Motor, air blower, and mobile body

Abstract

To provide a motor, an air blower, and a mobile body, in which further silent is realized.SOLUTION: A motor comprises: a washer assembly 45 arranged between a tip end surface of a metal bearing 35 in a shaft direction A1 and an opposite surface 43 of a rotor. The opposite surface 43 of the rotor includes a concave part 44. The tip end surface of the metal bearing 35 includes: a concave part 46 that includes a convex part edge part 462 that is opposite to the shaft direction A1 to the washer assembly 45; and an edge part 47 that is positioned at a position separated from the washer assembly 45 in the shaft direction A1 from the convex part edge part 462 on an outer peripheral side from the concave part 46. When a diameter of an outer peripheral edge 432 of the concave part 44 is D1, a diameter of the outer peripheral edge of the washer assembly 45 is D2, a diameter of the convex part edge part 462 is d1, and a diameter of the edge part 47 is d2, the following equation is satisfied: D2>d2>D1>d1.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure generally relates to motors, blowers and moving bodies. [Background technology]

[0002] The motor described in Patent Document 1 comprises a shaft (rotating axis), a metal bearing that supports the shaft so that it can rotate freely, a rotor including a rotor frame attached to the shaft along the axial direction of the shaft, and a stator arranged opposite the outer circumferential surface of the rotor with a gap therebetween.

[0003] Conventionally, for example, a technology has been known in which the rotor and the stator are arranged so that the magnetic center of the rotor and the magnetic center of the stator are spaced a predetermined distance from each other in the axial direction of the shaft, and the rotor is supported by utilizing a force that tries to align the magnetic center positions of the rotor and the stator in the axial direction. However, there has been a problem in that when a strong impact is applied to the motor, for example when driving on rough roads, the rotor jumps up and hits a metal bearing or the like, which causes a collision noise.

[0004] In order to solve the above problems, the motor described in Patent Document 1 further includes a washer disposed between the metal bearing and the rotor frame. This allows the washer to bend when a strong impact is applied to the motor, thereby reducing the impact noise, thereby achieving a quiet motor. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2012 / 157159 Summary of the Invention [Problem to be solved by the invention]

[0006] However, even with the motor described in Patent Document 1, for example, it may not be possible to sufficiently reduce the impact noise caused by a large impact. Therefore, there is a demand for further quieter motors.

[0007] The present disclosure has been made in consideration of the above-mentioned points, and an object of the present disclosure is to provide a motor, a blower, and a moving body that realize further noise reduction. [Means for solving the problem]

[0008] A motor according to one aspect of the present disclosure includes a rotating shaft, a bearing, a rotor, a stator, and a buffer member. The rotating shaft has an axis as a rotation center and extends in an axial direction along which the axis extends. The bearing rotatably supports the rotating shaft. The bearing includes a tip surface located at a tip in the axial direction. The rotor is fixed to the rotating shaft and has an opposing surface that faces the tip surface of the bearing in the axial direction. The stator is located opposite the rotor. The buffer member is disposed between the tip surface of the bearing and the opposing surface of the rotor in the axial direction. The opposing surface of the rotor has a recess. The tip surface of the bearing has a convex portion that faces the buffer member in the axial direction, and an annular contact portion that is located on the outer circumferential side of the convex portion and farther from the buffer member than the tip of the convex portion in the axial direction. If the diameter of the outer peripheral edge of the recess is D1, the diameter of the outer peripheral edge of the buffer member is D2, the diameter of the outer peripheral edge of the protrusion is d1, and the diameter of the annular contact portion is d2, then D2>d2>D1>d1 holds at a location corresponding to at least one cross section along a plane including the axis.

[0009] A blower according to one aspect of the present disclosure includes the motor and a centrifugal fan driven by the motor.

[0010] A moving body according to one aspect of the present disclosure includes the blower, an object to be cooled by the blower, and a moving body main body on which the blower and the object to be cooled are mounted. Effect of the Invention

[0011] According to the present disclosure, it is possible to provide a motor, a blower, and a moving body that realize further noise reduction. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view of a blower according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a perspective view of the motor of the blower. [Diagram 3] FIG. 3 is a vertical sectional view of the motor. [Figure 4] FIG. 4 is a partially enlarged view corresponding to region III in FIG. 3, and is a vertical cross-sectional view of the motor impact sound reduction mechanism and its periphery. [Diagram 5] FIG. 5 is a schematic cross-sectional view showing the dimensional relationship between members of the impact sound reduction mechanism of the above. [Figure 6] FIG. 6 is a schematic cross-sectional view showing the first state of the impact sound reduction mechanism. [Figure 7] FIG. 7 is a schematic cross-sectional view showing the second state of the impact sound reduction mechanism. [Figure 8] FIG. 8 is a schematic cross-sectional view showing the third state of the impact sound reduction mechanism. [Figure 9] FIG. 9 is a schematic cross-sectional view showing the fourth state of the impact sound reduction mechanism. [Figure 10] FIG. 10 is a schematic cross-sectional view showing the fifth state of the impact sound reduction mechanism. [Figure 11] FIG. 11 is a schematic cross-sectional view showing a sixth state of the impact sound reduction mechanism. [Figure 12] FIG. 12 is a schematic cross-sectional view showing a fifth state of another impact noise reduction mechanism in the motor of the blower according to the first embodiment of the present disclosure. [Figure 13] FIG. 13 is a schematic diagram of a vehicle according to the second embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, a motor, a blower, and a vehicle according to an embodiment will be described with reference to the drawings. Each figure described in the following embodiment is a schematic diagram, and the ratio of the size and thickness of each component does not necessarily reflect the actual dimensional ratio. Furthermore, the configuration described in the following embodiment is merely an example of the present disclosure. The present disclosure is not limited to the following embodiment, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

[0014] (First embodiment) (1) Basic structure and operation of a blower A blower 1 according to a first embodiment of the present disclosure will be described with reference to FIGS.

[0015] The blower 1 is, for example, a blower for cooling a battery in a vehicle. Specifically, the blower 1 is a centrifugal fan blower.

[0016] As shown in FIGS. 1 and 2, the blower 1 mainly includes a fan case 2, a motor 3, and a centrifugal fan 4.

[0017] The motor 3 and the centrifugal fan 4 are housed inside the fan case 2. The fan case 2 has an intake port 63 for drawing in outside air, an exhaust port 64 for discharging air toward the outside space, and a circulation passage 61 and an exhaust passage 62 which are passages connecting the intake port 63 and the exhaust port 64. The intake port 63 is an intake port for air into the vehicle cabin, for example, and is formed on the axial end face (the end face on the upper side in the figure) of the substantially cylindrical fan case 2 on the side facing the vehicle cabin. The intake port 63 is an opening having a diameter substantially the same as or slightly smaller than that of the centrifugal fan 4, and communicates with the vehicle cabin via a duct (not shown).

[0018] The motor 3 is, for example, an inner rotor type brushless motor. Hereinafter, in this embodiment, the direction in which the axis X1 (FIG. 3) of the rotating shaft 34 of the motor 3 extends is defined as the axial direction A1 (FIG. 3). In addition, in a plane perpendicular to the axial direction A1, the direction perpendicular to the axis X1 is defined as the radial direction, and the direction going around the axis X1 is defined as the circumferential direction.

[0019] The centrifugal fan 4 is a member in which a plurality of blade members are connected at a predetermined interval in the circumferential direction between two opposing annular members, and is connected to the rotating shaft 34 (FIG. 2) of the motor 3 so as to rotate integrally. The blade members can be made of metal or resin. The centrifugal fan 4 rotates at a predetermined speed in the circumferential direction in response to the rotation of the motor 3, thereby drawing in outside air from an intake port 63 and pumping it out. The pumped air moves through a circulation passage 61, further moves through an exhaust passage 62, and is finally exhausted from an exhaust port 64. The exhausted air is then supplied to the battery from the exhaust port 64.

[0020] (2) Fan case Fan case 2 is a hollow member formed by molding resin, has an air intake port 63 on the top surface, and is roughly cylindrical in shape to house motor 3 and centrifugal fan 4. As shown in Figure 1, fan case 2 includes a lower first case 5 and an upper second case 6.

[0021] Specifically, fan case 2 has an upper wall, side wall, and lower wall of circulating passage 61 and exhaust passage 62, and is configured to cover centrifugal fan 4. With this configuration, circulating passage 61 and exhaust passage 62 are formed inside fan case 2 so as to follow the outer periphery of centrifugal fan 4. As shown in Fig. 1, circulating passage 61 is formed so as to surround the outer periphery of centrifugal fan 4, and exhaust passage 62 is linear.

[0022] (3) Motor 2 and 3, the motor 3 will be described. The motor 3 has a motor case 31, a rotor 32, a stator 33, a rotating shaft 34, and a metal bearing 35. The motor 3 is an inner rotor type brushless motor in which the rotor 32 is disposed on the inner peripheral side of the stator 33.

[0023] The motor 3 is connected to the centrifugal fan 4 at one end of a rotating shaft 34, and the centrifugal fan 4 rotates in conjunction with the rotation of the rotating shaft 34.

[0024] The rotor 32 , the stator 33 , and the metal bearing 35 are housed within the motor case 31 .

[0025] The motor case 31 has a case lid 311, a case body 312, and a bottom plate 313. The case lid 311 is fixed to the lower part of the case body 312. The bottom plate 313 is an annular member that is disposed inside the case lid 311 and the case body 312 and fixed to the case body 312. The motor case 31 is made of, for example, an electrolytic galvanized steel sheet.

[0026] The rotating shaft 34 is disposed at the center of the motor case 31. The rotating shaft 34 extends in the axial direction A1, with one end protruding from the case body 312 and the other end supported by the case lid 311 via a thrust plate 38.

[0027] The metal bearing 35 is a cylindrical member. The metal bearing 35 has a tip surface 351 (FIG. 4). An outer peripheral surface 352 of the metal bearing 35 is fixed to the case body cylindrical portion 39 of the case body 312. An inner peripheral surface 353 of the metal bearing 35 is close to or in contact with an outer peripheral surface 341 of the rotating shaft 34, and rotatably supports the rotating shaft 34. The metal bearing 35 is, for example, a sintered oil-impregnated bearing.

[0028] The rotor 32 has a rotor frame 36 and a rotor magnet 37. The rotor frame 36 adhesively holds the rotor magnet 37. The rotor frame 36 is made of, for example, an electrolytic galvanized steel sheet. The rotor magnet 37 is made of, for example, a rare earth bonded magnet.

[0029] As shown in FIG. 3, the rotor frame 36 has an annular portion 41, a cylindrical portion 42, and a mounting portion 40 (FIG. 4). The mounting portion 40 is provided at the center of the rotor frame 36 and fixed to the rotating shaft 34. The annular portion 41 spreads radially from the mounting portion 40 to form an annular shape. The cylindrical portion 42 extends from the outer periphery of the annular portion 41 along the axial direction A1. Thus, the rotor frame 36 has a cup shape with one end side open. The metal bearing 35 is disposed on the open side of the rotor frame 36, and a part of the metal bearing 35 is disposed inside the rotor frame 36. As shown in FIG. 4, the annular portion 41 has an opposing surface 43 that faces the tip surface 351 of the metal bearing 35 in the axial direction A1.

[0030] 3, the stator 33 is mounted on the bottom plate 313 and disposed on the outer periphery of the rotor 32, facing the rotor 32 with a gap therebetween. The stator 33 includes an iron core and a winding wound around the iron core, and forms an electromagnet by passing a predetermined current through the winding. By controlling the magnetic field generated by this electromagnet, the rotor 32 rotates at a desired rotation speed around the rotating shaft 34.

[0031] The thrust plate 38 is disposed on the inner central surface of the case lid 311, and supports the tip portion 342 of the rotating shaft 34 in the axial direction A1. The thrust plate 38 is made of, for example, a resin, such as polyether ether ketone (PEEK).

[0032] The rotor frame 36 and the rotating shaft 34 are movable relative to the metal bearing 35 in the axial direction A1 within a predetermined range.

[0033] The rotor 32 and the stator 33 are arranged such that the magnetic center of the rotor 32 and the magnetic center of the stator 33 are spaced apart by a predetermined distance in the axial direction A1 so that the rotor 32 is biased downward in the axial direction A1 in the figure. As a result, a restoring force F10 is generated, which presses the tip of the rotating shaft 34 against the thrust plate 38.

[0034] (4) Outline of impact sound reduction mechanism As shown in Fig. 4, the motor 3 has a collision sound reduction mechanism 49. The collision sound reduction mechanism 49 is a mechanism for reducing the collision sound between the metal bearing 35 and the rotor frame 36 when the rotor 32 moves in the axial direction A1 due to an impact. The collision sound reduction mechanism 49 mainly has a recess 44 of the rotor frame 36, a protrusion 46 of the metal bearing 35, and a washer assembly 45 (a cushioning member).

[0035] (4-1) Recess As shown in FIG. 4, a recess 44 is provided on the facing surface 43 of the annular portion 41 of the rotor frame 36. The recess 44 is formed so as to provide a step from the surface of the annular portion 41 on the metal bearing 35 side (an outer peripheral surface 431 described later) in a direction away from the metal bearing 35. The recess 44 is also formed so as to form a ring shape of a predetermined width in the radial direction from the inner peripheral edge of the annular portion 41 of the rotor frame 36 when viewed from the axial direction A1. The recess 44 has a bottom surface 441 with a constant depth. The recess 44 further has an inclined portion 442 that is connected to the bottom surface 441 from the outer peripheral surface 431 by a straight line with an inclined cross section. In the facing surface 43, a flat outer peripheral surface 431 is provided on the outer peripheral side of the recess 44. The outer peripheral edge 432 of the inclined portion 442 is connected to the outer peripheral surface 431.

[0036] (4-2) Convex part As shown in FIG. 4, a protruding portion 46 is provided on the tip surface 351 of the metal bearing 35. The protruding portion 46 is a portion that protrudes toward the annular portion 41 (lower side) on the inner circumferential side of the tip surface 351. The protruding portion 46 is annular in plan view from the axial direction A1. The protruding portion 46 has a flat protruding portion tip surface 461. The outer peripheral edge of the protruding portion tip surface 461 is a protruding portion edge portion 462 (outer peripheral edge) that faces the washer assembly 45 in the axial direction A1. An annular flat surface 48 is provided on the outer peripheral side of the protruding portion 46. Furthermore, an edge portion 47 (annular contact portion) is provided on the tip surface 351 of the metal bearing 35. The edge portion 47 faces the washer assembly 45 in the axial direction A1 and is located farther away from the washer assembly 45 in the axial direction A1 than the protruding portion edge portion 462. The edge portion 47 is the outer peripheral edge of the annular flat surface 48 and is connected to the outer peripheral surface of the metal bearing 35 body. The convex edge 462 and edge 47 of the convex portion 46 are circular in plan view. A chamfered portion 463 is provided on the inner periphery of the convex portion 46. The edge 47 has a right angle in cross section, as shown in FIG.

[0037] (4-3) Washer The washer assembly 45 is an annular thin plate with a circular center hole formed therein. The washer assembly 45 is disposed in a gap G between the annular portion 41 of the rotor frame 36 and the tip surface 351 of the metal bearing 35 in the axial direction A1. Specifically, the washer assembly 45 is disposed between the tip surface 351 of the metal bearing 35 and the opposing surface 43 of the rotor 32. The rotating shaft 34 passes through the center hole of the washer assembly 45, and the washer assembly 45 is movable in the axial direction A1 along the rotating shaft 34 in the gap G.

[0038] The washer assembly 45 includes a first washer 451, a second washer 452, and a third washer 453. The first washer 451, the second washer 452, and the third washer 453 are annular members, and the outer circumferential edge and the inner circumferential edge are circular. In FIG. 4, the first washer 451, the second washer 452, and the third washer 453 are arranged in this order from the metal bearing 35 toward the annular portion 41. The first washer 451 and the third washer 453 have the same shape and dimensions. The second washer 452 is thicker and has a smaller outer diameter than the first washer 451 and the third washer 453. The first washer 451, the second washer 452, and the third washer 453 are made of, for example, resin, for example, polyether ether ketone (PEEK). By using multiple washers as described above, the relative speed between first washer 451 and second washer 452, and between second washer 452 and third washer 453 can be reduced, resulting in reduced wear.

[0039] (4-4) Positional relationship between the recess, protrusion and washer As shown in Figures 4 and 5 (in Figure 5, the washer assembly 45 is simplified as a single washer), the outer diameter of the recess 44 of the rotor frame 36 (specifically, the diameter of the outer peripheral edge 432 of the recess 44) is D1, the outer diameter of the washer assembly 45 (specifically, the diameter of the outer peripheral edges of the first washer 451 and the third washer 453) is D2, the diameter of the convex edge portion 462 of the convex portion 46 (the diameter of the outer peripheral edge of the convex portion 46) is d1, and the diameter of the edge portion 47 of the metal bearing 35 is d2.

[0040] In this embodiment, D2 (outer diameter of washer assembly 45)>D1 (outer diameter of recess 44) holds true, so that washer assembly 45 does not fall into recess 44.

[0041] In this embodiment, D1 (outer diameter of recess 44) > d1 (diameter of convex edge 462 of convex portion 46) holds, so that when the rotor frame 36 and the metal bearing 35 approach each other, the convex portion 46 can enter the concave portion 44.

[0042] Furthermore, d2 (diameter of edge 47)>D1 (outer diameter of recess 44) holds, so that edge 47 cannot enter recess 44 even if rotor frame 36 and metal bearing 35 approach each other.

[0043] Furthermore, D2 (outer diameter of washer assembly 45) > d2 (diameter of edge 47) holds, so that when the rotor frame 36 and the metal bearing 35 approach each other, the outer periphery of the washer assembly 45 can come into contact with the edge 47 of the metal bearing 35.

[0044] In this embodiment, in a plan view from the axial direction A1, the outer peripheral edge of the recess 44, the outer peripheral edge of the washer assembly 45, the convex edge 462, and the edge 47 are circular, and D2>d2>D1>d1 holds true over the entire circumference.

[0045] In the axial direction A1, when the depth of the recess 44 is H1 and the height of the protrusion 46 is h1, the relationship h1>H1 holds. It is preferable that the difference between h1 and H1 is greater than the thickness of the washer assembly 45.

[0046] (4-5) Impact sound reduction mechanism function The function of the impact sound reduction mechanism 49 will now be described.

[0047] (4-5-1) Overview When the motor 3 is mounted on an automobile, if an impact occurs due to the automobile traveling on a rough road or over a step, a force greater than or equal to the restoring force F10 may act on the rotating shaft 34 in the opposite direction to the restoring force F10. Then, the rotor 32 jumps up, and a gap is instantaneously generated between the rotating shaft 34 and the thrust plate 38. Then, when the strong force disappears, the rotating shaft 34 is forcibly returned to its original position by the restoring force F10. In this way, when a strong impact is applied to the motor 3, the rotor 32 is shaken in the axial direction A1, and the rotor frame collides with the metal bearing, generating a collision sound. However, in this embodiment, the washer assembly 45 is deflected and deformed to suppress the collision energy, thereby suppressing the peak value of the collision sound.

[0048] Furthermore, because the rotor frame 36 is provided with the recess 44, when the rotor frame 36 collides with the metal bearing 35 via the washer assembly 45, the depression of this recess 44 acts to deflect the inner peripheral side of the washer assembly 45. The above-mentioned action of the recess 44 and the washer assembly 45 gives the washer assembly 45 a spring effect, which reduces the impact between the rotor frame 36 and the metal bearing 35 and suppresses the impact noise when the rotating shaft 34 moves in the opposite direction to the restoring force F10.

[0049] As described above, the washer assembly 45 is composed of three washers. From the viewpoint of reducing the impact noise, it is more effective to make the washer assembly 45 out of resin rather than metal. On the other hand, when the washer assembly 45 is made of resin, its strength is generally lower than that of metal. Therefore, in this embodiment, the washer assembly 45 is composed of multiple washers, so that even if one of the washers is deformed beyond its elastic range, the other washers can suppress the impact noise.

[0050] (4-5-2) Details Next, the collision mechanism will be described in detail with reference to Figures 6 to 11. In this case, too, washer assembly 45 is simply represented as a single washer.

[0051] In FIG. 6, the washer assembly 45 is in a free and flat state, and a gap G exists between the metal bearing 35 and the annular portion 41 of the rotor frame 36 in the axial direction A1.

[0052] From the state shown in Fig. 6, the rotor frame 36 moves upward in relation to the metal bearing 35 due to vehicle vibration or impact, resulting in the state shown in Fig. 7. In Fig. 7, the protruding portion tip surface 461 of the protruding portion 46 of the metal bearing 35 is in contact with the inner peripheral portion of the washer assembly 45.

[0053] From the state shown in FIG. 7, the rotor 32 further moves upward with respect to the metal bearing 35, and as shown in FIG. 8, the washer assembly 45 is deflected in the first mode between the rotor frame 36 and the metal bearing 35. In detail, the inner periphery of the washer assembly 45 is bent so as to be convex downward in cross section by the force acting from the outer periphery 432 while being supported by the convex edge 462. During the above operation, a force F1 acts at instant t1, and it can be seen that the speed v2 of the rotor 32 after the collision is lower than the speed v1 before the collision according to F1t1=mv2-mv1 (the momentum and impulse equation). Note that m is the mass of the rotor 32.

[0054] As the rotor 32 further moves upward with respect to the metal bearing 35, the state shifts to that shown in FIG. 9, and the washer assembly 45 comes into contact with the convex edge 462 of the convex portion 46, the outer peripheral edge 432 of the concave portion 44 of the annular portion 41, and the edge 47, and is deflected in the secondary mode. In detail, the radially intermediate portion of the washer assembly 45 is bent so as to be convex toward the upper side in the figure in cross-sectional view by the force acting from the outer peripheral edge 432 while being supported by the edge 47 and the convex edge 462. This bending direction is opposite to the bending direction of the inner peripheral portion of the washer assembly 45, and tensile stress and compressive stress acting in directions opposite to the compressive stress and tensile stress generated in the inner peripheral portion are generated in the radially intermediate portion. Therefore, the energy absorbed by the washer assembly 45 increases. During the above operation, force F2 acts at instant t2, and because F2t2=mv3-mv2, it can be seen that velocity v3 after collision is lower than velocity v2 before collision.

[0055] As the rotor 32 further moves upward with respect to the metal bearing 35, in the state shown in FIG. 10, the inner periphery of the washer assembly 45 is sandwiched between the protruding end surface 461 of the protruding portion 46 and the bottom surface 441 of the recessed portion 44 (end point collision). This is because, as described above, h1>H1 holds. At this time, the speed v3 is low as described above, so the collision noise is reduced. Particularly in this embodiment, the collision occurs near the center of the motor 3, so the collision noise leaking to the outside can be reduced.

[0056] Repulsion occurs from the state in Fig. 10, and the rotor frame 36 moves away from the metal bearing 35 (towards the bottom of the figure), transitioning to the state in Fig. 11. In the above-mentioned repulsion action, when F3t3=mv4-mv3 (the vector of v4 is in the opposite direction to v3), the velocity v3 before the repulsion is low, so the excitation force F3 hammering the motor structure decreases, and the peak value of the impact sound can be significantly reduced.

[0057] From the state of FIG. 11, the states of FIG. 10, FIG. 9, FIG. 8, and FIG. 7 are reproduced in order, and then the state of FIG. 6 is returned to.

[0058] 9 to 11, the inner circumferential portion and the radially intermediate portion of the washer assembly 45 are bent in opposite directions, and therefore the energy of the impact sound can be absorbed more effectively than in the past. Therefore, compared to the conventional impact sound reduction mechanism consisting of a washer and a recess, the impact sound reduction mechanism 49 of this embodiment can further reduce the impact sound, and as a result, a quiet motor 3 can be realized that does not cause discomfort to the driver or passengers.

[0059] (4-5-3) Other impact noise reduction mechanisms Next, the collision mechanism when another impact sound reduction mechanism is adopted will be described with reference to FIG.

[0060] In addition, the contents explained in the above (4-5-2) using Fig. 6 to Fig. 9 and Fig. 11 are common to other impact sound reduction mechanisms described later. Therefore, the explanation of the operation according to Fig. 6 to Fig. 9 and Fig. 11 is based on the explanation in the above (4-5-2). The explanation below will focus on the operation based on the characteristic structure of other impact sound reduction mechanisms shown in Fig. 12.

[0061] As shown in FIG. 12, another impact sound reduction mechanism 49a has a rotor frame 36a and a metal bearing 35a.

[0062] The depth of the recess 44a included in the rotor frame 36a is H1 (see FIG. 5). The height of the protrusion 46a included in the metal bearing 35a is h1 (see FIG. 5).

[0063] In the state shown in FIG. 12, the inner periphery of the washer assembly 45 is sandwiched between the tip surface 461a of the protrusion 46a and the bottom surface 441a of the recess 44a (end point collision). This state is because h1=H1 holds. At this time, as explained in (4-5-2), the speed v3 is low, so the collision sound is small. In particular, in this embodiment, the collision occurs near the center of the motor 3, so the collision sound leaking to the outside can be reduced.

[0064] Second embodiment A vehicle 51 (mobile body) equipped with the blower 1 according to the first embodiment will be described with reference to FIG.

[0065] As shown in FIG. 13, a vehicle 51 includes a blower 1, a battery 52 (an object to be cooled), a control device 53, a cable 54, a cable 56, and a vehicle body 55 (a main body of a moving object).

[0066] In the example of FIG. 13, vehicle 51 is a four-wheeled hybrid vehicle in which an engine and a driving battery 52 are mounted on vehicle body 55. Note that vehicle 51 is not limited to a hybrid vehicle, and may be an electric vehicle. Vehicle 51 on which blower 1 is mounted is not limited to a four-wheeled vehicle, and may be, for example, a vehicle (automobile) such as a two-wheeled vehicle or a three-wheeled vehicle. Also, the object to be cooled may be a part other than battery 52.

[0067] The vehicle body 55 is provided with the blower 1, a battery 52, a control device 53, a cable 54, and a cable 56.

[0068] Battery 52 is, for example, a lithium ion battery, a nickel metal hydride battery, or the like, and supplies power to blower 1, a drive motor for propelling vehicle 51, and the like.

[0069] The control device 53 is electrically connected to the blower 1 via a cable 54, and controls the blower 1. More specifically, the control device 53 is electrically connected to a motor drive circuit of the blower 1 via a cable 54. The control device 53 also controls the battery 52 via a cable 56. More specifically, the control device 53 controls the power supply from the battery 52 to the blower 1, the drive motor, etc.

[0070] The blower 1 used in the vehicle 51 functions as a cooling fan system to suppress a rise in temperature of the battery 52. ​​When air is blown from the blower 1 to the battery 52, it is sent thereto. This causes the battery 52 to be air-cooled, suppressing a rise in temperature of the battery 52.

[0071] (Modification) Modifications of each configuration of the first embodiment will be described below. The modifications can be appropriately combined with each other.

[0072] In the first embodiment, D2>d2>D1>d1 holds throughout the entire circumference, but D2>d2>D1>d1 may hold only at one or more locations corresponding to a cross section along a plane including the axis X1.

[0073] In the first embodiment, the convex edge 462 (outer peripheral edge) is a continuous annular edge, but a convex portion extending in the circumferential direction may be formed on the outer peripheral edge of the convex portion 46. In that case, the convex portion may be a single convex portion formed around the entire circumference, or a plurality of convex portions lined up in the circumferential direction.

[0074] In the first embodiment, the edge portion 47 (annular contact portion) is a continuous annular edge portion, but the annular contact portion may be a convex portion formed extending in the circumferential direction. In that case, the convex portion may be a single convex portion formed around the entire circumference, or may be a plurality of convex portions arranged in the circumferential direction.

[0075] In the first embodiment, h1>H1 holds, but h1=H1 may hold.

[0076] In other words, it is sufficient that h1≧H1 is satisfied.

[0077] In the first embodiment, the edge portion 47 is formed to form a right angle in cross section, but the edge portion 47 may be rounded in cross section. The metal bearing 35 may have an outer circumferential portion on the outer circumferential side of the edge portion 47.

[0078] In the first embodiment, two of the multiple washers satisfy D2>d2>D1>d1, but one or all of the multiple washers may satisfy the above condition.

[0079] In the first embodiment, the plurality of washers includes washers having different shapes, but all of the plurality of washers may have the same shape.

[0080] Although a plurality of washers are used in the first embodiment, only one washer may be used.

[0081] In the first embodiment, the inner peripheral edge and the outer peripheral edge of the washer are circular in plan view, but a plurality of radially extending recesses and protrusions may be provided along the circumferential direction.

[0082] In the first embodiment, the washer is made of resin, but the washer may be made of metal.

[0083] In the first embodiment, a washer is used as the cushioning member, but a leaf spring or another spring may also be used.

[0084] In the first embodiment, the step portion of the recess 44 from the inner surface of the annular portion 41 is an inclined surface, but it may be a vertical surface or a concave or convex curved surface.

[0085] In the first embodiment, the recess 44 is an empty space, but an elastic member made of resin or rubber may be disposed inside the recess 44. In this case, shock absorption is achieved as well as protection of the washer.

[0086] In the first embodiment, the motor is an inner rotor type brushless motor, but it may be an outer rotor type motor or a motor with brushes.

[0087] In the first embodiment, the motor uses a magnetic restoring force to bias the rotor to one side in the axial direction A1, but the rotor's own weight may also be used.

[0088] (Aspect) The present specification discloses the following aspects.

[0089] A motor (3) according to a first aspect of the present disclosure includes a rotating shaft (34), a bearing (35), a rotor (32), a stator (33), and a buffer member (45). The rotating shaft (34) has an axis (X1) as a rotation center and extends in an axial direction (A1) along which the axis (X1) extends. The bearing (35) rotatably supports the rotating shaft (34) and includes a tip surface (351) located at a tip in the axial direction (A1). The rotor (32) is fixed to the rotating shaft (34) and has an opposing surface (43) that faces the tip surface (351) of the bearing (35) in the axial direction (A1). The stator (33) is located opposite the rotor (32). The buffer member (45) is disposed between a tip end surface (351) of the bearing (35) and an opposing surface (43) of the rotor (32) in the axial direction (A1). The opposing surface (43) of the rotor (32) has recesses (44, 44a). The tip end surface (351) of the bearing (35) has protrusions (46, 46a) that face the buffer member (45) in the axial direction (A1), and an annular contact portion (47) that is located on the outer periphery side of the protrusions (46, 46a) and farther from the buffer member (45) in the axial direction (A1) than the tips of the protrusions (46, 46a). If the diameter of the outer peripheral edge (432) of the recessed portion (44, 44a) is D1, the diameter of the outer peripheral edge of the buffer member (45) is D2, the diameter of the outer peripheral edge (462) of the protruding portion (46, 46a) is d1, and the diameter of the annular contact portion (47) is d2, then D2>d2>D1>d1 holds true at a location corresponding to at least one cross section along a plane including the axis (X1).

[0090] According to this embodiment, the buffer member (45) is disposed between the opposing surface (43) of the rotor (32) and the tip surface (351) of the bearing (35) as described above. Therefore, even if the rotor (32) jumps up due to an impact, the buffer effect of the buffer member (45) reduces the impact noise between the rotor (32) and the bearing (35).

[0091] In particular, according to this embodiment, D1>d1 holds, so that when the rotor (32) and the bearing (35) approach each other, the convex portion (46, 46a) can enter the concave portion (44, 44a). Furthermore, d2>D1 holds, so that even if the rotor (32) and the bearing (35) approach each other, the annular contact portion (47) cannot enter the concave portion (44, 44a). Furthermore, D2>d2 holds, so that when the rotor (32) and the bearing (35) approach each other, the outer periphery of the buffer member (45) can come into contact with the annular contact portion (47) of the bearing (35).

[0092] When the rotor (32) moves toward the bearing (35) due to vibration or impact, first, the convex portions (46, 46a) of the bearing (35) come into contact with the inner peripheral portion of the buffer member (45). Next, the buffer member (45) is deflected in a first mode between the rotor (32) and the bearing (35). In detail, the inner peripheral portion of the buffer member (45) is bent by a force acting from the outer peripheral edge (432) while being supported by the second annular portion (47). Next, the buffer member (45) comes into contact with the outer peripheral edge (462) of the convex portions (46, 46a), the outer peripheral edge (432) of the concave portions (44, 44a), and the annular contact portion (47), and is deflected in a second mode. In detail, the radially intermediate portion of the buffer member (45) is bent by a force acting from the outer peripheral edge (432) while being supported by the annular contact portion (47) and the outer peripheral edge (462). This bending direction is opposite to the bending direction of the inner circumference of the washer assembly 45, and tensile stress and compressive stress acting in directions opposite to the compressive stress and tensile stress generated in the inner circumference are generated in the radially intermediate portion. Therefore, the energy absorbed by the buffer member 45 is increased. As a result, the motor 3 is made quieter.

[0093] In the motor (3) according to the second aspect, when the depth of the recessed portion (44) in the axial direction (A1) is H1 and the height of the protruding portion (46) is h1, the relationship h1>H1 holds.

[0094] According to this embodiment, the inner periphery of the buffer member 45 is sandwiched between the tip end surface 461 of the protrusion 46 and the bottom surface 441 of the recess 44 (end point collision). In this case, the collision occurs near the center of the motor 3, so that the collision sound leaking to the outside can be reduced.

[0095] In the motor (3) according to the third aspect, when the depth of the recessed portion (44a) in the axial direction (A1) is H1 and the height of the protruding portion (46a) is h1, h1=H1 holds.

[0096] According to this embodiment, the inner periphery of the buffer member 45 is sandwiched between the tip end surface 461a of the protrusion 46a and the bottom surface 441a of the recess 44a (end point collision). In this case, the collision occurs near the center of the motor 3, so that the collision sound leaking to the outside can be reduced.

[0097] In the motor (3) according to the fourth aspect, in any of the first to third aspects, the outer circumferential edge (432) of the recessed portion (44, 44a), the outer circumferential edge (45, 45a), the outer circumferential edge (462) of the protruding portion (46), and the annular contact portion (47) are circular in plan view from the axial direction (A1). D2>d2>D1>d1 holds true over the entire circumference.

[0098] According to this aspect, a motor that achieves even quieter operation can be obtained.

[0099] The motor (3) according to a fifth aspect is related to any one of the first to third aspects, in that the buffer member (45) is formed of annular members (451, 452, 453).

[0100] According to this embodiment, by using the annular members (451, 452, 453), a motor (3) that is even quieter can be obtained.

[0101] A blower (1) according to a sixth aspect includes the motor (3) according to any one of the first to third aspects, and a centrifugal fan (4) driven by the motor (3).

[0102] According to this embodiment, a blower (1) that realizes even quieter operation can be obtained.

[0103] A moving body (51) according to the seventh aspect includes a blower (1) according to the sixth aspect, an object to be cooled (52) cooled by the blower (1), and a moving body main body (55) on which the blower (1) and the object to be cooled (52) are mounted.

[0104] According to this embodiment, a moving body (51) that realizes even quieter operation can be obtained. [Explanation of symbols]

[0105] 1: Blower 2: Fan case 3: Motor 4: Centrifugal fan 31: Motor case 32: Rotor 33: Stator 34: Rotation axis 35, 35a: Metal bearing (bearing) 43: Opposite surface 44, 44a: recess 45, 45a: Washer assembly (washer) 46, 46a: convex part 47: Edge (annular contact area) 51: Vehicle (moving object) 52: Battery (object to be cooled) 53: Control device 55: Vehicle body (mobile body) 313: Bottom plate 351:Tip surface 432: Outer edge 451: First washer (annular member) 452: Second washer (annular member) 453: Third washer (annular member) 462: Convex edge (outer periphery) D1: Diameter D2: Diameter X1: Axial center d1 :Diameter d2 :Diameter

Claims

1. A rotation axis having an axis as a rotation center and extending in an axis direction in which the axis extends; a bearing that rotatably supports the rotating shaft and includes a tip surface located at a tip in the axial direction; a rotor fixed to the rotating shaft and having an opposing surface facing the tip surface of the bearing in the axial direction; a stator positioned opposite the rotor; a buffer member disposed between the tip surface of the bearing and the opposing surface of the rotor in the axial direction, The facing surface of the rotor has a recess, The tip surface of the bearing is a protrusion facing the buffer member in the axial direction; an annular contact portion located on the outer circumferential side of the protrusion and farther from the buffer member in the axial direction than a tip of the protrusion, If the diameter of the outer circumferential edge of the recess is D1, the diameter of the outer circumferential edge of the buffer member is D2, the diameter of the outer circumferential edge of the protrusion is d1, and the diameter of the annular contact portion is d2, then: At a location corresponding to at least one cross section along a plane including the axis, D2>d2>D1>d1 is satisfied. Motor.

2. In the axial direction, when the depth of the recess is H1 and the height of the protrusion is h1, h1>H1 holds.

2. The motor according to claim 1.

3. In the axial direction, if the depth of the recess is H1 and the height of the protrusion is h1, then h1=H1 holds.

2. The motor according to claim 1.

4. When viewed from above in the axial direction, the outer circumferential edge of the recess, the outer circumferential edge of the buffer member, the outer circumferential edge of the protrusion, and the annular contact portion are circular in shape, D2>d2>D1>d1 holds true throughout the entire circumference. A motor according to any one of claims 1 to 3.

5. The buffer member is Consisting of an annular member, A motor according to any one of claims 1 to 3.

6. A motor according to any one of claims 1 to 3; and a centrifugal fan driven by the motor. Blower.

7. A blower according to claim 6; An object to be cooled by the blower; and a moving body on which the blower and the object to be cooled are mounted, Mobile body.

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