JP6405529B2 - Blower - Google Patents

Description

  The present invention relates to an air blower used for an air conditioner, a ventilation fan, or the like.

  Conventionally, this type of blower has been known in which the aerodynamic characteristics and noise characteristics are improved by suppressing the separation of airflow by abruptly increasing the thickness of a part of the blade. (For example, refer to Patent Document 1).

  Hereinafter, the blower will be described with reference to FIG.

  As shown in the sectional view in the rotational direction of the blade 101 in the axial-flow impeller in FIG. 14, a rib 102 extending along the rotational direction leading edge 103 of the blade 101 is provided on the negative pressure side surface of the blade 101.

  The ribs 102 cause creeping vortices in the region 104 shown on the rear side of the ribs 102. The creeping vortex flows on the surface 105 on the upstream side in the rotation axis direction of the blade 101, so that the air flow 106 is hardly separated from the blade 101, and the blowing performance and noise performance are improved.

Japanese Utility Model Publication No. 5-69400

  However, in the above-described conventional blower, the thickness of the portion provided with the ribs is rapidly increased as compared with other portions, so that heat shrinkage is likely to occur during molding and molding is difficult to stabilize. Therefore, it has been a challenge to improve both the blowing performance and noise performance and the stability of molding.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a blower that solves the above-described problems and does not deteriorate the blowing performance and noise performance even when turbulent airflow flows into the impeller while having molding stability. To do.

  A blower device according to the present invention is a blower device including an impeller having a plurality of blades fixed to the outer periphery of a hub, an electric motor that rotates the impeller, and a frame that supports the electric motor. An arc-shaped portion that bulges upstream from the blade leading edge to the blade trailing edge in the rotational axis direction of the blade and a blade front portion provided along the blade leading edge, the blade front portion including the blade front On the surface downstream from the edge in the rotational axis direction of the blade, a protrusion that protrudes with a first arc having a larger curvature than the arc-shaped portion and a recess formed adjacent to the blade trailing edge side of the protrusion A downstream-side delamination suppressing portion configured, an end portion formed on the surface upstream of the blade leading edge in the rotational axis direction of the blade with a second curvature having a larger curvature than the arc-shaped portion, and the end portion It is equipped with an upstream side peeling suppression part composed of a groove part formed on the blade trailing edge side. It is intended to achieve that.

  ADVANTAGE OF THE INVENTION According to this invention, even if it has the stability of shaping | molding, even if the turbulent airflow flows into an impeller, the ventilation apparatus which does not reduce ventilation performance and noise performance can be provided.

Schematic cross-sectional view of the air blower according to Embodiment 1 of the present invention. The top view of the blade of the same blower as seen from the upstream side in the rotation axis direction Cross-sectional view of the blade of the blower Schematic sectional view showing a striped wind speed distribution region generated on the downstream side of the cover of the blower same as above Schematic top view showing the relationship between the blade leading edge of the blade of the air blower same as above and the longitudinal direction of the wire member of the cover (A) Rotational direction cross-sectional view schematically showing airflow separation from the blades of the blower same as the above (b) Rotational direction cross-sectional view schematically showing airflow separation from the blades of the blower same as above Rotational direction cross-sectional view schematically showing the vortex of the airflow generated in the downstream side peeling suppression unit and the upstream side peeling suppression unit of the blower same as above Sectional view in the rotational direction schematically showing the airflow flowing downstream in the rotational axis direction of the blade of the blower same as above Rotational direction sectional view schematically showing the airflow flowing on the upstream side in the rotational axis direction of the blades of the same blower The figure which planarly viewed one sheet | seat of the air blower which concerns on this invention The perspective view of the wing | blade in the case where the air blower which concerns on this invention is equipped with the baffle plate Sectional view in the rotational direction schematically showing the airflow flowing on the suction surface side of the blade when the air blower according to the present invention is provided with a current plate Rotation direction sectional drawing of the wing | blade of the air blower based on this invention Sectional view in the rotational direction showing the impeller blades of a conventional blower

  An air blower according to an embodiment of the present invention is an air blower provided with an impeller having a plurality of blades fixed to the outer periphery of a hub, an electric motor that rotates the impeller, and a frame that supports the electric motor. An arched portion bulging upstream of the blade from the blade leading edge to the blade trailing edge in the rotational axis direction of the blade, and a blade front provided along the blade leading edge, the blade front is A protrusion projecting from a first arc having a larger curvature than the arc-shaped portion on the surface downstream of the blade leading edge in the rotational axis direction of the blade, and adjacent to the blade trailing edge side of the protrusion A downstream-side delamination suppressing portion composed of a hollow portion, an end portion formed with a second arc having a larger curvature than the arc-shaped portion on the surface on the upstream side in the rotational axis direction of the blade from the blade leading edge; And an upstream-side delamination suppressing portion configured by a groove portion formed on the blade trailing edge side of the end portion.

  As a result, even if the airflow flowing into the blade is disturbed, the airflow is hardly separated from the blade surface by the both surfaces of the blade, that is, the downstream side separation suppressing unit and the upstream side separation suppressing unit, so that airflow loss and noise can be reduced. it can.

  And since there is no portion where the wall thickness suddenly increases like a rib, thermal shrinkage during molding hardly occurs. Further, since the blade is curved and connected to the hub, the area of the blade root portion connected to the hub is increased, that is, the connection strength is increased and the resistance to deformation can be increased.

  As described above, it is possible to provide a blower that has molding stability but does not deteriorate the blowing performance and noise performance even when a disturbed airflow flows into the impeller.

  Further, in the air blower according to the embodiment of the present invention, when the airflows having different angles with respect to the rotation shaft flow into the blade, the downstream-side separation suppressing unit is The dent creates a vortex in the dent and suppresses separation of the airflow from the surface on the downstream side in the rotational axis direction of the blade that occurs when the airflow flows at an angle closer to the rotational axis with respect to the blade. The upstream side separation suppressing portion is generated when the end portion and the groove portion generate vortices in the groove portion when the blade rotates, and the airflow flows at an angle closer to the rotation direction with respect to the blade. Airflow separation from the surface on the upstream side in the rotational axis direction of the blade is suppressed.

  If it does in this way, the vortex of an air current can be produced | generated by the hollow part by a protrusion part and a hollow part, and also the vortex of an air current can be produced | generated also by the edge part and a groove part. Thereby, airflow separation can be suppressed even when airflows having different angles with respect to the rotation axis flow into the blades. In other words, in both cases where the airflow flows in the direction of the rotation axis relative to the wing and in the case where the airflow flows in the direction of rotation relative to the wing, the direction of the airflow to be separated from the wing is swirled. Bending in the direction of rotation of the airflow makes it difficult for airflow separation. Thereby, airflow loss and noise can be reduced.

  In the air blower according to the embodiment of the present invention, a line member that has an opening for sucking air from outside is arranged in parallel on the upstream side of the impeller so as to draw air from outside. Are provided with a plurality of covers.

  In this way, since the overall thickness can be reduced, it can be accommodated in the wall, or the protruding thickness to the inside can be reduced. Also, the impeller can be concealed to improve the appearance.

  Further, in the air blower according to the embodiment of the present invention, the blade includes a blade inner peripheral portion in which a tangent direction in a plan view of the blade leading edge has a radial component larger than a rotational component, and a radial component. It is comprised from the blade outer peripheral part with a large rotation direction component, and is equipped with the said upstream side peeling suppression part and the said downstream side peeling suppression part only in the said blade inner peripheral part.

  The surface area of the blade front portion increases due to the formation of the protrusion and the end, and resistance to the flow increases. Since the outer peripheral portion of the blade has a higher peripheral speed than the inner peripheral portion of the blade, the influence of the increase in resistance becomes large. However, in this case, since the protruding portion and the end portion are provided only on the inner peripheral portion of the blade, an increase in resistance to the flow can be suppressed.

  Moreover, the air blower according to the embodiment of the present invention is configured such that the end portion stands on the upstream side in the rotation axis direction of the impeller from the surface of the blade.

  In this way, when the airflow is disturbed and flows at an angle closer to the rotation axis direction of the impeller, when viewed from the groove, the end becomes a wall and the groove becomes a shadow of the end with respect to the flow. For this reason, an airflow comes to flow into an edge part ahead of a groove part. In other words, if the air flows directly into the groove, the air flow cannot flow from the groove to the downstream surface, which increases the flow resistance. It becomes possible to flow along the protruding portion to the downstream surface. Thereby, the increase in resistance to the flow can be suppressed.

  In the air blower according to the embodiment of the present invention, a plurality of rectifying plates formed in a semicircular shape having the same curvature as the second arc are provided at the blade front part so as to partition the groove part.

  If it does in this way, in addition to the effect | action of the peeling suppression by the vortex | eddy_generation produced | generated to a groove part, since airflow flows, adhering to a baffle plate by the Coanda effect, airflow peeling can be suppressed.

(Embodiment 1)
Hereinafter, the air blower according to Embodiment 1 will be described with reference to FIG. FIG. 1 is a schematic sectional view of the blower.

  As shown in FIG. 1, the blower 90 is connected to the impeller 3 in which four blades 1 are fixed around the hub 2 and the downstream side of the impeller 3, and the impeller 3 is rotated about the rotation shaft 7. An electric motor 4 and a frame 5 that supports the electric motor 4 are provided.

  Further, the blower 90 includes a cover 51 connected to the frame 5 on the upstream side in the air flow direction of the impeller 3.

  The cover 51 is disposed close to the impeller 3 in order to reduce the overall thickness of the blower so as to fit within the wall, and to reduce the protruding thickness to the interior in order to improve interior properties. ing. The cover 51 is provided with an opening 52. When the cover 51 is attached to the frame 5, air is sucked into the blower from the outside through the opening 52. A plurality of line members 53 are provided in parallel in the opening 52 so as to partition the opening 52. Thereby, it is hard to see impeller 3 directly from the air blower outside, and the external appearance of the air blower is improved.

  Next, the configuration of the wing 1 will be described in detail with reference to FIGS. FIG. 2 is a plan view of the blade 1 from the upstream side in the rotation axis direction. 3 is a cross-sectional view of the blade 1 cut along the broken line 60a-60b in FIG. 2 as viewed from the radially outer side toward the rotation axis 7 (arrow 64 direction).

  As shown in FIG. 2, the blade 1 rotates around the rotation shaft 7 in the direction indicated by the arrow 65, that is, counterclockwise when viewed from the upstream side. In FIG. 2, the end of the blade 1 in the direction of the rotation axis 7, that is, the contact portion with the hub 2 is a blade root 66. Further, the outer circumferential end of the blade 1 is referred to as a blade tip 67. Further, the upstream end in the rotation direction of the blade 1 is a blade leading edge 8 and the downstream end is a blade trailing edge 17.

  As shown in FIGS. 2 and 3, the blade 1 has an arc-shaped portion 18 that bulges upstream from the blade leading edge 8 to the blade trailing edge 17 in the rotational axis direction of the blade 1. Further, the blade 1 includes a blade front portion 19 provided in a range from the blade root 66 to the blade tip 67 along the blade leading edge 8.

  On the downstream side in the rotation axis direction of the blade front portion 19, a downstream side separation suppressing portion 68 is provided. The downstream-side separation suppressing portion 68 includes a protrusion 22 in which a first arc 21 having a larger curvature than the arc-shaped portion 18 protrudes from the blade leading edge 8 toward the downstream surface 20, and a blade trailing edge 17 side of the protrusion 22. It is comprised with the hollow part 24 formed adjacently. The recess 24 is connected to the downstream surface 20 of the arc-shaped portion 18 on the blade trailing edge 17 side of the projecting portion 22, and varies depending on the difference in curvature between the first arc 21 of the projecting portion 22 and the arc of the arc-shaped portion 18. It is formed by the inflection point.

  An upstream side peeling suppression part 69 is provided on the upstream side of the blade front part 19 in the rotation axis direction. The upstream-side separation suppressing portion 69 includes an end portion 27 formed by projecting the second arc 26 having a larger curvature than the arc-shaped portion 18 toward the upstream surface 25 with the blade leading edge 8 as a base point, and a blade rear of the end portion 27. It is comprised with the groove part 28 formed in the edge 17 side. In the end portion 27, the second arc 26 is located on the blade leading edge 8 side, and the surface 70 is located on the blade trailing edge 17 side. The surface 70 forms a surface parallel to the rotating shaft 7 and the blade leading edge 8 from the upstream end 71 to the downstream end 72 of the end 27. That is, due to the configuration of the surface 70, the end portion 27 is formed so as to stand on the upstream side in the rotation axis direction from the upstream surface 25 in the rotation axis direction.

  Furthermore, a concave-shaped part is located so that the inner side (upstream side in the rotation axis direction) of the protruding part 22 may be dug from the downstream end part 72. The concave shape portion is connected to the upstream surface 25 at a connection point 73 on the blade trailing edge 17 side. The groove 28 is a space formed by the upstream end 71, the surface 70, the downstream end 72, and the connection point 73.

  As an example of the configuration described above, in the first embodiment, the diameter of the impeller 3 is 86 mm, and the curvature ratio of the first arc 21 and the second arc 26 and the curvature of the arc-shaped portion 18 at a radius of 25 mm is 1. : 42. Then, the curvatures of the first arc 21 and the second arc 26 are set to the same curvature so that the protrusion 22 and the end 27 are smoothly connected at the blade leading edge 8, and the diameters of the first arc 21 and the second arc 26 are the same. Is 2.9 times the blade thickness. Further, the bottom surface (concave portion) of the groove portion 28 is formed in a semicircular shape, and its radius is set to 34% of the first arc 21.

  Next, the relationship between the airflow speed and the blade angle in the first embodiment will be described with reference to FIGS. FIG. 4 is a schematic cross-sectional view showing a striped wind speed distribution region generated on the downstream side of the cover. FIG. 5 is a schematic top view showing the relationship between the blade leading edge of the blade and the longitudinal direction of the wire member of the cover. FIG. 6A is a cross-sectional view in the rotational direction schematically showing air flow separation from the blade when the direction of the airflow flowing into the blade is close to the rotational axis direction. FIG. 6B is a rotational direction sectional view schematically showing air flow separation from the wing when the direction of the airflow flowing into the wing is closer to the rotational direction.

  When the impeller 3 is rotated by the electric motor 4, air is sucked into the frame 5 from the outside (upper side in FIG. 4) through the opening 52 of the cover 51 by the action of scratching the air of the blade 1. The sucked air is blown out through the impeller 3 (downward in FIG. 4). Since a plurality of wire members 53 are provided in parallel in the opening 52, air is sucked into the frame 5 through the gaps 54 of the wire members 53. That is, the opening 52 is configured by the plurality of gaps 54.

  Since the air current cannot pass through the line member 53, the wind speed downstream of the line member 53 is slower than the wind speed downstream of the gap 54. Therefore, a striped wind speed distribution region 56 in which the wind speed is distributed in a striped manner is formed on the downstream side of the cover 51 (region surrounded by a broken line in FIG. 4). Since the impeller 3 is provided close to the cover 51, the impeller 3 rotates in the striped wind speed distribution region 56. In other words, when the impeller 3 rotates in the striped wind speed distribution region 56 on the downstream side, it can be said that the cover 51 and the impeller 3 are close to each other. Since the distance between the cover 51 and the impeller 3 is sufficiently large, the impeller 3 rotates in a state where the wind speed is not affected by the line member 53 even on the downstream side, that is, in a region where the wind speed is not distributed. If there is, it cannot be said that it is close.

  Incidentally, as shown in FIG. 5, a plurality of line members 53 are arranged in parallel on the cover 51. On the other hand, the blade 1 rotates counterclockwise around the rotation shaft 7. For this reason, the angle θ formed by the blade leading edge 8 of the blade 1 and the longitudinal direction of the line member 53 can be in the range of 0 to 90 degrees.

  Here, when the angle θ is small, the entire range from the blade root 66 to the blade tip 67 of the blade leading edge 8 simultaneously passes through the high wind speed region or the low wind velocity region in the striped wind velocity distribution region 56.

  On the other hand, when the angle θ is large, a part of the blade leading edge 8 passes through a region where the wind speed is low, and the other part passes through a region where the wind speed is high.

  Here, in the case of passing through a region where the wind speed is high, as shown in FIG. 6A, the wind speed component of the airflow is such that the component 80 toward the downstream side in the rotation axis direction is larger than the rotation direction component 81. The inflow angle of the airflow in this state is an angle closer to the rotation axis direction with respect to the blade.

  Further, when passing through a region where the wind speed is slow, as shown in FIG. 6B, the wind speed component of the airflow is such that the component 82 toward the downstream side in the rotation axis direction is smaller than the rotation direction component 83. The inflow angle of the airflow in this state is an angle closer to the rotational direction with respect to the blade.

  The airflow to the blade 1 includes a plurality of states such as the inflow angle (a), the inflow angle (b), or the inflow angle (intermediate angle) within the range (a) to (b) depending on the angle θ. To do.

  That is, depending on the shape of the cover 51, the angle at which the airflow flows into the blade 1 and the angle of the blade 1 coincide with each other at a certain moment, and the airflow separation from the blade 1 does not occur. As a result, airflow separation occurs.

  Therefore, when the direction of the airflow flowing into the blade 1 fluctuates, it is very difficult to match the airflow inflow angle and the blade 1 angle so that airflow separation from the blade 1 does not occur. Airflow separation from the blade 1 occurs due to such an angle mismatch. Airflow separation deteriorates the air blowing performance and deteriorates the noise performance. Therefore, it is necessary to suppress the airflow separation. In FIG. 6, the tip of the wing 1 has a linear shape for the sake of understanding, but the shape of the wing 1 used in the first embodiment is the shape shown in FIG.

  Next, the operation of the blade front portion 19 will be described in detail with reference to FIGS. FIG. 7 is a cross-sectional view in the rotational direction schematically showing the vortex of the airflow generated in the downstream side peeling suppression unit and the upstream side peeling suppression unit. FIG. 8 is a cross-sectional view in the rotational direction schematically showing the airflow flowing downstream in the rotational axis direction of the blade. FIG. 9 is a cross-sectional view in the rotational direction schematically showing the airflow flowing on the upstream side in the rotational axis direction of the blade.

  As shown in FIG. 7, in the first embodiment, the blade front portion 19 of the blade 1 is provided with a downstream separation suppressing portion 68 and an upstream separation suppressing portion 69.

  When the airflow passes through the recess 24 of the downstream side separation suppressing portion 68, the airflow vortex 32 is generated by the recess. Further, when the airflow passes through the groove portion 28 of the upstream side separation suppressing portion 69, an airflow vortex 35 is generated by the depression of the groove portion 28.

  When a mismatch occurs between the direction of the airflow flowing into the blade 1 and the angle of the blade 1, the airflow away from the blade 1 is bent by the airflow vortices 32 and 35 in the direction of the blade surface. Can be directed. That is, airflow separation from the blade 1 can be suppressed.

  Since vortices are generated on both the upstream side and the downstream side of the blade 1, the direction of the airflow flowing into the blade 1 is closer to the rotational axis direction of the impeller 3 (corresponding to FIG. 6A) and closer to the rotational direction. (Corresponding to FIG. 6B) can be dealt with.

  That is, in the downstream side peeling suppression part 68, as shown in FIG. 8, the recessed part 24 is provided adjacent to the blade trailing edge 17 side of the protrusion part 22. As shown in FIG. For this reason, the airflow flowing along the projecting portion 22 is bent in the direction of the downstream surface 20 of the blade 1 due to the sudden expansion of the flow path in the hollow portion 24, thereby forming a vortex 32 of the airflow in the hollow portion 24. To do.

  The vortex 32 of the airflow is a vortex that rotates in a clockwise direction when viewed from the blade tip 67 side (front side in FIG. 8). When the airflow flowing into the blade 1 is close to the rotational axis direction of the impeller 3, the direction of the airflow going away from the blade front portion 19 of the blade 1 depends on the rotation direction of the vortex 32 of this airflow due to the viscosity of the air. Bent in the direction. The airflow adheres to the downstream surface 20 of the blade 1 and flows along the downstream surface 20.

  Further, in the upstream side separation suppressing portion 69, as shown in FIG. 9, a groove portion 28 is provided on the blade trailing edge 17 side of the end portion 27. For this reason, the airflow flowing along the end portion 27 bends in the direction of the upstream surface 25 of the blade 1 due to the rapid expansion of the flow path in the groove portion 28, thereby forming a vortex 35 of the airflow in the groove portion 28.

  The vortex 35 of the airflow is a vortex that rotates counterclockwise as viewed from the blade tip 67 side (front side in FIG. 9). When the airflow flowing into the blade 1 is close to the rotation direction of the impeller 3, the direction of the airflow that is about to leave the blade front portion 19 of the blade 1 is the direction of the rotation direction of the vortex 35 of this airflow due to the viscosity of the air. To be bent. The airflow adheres to the upstream surface 25 of the blade 1 and flows along the upstream surface 25.

  Thus, providing the air blower which suppresses the air flow separation from the blade | wing 1 by providing the downstream side peeling suppression part 68 and the upstream side peeling suppression part 69, and does not reduce ventilation performance and noise performance. It can be done.

  Then, the upstream side peeling suppression portion 69 and the downstream side peeling suppression portion 68 are formed by a combination of concave and convex shapes, that is, a combination of a concave portion such as the recessed portion 24 and the groove portion 28 and a convex portion such as the protruding portion 22 and the end portion 27. ing.

  Accordingly, the thickness of the blade front portion 19 and the arc-shaped portion 18 can be made the same. That is, in order from the blade leading edge 8 side, an end portion 27 protruding upstream, a groove portion 28 recessed toward the downstream side on the blade trailing edge 17 side, and a protrusion protruding downstream toward the downstream side of the groove portion 28 A recessed portion 24 that is recessed toward the upstream side is disposed on the blade trailing edge 17 side of the portion 22 and the protruding portion 22. Thereby, the blade front portion 19 can be formed with the same thickness as the thickness of the arc-shaped portion 18.

  Thus, since it is not necessary to provide a thick part for airflow peeling suppression, the deformation | transformation by the heat shrink at the time of shaping | molding can be suppressed, and the stability of shaping | molding can be improved. The wing 1 has a curved shape including an arc-shaped portion 18, a protruding portion 22 protruding from the first arc 21, and an end portion 27 protruding from the second arc 26. Since the curved blade 1 is connected to the hub 2, the area of the blade root 66 connected to the hub 2 is increased, that is, the connection strength is increased and the resistance to deformation can be increased. .

  Further, the end portion 27 stands on the upstream side in the rotational axis direction from the upstream surface 25.

  If it does in this way, since the groove part 28 will enter the shadow of the edge part 27 with respect to a flow, an airflow will flow into the edge part 27 before the groove part 28 now. If it flows directly into the groove part 28, the airflow cannot flow from the groove part 28 to the downstream surface 20, and the flow resistance increases. However, the airflow can be easily flowed to the downstream surface 20 along the end portion 27 and the protruding portion 22 by first flowing into the groove portion 28. Moreover, it becomes possible to flow along the downstream surface 20 by the action of the downstream side peeling suppressing portion 68. Thereby, the increase in flow resistance can be suppressed.

(Modification)
In the modification of the embodiment of the present invention, the same components as those in the first embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and only different points will be described. FIG. 10 is a plan view of one blade of the blower according to the present invention.

  As shown in FIG. 10, the blade 1 b may be configured by a blade inner peripheral portion 12 and a blade outer peripheral portion 16. Then, in the blade leading edge 8 in the blade inner peripheral portion 12, the direction of the tangent (arrow 9) in plan view of the blade leading edge 8 is set to a radial component rather than the rotational component 10 in the tangential direction of the blade leading edge. 11 is larger. Then, in the blade leading edge 8 of the blade 1b in the blade outer peripheral portion 16, the direction of the tangent (arrow 13) in the plan view of the blade leading edge 8 is set to be more rotational than the radial component 14 in the tangential direction of the blade leading edge. Component 15 is increased. And the upstream side peeling suppression part 69 and the downstream side peeling suppression part 68 are provided only in the blade inner peripheral part 12. FIG.

  The blade front portion 19 has an increased surface area due to the formation of the protruding portion 22 and the end portion 27, and the resistance to the flow increases. Since the blade outer peripheral portion 16 has a higher peripheral speed than the blade inner peripheral portion 12, the influence of the increase in resistance is increased. However, in this case, since the protrusion 22 and the end 27 are provided only on the blade inner peripheral portion 12, an increase in resistance to the flow can be suppressed.

  Further, the upstream side peeling suppression part 69 and the downstream side peeling suppression part 68 are provided only in the blade inner peripheral part 12, and the connection part 77 between the blade inner peripheral part 12 and the blade outer peripheral part 16 is used as the end point of disappearance. You may form so that it may lose | disappear gradually from 12 to the blade outer peripheral part 16. FIG.

  If it does in this way, the sudden change of the shape from the blade inner peripheral part 12 to the blade outer peripheral part 16 in the blade front part 19 can be reduced. Thereby, airflow separation accompanying a sudden shape change can be suppressed.

  Moreover, as shown in FIG. 11, you may provide the baffle plate 36 for partitioning the groove part 28. As shown in FIG. Specifically, as shown in FIG. 12, a rectifying plate 36 formed in a semicircular shape having the same curvature as the second arc 26 of the blade front portion 19 is arranged in the radial direction of the impeller 3 along the groove portion 28. A plurality are provided.

  In this way, the airflow flowing through the upstream surface 25 flows while adhering to the rectifying plate 36. Then, when the direction of the airflow flowing into the blade 1 fluctuates toward the rotation direction, the airflow flows while adhering to the rectifying plate 36 due to the Coanda effect in addition to the separation suppressing action by the vortex 35 of the airflow. Thereby, airflow separation can be further suppressed.

  As shown in FIG. 13, the end 27b may be configured such that the second arc 26 is positioned on the blade leading edge 8 side and the surface 70b is positioned on the blade trailing edge 17 side. The surface 70b forms a surface inclined from the upstream end portion 71b to the downstream end portion 72 of the end portion 27b toward the blade leading edge 8 side with respect to the rotation axis direction. Further, the upstream end 71 b is rounded with a larger curvature than the second arc 26. Furthermore, a concave-shaped part is located so that the inner side of the protrusion part 22 may be dug from the downstream end part 72b. The concave shape portion is connected to the upstream surface 25 at a connection point 73 on the blade trailing edge 17 side. The groove 28 b is a space formed by the upstream end 71 b, the surface 70 b, the downstream end 72, and the connection point 73.

  In this way, the vortex 35b of the airflow is generated more on the blade leading edge 8 side. The direction of the airflow that is about to leave the blade front portion 19 is bent by the airflow vortex 35 b and adheres to the upstream surface 25. At this time, since the vortex 35b of the airflow is further generated on the blade leading edge 8 side, the airflow can be bent at an initial stage away from the blade front portion 19. Since the airflow can be bent at the initial stage, airflow separation from the blade 1 can be further suppressed.

  The air blower according to the present invention is expected to be used as an air blower for indoor ventilation that requires air blowing capability and quietness.

1, 1b Blade 2 Hub 3 Impeller 4 Electric motor 5 Frame 7 Rotating shaft 8 Blade leading edge 9, 13, 64, 65 Arrows 10, 15, 81, 83 Rotational component 11, 14 Radial component 12 Blade inner peripheral portion 16 Blade outer peripheral portion 17 Blade trailing edge 18 Arc-shaped portion 19 Blade front portion 20 Downstream surface 21 First arc 22 Protruding portion 24 Recessed portion 25 Upstream surface 26 Second arc 27, 27b End portion 28, 28b Groove portion 32, 35, 35b Airflow Vortex 36 of the current plate 51 Cover 52 Opening 53 Line member 68 Downstream side peeling suppression part 69 Upstream side peeling suppression part 90 Blower

Claims (6)

An impeller having a plurality of blades fixed on the outer periphery of the hub;
An electric motor for rotating the impeller;
A blower comprising a frame that supports the electric motor,
An arc-shaped portion bulging from the blade leading edge to the blade trailing edge on the upstream side in the rotation axis direction of the blade, and a blade front provided along the blade leading edge,
The wing front is
A projection formed by a first arc having a larger curvature than the arc-shaped portion on the surface downstream of the blade leading edge in the rotation axis direction of the blade and a recess formed adjacent to the blade trailing edge side of the projection And a downstream side peeling suppression portion configured with a portion,
Consists of an end portion formed with a second arc having a larger curvature than the arc-shaped portion on the upstream surface in the rotational axis direction of the blade from the blade leading edge and a groove portion formed on the blade trailing edge side of the end portion The air blower provided with the upstream peeling suppression part made. When airflows having different angles with respect to the direction of the rotation axis flow into the wing,
The downstream side peeling suppressing portion is
When the blade rotates, the protrusion and the recess generate vortices in the recess, and the airflow flows downstream from the blade in the direction of the rotation axis. Suppresses the separation of airflow from the side surface,
The upstream side peeling suppressing portion is
A surface on the upstream side in the rotation axis direction of the blade that is generated when a vortex is generated in the groove portion by the end portion and the groove portion when the blade rotates, and airflow flows at an angle closer to the rotation direction with respect to the blade. The air blower according to claim 1, which suppresses air flow separation from the air. On the upstream side of the impeller,
The blower according to claim 1, further comprising a cover provided in parallel with a plurality of line members that have an opening for sucking air from outside and are arranged close to the impeller. The wing
The blade inner periphery in which the direction of the tangent in a plan view of the blade leading edge has a radial component larger than the rotational component;
It is composed of a blade outer peripheral portion having a rotational direction component larger than the radial direction component,
Blower according to any one of 3 the downstream separation preventing part and the upstream separation preventing section claims 1 example Bei only in the inner circumferential blade portion. The air blower according to any one of claims 1 to 4, wherein the end portion stands on the upstream side in the rotation axis direction of the impeller with respect to the surface of the blade. The air blower according to any one of claims 1 to 5, wherein a plurality of rectifying plates formed in a semicircular shape having the same curvature as the second arc are provided on the front portion of the blade so as to partition the groove portion.

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