MOTOR, BLOWING DEVICE, AND CLEANER

A motor includes a shaft disposed along a central axis, a rotor fixed to the shaft and capable of rotating around the central axis, a stator outside of the rotor, a first housing including a cylindrical portion and disposed on an outside of the stator, and a second housing disposed on an upper side of the first housing. The second housing includes a top plate and projected portions extending downward and spaced apart. Ribs extending from both end portions of the projected portion in the circumferential direction to an inside in the radial direction as viewed in the axial direction are disposed on a lower surface of the top plate.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to Japanese Patent Application No. 2017-191041 filed on Sep. 29, 2017. The entire contents of this application are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present disclosure relates to a motor, a blowing device, and a cleaner.

2. Description of the Related Art

A technique for realizing a high speed and large torque of an electric machine having a rotor, such as an electric motor or a generator is known. The electric motor has a rotor including a shaft and an iron core wound around the shaft. Two shields facing each other with the iron core interposed therebetween are members formed in a disc shape and form a casing of the electric motor together with a frame. A through-hole is provided at a center of the shield to allow the shaft to penetrate therethrough and a housing for storing a bearing or the like is provided on an inner surface (surface on an iron core side) of the shield so as to surround the through-hole. Ribs for increasing the rigidity of the shield are provided on the inner surface of the shield. Specifically, eight ribs radially extending from the housing in a direction of an outer periphery are provided in the shield.

In the electric motor, a plurality of the ribs radially extending in the direction of the outer periphery are disposed at equal intervals in a circumferential direction about the shaft. A shape of the casing configuring an outside of the motor varies depending on the application of the motor. Therefore, even if the rigidity of the casing to which the ribs is applied is improved, vibration of the casing may not be appropriately suppressed depending on the shape of the casing.

SUMMARY OF THE INVENTION

A motor according to an exemplary embodiment of the disclosure includes a shaft that is disposed along a central axis extending in a vertical direction; a rotor that is fixed to the shaft and is capable of rotating around the central axis; a stator that is disposed outside of the rotor in a radial direction; a first housing that includes a cylindrical portion extending in an axial direction and disposed on an outside of the stator in the radial direction; and a second housing that is disposed on an upper side of the first housing. The second housing includes a top plate expanding in a direction orthogonal to the central axis, and a plurality of projected portions extending downward from an outer edge of the top plate and spaced apart in a circumferential direction. A plurality of first ribs, which extend from both end portions of the projected portion in the circumferential direction to an inside in the radial direction as viewed in the axial direction, are disposed on a lower surface of the top plate.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, exemplary embodiments of the disclosure will be described in detail with reference to the drawings. In this specification, when describing a motor and a blowing device, a direction parallel to a central axis C of a motor1illustrated inFIG. 3is referred to as an “axial direction”, a direction orthogonal to the central axis C of the motor1is referred to as a “radial direction”, and a direction along a circular arc with the central axis C of the motor1as a center is referred to as a “circumferential direction”. In addition, in this specification, the axial direction is a vertical direction and in the motor1, a shape and a positional relationship of each portion will be described with a side of a second housing50upward with respect to a first housing40. The vertical direction is simply used for explanation and does not limit a positional relationship and direction in an actual positional relationship.

In this specification, when describing a cleaner200, the shape and the positional relationship of each portion will be described with a direction approaching a floor surface F (surface to be cleaned) ofFIG. 11as “downward” and a direction away from the floor surface F as “upward”. These directions are merely used for explanation and do not limit the actual positional relationship and the directions.

In addition, in this specification, an “upstream” and a “downstream” when an impeller110of a blowing device100illustrated inFIG. 9is rotated respectively indicate upstream and downstream in a circulating direction of a fluid drawn in from a cover suction port121.

FIG. 1is a perspective view of the motor1according to the embodiment of the disclosure.FIG. 2is an exploded perspective view of the motor1of the embodiment of the disclosure.FIG. 3is a vertical sectional view of the motor1according to the embodiment of the disclosure. As illustrated inFIGS. 1 to 3, the motor1includes a shaft10, a rotor20, a stator30, the first housing40, and the second housing50. Furthermore, the motor1includes a lower lid60, a bearing70, and a circuit board80.

The shaft10is disposed along the central axis C which vertically extends. The shaft10is a columnar member made of, for example, metal.

The rotor20is fixed to the shaft10and is capable of rotating around the central axis C. As illustrated inFIG. 3, specifically, the rotor20includes a magnet21, an upper fixing member22, and a lower fixing member23. The magnet21has a cylindrical shape is fixed to the shaft10. In a surface of the magnet21on an outside in a radial direction, an N pole and an S pole are alternately arranged in a circumferential direction. The upper fixing member22and the lower fixing member23are cylindrical. The upper fixing member22and the lower fixing member23are fixed to the shaft10to sandwich the magnet21from above and below.

The stator30is outside of the rotor20in the radial direction. As illustrated inFIG. 3, specifically, the stator30includes a stator core31, an upper insulator32, a lower insulator33, and a coil34. The stator core31includes an annular core back portion31aand a plurality of teeth portions31bextending from the core back portion31ato an inside in the radial direction. The core back portion31ais annular around the central axis C. The plurality of the teeth portions31bare disposed at equal intervals in the circumferential direction. The stator core31may be configured by joining a plurality of core pieces. The stator core31may be configured by machining by stacking a plurality of magnetic steel plates.

The upper insulator32is an insulating member that covers a part of an upper surface and a side surface of the stator core31. The lower insulator33is an insulating member that covers a part of a lower surface and the side surface of the stator core31. The upper insulator32and the lower insulator33sandwich the teeth portions31bin the axial direction. The upper insulator32and the lower insulator33cover each of the plurality of the teeth portions31b. The coil34is configured by winding a conductive wire around the upper insulator32and the lower insulator33in each of the teeth portions31b. That is, the insulators32and33are interposed between the teeth portions31band the coil34. Therefore, the teeth portions31band the coil34are electrically insulated from each other.

The first housing40is a lidded cylindrical container for accommodating the rotor20and the stator30. The first housing40is made of, for example, metal. The first housing40opens downward. The first housing40includes a cylindrical portion41and an upper lid portion42. The cylindrical portion41extends in the axial direction. The cylindrical portion41is disposed on an outside of the stator30in the radial direction. That is, the first housing40includes the cylindrical portion41extending in the axial direction and disposed on the outside of the stator30in the radial direction. As illustrated inFIG. 2, the cylindrical portion41includes a plurality of recess portions41awhich are recessed downward. The plurality of the recess portions41aare disposed at equal intervals in the circumferential direction. The upper lid portion42expands in a direction orthogonal to the axial direction and has a disk shape. The upper lid portion42includes a cylindrical upper bearing holding portion42aprotruding upward at a center portion.

The second housing50is disposed on an upper side of the first housing40. The second housing50is made of, for example, resin. The second housing50is fixed to the first housing40by a fixing member2. In the embodiment, the fixing member2is a screw. However, the fixing member2is not limited to the screw, but may be a rivet or the like. In the embodiment, screw holes42bfor fixing screws2are provided in the upper lid portion42of the first housing40. The second housing50has a structure that guides a fluid from the outside of the motor1to the inside of the first housing40. Details of the second housing50will be described later.

The lower lid60is attached to a lower end of the first housing40. The lower lid60is a plate-like member made of, for example, metal. The lower lid60has a cylindrical lower bearing holding portion61protruding downward. The lower lid60has a plurality of lower lid through-holes62penetrating in the axial direction. The plurality of the lower lid through-holes62are disposed at equal intervals in the circumferential direction.

Specifically, the bearing70includes an upper bearing70adisposed on an upper side of the rotor20and a lower bearing70bdisposed on a lower side of the rotor20. The upper bearing70ais held by the upper bearing holding portion42aprovided in the upper lid portion42. The lower bearing70bis held by the lower bearing holding portion61provided in the lower lid60. In the embodiment, each of the bearings70aand70bis a ball bearing. An outer ring of each of the bearings70aand70bis fixed to an inner peripheral surface of each of the holding portions42aand61. An inner ring of each of the bearings70aand70bis fixed to an outer peripheral surface of the shaft10. Therefore, the shaft10and the rotor20are supported to be capable of rotating with respect to the stator30.

The circuit board80is disposed on a lower side of the lower lid60. The circuit board80is fixed to the lower lid60with a predetermined distance by using a plurality of spacers81. The circuit board80has a cylindrical shape and is formed by, for example, resin such as epoxy resin. Electronic components are disposed on the circuit board80. The electronic components include, for example, an inverter and a control circuit. The circuit board80is electrically connected to the stator30by connection terminals (not illustrated).

When electric power is supplied from an electric power source to the coil34via the inverter, magnetic flux is generated in the plurality of the teeth portions31b. A torque in the circumferential direction is generated by an operation of the magnetic flux between the teeth portions31band the magnet21. As a result, the rotor20and the shaft10rotate about the central axis C.

FIG. 4is a perspective view of the second housing50as viewed from the lower side. As illustrated inFIGS. 1 to 4, the second housing50includes a top plate51and a projected portion53. The second housing50further includes an annular portion52.

The top plate51expands in a direction orthogonal to the central axis C. The top plate51has a circular shape as viewed in the axial direction. In the embodiment, the top plate51has an upper recess portion51athat is recessed downward in the axial direction on an upper surface side. The upper recess portion51ahas a circular shape as viewed in the axial direction. The top plate51has the lower recess portion51bthat is recessed upward in the axial direction on a lower surface side. The lower recess portion51bhas a circular shape as viewed in the axial direction. The top plate51has a shaft hole51cpenetrating in the axial direction at a center portion. When the second housing50is disposed on the first housing40, the shaft10passes through the shaft hole51c. The top plate51has an inclined portion51dof which a width in the radial direction increases from an upper side to a lower side at an outer edge. Specifically, the inclined portion51dis configured of a curved surface.

The annular portion52is disposed on the outside of the top plate51in the radial direction. The annular portion52has an annular shape as viewed in the axial direction. A center of the annular portion52coincides with a center of the top plate51as viewed in the axial direction. The central axis C passes through the center. A gap portion54is configured between the annular portion52and the top plate51in the radial direction.

The projected portion53extends downward from the outer edge of the top plate51. Specifically, the projected portion53extends downward from a lower end of a side wall portion of the top plate51configuring the lower recess portion51b. The projected portion53has a rectangular shape as viewed in the radial direction. The projected portion53has a thickness in the radial direction and an outer surface of the projected portion53in the radial direction is flush with an outer surface of the annular portion52. In other words, the projected portion53has a shape extending downward from the top plate51and the annular portion52. The projected portion53has a hollow portion532that is recessed toward the outside in the radial direction. The hollow portion532communicates with the gap portion54between the top plate51and the annular portion52in the radial direction, and the inside of the cylindrical portion41. The second housing50has a plurality of the projected portions53. The plurality of the projected portions53are disposed at intervals in the circumferential direction. In the embodiment, the plurality of the projected portions53are disposed at equal intervals in the circumferential direction.

A cylindrical hub portion55extending in the axial direction is provided at the center portion on the lower surface of the top plate51. The hub portion55surrounds the shaft hole51c. The hub portion55has a cylindrical shape. The hub portion55is disposed in the lower recess portion51bas viewed in the axial direction. When the second housing50is disposed on the first housing40, the hub portion55surrounds the upper bearing holding portion42a(seeFIG. 3).

A plurality of first ribs56extending from both end portions of the projected portion53in the circumferential direction to the inside in the radial direction as viewed in the axial direction are disposed on the lower surface of the top plate51. The plurality of the first ribs56are disposed in the circumferential direction. The first ribs56are disposed in the lower recess portion51bas viewed in the axial direction. The first rib56protrudes downward from the lower surface of the top plate51. The first rib56extends from an inner surface of a side wall configuring the lower recess portion51bto an outer surface of the hub portion55.

An end portion of the projected portion53in the circumferential direction indicates a region having a width in the circumferential direction. In the embodiment, the first rib56is configured of two ribs disposed at intervals in the circumferential direction, but the number of the ribs configuring the first rib56may be one or three or more. In the embodiment, the first rib56with respect to each of the projected portions53is provided on the lower surface of the top plate51and the number of the first ribs56is six that are the same as that of the projected portions53. However, a configuration in which the first ribs56are not provided with respect to all the projected portions53may be provided.

According to the embodiment, it is possible to improve the rigidity of the second housing50by the first ribs56. Since the first rib56is provided with respect to each of the projected portions53, it is possible to improve the rigidity around each of the projected portions53. It is possible to suppress vibration of the second housing50due to the improvement of the rigidity when driving the motor1.

An annular second rib57is disposed on the lower surface of the top plate51. The second rib57is disposed in the lower recess portion51bas viewed in the axial direction. The second rib57protrudes downward from the lower surface of the top plate51. The second rib57is positioned on the inside from the outer end of the first rib56in the radial direction. The second rib57connects the plurality of the first ribs56. In the embodiment, the second rib57is disposed on the outside of the hub portion55in the radial direction and has an annular shape. It is possible to further improve the rigidity of the second housing50by the second rib57compared to a case where only the first ribs56are provided. Therefore, it is possible to further suppress the vibration of the second housing50when driving the motor1. Moreover, in the embodiment, the number of the second ribs57is one, but a plurality of the second ribs57may be provided.

The top plate51has a plurality of through-holes58penetrating in the axial direction. The second housing50is fixed to the first housing40by the fixing member2inserted into the through-hole58. Therefore, the second housing50can be firmly fixed to the first housing40by the fixing member2. That is, it is possible to suppress the vibration of the second housing50caused by the driving of the motor1.

As described above, in the embodiment, the fixing member2is the screw. The screw hole42bfor fixing the screw2is provided in the upper lid portion42. The plurality of the through-holes58are disposed in the upper recess portion51aas viewed from above in the axial direction. The number of the plurality of the through-holes58is three, but the number may be changed. The number of fixing portions is increased by increasing the number of the through-holes58, so that the second housing50can be firmly fixed to the first housing40. A screw recess portion59, which overlaps the through-hole58as viewed in the axial direction and of which a diameter is larger than that of the through-hole58, is provided on the upper surface of the top plate51. A head portion of the screw2can be prevented from protruding from the upper surface of the top plate51by the screw recess portion59.

The through-hole58penetrates a part of the first rib56. In other words, at least a part of an inner peripheral surface of the through-hole58is configured of a part of the first rib56. According to the configuration, the through-hole58for inserting the fixing member2is provided in the vicinity of a portion of which the rigidity is enhanced by providing the first rib56. Therefore, it is possible to firmly fixing and to suppress the vibration of the second housing50by the fixing member2. However, the through-hole58may be provided at a position away from the first rib56.

The through-hole58penetrates a part of the second rib57. In other words, at least a part of the inner peripheral surface of the through-hole58is configured of a part of the second rib57. According to the embodiment, the through-hole58for inserting the fixing member2is provided in the vicinity of the portion of which the rigidity is enhanced by providing the second rib57. Therefore, it is possible to firmly fixing and to suppress the vibration of the second housing50by the fixing member2. However, the through-hole58may be provided at a position away from the second rib57. In the embodiment, the through-hole58is configured to penetrate a part of the first rib56and a part of the second rib57, and it is possible to firmly perform the fixing by the fixing member2.

The plurality of the through-holes58are disposed at equal intervals in the circumferential direction. Therefore, when the second housing50is fixed to the first housing40, it is possible to prevent uneven distribution of portions having high fixing strength and to suppress occurrence of vibration.

FIG. 5is an enlarged view of a periphery of the projected portion53of the second housing50. As illustrated inFIGS. 4 and 5, the projected portion53has a first groove53aextending in the circumferential direction at a lower end portion. The first groove53ais recessed upward from the lower end portion of the projected portion53in the axial direction. The first groove53aextends from one end to the other end of the projected portion53in the circumferential direction. The first groove53afits with a part of the cylindrical portion41.

The projected portion53is inserted into the recess portion41a(seeFIG. 2) of the cylindrical portion41. That is, the number of the plurality of the recess portions41ais the same as that of the plurality of the projected portions53.FIG. 6is a vertical sectional view schematically illustrating a relationship between the projected portion53and the recess portion41a. As illustrated inFIG. 6, the projected portion53is inserted into the recess portion41a, so that a bottom wall portion411of the recess portion41afits into the first groove53a. In other words, the projected portion53is inserted into the recess portion41a, so that a lower end of the projected portion53is positioned on a lower side from the bottom wall portion411. Therefore, a part of the cylindrical portion41fits into the first groove53aof the projected portion53, so that the projected portion53can be fixed to the first housing40. Therefore, it is possible to suppress that the vibration occurs in the projected portion53.

As illustrated inFIGS. 5 and 6, the first groove53ahas a first groove inside protrusion53bprotruding in the radial direction on the side surface. In the embodiment, a plurality of the first groove inside protrusions53bare provided. Specifically, the first groove inside protrusion53bis provided on each of two side surfaces531aand531bwhich configure the first groove53aand face each other in the radial direction. The first groove inside protrusion53bprovided on the side surface531aon the inside in the radial direction protrudes to the outside in the radial direction. The first groove inside protrusion53bprovided on the side surface531bon the outside in the radial direction protrudes to the inside in the radial direction. The number of the first groove inside protrusions53bprovided on each of the side surfaces531aand531bis the same, and in the embodiment, three protrusions are provided. In each of the side surfaces531aand531b, the plurality of the first groove inside protrusions53bare aligned at intervals in the circumferential direction. Three first groove inside protrusions53bprovided on the side surface531aon the inside in the radial direction and three first groove inside protrusions53bprovided on the side surface531bon the outside in the radial direction face each other in the radial direction.

The projected portion53is inserted into the recess portion41a, so that the first groove inside protrusion53bprovided on the side surface531aon the inside in the radial direction is in contact with an inner surface of the cylindrical portion41in the radial direction. The projected portion53is inserted into the recess portion41a, so that the first groove inside protrusion53bprovided on the side surface531bon the outside in the radial direction is in contact with an outer surface of the cylindrical portion41in the radial direction.

The first groove inside protrusion53bis provided, so that it is possible to suppress a decrease in the strength of the lower end of the projected portion53at which the first groove53ais provided and to firmly fix the projected portion53to the cylindrical portion41. Moreover, the number of the first groove inside protrusions53bmay be changed. For example, the first groove inside protrusion53bmay be provided on only one of the side surface531aon the inside in the radial direction and the side surface531bon the outside in the radial direction. In addition, the number of the first groove inside protrusions53baligned in the circumferential direction may be one or more on the side surface531aon the inside in the radial direction or the side surface531bon the outside in the radial direction. In addition, in a case where the first groove inside protrusions53bare provided on both the side surface531aon the inside in the radial direction and the side surface531bon the outside in the radial direction, the position of the first groove inside protrusion53bmay be shifted or the number may be different between the side surface531aon the inside in the radial direction and the side surface531bon the outside in the radial direction. The first groove inside protrusion53bmay not be provided. In this case, the side surface configuring the first groove53amay be configured to be in contact with the cylindrical portion41.

FIG. 7is a view for explaining a first modification example of the projected portion53.FIG. 7is a plan view of a projected portion53A as viewed from below. In addition to the projected portion53A, a cylindrical portion41is indicated by a one-dotted chain line inFIG. 7.

As illustrated inFIG. 7, the projected portion53A may have a second groove53cextending in the axial direction on the side surface portion. The second groove53cis recessed in the circumferential direction from the side surface portion of the projected portion53A. The second groove53cmay extend from a lower end to an upper end of the projected portion53A, or may not extend to the upper end. A length of the second groove53cin the axial direction may be appropriately determined within a range in which the projected portion53A can be inserted into a predetermined position of the recess portion41a. Moreover, the upper end of the projected portion53A described in here is a base of the projected portion53A.

In the modification example, the second grooves53care provided at both side surface portions of the projected portion53A in the circumferential direction. However, the second groove53cmay be provided at only one side surface portion of the projected portion53A in the circumferential direction. In addition, a first groove53amay be provided at the projected portion53A at which the second groove53cis provided.

The projected portion53A is inserted into the recess portion41a, so that a side wall portion412of the recess portion41afits into the second groove53c. In other words, the projected portion53A is inserted into the recess portion41a, so that an end portion of the projected portion53A in the circumferential direction is positioned on the outside from the side wall portion412in the circumferential direction. Therefore, since a part of the cylindrical portion41fits into the second groove53cof the projected portion53A, it is possible to fix the projected portion53A to the first housing40. Therefore, it is possible to suppress that vibration occurs in the projected portion53A.

As illustrated inFIG. 7, it is preferable that the second groove53chas a second groove inside protrusion53dprotruding in the radial direction on the side surface. It is preferable that a plurality of the second groove inside protrusions53dare provided. Similar to the first groove inside protrusions53b, it is preferable that the second groove inside protrusions53dare provided on both two side surfaces which configure the second groove53cand face each other in the radial direction. In addition, it is preferable that a plurality of the second grooves53care provided at intervals in the axial direction on each side surface. The projected portion53A is inserted into the recess portion41a, so that the second groove inside protrusion53dis in contact with the cylindrical portion41. The second groove inside protrusion53dis provided, so that it is possible to suppress a decrease in the strength of the end portion of the projected portion53A in the circumferential direction at which the second groove53cis provided and to firmly fix the projected portion53A to the cylindrical portion41. Moreover, the second groove inside protrusion53dmay not be provided. In this case, the side surface configuring the second groove53cmay be configured to be in contact with the cylindrical portion41.

FIG. 8is a view for explaining a second modification example of the projected portion53. As illustrated inFIG. 8, a projected portion53B has a tapered shape in which a width in the circumferential direction decreases from an upper side to a lower side. In the configuration, for example, the width of a lower end portion of the projected portion53B in the circumferential direction is equal to a width of a recess portion41ain the circumferential direction. Specifically, the width of the lower end portion of the projected portion53B in the circumferential direction is slightly smaller than the width of the recess portion41ain the circumferential direction. The projected portion53B has a portion in which the width in the circumferential direction is larger than the width of the recess portion41aon the upper side from the lower end portion due to the tapered shape. Therefore, the projected portion53B inserted into the recess portion41ais press-fitted into the recess portion41a.

According to the modification example, it is possible to firmly fix the projected portion53B to the cylindrical portion41without providing a first groove53aand a second groove53cin the projected portion53B. However, also in the case of the modification example, at least one of the first groove53aand the second groove53cmay be provided in the projected portion53B.

Next, an embodiment of the blowing device100to which the motor1of the embodiment is applied will be described.FIG. 9is a sectional perspective view of the blowing device100according to the embodiment of the disclosure.FIG. 10is an exploded perspective view of the blowing device100according to the embodiment of the disclosure. As illustrated inFIGS. 9 and 10, the blowing device100includes the motor1and the impeller110. The blowing device100further includes an impeller cover120. The motor1is the motor of the embodiment described above.

The impeller110is disposed above the second housing50. The impeller110is fixed to the shaft10and is capable of rotating together with the shaft10. Specifically, the impeller110includes an impeller body111and an impeller hub112.

The impeller body111includes a base portion1111, a plurality of blades1112, and a shroud1113. The base portion1111has a disk shape. The base portion1111has a base portion through-hole1111aat a center portion. The blade1112is a plate-like member curved in the circumferential direction extending from the inside to the outside in the radial direction on the upper side of the base portion1111. The blades1112are disposed to stand upright along the axial direction. The shroud1113has a cylindrical shape tapered toward the upper side in the axial direction. An opening portion at the center of the shroud1113becomes an impeller suction port110aof the impeller110. The base portion1111and the shroud1113are connected by the plurality of the blades1112.

The impeller hub112includes an impeller cylindrical portion1121and an impeller flange portion1122. The impeller cylindrical portion1121extends in the axial direction and has a cylindrical shape. The impeller flange portion1122expands from an outer peripheral surface of the impeller cylindrical portion1121to the outside in the radial direction. The impeller flange portion1122has an annular shape.

The impeller cylindrical portion1121is inserted into the base portion through-hole1111a, so that the impeller hub112is attached to the impeller body111. The impeller cylindrical portion1121may be press-fitted into the base portion through-hole1111a, or may be fixed by adhesive or the like. The upper end portion of the shaft10is fitted into the impeller cylindrical portion1121, so that the impeller110is fixed to the shaft10. The impeller flange portion1122is in contact with an upper surface of the base portion1111and functions as a stopper.

The impeller cover120is disposed above the impeller110to cover the impeller110. The impeller cover120has a cylindrical shape tapered toward the upper side in the axial direction. The impeller cover120has the cover suction port121on the upper side. The impeller cover120has a cover protrusion122on the outer peripheral surface in the radial direction. The cover protrusion122extends in the axial direction and protrudes downward from a lower end of the impeller cover120. The cover protrusion122has a protrusion through-hole122apenetrating in the radial direction. The protrusion through-hole122ahas a rectangular shape as viewed in the radial direction. In the embodiment, the impeller cover120has three cover protrusions122. The three cover protrusions122are disposed at equal intervals in the circumferential direction. The number and the arrangement of the cover protrusions122may be changed.

The second housing50has a housing protrusion50aextending to the outside in the radial direction on the outer peripheral surface in the radial direction. The housing protrusion50ahas a rectangular shape as viewed in the radial direction. In the embodiment, the number of the housing protrusions50ais three in accordance with the number of the cover protrusions122. The housing protrusion50ais inserted into the protrusion through-hole122aof the cover protrusion122, so that the impeller cover120is fixed to the second housing50. Moreover, the fixing method of the impeller cover120to the second housing50may be another method. For example, a fixing member such as a screw may be used or adhesive may be used.

When the impeller110is rotated by the driving of the motor1, the fluid is sucked from the cover suction port121into the blowing device100. Thick arrows ofFIG. 9indicate a flow of the fluid when driving the motor1. Moreover, a representative example of the fluid is air.

The fluid sucked from the cover suction port121is sucked into the impeller110via the impeller suction port110a. The impeller110discharges the fluid sucked from the impeller suction port110ato the outside in the radial direction via an internal flow path. The fluid discharged from the impeller110enters the gap portion54of the second housing50. A part of the fluid entering the gap portion54is discharged to the outside via an opening formed between the projected portions53adjacent in the circumferential direction of the second housing50.

As described above, the hollow portion532of the projected portion53communicates with the gap portion54. Furthermore, since the projected portion53has a structure to be inserted into the recess portion41aof the cylindrical portion41, the hollow portion532communicates with the inside of the cylindrical portion41. Therefore, out of the fluid entering the gap portion54, the fluid discharged to the outside enters the inside of the cylindrical portion41through the hollow portion532. That is, the projected portion53can guide the fluid discharged from the impeller110to the inside of the first housing40. Therefore, the inside of the motor1can be cooled. The fluid guided to the inside of the cylindrical portion41is discharged to the outside of the first housing40via the lower lid through-hole62. The circuit board80can be cooled by the fluid discharged from the lower lid through-hole62.

According to the embodiment, the rigidity of the second housing50is improved by the first ribs56and the second rib57. In addition, the second housing50is fixed to the first housing40by the fixing member2and is fixed to the first housing using the first groove53aprovided in the projected portion53. That is, the second housing50is firmly fixed to the first housing40. Particularly, the projected portion53is firmly fixed to the first housing40. Therefore, in a case where the impeller110rotates, the vibration of the second housing50can be suppressed and occurrence of noise can be suppressed.

Next, an embodiment of the cleaner200to which the blowing device100of the embodiment is applied will be described.FIG. 11is a perspective view of the cleaner200according to the embodiment of the disclosure. As illustrated inFIG. 11, the cleaner200has the blowing device100. The cleaner200is a so-called stick type electric cleaner. Moreover, the cleaner including the blowing device100may be another type electric cleaner such as a so-called robot type, canister type, or handy type.

The cleaner200has a casing201in which an intake portion202and an exhaust portion203are respectively provided on a lower surface and an upper surface. The cleaner200has a rechargeable battery (not illustrated) and is operated by electric power supplied from the battery. However, the cleaner200may have a power supply cord and operate with electric power supplied via the power supply cord connected to a power supply outlet provided on a wall surface of a living room.

An air passage (not illustrated) for connecting the intake portion202and the exhaust portion203is formed in the casing201. A dust collecting portion (not illustrated), a filter (not illustrated), and the blowing device100are disposed in order from the intake portion202(upstream) to the exhaust portion203downstream) in the air passage. Trash such as dust contained in the air circulating through the air passage is captured by the filter and is collected in the dust collecting portion formed in a container shape. The dust collecting portion and the filter are configured to be attachable and detachable to and from the casing201.

A grip portion204and an operation portion205are provided on an upper portion of the casing201. A user can grasp the grip portion204and move the cleaner200. The operation portion205has a plurality of buttons205a. The user performs operation setting of the cleaner200with the operation of the buttons205a. For example, a driving start, a driving stop, and a change in a rotational speed of the blowing device100, and the like are instructed by operations of the buttons205a. A rod-like suction pipe206is connected to the intake portion202. A suction nozzle207is detachably attached to the suction pipe206at an upstream end of the suction pipe206. Moreover, the upstream end of the suction pipe206is a lower end of the suction pipe206inFIG. 11.

The cleaner200of the embodiment has the blowing device100capable of suppressing vibration and noise in the second housing50. Therefore, also in the cleaner200, vibration and noise can be suppressed.

Various modifications can be made to the various technical features disclosed in the present specification without departing from the gist of the technical creation thereof. Also, a plurality of the embodiments and modification examples described in this specification may be implemented in combination in a possible range.

The present disclosure may be utilized, for example, in an electric machine having a blowing device such as a cleaner.