Motor unit, blower and moving body

Abstract

This motor unit for rotating and driving a centrifugal fan is equipped with a rotor, a stator which faces the rotor, a circuit board configured so as to control the conduction of electricity to the stator, and a motor case which houses the rotor, the stator and the circuit board. The motor case includes a member for forming a ventilation channel between said case and the centrifugal fan. At least part of the member for forming the ventilation channel is a heat-transmitting part which contacts the circuit board in a manner such that heat conduction is possible.

Description

Motor unit, blower, and moving body

[0001] The present disclosure relates to a motor unit, a blower, and a moving body.

[0002] 2. Description of the Related Art A conventional blower including a centrifugal fan is known, and is installed in a vehicle such as an automobile. This type of blower includes a fan unit and a motor unit attached to the fan unit (see Patent Document 1).

[0003] The fan unit includes a centrifugal fan and a fan case. The fan unit houses the centrifugal fan in the fan case. The motor unit includes a rotor, a stator, and a motor case. The motor unit houses the rotor and the stator in the motor case.

[0004] In recent years, there has been a demand for higher output of the above-mentioned blowers, and as the output of the blowers increases, heat generation from the motor unit becomes a problem.

[0005] International Publication No. 2016 / 059776

[0006] The present disclosure aims to improve the heat dissipation performance of a motor unit.

[0007] A motor unit according to one aspect of the present disclosure is a motor unit for rotating a centrifugal fan, and includes a rotor, a stator facing the rotor, a circuit board configured to control the supply of current to the stator, and a motor case that houses the rotor, the stator, and the circuit board. The motor case includes a member that forms an air passage between the motor case and the centrifugal fan. At least a portion of the member that forms the air passage is a heat conductive part that is in thermally conductive contact with the circuit board.

[0008] The heat conducting portion is preferably a metal portion.

[0009] It is preferable that the motor unit further includes an insulating member disposed between the circuit board and the metal portion, and the metal portion is in thermally conductive contact with the circuit board via the insulating member.

[0010] The motor case may have a hole formed therein to expose a portion of the circuit board.

[0011] The member forming the ventilation passage is preferably made up of the metal part and a resin part provided integrally with the metal part.

[0012] It is preferable that the metal portion constitutes a radially inner portion of the member that forms the ventilation passage.

[0013] It is preferable that the motor unit further includes a bearing that rotatably supports the rotor, and a part of the metal portion forms a metal holder that holds the bearing.

[0014] A blower according to another aspect of the present disclosure includes the motor unit, the centrifugal fan that is rotationally driven by the rotor, and a fan case that rotatably houses the centrifugal fan.

[0015] It is preferable that the blower further includes a sub-ventilation passage connected to the ventilation passage, and the sub-ventilation passage is formed between the motor case and the fan case.

[0016] The motor case may have a hole formed therein that exposes a portion of the circuit board, and the secondary ventilation passage may be formed between the fan case and a portion of the motor case where the hole is not formed.

[0017] The motor case may have a hole formed therein that exposes a portion of the circuit board, and the hole may be covered by the fan case.

[0018] A moving body according to another aspect of the present disclosure includes the blower, an object to be cooled by the blower, and a vehicle body on which the blower and the object to be cooled are mounted.

[0019] The present disclosure provides an effect of improving the heat dissipation performance of the motor unit.

[0020] FIG. 1 is a front view of a blower according to an embodiment. FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1. FIG. 3 is an enlarged view of a main portion of FIG. 2. FIG. 4 is an exploded perspective view of the blower. FIG. 5 is a rear view of a fan case provided in the blower. FIG. 6 is a perspective view of a first member and a circuit board provided in the blower. FIG. 7 is a perspective view of a metal part included in the first member provided in the blower. FIG. 8 is a conceptual diagram of a moving object equipped with the blower.

[0021] The embodiments and modifications described below are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments and modifications. Various modifications other than these embodiments and modifications are possible depending on the design, etc., as long as they do not deviate from the technical concept of the present disclosure. The configurations of the modifications can also be applied in appropriate combinations.

[0022] (1) Embodiment A blower 1 according to an embodiment will be described in detail with reference to the accompanying drawings. The blower 1 is suitably mounted on a mobile object 9 such as an automobile. The blower 1 may also be mounted on other devices such as home appliances.

[0023] (1-1) Overall Structure of the Blower Fig. 1 is a front view of a blower 1 according to an embodiment. Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1. As shown in Figs. 1 and 2, the blower 1 includes a fan unit 12 and a motor unit 14.

[0024] The fan unit 12 and the motor unit 14 are assembled together. When viewed in the axial direction of the fan unit 12, the motor unit 14 has a smaller outer shape than the fan unit 12. In other words, the axial direction of the fan unit 12 is the direction along the axis of the centrifugal fan 2 included in the fan unit 12.

[0025] When the fan unit 12 and the motor unit 14 are assembled together, the axis of the centrifugal fan 2 coincides with the axis of the rotating shaft 514 of the motor unit 14. Hereinafter, the state in which the fan unit 12 and the motor unit 14 are assembled together will be referred to as the assembled state.

[0026] The fan unit 12 is a centrifugal fan unit. The fan unit 12 is configured to take in air along the axis of the centrifugal fan 2 and exhaust air in a direction intersecting the axis of the centrifugal fan 2 (in this embodiment, a direction perpendicular to the axis of the centrifugal fan 2). The orientation of the motor unit 14 relative to the fan unit 12 coincides with the direction in which the fan unit 12 takes in air.

[0027] 2, in the assembled state, a portion of the motor unit 14 is inserted inside the fan unit 12. In this case, the portion of the motor unit 14 includes a portion of the motor case 6 (more specifically, a portion of a member 61 described below) that forms the outer shell of the motor unit 14.

[0028] The specific configurations of the fan unit 12 and the motor unit 14 will be further described below.

[0029] (1-2) Fan Unit The fan unit 12 includes a centrifugal fan 2 and a fan case 3 that rotatably houses the centrifugal fan 2. In the blower 1, the centrifugal fan 2 and the fan case 3 are made of resin. However, all or part of the centrifugal fan 2 may be made of metal, and all or part of the fan case 3 may be made of metal.

[0030] The centrifugal fan 2 includes a hub 21 and a plurality of blades 23. In the blower 1, the centrifugal fan 2 is a sirocco fan. Hereinafter, the orientation of a first side along the axis of the centrifugal fan 2 will be referred to as a first orientation D1. The orientation of a second side, opposite to the orientation of the first side along the axis of the centrifugal fan 2, will be referred to as a second orientation D2.

[0031] In the assembled state, the fan unit 12 is positioned in a first direction D1 with respect to the motor unit 14. The motor unit 14 is positioned in a second direction D2 with respect to the fan unit 12.

[0032] The hub 21 of the centrifugal fan 2 has a shape recessed in the first direction D1. In the assembled state, a part of the motor case 6 (more specifically, a part of a member 61 described below) is disposed inside the recess of the hub 21.

[0033] The center of the hub 21 is located closest to the first direction D1 of the entire hub 21. The hub 21 includes a connecting portion 215 that forms the center of the hub 21. The connecting portion 215 is a portion into which one axial end of the rotating shaft 514 is fitted. The one axial end of the rotating shaft 514 is connected to the connecting portion 215 so as to be rotatable together with the rotating shaft 514.

[0034] The hub 21 further includes a bottom wall portion 216 that is positioned to completely surround the connecting portion 215. The bottom wall portion 216 extends radially outward from the outer periphery of the connecting portion 215. The radially inner portion of the bottom wall portion 216 is inclined as a whole so that the portion closer to the connecting portion 215 is positioned closer to the first direction D1.

[0035] Each of the plurality of blades 23 is provided integrally with a radially outer portion of the bottom wall portion 216 of the hub 21. Each of the plurality of blades 23 extends in a first direction D1 from the radially outer portion of the bottom wall portion 216 of the hub 21. The plurality of blades 23 are arranged at intervals in the circumferential direction.

[0036] The fan case 3 includes an intake port 34 for drawing in outside air, an outlet port 35 for discharging air toward the outside space, and a flow path 36 connecting the intake port 34 and the outlet port 35. When the centrifugal fan 2 rotates inside the fan case 3, air drawn in through the intake port 34 in the second direction D2 is guided along the flow path 36 to the outlet port 35.

[0037] The fan case 3 includes a first member 31 that forms one half of the fan case 3 and a second member 32 that forms the other half of the fan case 3. The first member 31 and the second member 32 are fitted together to form the fan case 3. The first member 31 forms the half of the fan case 3 that faces the first direction D1. The second member 32 forms the half of the fan case 3 that faces the second direction D2.

[0038] The intake port 34 is included in the first member 31. The intake port 34 is open in a first direction D1. The discharge port 35 is open in a direction perpendicular to the first direction D1. The discharge port 35 is formed when the first member 31 and the second member 32 are fitted together. The flow path 36 forms a spiral that surrounds the periphery of the centrifugal fan 2. The flow path 36 is formed when the first member 31 and the second member 32 are fitted together.

[0039] The fan case 3 further includes a connection portion 33. The connection portion 33 is a portion to which the motor unit 14 is connected. The connection portion 33 is included in the second member 32. When the first member 31 and the second member 32 are fitted together, the connection portion 33 included in the second member 32 faces the intake port 34 included in the first member 31.

[0040] Fig. 4 is an exploded perspective view of the blower 1 according to the embodiment. Fig. 5 is a rear view of the fan case 3 included in the blower 1. The connection portion 33 includes a wall portion 38 located opposite the intake port 34 and a connection opening 30 surrounded by the wall portion 38 (see Figs. 4 and 5).

[0041] The opening 30 is a circular opening facing the intake port 34. The axis of the centrifugal fan 2 is set to pass through the center of the opening 30. The opening 30 is an opening for inserting a part of the motor case 6 (more specifically, a part of a member 61 described below) that forms the outer shell of the motor unit 14 into the inside of the fan case 3.

[0042] The wall portion 38 is positioned around the opening 30. The opening 30 is configured as a hole that penetrates the center of the wall portion 38. The wall portion 38 includes an annular surface 380 that surrounds the opening 30. The surface 380 of the wall portion 38 faces in the second direction D2.

[0043] The surface 380 is formed with a plurality of recesses 37 for forming sub-ventilation passages 45 (described later) and a protrusion 39 for mounting the motor unit 14 .

[0044] In the blower 1, the multiple recesses 37 are formed at intervals from one another in the circumferential direction surrounding the opening 30. More specifically, the multiple recesses 37 are two recesses 37 positioned at an interval from one another in the circumferential direction. Each recess 37 has a shape that extends radially outward in the radial direction from the periphery of the opening 30. In other words, each recess 37 is formed so that the width increases the farther it is from the opening 30.

[0045] In the blower 1, the multiple protrusions 39 are formed at intervals from one another in the circumferential direction surrounding the opening 30. More specifically, the multiple protrusions 39 are three protrusions 39 positioned at intervals from one another in the circumferential direction. Each of the protrusions 39 has a pin-like shape that protrudes in the second direction D2.

[0046] In the circumferential direction surrounding the opening 30, the region where the plurality of recesses 37 are formed and the region where the plurality of protrusions 39 are formed are different from each other. In the circumferential direction surrounding the opening 30, at least one protrusion 39 is located in the regions on both sides of each recess 37.

[0047] (1-3) Motor Unit The motor unit 14 is composed of an inner rotor type brushless motor. The motor unit 14 is integrally assembled to the fan unit 12 to drive and rotate the centrifugal fan 2 provided in the fan unit 12. The centrifugal fan 2 is driven to rotate around the axis of the centrifugal fan 2 in accordance with the rotation of the rotor 51 provided in the motor unit 14.

[0048] The motor unit 14 includes an electric mechanism 5 for rotating the centrifugal fan 2 and a motor case 6 that houses the electric mechanism 5 .

[0049] The electric mechanism 5 includes a rotor 51, a bearing 521, another bearing 522, a stator 54, a circuit board 57, and an insulating member 56. Hereinafter, the bearing 521 will be referred to as a first bearing 521, and the bearing 522 will be referred to as a second bearing 522.

[0050] (1-4) Rotor The rotor 51 includes an annular rotor core 511 in which magnets are arranged, and a rotating shaft 514 connected to the rotor core 511. The rotor core 511 and the rotating shaft 514 can rotate together around the axis of the rotating shaft 514.

[0051] The end of the rotary shaft 514 on the first direction D1 side protrudes outside the motor case 6. The end of the rotary shaft 514 on the first direction D1 side is fitted into the connecting portion 215 of the centrifugal fan 2 so as to be rotatable together with the rotor 51 (i.e., the rotor core 511 and the rotary shaft 514).

[0052] (1-5) First Bearing The first bearing 521 rotatably supports an axially intermediate portion of the rotary shaft 514, and therefore rotatably supports the rotor 51. In the motor unit 14, the first bearing 521 is a ball bearing.

[0053] The first bearing 521 is fitted into a part of the motor case 6 (more specifically, a part of a member 61 described below).

[0054] The portion of the rotating shaft 514 that is rotatably supported by the first bearing 521 is located closer to the first direction D1 than the portion of the rotating shaft 514 that is connected to the rotor core 511 .

[0055] (1-6) Second Bearing The second bearing 522 rotatably supports the end of the rotating shaft 514 on the second direction D2 side, and therefore rotatably supports the rotor 51. In the motor unit 14, the second bearing 522 is a ball bearing. The rotor 51 is rotatably supported by the first bearing 521 and the second bearing 522.

[0056] The second bearing 522 is fitted into a part of the motor case 6 (more specifically, a part of a member 62 described below). The second bearing 522 is positioned in a second direction D2 with the first bearing 521 as the reference.

[0057] The portion of the rotating shaft 514 that is rotatably supported by the second bearing 522 is located closer to the second direction D2 than the portion of the rotating shaft 514 that is connected to the rotor core 511.

[0058] (1-7) Stator The stator 54 faces the rotor 51. The stator 54 is configured to supply a magnetic force that rotates the rotor 51. The stator 54 includes a stator core 541 and a winding 543 wound around the stator core 541. The stator 54 is disposed radially outward of the rotor 51.

[0059] The stator 54 is in thermally conductive contact with the motor case 6. Specifically, the outer peripheral surface of the stator core 541 is in thermally conductive contact with the inner peripheral surface of the motor case 6 (specifically, the inner peripheral surface of the member 62). The motor case 6 and the stator core 541 may be thermally coupled by direct contact, or may be thermally coupled via a thermally conductive member sandwiched therebetween.

[0060] (1-8) Circuit Board The circuit board 57 is configured to control the supply of current to the stator 54. The circuit board 57 is arranged closer to the first direction D1 than the rotor core 511. The circuit board 57 is arranged closer to the first direction D1 than the stator 54.

[0061] In the assembled state, the circuit board 57 is located between the centrifugal fan 2 and the rotor core 511. The circuit board 57 is located between the centrifugal fan 2 and the stator .

[0062] 4, the circuit board 57 has an annular shape. The outer diameter of the annular circuit board 57 is smaller than the outer diameter of the annular stator 54 and larger than the outer diameter of the rotor 51. The inner diameter of the circuit board 57 is smaller than the inner diameter of the stator 54 and smaller than the outer diameter of the rotor 51.

[0063] Fig. 3 is an enlarged view of a main portion of Fig. 2. As shown in Fig. 3, the circuit board 57 is capable of conducting heat to the motor case 6 (specifically, member 61) via the sheet-like insulating member 56. The heat conducted from the circuit board 57 to the motor case 6 via the insulating member 56 is dissipated through the outer surface of the motor case 6 (mainly the outer surface of member 61).

[0064] (1-9) Insulating Member The insulating member 56 has electrical insulation properties. The insulating member 56 is a sheet-like member that has thermal conductivity. The insulating member 56 has an annular shape.

[0065] The insulating member 56 is disposed between the circuit board 57 and the motor case 6. The insulating member 56 is disposed between the circuit board 57 and the member 61. More specifically, the insulating member 56 is disposed between the circuit board 57 and the metal part 7 that constitutes the heat conduction part 63 described below.

[0066] The outer diameter of the annular insulating member 56 is smaller than the outer diameter of the annular stator 54 and larger than the outer diameter of the rotor 51. The outer diameter of the insulating member 56 is smaller than the outer diameter of the circuit board 57. The inner diameter of the insulating member 56 is smaller than the inner diameter of the stator 54 and larger than the inner diameter of the circuit board 57.

[0067] When viewed in the axial direction of the rotating shaft 514, the insulating member 56 is positioned so as to overlap the circuit board 57. When viewed in the axial direction of the rotating shaft 514, the insulating member 56 is positioned so as to overlap the member 61.

[0068] (1-10) Motor Case The motor case 6 is a case that houses the rotor 51, the first bearing 521, the second bearing 522, the stator 54, the circuit board 57, and the insulating member 56.

[0069] The motor case 6 is constructed by fitting together an annular member 61, which forms the ventilation passage 4 between the centrifugal fan 2 and the member 61, and another cup-shaped member 62. Hereinafter, the member 61 will be referred to as the first member 61. The member 62 will be referred to as the second member 62. The first member 61 is a member that constitutes the half of the motor case 6 that is closer to the fan unit 12. The second member 62 is a member that constitutes the half of the motor case 6 that is farther from the fan unit 12.

[0070] An opening that is open in the first direction D1 is formed in the second member 62. The opening of the cup-shaped second member 62 is covered by the lid-shaped first member 61. In this way, the motor case 6 is formed.

[0071] The second member 62 has a flange-shaped outer peripheral edge 622. A plurality of positioning through holes 625 are formed in the outer peripheral edge 622 (see FIG. 4 ). In the motor unit 14, the plurality of through holes 625 are formed at intervals from one another in the circumferential direction. More specifically, the plurality of through holes 625 are three through holes 625 positioned at intervals from one another in the circumferential direction. Each through hole 625 receives a corresponding one of the three protrusions 39 of the fan case 3.

[0072] The first bearing 521, the insulating member 56, and the circuit board 57 are assembled to the first member 61. The second bearing 522, the rotor 51, and the stator 54 are assembled to the second member 62.

[0073] The first member 61 is composed of a heat conductive portion 63 and a resin portion 8 provided integrally with the heat conductive portion 63. The heat conductive portion 63 is a metal portion 7 having thermal conductivity.

[0074] A zinc-plated steel plate can be used as the metal constituting the metal portion 7. A polybutylene terephthalate (PBT) or polypropylene (PP) can be used as the resin constituting the resin portion 8.

[0075] (1-11) Metal Part The metal part 7 that constitutes the heat conduction part 63 is a metal member that constitutes part of the first member 61. The metal part 7 constitutes the radially inner part of the first member 61. In the motor unit 14, the radially inner half of the first member 61 is constituted by the annular metal part 7.

[0076] 7 is a perspective view of the metal part 7 included in the first member 61 of the blower 1 according to the embodiment. As shown in FIGS. 3 and 7 , the annular metal part 7 includes an annular first part 71 provided in a radially intermediate portion, a second part 72 provided radially inward from the first part 71, and a third part 73 provided radially outward from the first part 71. The second part 72 is the radially innermost part of the metal part 7. The third part 73 is the radially outermost part of the metal part 7.

[0077] The first portion 71 of the metal portion 7 is formed in a flat annular plate shape so as to connect the second portion 72 and the third portion 73. The first portion 71 has a shape that is recessed in the second direction D2 compared to the surrounding portions of the metal portion 7. The first portion 71 of the metal portion 7 protrudes in the second direction D2 more than the second portion 72 and the third portion 73, and thus has a shape that is recessed downward in FIG.

[0078] The first portion 71 is a portion that is in thermally conductive contact with the circuit board 57. In other words, the first portion 71 is a main portion of the metal portion 7. For example, as shown in FIG. 3 , an insulating member 56 is attached to the surface of the first portion 71 facing the second direction D2. In the motor unit 14, the first portion 71 of the metal portion 7 and the circuit board 57 are in thermally conductive contact via the insulating member 56. Here, the thermally conductive contact between the metal portion 7 and the circuit board 57 includes the case where the insulating member 56 is interposed between the metal portion 7 and the circuit board 57. It is sufficient that the metal portion 7 and the circuit board 57 are thermally coupled via the insulating member 56.

[0079] The second portion 72 of the metal portion 7 has a shape that protrudes in a first direction D1 from the radially inner end of the first portion 71. The second portion 72 protrudes in the first direction D1 further than the first portion 71, and thus has a shape that is convex upward in FIG. 3 . The second portion 72 constitutes a metal holder 75 that holds the first bearing 521 therein. The first bearing 521 is fitted into the inner circumferential surface of the holder 75, and thereby the first bearing 521 is held in the metal portion 7.

[0080] The third portion 73 of the metal portion 7 has a shape that slightly protrudes in the first direction D1 from the radially outer end of the first portion 71. The third portion 73 has a shape that is convex upward in Fig. 3 because it protrudes slightly in the first direction D1 beyond the first portion 71. The dimension by which the third portion 73 protrudes from the first portion 71 in the first direction D1 is smaller than the dimension by which the second portion 72 protrudes from the first portion 71 in the first direction D1.

[0081] The third portion 73 is a portion that is mechanically coupled to the resin portion 8. As shown in Fig. 7, the third portion 73 has through holes 735 formed therein to allow resin to enter during insert molding. The motor unit 14 has a plurality of through holes 735 formed therein at intervals in the circumferential direction. Specifically, the plurality of through holes 735 are four through holes 735 that are positioned at equal intervals in the circumferential direction.

[0082] (1-12) Resin Part The resin part 8 is a resin part that constitutes part of the first member 61. The resin part 8 constitutes the radially outer part of the first member 61. In the motor unit 14, the radially outer half of the first member 61 is constituted by the resin part 8.

[0083] 6 is a perspective view of the first member 61 and the circuit board 57 included in the blower 1 of the embodiment. For example, as shown in Figures 3 and 6, the annular resin part 8 includes an annular inner peripheral part 81 that forms the radially inner part of the resin part 8, an annular outer peripheral part 82 that forms the radially outer part of the resin part 8, and a cylindrical connecting part 83 that connects the inner peripheral part 81 and the outer peripheral part 82.

[0084] The inner circumferential portion 81 of the resin part 8 is positioned in the first direction D1 relative to the outer circumferential portion 82. The connecting portion 83 extends in the second direction D2 from a radially outer end of the inner circumferential portion 81. In other words, the connecting portion 83 extends in the first direction D1 from a radially inner end of the outer circumferential portion 82. The outer circumferential portion 82 extends radially outward in a flange-like shape from the end of the connecting portion 83 on the second direction D2 side.

[0085] The inner circumferential portion 81 of the resin part 8 is a portion that is mechanically coupled to the metal part 7. More specifically, a radially inner portion of the inner circumferential portion 81 is mechanically coupled to the third portion 73 of the metal part 7 by insert molding. For example, as shown in FIG. 3 , an insulating member 56 is attached to the surface of the inner circumferential portion 81 facing the second direction D2. In the motor unit 14, the inner circumferential portion 81 of the resin part 8 and the circuit board 57 are in thermally conductive contact via the insulating member 56. In other words, the resin part 8 and the circuit board 57 are thermally coupled via the insulating member 56.

[0086] The outer peripheral portion 82 of the resin part 8 is overlapped with the outer peripheral edge portion 622 of the second member 62, which is made of metal. A plurality of positioning through holes 65 are formed in the outer peripheral portion 82 of the resin part 8 (see FIG. 6 ). In the motor unit 14, the plurality of through holes 65 are formed at intervals in the circumferential direction. More specifically, the plurality of through holes 65 are three through holes 65 positioned at intervals in the circumferential direction. One of the three protrusions 39 of the fan case 3 is inserted into each through hole 65 (see FIG. 4 ).

[0087] Furthermore, a plurality of holes 60 are formed in the resin portion 8 to expose portions of the circuit board 57. The portions of the circuit board 57 exposed through the holes 60 include portions where lead wires are soldered. In the motor unit 14, the plurality of holes 60 are formed at intervals from one another in the circumferential direction. The plurality of holes 60 are six holes 60 positioned at intervals from one another in the circumferential direction.

[0088] 6 , each hole 60 is formed from the inner circumferential portion 81 to the connecting portion 83 of the resin portion 8. Each hole 60 includes a first hole portion 601 formed in a radially outer portion of the inner circumferential portion 81 and a second hole portion 602 formed in the connecting portion 83. The first hole portion 601 opens in a first direction D1. The second hole portion 602 opens radially outward.

[0089] As shown in FIG. 3 , in the assembled state, the circuit board 57 is located radially inside the connecting portion 83 of the resin part 8 .

[0090] The portions of the circuit board 57 exposed from each hole 60 are included in the radially outermost portion 572 of the circuit board 57 (see FIG. 6 ). Of the portion 572 of the circuit board 57 that is not exposed from each hole 60, the portion is recessed radially inward relative to the portion exposed from each hole 60. When the circuit board 57 is assembled to the first member 61, portions of the circuit board 57 are exposed from each hole 60 of the first member 61. This makes it possible to solder lead wires to the circuit board 57 through each hole 60.

[0091] A connector housing 88 is molded on the outer peripheral portion 82 of the resin part 8 so as to protrude in the second direction D2. A connection terminal is housed in the connector housing 88. For example, an external power supply is connected to the connection terminal. Power supplied from the external power supply is supplied to the stator 54 through the connection terminal and the circuit board 57.

[0092] 3, the ventilation passage 4 is formed between the motor case 6 and the centrifugal fan 2. More specifically, the ventilation passage 4 is formed between the hub 21 of the centrifugal fan 2 and a portion of the first member 61 of the motor case 6 that is inserted into the inside of the fan case 3 through the opening 30 of the fan case 3.

[0093] The ventilation passage 4 faces the metal portion 7 that constitutes a part of the first member 61. The ventilation passage 4 faces an inner peripheral portion 81 of the resin portion 8 that constitutes another part of the first member 61. In the blower 1, as the centrifugal fan 2 rotates, a radially outward air flow is generated in the ventilation passage 4, as indicated by the dashed arrows in FIG. 3 . Heat generated in the circuit board 57 during operation is transferred to the metal portion 7 and the resin portion 8 via the insulating member 56. The heat generated in the circuit board 57 is effectively dissipated to the air flowing through the ventilation passage 4 through the metal portion 7 and the resin portion 8. The heat generated in the circuit board 57 is dissipated mainly through the metal portion 7.

[0094] Additionally, blower 1 is formed with a secondary ventilation passage 45 that connects to ventilation passage 4. Secondary ventilation passage 45 is formed between motor case 6 and fan case 3. In detail, secondary ventilation passage 45 is formed between a portion of first member 61 of motor case 6 that is not inserted into fan case 3 through opening 30 of fan case 3, and wall portion 38 that surrounds opening 30 of fan case 3.

[0095] The secondary ventilation passages 45 are not formed around the entire circumference, but are formed only in a plurality of regions spaced apart from each other in the circumferential direction. In the blower 1, a secondary ventilation passage 45 is formed between each of two recesses 37 (see FIG. 4 ) provided in the wall portion 38 and the resin portion 8 of the first member 31 of the fan case 3. Each of the two secondary ventilation passages 45 is a ventilation passage that communicates with the opening 30 and also communicates with the external space. The secondary ventilation passages 45 are formed to extend radially outward from the periphery of the opening 30. In other words, the secondary ventilation passages 45 are formed so that the width increases the farther they are from the opening 30.

[0096] In blower 1, no holes 60 are provided in the resin part 8 in the portions facing the recesses 37 of fan case 3. Therefore, secondary ventilation passage 45 is formed between the fan case 3 and the portions of motor case 6 where no holes 60 are formed. In the assembled state, each hole 60 in resin part 8 is covered by the fan case 3.

[0097] In blower 1, no through holes 65 are provided in the resin part 8 in the portions facing the recesses 37 of fan case 3. Therefore, secondary ventilation passage 45 is formed between the fan case 3 and the portions of motor case 6 where no through holes 65 are formed.

[0098] In blower 1, when centrifugal fan 2 rotates, negative pressure is created inside fan case 3, causing an air flow from the external space toward the inside of fan case 3 through sub-ventilation passage 45, as shown by the dashed arrow in Fig. 3. The air flow generated in sub-ventilation passage 45 connected to ventilation passage 4 makes it easier to ensure air flow in ventilation passage 4, and ultimately makes it easier for heat to dissipate into the air flowing through ventilation passage 4.

[0099] The air flow generated in the sub-ventilation passage 45 may be reversed depending on the structure of the blower 1 or various driving conditions. However, even in this case, the air flow in the sub-ventilation passage 45 makes it easier for air to flow into the ventilation passage 4. Consequently, heat is more easily dissipated into the air flowing through the ventilation passage 4.

[0100] (1-14) Assembly Procedure The method for assembling the blower 1 having the motor unit 14 with the above-described configuration includes a first step, a second step, a third step, a fourth step, and a fifth step.

[0101] In a first step, the stator 54 including the stator core 541 and the windings 543 is fitted inside the cup-shaped second member 62 made of metal (see, for example, FIG. 4).

[0102] In the second step, the rotor unit 53 shown in Fig. 4 is fitted inside the second member 62. The rotor unit 53 is a unit in which the rotor 51 including the rotor core 511 and the rotary shaft 514 is integrally assembled with the first bearing 521 and the second bearing 522. The second bearing 522 of the rotor unit 53 is held by the second member 62 by being fitted into a metal holder 628 (see Fig. 3) formed in the center of the second member 62.

[0103] In the third step, the circuit board 57 is fitted inside the first member 61 via the insulating member 56. The circuit board 57 may be fixed to the first member 61 by thermal welding or by screwing. It is also possible to mold the circuit board 57 integrally with the first member 61. In this case, the third step is omitted.

[0104] In the fourth step, the second member 62 into which the stator 54 and the rotor unit 53 are fitted, the first member 61 into which the circuit board 57 and the insulating member 56 are fitted, and the second member 32 of the fan case 3 are assembled together. At this time, the three protrusions 39 protruding from the second member 32 are inserted one-to-one into the three through holes 65 formed in the first member 61. Furthermore, the three protrusions 39 protruding from the second member 32 are inserted one-to-one into the three through holes 625 formed in the second member 62. The first bearing 521 of the rotor unit 53 is held by the first member 61 by being fitted into a metal holder 75 (see FIG. 3 ) formed in the center of the first member 61.

[0105] In the fifth step, the first member 31 is attached to the second member 32, to which the motor unit 14 has been attached through the first to fourth steps, with the centrifugal fan 2 sandwiched between them. This completes the blower 1 having the above-described configuration. Note that the first to fifth steps do not necessarily have to be performed in this order.

[0106] In the motor unit 14, the circuit board 57 is first assembled to the first member 61 as described above, forming a sub-assembly including the first member 61 and the circuit board 57. This makes it possible to prevent variations in the relative positions of the first member 61 and the circuit board 57. This makes it possible to more reliably achieve thermal coupling between the metal part 7 and the circuit board 57. The electrical connection between the circuit board 57 and the stator 54 can be easily achieved by soldering lead wires to the circuit board 57 through each hole 60 in the first member 61.

[0107] (1-15) Mobile Body Fig. 8 is a conceptual diagram of a mobile body 9 equipped with a blower 1 according to an embodiment. The mobile body 9 includes the blower 1, an object 91 to be cooled by the blower 1, and a vehicle body 97 on which the blower 1 and the object 91 to be cooled are mounted. The object 91 to be cooled is, for example, a battery 92.

[0108] The mobile object 9 is a hybrid four-wheeled vehicle equipped with a plurality of wheels 93, and an engine 94 and a motor 95 for driving the wheels 93. The battery 92 is configured to supply power to the motor 95. The mobile object 9 may be another type of four-wheeled vehicle, such as an electric vehicle.

[0109] The moving object 9 on which the blower 1 is mounted is not limited to a four-wheeled vehicle, but may be, for example, a vehicle (automobile) such as a two-wheeled vehicle or a three-wheeled vehicle. The object to be cooled 91 may be a part other than the battery 92.

[0110] (2) Modifications The following are modifications of the blower 1. In each modification of the blower 1, the same reference numerals are used to designate components common to the above-described blower 1, and detailed description thereof will be omitted.

[0111] The motor unit 14 is an inner rotor type. However, the configuration of the motor unit 14 is not limited to this. For example, the motor unit 14 may be an outer rotor type. Even in this case, the heat dissipation properties of the motor unit 14 can be improved by, for example, configuring the first member 61 entirely as a metal part 7, or configuring a radially outer portion of the first member 61 as a metal part 7, making the circuit board 57 in contact with the metal part 7 so as to be capable of thermal conduction, and configuring the metal part 7 to face the ventilation passage 4.

[0112] In the motor unit 14, the circuit board 57 and the metal part 7 are thermally coupled via the sheet-like insulating member 56. However, the form of thermal coupling between the circuit board 57 and the metal part 7 is not limited to this. For example, the circuit board 57 and the metal part 7 may be thermally coupled by direct contact.

[0113] In the motor unit 14, the motor case 6 is composed of a first member 61 and a second member 62. However, the configuration of the motor case 6 is not limited to this. For example, the motor case 6 may be composed of one or more members other than the first member 61 and the second member 62.

[0114] In the motor unit 14, the holes 60 are formed in the resin part 8 of the motor case 6. However, the shape of the holes 60 is not limited to this. For example, the first member 61 may be entirely made of the metal part 7, and the holes 60 may be formed in the metal part 7.

[0115] In the motor unit 14, a holder 75 for holding the first bearing 521 is configured as part of the metal portion 7 of the first member 61. A holder 628 for holding the second bearing 522 is configured as part of the second member 62 made of metal. However, the configuration of the holders 75, 628 is not limited to this. For example, the holder 75 may be configured as a separate body from the metal portion 7. The holder 628 may be configured as a separate body from the second member 62.

[0116] In the motor unit 14, the first member 61 including the metal part 7 and the resin part 8 is integrally molded. However, the molding method of the first member 61 is not limited to this. The first member 61 may be molded by other methods such as thermal welding or screw fixing, in which the metal part 7 and the resin part 8 are fixed.

[0117] In the motor unit 14, the resin part 8 includes the connector housing 88, and the connector housing 88 is molded together with the first member 61 when the first member 61 is molded by integral molding. However, the connector housing 88 can also be formed as a separate member from the first member 61.

[0118] (3) Summary As described above, the motor unit (14) according to the first aspect is a motor unit (14) for rotationally driving a centrifugal fan (2), and includes a rotor (51), a stator (54) facing the rotor (51), a circuit board (57) configured to control the supply of electricity to the stator (54), and a motor case (6) that houses the rotor (51), the stator (54), and the circuit board (57). The motor case (6) includes a member (61) that forms an air passage (4) between the motor case (6) and the centrifugal fan (2). At least a portion of the member (61) that forms the air passage (4) is a heat-conducting portion (63) that is in thermally conductive contact with the circuit board (57).

[0119] According to this aspect, heat generated in the circuit board (57) is conducted to the heat conductive portion (63) and is effectively dissipated through the heat conductive portion (63) to the air flowing through the ventilation passage (4). This improves the heat dissipation performance of the motor unit (14). This in turn increases the input power to the motor unit (14) and increases output. This reduces the need to use highly heat-resistant circuit components. This increases design freedom and facilitates cost reduction.

[0120] In the motor unit (14) according to the second aspect, in the first aspect, the heat conducting portion (63) is a metal portion (7).

[0121] According to this embodiment, heat generated in the circuit board (57) is conducted to the metal portion (7) and is effectively dissipated through the metal portion (7) to the air flowing through the ventilation passage (4).

[0122] The motor unit (14) according to a third aspect is the motor unit (14) of the second aspect, further comprising an insulating member (56) disposed between the circuit board (57) and the metal portion (7). The metal portion (7) is in thermally conductive contact with the circuit board (57) via the insulating member (56).

[0123] According to this aspect, insulation between the circuit board (57) and the metal part (7) can be ensured via the insulating member (56).

[0124] In the motor unit (14) according to the fourth aspect, in any one of the first to third aspects, a hole (60) is formed in the motor case (6) to expose a portion of the circuit board (57).

[0125] According to this embodiment, while the circuit board (57) is kept in thermally conductive contact with the metal part (7) that constitutes part of the motor case (6), lead wires can be soldered to the circuit board (57) through the hole (60) in the motor case (6).

[0126] In the motor unit (14) according to the fifth aspect, in the second or third aspect, the member (61) forming the ventilation passage (4) is composed of a metal part (7) and a resin part (8) formed integrally with the metal part (7).

[0127] According to this aspect, the overall weight of the motor case (6) can be reduced while improving the heat dissipation of the motor unit (14).

[0128] In the motor unit (14) according to the sixth aspect, in the second, third, or fifth aspect, the metal part (7) constitutes the radially inner part of the member (61) that forms the ventilation passage (4).

[0129] According to this aspect, even when many heat-generating components are arranged radially inside the circuit board (57), such as in an inner rotor type motor unit (14), the heat generated from these heat-generating components can be efficiently transferred to the metal part (7) that constitutes the radially inner part of the member (61).

[0130] The motor unit (14) according to a seventh aspect is the motor unit (14) according to the second, third, fifth, or sixth aspect, further including a bearing (521) that rotatably supports the rotor (51). A part of the metal part (7) constitutes a metal holder (75) that holds the bearing (521).

[0131] According to this aspect, the bearing (521) can be firmly supported by the metal holder (75). Moreover, since the holder (75) is part of the metal part (7), an increase in the number of parts is suppressed.

[0132] The blower (1) according to the eighth aspect includes a motor unit (14) according to any one of the first to seventh aspects, a centrifugal fan (2) driven to rotate by a rotor (51), and a fan case (3) that rotatably houses the centrifugal fan (2).

[0133] According to this aspect, heat generated on the circuit board (57) of the motor unit (14) included in the blower (1) is conducted to the metal part (7) and is effectively dissipated through the metal part (7) into the air flowing through the ventilation passage (4). This improves the heat dissipation performance of the motor unit (14). Furthermore, by increasing the input power to the motor unit (14), the output of the blower (1) can be increased. Furthermore, the need for highly heat-resistant circuit components is reduced, which increases design freedom and facilitates cost reduction.

[0134] The blower (1) according to a ninth aspect is the eighth aspect, further including a sub-ventilation passage (45) connected to the ventilation passage (4). The sub-ventilation passage (45) is formed between the motor case (6) and the fan case (3).

[0135] According to this aspect, the flow of air in the ventilation passage (4) can be easily ensured, and therefore, heat can be easily dissipated into the air flowing through the ventilation passage (4).

[0136] In a blower (1) according to a tenth aspect, in the ninth aspect, a hole (60) is formed in the motor case (6) to expose a part of the circuit board (57). The sub-ventilation passage (45) is formed between the fan case (3) and a part of the motor case (6) where the hole (60) is not formed.

[0137] According to this aspect, lead wires can be soldered to the circuit board (57) through the hole (60) in the motor case (6) while the circuit board (57) is in thermally conductive contact with the metal portion (7) that constitutes a part of the motor case (6). Moreover, the secondary ventilation passage (45) is formed so as to avoid the portion of the motor case (6) where the hole (60) is formed. Therefore, foreign matter flowing through the secondary ventilation passage (45) is prevented from entering the motor case (6) through the hole (60).

[0138] In the blower (1) according to an eleventh aspect, in the eighth or ninth aspect, a hole (60) is formed in the motor case (6) to expose a part of the circuit board (57). The hole (60) is covered by the fan case (3).

[0139] According to this aspect, lead wires can be soldered to the circuit board (57) through the hole (60) in the motor case (6) while the circuit board (57) is in thermally conductive contact with the metal portion (7) that constitutes part of the motor case (6). Moreover, the hole (60) in the motor case (6) is covered by the fan case (3). This prevents foreign matter from entering the motor case (6) through the hole (60).

[0140] The moving body (9) according to the twelfth aspect comprises a blower (1) according to any one of the eighth to eleventh aspects, an object (91) to be cooled by the blower (1), and a vehicle body (97) on which the blower (1) and the object (91) to be cooled are mounted.

[0141] According to this aspect, in the blower (1) mounted on the moving body (9), heat generated on the circuit board (57) of the motor unit (14) is conducted to the metal part (7) and is effectively dissipated through the metal part (7) into the air flowing through the ventilation passage (4). This improves the heat dissipation performance of the motor unit (14). Furthermore, by increasing the input power to the motor unit (14), the output of the blower (1) can be increased. This reduces the need to use highly heat-resistant components as circuit components. This increases design freedom and facilitates cost reduction.

[0142] The technology of the present disclosure can be applied to a blower that can improve the heat dissipation performance of a motor unit, and can be widely used in moving objects such as automobiles equipped with a blower.

[0143] REFERENCE SIGNS LIST 1 blower 12 fan unit 14 motor unit 2 centrifugal fan 21 hub 215 connecting portion 216 bottom wall portion 23 blades 3 fan case 30 opening 31 first member 32 second member 33 connecting portion 34 intake port 35 outlet port 36 flow path 37 recess 38 wall portion 380 surface 39 protrusion 4 ventilation path 45 secondary ventilation path 5 electrical mechanism 51 rotor 511 rotor core 514 rotating shaft 521 first bearing 522 second bearing 54 stator 541 stator core 543 winding 56 insulating member 57 circuit board 572 portion 6 motor case 60 hole 601 first hole portion 602 second hole portion 61 first member 62 Second member 622 Outer peripheral edge portion 625 Through hole 628 Holder 63 Heat conduction portion 65 Through hole 7 Metal portion 71 First portion 72 Second portion 73 Third portion 735 Through hole 75 Holder 8 Resin portion 81 Inner peripheral portion 82 Outer peripheral portion 83 Connecting portion 88 Connector housing 9 Mobile body 91 Object to be cooled 92 Battery 93 Wheel 94 Engine 95 Motor 97 Vehicle body

Claims

1. A motor unit for driving a centrifugal fan to rotate, A rotor, a stator facing the rotor; a circuit board configured to control the application of current to the stator; a motor case that houses the rotor, the stator, and the circuit board, the motor case includes a member that forms an air passage between the motor case and the centrifugal fan, At least a part of the member forming the ventilation passage is a heat conductive portion that is in contact with the circuit board so as to be able to conduct heat. Motor unit.

2. The heat conductive portion is a metal portion. The motor unit according to claim 1.

3. an insulating member disposed between the circuit board and the metal portion; the metal portion is in thermally conductive contact with the circuit board via the insulating member; The motor unit according to claim 2.

4. The motor case has a hole formed therein through which a portion of the circuit board is exposed. The motor unit according to claim 2 or 3.

5. The member forming the ventilation passage is composed of the metal part and a resin part provided integrally with the metal part. The motor unit according to claim 2 or 3.

6. The metal portion constitutes a radially inner portion of the member that forms the ventilation passage. The motor unit according to claim 5.

7. a bearing that rotatably supports the rotor; A part of the metal portion constitutes a metal holder that holds the bearing. The motor unit according to claim 2 or 3.

8. The motor unit according to claim 2 or 3; the centrifugal fan that is rotationally driven by the rotor; a fan case that rotatably houses the centrifugal fan, Blower.

9. Further provided is a sub-ventilation passage connected to the ventilation passage, The auxiliary ventilation passage is formed between the motor case and the fan case. The blower of claim 8.

10. a hole is formed in the motor case to expose a portion of the circuit board; The auxiliary ventilation passage is formed between a portion of the motor case where the hole is not formed and the fan case. The blower of claim 9.

11. a hole is formed in the motor case to expose a portion of the circuit board; The hole is covered by the fan case. The blower of claim 9.

12. The blower of claim 8; an object to be cooled by the fan; a vehicle body on which the blower and the object to be cooled are mounted, Mobile object.