in contact with the inner circumferential surface 21a of the housing, thereby radially positioning the busbar unit 60. Accordingly, the busbar bracket 61 is radially positioned with greater accuracy with respect to the inner circumferential surface 21a at the circumferential position of each mounting bracket section 64 and its surroundings than at other circumferential positions.

[0084] Arranging the mounting protrusions 64 at the same circumferential positions as the busbar connection sections 92 improves the accuracy with which each busbar connection section 92 is radially positioned relative to the stator 40. This makes it easy for the operator or the like to connect each busbar connection section 92 with a wire or the like when assembling the motor 10. In this preferred embodiment, each busbar connection section 92 is connected to the control unit 70. Thus, the busbar connection section 92 can be readily connected to the control unit 70.

[0085] A circumferential center of each support projection section 64 coincides with a circumferential center of a corresponding busbar connection section 92. This contributes to increasing the accuracy with which each busbar connection section 92 is positioned radially relative to the stator 40.

[0086] It is noted that when it is described herein that two objects are arranged at the same circumferential position, the intended meaning is that at least sections of the two objects are arranged at the same circumferential position when viewed from above, and not merely that the circumferential centers of the two objects are arranged at the same circumferential position. This means that at least one section of each support projection section 64 may be arranged at the same circumferential position when viewed from above as that of at least one section of the corresponding busbar connection section 92.

[0087] Referring to Fig. 3. The fitting projection section 66 is arranged such that it projects downwards from the upper mounting body section 62a. A lower mounting body section 63a includes a through-hole 63c that extends axially through it. The fitting projection section 66 is arranged such that it passes through the through-hole 63c and projects downwards below the lower mounting body section 63a. Referring to Fig. 5 is an outer shape of the pass projection section 66, circular in plan view.

[0088] Referring to Fig. 3 is a lower end section of the fitting projection section 66 arranged in the fitting hole section 52b of the upper bearing bracket 50. The fitting projection section 66 is fitted into the fitting hole section 52b of the upper bearing bracket 50. The busbar bracket 61 is positioned accordingly circumferentially and radially with respect to the upper bearing bracket 50.

[0089] Referring to Fig. 1. Each connection support section 68 is arranged such that it projects upwards from the upper support body section 62a. The connection support section 68 is arranged such that it covers a lower end section and its surroundings of a corresponding busbar connection section 92. The connection support section 68 is arranged such that it supports the corresponding busbar connection section 92. The busbar connection section 92 is arranged such that it projects upwards from the upper end section of the connection support section 68.

[0090] The number of connection support sections 68 is equal to the number of busbar connection sections 92. In this preferred embodiment, the number of connection support sections 68 included in the upper busbar support 62 is three. The three connection support sections 68 are arranged at regular intervals along the circumferential direction. This means that at least one of the connection support sections 68 is located at each of the three positions that, in a top view, divide the busbar support 61 into three equal parts in the circumferential direction.

[0091] Referring to the Fig. 1, Fig. 4 and Fig. 5 includes the lower busbar support 63 the lower support body section 63a, an inner edge projection section 63d, a plurality of butt sections 65 and a plurality of weld sections 67. This means that the busbar support 61 includes the lower support body section 63a, the inner edge projection section 63d, the plurality of butt sections 65 and the plurality of weld sections 76.

[0092] Referring to Fig. 5 The lower mounting body section 63a is ring-shaped. The lower mounting body section 63a is in the shape of a ring and is centered on the central axis J. Referring to Fig. 4 is an inner edge of the lower support body section 63a arranged radially within an inner edge of the upper support body section 62a. Referring to the Fig. 1 and Fig. 5 is an outer edge of the lower support body section 63a arranged radially inside the outer edge projection section 62b of the upper busbar support 62. The lower support body section 63a is fitted to an inner side of the outer edge projection section 62b.

[0093] Referring to Fig. 1 The lower mounting body section 63a includes the wire hole sections 63b, each of which is arranged such that it extends axially through the lower mounting body section 63a. Each wire hole section 63b is arranged such that the corresponding coil wire 94 passes through it. Referring to the Fig. 4 and Fig. 5 The lower mounting body section 63a includes the majority of wire hole sections 63b. The wire hole sections 63b are arranged along the circumferential direction. The wire hole sections 63b are arranged such that they axially overlap the coil connection sections 93. Referring to Fig. 1 The wire hole sections 63b are arranged such that they axially overlap the mounting through holes 52c.

[0094] The upper and lower bracket body sections 62a and 63a together define a bracket body section.

[0095] The inner edge projection section 63d is arranged such that it projects upwards from the inner edge of the lower support body section 63a. The inner edge projection section 63d is in the form of a tube that opens both upwards and downwards in the axial direction. The inner edge projection section 63d is cylindrical or substantially cylindrical and is centered on the central axis J. The upper end section of the support section 51 is arranged within the inner edge projection section 63d. This means that at least one section of the inner edge projection section 63d is arranged to radially overlap the support section 51. This allows the busbar unit 60 and the upper bearing support 50 to be arranged close together in the axial direction. This results in a reduction of the axial dimension of the motor 10.

[0096] Each impact section 65 is arranged such that it projects downwards from the lower support body section 63a. Referring to Fig. In this preferred embodiment, the abutment sections 65 are arranged at regular intervals along the circumferential direction. In this preferred embodiment, the number of abutment sections 65 contained in the lower busbar support 63 is three. The outer shape of each abutment section 65 is circular when viewed from above. It should be noted that the outer shape of each abutment section 65 may alternatively have a different shape when viewed from above.

[0097] A lower buttress surface 65a is a lower surface of the buttress section 65. The upper ring section surface 52a is the upper surface of the upper bearing support 50. Referring to Fig. 1. The lower butt section surface 65a is arranged such that it is in contact with the upper ring section surface 52a. The busbar unit 60 is positioned axially with respect to the upper bearing support 50. The butt sections 65 are arranged at regular intervals along the circumferential direction. This contributes to increased parallelism of the busbar unit 60 to the upper bearing support 50.

[0098] Referring to Fig. 5. The butt sections 65 are arranged at the same circumferential positions as those of the support projection sections 64. The support projection sections 64 are arranged at the same circumferential positions as those of the busbar connection sections 92. Accordingly, the butt sections 65 are arranged at the same circumferential positions as those of the busbar connection sections 92.

[0099] The busbar support 61 is positioned axially with respect to the upper bearing support 50 at the circumferential position of each connecting section 65 and its surroundings with greater accuracy than at other circumferential positions. Thus, arranging the busbar connection sections 92 at the same circumferential positions as the connecting sections 65 improves the accuracy with which each busbar connection section 92 is positioned axially with respect to the upper bearing support 50. This makes it easier to connect each busbar connection section 92 to the control unit 70.

[0100] Referring to Fig. 1. Each butt section 65 is arranged such that it axially overlaps a corresponding busbar connection section 92. In other words, each busbar connection section 92 is arranged directly above a corresponding butt section 65. Each butt section 65 is arranged such that it axially positions the busbar unit 60 with respect to the upper bearing support 50. Accordingly, each busbar connection section 92 is axially positioned with increased accuracy with respect to the upper bearing support 50.

[0101] Referring to Fig. 4. The weld sections 67 are arranged along the circumferential direction. Although not shown in the figures, each weld section 67 is arranged to project upwards from the lower support body section 63a. The weld section 67 is arranged to pass through a through-hole (not shown) defined in the upper support body section 62a and project upwards above the upper support body section 62a. An upper end section of the weld section 67 is welded to an upper surface of the upper support body section 62a. The upper support body section 62a is thus fixed to the lower support body section 63a.

[0102] The shape of the busbar support 61 is arranged such that it possesses rotational symmetry about the central axis J. If the shape of the busbar support 61 did not have rotational symmetry, the amount of resin flowing into a mold would vary at different circumferential positions when the busbar support 61 is manufactured by a resin casting process. Consequently, the resin would cure for different lengths of time at different circumferential positions, and the accuracy with which the busbar support 61 is formed would vary at these positions. Accordingly, the dimensional accuracy of the busbar support 61 could be reduced.

[0103] In contrast, in this preferred embodiment, the shape of the busbar support 61 is arranged such that it has rotational symmetry about the central axis J. This allows the amount of resin to be substantially uniform in the circumferential direction when the busbar support 61 is formed. This reduces or prevents a decrease in the forming accuracy of the busbar support 61. This leads to an increase in the forming accuracy of the busbar support 61, which in turn increases the accuracy with which the busbar unit 60 is positioned radially relative to the stator 40. Additionally, the accuracy with which the busbar unit 60 is positioned axially relative to the upper bearing support 50 can be increased.

[0104] As described above, at least one of the busbar connection sections 92 is arranged at each of the three positions that divide the busbar support 61 into three equal parts in the circumferential direction when viewed from above. The majority of connection support sections 68 are arranged to support the busbar connection sections 92. Thus, the majority of connection support sections 68 can be arranged to have rotational symmetry about the central axis J. This allows the shape of the busbar support 61 to have rotational symmetry about the central axis J.

[0105] It is noted that when a particular object is described herein as being arranged with rotational symmetry about the central axis J, the intended meaning is that the shape of the particular object is arranged such that it possesses exact or approximate rotational symmetry about the central axis J. This means that at least the mounting protrusion sections 64 or the connecting support sections 68 are arranged such that they possess rotational symmetry about the central axis J.

[0106] Referring to Fig. The control unit 70 is located on the top of the busbar unit 60. The control unit 70 is, for example, a motor control unit (MSE). The control unit 70 is electrically connected to the busbar unit 60 via the busbar connection sections 92. The control unit 70 is positioned so that it is in contact with the inner circumferential surface 21a of the housing. Accordingly, both the control unit 70 and the busbar unit 60 are positioned with respect to the inner circumferential surface 21a of the housing. This improves the accuracy with which the control unit 70 is positioned radially relative to the busbar unit 60. This simplifies the connection of the busbar unit 60 and the control unit 70.

[0107] Power is supplied to the control unit 70 via the connector section 25. Although not shown in the figures, the control unit 70 includes, for example, a rotary sensor and an inverter circuit. The rotary sensor is arranged axially opposite the sensor magnet 71. The rotary sensor is positioned to detect, for example, the rotational position or rotational rate of the rotor 30. The inverter circuit is positioned to control the electrical currents to be supplied to the stator 40 based on, for example, the rotational position or rotational rate of the rotor 30 detected by the rotary sensor. The rotary sensor could, for example, be a magnetoresistive element or a Hall effect sensor.

[0108] It is noted that the locating hole section 52b may not extend axially through the upper bearing support 50. In this case, the locating hole section 52b is a hole with a bottom surface and is recessed downwards from the upper ring section surface 52a.

[0109] It is noted that the shape of each mounting through-hole 52c is not restricted to any of the shapes mentioned above. The through-hole dimension L2 may be locally reduced at a point between the radially inner end section and the radially outer end section of the mounting through-hole 52c. In this case, the intermediate section dimension L1 is locally increased at the radial position of the point where the through-hole dimension L2 is locally reduced.

[0110] It is noted that the through-hole dimension L2 can be arranged such that it is substantially uniform over the entire radial extent of the mounting through-hole 52c. It is also noted that the intermediate section dimension L1 can be arranged such that it increases from the radially inner end section towards a radially outer end section of the intermediate section 52d.

[0111] It is also noted that the buffer section 55 could be an upwardly recessed groove. Furthermore, it is noted that the buffer section 55 could, for example, be a section in which an elastic component is arranged. In this case, the elastic component could be embedded in the upper bearing support 50 or could be arranged in the buffer section 55 defined by the groove, as shown in Fig. 3 is shown.

[0112] In Fig.1 The busbar support 61 comprises two separate components, namely the upper and lower busbar supports 62 and 63. However, it is noted that the busbar support 61 could alternatively be defined by a single monolithic component.

[0113] It is also noted that the busbar bracket 61 could also lack a bracket projection section 64. In this case, the entire radially outer edge of the busbar bracket 61 is arranged such that it is in contact with the inner circumferential surface 21a of the housing.

[0114] The busbars 90 could include at least three busbar connection sections 92. This means that the busbars 90 could include four or more busbar connection sections 92.

[0115] At least one of the busbar connection sections 92 could be arranged at each of the three positions that divide the busbar support 61 into three equal parts in the circumferential direction when viewed from above. This means that two or more of the busbar connection sections 92 can be arranged at any one of the three positions that divide the busbar support 61 into three equal parts in the circumferential direction when viewed from above. In the case where four or more of the busbar connection sections 92 are provided, one of the busbar connection sections 92 is arranged at each of the three positions that divide the busbar support 61 into three equal parts in the circumferential direction when viewed from above, and the other busbar connection section(s) 92 can be arranged at one or more arbitrary positions.

[0116] It is also noted that busbar sections 91 can alternatively be arranged at different axial positions. In this case, for example, the busbar sections 91 are arranged such that they axially overlap each other.

[0117] It is also noted that the housing 20 may not be made of a metal, but could alternatively be made of a resin, for example.

[0118] The rotor magnet 33 is fixed directly or indirectly to the shaft 31. This means that the rotor magnet 33 can alternatively be fixed directly to the shaft 31.

[0119] It is also noted that, alternatively, motor 10 may not include control unit 70.

[0120] Features of the preferred embodiments described above and their modifications can be suitably combined as long as no conflict arises.

[0121] While preferred embodiments of the present invention have been described above, it should be noted that variations and modifications will be recognizable to those skilled in the art without altering the scope and nature of the present invention. The scope of the present invention is therefore to be defined solely by the following claims.

Claims

[1] Motor (10) which has the following features: a rotor (30) with a shaft (31) having a central axis (J) extending in a vertical direction, as its center; a stator (40) arranged radially outside the rotor (30); a bearing located on the top side of the stator to support the shaft in a rotatable manner; a tubular housing (20) arranged to hold the stator (40); a bearing support (50) arranged on the top of the stator to hold the bearing; and a busbar unit (60) arranged on a top side of the bearing support to supply an electrical drive current to the stator; wherein: the rotor (30) has a rotor magnet (33) which is fixed directly or indirectly to the shaft; the stator (40) has the following features: a ring-shaped nucleus back (41a); Teeth (41b) arranged so that they extend radially inward from the nucleus dorsum; and Coils (43) wound around the teeth; the housing (20) has an inner circumferential surface (21a) arranged to hold the stator (40); the bearing holder (50) is arranged in contact with the inner circumferential surface (21a) of the housing; and the busbar unit (60) is arranged in contact with the inner circumferential surface of the housing (21a); wherein the busbar unit (60) has the following features: at least one busbar (90) which is electrically connected to the stator (40); and a busbar support arranged to hold at least one busbar; and the busbar support has the following features: a mounting body section; and a plurality of touch sections (65), each arranged in such a way that that they protrude downwards from the mounting body section; the majority of the impact sections (65) are arranged at regular intervals along a circumferential direction; and a lower surface of each bump section (65) is arranged such that it is in contact with an upper surface of the bearing support; wherein each of the at least one busbar (90) has the following features: a busbar section; and a busbar connection section (92) arranged so that it projects upwards from the busbar body section; and wherein each bump section (65) is arranged at the same circumferential position as that of the corresponding busbar connection section. [2] Motor (10) which has the following features: a rotor (30) with a shaft (31) having a central axis (J) extending in a vertical direction, as its center; a stator (40) arranged radially outside the rotor (30); a bearing located on the top side of the stator to support the shaft in a rotatable manner; a tubular housing (20) arranged to hold the stator (40); a bearing support (50) arranged on the top of the stator to hold the bearing; and a busbar unit (60) arranged on a top side of the bearing support to supply an electrical drive current to the stator; wherein: the rotor (30) has a rotor magnet (33) which is fixed directly or indirectly to the shaft; the stator (40) has the following features: a ring-shaped nucleus back (41a); Teeth (41b) arranged so that they extend radially inward from the nucleus dorsum; and Coils (43) wound around the teeth; the housing (20) has an inner circumferential surface (21a) arranged to hold the stator (40); the bearing holder (50) is arranged in contact with the inner circumferential surface (21a) of the housing; and the busbar unit (60) is arranged in contact with the inner circumferential surface of the housing (21a); wherein the busbar unit (60) has the following features: at least one busbar (90) which is electrically connected to the stator (40); and a busbar support arranged to hold at least one busbar (90); the busbar support has the following features: a mounting body section; and at least one mounting projection section arranged to project radially outwards from the mounting body section; and wherein the busbar support is arranged such that it is in contact with the housing inner circumferential surface by a radially outer end section of each of the at least one support projection section; wherein at least one bracket projection section has a plurality of bracket projection sections; and wherein the plurality of bracket projection sections are arranged at regular intervals along a circumferential direction. [3] Motor (10) which has the following features: a rotor (30) with a shaft (31) having a central axis (J) extending in a vertical direction, as its center; a stator (40) arranged radially outside the rotor (30); a bearing located on the top side of the stator to support the shaft in a rotatable manner; a tubular housing (20) arranged to hold the stator (40); a bearing support (50) arranged on the top of the stator to hold the bearing; and a busbar unit (60) arranged on a top side of the bearing support to supply an electrical drive current to the stator; wherein: the rotor (30) has a rotor magnet (33) which is fixed directly or indirectly to the shaft; the stator (40) has the following features: a ring-shaped nucleus back (41a); Teeth (41b) arranged so that they extend radially inward from the nucleus dorsum; and Coils (43) wound around the teeth; the housing (20) has an inner circumferential surface (21a) arranged to hold the stator (40); the bearing holder (50) is arranged in contact with the inner circumferential surface (21a) of the housing; and the busbar unit (60) is arranged in contact with the inner circumferential surface of the housing (21a); wherein the busbar unit (60) has the following features: at least one busbar (90) which is electrically connected to the stator (40); and a busbar support arranged to hold at least one busbar (90); the busbar support has the following features: a mounting body section; and at least one mounting projection section arranged such that it projects radially outwards from the mounting body section; and wherein the busbar support is arranged such that it is in contact with the housing inner circumferential surface by a radially outer end section of each of the at least one support projection section; wherein each of the at least one busbar (90) has the following features: a busbar section; and a busbar connection section (92) arranged so that it projects upwards from the busbar body section; and wherein at least one mounting protrusion section is arranged at the same circumferential position as that of the corresponding busbar connection section; wherein at least one busbar (90) has at least three busbar connection sections; and wherein at least one of the busbar connection sections (92) is arranged at each of three positions which divide the busbar support into three equal parts in a circumferential direction when viewed from above. [4] Motor (10) according to claim 1, 2 or 3, wherein the housing (20) is made of a metal. [5] Motor (10) according to claim 1, 2, 3 or 4, further comprising a control unit (70) arranged on a top side of the busbar unit (60), wherein the control unit is electrically connected to the busbar unit and is arranged in contact with the inner circumferential surface (21a) of the housing. [6] Motor (10) according to claim 2 or 3, wherein each of which has at least one busbar (90) exhibiting the following characteristics: a busbar section; and a busbar connection section (92) arranged so that it projects upwards from the busbar body section; and which at least one mounting protrusion section is arranged at the same circumferential position as that of the corresponding busbar connection section. [7] Motor (10) according to any one of claims 1 to 6, wherein: the busbar unit (60) has the following features: at least one busbar (90) that is electrically connected to the stator; and a busbar support arranged to hold at least one busbar; The busbar support has the following features: a mounting body section; and a fitting projection section (66) arranged to project downwards from the mounting body section; and an upper surface of the bearing holder has a fitting hole section (52b) into which the fitting protrusion section is fitted. [8] Motor (10) according to any one of claims 1 to 7, wherein: the bearing support has a buffer section (55) which is arranged to extend in a circumferential direction and surround the bearing, and is arranged to absorb a load exerted on the bearing; and the buffer section (55) has a groove which is recessed in an axial direction. [9] Motor (10) according to any one of claims 1 to 8, wherein: The bearing bracket has the following features: a plurality of mounting through holes (52c) arranged along a circumferential direction, each mounting through hole being arranged such that a coil wire (94) being arranged to electrically connect a corresponding coil to the busbar unit passes through it; an intermediate section (52d) defined circumferentially between circumferentially adjacent mounting through holes; each mounting through-hole (52c) is arranged such that it passes through the bearing mount in an axial direction and is arranged such that it extends in a radial direction; and a circumferential dimension of the intermediate section (52d) is smallest at a radially inner end section of the intermediate section. [10] Motor (10) according to claim 9, wherein a circumferential dimension of each mounting through-hole (52c) is larger at a radially outer end section of the mounting through-hole than at a radially inner end section of the mounting through-hole and is smallest at the radially inner end section of the mounting through-hole.

Images