JPWO2017179498A1 - Blower and vacuum cleaner - Google Patents

Abstract

An impeller rotatable around a central axis extending in the vertical direction; a motor that is positioned below the impeller and that rotates the impeller; an airflow passage in the internal space; and a suction port that allows fluid to flow into the internal space; A blower having a blowout port for discharging fluid from the internal space and accommodating the impeller, wherein the impeller includes a plurality of blades arranged in a circumferential direction, and the plurality of blades An annular shroud that has an opening at a position facing the suction port in the axial direction and a base plate that connects the lower portions of the plurality of blades and extends in the radial direction. A cover portion covering at least a part of the blade and the shroud, and an inner diameter of the shroud is equal to or larger than an outer diameter of the base plate Ku, wherein the cover portion includes a first convex portion that is disposed radially inward of the inner circumferential surface of the projecting from the lower surface of the cover portion axially downwardly shroud. [Selection] Figure 7

Description

  The present invention relates to a blower and a vacuum cleaner.

  A conventional blower is disclosed in Japanese Laid-Open Patent Publication No. 2002-156128. The turbofan disclosed in Japanese Patent Laid-Open Publication No. 2002-156128 includes a casing, a motor, a base plate, a blade, and a shroud. The base plate, the blade, and the shroud are accommodated in the casing. A plurality of blades are arranged in the circumferential direction. The shroud connects the ends of a plurality of blades. The plurality of blades are arranged on the periphery of the base plate.

  The casing has a suction side end portion, a straight portion, and an inclined step portion. The inner diameter of the suction side end is the same as or larger than the outer diameter of the base plate.

  Air is discharged from the central portion of the turbofan in the outer circumferential direction. And since the shroud has the above characteristics, it is claimed that the noise of the turbofan is reduced.

Japanese publication: JP 2002-156128 A

  However, according to the turbofan disclosed in Japanese Patent Laid-Open Publication No. 2002-156128, a part of the air discharged to the radially outer side of the blade flows backward from the gap between the shroud and the casing to the radially inner side. . At this time, turbulent flow is generated in the airflow passage inside the casing, or air resistance is generated due to the airflow that has flowed backward, and there is a problem in that the blowing efficiency of the blower decreases.

  Then, an object of this invention is to provide the air blower which can suppress that a turbulent flow generate | occur | produces in the airflow path of a duct, or a backflow of airflow to radial inside, and can improve ventilation efficiency. Moreover, an object of this invention is to provide the cleaner provided with the air blower which can improve ventilation efficiency.

  An air blower according to an exemplary embodiment of the present invention includes an impeller that can rotate around a central axis that extends in the vertical direction, and a motor unit that is positioned below the impeller and that rotates the impeller around the central axis. A blower device comprising: an airflow passage in the internal space; a suction port for allowing fluid to flow into the internal space; and a duct for receiving the fluid from the internal space and accommodating the impeller. The impeller includes a plurality of blades arranged in a circumferential direction, an annular shroud that connects upper portions of the plurality of blades and has an opening at a position facing the suction port in the axial direction, and the plurality of blades A base plate that extends in a radial direction, and the duct has a cover portion that covers at least a part of the blade and the shroud, The inner diameter of the shroud is the same as or larger than the outer diameter of the base plate, and the cover portion protrudes axially downward from the lower surface of the cover portion and is arranged on the radially inner side of the inner peripheral surface of the shroud. It has a convex part.

  According to an exemplary embodiment of the present invention, it is possible to provide a blower capable of improving the blowing efficiency. Moreover, according to exemplary embodiment of this invention, a vacuum cleaner provided with such an air blower can be provided.

FIG. 1 is a cross-sectional view of a cleaning robot according to an embodiment of the present invention. FIG. 2 is a perspective view of the air blower according to the embodiment of the present invention. FIG. 3 is a longitudinal sectional view of the air blower according to the embodiment of the present invention. FIG. 4 is a perspective view of the impeller according to the embodiment of the present invention as viewed from above. FIG. 5 is a top view of the impeller according to the embodiment of the present invention. FIG. 6 is a side cross-sectional view of the impeller according to the embodiment of the present invention. FIG. 7 is an enlarged longitudinal sectional view showing a part of the blower according to the embodiment of the present invention. FIG. 8 is an enlarged longitudinal sectional view showing a part of the blower according to the embodiment of the present invention. FIG. 9 is an enlarged longitudinal sectional view showing a part of a blower of a modification according to the embodiment of the present invention. FIG. 10 is an enlarged longitudinal sectional view showing the vicinity of the shroud of the air blower according to the modification of the embodiment of the present invention. FIG. 11 is an enlarged longitudinal sectional view showing the vicinity of the shroud of the air blower of the modification according to the embodiment of the present invention.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the direction in which the central axis A of the blower 1 shown in FIG. 3 extends is simply referred to as “axial direction”, and the radial direction and the circumferential direction around the central axis A of the blower 1 are simply “ It is called “radial direction” and “circumferential direction”. Similarly, for the impeller 20 shown in FIG. 4 to FIG. 6, the directions that coincide with the axial direction, the radial direction, and the circumferential direction of the blower device 1 in the state of being incorporated in the blower device 1 are simply “axial direction”, “ It is called “radial direction” and “circumferential direction”. The vertical direction is simply a name used for explanation, and does not limit the actual positional relationship or direction.

<1. Configuration of vacuum cleaner>
An air blower according to an exemplary embodiment of the present invention will be described. FIG. 1 is a cross-sectional view of a cleaning robot 100 according to an exemplary embodiment of the present invention. As shown in FIG. 1, the blower 1 is mounted on a cleaning robot (vacuum cleaner) 100 and serves as suction means. used.

  The cleaning robot 100 cleans the floor F by sucking air containing dust on the floor F and exhausting the air from which dust has been removed while running on the floor F at the place where it is installed. The cleaning robot 100 includes a suction path 104, a dust collection container 105, a filter unit 106, an exhaust path 107, and the blower 1 inside a disk-shaped casing 101. Drive wheels 109 and front wheels 110 are provided on the lower surface of the housing 101.

  The housing 101 has an intake port 103 at the center of the lower surface and an exhaust port 108 at the side surface. By driving the blower 1, the cleaning robot 100 sucks in air containing dust on the floor F from the air inlet 103 while self-propelled. Air containing dust sucked into the housing 101 from the air inlet 103 passes through the suction passage 104 and flows into the dust collecting container 105. The airflow that has flowed into the dust collection container 105 passes through the filter unit 106, passes through the exhaust passage 107, and is sucked into the blower 1. The air sucked into the blower 1 is exhausted from the exhaust port 108 obliquely upward to the rear. At this time, dust contained in the airflow in the dust collection container 105 is captured by the filter unit 106, and dust D accumulates in the dust collection container 105.

<2. Configuration of blower>
FIG. 2 is a perspective view of the blower 1 according to the embodiment of the present invention. FIG. 3 is a vertical cross-sectional view of the blower device 1 according to the embodiment of the present invention. As shown in FIGS. 2 and 3, the blower 1 includes an impeller 20, a motor unit 30, and a duct 10. The impeller 20 is accommodated in the internal space of the duct 10. The motor unit 30 is positioned below the impeller 20 and rotates the impeller 20 around the central axis A.

  The impeller 20 is connected to a shaft (not shown) extending in the axial direction from the motor unit 30 and is supported rotatably about the central axis A. That is, the impeller 20 can rotate around the central axis A extending in the vertical direction. The control board 40 is disposed on the lower side in the axial direction of the motor unit 30 and controls the motor unit 30.

<3. Duct configuration>
The duct 10 has an airflow passage 13 in the internal space, a suction port 11 for flowing fluid into the internal space, and an air outlet 12 for discharging fluid from the internal space, and accommodates the impeller 20. The duct 10 is constituted by a cover part 14, a peripheral wall part 15, and a motor housing 16, and an airflow passage 13 is formed in an internal space surrounded by these. More specifically, the duct 10 has a cover portion 14 that covers at least a part of the blade 23 and the shroud 22. The cover portion 14 covers the upper side of the impeller 20 and is formed in an annular shape in plan view from the axial direction. The outer diameter of the cover portion 14 is larger than the outer diameter of the impeller 20. In the present embodiment, the duct 10 is constituted by a member including a part of the cover part 14 and the peripheral wall part 15, and a member including a part of the peripheral wall part 15 and the motor housing 16. Thereby, since said 2 member can be shape | molded as a separate resin member, the duct 10 can be comprised cheaply.

  A cylindrical cylindrical portion 14 a extending upward in the axial direction is provided at the center of the cover portion 14. A circular suction port 11 is formed in the cylindrical portion 14a in a plan view from the axial direction. The suction port 11 is disposed so as to face an opening 22a of the shroud 22 described later in the axial direction, and gas (fluid) flows from the outside into the internal space of the duct 10 through the suction port 11.

  The peripheral wall 15 covers the impeller 20 from the side, extends from the outer peripheral edge of the cover 14 downward in the axial direction, and is formed in a cylindrical shape. Further, the peripheral wall portion 15 is provided with a nozzle 15a extending outward in the radial direction, and the nozzle 15a is formed with an outlet 12 for discharging gas (fluid) from the internal space of the duct 10.

  The motor housing 16 is located on the lower side of the impeller 20 in the axial direction. More specifically, the blower 1 further includes a motor housing 16 positioned below the base plate 21 described later. The upper surface of the motor housing 16 extends in the radial direction and extends to the lower end of the peripheral wall portion 15 for connection. The peripheral surface of the motor housing 16 is formed in a cylindrical shape extending from the outer peripheral edge of the peripheral wall portion 15 to the lower side in the axial direction, and the motor portion 30 and the control board 40 are accommodated inside the motor housing 16.

  On the upper surface of the motor housing 16, an annular recess 16 a that is recessed downward on the radially outer side from the impeller 20 is formed. An airflow passage 13 including an annular region on the radially outer side of the impeller 20 is formed between the suction port 11 and the outlet 12 by the peripheral wall portion 15, the recess portion 16 a, and the cover portion 14.

<4. Impeller configuration>
FIG. 4 is a perspective view of the impeller 20 according to the embodiment of the present invention as viewed from above, and FIG. 5 is a top view of the impeller 20 according to the embodiment of the present invention. FIG. 6 is a side sectional view of the impeller 20 according to the embodiment of the present invention.

  As shown in FIGS. 4 to 6, the impeller 20 includes a plurality of blades 23, an annular shroud 22, and a base plate 21. The blade 23 is interposed between the base plate 21 and the shroud 22. The plurality of blades 23 are arranged in the circumferential direction.

  The shroud 22 has an annular shape having an opening 22a at a position that connects the upper portions of the plurality of blades 23 and faces the suction port 11 in the axial direction. More specifically, the shroud 22 is formed in an annular shape by connecting the upper portions of the plurality of blades 23, and an opening 22a for taking in gas is formed in the center. The opening 22a is circular in plan view from the axial direction.

  The base plate 21 connects the lower portions of the plurality of blades 23 and spreads in the radial direction. The base plate 21 is formed in a disc shape. The base plate 21 has a base plate protrusion 21 a that protrudes downward from the lower surface of the base plate 21. More specifically, the base plate protruding portion 21a protrudes from the radially outer edge of the lower surface of the base plate 21 and is formed in an annular shape (see FIG. 6).

  The blade 23 has a first blade 23a and a second blade 23b having different lengths in the radial direction, and the first blade 23a and the second blade 23b are alternately arranged in the circumferential direction. The first blade 23a and the second blade 23b are plate-like members that stand in the axial direction and extend from the radially inner side to the outer side. The radially inner end of the first blade 23a is positioned radially inward of the radially inner end of the second blade 23b, and the first blade 23a is longer in the radial direction than the second blade 23b.

  Further, the first blade 23a and the second blade 23b have a radially outer end that is rearward in the rotational direction with respect to the radially inner end when the impeller 20 is rotated counterclockwise in a plan view from the upper side in the axial direction. It inclines to the side, and is curving so that the rotation direction back may become concave (refer FIG. 5). Further, the distance between the first blade 23a and the second blade 23b increases toward the outside in the radial direction.

  The radially outer ends 24a and 24b of the first blade 23a and the second blade 23b extend radially outward from the outer peripheral edge of the base plate 21 (see FIG. 4). That is, the radially outer ends 24 a and 24 b of the blade 23 extend radially outward from the outer peripheral edge of the base plate 21. The radially inner ends of the first blade 23a and the second blade 23b extend radially inward from the suction port 11 (see FIG. 3). In other words, the radially inner end of the blade 23 extends radially inward from the suction port 11. Thereby, the blade 23 can be formed large in the radial direction, and the air volume generated by the rotation of the impeller 20 can be increased. The outer peripheral edge of the base plate 21 may have another shape. For example, a part of the outer peripheral edge may be cut out radially inward from the circumferential outer edge.

  The upper ends of the first blade 23a and the second blade 23b have protrusions 25a and 25b that protrude upward in the axial direction (see FIG. 6). The protrusions 25 a and 25 b are located on the radially inner side of the opening 22 a and are arranged on the same circle, and protrude upward from the upper end of the shroud 22.

  Further, the upper ends of the first blade 23a and the second blade 23b are inclined surfaces 26a, 26b descending radially inward from the projecting portions 25a, 25b and slopes descending radially outward from the projecting portions 25a, 25b. It has surfaces 27a and 27b.

  In addition, the inclined surfaces 27 a and 27 b are formed with protrusions 28 a and 28 b that protrude axially upward on the radially outer side than the opening 22 a of the shroud 22, and the upper ends of the protrusions 28 a and 28 b extend to the lower surface of the shroud 22. Connected to the shroud 22. In other words, the blade 23 has protrusions 28a and 28b that protrude in the axially upper side on the radially outer side than the first convex portion 17 (see FIG. 7) described later. Accordingly, the blade 23 can be formed larger in the axial direction outside the opening 22a in the radial direction, and the amount of air generated by the rotation of the impeller 20 can be increased.

  The base plate 21, the shroud 22, and the blade 23 are formed of a resin molded product of the same material, and the inner diameter D2 of the shroud 22 is formed to be the same size as the outer diameter D1 of the base plate 21 (see FIG. 6).

  Thereby, when the impeller 20 straddling the base plate 21 and the shroud 22 is formed, the upper and lower molds can be prevented from interfering with each other and the molds can be pulled out on the upper and lower sides in the axial direction. Therefore, the impeller 20 can be integrally formed with a mold, and the mass productivity of the impeller 20 can be improved. Even when the inner diameter D2 of the shroud 22 is formed larger than the outer diameter D1 of the base plate 21, the impeller 20 can be integrally formed by a mold.

<5. Relationship between duct and impeller>
7 and 8 are enlarged longitudinal sectional views showing a part of the blower 1 according to the embodiment of the present invention, and show the relationship between the duct 10 and the impeller 20. As shown in FIG. 7, the shroud 22 has an inner peripheral surface 22b that constitutes an opening 22a. The cover part 14 has a first convex part 17 that protrudes downward in the axial direction from the lower surface of the cover part 14 and is arranged radially inward from the inner peripheral surface 22 b of the shroud 22. The outer peripheral surface of the first convex portion 17 faces the inner peripheral surface 22b of the shroud 22 in the radial direction. In addition, the outer peripheral surface of the 1st convex part 17 and the inner peripheral surface 22b of the shroud 22 do not necessarily need to oppose on the peripheral surface. That is, it is only necessary that the outer surface of the first convex portion 17 is opposed to the inner surface 22b of the shroud 22 in the radial direction. In addition, the outer surface of the 1st convex part 17 described here and the shape of the inner surface 22b of the shroud 22 mean that it is not restricted to a surrounding surface. For example, the outer surface of the first convex portion 17 and the inner surface 22b of the shroud 22 may have irregularities formed on a part of the peripheral surface.

  The first convex portion 17 blocks the flow path of the air R <b> 1 that flows backward inward in the radial direction from the gap between the shroud 22 and the cover portion 14. For this reason, it is possible to suppress a part of the air blown outward in the radial direction of the impeller 20 from flowing back through the gap between the shroud 22 and the cover portion 14. Therefore, it is possible to prevent the blowing efficiency from being lowered due to the occurrence of turbulent flow in the airflow passage 13 or air resistance due to the air flowing backward. The radial gap between the outer peripheral surface of the first convex portion 17 and the inner peripheral surface 22 b of the shroud 22 is narrower than the axial gap between the shroud 22 and the cover portion 14. Therefore, it is possible to block the flow of the air R1 that flows backward inward in the radial direction from the gap between the shroud 22 and the cover portion 14.

  In addition, the lower end of the radially outer end of the first protrusion 17 extends to a position where the axial height is substantially the same as the lower end of the inner peripheral surface 22 b of the shroud 22 or is axially lower. Thereby, the air flowing toward the radially outer side along the lower surface of the cover portion 14 is smoothly guided from the lower end of the first convex portion 17 to the lower end of the inner peripheral surface 22b of the shroud 22, and the lower surface of the shroud 22 is It passes through and is blown outward in the radial direction of the impeller 20. Therefore, the blowing efficiency of the blower 1 can be further improved. That is, since the circulated air is reduced from hitting the inner peripheral surface 22b of the shroud 22, it can be efficiently blown out radially outward.

  As shown in FIG. 8, the protrusions 28 a and 28 b (not shown in FIG. 7, see FIG. 4) of the first blade 23 a and the second blade 23 b are shroud 22 on the radially outer side than the first protrusion 17. The first convex portion 17 is opposed to the inclined surfaces 27a and 27b in the vertical direction. For this reason, the first blade 23a and the second blade 23b are located on the radially outer side of the first convex portion 17 as the blade first region L1, and the region facing the first convex portion 17 in the vertical direction is the blade first region. In the case of the two regions L2, the upper ends of the first blade 23a and the second blade 23b are positioned above the upper end of the radially outer end of the blade second region L2 in the blade first region L1.

  That is, the blade 23 includes a blade first region L1 positioned radially outward from the first convex portion 17 and a blade second region L2 facing the first convex portion 17 in the vertical direction. The upper end of the first region L1 is located above the upper end of the radially outer end of the blade second region L2. Therefore, even when the impeller 20 vibrates in the vertical direction during rotation, the first blade 23a and the second blade 23b can be prevented from coming into contact with the first convex portion 17.

  Returning to FIG. 7, the upper surface of the motor housing 16 is provided with an annular groove 16 b that axially opposes the base plate protrusion 21 a that protrudes from the outer peripheral end of the lower surface of the base plate 21. The width of the groove 16b in the radial direction is larger than that of the base plate protrusion 21a. Thereby, the axial gap between the lower surface of the base plate 21 and the upper surface of the motor housing 16 can be narrowed by disposing the base plate protruding portion 21 a close to the groove portion 16 b.

  As a result, it is possible to prevent a part of the air blown outward in the radial direction of the impeller 20 from flowing back through the gap between the lower surface of the base plate 21 and the upper surface of the motor housing 16, and the turbulent flow in the airflow passage 13. It can prevent that ventilation efficiency falls by the air resistance by the air which generate | occur | produces or flows backward.

  Further, the axial gap between the lower end of the base plate protrusion 21 a and the upper surface of the motor housing 16 is narrower than the axial gap between the lower surface of the base plate 21 and the upper surface of the motor housing 16. Therefore, a part of the air blown to the outer side in the radial direction of the impeller 20 can be further suppressed from flowing into the gap between the lower surface of the base plate 21 and the upper surface of the motor housing 16 and flowing backward in the radial direction.

  The base plate protruding portion 21 a may be formed at a place other than the radially outer edge of the base plate 21. For example, on the lower surface of the base plate 21, the base plate protrusion 21 a may be formed at a position inside the radial outer edge. Even in this case, a part of the air blown outward in the radial direction of the impeller 20 is prevented from flowing into the gap between the lower surface of the base plate 21 and the upper surface of the motor housing 16 as the air R2 and flowing backward in the radial direction. be able to.

<6. Driving the blower>
When the motor unit 30 is driven, the impeller 20 rotates about the central axis A. Thereby, air is taken into the duct 10 from the suction port 11. The air taken into the duct 10 is accelerated radially outward by the impeller 20. The air accelerated radially outward passes between the shroud 22 and the base plate 21 and is blown out radially outward of the impeller 20. The air blown to the outer side in the radial direction of the impeller 20 passes through the air flow passage 13 formed in the circumferential direction inside the duct 10 and is discharged from the outlet 12 to the outside of the duct 10.

<7. Modification>
FIG. 9 is an enlarged longitudinal sectional view showing a part of a modification of the blower device 1 according to the exemplary embodiment of the present invention. You may provide the 2nd convex part 18 which protrudes on the lower surface of the cover part 14 at an axial direction lower side. The inner peripheral surface of the second convex portion 18 faces the outer peripheral surface of the shroud 22 in the radial direction.

  The second convex portion 18 blocks airflow from flowing into the gap between the shroud 22 and the cover portion 14. For this reason, it is possible to prevent a part of the air blown outward in the radial direction of the impeller 20 from flowing into the gap between the shroud 22 and the cover portion 14 and to further suppress the occurrence of turbulent flow and backflow in the airflow passage 13. it can. Although both the first convex portion 17 and the second convex portion 18 may be provided, even if only one of them is provided, the blowing efficiency decreases due to the generation of turbulent flow in the air flow passage 13 or the air resistance due to the air flowing backward. Can be prevented. Further, the radial gap between the inner circumferential surface of the second convex portion 18 and the outer circumferential surface of the shroud 22 is narrower than the axial gap between the shroud 22 and the cover portion 14. Therefore, it is possible to block the flow of air that flows backward inward in the radial direction from the gap between the shroud 22 and the cover portion 14.

  FIG. 10 is an enlarged longitudinal sectional view showing the vicinity of the shroud 22 of the air blower 1 of a modification according to an exemplary embodiment of the present invention. The inner peripheral surface 22 b of the shroud 22 has a first inner peripheral surface 221 and a second inner peripheral surface 222, and the first inner peripheral surface 221 is disposed on the upper side in the axial direction than the second inner peripheral surface 222. The first inner peripheral surface 221 is formed parallel to the axial direction, and the second inner peripheral surface 222 is inclined with respect to the axial direction so as to be separated from the central axis A toward the lower side in the axial direction, and toward the inner side in the radial direction. And curved in a convex shape. Moreover, the 1st internal peripheral surface 221 and the 2nd internal peripheral surface 222 are connected through the curved part 223 which curves to convex shape toward radial inside. That is, the lower end of the first inner peripheral surface 221 and the upper end of the second inner peripheral surface 222 are smoothly connected.

  That is, the radial gap between the outer peripheral surface of the first convex portion 17 and the inner peripheral surface 22b of the shroud 22 is formed wider on the lower side in the axial direction than on the upper side in the axial direction.

  For this reason, even when the impeller 20 vibrates in the vertical direction during rotation, the lower end of the inner peripheral surface 22b of the shroud 22 falls below the lower end of the radially outer end of the first convex portion 17 in the axial direction. The air that circulates radially outward along the lower surface of the cover portion 14 is smoothly guided radially outward along the second inner peripheral surface 222 from the lower end of the first convex portion 17. Therefore, even when the impeller 20 vibrates in the vertical direction during rotation, it is possible to suppress a reduction in the blowing efficiency of the blowing device 1.

  Furthermore, the first inner peripheral surface 221 and the second inner peripheral surface 222 are connected via a curved portion 223 that curves in a convex shape toward the radially inner side, and the second inner peripheral surface 222 faces the radially inner side. By forming the convex curve, the air flowing along the inner peripheral surface 22b of the shroud 22 can be smoothly guided radially outward. Thereby, reduction of the ventilation efficiency of the air blower 1 can be suppressed more. Here, the expression that they are connected via the bending portion 223 means that the lower end of the first inner peripheral surface 221 and the upper end of the second inner peripheral surface 222 are smoothly connected.

  Further, by having the first inner peripheral surface 221 formed parallel to the axial direction, the thickness of the shroud 22 in the vertical direction is secured from the upper end of the inner peripheral surface 22b, so that the rigidity of the shroud 22 is reduced. Can be suppressed.

  FIG. 11 is an enlarged longitudinal sectional view showing the vicinity of the shroud 22 of the air blower 1 of the modification according to the exemplary embodiment of the present invention. As shown in FIG. 11, the inner peripheral surface of the shroud 22 is shown. In 22b, a plane parallel to the axial direction may be omitted. In this case, the entire inner peripheral surface 22 b is constituted by the second inner peripheral surface 222. With this configuration, even when the impeller 20 vibrates in the vertical direction during rotation, it is possible to further suppress the reduction of the blowing efficiency of the blower device 1.

  10 and 11, the second inner peripheral surface 222 is formed to be curved in a convex shape toward the radially inner side. However, the second inner peripheral surface 222 is not curved and is disposed on the lower side in the axial direction. You may form by the conical surface which inclines with respect to an axial direction so that it may leave | separate from the central axis A toward it.

  According to the present embodiment, since the inner diameter of the shroud 22 is the same as or larger than the outer diameter of the base plate 21, the upper and lower molds are prevented from interfering with each other, and the molds are respectively placed on the upper and lower sides in the axial direction. Can be removed. Therefore, the impeller 20 can be integrally formed with a mold, and mass productivity can be improved.

  Further, the first convex portion 17 protrudes axially downward from the lower surface of the cover portion 14, and the first convex portion 17 is disposed on the radially inner side with respect to the inner peripheral surface of the shroud 22. Thereby, the first convex portion 17 blocks the air flow path in which the airflow flows into the gap between the shroud 22 and the cover portion 14 and flows backward in the radial direction. For this reason, a part of the air blown to the outer side in the radial direction of the impeller 20 is suppressed from flowing into the gap between the shroud 22 and the cover part 14, and the turbulent flow in the airflow passage 13 and the air by the backflowing air It can prevent that ventilation efficiency falls by resistance.

  Further, the outer peripheral surface of the first convex portion 17 faces the inner peripheral surface of the shroud 22 in the radial direction. As a result, the gap between the shroud 22 and the cover portion 14 is blocked by the first convex portion 17 in the radial direction, and the blowing efficiency is reduced due to the occurrence of turbulent flow in the air flow passage 13 or the air resistance due to the air flowing backward. Can be prevented more. In the present embodiment, the radial gap between the outer peripheral surface of the first protrusion 17 and the inner peripheral surface of the shroud 22 is constant in the axial direction. However, the radial gap between the outer peripheral surface of the first convex portion 17 and the inner peripheral surface of the shroud 22 may not be constant in the axial direction. For example, at least one of the outer peripheral surface of the first convex portion 17 and the inner peripheral surface of the shroud 22 may be curved.

  By providing the second convex portion 18 that protrudes downward in the axial direction from the lower surface of the cover portion 14 and faces the outer peripheral surface of the shroud 22, the second convex portion 18 has an air flow in the gap between the shroud 22 and the cover portion 14. Block the inflow. For this reason, a part of the air blown to the outer side in the radial direction of the impeller 20 is prevented from flowing into the gap between the shroud 22 and the cover part 14, and turbulence is generated in the airflow passage 13 or air resistance due to the air flowing backward. Therefore, it is possible to prevent the air blowing efficiency from being lowered.

  In addition, when a region located radially outside the first convex portion 17 of the blade 23 is a blade first region and a region facing the first convex portion 17 in the vertical direction is a blade second region, The upper end of the blade first region is positioned above the upper end of the radially outer end of the blade second region. Therefore, even when the impeller 20 vibrates in the vertical direction during rotation, it is possible to prevent the upper end of the blade 23 from contacting the first convex portion 17. Further, the blade 23 can be formed larger in the axial direction on the radially outer side than the first convex portion 17, and the amount of air generated by the rotation of the impeller 20 can be increased.

  Further, the lower end of the inner peripheral surface 22 b of the shroud 22 and the lower end of the radially outer end of the first convex portion 17 have substantially the same axial height. Thereby, the air flowing toward the radially outer side along the lower surface of the cover portion 14 is smoothly guided from the lower end of the first convex portion 17 to the lower end of the inner peripheral surface 22b of the shroud 22, and the lower surface of the shroud 22 is It passes through and is blown outward in the radial direction of the impeller 20. Therefore, the air resistance by the 1st convex part 17 can be reduced, and ventilation efficiency can be improved more.

  Note that the lower end of the inner peripheral surface 22 b of the shroud 22 may be positioned on the upper side in the axial direction than the lower end of the radially outer end of the first convex portion 17. Even in this case, the air flowing toward the radially outer side along the lower surface of the cover portion 14 is smoothly guided from the lower end of the first convex portion 17 to the lower end of the inner peripheral surface 22b of the shroud 22, so that the blower 1 blowing efficiency can be improved. Also in this configuration, since the radial gap between the inner peripheral surface 22b of the shroud 22 and the radial outer end of the first convex portion 17 can be narrowed, a part of the air blown out radially outward of the impeller 20 can be obtained. Further, it is possible to suppress the reverse flow from the gap between the shroud 22 and the cover portion 14.

  Further, the radially outer end of the blade 23 extends radially outward from the outer peripheral edge of the base plate 21, and the radially inner end of the blade 23 extends radially inward from the suction port 11, so that the brace 23 is moved in the radial direction. The air volume generated by rotation of the impeller 20 can be increased.

  Further, since the axial gap between the lower end of the base plate protrusion 21 a and the upper surface of the motor housing 16 is narrower than the axial gap between the lower surface of the base plate 21 and the upper surface of the motor housing 16, the base plate protrusion 21 a is connected to the lower surface of the base plate 21. Airflow is prevented from flowing into the axial gap with the upper surface of the motor housing 16. For this reason, part of the air blown to the radially outer side of the impeller 20 is prevented from flowing into the gap between the lower surface of the base plate 21 and the upper surface of the motor housing 16, thereby generating turbulent flow and backflow in the airflow passage 13. It can prevent that ventilation efficiency falls by the air resistance by the air to do.

  Further, the base plate protruding portion 21 a is located at the radially outer edge of the base plate 21. On the upper surface of the motor housing 16, there is provided a groove 16b that faces the base plate protrusion 21a in the vertical direction. The groove 16b is formed to have a larger radial width than the base plate protrusion 21a. That is, on the upper surface of the motor housing 16, a groove portion 16b having a width larger in the radial direction than the base plate protruding portion 21a is formed facing the base plate protruding portion 21a in the vertical direction. Therefore, the base plate protruding portion 21a can be disposed close to the groove portion 16b to further narrow the axial gap between the lower surface of the base plate 21 and the upper surface of the motor housing 16. Accordingly, it is possible to further suppress the flow into the gap between the lower surface of the base plate 21 and the upper surface of the motor housing 16.

  The above-described embodiments and modifications are merely examples of the present invention. The configuration of the embodiment and the modification may be changed as appropriate without departing from the technical idea of the present invention. Further, the embodiment and the plurality of modified examples may be implemented in combination within a possible range.

  Moreover, the air blower 1 of this invention is mounted in the cleaning robot 100 as it is described in FIG. In addition, the air blower 1 may be mounted not only on the cleaning robot 100 but also on a cleaner such as a handy cleaner. Thereby, the vacuum cleaner with high ventilation efficiency is realizable. Moreover, you may mount in apparatuses other than a vacuum cleaner. For example, the blower 1 of the present invention may be mounted on an electronic device such as a personal computer for internal cooling. Moreover, the air blower 1 of this invention may be mounted in other various OA equipment, medical equipment, household appliances, or transport equipment.

  Moreover, about the detailed structure of the air blower 1, you may differ from said embodiment and a modification. Moreover, you may combine suitably each element which appeared in said embodiment and modification in the range which does not produce inconsistency.

  The air blower with high air blowing efficiency of the present invention is suitable for a vacuum cleaner, for example. In addition, the air blower of this invention can be utilized also for another electronic device.

DESCRIPTION OF SYMBOLS 1 ... Air blower, 10 ... Duct, 11 ... Suction inlet, 12 ... Air outlet, 13 ... Airflow path, 14 ... Cover part, 14a ... Cylindrical part, 15. .. peripheral wall part, 15a ... nozzle, 16 ... motor housing, 16a ... concave part, 16b ... groove part, 17 ... first convex part, 18 ... second convex part, 20 .... Impeller, 21 ... Base plate, 21a ... Base plate protrusion, 22 ... Shroud, 22a ... Opening, 22b ... Inner peripheral surface, 23 ... Blade, 23a ... No. 1 blade, 23b ... 2nd blade, 24a, 24b ... radial outer end, 25a, 25b ... projection, 26a, 26b ... inclined surface, 27a, 27b ... inclined surface, 30 ... Motor part, 40 ... Control board, 100 ... Cleaning robot 101 ... Case, 103 ... Intake port, 104 ... Suction passage, 105 ... Dust collection container, 106 ... Filter section, 107 ... Exhaust passage, 108 ... Exhaust Numeral 109, drive wheel 110, front wheel, 221 first inner peripheral surface, 222 second inner peripheral surface, 223 curved portion, A central axis, D ... Dust, D1 ... Outer diameter, D2 ... Inner diameter, F ... Floor surface, R1 ... Air, R2 ... Air, L1 ... Blade first region, L2 ... Blade second area

Claims (11)

An impeller rotatable around a central axis extending in the vertical direction;
A motor part located under the impeller and rotating the impeller around a central axis;
An airflow passage in the internal space, a suction port for flowing fluid into the internal space, a duct for discharging fluid from the internal space, and a duct for accommodating the impeller;
A blower comprising:
The impeller is
A plurality of circumferentially arranged blades;
An annular shroud connecting the upper portions of the plurality of blades and having an opening at a position facing the suction port in the axial direction;
A base plate that connects the lower portions of the plurality of blades and extends in the radial direction;
Have
The duct has a cover portion covering at least a part of the blade and the shroud;
The inner diameter of the shroud is the same as or larger than the outer diameter of the base plate;
The said cover part has a 1st convex part which protrudes in the axial direction lower side from the lower surface of the said cover part, and is distribute | arranged to radial inside rather than the internal peripheral surface of the said shroud, The air blower characterized by the above-mentioned.   The blower according to claim 1, wherein an outer peripheral surface of the first convex portion is opposed to an inner peripheral surface of the shroud in a radial direction.   The blower according to claim 2, wherein a radial gap between the outer peripheral surface of the first convex portion and the inner peripheral surface of the shroud is wider on the lower side in the axial direction than on the upper side in the axial direction. The blade is
A blade first region located radially outward from the first convex portion;
A blade second region facing the first convex portion in the vertical direction;
Have
The blower according to any one of claims 1 to 3, wherein an upper end of the blade first region is located above an upper end of a radially outer end of the blade second region. The blade is
The blower according to any one of claims 1 to 4, further comprising: a protruding portion that protrudes axially upward at a radially outer side than the first convex portion.   The lower end of the inner peripheral surface of the shroud and the lower end of the radially outer end of the first convex portion have substantially the same height in the axial direction. The blower described in 1.   The blower according to any one of claims 1 to 6, wherein a radially outer end of the blade extends radially outward from an outer peripheral edge of the base plate.   The blower according to any one of claims 1 to 7, wherein an inner end in a radial direction of the blade extends radially inward from the suction port. A motor housing located under the base plate;
The base plate has a base plate protrusion that protrudes downward from the lower surface of the base plate,
The axial gap between the lower end of the base plate protrusion and the upper surface of the motor housing is narrower than the axial gap between the lower surface of the base plate and the upper surface of the motor housing. The air blower in any one of. The base plate protrusion is located on a radially outer edge of the base plate,
The blower according to claim 9, wherein a groove portion having a larger radial width than the base plate protrusion is formed on the upper surface of the motor housing so as to face the base plate protrusion in the vertical direction.   A vacuum cleaner comprising the blower device according to any one of claims 1 to 10.

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