Air blower

Abstract

To provide an air blower which comprises a motor and a fan and enables reduction of ingress of minute foreign matters into a bearing of the motor.SOLUTION: An air blower 10 comprising a fan 30 and a motor 50 is provided, the motor 50 has a shaft 51, a bearing 52 supporting the shaft 51, and a motor case 54 covering at least a part of the bearing 52, the fan 30 has a main plate 32 which has a first face 32a opposed to the motor case 54 and a second face 32b with the back opposed to the first face 32a, and is connected to the shaft 51, and a plurality of blades 34 erected from the second face 32b of the main plate 32 and arranged radially with respect to an axial center C of the shaft 51, at least one of the fan 30 and the motor case 54 has shielding members 42, 43, each of the shielding members 42, 43 is arranged between the first face 32a of the main plate 32 and the motor case 54 at a distance from the shaft 51 while encircling the shaft 51.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a blower including a fan and a motor.

Background Art

[0002] Conventionally, blowers have been used for cooling heat-generating equipment. For example, Patent Document 1 discloses a sirocco fan used for cooling an in-vehicle battery. In the sirocco fan described in Patent Document 1, attempts are made to reduce vibration and noise by improving the assembly accuracy of the fan.

[0003] However, in a conventional blower such as that described in Patent Document 1, it has been found that during use, minute foreign matters such as sand and dust are sucked into the bearings of the motor, and the bearings can be damaged by the sucked-in minute foreign matters. If the bearings are damaged in this way, noise is generated and the life of the motor is shortened. In particular, such problems become more prominent when the blower is used in an environment with a lot of dust and sand.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

[0005] The present disclosure has been made to solve such problems, and an object thereof is to provide a blower capable of reducing the intrusion of minute foreign matters into the bearings of a motor.

[0006] To achieve the above object, one aspect of the blower according to the present disclosure is a blower including a fan and a motor, the motor having a shaft including an axis, a bearing supporting the shaft, and a motor case covering at least a part of the bearing. The fan has a first surface facing the motor case and a second surface facing away from the first surface, and includes a main board connected to the shaft and a plurality of blades standing on the second surface of the main board and arranged radially with respect to the axis included in the shaft. At least one of the fan and the motor case has one or more blocking members. The one or more blocking members are located at a distance from the shaft in the radial direction orthogonal to the axis between the first surface of the main board and the motor case and surround the shaft.

[0007] Further, the fan may be attached to the outer surface of the shaft and have a boss for supporting the shaft. The distance between the boss and the motor case is preferably greater than 0 mm and less than or equal to 2.5 mm.

[0008] Further, the one or more blocking members may have an annular shape.

[0009] Further, the one or more blocking members may have a cylindrical shape.

[0010] Further, the one or more blocking members may include a plurality of blocking members having different distances from the axis.

[0011] Further, it is preferable that one or more through-holes penetrating between the first surface and the second surface are formed in the main board between the axis included in the shaft and the region where the plurality of blades stand.

[0012] Further, the one or more blocking members are preferably arranged at a position closer to the shaft than the one or more through-holes. This is preferable.

[0013] Further, the motor case may extend along the direction in which the shaft of the motor extends and have a side surface surrounding the shaft. The one or more blocking members are preferably arranged at a position facing the side surface of the motor case.

[0014] Further, the main board may have a conical surface shape.

[0015] Also, the fan may have one or more blocking members.

[0016] According to the present disclosure, a blower capable of reducing the intrusion of minute foreign matter into the bearings of a motor can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that all the embodiments described below show specific examples of the present disclosure. Therefore, the numerical values, shapes, materials, components, arrangement positions of the components, connection forms, etc. shown in the following embodiments are merely examples and are not intended to limit the present disclosure.

[0019] Note that each figure is a schematic diagram and is not necessarily drawn precisely. Also, in each figure, the same reference numerals are given to substantially the same configurations, and overlapping explanations are omitted or simplified.

[0020] (Embodiment 1) [1-1. Overall Configuration] The overall configuration of the blower 10 according to Embodiment 1 will be described with reference to FIGS. 1 to 3. FIGS. 1 and 2 are a perspective view and a top view showing the appearance of the blower 10 according to Embodiment 1, respectively. FIG. 3 is a cross-sectional view showing the internal structure of the blower 10 according to Embodiment 1. FIG. 3 shows a cross-section taken along line III-III shown in FIG. 2, in other words, a cross-section when the blower 10 is cut by a plane passing through the axis C of the shaft 51 included in the blower 10.

[0021] The blower 10 shown in FIGS. 1 and 2 is a sirocco fan that blows out the gas sucked from the suction port 11 from the blowout port 12. As shown in FIG. 3, the blower 10 includes a case 14, a fan 30, and a motor 50. The blower 10 sucks in the gas from the suction port 11 and blows it out from the blowout port 12 by rotating the fan 30 by the motor 50.

[0022] The case 14 is an instrument that serves as the outer shell of the blower 10 as shown in FIGS. 1 to 3. The ca The casing 14 is formed with a suction port 11 and a blowout port 12. As shown in FIG. 3, a fan 30 and a motor 50 are arranged inside the casing 14. In FIG. 3, the motor 50 is fixed to the bottom of the casing 14. The fan 30 is fixed to a shaft 51 of the motor 50. The suction port 11 formed in the casing 14 is arranged on the axis C (that is, the rotation axis of the motor 50) including the shaft 51. The blowout port 12 is arranged at a position radially separated from the axis C. Here, the radial direction means the direction orthogonal to the axis C. Thereby, the gas sucked from the suction port 11 in the direction along the axis C is blown out from the blowout port 12 in the direction intersecting the axis C.

[0023] The material forming the casing 14 is not particularly limited, and for example, it may be polybutylene terephthalate (PBT), polycarbonate (PC), polypropylene (PP), or a mixture thereof.

[0024] The motor 50 is a device for rotating the fan 30. As shown in FIG. 3, the motor 50 has a shaft 51, a bearing 52, and a motor case 54. The motor 50 further includes a rotor 56 and a stator 58. The motor 50 is not particularly limited as long as it is a motor having a shaft 51, a bearing 52, and a motor case 54, but in the present embodiment, it is an inner rotor type brushless motor.

[0025] The shaft 51 is a columnar member that rotates with respect to the motor case 54. The material forming the shaft 51 is not particularly limited, and for example, it may be a metal such as stainless steel.

[0026] The bearing 52 is a member that supports the shaft 51. The bearing 52 has a substantially cylindrical shape. The inner surface of the bearing 52 is attached to the outer surface of the shaft 51 along the axial center C direction in which the shaft 51 extends. The outer surface of the bearing 52 is fixed to the motor case 54. The bearing 52 can reduce the rotational resistance of the shaft 51 with respect to the motor case 54. As the bearing 52, for example, a sintered oil-impregnated bearing can be used.

[0027] The motor case 54 is a housing that covers at least a part of the bearing 52. The motor case 54 covers a part of the shaft 51, the bearing 52, the rotor 56, the stator 58, etc. The motor case 54 is fixed to the case 14. The material forming the motor case 54 is not particularly limited, and for example, a galvanized steel sheet or the like may be used. In the present embodiment, the motor case 54 includes a top surface 54a, a side surface 54b, a stepped upper surface 54c, a stepped side surface 54d, and a bottom surface 54e.

[0028] The top surface 54a is a surface that faces the first surface 32a of the main board 32 of the fan 30. The top surface 54a is a surface that intersects the axial center C included in the shaft 51. The top surface 54a has a substantially circular shape. The side surface 54b is a surface that extends from the outer edge of the top surface 54a along the direction in which the shaft 51 of the motor 50 extends. The side surface 54b forms an annular shape surrounding the shaft 51 of the motor 50. The side surface 54b has a substantially cylindrical shape. The stepped upper surface 54c extends outward from the end of the side surface 54b far from the fan 30. The stepped upper surface 54c is a surface that faces the first surface 32a of the main board 32 of the fan 30. The stepped upper surface 54c is a flat surface having a substantially annular shape. The stepped side surface 54d is a surface that extends parallel to the shaft 51, which is the rotation axis of the motor 50, from the outer edge of the stepped upper surface 54c. The stepped side surface 54d forms an annular shape surrounding the shaft 51, which is the rotation axis of the motor 50. The stepped side surface 54d has a substantially cylindrical shape. The bottom surface 54e is a surface that covers the region surrounded by the end of the stepped side surface 54d far from the stepped upper surface 54c.

[0029] The rotor 56 is a member that rotates with respect to the stator 58. The rotor 56 is attached to the outer surface of the shaft 51 along the axial center C direction of the shaft 51. It is attached to the outer surface of the shaft 51 along the axial center C direction of the shaft 51.

[0030] The stator 58 is a member that rotates the rotor 56. The stator 58 is disposed around the rotor 56 and fixed to the motor case 54.

[0031] As shown in FIG. 3, the fan 30 is connected to the shaft 51 of the motor 50 and is a component that rotates about the axial center C included in the shaft 51. When the fan 30 rotates in a predetermined direction, a gas flow from the suction port 11 to the blowout port 12 of the blower 10 is generated. The material forming the fan 30 is not particularly limited. However, for example, it may be a resin such as PBT, PC, or PP, or a mixture thereof. The fan 30 is formed of polypropylene containing about 10% by weight of glass fiber.

[0032] Hereinafter, the configuration of the fan 30 will be described with reference to FIGS. 4 and 5 in addition to FIG. 3. FIG. 4 is a first perspective view showing the appearance of the fan 30 according to the first embodiment. FIG. 5 is a second perspective view showing the appearance of the fan 30 according to the first embodiment. As shown in FIGS. 3 to 5, the fan 30 includes a main board 32, a plurality of blades 34, a boss 41, a blocking member 42, and a blocking member 43. The fan 30 further includes an annular member 36 and a reinforcing member 38.

[0033] As shown in FIG. 3, the main board 32 has a first surface 32a facing the motor case 54 and a second surface 32b facing away from the first surface 32a. The main board 32 is a member connected to the shaft 51. The main board 32 is connected to the shaft 51 at its central axis. Here, the central axis of the main board 32 is the rotation axis of the fan 30 and passes through the center of the main board 32. The main board 32 has a conical surface shape. The first surface 32a and the second surface 32b are surfaces located inside and outside the conical main board 32, respectively. At least a part of the motor case 54 is disposed inside the conical space formed by the main board 32.

[0034] On the main board 32, one or more through holes 33 penetrating between the first surface 32a and the second surface 32b are formed between the axis C of the shaft 51 to which the main board 32 is connected and the region where the plurality of blades 34 are erected. More specifically, the one or more through holes 33 are arranged between the region where the boss 41 of the main board 32 is arranged and the region where the plurality of blades 34 are erected. By forming such through holes 33, an assembler assembling the blower 10 can insert a fingertip or the like into the through holes 33 formed in the fan 30. Therefore, the handling of the fan 30 can be facilitated. In addition, the material required to form the fan 30 can be reduced, and the fan 30 can be lightened. Therefore, the power required to rotate the fan 30 can be reduced. In the present embodiment, a plurality of through holes 33 are formed in the main board 32. Thereby, an assembler of the blower 10 can grip the fan 30 using the plurality of through holes 33. Therefore, the handling of the fan 30 can be further facilitated. The number of the through holes 33 is not particularly limited, but in the example shown in FIG. 2, the number of the through holes 33 is six.

[0035] The blade 34 is erected on the second surface 32b of the main board 32. The blade 34 is a plate-like member arranged radially with respect to the axis C (that is, the central axis of the main board 32) included in the shaft 51. The blade 34 may be curved as shown in FIGS. 4 and 5. The plurality of blades 34 are arranged along the outer peripheral edge of the main board 32.

[0036] The annular member 36 is an annular member attached to the end portion on the side opposite to the main board 32 with respect to the plurality of blades 34.

[0037] The boss 41 is attached to the outer surface of the shaft 51 of the motor 50. The boss 41 is a member fixed to the shaft 51. The boss 41 stands on the first surface 32a of the main board 32 It is provided. The boss 41 has a cylindrical shape surrounding the axis C included in the shaft 51. The distance between the boss 41 and the motor case 54 of the motor 50 is greater than 0 mm. Thereby, it is possible to suppress interference between the boss 41 and the motor case 54. Note that the distance between the boss 41 and the motor case 54 means the length of the gap between the boss 41 and the motor case 54.

[0038] Each of the blocking members 42 and 43 is a member that suppresses minute foreign matter such as sand from entering the bearing 52 through between the main board 32 of the fan 30 and the motor case 54. Each of the blocking members 42 and 43 is arranged radially separated from the shaft 51 and surrounding the shaft 51 between the first surface 32a of the main board 32 and the motor case 54. Here, the state where each blocking member surrounds the shaft 51 includes not only the state where each blocking member surrounds the entire circumference of the shaft 51 without interruption, but also the state where each blocking member is arranged around the shaft 51 and a part of each blocking member is interrupted. For example, each blocking member may have a substantially annular shape surrounding the shaft 51, and each blocking member may be separated into a plurality of parts in the circumferential direction with the axis C included in the shaft 51 as the central axis. Each blocking member may be arranged in a range of an angle that exceeds 50% of the total circumferential angle (360°) among the circumferential angles with the axis C included in the shaft 51 as the central axis.

[0039] Each of the blocking members 42 and 43 has an annular shape surrounding the shaft 51. More specifically, as shown in FIG. 5, each of the blocking members 42 and 43 has a cylindrical shape with the rotation axis of the motor 50 (that is, the axis C included in the shaft 51) as the central axis. As shown in FIG. 3, the distances of the blocking members 42 and 43 from the axis C included in the shaft 51 are different from each other. Each of the blocking members 42 and 43 is arranged separated from the outer edge of the main board 32 toward the rotation axis side.

[0040] The reinforcing member 38 is a member that connects to the first surface 32a of the main board 32 and the boss 41. The reinforcing member 38 is a plate-shaped member that extends radially from the axis C included in the shaft 51. Thereby, it is possible to prevent the boss 41 from coming off from the main board 32.

[0041] [1-2. Function] Next, the operation of the blower 10 according to the present embodiment will be described with reference to FIG. 6 while comparing with a comparative example. FIG. 6 is a partial cross-sectional view showing the internal structure of the blower 910 according to the comparative example. FIG. 6 shows a part near the motor 50 and the main board 32 in the cross-section when cut along a plane passing through the axis C of the shaft 51 included in the blower 910.

[0042] As shown in FIG. 6, the blower 910 according to the comparative example includes a case 14, a fan 930, and a motor 50. The case 14 and the motor 50 of the blower 910 according to the comparative example have the same configurations as the case 14 and the motor 50 of the blower 10 according to the present embodiment, respectively.

[0043] The fan 930 included in the blower 910 according to the comparative example has, similarly to the fan 30 according to the present embodiment, a main board 32, a plurality of blades 34, and a boss 141. The main board 32 and the plurality of blades 34 of the fan 930 have the same configurations as the main board 32 and the plurality of blades 34 according to the present embodiment, respectively. The boss 141 is different from the boss 41 according to the present embodiment in the length in the rotational axis direction, that is, the axis C direction, and is the same in other configurations. The boss 141 is shorter in length in the rotational axis direction than the boss 41 according to the present embodiment. For this reason, the distance Gb between the boss 141 and the motor case 54 in the blower 910 according to the comparative example is larger than the distance Gb between the boss 41 and the motor case 54 in the blower 10 according to the present embodiment. Specifically, in the blower 10 according to the present embodiment, the distance Gb is 2 mm, while in the blower 910 according to the comparative example, the distance Gb is 3 mm.

[0044] The fan 930 according to the comparative example also differs from the fan 30 according to the present embodiment in that it does not include the blocking member 42 and the blocking member 43.

[0045] In the blower 910 according to the comparative example, as indicated by the dashed arrow in FIG. 6, minute foreign matters such as sand and dust contained in the gas sucked from the suction port 11 can enter between the main board 32 and the motor 50 through the gap between the fan 930 and the case 14. Minute foreign matters can also enter between the main board 32 and the motor 50 through the through hole 33 formed in the main board 32 of the fan 930. The minute foreign matters that have entered between the main board 32 and the motor 50 can enter the gap between the shaft 51 and the bearing 52 of the motor 50.

[0046] In the blower 910 according to the comparative example, as described above, minute foreign matters can enter between the main board 32 of the fan 930 and the top surface 54a of the motor case 54 of the motor 50. In particular, when the main board 32 has a conical shape, a relatively large space is formed between the main board 32 and the top surface 54a of the motor case 54. Therefore, minute foreign matters are likely to enter between the main board 32 and the top surface 54a of the motor case 54.

[0047] On the other hand, in the blower 10 according to the present embodiment, the fan 30 has a blocking member 42 and a blocking member 43 that are arranged radially apart from the shaft 51 and surround the shaft 51 between the first surface 32a of the main board 32 and the motor case 54. The blocking member 42 and the blocking member 43 can form a narrow portion of the gap between the main board 32 and the motor case 54. Therefore, even when minute foreign matters enter between the main board 32 and the motor 50, at least a part of the minute foreign matters heading toward the shaft 51 and the bearing 52 can be blocked by each blocking member. Therefore, according to the blower 10 according to the present embodiment, the entry of minute foreign matters into the bearing 52 of the motor 50 can be reduced.

[0048] In the present embodiment, each of the blocking members 42 and 43 is disposed at a distance from the outer edge of the main board 32 toward the rotation axis side, that is, the shaft 51 side. Therefore, minute foreign matter can flow into the space sandwiched between each blocking member and the portion outside the blocking member disposed on the main board 32. Accordingly, it is possible to reduce the inflow of minute foreign matter to the rotation axis side from each blocking member.

[0049] Each blocking member has an annular shape surrounding the shaft 51. Thereby, it is possible to reduce the intrusion of minute foreign matter from all directions into the bearing 52 with the axis C included in the shaft 51 as the central axis.

[0050] Each blocking member has a cylindrical shape with the rotation axis of the motor 50 (axis C of the shaft 51) as the central axis. Thereby, since the shape of the fan 30 can be made axisymmetric with respect to the rotation axis of the motor 50, it is possible to reduce vibration and noise during rotation of the fan 30.

[0051] The fan 30 has two blocking members with different distances from the axis C included in the shaft 51. Thereby, even when minute foreign matter passes through the gap between the blocking member 43 with a larger distance from the rotation axis of the motor 50 and the motor case 54, the minute foreign matter can be blocked by the blocking member 42 with a smaller distance from the rotation axis. In other words, even when minute foreign matter passes through the gap between the blocking member 43 with a larger radial distance from the shaft 51 of the motor 50 and the motor case 54, the minute foreign matter can be blocked by the blocking member 42 with a smaller radial distance from the shaft 51.

[0052] Each blocking member is disposed at a position closer to the shaft 51 than the through hole 33. Thereby, it is possible to reduce the intrusion of minute foreign matter that has entered between the main board 32 and the motor 50 from the through hole 33 into the bearing 52.

[0053] In this embodiment, the distance Gb between the boss 41 and the motor case 54 is 2 mm, which is smaller than the distance Gb between the boss 141 and the motor case 54 in the comparative example. Thereby, minute foreign matter that enters between the boss 41 and the motor case 54 can be reduced. Accordingly, minute foreign matter that enters the bearing 52 can be reduced. Note that the distance Gb is not limited to 2 mm. The distance Gb may be greater than 0 mm and about 2.5 mm or less. Thereby, minute foreign matter that enters the bearing 52 can be reduced as compared with the case where the distance Gb is 3 mm as in the blower 910 according to the comparative example.

[0054] [1-3. Analysis Results] Next, in order to confirm the effects of the blower 10 according to this embodiment, the results of analysis using a computer will be described with reference to FIG. 7. FIG. 7 is a diagram showing the analysis results of each blower according to the comparative example and Embodiment 1. FIG. 7 also shows the analysis results of the blowers according to Modifications 1 to 3.

[0055] First, the analysis conditions for each blower according to the comparative example and Embodiment 1 will be described. In this analysis, a fluid analysis of the gas that is sucked into and blown out of each blower was performed. Here, the gas contains particles simulating minute foreign matter, and in the analysis, the positions of the respective particles that move together with the gas were tracked. In this analysis, the volume of the gas sucked by each blower is 100 m 3 / h, and the rotational speed of each fan is 2350 rpm. The density of the particles is 3 mg / mm 3 . The diameters of the particles are distributed within the range of 1 μm or more and 20 μm or less. The number of particles flowing into each blower is 600,000 particles / sec. Under the above conditions, the number of particles that reached a cylinder in the space between the boss of each fan and the motor case 54 in 0.13 sec was defined as the amount of particle intrusion. More specifically, the number of particles that reached the cylindrical space disposed between the boss and the motor case 54 was defined as the amount of particle intrusion. Here, the central axis of the cylindrical space is the rotation axis of the motor 50 (that is, the shaft 51), the diameter is 18 mm, and the height is equal to the distance Gb.

[0056] As shown in FIG. 7, in the blower 910 according to the comparative example, the intrusion amount was 73, while in the blower 10 according to the present embodiment, the intrusion amount was reduced to 5, which corresponds to about 7% of the intrusion amount in the blower 910 according to the comparative example. Thus, it was confirmed that the blower 10 according to the present embodiment can significantly reduce the intrusion amount of minute foreign matters compared to the blower 910 according to the comparative example.

[0057] In the fan 30 according to the present embodiment, compared with the fan 930 according to the comparative example, the length of the boss 41 in the axial center C direction is extended, and with the addition of the blocking member 42 and the blocking member 43, the mass has increased compared to the fan 930 according to the comparative example. FIG. 7 also shows the increase amount of the mass of the fan 30 with respect to the weight of the fan 930 according to such a comparative example. As shown in FIG. 7, the increase amount of the mass of the fan 30 according to the present embodiment with respect to the mass of the fan 930 of the comparative example is 1.8 g. This increase amount corresponds to about 2.65% of the total mass 68 g of the fan 30. Thus, according to the fan 30 according to the present embodiment, it is possible to reduce the intrusion of minute foreign matters into the bearing 52 while suppressing the increase in mass.

[0058] Subsequently, regarding the effects of the respective components according to the present embodiment, an explanation will be given using the analysis results of the respective blowers according to Modification 1 to Modification 3 shown in FIG. 7. The blower according to Modification 1 is a blower in which only the boss 141 of the blower 910 according to the comparative example is replaced with the boss 41 of the blower 10 according to the present embodiment, as shown in the shape column of Modification 1 in FIG. 7. The blower according to Modification 2 is a blower in which only the blocking member 42 of the blower 10 according to the present embodiment is added to the blower 910 according to the comparative example, as shown in the shape column of Modification 2 in FIG. 7. The blower according to Modification 3 is a blower in which only the blocking member 43 of the blower 10 according to the present embodiment is added to the blower 9 10 according to the comparative example, as shown in the shape column of Modification 3 in FIG. 7.

[0059] In the blower according to Modification 1, the amount of intrusion could be reduced to 23, which corresponds to about 32% of the amount of intrusion in the blower 910 according to the Comparative Example. Thus, it was confirmed that reducing the length of the boss 41 according to the present embodiment compared to the boss 141 according to the Comparative Example has the effect of reducing the intrusion of minute foreign matters. The increase in the mass of the fan according to Modification 1 with respect to the mass of the fan 930 of the Comparative Example was 0.1 g. This increase corresponds to about 0.14% of the total mass 68 g of the fan 30. Thus, according to the fan according to Modification 1, it is possible to reduce the intrusion of minute foreign matters into the bearing 52 while suppressing an increase in mass.

[0060] In the blowers according to Modification 2 and Modification 3, the amount of intrusion could be reduced to 16, which corresponds to about 22% of the amount of intrusion in the blower 910 according to the Comparative Example. Further, the increase in the mass of the fan according to Modification 2 is 1.1 g with respect to the mass of the fan 930 of the Comparative Example. This increase corresponds to about 1.62% of the total mass 68 g of the fan 30. The increase in the mass of the fan according to Modification 3 is 0.6 g with respect to the mass of the fan 930 of the Comparative Example. This increase corresponds to about 0.88% of the total mass 68 g of the fan 30. Thus, according to the fans according to Modification 2 and Modification 3, it is possible to reduce the intrusion of minute foreign matters into the bearing 52 while suppressing an increase in mass.

[0061] From the analysis results of the blowers according to Modification 1 to Modification 3, it was confirmed that each of the boss 41, the blocking member 42, and the blocking member 43 according to the present embodiment has the effect of reducing the intrusion of minute foreign matters into the bearing 52. Further, in the present embodiment, it was confirmed that by combining the configurations of these Modification 1 to Modification 3, the effect of reducing the intrusion of minute foreign matters into the bearing 52 can be further enhanced compared to each of Modification 1 to Modification 3.

[0062] As described above, the blower 10 of the present embodiment is a blower 10 including a fan 30 and a motor 50. The motor 50 has a shaft 51 including an axis C, a bearing 52 that supports the shaft 51, and a motor case 54 that covers at least a part of the bearing 52. The fan 30 has a first surface 32a facing the motor case 54 and a second surface 32b facing away from the first surface 32a, and includes a main board 32 connected to the shaft 51 and a plurality of blades 34 erected on the second surface 32b of the main board 32 and arranged radially with respect to the axis C including the shaft 51. At least one of the fan 30 and the motor case 54 has one or more blocking members 42, 43. The one or more blocking members 42, 43 are positioned at a distance from the shaft 51 in the radial direction orthogonal to the axis and surround the shaft 51 between the first surface 32a of the main board 32 and the motor case 54.

[0063] Thereby, it is possible to provide a blower 10 that can reduce the intrusion of minute foreign matter into the bearing 52 of the motor 50.

[0064] Further, the fan 30 may be attached to the outer surface of the shaft 51 and have a boss 41 that supports the shaft 51.

[0065] Further, the motor case 54 may extend along the direction in which the shaft 51 of the motor 50 extends and have a side surface 54b that surrounds the shaft 51.

[0066] (Embodiment 2) The blower according to Embodiment 2 will be described. The blower according to the present embodiment is mainly different from the blower 10 according to Embodiment 1 in the configuration of the blocking member of the fan. The blower according to the following present embodiment will be described mainly focusing on the differences from the blower 10 according to Embodiment 1.

[0067] [2-1. Overall Configuration] First, the overall configuration of the blower according to this embodiment will be described with reference to FIG. 8. FIG. 8 is a partial cross-sectional view showing the internal structure of the blower 110 according to Embodiment 2. FIG. 8 shows a part in the vicinity of the motor 50 and the main board 32 among the cross-sections when cut along a plane passing through the axis C included in the shaft 51 provided in the blower 110.

[0068] As shown in FIG. 8, the blower 110 according to this embodiment includes a case 14, a fan 130, and a motor 50. The case 14 and the motor 50 of the blower 110 according to this embodiment have the same configurations as the case 14 and the motor 50 of the blower 10 according to Embodiment 1, respectively.

[0069] The fan 130 of the blower 110 according to this embodiment has a main board 32, a plurality of blades 34, and a boss 141, similar to the fan 30 according to Embodiment 1. The main board 32 and the plurality of blades 34 of the fan 130 have the same configurations as the main board 32 and the plurality of blades 34 according to Embodiment 1, respectively. The boss 141 has the same configuration as the boss 141 of the fan 930 according to the above-described comparative example. That is, the boss 141 is shorter in the axial direction of the rotation axis of the motor 50, that is, in the direction of the axis C of the shaft 51, than the boss 41 according to Embodiment 1.

[0070] Further, the fan 130 according to this embodiment further includes a blocking member 144. The blocking member 144 is disposed radially apart from the shaft 51 and surrounds the shaft 51 between the first surface 32a of the main board 32 and the motor case 54, similar to each blocking member according to Embodiment 1. The blocking member 144 according to this embodiment is disposed at a position facing the side surface 54b of the motor case 54. Further, the blocking member 144 has an annular shape surrounding the shaft 51. More specifically, the blocking member 144 has a cylindrical shape centered on the rotation axis of the motor 50.

[0071] As shown in FIG. 8, the blocking member 144 is arranged at a position radially farther from the shaft 51 than the through hole 33. Further, the blocking member 144 is arranged at a position radially closer to the shaft 51 than the stepped side surface 54d of the motor case 54.

[0072] [2-2. Operation] Next, the operation of the blower 110 according to the present embodiment will be described with reference to FIG. 8. In the blower 110 according to the present embodiment, since it has the blocking member 144, the same effects as those of the respective blocking members according to the first embodiment are achieved. By arranging the blocking member 144 at a position facing the side surface 54b included in the motor case 54, a labyrinth structure (labyrinth) is formed between the main board 32 of the fan 130 and the motor case 54. By forming such a labyrinth structure, it is possible to reduce the entry of minute foreign matters near the rotating shaft, that is, near the bearing 52.

[0073] The blocking member 144 is arranged at a position radially closer to the shaft 51 than the stepped side surface 54d. As a result, since the blocking member 144 is arranged above the stepped upper surface 54c connected to the stepped side surface 54d, a further labyrinth structure is formed between the stepped upper surface 54c and the blocking member 144. By forming such a labyrinth structure, it is possible to further reduce the entry of minute foreign matters near the rotating shaft, that is, near the bearing 52.

[0074] Since an air flow as indicated by the broken-line arrow in FIG. 8 can be formed in the space sandwiched between the blocking member 144 and the portion outside the blocking member 144 arranged on the main board 32, minute foreign matters can be made to flow into the space. Therefore, it is possible to reduce the entry of minute foreign matters from the side of the blocking member 144 toward the rotating shaft side, that is, the bearing 52 side.

[0075] The blocking member 144 has an annular shape surrounding the shaft 51. Thereby, it is possible to reduce the entry of minute foreign matters toward the bearing 52 from all directions with the axis C included in the shaft 51 as the central axis.

[0076] The blocking member 144 has a cylindrical shape with the rotation axis of the motor 50 as the central axis. In other words, the blocking member 144 has a cylindrical shape with the axis C included in the shaft 51 as the central axis. Thereby, since the shape of the fan 130 can be made axisymmetric with respect to the rotation axis of the motor 50, vibrations and noise during the rotation of the fan 130 can be reduced.

[0077] [2-3. Analysis Results] Next, in order to confirm the effects of the blower 110 according to the present embodiment, the results of analysis using a computer will be described with reference to FIG. 9. FIG. 9 is a diagram showing the analysis results of each blower according to the comparative example and Embodiment 2.

[0078] FIG. 9 shows the results of analysis performed under the same conditions as the analysis conditions of the blower 10 according to the above-described Embodiment 1.

[0079] As shown in FIG. 9, in the blower 910 according to the comparative example, the number of intrusions was 73. On the other hand, in the blower 110 according to the present embodiment, the number of intrusions could be reduced to 44, which corresponds to about 60% of the number of intrusions in the blower 910 according to the comparative example. Thus, it was confirmed that the blower 110 according to the present embodiment can significantly reduce the amount of foreign matter intrusion compared to the blower 910 according to the comparative example.

[0080] (Modification Example) As described above, the electric blower according to the present disclosure has been described based on the embodiments. However, the present disclosure is not limited to the above-described embodiments.

[0081] For example, in each of the above embodiments, the fan has a blocking member. However, the motor case 54 of the motor 50 may have a blocking member, or both the fan and the motor case 54 may each have a blocking member. That is, at least one of the fan and the motor case 54 may have one or more blocking members.

[0082] In the above-described Embodiment 1, the fan 30 had two blocking members 42 and 43. However, the number of blocking members is not limited to two, and may be one or more. For example, as in Modification 2 and Modification 3 shown in FIG. 7, the number of blocking members may be one.

[0083] The fan 30 had two blocking members with different radial distances from the axis C including the shaft 51. However, the fan 30 may have three or more blocking members with different distances from the axis C including the shaft 51. That is, the fan 30 may have a plurality of blocking members with different distances from the axis C including the shaft 51.

[0084] In each of the above-described embodiments, the entire bearing is covered by the motor case. However, only a part of the bearing may be covered. For example, a part of the bearing on the fan side may be exposed to the outside from the motor case.

[0085] In addition, forms obtained by making various modifications that occur to those skilled in the art to the above-described embodiments, or forms realized by arbitrarily combining the components and functions in the embodiments without departing from the spirit of the present disclosure are also included in the present disclosure.

Industrial Applicability

[0086] The technology of the present disclosure can be used, for example, for sirocco fans. In particular, it is useful as a sirocco fan used in an environment with a lot of minute foreign matter, such as a sirocco fan used for cooling in-vehicle batteries.

Explanation of Signs

[0087] 10, 110, 910 Blower 11 Suction Port 12 Outlet 14 Case 30, 130, 930 Fan 32 Main Board 32a First Surface 32b Second Surface 33 Through-Hole 34 Blade 36 annular member 38 reinforcing member 41, 141 boss 42, 43, 144 blocking member 50 motor 51 shaft 52 bearing 54 motor case 54a top surface 54b side surface 54c stepped upper surface 54d stepped side surface 54e bottom surface 56 rotor 58 stator C axis center

Claims

Claim 1 A blower comprising a fan and a motor, wherein the motor has a shaft including an axis, a bearing supporting the shaft, and a motor case covering a part of the bearing, wherein the fan has a first surface facing the motor case and a second surface facing away from the first surface, and a main board connected to the shaft, a plurality of blades standing on the second surface of the main board and arranged radially with respect to the axis included in the shaft, wherein at least one of the fan and the motor case has a plurality of blocking members, wherein one or more through holes penetrating between the first surface and the second surface are formed in the main board between the axis included in the shaft and the region where the plurality of blades stand, wherein the plurality of blocking members are arranged at a position farther from the shaft than the one or more through holes in the radial direction a blower.

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