CN110622396B - Motor and electric power steering apparatus - Google Patents

Abstract

Provided are a motor and an electric power steering device which are reduced in size in the axial direction. The motor (1) of the present invention comprises: a coil support member (60) which is formed of an insulating material and through which the coil wire (C) is inserted; and a heat sink (100) having a through hole through which the coil support member (60) is inserted, wherein the heat sink (100) is provided with a recess (111), the recess (111) is located at an upper end of the through hole, a bottom surface of the recess (111) is exposed when viewed from an upper side in the axial direction, and the upper surface of the coil support member (60) and the bottom surface of the recess (111) are different in axial position.

Description

Motor and electric power steering apparatus

Technical Field

The present invention relates to a motor and an electric power steering apparatus.

Background

An electromechanical motor is known in which a motor main body including a rotor and a stator and a control unit for controlling the motor main body are integrally arranged. Such a motor includes an electronic device disclosed in japanese patent application laid-open No. 2016-.

The electronic device disclosed in patent document 1 includes a housing including: an opposing surface disposed with a gap from the substrate; and a protruding portion that protrudes toward a position different from the electronic component, a height of the protruding portion of the case being greater than a height of the electronic component and smaller than the gap.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2016-034203

Disclosure of Invention

Problems to be solved by the invention

Patent document 1 discloses that the heat dissipating gel is prevented from falling into the shaft hole into which the shaft is inserted by providing a protrusion.

However, the electronic device of patent document 1 has a problem that the size in the axial direction is large because the protruding portion is provided.

In view of the above problems, an object of the present invention is to provide a motor and an electric power steering apparatus that reduce the axial dimension and prevent heat dissipation members such as heat dissipation gel from entering the stator.

Means for solving the problems

A motor according to one embodiment of the present invention includes: a rotor including a shaft extending in an axial direction; a stator surrounding a radial outer side of the rotor and including a coil formed by winding a coil wire; a coil support member made of an insulating material, disposed on an upper side in an axial direction of the stator, and through which the coil wire is inserted; a heat sink which is disposed on the upper side in the axial direction of the stator and has a through hole through which the coil support member is inserted; and a substrate arranged on an axially upper side of the heat sink and having an electronic component mounted thereon, wherein the heat sink is provided with a recess located at an upper end portion of the through hole, a bottom surface of the recess is exposed when viewed from the axially upper side, and an axial position of an upper surface of the coil support member is different from an axial position of the bottom surface of the recess.

Effects of the invention

According to one aspect of the present invention, it is possible to provide a motor and an electric power steering apparatus in which the dimension in the axial direction is reduced and a heat dissipation member is prevented from entering the inside of a stator.

Drawings

Fig. 1 is a sectional view of a motor according to embodiment 1.

Fig. 2 is a sectional view of the housing and the flange of embodiment 1.

Fig. 3 is an enlarged view of a region corresponding to a region III in fig. 2 in the motor according to the modification of embodiment 1.

Fig. 4 is another modification of fig. 3.

Fig. 5 is a bottom view of the cover of embodiment 1.

Fig. 6 is an enlarged view of region VI of fig. 1.

Fig. 7 is a modification of fig. 6.

Fig. 8 is another modification of fig. 6.

Fig. 9 is a further modification of fig. 6.

Fig. 10 is a schematic view of a stator of embodiment 1.

Fig. 11 is a perspective view of a bus bar holding member according to embodiment 1.

Fig. 12 is a perspective view of a coil support member according to embodiment 1.

Fig. 13 is a perspective view of a bus bar holding member and a coil support member according to embodiment 1.

Fig. 14 is a bottom view of the bus bar holding member and the coil support member of embodiment 1.

Fig. 15 is a bottom view of the substrate according to embodiment 1.

Fig. 16 is a sectional view of the substrate and the conductive member of embodiment 1.

Fig. 17 is a plan view of the heat sink according to embodiment 1.

Fig. 18 is a bottom view of the heat sink of embodiment 1.

Fig. 19A is a plan view schematically showing fig. 17.

Fig. 19B is a modification of fig. 19A.

Fig. 19C is a modification of fig. 19A.

Fig. 20 is a plan view of the heat sink and the coil support member supporting the coil wire of embodiment 1.

Fig. 21 is a sectional view taken along line XXI-XXI of fig. 20.

Fig. 22 is another sectional view taken along line XXI-XXI of fig. 20.

Fig. 23 is a schematic diagram showing a relationship between the heat sink through-hole and the coil support member in embodiment 1.

Fig. 24 is a schematic diagram showing another relationship between the heat sink through-hole and the coil support member in embodiment 1.

Fig. 25 is a schematic diagram showing still another relationship between the heat sink through-hole and the coil support member in embodiment 1.

Fig. 26 is an enlarged view of the heat sink through-hole and the coil support member in embodiment 1.

Fig. 27 is a modification of fig. 26.

Fig. 28 is a schematic view of a process of inserting a heat sink into a coil support member from above in embodiment 1.

Fig. 29A is a schematic view of a heat sink and a substrate.

Fig. 29B is a modification of fig. 29A.

Fig. 30 is a side view of the connector of embodiment 1.

Fig. 31 is a perspective view of the connector according to embodiment 1.

Fig. 32 is a perspective view of the heat sink and the connector of embodiment 1.

Fig. 33 is a schematic view of an electric power steering apparatus according to embodiment 2.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding portions are denoted by the same reference numerals, and the description thereof will not be repeated.

In the following description, as shown in fig. 1, the central axis a of the rotor, i.e., the axial direction in which the shaft extends, is referred to as the vertical direction. The substrate side is an upper side, and the bottom side of the case is a lower side. However, the vertical direction in the present specification is for specifying the positional relationship, and is not limited to an actual direction. That is, the lower direction does not necessarily mean the gravity direction.

The direction perpendicular to the center axis a of the rotor is a radial direction, and the radial direction is centered on the center axis a. The direction around the central axis a of the rotor is the circumferential direction.

In the present specification, "extend in the axial direction" includes a state of strictly extending in the axial direction and a state of extending in a direction inclined in a range of less than 45 degrees with respect to the axial direction. In addition, in the present specification, "extend in the radial direction" includes a state of strictly extending in the radial direction and a state of extending in a direction inclined in a range of less than 45 degrees with respect to the radial direction.

In the present specification, "fitting (fitting)" means fitting of members having matching shapes. The shape matching includes the case where the shapes are the same, the case where the shapes are similar, and the case where the shapes are different. When the members having matching shapes have a concave-convex shape, at least a part of one of the convex portions is positioned in the other concave portion.

In the present specification, "gap" means an intentionally provided gap. That is, a gap designed so that the members do not contact each other is used as the gap.

(embodiment mode 1)

A motor according to embodiment 1 of the present invention will be described with reference to fig. 1 to 27. The motor of embodiment 1 has a two-phase system configuration having two sets of U-phase, V-phase, and W-phase.

As shown in fig. 1, the motor 1 mainly includes a housing 10, a flange 20, a cover 30, a rotor 40, bearings 43 and 44, a stator 50, a coil support member 60, a control portion having a substrate 70 and an electronic component 80, a heat sink 100, and a connector 200.

< housing >

As shown in fig. 1, the housing 10 internally houses the rotor 40, the stator 50, and the bearings 43 and 44. The housing 10 extends in the axial direction and is open at the upper side.

As shown in fig. 2, the housing 10 includes a 1 st cylindrical portion 11, a contact portion 12, a 2 nd cylindrical portion 13, and a bottom portion 14. The housing 10 of the present embodiment is a press-molded product. The thicknesses of the 1 st tubular portion 11, the contact portion 12, the 2 nd tubular portion 13, and the bottom portion 14 are the same. The phrase "the same" means that the layers are not intentionally formed to have different thicknesses, and the layers are not necessarily formed to have the same thickness due to drawing in press forming.

The 1 st tubular portion 11 and the 2 nd tubular portion 13 are tubular with a center axis a as a center. The cylindrical shape means a hollow shape, and may be circular or polygonal in a plan view. The 1 st cylinder portion 11 accommodates the stator 50 therein.

The contact portion 12 extends radially inward from the axial lower end of the 1 st cylindrical portion 11. The stator 50 is in contact with the inner upper surface of the contact portion 12.

As shown in fig. 2, the housing lower surface 12a of the contact portion 12 is a flat surface extending in the radial direction. The housing lower surface 12a of the contact portion 12 may extend axially upward as it extends radially inward from the 1 st cylindrical portion 11 as shown in fig. 3, or may extend axially downward as it extends radially inward from the 1 st cylindrical portion 11 as shown in fig. 4. The case lower surface 12a of the contact portion 12 may be a curved surface, not shown.

The 2 nd cylindrical portion 13 extends axially downward from the radially inner end of the contact portion 12, is cylindrical, and has an outer diameter smaller than that of the 1 st cylindrical portion 11. The 2 nd cylindrical portion 13 includes an upper cylindrical portion 13a, a lower cylindrical portion 13b, and a connecting portion 13 c. The lower tube portion 13b has a smaller outer diameter than the upper tube portion 13 a. The connecting portion 13c connects the upper tube portion 13a and the lower tube portion 13 b.

The bottom portion 14 extends radially inward from the axial lower end of the 2 nd cylindrical portion 13. The bottom 14 closes the opening of the housing 10.

< Flange >

As shown in fig. 1 and 2, the flange 20 is attached to the outer side surface of the housing 10.

[ Structure of Flange ]

As shown in fig. 2, the flange 20 includes a flange cylindrical portion 21 and a flange flat portion 22. The flange 20 of the present embodiment is a press-molded article. The flange tube portion 21 and the flange flat portion 22 have the same thickness.

The flange cylindrical portion 21 is fixed to the outer surface of the 2 nd cylindrical portion 13 of the housing 10. The flange cylindrical portion 21 has a cylindrical shape centered on the central axis a, and the flange cylindrical portion 21 has an outer diameter larger than that of the 2 nd cylindrical portion 13. The axial length of the flange cylindrical portion 21 is shorter than the axial length of the 2 nd cylindrical portion 13.

The outer side surface and the inner side surface of the flange cylindrical portion 21 may extend in the axial direction as shown in fig. 2 and 3. Further, the upper portions of the outer surface and the inner surface of the flange tube portion 21 may be inclined as shown in fig. 4.

The flange flat surface portion 22 extends radially outward from the axial lower end of the flange cylindrical portion 21. The flange flat portion 22 protrudes radially outward of the 1 st cylinder portion 11 when viewed from the axially upper side. The flange flat portion 22 has fixing hole portions 23, and the fixing hole portions 23 are used for fixing to an external device of the motor 1 at a plurality of places.

[ contact of the case with the flange ]

As shown in fig. 1 to 4, the upper end 21a of the flange cylindrical portion 21 contacts the case lower surface 12a of the contact portion 12 of the case 10. That is, at least a part of the upper end 21a of the flange cylindrical portion 21 contacts at least a part of the case lower surface 12a of the contact portion 12.

In the contact structure shown in fig. 2, the case lower surface 12a of the contact portion 12 is a flat surface extending in the radial direction, the upper end 21a of the flange cylindrical portion 21 is a flat surface extending in the radial direction, and at least a part of the flat surface of the contact portion 12 is in contact with at least a part of the flat surface of the flange cylindrical portion.

In the contact structure shown in fig. 3, the contact portion 12 extends axially upward as it goes radially inward from the 1 st cylindrical portion 11. Since the upper end 21a of the flange cylindrical portion 21 is a flat surface extending in the radial direction, the corner portion between the upper end surface and the inner side surface of the flange cylindrical portion 21 enters the contact portion 12. Therefore, the case 10 is not easily detached from the flange 20.

In the contact structure shown in fig. 4, the contact portion 12 extends axially downward as it goes radially inward from the 1 st cylindrical portion 11. The upper end 21a of the flange cylindrical portion 21 is in contact with the case lower surface 12a of the contact portion 12 and extends axially outward along the contact portion 12. Therefore, the case 10 is not easily detached from the flange 20.

< cover >

As shown in fig. 1, the cover 30 covers the substrate 70 and at least a part of the upper side in the axial direction of the connector 200. As shown in fig. 5, the cover 30 includes a disk-shaped portion 30a overlapping the housing 10 when viewed from the upper side in the axial direction, and a rectangular portion 30b facing the connector. The rectangular-shaped portion 30b includes an outer end region R having a cover outer end edge 31 as a radially outer end edge. In addition, "cover outer end edge 31" refers to the outer end of cover 30. The "outer end region R" is a predetermined region from the cover outer end edge 31 toward the inside including the cover outer end edge 31.

As shown in fig. 5 and 6, the cover 30 includes a covering wall 32, a cover concave portion 33, a cover convex portion 34, and a cover stepped portion 35 (see fig. 1).

The shroud wall 32 extends downward in the axial direction from the cover outer end 31 as a radially outer end, and covers at least a part of a connector outer end 216 as a radially outer end of the connector 200 described later.

The cover recess 33 is formed radially inward of the covering wall 32 and is recessed in the axial direction. As shown in fig. 6, the axially upper side of the cover recess 33 is a flat surface. The cover recess 33 shown in fig. 6 is formed by a radially inner surface of the covering wall 32 and a radially outer surface of the cover protrusion 34.

The cover convex portion 34 extends axially downward at a position radially inward of the cover concave portion 33. Specifically, the hood-convex portion 34 extends in the longitudinal direction of the connector, and further extends in the width direction from both ends in the longitudinal direction. The longitudinal direction means the left-right direction in fig. 5, and the width direction means the up-down direction in fig. 5. As shown in fig. 6, the axially lower side of the shroud-convex portion 34 is a flat surface. The lower surface of the convex cover portion 34 is located below the substrate 70. The lower surface of the hood convex portion 34 is at the same height in the axial direction as the upper surface of the connector convex portion 215 described later or is located below the upper surface of the connector convex portion 215.

The shroud step 35 is located radially inward of the shroud projection 34 and is recessed axially upward.

The cover concave portion 33, the cover convex portion 34, and the cover stepped portion 35 are formed of a plurality of flat surfaces, but may be formed of a curved surface.

Further, a modified example of the structure of the outer end region R of the cover 30 will be described with reference to fig. 7 to 9. In fig. 7, the cover recess 33 is not formed by the inner surface of the covering wall 32, but is recessed upward in the axial direction at a distance from the covering wall 32. In fig. 8, the coating wall 32 and the shroud-protruding portion 34 protrude substantially equally in length toward the axial lower side. In fig. 9, a stepped structure is provided between the covering wall 32 and the cover recess 33.

< rotor >

As shown in fig. 1, the rotor 40 includes a shaft 41 and a rotor core 42. The shaft 41 has a substantially cylindrical shape centered on a central axis a extending in the axial direction. A rotor core 42 is fixed to the shaft 41. The rotor core 42 surrounds the radially outer side of the shaft. The rotor core 42 rotates together with the shaft 41.

< bearing >

As shown in fig. 1, bearings 43 and 44 support the shaft 41 so that the shaft 41 can rotate. The bearing 43 disposed on the upper side in the axial direction is located on the upper side in the axial direction of the stator 50 and is held by the heat sink 100. The bearing 44 disposed axially downward is held by the bottom 14 of the housing 10.

< stator >

[ Structure of stator ]

As shown in fig. 1, the stator 50 surrounds the radially outer side of the rotor 40. The stator 50 includes a stator core 51, an insulator 52, a coil 53, a bus bar B, and a bus bar holding member 54.

The stator core 51 has a plurality of core back portions and teeth 51b arranged in the circumferential direction (see fig. 10). The back of the iron core is in a cylindrical shape concentric with the central axis A. The teeth 51b extend from the inner side surface of the core back toward the radially inner side. The teeth 51b are provided in plural, extend in the radial direction from the core back, and are arranged with a gap (slot) in the circumferential direction.

As shown in fig. 1, the insulator 52 covers at least a portion of the stator core 51. The insulator 52 is formed of an insulator and attached to each tooth 51 b.

The coil 53 excites the stator core 51, and the coil 53 is formed by winding a coil wire C. Specifically, the coil wire C is wound around each tooth 51b with the insulator 52 interposed therebetween, and the coil 53 is disposed on each tooth 51 b. That is, the concentrated winding wire is used as the coil wire C. In the present embodiment, a so-called double continuous arc winding is used in which the coil wire C is wound so as to be concentrated with respect to the 2 different teeth 51 b. The coil wire C is located radially inward of the radially outer end of the bus bar holding member 54.

One end of the coil wire C is connected to the bus bar B. The other end of the coil wire C is inserted through a coil support member 60 described below and connected to the substrate 70. The other end of the coil wire C of the present embodiment is a lead wire drawn from the coil 53, and specifically, as shown in fig. 10, 6 lead wires 53U1, 53U2, 53V1, 53V2, 53W1, 53W2 that constitute each phase of U phase, V phase, and W phase of the 1 st and 2 nd systems. The lead wires 53U1, 53U2, 53V1, 53V2, 53W1, and 53W2 drawn out from the stator 50 are inserted into a through hole 65 (see fig. 12) of the coil support member 60 and a heat sink through hole 110 (see fig. 17) described later, and are electrically connected to the control unit by a method such as soldering.

The lead wires 53U1, 53U2, 53V1, 53V2, 53W1, and 53W2 are concentrated in a region of 180 degrees or less around the axis by the crossover wire 53 a.

When the motor 1 is driven, current is passed through the outgoing lines 53U1, 53V1, and 53W1 of the U-phase, V-phase, and W-phase phases constituting the 1 st system, and current is also passed through the outgoing lines 53U2, 53V2, and 53W2 of the U-phase, V-phase, and W-phase phases constituting the 2 nd system. With this configuration, even when the energization of the coil of one system is stopped due to, for example, a failure of the inverter or the like during driving of the motor 1, the energization of the coil of the other system is enabled, and therefore, the motor 1 can be driven.

The motor 1 of the present embodiment has a two-system configuration having two sets of U-phase, V-phase, and W-phase groups, but the number of systems can be arbitrarily designed. That is, the motor 1 may have a single-system configuration, or may have three or more systems.

The bus bar B is a member formed of a conductive material that electrically connects the coil wires led out from the coil 53 to each other. The bus bar B of the present embodiment is a neutral point bus bar in a star connection.

[ bus bar holding member ]

The bus bar holding member 54 shown in fig. 11 holds the bus bar B. The bus bar holding member 54 is formed of an insulating material. As shown in fig. 1, the bus bar holding member 54 is fixed to the radially outer side of the insulator 52 or the axially upper side of the core back. The bus bar holding member 54 radially overlaps the bearing 43.

As shown in fig. 11, the bus bar holding member 54 includes an annular base portion 55, a bus bar protrusion 57, and a holding portion 56 that holds the bus bar B. The bus bar protrusion 57 and the holding portion 56 extend axially upward from a part of the base portion 55 and are provided at different positions in the circumferential direction.

The stator 50 has a stator fitting portion that is a convex portion or a concave portion extending in the axial direction. In the present embodiment, the stator fitting portion is a bus bar protrusion 57 formed in the bus bar holding member and extending in the axial direction. The stator fitting portion may be a recess (not shown) formed in the bus bar holding member 54 and recessed downward in the axial direction. The stator fitting portion may be a convex portion or a concave portion formed at the upper end of the stator core 51, the insulator 52, or the like.

< coil supporting part >

As shown in fig. 1, the coil support member 60 supports a conductive member such as the coil wire C. The coil support member 60 is formed of an insulating material. The coil support member 60 is disposed axially above the stator 50, and through which the coil wire C is inserted.

[ Structure of coil support Member ]

As shown in fig. 12, the coil support member 60 includes a base portion 61 and a coil support portion 62 extending upward in the axial direction from the base portion 61. The coil support member 60 of the present embodiment includes a protrusion 62a through which the coil wire C is inserted. The base portion 61 is located axially below the projection portion 62a and extends radially.

Specifically, the base 61 is disposed on the upper surface of the stator 50. In the present embodiment, the stator fitting portion is formed in the bus bar holding member 54. Therefore, as shown in fig. 13 and 14, the base 61 is located on the upper surface of the bus bar holding member 54. In addition, when the stator fitting portion is formed in the stator core 51, the base portion 61 is positioned on the upper surface of the stator core 51, and when the stator fitting portion is formed in the insulator 52, the base portion 61 is positioned on the upper surface of the insulator 52.

As shown in fig. 12 and 13, notches 63 are formed at both circumferential ends of the axially lower portion of the base portion 61. The notches 63 are notched from the lower surface toward the axially upper side at both circumferential ends.

The base portion 61 has a groove portion 64 formed at an upper end and extending in the radial direction. The groove 64 is located axially above the upper end surface of the housing 10.

The radially outer surface of the base portion 61 is formed of a plurality of surfaces. In the present embodiment, the number of radially outer surfaces of the base portion 61 is 5. The radially outer surface of the base 61 may have a curved surface or the like.

The coil support 62 has a through hole 65 through which the coil wire is inserted. The coil wire of the present embodiment is formed of 6 lead wires 53U1, 53U2, 53V1, 53V2, 53W1, 53W2 for each of U-phase, V-phase, and W-phase of the 1 st and 2 nd systems. Since 1 lead wire is held by 1 through hole 65, 6 coil support portions 62 having the through holes 65 are provided on the base portion 61. In the present embodiment, the coil support portions 62 through which coil wires of the same phase are inserted are adjacent without a gap therebetween, and the protrusion portions 62a are formed. That is, the protrusion 62a includes a portion in which a through hole 65 through which the coil wire of the same phase is inserted and a rib 66 described later are formed. The U-phase, V-phase, and W-phase have protrusions 62a, and the protrusions 62a are arranged at intervals.

At least a part of the coil support portion 62 is positioned in a heat sink through hole 110 described later. The width of the coil support portion 62 shown in fig. 12 is equal to or gradually increases from the upper side toward the lower side in the axial direction, as compared with the width of the heat sink through hole 110. The width of the coil support portion 62 is smaller on the upper side than on the lower side. The coil support portion 62 has a shape that tapers toward the upper side.

The coil support portion 62 has ribs 66 extending in a direction intersecting the axial direction. In the present embodiment, the projection 62a includes ribs extending to both sides in the circumferential direction of the projection 62a and ribs extending from the through holes 65 to both sides in the radial direction. That is, each projection 62a has 6 ribs 66. The width of the rib 66 is equal to or gradually decreases from the lower side toward the upper side in the axial direction, and the width of the upper end of the rib 66 is smaller than the width of the lower end. That is, the shape of the coil support portion 62 having the rib 66 of the present embodiment is tapered toward the axially upper side. The projection 62a is also tapered toward the axially upper side.

[ fitting of stator to coil support Member ]

As shown in fig. 14, the base portion 61 is fitted to the stator 50 with a gap therebetween. The base 61 and the stator 50 may be partially in contact with each other, but are preferably arranged with a gap therebetween in a direction perpendicular to the axial direction. The direction perpendicular to the axial direction includes the radial direction and the circumferential direction. In the latter case, the entire coil support member 60 can move relative to the stator 50 when the motor 1 is assembled. In the present embodiment, the base portion 61 and the stator 50 are arranged with a gap in the circumferential direction.

The base portion 61 has a coil support member fitting portion 67, and the coil support member fitting portion 67 is a concave portion or a convex portion extending in the axial direction. The stator fitting portion and the coil support member fitting portion 67 are fitted with a gap therebetween by the concave portion and the convex portion.

The width in the radial direction of the concave portion of the stator fitting portion or the coil support member fitting portion 67 is larger than the width in the radial direction of the convex portion of the coil support member fitting portion 67 or the stator fitting portion. The width in the circumferential direction of the concave portion of the stator fitting portion or the coil support member fitting portion 67 is larger than the width in the circumferential direction of the convex portion of the coil support member fitting portion 67 or the stator fitting portion. Preferably, the stator fitting portion is a convex portion, and the coil support member fitting portion 67 is a concave portion, which are fitted with a gap in the circumferential direction. In other words, the stator 50 has a convex portion extending in the axial direction, the base portion 61 has a concave portion extending in the axial direction, the convex portion of the stator 50 and the concave portion of the base portion 61 are fitted with a gap in the circumferential direction, and the width of the concave portion of the base portion 61 in the circumferential direction is larger than the width of the convex portion of the stator 50 in the circumferential direction.

In the present embodiment, the coil support member fitting portion 67 is a concave portion formed in the base portion 61, and the stator fitting portion is a bus bar convex portion 57 formed in the bus bar holding member 54.

In this way, the stator 50 and the coil support member 60 are fitted to each other in the concave-convex shape, and the coil support member 60 is positioned at a predetermined position. Further, by fitting the coil support member 60 with a gap therebetween, the position of the coil support member 60 can be adjusted according to the width of the gap. This allows the heat sink 100 to be inserted while adjusting the position of the coil support member 60, which facilitates assembly. In addition, the relationship of the irregularities may be reversed so as to satisfy the above-described function.

Further, since the bus bar and the coil lead wire need to be fixed by welding, the bus bar holding member 54 needs to be fixed to a part of the stator 50. On the other hand, the coil support member 60 may be moved as long as the coil lead wire can be positioned.

The coil support member fitting portions 67 are located between the adjacent coil support portions 62 in the base portion 61. In other words, the coil support member fitting portions 67 are located between the adjacent protrusions 62a in the base portion 61. The coil support member fitting portion 67 is located on the lower surface of the base portion 61 in the axial direction and extends in the circumferential direction (the arrangement direction).

< control part >

The control unit controls a motor main body having the rotor 40 and the stator 50. As shown in fig. 1, the control unit includes a substrate 70 and an electronic component 80 mounted on the substrate 70. The base plate 70 is located on the axially upper side of the stator 50 and is configured to expand in the radial direction. The substrate 70 is fixed to the axial upper side of the heat sink 100. The electronic component 80 is mounted on at least one of the upper surface and the lower surface of the substrate 70.

As shown in fig. 15, the substrate 70 has a 1 st region S1 where power elements are mounted and a 2 nd region S2 where control elements are mounted. The 1 st region S1 is a region of 180 degrees or more centered on the central axis a of the shaft 41 when viewed from the axially upper side.

Here, when the power element and the control element are disposed on the substrate 70 so as to be separated in the circumferential direction, the 1 st region S1 and the 2 nd region S2 can be defined. Therefore, the following does not apply: the power elements and the control elements are irregularly scattered on the substrate 70; or the power element and the control element are located at the same circumferential position and are arranged separately in the radial direction.

The 1 st region S1 and the 2 nd region S2 are regions defined by an angle around the shaft 41 (central axis a). For example, even when the power element is shifted radially inward of the substrate 70 in the 1 st region S1, the radially outward side of the substrate 70 is regarded as the 1 st region S1.

Here, the power element refers to an element connected to an electric circuit of an external power supply from the coil wire, and the control element refers to an element connected to an electric circuit of an external control device from a signal wire detected by the magnetic sensor. The power element may be a choke coil, an FET, a capacitor, or the like. Examples of the control element include a microcomputer.

[ Structure of substrate ]

As shown in fig. 15, the substrate 70 has substrate through holes 71 and 72 through which the conductive members pass. The conductive member is connected to the substrate 70 to distribute power, and is, for example, a connector pin 81 (see fig. 1), a coil wire C wound around the stator 50, or the like. In the present embodiment, the coil wire is inserted through the board through hole 71, and the connector pin 81 is inserted through the board through hole 72. The coil wire C and the board 70, and the connector pin 81 and the board 70 are fixed by soldering.

Specifically, as shown in fig. 16, the substrate 70 includes a printed board 73 and pads 74, and the pads 74 surround a substrate through-hole 71 formed in the printed board 73. The lands 74 are located on the upper and lower surfaces of the printed board 73 and the inner surface of the board through-hole 71.

As shown in fig. 15, positioning hole portions 76 corresponding to the 2 nd positioning concave portion 176 (see fig. 17) of the heat sink 100 are formed in the substrate 70 for positioning with the heat sink 100. The positioning hole portion 76 is a circular hole, a cutout hole, or the like.

In addition, the substrate 70 is formed with fixing holes 77 corresponding to the fixing holes 177 (see fig. 17) of the heat sink main body 103 in order to fix the heat sink 100. The fixing hole portion 77 is a circular hole, a cutout hole, or the like.

[ relationship with Heat sink and connector ]

The 1 st positioning hole 178 penetrates the heat sink upper surface 101 and the heat sink lower surface 102. When the heat sink upper surface 101 is machined, the 2 nd positioning recess 176 is formed with the 1 st positioning hole 178 as a reference. In addition, when the heat sink lower surface 102 is machined, the 1 st positioning recess 179 is formed with the 1 st positioning hole 178 as a reference. Thus, the 1 st positioning recess 179 and the 2 nd positioning recess 176 are positioned with reference to the 1 st positioning hole 178.

Therefore, the connector 200 positioned by the 1 st positioning recess 179 is positioned with the substrate 70 positioned by the 2 nd positioning recess 176. This prevents positional deviation between heat sink 100 and connector 200, and connector pins 81 can be easily connected.

[ connection with conductive Member ]

The substrate 70 or the electronic component 80 and the conductive member are connected by the connection member 75. In fig. 16, the conductive members are a substrate 70 and a coil wire C. The connecting member 75 is a conductive adhesive, solder, or the like, and solder is used in the present embodiment. The solder is arranged so as to be connected to the upper surface and the lower surface of the substrate 70 and the inside of the substrate through-hole 71 for passing the conductive member. All the solder is positioned axially above an exposed surface 122 (see fig. 1) of the heat sink 100 described later.

< radiator >

As shown in fig. 1, the heat sink 100 is disposed axially above the stator 50 and axially faces the substrate 70.

The heat sink 100 has a function of absorbing heat from the electronic component 80 mounted on the substrate 70 and releasing the heat to the outside, and is formed of a material having low thermal resistance.

The heat sink 100 holds the bearing 43 and thus also serves as a bearing retainer. In the present embodiment, the bearing holder and the heat sink are integrated, and therefore the number of components, the number of assembly steps, and the cost associated therewith can be reduced. Further, since the thermal resistance generated when the bearing holder and the heat sink are separated from each other can be suppressed, heat can be easily transmitted to the outside.

The heat sink 100 has a heat sink upper surface 101 shown in fig. 17 and a heat sink lower surface 102 shown in fig. 18. The heat sink upper surface 101 faces the substrate 70, and the heat sink lower surface 102 faces the stator 50.

[ radiator main body part and radiator protrusion ]

As shown in fig. 17 and 18, the heat sink 100 includes a heat sink main body 103 and a heat sink protrusion 104, and the heat sink protrusion 104 is connected to the heat sink main body 103 and extends to a position radially outward of the housing 10.

The heat sink main body 103 overlaps the housing 10 that houses the rotor 40 and the stator 50 when viewed from the upper side in the axial direction. The heat sink protrusion 104 protrudes from the heat sink body 103 in the radial direction, and covers at least a part of the connector 200 in the longitudinal direction (the left-right direction in fig. 17 and 18).

A plurality of the heat sink protruding portions 104 shown in fig. 17 and 18 are formed at intervals. In detail, heat sink protruding portions 104 protrude from one end and the other end of the radially outer end edge of heat sink main body portion 103 on the connector 200 side. In fig. 19A, the right end of the heat sink main body portion 103 is the "radially outer end edge", and the upper and lower ends are the "one end and lower end".

Here, as shown in fig. 19A, the shape of the heat sink protruding portion 104 is a bar-like protruding shape in plan view, and when only provided at both ends, the heat sink protruding portion 104 and the heat sink main body portion 103 form a substantially U-shape. The shape of the heat sink protrusion 104 may be a plate-like protrusion as shown in fig. 19B, a ring-like protrusion as shown in fig. 19C, or the like. When the heat sink protruding portion 104 has a shape protruding like a rod in a plan view, one heat sink protruding portion 104 may be provided, or three or more heat sink protruding portions may be provided, or both ends may not be provided.

The heat sink protrusion 104 has a heat sink concave portion or a heat sink convex portion extending in the axial direction for fitting with a connector 200 described later. In addition, the heat sink concave portion or the heat sink convex portion extends in the axial direction. In fig. 17 and 18, a heat sink recess 105 is formed on the inner side surface of the heat sink protrusion 104 located at one end and the other end in the longitudinal direction of the connector 200. The inner surface of the heat sink protrusion 104 is a surface facing the connector 200.

In the present embodiment, the heat sink protrusion 104 is the exposed surface 122 (see fig. 1). That is, a gap is provided between the heat sink protrusion 104 and the substrate 70. Therefore, in the preliminary step of mounting the cover 30, whether or not the connector pins 81 are connected to the board 70 can be visually checked along the longitudinal direction of the connector 200.

[ hollow part ]

The heat sink 100 is formed with a hollow portion H through which the conductive member passes and which extends in the axial direction. The hollow portion H is a through hole, a notch, or the like.

In the case where the conductive member is the connector pin 81 or the like, in the configuration shown in fig. 17, fig. 18, and fig. 19A schematically illustrating them, the hollow portion H for passing the conductive member is formed by the heat sink main body portion 103 and 2 heat sink protrusions 104. In detail, the cavity portion H is formed by the outer edge in the radial direction of the connector side of the heat sink main body portion 103 and 2 heat sink protruding portions 104.

In a structure having a notch at the radial outer end of the heat sink protrusion 104 shown in fig. 19B of the modification, the notch forms a cavity H. In a configuration in which the radiator protrusion 104 shown in fig. 19C of another modification is ring-shaped, a hollow hole in the shape of a ring forms the hollow portion H.

In the case where the conductive member is a coil wire from the stator 50, as shown in fig. 17 and 18, a heat sink through hole 110 through which the coil wire passes and which extends in the axial direction is formed as the hollow portion H.

In this way, the cavity H of the heat sink 100 shown in fig. 17 and 18 is a cavity for a conductive member from a connector and a heat sink through hole 110 for a coil wire, which are formed by the radially outer end surface of the heat sink main body portion 103 and the inner end surfaces of the 2 heat sink protruding portions 104.

[ radiator through hole ]

As shown in fig. 17, 18, and 20, the heat sink through-hole 110 is passed through by a conductive member such as a coil wire and extends in the axial direction. Therefore, the heat sink through-hole 110 can position the conductive member. As shown in fig. 1 and 20, the heat sink through-hole 110 of the present embodiment holds the coil support member 60 that supports the coil wire.

The plurality of radiator through holes 110 are arranged adjacent to each other in the circumferential direction. Specifically, the plurality of radiator through holes 110U, 110V, and 110W are provided at intervals in the circumferential direction. That is, the plurality of radiator through holes 110U, 110V, and 110W are arranged on concentric arcs with a space therebetween.

As shown in fig. 17, the plurality of radiator through holes 110U, 110V, and 110W are located in a region where a central angle α around the shaft 41 (central axis a) is 180 degrees or less when viewed from the upper side in the axial direction. That is, the radiator through holes 110U, 110V, and 110W are collectively arranged on one side. Preferably, the number of slots is 6 or more, the number of phases is 3, and the central angle α is ″ (360 degrees/number of slots) × 3 ″ degrees or less.

The "phase" in the above formula refers to the number of independent coils for fixing the stator, and the 3-phase motor with 3 phases refers to a motor having 3 coils separated at 120-degree intervals, and in the present embodiment, is a 3-phase motor of U-phase, V-phase, and W-phase. The "groove" in the above formula represents the number of grooves between teeth, and is a multiple of 3 in a 3-phase motor. In the present embodiment, since there are 12 slots of 3 phases, the central angle α is preferably 90 degrees or less.

Further, similarly to the heat sink through holes 110U, 110V, and 110W, the coil lead wires 53U1, 53U2, 53V1, 53V2, 53W1, and 53W2 are also preferably arranged so as to be positioned within the central angle α. By using the crossover wire 53a, the coil lead wire can be positioned within the central angle α.

As shown in fig. 20, only the plurality of coil wires of the same phase among the coil wires are inserted through each of the plurality of heat sink through holes 110U, 110V, and 110W. That is, one projection 62a of the coil support member 60 is held in each of the heat sink through holes 110U, 110V, and 110W. The plurality of heat sink through holes 110U, 110V, and 110W are holes separated from each other for each phase of the coil wire. That is, the plurality of radiator through holes 110U, 110V, and 110W are independent of each other and are not connected. Specifically, only 2 lead wires 53U1 and 53U2 as U-phase coils are inserted through the heat sink through hole 110U. Only 2 lead wires 53V1 and 53V2 as V-phase coils are inserted through the heat sink through-hole 110V. Only 2 lead wires 53W1, 53W2 as W-phase coils are inserted through the heat sink through-hole 110W.

The heat sink through holes 110U, 110V, and 110W face the substrate 70 in the 1 st region S1 where the power element is mounted, when viewed from the upper side in the axial direction. Therefore, the heat sink through holes 110U, 110V, and 110W through which the coil wire passes are formed in the 1 st region S1 of the substrate 70 where the power element is mounted.

In addition, the following configuration is also possible: the heat sink through holes 110U, 110V, 110W span the 1 st region S1 where the power element is mounted and the 2 nd region S2 where the control element is mounted, as viewed from the axially upper side. Further, the following structure is also possible: when viewed from the axially upper side, a part of the radiator through-hole is located in the 1 st region S1, and the remainder is located in the 2 nd region S2.

[ recess at the upper end of radiator through-hole ]

As shown in fig. 21 and 22, the heat sink 100 is provided with a recess 111, the recess 111 is located at an upper end of the heat sink through hole 110, and a bottom surface (recess bottom surface 113) of the recess 111 is exposed when viewed from an upper side in the axial direction. That is, the recess 111 provided at the upper end of the radiator through hole 110 is a countersink-shaped recess formed by countersinking. The recess bottom surface 113 is a surface of the recess 111 located axially below.

The recess 111 is provided radially inward of the radiator through hole 110. The recess 111 may be located at an upper end of at least a part of the radiator through hole 110, and may be provided radially outward of the radiator through hole 110.

The recess 111 is composed of a heat sink upper surface 101, a recess side surface 112 extending downward from the heat sink upper surface 101, and a recess bottom surface 113 continuous with a lower end of the recess side surface 112. In the present embodiment, the heat sink upper surface 101 is parallel to the recess bottom surface 113. The through-hole side surface 110a of the heat sink through-hole 110 is parallel to the recess side surface 112. The through-hole side surface 110a is a surface extending downward from the recess bottom surface 113 in the heat sink through-hole 110.

As shown in fig. 21, the intersection angle D1 between the through-hole side surface 110a and the recess bottom surface 113 is 90 degrees or less. When the through-hole side surface 110a and the recess side surface 112 are parallel to each other, the intersection angle D2 between the recess side surface 112 and the recess bottom surface 113 is 90 degrees or less. When the recess bottom surface 113 is parallel to the heat sink upper surface 101 or the recess bottom surface 113 extends upward in the axial direction as it goes into the heat sink through hole 110, the intersection angle D2 between the recess side surface 112 and the recess bottom surface 113 is 90 degrees or less.

The connection member 75 connecting the coil wire C and the substrate 70 is located at least in a part of the concave portion 111. When the connection member 75 is made of solder, a back surface weld occurs during soldering. Therefore, the concave portion 111 functions as a back surface bead escape.

[ positional relationship between the recess and the coil support member ]

As shown in fig. 1, 21, and 22, the coil support member 60 is inserted through the heat sink through-hole 110. As shown in fig. 21 and 22, the upper surface 60a of the coil support member 60 and the recess bottom surface 113 have different axial positions. In the structure shown in fig. 21, the upper surface 60a of the coil support member 60 is positioned axially below the recess bottom surface 113. In the structure shown in fig. 22, the upper surface 60a of the coil support member 60 is positioned axially above the recess bottom surface 113.

The upper end portion of the coil support member 60 has a tapered portion 60b, and the width of the tapered portion 60b becomes narrower toward the axially upper side. In the structure shown in fig. 21, a space as a cavity for accommodating the heat dissipation member 123 can be formed by the side surface of the tapered portion 60b of the coil support member 60 and the through-hole side surface 110 a. In the structure shown in fig. 22, a space as a cavity for accommodating the heat dissipation member 123 can be formed by the side surface of the tapered portion 60b of the coil support member 60 and the recess 111.

Here, the "space as a cavity" refers to a space having an open upper surface and a closed lower surface. The "space as a cavity" may not have a bottom shape, and a gap may be formed in a side surface.

Lower end 60b1 of tapered portion 60b is located axially below recess bottom surface 113. In this case, a space as a cavity for accommodating the heat dissipation member 123 can be formed by the side surface of the tapered portion 60b located axially below the recess bottom surface 113 and the through-hole side surface 110 a.

As shown in fig. 22, the upper end (upper surface 60a in the present embodiment) of tapered portion 60b is positioned axially above recess bottom surface 113. In this case, a space as a cavity for accommodating the heat dissipation member 123 can be formed by the side surface of the tapered portion 60b located axially above the recess bottom surface 113 and the recess 111.

As shown in fig. 23 to 25, the base portion 61 of the coil support member 60 at least partially overlaps the heat sink through-hole 110 when viewed in the axial direction. That is, the base portion 61 having a width larger than the width of the heat sink through hole 110 is located below the heat sink through hole 110. In the structure shown in fig. 23 to 25, in the coil support member 60, a gap is left between the protrusion 62a through which the coil wire C is inserted and the heat sink through-hole 110, and when the heat sink through-hole 110 is viewed from the axial upper side, the gap overlaps the base 61. Therefore, a space as a cavity for accommodating the heat dissipation member 123 can be formed by the gap and the base 61.

As shown in fig. 21 and 22, the through-hole side surface 11a located axially below the recess 111 is preferably close to the coil support member 60, and the through-hole side surface 111a is preferably in contact with the coil support member 60.

[ fitting between Heat sink and coil support Member ]

As shown in fig. 1, at least a part of the coil support portion 62 is positioned in the heat sink through hole 110. As shown in fig. 1, 26, and 27, the gap between the coil support portion 62 and the heat sink through hole 110 becomes smaller or the same as going downward.

Specifically, as shown in fig. 26, the width of the upper end of the coil support portion 62 is smaller than the width of the lower end of the heat sink through hole 110, and the width of the coil support portion 62 is equal or gradually increases from the upper side toward the lower side. More specifically, the heat sink through hole 110 has a constant width, and the side surface of the coil support portion 62 has a tapered shape that expands downward.

As shown in fig. 27, the width of the lower end of the heat sink through-hole 110 is larger than the width of the upper end of the coil support portion 62, and the width of the heat sink through-hole 110 is equal to or gradually decreases from the lower side toward the upper side in the axial direction. More specifically, the heat sink through hole 110 has a tapered shape expanding downward, and the side surface of the coil support portion 62 has a constant width.

In fig. 26 and 27, the width of the upper end of the heat sink through hole 110 is larger than the width of the coil support portion 62, but the width of the upper end of the heat sink through hole 110 may be smaller than the width of the coil support portion 62.

Since the gap between the coil support 62 and the heat sink through-hole 110 is equal to or larger from the lower side toward the upper side in this way, the heat sink through-hole 110 can be easily inserted from the upper side of the coil support member 60 when the motor 1 is assembled.

When the heat sink 100 is inserted from above the coil support member 60, the positioning can be easily performed by the groove portion 64 (see fig. 12) of the coil support member 60. The reason for this is as follows. As shown in fig. 28, when the heat sink 100 is inserted from the axial upper side to the coil support member 60 as shown by arrow M in a state where the pin P is inserted in the radial direction near the groove portion 64 on the upper end surface of the base portion 61, the pin P moves toward the groove portion 64 because the pin P is pressed by the heat sink 100. Since the coil support member 60 moves in accordance with the arrow N in response to the pressing of the pin P, the heat sink 100 and the coil support member 60 can be positioned. The coil support portion 62 is inserted into the heat sink through hole 110 and positioned. Since the groove portion 64 is positioned axially above the upper end surface of the housing 10, the inserted pin P can be easily pulled out.

[ exposed surface and contact surface ]

As shown in fig. 1, the heat sink 100 has a contact surface 121 and an exposed surface 122. The contact surface 121 and the exposed surface 122 are surfaces located on the upper surface of the heat sink 100 shown in fig. 17.

The contact surface 121 is in contact with the substrate 70 or the electronic component 80 directly or through a heat dissipation member 123. The heat radiating member 123 is a member having heat radiation such as grease. The heat dissipation member 123 is in contact with the heat sink 100 and the substrate 70. The exposed surface 122 is exposed and does not contact the substrate 70, the electronic component 80, and the heat dissipation component. In other words, the exposed surface 122 is disposed with a gap from the substrate 70 or the electronic component 80. That is, the contact surface 121 is in direct or indirect contact with the substrate 70 or the electronic component 80, and the exposed surface 122 does not have a direct or indirect contact member.

As shown in fig. 17, the exposed surface 122 is located on the outer edge side of the hollow portion H (the heat sink through hole 110 in fig. 17). In the present embodiment, since the plurality of radiator through holes 110 are provided along the circumferential direction, the exposed surface 122 is located radially outward of the radiator through holes 110. The boundary between the contact surface 121 and the exposed surface 122 is located in the circumferential direction. In fig. 17, the boundary between the contact surface 121 and the exposed surface 122 is located on an arc having a central angle α connecting the radiator through hole 110U located at one end, the radiator through hole 110W located at the other end, and the central axis a.

Since a gap is formed between the substrate 70, the electronic component 80, and the heat sink 100 by the exposed surface 122, the connection between the substrate 70 or the electronic component 80 and the conductive member can be visually confirmed. When the connection is confirmed from the upper surface of the board 70, the connection by the connection member is not clear within the board through hole 71 and within the range of the lower surface of the board 70, and therefore, it is preferable to confirm from the lower surface side of the board 70.

In the heat sink 100 shown in fig. 1, the exposed surface 122 is located axially below the contact surface 121. Fig. 29 schematically shows the relationship between the vicinity of the boundary between the exposed surface 122 and the contact surface 121 and the substrate 70. As shown in fig. 29A, the substrate 70 may have a flat plate shape, and the exposed surface 122 may be located below the contact surface 121. As shown in fig. 29B, the substrate 70 may have a step structure, and the exposed surface 122 and the contact surface 121 may be located on the same plane.

The contact surface 121 may have a 1 st contact surface directly contacting the substrate 70 or the electronic component 80 and a 2 nd contact surface contacting the substrate 70 or the electronic component 80 with the heat dissipation member 123 interposed therebetween.

In order to confirm the shape of the lower end portion (back surface bead) of the connecting member connecting the electronic component 80 or the substrate 70 and the conductive member, it is preferable that the gap between the substrate 70 or the electronic component 80 and the exposed surface 122 is larger than the gap between the substrate 70 or the electronic component 80 and the 2 nd contact surface. In addition, from the viewpoint of preventing the clearance from being reduced by the grease applied to the 2 nd contact surface and the connecting member from extending to the exposed surface 122 and being difficult to observe, it is preferable to increase the clearance between the substrate 70 or the electronic component 80 and the exposed surface 122. Further, if the coil support member 60 is displaced in the upward direction, it becomes difficult to observe the lower end portion of the connection member, and therefore, it is preferable to leave a sufficient gap.

As the size of such a gap, for example, as shown in fig. 16, a dimension L1 between the exposed surface 122 of the heat sink 100 and the lower surface of the substrate 70 (or the electronic component) is larger than a dimension L2 from the substrate through hole 71 to the outer end of the pad 74.

Preferably, the angle θ formed by the virtual line T connecting the outer end of the pad 74 and the intersection of the coil line C and the exposed surface 122 is 45 degrees or more with the exposed surface 122.

As shown in fig. 1, when the tip of the member supporting the conductive member (coil supporting member 60 in the present embodiment) is at the same axial height as the exposed surface or is positioned below the exposed surface, the lower end of the connecting member can be more easily confirmed. On the other hand, when the axial height of the tip of the member supporting the conductive member is the same as the exposed surface 122 or is positioned above the exposed surface 122, the conductive member connecting the substrate 70 or the electronic component 80 and the conductive member can be further prevented from being electrically connected to the heat sink 100.

[ inner and outer regions ]

As shown in fig. 1, the heat sink 100 includes an inner region 130, an outer region 140 located radially outward of the inner region 130, and an outer wall portion 150 formed radially outward of the outer region 140.

The inner region 130 overlaps at least a part of the electronic component 80 in the axial direction. The thickness in the axial direction of the inner region 130 is greater than the thickness in the axial direction of the outer region 140.

In the present embodiment, since the heat sink through holes 110U, 110V, and 110W are located in the radially outer region of the substrate 70, the electronic components are densely packed in the radially inner region of the substrate 70. Therefore, by increasing the thickness of the inner region 130 of the heat sink 100 in the axial direction, the heat of the electronic component can be released to the heat sink 100. In addition, by reducing the thickness of the outer region 140, a space for accommodating components can be secured. This enables the electronic component to radiate heat more efficiently, and the size in the axial direction can be suppressed.

As shown in fig. 18, the inside area 130 has an inside wall portion 131 and ribs 132. The inner wall portion 131 and the ribs 132 are formed on the radiator lower surface 102. The inner wall portion 131 extends axially downward at a radially inner end. The rib 132 extends radially outward from the inner wall 131. A plurality of ribs 132 are provided, and the plurality of ribs 132 are arranged at equal intervals in the circumferential direction. The plurality of ribs 132 radially extend around the central axis a. Since the rigidity of the inner region 130 of the heat sink 100 can be increased by the inner wall portion 131 and the ribs 132, when the heat sink 100 holds the bearing 43, the durability against stress or the like for supporting the shaft 41 can be improved. Further, by extending the ribs 132 in the radial direction, the heat capacity of the heat sink 100 can be increased, and heat can be easily transferred to the outside in the radial direction.

The outer region 140 has the radiator through holes 110U, 110V, and 110W through which the coil wire C is inserted. The lower surface of the outer region 140 is located axially above the lower surface of the inner region 130.

As shown in fig. 1, the bus bar holding member 54 is located axially below the outer region 140 and overlaps the inner region 130 in the radial direction. In other words, a recess recessed upward in the axial direction is provided in the radially outer lower surface of the heat sink 100, and the bus bar B is accommodated in the recess.

In the present embodiment, a large number of heat generating elements (elements having a relatively large amount of heat generation such as FETs) are arranged in the center portion (radially inside) of the substrate 70. Therefore, the heat radiation effect is improved by increasing the thickness of the inner region 130 located at the center of the heat sink 100 facing the substrate 70.

On the other hand, a coil wire C drawn from the coil 53 of the stator 50 is connected to the outside (radially outside) of the substrate 70, and no heating element is disposed. By disposing the bus bar holding member 54 with a reduced thickness in the outer region 140, the height in the axial direction can be suppressed. In addition, since the heat sink 100 covers the upper surface and the side surface of the bus bar, the heat sink 100 can absorb the radiation heat of the bus bar during driving.

The outer side wall portion 150 surrounds the radially outer side of the bus bar holding member 54. The thickness of the outer side wall portion 150 in the axial direction is larger than the thickness of the inner side area 130 in the axial direction. At least a portion of the outer side wall portion 150 is exposed to the outside. Since the outer side wall portion 150 includes the portion of the heat sink 100 having the largest thickness in the axial direction, the heat radiation effect can be further improved.

[ positioning and fixing with substrate ]

As shown in fig. 17, a 2 nd positioning recess 176 is formed in the heat sink upper surface 101 of the heat sink main body 103 for positioning with the substrate 70. The 2 nd positioning recess 176 is a circular recess and is formed in plural. Positioning members such as positioning pins are inserted into the 2 nd positioning recess 176 of the heat sink 100 and the positioning hole 76 (see fig. 15) of the substrate 70 to perform positioning.

The heat sink main body 103 has a fixing hole 177 for fixing to the substrate 70. The fixing hole 177 is a substrate contact portion that contacts the substrate 70 in the axial direction. The fixing hole 177 is a circular hole and is formed in a plurality of numbers. Fixing members such as fixing pins and screws are inserted into the fixing holes 177 and 77 (see fig. 15) of the heat sink 100 to fix the substrate 70 and the heat sink 100.

As described above, the heat sink 100 and the substrate 70 are positioned using the positioning member, and then fixed using the fixing member. After the substrate 70 and the heat sink 100 are fixed, the positioning member is removed.

Further, since the heat sink 100 is in contact with the substrate 70, the fixing hole 177 protrudes upward in the axial direction with respect to the exposed surface 122. That is, in the present embodiment, the fixing hole 177 is located on the 1 st contact surface.

As shown in fig. 17, the plurality of heat sink through holes 110 and the fixing hole 177 are provided at intervals in the circumferential direction. The 2 fixing hole portions 177 are provided at intervals in the circumferential direction from the radiator through holes 110U, 110W located at both ends in the circumferential direction among the plurality of radiator through holes 110.

[ Structure for positioning with connector ]

As shown in fig. 18, in order to position the connector 200, the heat sink protrusion 104 is formed with a 1 st positioning hole 178 and a 1 st positioning concave portion 179 or a 1 st positioning convex portion (not shown). The 1 st positioning recess is a notch recess.

< connector >

As shown in fig. 1, the connector 200 is disposed adjacent to the housing 10, and electrically connects the substrate 70 and the outside of the motor 1. The connector 200 of the present embodiment is disposed radially outward of the housing 10 and extends axially downward (downward), and the connector 200 accommodates therein the connector pins 81 as conductive members extending axially downward from the substrate 70.

The top surface of the connector 200 is located below the heat sink top surface 101 of the heat sink 100, and the connector 200 overlaps the substrate 70 when viewed from the upper side in the axial direction.

[ Structure of connector ]

As shown in fig. 30 and 31, the connector 200 includes: a connector main body portion 210 extending in the axial direction; a connector flange portion 220 extending radially outward from an outer side surface of the connector body portion 210; and a connector protrusion 230 extending axially upward from the upper surface of the connector body 210.

As shown in fig. 32, when the hollow portion H is formed by the heat sink main body portion 103 and the 2 heat sink protruding portions 104, at least a part of the connector main body portion 210 is positioned in the hollow portion H.

The connector body 210 has a body protrusion 211 or a body recess (not shown) formed on an outer side surface and extending in the axial direction. The body protrusion 211 extends axially from the connector flange portion 220 to the connector protrusion 230.

As shown in fig. 6, 31, and the like, the connector body portion 210 also has a connector projection 215 formed in the radially outer end region and extending in the axial direction. The connector projection 215 is an outer edge portion including a radially outer connector outer edge 216. In addition, the connector outer end edge 216 refers to an outer end (end of the connector 200).

The connector body 210 further includes a cavity 217 formed by a radially inner surface of the connector projection 215 on a radially inner side of the connector projection 215. The cavity portion 217 stores dust entering from the outside.

The connector flange portion 220 is formed at the center portion in the axial direction of the connector body portion 210. The central portion is a predetermined range from the center (for example, within 1/3 axial height from the center of the axial height). This improves durability even when external force is applied to the connector 200.

As shown in fig. 30 and 31, a fitting portion 221 for positioning with the heat sink 100 is formed on the upper surface of the connector flange portion 220. The fitting portion 221 is fitted into the 1 st positioning hole 178 and the 1 st positioning concave portion 179 or the 1 st positioning convex portion (not shown), respectively. The fitting portion 221 of the present embodiment is a protrusion extending upward.

The connector protrusion 230 extends upward from the upper surface of the connector body 210. The connector protrusion 230 may be integrally formed with the connector body 210 or may be a separate member.

[ fitting of cover to connector ]

As shown in fig. 6, the connector projection 215 and the cover recess 33 are fitted with a gap therebetween. The connector 200 is substantially rectangular in plan view. The connector convex portion 215 and the cover concave portion 33 extend along the length direction of the connector 200.

As shown in fig. 1, the connector protrusion 230 is fitted to the cover step 35 with a gap therebetween. The radially outer corner of the connector protrusion 230 is fitted so as to face the stepped portion of the cover stepped portion 35.

The fitting between the cover 30 and the connector 200 in the outer end region R of the present embodiment is described by way of example with reference to the structure shown in fig. 6, but may be configured as shown in fig. 7 to 9.

In the configuration shown in fig. 7, the connector projection 215 is not constituted by the connector outer end edge 216, but extends axially upward from a position spaced apart from the connector outer end edge 216 in the radial direction. The fitting of the connector convex portion 215 and the cover concave portion 33 with a gap is located in the outer end region R excluding the cover outer end edge 31 and the connector outer end edge 216.

In the configuration shown in fig. 8, the connector 200 further includes a step portion 218 extending radially inward from an upper end of a radially inner surface of the cavity portion 217. The connector convex portion 215 is fitted with the hood concave portion 33 with a gap therebetween, and the concave portion 219 including the cavity portion 217 and the stepped portion 218 is fitted with the hood convex portion 34 with a gap therebetween.

In the configuration shown in fig. 9, the connector 200 has a cavity 217 formed by a radially outer surface of the connector projection 215 on a radially outer side of the connector projection 215. Part of the cover concave portion 33 faces the cavity portion 217, and the remaining portion of the cover concave portion 33 is fitted to the connector convex portion 215 with a gap therebetween. The fitting of the connector convex portion 215 and the cover concave portion 33 with a gap is located in the outer end region R not including the cover outer end edge 31 and the connector outer end edge 216.

As described above, the motor 1 of the present embodiment has a labyrinth structure in which the cover 30 and the connector 200 are fitted to each other with a gap therebetween in accordance with the shape of the projections and the recesses of each other. Therefore, the dust-proof effect is provided, and the motor can be easily assembled.

[ contact between connector and radiator ]

As shown in fig. 32, the connector 200 is in contact with the lower surface of the heat sink protrusion 104. Specifically, the heat sink protrusion 104 is disposed on the connector flange portion 220 such that the flange upper surface 222 of the connector flange portion 220 contacts the heat sink lower surface 102 of the heat sink protrusion 104. As shown in fig. 17, when the plurality of heat sink protruding portions 104 are formed at intervals, the connector flange portion 220 contacts the lower surfaces of the plurality of heat sink protruding portions 104.

The connector flange portion 220 may include a metal collar or the like positioned at the upper end. In the case where the connector flange portion 220 includes a metal collar, the metal collar is in contact with the lower surface of the heat sink protrusion 104.

[ fitting of connector and Heat sink ]

The body convex portion 211 and the heat sink concave portion 105 are fitted with a gap therebetween. Alternatively, instead of the main body convex portions 211, main body concave portions may be formed, and instead of the heat sink concave portions, heat sink convex portions may be formed, and the main body concave portions and the heat sink convex portions may be fitted with gaps therebetween. Thus, when connector 200 and heat sink 100 are fitted to each other with a gap between the concave and convex shapes, the assembly is easy.

The main body convex portion or the main body concave portion and the heat sink concave portion or the heat sink convex portion, which are fitted to each other with a gap therebetween, extend in the axial direction.

[ positioning of connector and Heat sink ]

The heat sink 100 and the connector 200 are positioned by the connector fitting portion 221 being fitted into the 1 st positioning hole 178 (see fig. 17 and 18) and the 1 st positioning concave portion 179 (see fig. 18) or the 1 st positioning convex portion (not shown) of the heat sink 100. In the present embodiment, a protrusion serving as a fitting portion 221 provided on the upper surface of the connector flange portion 220 is fitted into a circular hole serving as the 1 st positioning hole 178 and a cutout recess serving as the 1 st positioning recess 179 of the heat sink protruding portion 104.

The shape of the heat sink 100 and the connector 200 is not limited as long as they are fitted to each other.

< modification example >

[ fixation based on the cover ]

As described above, in the present embodiment, the structure in which the cover 30 and the connector 200 are fixed to the heat sink 100 is described as an example, but the motor of the present invention may be a structure in which the heat sink and the connector are fixed to the cover. In the latter case, a structure in which the heat sink and the connector are fitted with a gap therebetween can be adopted, thereby achieving a structure that is easy to assemble.

[ Motor main body and control Unit ]

In the present embodiment, an example of an electromechanical motor in which a motor main body portion including a rotor and a stator and a control portion for controlling the motor main body portion are integrally arranged is described, but the motor of the present invention is not limited to the electromechanical motor.

[ function of radiator ]

In the present embodiment, the structure in which the heat sink 100 also serves as a holder for holding the bearing 43 has been described as an example, but the heat sink of the present invention may be separate from the bearing holder.

The heat sink 100 of the present embodiment is described as an example of a structure serving as a holder for holding the coil support member 60 inserted into the heat sink through hole 110. However, the heat sink of the present invention may have no function of holding the coil support member as long as the heat sink has a through hole through which the coil support member is inserted into the heat sink through hole.

< Effect >

As described above, the motor according to embodiment 1 of the present invention includes: a rotor including a shaft extending in an axial direction; a stator surrounding a radial outer side of the rotor and including a coil formed by winding a coil wire; a coil support member made of an insulating material, disposed on an upper side in an axial direction of the stator, and through which the coil wire is inserted; a heat sink which is disposed on the upper side in the axial direction of the stator and has a through hole through which the coil support member is inserted; and a substrate arranged on an axially upper side of the heat sink and having an electronic component mounted thereon, wherein the heat sink is provided with a recess located at an upper end portion of the through hole, a bottom surface of the recess is exposed when viewed from the axially upper side, and an axial position of an upper surface of the coil support member is different from an axial position of the bottom surface of the recess.

According to the motor of embodiment 1 of the present invention, since the recess can form a gap between the heat sink and the connection member that connects the coil wire and the substrate, the connection member can be insulated from the heat sink. Further, since the recess is formed in the upper end portion, a reduction in the capacity of the heat sink can be suppressed, and thus the heat dissipation performance of the electronic component can be maintained. In this way, in the heat sink, the following design can be made: in a state where insulation from the connection member is achieved and a region for heat dissipation is secured, the height in the axial direction is suppressed.

Further, since the axial positions of the upper surface of the coil support member and the bottom surface of the recess are different, even if the heat dissipation member enters the through hole from the upper surface side of the heat sink, the heat dissipation member can be prevented from moving toward the lower surface side of the through hole by the two steps of the coil support member and the recess. Since the stator is disposed axially below the lower surface of the through hole, the heat radiating member can be prevented from entering the stator.

As described above, the motor according to embodiment 1 of the present invention can reduce the axial dimension and prevent the heat dissipation member from entering the stator.

In the motor according to embodiment 1 of the present invention, it is preferable that the coil support member includes: a protrusion part for inserting the coil wire therethrough; and a base portion that is located axially below the protrusion portion, extends in the radial direction, and at least a part of the base portion overlaps the through hole when viewed in the axial direction.

Thus, even if a gap is left between the protrusion of the coil support member and the through hole of the heat sink, the base of the coil support member can prevent the heat dissipation member from entering the stator.

In the motor according to embodiment 1 of the present invention, it is preferable that the upper surface of the coil support member is positioned axially above the bottom surface of the recess.

Thus, even if the heat dissipation member enters the through hole, the side surface of the coil support member in the recess and the side surface and the bottom surface of the recess can function as a cavity for accommodating the heat dissipation member. Therefore, the heat dissipation member can be further prevented from entering the stator.

In the motor according to embodiment 1 of the present invention, it is preferable that the recess is formed by a heat sink upper surface, a side surface extending downward from the heat sink upper surface, and a bottom surface continuous to a lower end of the side surface, and an intersection angle between the side surface and the bottom surface of the through hole is 90 degrees or less.

Since the angle of intersection between the side surface of the through hole and the bottom surface of the recess is 90 degrees or less, the heat dissipation member can be easily housed in the recess even if the heat dissipation member enters the through hole. Therefore, the heat dissipation member can be further prevented from entering the stator.

In the motor according to embodiment 1 of the present invention, it is preferable that the recess is formed by a heat sink upper surface, a side surface extending downward from the heat sink upper surface, and a bottom surface continuous to a lower end of the side surface, and the heat sink upper surface is parallel to the bottom surface.

In this case, since the processing is easy, the motor can be easily realized in which the dimension in the axial direction is reduced and the heat dissipation member is prevented from entering the inside of the stator.

In the motor according to embodiment 1 of the present invention, it is preferable that the upper end portion of the coil support member has a tapered portion whose width is narrowed toward the upper side in the axial direction.

The space as a cavity for accommodating the heat dissipation member can be formed by the side surface of the tapered portion of the coil support member and the side surface of the through hole or the recess. Therefore, the heat dissipation member can be further prevented from entering the stator.

In the motor according to embodiment 1 of the present invention, it is preferable that the lower end of the tapered portion is located axially below the bottom surface of the recess.

Thus, a space as a cavity for accommodating the heat dissipation member can be formed by the side surface of the tapered portion and the side surface of the through hole, which are located axially below the bottom surface of the recess. Therefore, the heat dissipation member can be more effectively prevented from entering the stator.

In the motor according to embodiment 1 of the present invention, it is preferable that the upper end of the tapered portion is located axially above the bottom surface of the recess.

Thus, the space as the cavity for accommodating the heat dissipation member can be formed by the side surface of the tapered portion located axially above the bottom surface of the recess and the recess. Therefore, the heat dissipation member can be effectively prevented from entering the stator.

(embodiment mode 2)

An embodiment of an apparatus including the motor 1 according to embodiment 1 will be described with reference to fig. 33. In embodiment 2, an example in which the motor 1 is mounted on an electric power steering apparatus will be described.

The electric power steering apparatus 2 is mounted on a steering mechanism of a wheel of an automobile. The electric power steering apparatus 2 of the present embodiment is a column type power steering apparatus that directly reduces steering force by the power of the motor 1. The electric power steering apparatus 2 includes a motor 1, a steering shaft 914, and an axle 913.

The steering shaft 914 transmits an input from a steering wheel 911 to an axle 913 having wheels 912. The power of the motor 1 is transmitted to the axle 913 through the ball screw. The motor 1 employed in the column electric power steering apparatus 2 is disposed inside an engine room (not shown). In the case of the column power steering apparatus, since the waterproof structure can be provided for the engine room itself, it is not necessary to provide the waterproof structure for the motor itself. On the other hand, although dust may enter the engine room, the motor 1 has a dustproof structure, and therefore, entry of dust into the motor main body can be suppressed.

The electric power steering apparatus 2 according to embodiment 2 includes the motor 1 according to embodiment 1. Therefore, the electric power steering device 2 that achieves the same effects as those of embodiment 1 is obtained. That is, the electric power steering apparatus 2 according to embodiment 2 includes the motor according to embodiment 1, and therefore, the dimension in the axial direction can be reduced and the heat dissipation member can be prevented from entering the stator.

Here, the electric power steering apparatus 2 is described as an example of a method of using the motor 1 according to embodiment 1, but the method of using the motor 1 is not limited, and can be applied to a wide range of pumps, compressors, and the like.

The embodiments disclosed herein are illustrative in all respects and should not be construed as being limiting. The scope of the present invention is defined not by the embodiments described above but by the appended claims, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.

Description of the reference symbols

1: a motor; 2: an electric power steering apparatus; 10: a housing; 11: a 1 st cylinder part; 12: a contact portion; 12 a: a lower surface of the housing; 13: a 2 nd cylindrical part; 13 a: an upper side cylinder part; 13 b: a lower side cylinder part; 13 c: a connecting portion; 14: a bottom; 20: a flange; 21: a flange cylindrical portion; 21 a: an upper end; 22: a flange plane portion; 23: a fixing hole portion; 30: a cover; 30 a: a disk-shaped portion; 30 b: a rectangular-shaped portion; 31: the outer end edge of the cover; 32: a cladding wall; 33: a cover recess; 34: a cover convex portion; 35: a cover step portion; 40: a rotor; 41: a shaft; 42: a rotor core; 43: a bearing; 44: a bearing; 50: a stator; 51: a stator core; 51 b: teeth; 52: an insulating member; 53: a coil; 53U1, 53U2, 53V1, 53V2, 53W1, 53W 2: an outgoing line; 53 a: overlapping wires; 54: a bus bar holding member; 55. 61: a base; 56: a holding section; 57: a bus bar protrusion; 60: a coil support member; 60 a: an upper surface; 60 b: a tapered portion; 61b 1: a lower end; 62: a coil support portion; 62 a: a protrusion portion; 63: cutting; 64: a groove part; 65: a through hole; 66. 132: a rib; 67: a coil support member fitting portion; 70: a substrate; 71. 72: a substrate through-hole; 73: a printing plate; 74: a pad; 75: a connecting member; 76: a positioning hole portion; 77: a fixing hole portion; 80: an electronic component; 81: a connector pin; 100: a heat sink; 101: an upper surface of the heat sink; 102: a lower surface of the heat sink; 103: a radiator main body portion; 104: a heat sink protrusion; 105: a heat sink recess; 110. 110U, 110V, 110W: a radiator through hole; 110 a: a through hole side surface; 111: a recess; 112: a recess side surface; 113: a recess bottom surface; 121: a contact surface; 122: an exposed surface; 123: a heat dissipating member; 130: an inner region; 131: an inner wall portion; 140: an outer region; 150: an outer side wall portion; 176: a 2 nd positioning recess; 177: a fixing hole portion; 178: 1, positioning holes; 179: 1 st positioning recess; 200: a connector; 222: a flange upper surface; 210: a connector main body portion; 211: a body projection; 215: a connector boss; 216: an outer connector end edge; 217: a cavity portion; 218: a step portion; 219: a recess; 220: a connector flange portion; 221: a fitting portion; 230: a connector projection; 911: a steering wheel; 912. 913: a wheel; 914: a steering shaft; a: a central axis; b: a bus bar; c: a coil wire; d1, D2: a crossing angle; g: a ground line; h: a hollow portion; l1, L2: size; m, N: an arrow; p: a pin; r: an outer end region; s1: region 1; s2: a 2 nd region; t: an imaginary line; α: a center angle; θ: and (4) an angle.

Claims (9)

1. A motor, comprising:

a rotor including a shaft extending in an axial direction;

a stator surrounding a radial outer side of the rotor and including a coil formed by winding a coil wire;

a coil support member made of an insulating material, disposed on an upper side in an axial direction of the stator, and through which the coil wire is inserted;

a heat sink disposed on an upper side in an axial direction of the stator, the heat sink having a through hole through which the coil support member is inserted; and

a substrate disposed on an upper side in an axial direction of the heat sink and mounted with an electronic component,

the heat sink is provided with a recess portion which is located at an upper end portion of the through hole and has a bottom surface exposed when viewed from an axially upper side,

an upper surface of the coil support member is different in axial position from the bottom surface of the recess,

the heat sink has:

a contact surface that is in contact with the substrate or the electronic component directly or through a heat dissipation member; and

an exposed surface exposed without contacting with other parts,

the exposed surface is located closer to the outer edge than the through hole,

the exposure surface is located axially lower than the contact surface,

the upper surface of the coil support member is at the same axial height as the exposed surface or is located above the exposed surface.

2. The motor of claim 1,

the coil support member includes:

a protrusion through which the coil wire is inserted; and

a base portion located axially below the projection portion and extending in a radial direction,

at least a portion of the base overlaps the through hole when viewed in the axial direction.

3. The motor according to claim 1 or 2,

an upper surface of the coil support member is positioned axially above the bottom surface of the recess.

4. The motor according to claim 1 or 2,

the recess is composed of a radiator upper surface, a side surface extending downward from the radiator upper surface, and the bottom surface connected to the lower end of the side surface,

the crossing angle between the side surface of the through hole and the bottom surface is 90 degrees or less.

5. The motor according to claim 1 or 2,

the recess is composed of a radiator upper surface, a side surface extending downward from the radiator upper surface, and the bottom surface connected to the lower end of the side surface,

the upper surface of the radiator is parallel to the bottom surface.

6. The motor according to claim 1 or 2,

the upper end portion of the coil support member has a tapered portion whose width becomes narrower toward the upper side in the axial direction.

7. The motor of claim 6,

the lower end of the tapered portion is located axially below the bottom surface of the recess.

8. The motor of claim 6,

an upper end of the tapered portion is located axially above the bottom surface of the recess.

9. An electric power steering apparatus having the motor of any one of claims 1 to 8.

Images