blower

Abstract

The air blower is provided with a driving unit (2), a shaft (3), a fan (4), and a rotation-stopping member (5). The shaft (3) is rotated by the torque output from the driving unit (2). The fan (4) has a main plate (10) having a shaft hole (11) press-fitted to the shaft (3), a cover (20) provided opposite the main plate (10) and having an air suction port (21) in the center, and a plurality of blades (30) disposed around a shaft core (CL) between the cover (20) and the main plate (10). The rotation-stopping member (5) is fixed to the shaft (3) and the main plate (10) and restricts the relative rotation of the shaft (3) and the fan (4). Furthermore, the main plate (10) has an inclined portion (13) inclined to the driving unit (2) side as it moves away from the shaft hole (11) to the radial outside, and a flat portion (16) provided discontinuously or continuously around the shaft core (CL) at a portion of the inclined portion (13) and perpendicular to the shaft core (CL).

Description

[0001] Cross-referencing of related applications

[0002] This application is based on Japanese Patent Application No. 2020-169959, filed on October 7, 2020, the contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to a blower. Background Technology

[0004] Previously, the blower described in Patent Document 1 was known as a blower. This blower includes: a fan that is pressed into and fixed to a shaft of an electric motor, and a cover that serves as an anti-rotation member that is pressed into and fixed to the end of the shaft and the fan, thereby limiting the relative rotation of the shaft and the fan.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent No. 3997822

[0008] In the assembly process of the blower described in Patent Document 1, the fan and cover are temporarily assembled and pressed into a structure fixed to a shaft. Furthermore, this blower is configured such that the pressing load on the cover relative to the shaft is greater than the pressing load on the fan relative to the shaft. Therefore, when the fan and cover are pressed into the shaft during the assembly process, a load is applied to the axial end face of the cover located on or near the shaft core, potentially causing the fan to tilt relative to the shaft. As the tilt of the fan relative to the shaft increases, the imbalance of the center of gravity increases, and the vibration during fan rotation may increase. Summary of the Invention

[0009] The purpose of this invention is to provide a blower that can suppress the imbalance of the center of gravity and reduce the vibration when the fan rotates.

[0010] According to one aspect of the present invention, a blower includes: a drive unit, a shaft, a fan, and an anti-rotation member. The shaft rotates due to torque output from the drive unit. The fan includes: a main plate having a shaft hole pressed into and fixed to the shaft; a cover disposed opposite to the main plate and having an air intake at its center; and a plurality of blades disposed around a shaft core between the cover and the main plate. The anti-rotation member is fixed to the shaft and the main plate and restricts relative rotation between the shaft and the fan. Furthermore, the main plate of the fan includes: an inclined portion that tilts towards the drive unit side as it moves radially outward from the shaft hole compared to the anti-rotation member; and a flat portion that is intermittently or continuously disposed around the shaft core in a portion of the inclined portion and is perpendicular to the shaft core.

[0011] Therefore, during the assembly process of this blower, when the fan shaft hole is pressed into and fixed to the shaft, a load can be applied to the flat surface using a pressing tool or the like. This flat surface is perpendicular to the fan shaft core (i.e., the center of the fan shaft hole), so the load is applied to the flat surface parallel to the fan and the shaft core from the pressing tool. Furthermore, the flat surface is located radially outward compared to the anti-rotation member, thus suppressing fan tilting during pressing compared to applying a load only to the anti-rotation member. Specifically, when the tolerance of the right angle relative to the shaft core in the anti-rotation member and the tolerance of the right angle relative to the shaft core in the flat surface are the same, applying a load to the flat surface as well as the anti-rotation member suppresses fan tilting during pressing compared to applying a load only to the anti-rotation member. Therefore, this blower can suppress imbalance of the center of gravity during the assembly process and reduce vibration during fan rotation.

[0012] Furthermore, the parenthesized reference symbols used to annotate each constituent element, etc., represent an example of the correspondence between that constituent element, etc., and the specific constituent elements, etc., described in the embodiments described later. Attached Figure Description

[0013] Figure 1 This is a cross-sectional view obtained by cutting the blower of the first embodiment with an imaginary plane including the shaft.

[0014] Figure 2 yes Figure 1 A top view in direction II.

[0015] Figure 3 yes Figure 1 A cross-sectional view along line III-III.

[0016] Figure 4 yes Figure 1 An enlarged view of part IV.

[0017] Figure 5 This is a graph showing the experimental results of measuring the imbalance of the blower in the first embodiment and the blower in the comparative example.

[0018] Figure 6 This is a cross-sectional view obtained by cutting the blower of the second embodiment with an imaginary plane including the shaft.

[0019] Figure 7 yes Figure 6 Top view in direction VII.

[0020] Figure 8 This is a cross-sectional view obtained by cutting the blower of the third embodiment with an imaginary plane including the shaft.

[0021] Figure 9 yes Figure 8 A top view in the IX direction. Detailed Implementation

[0022] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, in the following embodiments, the same or equivalent parts are labeled with the same symbols, and their descriptions are omitted. Additionally, the shapes of the various structures of the blower shown in the accompanying drawings are illustrated schematically for ease of understanding and are not intended to limit the present invention.

[0023] (First Implementation)

[0024] The first embodiment will be described with reference to the accompanying drawings. The blower in this embodiment is a centrifugal blower used in, for example, air conditioning units or ventilation units.

[0025] like Figure 1 and Figure 2 As shown, the blower 1 includes: a drive unit 2, a shaft 3, a fan 4, and an anti-rotation component 5.

[0026] The drive unit 2 has an electric motor that outputs torque when energized. The drive unit 2 is fixed to a housing 6, such as an air conditioning unit. A shaft 3 protruding from the electric motor in the drive unit 2 rotates around the axis of the shaft 3 by the torque output by the electric motor.

[0027] Fan 4 is a centrifugal fan, comprising: a main board 10 formed in a generally disc shape, a cover 20 disposed opposite to the main board 10, and a plurality of blades 30 disposed between the cover 20 and the main board 10 around a shaft core CL of fan 4. Furthermore, the shaft core CL of fan 4 refers to the center of the shaft hole 11 located on the main board 10 of fan 4. The shaft core CL of fan 4 is consistent with the shaft core of shaft 3.

[0028] The cover 20 has a cylindrical portion 22 and an annular portion 23. The cylindrical portion 22 forms an air intake 21, and the annular portion 23 gradually approaches the main board 10 from the portion on the drive portion 2 side of the cylindrical portion 22 toward the radially outward side, and extends radially outward along the main board 10.

[0029] Multiple blades 30 are disposed between the main board 10 and the cover 20. The multiple blades 30 are arranged at predetermined intervals in the rotational direction. The leading edge 31 of the blade 30 is located radially inward compared to the diameter Df of the suction port 21 of the cover 20. One portion 33 of the multiple blades 30 in the axial direction CL is connected to the cover 20, and the other portion 34 in the axial direction CL is connected to the main board 10. That is, the fan 4 of this embodiment is a closed fan in which the main board 10, the cover 20 and the multiple blades 30 are formed as one piece. This fan 4 is integrally formed, for example, by resin injection molding.

[0030] The motherboard 10 is formed in a generally disc-shaped manner. The motherboard 10 has a shaft hole 11 in its central part. The shaft 3 is pressed and fixed into the shaft hole 11 of the motherboard 10. A plurality of fitting recesses 12 are provided around the shaft hole 11 of the motherboard 10 for fitting into the feet 52 of the anti-rotation member 5 described below.

[0031] like Figures 1-3 As shown, the anti-rotation component 5 is fixed to the shaft 3 and the main board 10, and is a component that restricts the relative rotation of the shaft 3 and the fan 4. Furthermore, the anti-rotation component 5 is also referred to as a fan cover. The anti-rotation component 5 has a cylindrical boss portion 51 and multiple feet 52 extending from the boss portion 51 toward the drive portion 2. The surface 53 of the boss portion 51 facing the intake port 21 is formed as a plane perpendicular to the shaft core CL. The boss portion 51 has a central hole 54 at its center for pressing and fixing the shaft 3. The pressing load of the central hole 54 of the boss portion 51 with the shaft 3 is set to be greater than the pressing load of the shaft hole 11 of the main board 10 with the shaft 3. Therefore, the anti-rotation force of the anti-rotation component 5 with the shaft 3 is set to be greater than the anti-rotation force of the fan 4 with the shaft 3.

[0032] The anti-rotation member 5 has multiple feet 52 that engage with multiple fitting recesses 12 provided on the main board 10. Each fitting recess 12 has a first protrusion 55 projecting radially outward from its inner wall and a second protrusion 56 projecting circumferentially from its inner wall. Therefore, during the manufacturing process of the blower 1, it is not necessary to strictly set dimensional accuracy; by deforming the tips of the first and second protrusions 55 and 56 and ensuring that the multiple feet 52 of the anti-rotation member 5 are tightly fitted with the multiple fitting recesses 12, the anti-rotation member 5 and the fan 4 can be temporarily assembled. Thus, during the assembly process of the blower 1, the anti-rotation member 5 and the fan 4 can be pressed and fixed to the shaft 3 while temporarily assembled.

[0033] When the motor serving as the drive unit 2 is energized, the shaft 3 rotates due to the torque output by the drive unit 2. The rotation of the shaft 3 is transmitted to the fan 4 via the anti-rotation member 5, so that the anti-rotation member 5 and the fan 4 rotate together with the shaft 3. When the fan 4 rotates, the air drawn in from the intake port 21 flows through the flow path between the multiple blades 30 and the leading edge 31 of the blades 30, and is blown out radially outward from the air outlet formed between the radially outer end of the cover 20 and the main plate 10 and the trailing edge 32 of the blades 30.

[0034] like Figure 1 , Figure 2 and Figure 4As shown, in the blower 1 of this embodiment, the main board 10 of the fan 4, in addition to the shaft hole 11 and the fitting recess 12 described above, also has an inclined portion 13, a stepped portion 14, multiple protrusions 15, a flat portion 16, and ribs 17. Furthermore, these parts of the main board 10 are integrally formed with resin during the injection molding of the fan 4.

[0035] The inclined portion 13 is a part that is inclined towards the drive portion 2 from the outer side relative to the anti-rotation member 5, as it moves radially outward from the shaft hole 11. In other words, the inclined portion 13 can also be described as a part that is inclined radially inward from the part where the leading edge 31 of the blade 30 is connected to the main plate 10, protruding towards the intake port 21. This inclined portion 13 guides the air drawn in from the intake port 21 toward the flow path formed between the plurality of blades 30.

[0036] The stepped portion 14 is formed on a part of the inclined portion 13. The angle formed between the stepped portion 14 and the shaft core CL is perpendicular. In addition, the stepped portion 14 is formed in a ring shape around the shaft core CL. Furthermore, in this embodiment, the stepped portion 14 is formed closer to the anti-rotation member 5 than closer to the leading edge 31 of the blade 30.

[0037] Multiple protrusions 15 are provided on a portion of the inclined portion 13. Specifically, in this embodiment, three protrusions 15 are provided at predetermined intervals around the axis CL on the stepped portion 14 formed on a portion of the inclined portion 13. Furthermore, in this embodiment, the number of protrusions 15 is set to three, but the number of protrusions 15 can be more than three, and the number can be arbitrarily set.

[0038] Multiple protrusions 15 extend from the stepped portion 14 parallel to the shaft core CL toward the intake port 21. The surface of the protrusion 15 facing the intake port 21 becomes a plane perpendicular to the shaft core CL. In this embodiment, the surface of the protrusion 15 facing the intake port 21 constitutes a planar portion 16. That is, the multiple planar portions 16 formed by the surfaces of the multiple protrusions 15 facing the intake port 21 are planes perpendicular to the shaft core CL, and are intermittently arranged around the shaft core CL in a portion of the inclined portion 13. Furthermore, the multiple planar portions 16 have the same height in the direction of the shaft core CL. In other words, the multiple planar portions 16 are formed on the same imaginary plane perpendicular to the shaft core CL.

[0039] Ribs 17 are provided on the mainboard 10 at locations opposite to the intake port 21, relative to the positions where multiple protrusions 15 are provided. The ribs 17 improve the rigidity of the mainboard 10 where multiple protrusions 15 are provided and the surrounding area therein. Specifically, when a load is applied to the drive unit 2 side of the drive unit 2 on the flat portion 16 of the protrusion 15 facing the intake port 21 side, parallel to the shaft core CL, the ribs 17 prevent the mainboard 10 where multiple protrusions 15 are provided and the surrounding area therein from deforming towards the drive unit 2 side.

[0040] Here, as Figure 1 and Figure 2 As shown, the diameter of the imaginary circle VC centered on the shaft core CL and connected to the center of the flat portion 16, which is the surface facing the intake port 21 among the multiple protrusions 15, is set as Da. The outer diameter of the anti-rotation member 5 is set as Dc. In addition, the diameter of the intake port 21 of the cover 20 is set as Df. At this time, the relationship is Dc < Da < Df. The meaning of this relationship will be explained below.

[0041] In this embodiment, the blower 1, as described above, can be assembled by pressing the anti-rotation member 5 and the fan 4 into the shaft 3 while they are temporarily assembled. At this time, a load is applied to the surface 53 of the anti-rotation member 5 facing the suction port 21 using a pressing tool (not shown), and a load is also applied to the flat portion 16 of the plurality of protrusions 15 facing the suction port 21. As described above, in this embodiment, the diameter Da of the imaginary circle VC connecting the centers of the plurality of flat portions 16 is in the relationship Da > Dc with respect to the outer diameter Dc of the anti-rotation member 5. That is, the flat portion 16 is provided on the outer side compared to the anti-rotation member 5. Therefore, by applying a load to the flat portion 16 as well as the anti-rotation member 5, tilting of the fan 4 during pressing can be suppressed.

[0042] In detail, assume that the tolerance of the right angle relative to the shaft core CL at the surface 53 facing the intake port 21 in the anti-rotation member 5 and the tolerance of the right angle relative to the shaft core CL at the surface 16 are the same. In this case, the tilt angle relative to the shaft core CL caused by the tolerance at the surface 53 facing the intake port 21 in the anti-rotation member 5 is smaller than the tilt angle relative to the shaft core CL of the imaginary circle VC connecting the centers of the plurality of surface portions 16. Therefore, by applying a load to the surface portion 16 as well as the anti-rotation member 5, the tilting of the fan 4 during injection can be suppressed compared to applying a load only to the anti-rotation member 5.

[0043] Furthermore, as described above, ribs 17 are provided on the motherboard 10 at locations opposite to the intake port 21, relative to the portion where the plurality of protrusions 15 are located. Therefore, during the assembly process, when a load is applied parallel to the shaft core CL to the flat portion 16 of the plurality of protrusions 15 facing the intake port 21 using a pressing tool, deformation of the portion of the motherboard 10 where the plurality of protrusions 15 are located and its surrounding area towards the drive unit 2 is suppressed. Thus, since a load is applied to the flat portion 16 parallel to the shaft core CL using a pressing tool, tilting of the fan 4 during pressing can be suppressed.

[0044] Furthermore, assuming that the planar portion 16 is provided radially outward compared to the diameter Df of the suction port 21 of the cover 20, when a load is applied to the planar portion 16 during the pressing of the fan 4, it is foreseeable that the planar portion 16 and its surroundings will deflect towards the drive portion 2. In this case, it becomes difficult to apply a load to the planar portion 16 parallel to the shaft core CL from the pressing tool, and the fan 4 may be pressed into the shaft 3 at an angle.

[0045] In contrast, in this embodiment, the diameter Da of the imaginary circle VC connecting the centers of the plurality of planar portions 16 is in the relationship that Da < Df with respect to the diameter Df of the suction port 21 of the cover 20. That is, the planar portion 16 is provided on the inner side compared to the diameter Df of the suction port 21 of the cover 20. As a result, even when a load is applied to the planar portion 16 when the fan 4 is pressed in, deflection of the planar portion 16 and its surroundings is suppressed. Therefore, the planar portion 16 can be loaded parallel to the pressing tool and the shaft core CL, thereby preventing the fan 4 from tilting during pressing.

[0046] Here, in Figure 5 The experimental results of unbalance measurement using the blower 1 of the first embodiment and the blower of the comparative example are shown. Furthermore, unbalance refers to the deviation of the center of gravity position of the fan 4 when the blower 1 is driven to rotate.

[0047] In the comparative example of the blower used in the experiment, during the assembly process, with the anti-rotation component 5 and the fan 4 temporarily assembled, a load was applied to the surface 53 of the anti-rotation component 5 facing the suction port 21 using a pressing tool to press and fix the anti-rotation component 5 and the fan 4 onto the shaft 3. Furthermore, the comparative example blower has a substantially the same structure as the blower 1 of the first embodiment.

[0048] The blower of the comparative example and the blower 1 of the first embodiment were respectively placed on an imbalance measuring device (not shown), and the imbalance was measured when the motor of the drive unit 2 was driven at the same rotational speed. As a result, it was determined that the blower 1 of the first embodiment reduced the imbalance by 75% compared to the blower of the comparative example. Therefore, it can be said that the blower 1 of the first embodiment has lower vibration compared to the blower of the comparative example.

[0049] The blower 1 of the first embodiment described above can achieve the following effects.

[0050] (1) In the first embodiment, the main board 10 of the fan 4 of the blower 1 has an inclined portion 13 and a flat portion 16. The inclined portion 13 is inclined towards the drive portion 2 as it moves radially outward from the shaft hole 11 compared to the anti-rotation member 5. The flat portion 16 is provided intermittently around the shaft core CL in a portion of the inclined portion 13. The flat portion 16 is a surface perpendicular to the shaft core CL.

[0051] Therefore, during the assembly process of this blower 1, when the shaft hole 11 of the fan 4 is pressed and fixed relative to the shaft 3, a load can be applied to the flat portion 16 using a pressing tool or the like. Since the flat portion 16 is a surface perpendicular to the shaft core CL, a load can be applied to the flat portion 16 parallel to the shaft core CL of the fan 4 and the shaft 3 using a pressing tool. Furthermore, the flat portion 16 is located radially outward compared to the anti-rotation member 5, so the tilting of the fan 4 during pressing can be suppressed compared to applying a load only to the anti-rotation member 5. Therefore, this blower 1 can suppress the imbalance of the center of gravity during the assembly process and reduce vibration when the fan rotates.

[0052] (2) In the first embodiment, the main board 10 of the fan 4 has three or more protrusions 15 provided around the shaft core CL in a portion of the inclined portion 13. The flat portion 16 is the surface of the protrusions 15 facing the suction port 21.

[0053] Therefore, by making the surface of the protrusion 15, which is provided in a part of the inclined portion 13, facing the intake port 21, a flat portion 16 can be formed more easily. Specifically, for example, by machining and correcting the portion of the axial end face (i.e., the flat portion 16) of the protrusion 15 in the mold used in the injection molding of the fan 4, the accuracy of the right angle and flatness of the flat portion 16 relative to the shaft core CL can be improved. That is, multiple flat portions 16 can be formed on the same imaginary plane perpendicular to the shaft core CL more easily.

[0054] (3) In the first embodiment, the main board 10 of the fan 4 has a stepped portion 14 at a portion of the inclined portion 13 that is perpendicular to the angle formed with the shaft core CL. A plurality of protrusions 15 are provided on the stepped portion 14.

[0055] Therefore, during the assembly process, when a load is applied to the flat portion 16 formed on the protrusion 15 by the pressing tool, even if the protrusion 15 and its surrounding area slightly deflect towards the drive portion 2, interference between the tilting portion 13 of the fan 4 and the pressing tool can be prevented. Thus, by applying a load parallel to the shaft core CL on the flat portion 16 formed on the protrusion 15 by the pressing tool, tilting of the fan 4 during pressing can be prevented.

[0056] (4) In the first embodiment, the stepped portion 14 of the main board 10 of the fan 4 is formed in a ring around the shaft core CL.

[0057] Therefore, the mold used in the injection molding of the fan 4 can be simplified and the stepped portion 14 can be formed more easily. In addition, compared with the structure that assumes that the stepped portion 14 is formed intermittently around the shaft core CL, the air resistance when the fan rotates can be reduced by forming the stepped portion 14 in a ring shape around the shaft core CL.

[0058] (5) In the first embodiment, the main board 10 of the fan 4 has a rib 17 on the side opposite to the suction port 21 relative to the part where the protrusion 15 is provided.

[0059] Therefore, during the assembly process, the rib 17 can prevent the protrusion 15 and its surrounding area from deforming toward the drive section 2 when a load is applied to the flat portion 16 formed on the protrusion 15 by the pressing tool. Thus, a load can be applied to the flat portion 16 formed on the protrusion 15 parallel to the shaft core CL by the pressing tool, and tilting of the fan 4 during pressing can be prevented.

[0060] (6) In the first embodiment, the diameter Da of the imaginary circle VC that connects the centers of the plurality of planar portions 16 is related to the outer diameter Dc of the anti-rotation member 5 as Da > Dc.

[0061] Therefore, by applying a load to the flat portion 16 as well as the anti-rotation member 5, the tilting of the fan 4 during insertion can be suppressed compared to applying a load only to the anti-rotation member 5. Specifically, it is assumed that the tolerance of the right angle relative to the shaft core CL at the surface 53 facing the suction port 21 in the anti-rotation member 5 is the same as the tolerance of the right angle relative to the shaft core CL at the flat portion 16. In this case, the tilt angle relative to the shaft core CL relative to the imaginary circle VC connecting the centers of the plurality of flat portions 16 is smaller than the tilt angle relative to the shaft core CL caused by the tolerance at the surface 53 facing the suction port 21 in the anti-rotation member 5. Therefore, by applying a load to the flat portion 16 as well as the anti-rotation member 5, the tilting of the fan 4 during insertion can be suppressed compared to applying a load only to the anti-rotation member 5.

[0062] (7) In the first embodiment, the diameter Da of the imaginary circle VC connecting the centers of the plurality of planar portions 16 is related to the diameter Df of the suction port 21 of the cover 20 as Da < Df.

[0063] Therefore, even when a pressing load is applied to the flat portion 16 during the pressing of the fan 4, deflection of the flat portion 16 and its surroundings is suppressed. Thus, since a load can be applied to the flat portion 16 parallel to the shaft core CL from the pressing tool, tilting of the fan 4 during pressing can be prevented.

[0064] (Second Implementation)

[0065] The second embodiment will be described. The second embodiment differs from the first embodiment in that a portion of the structure of the fan 4 is changed, while the rest is the same as the first embodiment. Therefore, only the parts that differ from the first embodiment will be described.

[0066] like Figure 6 and Figure 7 As shown, in the second embodiment, no stepped portion is provided on the mainboard 10 of the fan 4. Therefore, multiple protrusions 15 are directly provided on a portion of the inclined portion 13 of the mainboard 10 of the fan 4. In the second embodiment, the number of protrusions 15 is also set to three, but the number of protrusions 15 can be more than three, and the number can be arbitrarily set. The three protrusions 15 are arranged at predetermined intervals around the shaft core CL.

[0067] Multiple protrusions 15 extend from the inclined portion 13 parallel to the shaft core CL toward the intake port 21. The surface of the protrusion 15 facing the intake port 21 is a plane perpendicular to the shaft core CL. In the second embodiment, the surface of the protrusion 15 facing the intake port 21 also constitutes a planar portion 16. These multiple planar portions 16, formed by the surfaces of the multiple protrusions 15 facing the intake port 21, are planes perpendicular to the shaft core CL and are intermittently arranged around the shaft core CL in a portion of the inclined portion 13. Furthermore, the multiple planar portions 16 have the same height in the direction of the shaft core CL. In other words, the multiple planar portions 16 are formed on the same imaginary plane perpendicular to the shaft core CL.

[0068] Ribs 17 are provided on the part of the main board 10 opposite to the suction port 21, opposite to the part where the multiple protrusions 15 are provided. The ribs 17 improve the rigidity of the part of the main board 10 where the multiple protrusions 15 are provided and the surrounding area. That is, during the assembly process, when a load is applied to the flat part 16 formed on the protrusions 15 by a pressing tool, the ribs 17 can prevent the protrusions 15 and the surrounding area from deforming towards the drive part 2.

[0069] Furthermore, in the second embodiment, the diameter Da of the imaginary circle VC connecting the centers of the plurality of planar portions 16 is in a relationship of Dc < Da with respect to the outer diameter Dc of the anti-rotation member 5. Therefore, when the fan 4 is pressed in, by applying a load to the planar portions 16 as well as applying a load to the anti-rotation member 5, tilting of the fan 4 during pressing can be suppressed. Additionally, the diameter Da of the imaginary circle VC connecting the centers of the plurality of planar portions 16 is in a relationship of Da < Df with respect to the diameter Df of the suction port 21 of the cover 20. Therefore, even when a load is applied to the planar portions 16 during the pressing in of the fan 4, deflection of the planar portions 16 and their surroundings can be suppressed.

[0070] The blower 1 of the second embodiment described above can also achieve the same effect as the first embodiment.

[0071] Furthermore, in the second embodiment, during the assembly process, if the protrusion 15 and its surrounding area deform concavely towards the drive portion 2 when a load is applied to the protrusion 15 from the pressing tool, the radially inner portion of the inclined portion 13 of the mainboard 10 compared to the protrusion 15 may interfere with the pressing tool. However, in this case, if the axial height of the protrusion 15 is increased or the rigidity of the rib 17 is increased, interference between the radially inner portion of the inclined portion 13 of the mainboard 10 compared to the protrusion 15 and the pressing tool is prevented, and therefore there is no problem. Therefore, in the structure of the second embodiment, a load can also be applied from the pressing tool parallel to the flat portion 16 formed on the protrusion 15 and the shaft core CL, preventing the fan 4 from tilting during pressing.

[0072] (Third Implementation)

[0073] The third embodiment will be described. The third embodiment differs from the first and second embodiments in that a portion of the structure of the fan 4 is modified; otherwise, it is the same as the first and second embodiments. Therefore, only the parts that differ from the first and second embodiments will be described.

[0074] like Figure 8 and Figure 9 As shown, in the third embodiment, the protrusion 15 is not provided on the mainboard 10 of the fan 4. Instead, the mainboard 10 of the fan 4 has a stepped portion 14 on a portion of the inclined portion 13. The angle formed between the stepped portion 14 and the shaft core CL is perpendicular. In addition, the stepped portion 14 is formed in a ring shape around the shaft core CL. In the third embodiment, the stepped portion 14 provided on a portion of the inclined portion 13 of the mainboard 10 of the fan 4 constitutes a flat portion 16 perpendicular to the shaft core CL. That is, the flat portion 16 of the third embodiment is continuously provided on a portion of the inclined portion 13 around the shaft core CL.

[0075] Ribs 17 are provided on the mainboard 10 at locations opposite to the suction port 21, opposite to the location where the stepped portion 14 is provided. The ribs 17 increase the rigidity of the area where the stepped portion 14 is provided and its surroundings on the mainboard 10. That is, during the assembly process, when a load is applied to the stepped portion 14 from a pressing tool, the ribs 17 prevent the stepped portion 14 and its surroundings from deforming towards the drive unit 2.

[0076] Furthermore, in the third embodiment, the diameter Da of the imaginary circle VC connecting the center of the flat portion 16, which is formed as the step portion 14, is in a relationship of Dc < Da with respect to the outer diameter Dc of the anti-rotation member 5. Therefore, when the fan 4 is pressed in, by applying a load to the flat portion 16 as well as the anti-rotation member 5, the tilting of the fan 4 during pressing can be suppressed. Additionally, the diameter Da of the imaginary circle VC connecting the center of the flat portion 16, which is formed as the step portion 14, is in a relationship of Da < Df with respect to the diameter Df of the suction port 21 of the cover 20. Therefore, even when a load is applied to the flat portion 16 during the pressing of the fan 4, deflection of the flat portion 16 and its surroundings is suppressed.

[0077] The blower 1 of the third embodiment described above can also achieve the same effect as the first and second embodiments. That is, by using the stepped portion 14 provided on a portion of the inclined portion 13 of the main board 10 as the flat portion 16, the blower 1 can suppress tilting when the fan 4 is pressed in. Therefore, the structure of the blower 1 of the third embodiment can also suppress the imbalance of the center of gravity during the assembly process and reduce the vibration when the fan rotates.

[0078] (Other implementation methods)

[0079] (1) In the first and second embodiments described above, the planar portion 16 is a surface of the plurality of protrusions 15 facing the suction port 21 that is perpendicular to the shaft core CL, but the present invention is not limited to such a structure. For example, the planar portion 16 may also be an imaginary plane in which the ends of the protrusions 15 are rounded and the vertices of the plurality of protrusions are connected.

[0080] (2) In the first and second embodiments described above, the shape of the plurality of protrusions 15 provided on the main board 10 of the blower 1 is cylindrical, but not limited thereto. For example, the shape of the protrusions 15 may also be square columnar, or it may be fan-shaped or annular with the shaft core CL as the center when viewed axially.

[0081] (3) In the first and second embodiments described above, a plurality of protrusions 15 are provided at approximately equal intervals around the shaft core CL on a portion of the inclined portion 13 of the main board 10 of the blower 1, but not limited thereto. For example, the plurality of protrusions 15 may also be provided at unequal intervals.

[0082] (4) In the first and third embodiments described above, a step portion 14 is formed in a ring shape on a portion of the inclined portion 13 of the main board 10 of the blower 1, but it is not limited to this. For example, the step portion 14 may be formed intermittently in the circumferential direction with the shaft core CL as the center.

[0083] (5) In the above embodiments, the assembly method of pressing the fan 4 and the anti-rotation component 5 into the shaft 3 in a temporary assembly state has been described, but it is not limited to this. For example, the fan 4 and the anti-rotation component 5 may be pressed into the shaft 3 separately.

[0084] (6) In the above embodiments, the fan 4 and the anti-rotation component 5 are configured as different components, but are not limited thereto. For example, the fan 4 and the anti-rotation component 5 may also be configured as one unit.

[0085] (7) In the above embodiments, the drive unit 2 has been described as having an electric motor, but it is not limited thereto. Various drive devices with output torque can be used as the drive unit 2.

[0086] This invention is not limited to the embodiments described above, and can be appropriately modified. Furthermore, the above embodiments are not unrelated to each other, and can be appropriately combined except in cases where they are clearly incompatible. Additionally, in each of the above embodiments, the elements constituting the embodiment are not necessarily essential, except where explicitly stated as particularly necessary or where they are clearly considered essential in principle. Furthermore, in each of the above embodiments, when referring to the number, value, quantity, range, etc., of the constituent elements of the embodiment, the number is not limited to that specific number, except where explicitly stated as particularly necessary or where it is clearly limited to a specific number in principle. Furthermore, in each of the above embodiments, when referring to the shape, positional relationship, etc., of the constituent elements, the shape, positional relationship, etc., are not limited to that shape, positional relationship, etc., except where specifically stated or where it is limited to a specific shape, positional relationship in principle.

Claims

1. A blower, characterized in that, have: Drive unit; A shaft that rotates due to the torque output by the drive unit; A fan having: a main board having a shaft hole pressed into and fixed to the shaft; a cover disposed opposite to the main board and having an air intake in the center; and a plurality of blades disposed between the cover and the main board around the shaft. as well as An anti-rotation component, fixed to the shaft and the main board, restricts the relative rotation of the shaft and the fan. The motherboard has: An inclined portion, which is inclined towards the drive portion side as it moves radially outward from the shaft hole compared to the anti-rotation member; and Three or more protrusions protrude from a portion of the inclined portion toward the inlet side and are intermittently arranged around the axis. The planar portion of the surface facing the inlet side of one or more of the aforementioned protrusions is formed on the same imaginary plane perpendicular to the shaft core. The planar portion of each of the three or more protrusions is a surface that bears the load applied to the drive portion side in a direction parallel to the shaft core when the shaft hole of the motherboard is pressed into the shaft.

2. The blower according to claim 1, characterized in that, The motherboard has a stepped portion, which is formed at a right angle to the shaft core on a part of the inclined portion. The protrusion is provided such that it protrudes from the stepped portion toward the inlet side.

3. The blower according to claim 1, characterized in that, The main board has ribs on the side opposite to the suction port, relative to the location where the protrusion is provided.

4. The blower according to any one of claims 1 to 3, characterized in that, When the diameter of an imaginary circle connecting the centers of the multiple planar portions and centered on the shaft core is set as Da, and the outer diameter of the anti-rotation component is set as Dc, The relationship Da > Dc is satisfied.

5. The blower according to any one of claims 1 to 3, characterized in that, When the diameter of an imaginary circle connecting the centers of the plurality of planar portions and centered on the axis is set as Da, and the diameter of the suction port of the cover is set as Df, The relationship Da < Df is satisfied.

6. The blower according to any one of claims 1 to 3, characterized in that, When the diameter of an imaginary circle connecting the centers of the plurality of planar portions and centered on the shaft is set as Da, the outer diameter of the anti-rotation member is set as Dc, and the diameter of the suction port of the cover is set as Df, The relationship Dc < Da < Df is satisfied.

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