Motor unit

Abstract

A control device (3) of a motor unit (1) comprises an external connector (42), a first substrate (43), a second substrate (44), and a circuit component (46). The external connector (42) has a base section (61), and a positioning pin (65) that protrudes from the base section (61) toward a motor (2). The first substrate (43) has a first through-hole (71), and the second substrate (44) has a second through-hole (72) that is provided in a location corresponding to the first through-hole (71). The same positioning pin (65) is inserted into the first through-hole (71) and the second through-hole (72).

Description

[Technical Field]

[0001] The present disclosure relates to a motor unit. [Background technology]

[0002] Conventionally, there are motor units in which a control device that controls the operation of a motor is integrated with the motor. Such a motor unit control device includes a power board, a control board, and an external connector to which external wiring is connected, as described in Patent Document 1, for example. In this control device, the power board is directly fixed to the heat sink of the motor. Meanwhile, the control board is fixed to the external connector, which is fixed to the heat sink. In other words, the control board is fixed to the heat sink via the external connector. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-65018 Summary of the Invention [Problem to be solved by the invention]

[0004] In the control device of Patent Document 1, the relative position between the power board and the heat sink varies within the range of tolerances, for example, during manufacturing and assembly. Similarly, the relative positions between the control board and the external connector, and between the external connector and the heat sink also vary within their respective tolerance ranges. Therefore, when these tolerances are combined, there is a risk that the variation in the relative positions between the power board and the control board will increase. [Means for solving the problem]

[0005] One aspect of the present disclosure provides a motor unit. The motor unit includes a motor and a control device configured to control the motor. The control device includes an external connector arranged along the axis of the motor with a gap between it and the motor, a first board arranged between the motor and the external connector in a position intersecting the axis of the motor, a second board arranged alongside the first board between the first board and the external connector, and circuit components mounted on the first board and the second board. The external connector has a base portion and a positioning pin protruding from the base portion toward the motor. The first board has a first through hole, and the second board has a second through hole provided at a position corresponding to the first through hole. The common positioning pin is inserted into the first through hole and the second through hole. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 2 is a perspective view of the motor unit according to the embodiment. [Figure 2] 2 is a partial cross-sectional view of the vicinity of the control device in the motor unit of FIG. 1. [Figure 3] FIG. 2 is an exploded perspective view of the motor unit of FIG. 1. [Figure 4] FIG. 10 is an enlarged cross-sectional view of the vicinity of a positioning pin of an external connector in a motor unit according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0007] An embodiment of a motor unit will be described below with reference to the drawings. 1 and 2, the motor unit 1 includes a motor 2 and a control device 3 that controls the operation of the motor 2. The control device 3 is fixed to one axial end of the motor 2. In the following description, the side of the motor 2 on which the control device 3 is located will be referred to as the first side, and the opposite side will be referred to as the second side.

[0008] (Motor 2) The motor 2 is, for example, a three-phase brushless motor. The motor 2 includes a cylindrical housing 11, a stator 12 fixed inside the housing 11, a rotor 13 rotatably disposed on the inner periphery of the stator 12, and a heat sink 14.

[0009] In this specification, "cylindrical" means that the entire product can be considered cylindrical, and includes products formed by combining multiple parts and products with a partial cutout such as a C-shape. "Cylindrical" shapes include, but are not limited to, circular, elliptical, and polygonal shapes with sharp or rounded corners when viewed in the axial direction.

[0010] As shown in Fig. 2, the stator 12 includes a stator core 21 and a plurality of coil groups 22. The stator core 21 is fixed to the inner periphery of the housing 11. Each coil group 22 has three-phase motor coils of U, V, and W, which are wound around the teeth of the stator core 21. Each coil group 22 is configured to receive drive power independently from the control device 3. In other words, the motor 2 has a redundant configuration with respect to the motor coils.

[0011] The rotor 13 includes a rotating shaft 23, a rotor core 24, a rotor magnet 25, and a sensor magnet 26. The rotating shaft 23 is rotatably supported by bearings 27 provided in the heat sink 14. In other words, the heat sink 14 is used as a bearing holder. The heat sink 14 may also be referred to as a bearing holder. The rotor core 24 is fixed to the outer periphery of the rotating shaft 23. The rotor magnet 25 is fixed to the outer periphery of the rotor core 24, for example. The sensor magnet 26 is fixed to a first side end of the rotating shaft 23.

[0012] In the motor 2 configured in this manner, a rotating magnetic field is generated in the stator 12 when drive power is supplied from the control device 3 to each coil group 22, and the rotor 13 rotates in response to this rotating magnetic field.

[0013] (heat sink 14) Next, the configuration of the heat sink 14 will be described in detail. 2 and 3, the heat sink 14 is made of a metal material such as an aluminum alloy. The heat sink 14 is plate-shaped and covers the opening on the first side of the housing 11. As shown in the figures, the heat sink 14 has, for example, a substantially rectangular shape when viewed in the axial direction of the motor 2. The heat sink 14 is disposed within the first side end of the housing 11. The heat sink 14 is rigidly fixed to the housing 11 by, for example, screws (not shown).

[0014] The heat sink 14 has a raised portion 31 and a sunken portion 32 that is sunken toward the second side relative to the raised portion 31. That is, the sunken portion 32 is sunken so as to move away from the external connector 42 (described later). In other words, the raised portion 31 is raised toward the first side relative to the sunken portion 32. As a result, the heat sink 14 has a stepped plate shape. The thickness of the raised portion 31 along the axis L of the motor 2 is greater than the thickness of the sunken portion 32 along the axis L. In this embodiment, the heat sink 14 is divided into two regions by a line perpendicular to the axis L of the motor 2, and one of the regions is the sunken portion 32, and the other is the raised portion 31. As a result, each of the sunken portion 32 and the raised portion 31 has a substantially rectangular shape when viewed in the axial direction of the motor 2. In other embodiments, for example, the sunken portion 32 may be L-shaped when viewed in the axial direction of the motor 2, and the shapes of the sunken portion 32 and the raised portion 31 can be changed as appropriate.

[0015] The heat sink 14 has a holding hole 33. The holding hole 33 penetrates the heat sink 14 along the axis L of the motor 2. The bearing 27 is provided on the inner periphery of the holding hole 33.

[0016] 3, the heat sink 14 has one or more support protrusions 34 that protrude from the sunken portion 32 to the first side. The heat sink 14 has, for example, two support protrusions 34. The support protrusions 34 are, for example, cylindrical. The height of the support protrusions 34 from the sunken portion 32 is approximately equal to the height of the raised portion 31 from the sunken portion 32. The support protrusions 34 are provided, for example, at corners of the sunken portion 32.

[0017] The heat sink 14 has one or more screw holes 35 that open to the first side. The heat sink 14 has, for example, four screw holes 35. The screw holes 35 are provided in each of the support protrusions 34 and the raised portion 31.

[0018] 2, the heat sink 14 has one or more positioning holes 36 that open to the first side. The heat sink 14 has, for example, two positioning holes 36. The positioning holes 36 are provided, for example, on the edge of the sinking portion 32. The inner circumferential surface of the positioning hole 36 has a smooth cylindrical shape.

[0019] (Control device 3) The control device 3 includes a cover 41, an external connector 42, a first board 43, a second board 44, a pair of board-to-board connectors 45, and various circuit components 46. Wiring extending from outside the motor unit 1 is connected to the external connector 42. The external connector 42 supports the first board 43 and the second board 44. The pair of board-to-board connectors 45 electrically connect the first board 43 and the second board 44 to each other. The various circuit components 46 are mounted on the first board 43 and the second board 44. Mounting the various circuit components 46 in predetermined positions on the first board 43 and the second board 44 configures a drive circuit that supplies drive power to the motor 2 and a control circuit that controls the operation of the drive circuit. For ease of explanation, the cover 41 is not shown in FIG. 3.

[0020] The control device 3 of this embodiment has the same number of drive circuits and control circuits as the number of coil groups 22, corresponding to the fact that the stator 12 has a plurality of coil groups 22. In other words, the control device 3 has a configuration in which the power supply system and control system for the coil groups 22 are made redundant.

[0021] In the control device 3 configured in this manner, the drive circuit operates based on the control signal output from the control circuit, and supplies drive power to the motor 2. Each component of the control device 3 will be described in detail below.

[0022] (Cover 41) 1 and 2, the cover 41 is cylindrical. The cover 41 has an end wall 51 provided at a first side end thereof. The end wall 51 has an opening 52 that penetrates in the axial direction. The cover 41 is fixed to the housing 11 by fitting a second side end of the cover 41 into the first side end of the housing 11. As a result, the cover 41 covers the opening on the first side of the housing 11 so that the first board 43, the second board 44, etc. are not exposed. The opening 52 is closed by the external connector 42.

[0023] (External Connector 42) 2 and 3, the external connector 42 includes a base portion 61, one or more socket portions 62, one or more first board support posts 63, one or more second board support posts 64, and one or more positioning pins 65.

[0024] The base portion 61 is shaped like a flat plate that covers the entire opening 52 of the cover 41. The external connector 42 is provided with, for example, five socket portions 62. The socket portions 62 protrude from the base portion 61 through the opening 52 to the first side, i.e., to the outside of the cover 41. The socket portions 62 are configured so that corresponding external wiring can be inserted into them. Connection terminals provided within the socket portions 62 are connected to predetermined positions on the second board 44.

[0025] The external connector 42 is provided with, for example, two first board support posts 63. The first board support posts 63 protrude from the base portion 61 to the second side, i.e., toward the motor 2. The first board support posts 63 are, for example, cylindrical. The first board support posts 63 have a first screw hole 66 opening at the tip. The first board support posts 63 are provided on, for example, the edge portion of the base portion 61.

[0026] The external connector 42 is provided with, for example, three second board supports 64. The second board supports 64 protrude from the base portion 61 to the second side, i.e., toward the motor 2. The second board supports 64 are, for example, cylindrical. The second board supports 64 have second screw holes 67 opening at their tips. The second board supports 64 are provided, for example, on the edge of the base portion 61. The amount by which the second board supports 64 protrude toward the second side is smaller than the amount by which the first board supports 63 protrude toward the second side. In other words, the first board supports 63 protrude farther toward the motor 2 than the second board supports 64.

[0027] The external connector 42 is provided with, for example, two positioning pins 65. The positioning pins 65 protrude from the base portion 61 toward the second side, i.e., toward the motor 2. The positioning pins 65 are, for example, cylindrical. The positioning pins 65 protrude toward the motor 2 farther than the first board support columns 63 and the second board support columns 64. The positioning pins 65 have a large diameter portion 68 and a small diameter portion 69 having an outer diameter smaller than that of the large diameter portion 68. The small diameter portion 69 is provided contiguous to the second side of the large diameter portion 68. The outer peripheral surface of the tip of the small diameter portion 69, i.e., the tip of the positioning pin 65, is smooth and cylindrical.

[0028] (First substrate 43 and second substrate 44) The first substrate 43 and the second substrate 44 are both flat. When viewed in the axial direction of the motor 2, the first substrate 43 has approximately the same size as the recessed portion 32 of the heat sink 14. When viewed in the axial direction of the motor 2, the second substrate 44 has approximately the same size as the entire heat sink 14. The first substrate 43 is disposed between the heat sink 14 of the motor 2 and the external connector 42, in a position perpendicular to the axis L of the motor 2. The second substrate 44 is disposed between the first substrate 43 and the external connector 42, in a position perpendicular to the axis L of the motor 2. In other words, the second substrate 44 is disposed parallel to the first substrate 43. As a result, the first substrate 43, the second substrate 44, and the external connector 42 are lined up on the first side from the heat sink 14 in the order of the first substrate 43, the second substrate 44, and the external connector 42.

[0029] The first substrate 43 has first through holes 71, the number of which is the same as the positioning holes 36. The first through holes 71 are provided at positions opposing the positioning holes 36 in the axial direction of the motor 2. The second substrate 44 has second through holes 72, the number of which is the same as the positioning holes 36. The second through holes 72 are provided at positions opposing the positioning holes 36 and the first through holes 71 in the axial direction of the motor 2. In other words, the positioning holes 36, the first through holes 71, and the second through holes 72 are arranged on a straight line parallel to the axis L of the motor 2.

[0030] In this specification, "facing" refers to surfaces or components facing each other, and includes not only cases where they are completely facing each other, but also cases where they are partially facing each other. In addition, in this specification, "facing" can include both cases where a component separate from the two components is interposed between the two components, and cases where nothing is interposed between the two components. In addition, in this specification, "facing" can include both cases where the two opposing components are in contact with each other, and cases where there is a gap between them.

[0031] A common positioning pin 65 is inserted into the second through-hole 72, the first through-hole 71, and the positioning hole 36. That is, the first substrate 43, the second substrate 44, and the heat sink 14 are positioned relative to the external connector 42 by the common positioning pin 65.

[0032] Specifically, the positioning pin 65 is inserted into the second through hole 72, and the portion of the positioning pin 65 that protrudes from the second through hole 72 to the second side is inserted into the first through hole 71. The portion of the positioning pin 65 that protrudes from the first through hole 71 to the second side is inserted into the positioning hole 36. The large diameter portion 68 of the positioning pin 65 faces the second substrate 44 with a gap between them along the axis L. In other words, the large diameter portion 68 does not abut against the second substrate 44 from the first side.

[0033] The first substrate 43 is fixed to the first substrate support 63. Specifically, the first substrate 43 has a first insertion hole 43a at a position facing the first screw hole 66 of the first substrate support 63. The first substrate 43 is fixed to the tip of the first substrate support 63 by threading a first screw 73 into the first screw hole 66 through the first insertion hole 43a. The first substrate 43 is disposed on the first side of the sinking portion 32.

[0034] A heat dissipation material 74 is interposed between the first substrate 43 and the sinking portion 32. The heat dissipation material 74 is, for example, heat dissipation grease. This allows heat generated by the circuit components 46 mounted on the first substrate 43 to be dissipated to the heat sink 14. Hereinafter, the surface of the first substrate 43 facing the sinking portion 32 will be referred to as the back surface, and the opposite surface will be referred to as the front surface.

[0035] The second substrate 44 is fixed to the second substrate support 64. The second substrate 44 is also fixed to the heat sink 14. Specifically, the second substrate 44 has a second insertion hole 44a at a position facing the second screw hole 67 of the second substrate support 64. The second substrate 44 also has a second insertion hole 44b at a position facing the screw hole 35 of the heat sink 14 in the axial direction. The second substrate 44 is fixed to the tip of the second substrate support 64 by screwing a second screw 75 into the second screw hole 67 through the second insertion hole 44a. The second substrate 44 is also rigidly fixed to the first side of the heat sink 14 by screwing a fixing screw 76 into the screw hole 35 through the second insertion hole 44a. As a result, the second substrate 44 covers the first substrate 43 from the first side. The second substrate 44 has a notch 77 at a position corresponding to the first substrate support column 63 to avoid interference with the first substrate support column 63.

[0036] A heat dissipation material 78 is interposed between the second substrate 44 and the raised portion 31. The heat dissipation material 78 is, for example, heat dissipation grease. This allows heat generated by the circuit components 46 mounted on the second substrate 44 to be dissipated to the heat sink 14. Hereinafter, the surface of the second substrate 44 facing the raised portion 31 will be referred to as the back surface, and the opposite surface will be referred to as the front surface.

[0037] As described above, the external connector 42 is only indirectly fixed to the heat sink 14 via the second substrate 44, and is not directly fixed thereto. Also, the first substrate 43 is only indirectly fixed to the heat sink 14 via the external connector 42 and the second substrate 44, and is not directly fixed thereto. Furthermore, no heat sink is provided in the space between the first substrate 43 and the second substrate 44. This space is used to accommodate the circuit components 46 mounted on the first substrate 43 and the second substrate 44.

[0038] (Board-to-board connector pair 45) The inter-board connector pair 45 includes a first connector 81 mounted on the first board 43 and a second connector 82 mounted on the second board 44. The first connector 81 is mated with the second connector 82, thereby electrically connecting the first board 43 to the second board 44. As a result, the circuit components 46 mounted on the first board 43 exchange signals with the circuit components 46 mounted on the second board 44 via the inter-board connector pair 45.

[0039] The second connector 82 is configured to be displaceable relative to the first connector 81 in an orthogonal direction perpendicular to the axial direction of the motor 2. In other words, the board-to-board connector pair 45 is a floating type connector pair that allows displacement in the orthogonal direction between the first connector 81 and the second connector 82. The board-to-board connector pair 45 of this embodiment has a relatively small floating amount, which is the amount of allowable displacement in the orthogonal direction.

[0040] (Circuit component 46) The circuit component 46 includes a magnetic sensor 91 that detects the magnetic flux of a sensor magnet 26 fixed to the rotation shaft 23 of the rotor 13. The magnetic sensor 91 is mounted on the back surface of the second substrate 44 so as to face the sensor magnet 26 in the axial direction.

[0041] The circuit components 46 also include drive circuit components 92 that constitute the drive circuit and control circuit components 93 that constitute the control circuit. The drive circuit components 92 include a plurality of switching elements, such as FETs and IGBTs. The drive circuit components 92 are mounted in an area of ​​the second substrate 44 facing the raised portion 31. The drive circuit components 92 are mounted, for example, on the front surface of the second substrate 44, but may also be mounted on the back surface. The control circuit components 93 include, for example, a microcomputer. The control circuit components 93 control the operation of the drive circuit by outputting control signals that switch the on / off states of the switching elements. The control circuit components 93 are mounted on the first substrate 43. The control circuit components 93 are mounted, for example, on the front surface of the first substrate 43, but may also be mounted on the back surface.

[0042] Furthermore, the circuit components 46 include a large, heavy component 94 that is larger and heavier than the other circuit components. The large, heavy component 94 includes, for example, a capacitor and a coil for smoothing the driving power supplied from the power supply. The large, heavy component 94 is mounted in an area facing the protruding portion 31 on the second substrate 44. The large, heavy component 94 is mounted on, for example, the front surface of the second substrate 44, but may also be mounted on the back surface.

[0043] The circuit components 46 also include lightweight, low-heat-generating components 95 that are smaller and generate less heat than the other circuit components. The lightweight, low-heat-generating components 95 include, for example, a pre-driver for boosting the voltage of the control signal to a voltage suitable for operating the switching element, and a power supply IC for generating a drive voltage to drive the microcomputer. The lightweight, low-heat-generating components 95 may also include an IC for a communication network. The lightweight, low-heat-generating components 95 are mainly mounted in an area facing the sunken portion 32 on the second substrate 44. The lightweight, low-heat-generating components 95 are mounted on, for example, the front surface of the second substrate 44, but may also be mounted on the back surface. The lightweight, low-heat-generating components 95 are also mounted in areas facing the raised portion 31 on the first substrate 43 and the second substrate 44.

[0044] Next, the operation and effects of this embodiment will be described. (1) The control device 3 includes an external connector 42 arranged along the axis L of the motor 2 with a gap between it and the motor 2, and a first board 43 and a second board 44 arranged between the motor 2 and the external connector 42 in an orientation perpendicular to the axis L of the motor 2. The external connector 42 has a base portion 61 and a positioning pin 65 protruding from the base portion 61 toward the motor 2. The first board 43 has a first through hole 71, and the second board 44 has a second through hole 72 provided at a position corresponding to the first through hole 71. A common positioning pin 65 is inserted into the first through hole 71 and the second through hole 72.

[0045] According to the above configuration, second substrate 44 is positioned relative to external connector 42 by positioning pins 65, and first substrate 43 is positioned relative to external connector 42 by positioning pins 65 that position second substrate 44. Therefore, it is possible to prevent the variation in the relative positions of first substrate 43 and second substrate 44 from increasing compared to when, for example, first substrate 43 is positioned relative to external connector 42 via another member.

[0046] (2) The control device 3 further includes a board-to-board connector pair 45 including a first connector 81 mounted on the first board 43 and a second connector 82 mounted on the second board 44 and connected to the first connector 81. Therefore, the board-to-board connector pair 45 can easily electrically connect the first board 43 and the second board 44 to each other.

[0047] Here, if there is a large variation in the relative position between the first substrate 43 and the second substrate 44, it is necessary to use a board-to-board connector pair 45 with a large amount of floating. In this regard, in the present embodiment, a common positioning pin 65 is inserted into the first through hole 71 and the second through hole 72, thereby suppressing variation in the relative position between the first substrate 43 and the second substrate 44. Therefore, it is possible to adopt a board-to-board connector pair 45 with a relatively small amount of floating. This makes it possible to reduce the size of the first substrate 43 and the second substrate 44, and ultimately the size of the motor unit 1. In this way, applying a configuration in which a common positioning pin 65 is inserted into the first through hole 71 and the second through hole 72 to a motor unit 1 having a board-to-board connector pair 45 is highly effective.

[0048] (3) The motor 2 includes a heat sink 14 made of a metal material. The heat sink 14 has a raised portion 31 and a sunken portion 32 that is sunken so as to be farther away from the external connector 42 than the raised portion 31. The second substrate 44 is disposed on a first side of the raised portion 31 so as to cover a portion of the sunken portion 32. The first substrate 43 is disposed between the sunken portion 32 and the second substrate 44. Heat dissipation materials 74, 78 are interposed between the first substrate 43 and the sunken portion 32, and between the second substrate 44 and the raised portion 31.

[0049] According to the above configuration, because the heat sink 14 has a stepped shape, each of the two substrates 43, 44 arranged side by side can be brought into contact with the heat sink 14. As a result, heat generated in the first substrate 43 is dissipated to the heat sink 14 via the sunken portion 32, and heat generated in the second substrate 44 is dissipated to the bearing holder via the raised portion 31. This makes it possible to efficiently dissipate heat generated in the first substrate 43 and the second substrate 44 while preventing the motor unit 1 from becoming larger in the axial direction compared to, for example, a case in which a separate heat sink is provided between the first substrate 43 and the second substrate 44.

[0050] (4) The external connector 42 further has a first board support 63 that protrudes from the base portion 61 toward the motor 2. The first board 43 is fixed to the tip of the first board support 63. According to the above configuration, the first board 43 is fixed to the external connector 42, which is the object to be positioned, so that the relative positions of the first board 43 and the external connector 42 can be suitably maintained.

[0051] (5) The external connector 42 further has second board support posts 64 that protrude from the base portion 61 toward the motor 2. The second board 44 is fixed to the tip of the second board support posts 64. According to the above configuration, the second board 44 is fixed to the external connector 42, which is the object of positioning, so that the relative positions of the second board 44 and the external connector 42 can be suitably maintained.

[0052] (6) The heat sink 14 has a positioning hole 36 provided at a position corresponding to the first through hole 71 and the second through hole 72. A common positioning pin 65 is inserted into the first through hole 71, the second through hole 72, and the positioning hole 36. According to the above configuration, the heat sink 14 is positioned with respect to the external connector 42 by the positioning pin 65, which positions the first substrate 43 and the second substrate 44. Therefore, compared to when the heat sink 14 is positioned with respect to the external connector 42 via another member, for example, it is possible to suppress large variations in the relative positions of the first substrate 43, the second substrate 44, and the heat sink 14.

[0053] (7) The motor 2 further includes a rotating shaft 23 and a sensor magnet 26 fixed to a first side end of the rotating shaft 23. The heat sink 14 is configured to hold a bearing 27 that rotatably supports the rotating shaft 23. The circuit component 46 includes a magnetic sensor 91 mounted on the second substrate 44 to face the sensor magnet 26.

[0054] According to the above configuration, the rotating shaft 23 is rotatably supported by the heat sink 14, which prevents the variation in the relative position between the heat sink 14 and the substrates 43, 44 from increasing. This prevents the variation in the relative position between the sensor magnet 26 fixed to the rotating shaft 23 and the magnetic sensor 91 from increasing. This allows the rotation angle of the motor 2 to be detected with high accuracy.

[0055] (8) The circuit components 46 include a drive circuit component 92 that constitutes a drive circuit for supplying drive power to the motor 2. The drive circuit component 92 is mounted in an area of ​​the second substrate 44 facing the raised portion 31. This allows heat generated in the drive circuit component 92 to be efficiently dissipated to the raised portion 31. The amount of heat generated by the drive circuit component 92 tends to be greater than that of other circuit components. In this regard, the raised portion 31 can have a greater thickness along the axis L of the motor 2 than the sunken portion 32. Therefore, by mounting the drive circuit component 92 in an area of ​​the second substrate 44 facing the raised portion 31, overheating of the drive circuit component 92 can be effectively prevented.

[0056] (9) The circuit components 46 include a control circuit component 93 that constitutes a control circuit for controlling the operation of the drive circuit. The control circuit component 93 is mounted on the first substrate 43. This allows heat generated in the control circuit component 93 to be efficiently dissipated to the sinking portion 32. The amount of heat generated by the control circuit component 93 tends to be large compared to other circuit components that constitute the control circuit. Therefore, by mounting the control circuit component 93 on the first substrate 43, it is possible to effectively prevent the control circuit component 93 from overheating.

[0057] (10) The second substrate 44 is rigidly fixed to the heat sink 14. The circuit components 46 include large, heavy components 94 that include a capacitor and a coil. The large, heavy components 94 are mounted on the second substrate 44. According to the above configuration, the second substrate 44 is rigidly fixed to the heat sink 14, which has high rigidity. Therefore, even if the large, heavy components 94 are mounted on the second substrate 44, the second substrate 44 can be prevented from vibrating significantly when subjected to external vibrations.

[0058] (11) The circuit components 46 include lightweight, low heat-generating components 95 that include a pre-driver and a power supply IC. The lightweight, low heat-generating components 95 are mounted mainly in an area of ​​the second substrate 44 facing the sunken portion 32. As a result, heat generated in the lightweight, low heat-generating components 95 is dissipated from the area of ​​the second substrate 44 facing the sunken portion 32 to the area of ​​the second substrate 44 facing the raised portion 31, via the area. In this way, the heat generated in the lightweight, low heat-generating components 95 is difficult to dissipate efficiently, but because the amount of heat generated by the lightweight, low heat-generating components 95 is small, overheating of the lightweight, low heat-generating components 95 can be prevented. As a result, the circuit components 46 can be mounted over the entire second substrate 44 while preventing all of the circuit components 46 from overheating.

[0059] This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility. The lightweight, low heat generating components 95 may be mounted mainly in the area facing the protruding portion 31 on the first substrate 43 or the second substrate 44 .

[0060] The large, heavy component 94 may be mounted in an area of ​​the first substrate 43 or the second substrate 44 facing the recessed portion 32 . The control circuit components 93 may be mounted on the second substrate 44.

[0061] The drive circuit components 92 may be mounted in an area facing the recessed portion 32 on the first substrate 43 or the second substrate 44 . Although the magnetic sensor 91 is mounted on the second board 44, this is not limiting and it may be mounted on the first board 43. In this case, the first board 43 extends to a position facing the rotation shaft 23. Also, the magnetic sensor 91 does not have to be included in the circuit component 46. In other words, the motor unit 1 does not have to include the sensor magnet 26 and the magnetic sensor 91.

[0062] While the inner circumferential surface of the positioning hole 36 and the outer circumferential surface of the tip of the positioning pin 65 are both cylindrical, this is not limiting. For example, as shown in FIG. 4 , the outer circumferential surface of the tip 101 of the positioning pin 65, which protrudes from the first through hole 71 to the second side, may have a locking recess 102, and the inner circumferential surface of the positioning hole 36 may have a locking protrusion 103 that locks into the locking recess 102. The locking recess 102 may be, for example, a groove extending circumferentially of the tip 101 or a hole recessed radially of the tip 101. The locking protrusion 103 may be, for example, a flange-like protrusion extending circumferentially of the positioning hole 36 or a protrusion protruding radially. With this configuration, the external connector 42 is directly fixed to the heat sink 14, thereby enabling the external connector 42 to be securely fixed to the motor 2.

[0063] Although the large diameter portion 68 of the positioning pin 65 does not abut against the surface of the second substrate 44, this is not limited to this. For example, as shown in FIG. 4, the tip of the large diameter portion 68 may abut against the surface of the second substrate 44. In this case, the large diameter portion 68 corresponds to the abutting portion, and the surface of the second substrate 44 corresponds to the opposing surface facing the external connector 42. With this configuration, the second substrate 44 is supported by the large diameter portion 68, thereby more firmly fixing the second substrate 44. Note that the control device 3 in the example shown in FIG. 4 has both the feature that the positioning pin 65 has the locking recess 102 and the positioning hole 36 has the locking protrusion 103, and the feature that the large diameter portion 68 abuts against the surface of the second substrate 44, but may have only one of these features.

[0064] A core material such as a metal rod may be provided inside the positioning pin 65. The first board 43 and the second board 44 are disposed between the motor 2 and the external connector 42 in a position perpendicular to the axis L of the motor 2, but this is not limiting, and the first board 43 and the second board 44 may be disposed in a position intersecting the axis L. Furthermore, the second board 44 does not have to be parallel to the first board 43.

[0065] Although the first board 43 is fixed only to the first board support posts 63, this is not limiting, and the first board 43 may be fixed to the heat sink 14 in addition to the first board support posts 63. Also, the first board 43 may not be fixed to the first board support posts 63, but may be fixed only to the heat sink 14. In this case, the external connector 42 does not need to have the first board support posts 63.

[0066] The second substrate 44 is fixed to the second substrate support posts 64 and the heat sink 14 in the above embodiment, but this is not limiting. The second substrate 44 may be fixed only to the heat sink 14, without being fixed to the second substrate support posts 64. In this case, the external connector 42 may not have the second substrate support posts 64. Furthermore, the second substrate 44 may be fixed only to the second substrate support posts 64, without being fixed to the heat sink 14.

[0067] While the first substrate 43 is fixed to the tip of the first substrate support column 63 with the first screw 73, this is not limiting, and the first substrate 43 may be fixed to the tip of the first substrate support column 63 by, for example, snap fitting. Also, the first substrate 43 may be fixed to the tip of the first substrate support column 63 using, for example, adhesive, and the method of fixing the first substrate 43 to the first substrate support column 63 can be changed as appropriate. Similarly, the method of fixing the second substrate 44 to the second substrate support column 64 and the method of fixing the second substrate 44 to the heat sink 14 can be changed as appropriate.

[0068] The heat sink 14 has the raised portion 31 and the sunken portion 32 and is formed in a stepped plate shape, but this is not limited thereto and may be formed in, for example, a generally flat plate shape. In this case, only the first substrate 43 or the second substrate 44 comes into contact with the heat sink 14. Furthermore, the heat sink 14 does not need to have the support protrusions 34, regardless of whether the heat sink 14 is formed in a stepped plate shape.

[0069] The heat sink 14 does not have to have the positioning holes 36. Furthermore, the heat sink 14 does not have to have the retaining holes 33, regardless of whether the positioning holes 36 are present. In this case, the motor 2 may be provided with a bearing holder that holds the bearings 27, separate from the heat sink 14.

[0070] The motor unit 1 does not have to include the board-to-board connector pair 45. In this case, the first board 43 and the second board 44 may be electrically connected using a connecting member such as a bus bar or a connecting pin.

[0071] The motor unit 1 does not need to include the cover 41. While the motor 2 is a three-phase brushless motor in the above embodiment, it may be a motor of another type, such as a brushed motor. The stator 12 may also have a single coil group 22. In other words, the motor 2 does not necessarily have to have a redundant configuration for the motor coils.

[0072] The control device 3 has a configuration in which the power supply system and the control system for the coil group 22 are made redundant, but it may also be configured so that only the power supply system is made redundant.

Claims

1. A motor; a control device configured to control the motor, The control device an external connector disposed along an axis of the motor and spaced apart from the motor; a first substrate disposed between the motor and the external connector in a position intersecting an axis of the motor; a second substrate disposed between the first substrate and the external connector and parallel to the first substrate; circuit components mounted on the first substrate and the second substrate; The external connector is A base portion; a positioning pin protruding from the base portion toward the motor, the first substrate has a first through hole; the second substrate has a second through hole provided at a position corresponding to the first through hole; the common positioning pin is inserted into the first through hole and the second through hole, the motor includes a heat sink made of a metal material; The heat sink is A ridge; a sunken portion that is sunken so as to be farther away from the external connector than the raised portion, the second substrate is disposed on the raised portion so as to cover a portion of the depressed portion; The first substrate is disposed between the sinking portion and the second substrate.

2. 2. The motor unit according to claim 1, The control device further includes a pair of board-to-board connectors including a first connector mounted on the first board and a second connector mounted on the second board and connected to the first connector, the motor unit.

3. 3. The motor unit according to claim 1 or 2, A motor unit, wherein a heat dissipation material is interposed between the first substrate and the sunken portion and between the second substrate and the raised portion.

4. 2. The motor unit according to claim 1, the external connector further includes a first board support pillar protruding from the base portion toward the motor; The first board is fixed to the tip of the first board support column.

5. 2. The motor unit according to claim 1, the external connector further includes a second board support that protrudes from the base portion toward the motor; The second substrate is fixed to the tip of the second substrate support column.

6. 2. The motor unit according to claim 1, the heat sink has positioning holes provided at positions corresponding to the first through hole and the second through hole; A motor unit, wherein the common positioning pin is inserted into the first through hole, the second through hole, and the positioning hole.

7. 7. The motor unit according to claim 6, The motor A rotation axis; a sensor magnet fixed to an end of the rotating shaft, the circuit component includes a magnetic sensor mounted on the first substrate or the second substrate so as to face the sensor magnet, The heat sink is configured to hold a bearing that rotatably supports the rotating shaft.

8. 8. The motor unit according to claim 6 or 7, The positioning pin has a tip portion that is inserted into the positioning hole, The outer peripheral surface of the tip portion has a locking recess, The inner circumferential surface of the positioning hole has a locking protrusion that locks into the locking recess.

9. 2. The motor unit according to claim 1, the circuit components include drive circuit components that configure a drive circuit for supplying drive power to the motor; The drive circuit components are mounted in an area of ​​the second substrate facing the raised portion.

10. 2. The motor unit according to claim 1, the circuit components include control circuit components that configure a control circuit for controlling the operation of the motor; The control circuit components are mounted on the first substrate.

11. 2. The motor unit according to claim 1, the second substrate is rigidly fixed to the heat sink; the circuit components include large, heavy components including capacitors and coils; The large, heavy component is mounted on the second board.

12. 2. The motor unit according to claim 1, The positioning pin has an abutment portion configured to abut against a surface of the second substrate facing the external connector.

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