JP2005264803A - Blower, heat exchange unit and refrigerator using blower - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blower, a heat exchange unit and a refrigerator which control deterioration of airblasting performance of an impeller and an increase in airblasting noise by controlling turbulance generated at the time of confluence of an air current on the pressure surface side and an air current on the negative pressure surface side at the rear edge. <P>SOLUTION: The air current is deflected axially by a recess 12 on the pressure surface 5 side, and the speed of the air current discharged in the axial direction is increased on the outer peripheral 4f side of the impeller 4. Furthermore, the negative pressure surface 16 side of a projection 14 part is finally made negative pressure in the rotating direction by partially lengthening a chord length by the projection 14 on the rear edge 4b side. Then the flow adheres on the negative pressure surface 16 side by the air current going around and accelerating, and the exfoliation of the air current is controlled. Thus an increase in a shearing stress caused by speed difference is controlled at the time of the confluence of the air current on the pressure surface 5 side and the air current on the negative pressure surface 6 side from the rear edge 4b, and the turbulence generated is controlled. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a heat exchange unit that has a fin tube type heat exchanger such as a water heater and performs heat exchange with air, and a blower used in a refrigerator.

  Conventionally, as this type of blower, there is an axial flow type in which a plurality of blades are disposed around a hub to which a motor is attached (see, for example, Patent Document 1).

  20 to 23 show a conventional blower described in Patent Document 1. FIG. 20 is a front view of the impeller, FIG. 21 is a side view taken along the line XX in FIG. 20, FIG. 22 is a front view of the main part showing the operation of the impeller, and FIG. 23 is a cross-sectional view taken along line YY in FIG. It is. As shown in FIGS. 20 and 21, the impeller 1 includes a hub 3 attached to the motor 2 and a plurality of blades 4 provided around the hub 3. From the front edge 4a to the rear edge 4b of the blade 4, a projecting portion 7 toward the pressure surface 5 is formed in a portion 4c near the outer periphery of the blade 4, and a retreating portion 8 toward the negative pressure surface 6 is formed at the outer peripheral end 4d. The protrusion part 7 and the retreat part 8 are located on the outer peripheral side of the blade 4 with a curvature.

  The operation of the impeller configured as described above will be described below.

First, when the impeller 1 is rotated at a predetermined rotational speed by the motor 2, air flows into the impeller 1, static pressure and dynamic pressure are added by the action of the vanes 4, and the air is discharged out of the impeller 1 and blown. To work. First, a leakage flow from the pressure surface 5 to the suction surface 6 is projected by providing a protrusion 7 toward the pressure surface 5 in the vicinity 4 c of the outer periphery of the blade 4 and a retreating portion 8 toward the suction surface 6 at the outer peripheral end 4 d. By increasing the speed at the start and promoting leakage flow from the pressure surface to the suction surface, pressure fluctuations at the outer periphery (pressure difference between the pressure surface and suction surface) are reduced, and noise increases are suppressed. .
Japanese Patent Laid-Open No. 11-44432

  However, in the configuration as described above, the fin of the fin tube type heat exchanger mounted on the air conditioner, the water heater or the like is condensed or frosted on the impeller 1 or the air path resistance is reduced as in the refrigerator. When used under high conditions, the airflow passing through the pressure surface 5 side of the blade 4 becomes an airflow A having a strong radial component as shown in FIG. The airflow having a strong radial component is blocked by the protruding portion 7 provided on the pressure surface 5 side of the blade 4 and converted into the axial direction, and is discharged from the trailing edge of the blade 4. Therefore, the discharge air velocity in the axial direction from the rear edge on the pressure surface 5 side increases. In addition, since a large circulating vortex (not shown) is generated at the tip of the blade 4 on the suction side under a condition where the air path resistance is high, the airflow sucked into the impeller 1 is disturbed and the airflow along the suction surface 6 Causes delamination. That is, when the airflow between the pressure surface 5 side and the negative pressure surface 6 side at the trailing edge merges, the speed difference increases and the turbulence increases. Therefore, the ventilation performance of the impeller 1 is deteriorated, and there is a problem that the turbulent sound generated increases.

  The present invention solves the above-mentioned conventional problems, and suppresses the turbulence that occurs when the airflow on the pressure surface side and the airflow on the suction surface side at the trailing edge is suppressed, thereby deteriorating the blowing performance of the impeller, and It aims at providing the air blower which suppresses the increase in ventilation noise, a heat exchange unit, and a refrigerator-freezer.

  In order to solve the above-described conventional problems, the present invention provides recesses with one end extending to the vicinity of the rear edge of the blades on the pressure surfaces on the hub side and the outer periphery side of the blades. A protrusion is provided on the edge.

  As a result, on the outer peripheral side of the blades, the mainstream of the main stream becomes larger in the radial direction due to the centrifugal force acting on the airflow between the blades, but the pressure component is deflected from the radial direction to the axial direction by the concave portion on the pressure surface side. The axial airflow velocity discharged from the surface side increases. Furthermore, by partially increasing the chord length by the protrusion on the trailing edge side of the blade, the negative pressure side of the protrusion finally becomes negative with respect to the rotation direction, and the airflow wraps around the protrusion negative pressure side to increase the speed. The flow adheres to the negative pressure side of the protrusion and suppresses separation of the airflow. Accordingly, an increase in shear stress due to a speed difference at the time of merging of the airflow on the pressure surface side and the suction surface side from the blade trailing edge is suppressed, and the generated turbulence is suppressed. Also, on the hub side of the blade, the mainstream is shifted to the outer peripheral side, so that the inflow airflow angle is reduced and the airflow on the suction side is separated, but the chord length is partially increased by the projection on the trailing edge side of the blade. Thus, the negative pressure side of the protrusion finally becomes negative with respect to the rotation direction, and the airflow circulates toward the negative pressure side of the protrusion, thereby reattaching the flow to the negative pressure surface side of the protrusion. Furthermore, the main flow is shifted to the outer periphery due to centrifugal force and the secondary flow acting between the blades due to the pressure difference acting on the pressure surface side and the suction surface side between the blades leads to the center side of the impeller on the pressure surface side on the hub side. Although there is a flow, it is deflected in the axial direction from the central direction by the recess on the pressure surface side and discharged in the axial direction. Therefore, the turbulence generated due to the angle shift at the time of the airflow on the pressure surface side and the suction surface side from the blade trailing edge is suppressed.

  The blower of the present invention can suppress the deterioration of the blowing performance and suppress the increase of blowing noise by suppressing the turbulence generated at the trailing edge of the blade.

  In addition, the heat exchange unit of the present invention is equipped with a blower that suppresses the turbulence generated at the rear edge portion in the unit, thereby suppressing the deterioration of the blowing performance and suppressing the decrease in the air volume passing through the heat exchanger. An increase in blowing noise can be suppressed.

  Moreover, the refrigerator-freezer of this invention suppresses deterioration of ventilation performance by mounting the air blower which suppresses the disorder | damage | failure which generate | occur | produces in a rear edge part in the air channel which supplies cooling air to a storage room, and cooling performance improves can do.

  Moreover, the refrigerator-freezer of this invention suppresses deterioration of ventilation performance by mounting the air blower which suppresses the disturbance which generate | occur | produces in a rear edge part in the air path which supplies air into a machine room, and condensation performance improves. be able to.

  The invention according to claim 1 includes a hub attached to the motor, an impeller comprising a plurality of blades provided around the hub, an orifice surrounding the periphery of the impeller, and the hub side of the blade. An air flow between the blades on the outer peripheral side of the blade is provided on the outer pressure side of the blade by providing a protrusion on the outer pressure side of the blade and providing a protrusion on the hub side of the blade and the rear edge of the outer peripheral side. The centrifugal force acting on the main flow increases the radial component of the blade toward the outer periphery of the blade, but the axial airflow velocity that is deflected from the radial direction to the axial direction and discharged from the pressure surface side is increased by the concave portion on the pressure surface side. To do. Furthermore, by partially increasing the chord length by the protrusion on the trailing edge side of the blade, the negative pressure side of the protrusion finally becomes negative with respect to the rotation direction, and the airflow wraps around the protrusion negative pressure side to increase the speed. The flow adheres to the negative pressure side of the protrusion and suppresses separation of the airflow. Accordingly, an increase in shear stress due to a speed difference at the time of merging of the airflow on the pressure surface side and the suction surface side from the blade trailing edge is suppressed, and the generated turbulence is suppressed. Also, on the hub side of the blade, the mainstream is shifted to the outer peripheral side, so that the inflow airflow angle is reduced and the airflow on the suction side is separated, but the chord length is partially increased by the projection on the trailing edge side of the blade. Thus, the negative pressure side of the protrusion finally becomes negative with respect to the rotation direction, and the airflow circulates toward the negative pressure side of the protrusion, thereby reattaching the flow to the negative pressure surface side of the protrusion. Furthermore, the main flow is shifted to the outer periphery due to centrifugal force and the secondary flow acting between the blades due to the pressure difference acting on the pressure surface side and the suction surface side between the blades leads to the center side of the impeller on the pressure surface side on the hub side. Although there is a flow, it is deflected in the axial direction from the central direction by the recess on the pressure surface side and discharged in the axial direction. Therefore, the turbulence generated due to the angle shift at the time of the airflow on the pressure surface side and the suction surface side from the blade trailing edge is suppressed. Therefore, it is possible to suppress the deterioration of the blowing performance and to suppress the increase of the blowing noise.

  According to the second aspect of the present invention, the length in the substantially extending direction from the rear edge portion of the outer peripheral side of the blade according to the first aspect is longer than the length in the substantially extending direction of the protrusion on the hub side. In the case of an operating point in a large air volume range where the draft resistance is low and the air volume is greater than the stall point, the chord length is partially longer on the outer periphery where the main flow is concentrated, and the air flow around the suction surface side of the protrusion increases. The effect of suppressing the separation of the airflow is increased and the turbulence generated is suppressed.

  According to a third aspect of the present invention, the length of the substantially extended direction from the rear edge of the hub side of the blade of the first aspect of the invention is longer than the length of the substantially extended direction of the protrusion on the outer peripheral side. In the case of an operating point in the low airflow range where the draft resistance is high and the airflow is low, the inflow airflow angle becomes very small and the airflow on the suction side is greatly separated, but the chord length is partly longer. As a result, the airflow that circulates toward the negative pressure side of the projection further increases, reattaches the flow to the negative pressure surface side of the projection, and the effect of suppressing the separation of the airflow increases, thereby suppressing the turbulence that occurs.

  The invention according to claim 4 is such that the depth of the recess provided in the pressure surface on the outer peripheral side of the blade according to claims 1 and 2 is deeper than the depth of the recess provided in the pressure surface on the hub side. A shaft that deflects more airflow from the radial direction to the axial direction on the outer peripheral side where the main flow is concentrated and discharges from the pressure surface side when the operating point is in a large air volume range where the draft resistance is relatively low and the air volume is larger than the stall point. The air flow velocity in the direction further increases, and the separation on the suction surface side is suppressed by the protrusions on the outer peripheral side where the main flow is concentrated, and the increase in shear stress due to the increased flow and speed difference is suppressed, and the generated turbulence is suppressed.

  The invention according to claim 5 is such that the depth of the recess provided in the pressure surface on the hub side of the blade according to claims 1 and 3 is deeper than the depth of the recess provided on the pressure surface side on the outer peripheral side. When the operating point is in the low airflow range where the airflow resistance is relatively high and near the stall point and the airflow is lower, the flow on the hub side toward the impeller center on the pressure surface side is deflected in the axial direction by the recess on the pressure surface side. The turbulence that occurs due to the deviation of the angle at the time of merging with the flow that increases the flow velocity by reattaching on the suction surface side by the protrusion on the hub side and discharging.

  According to the sixth aspect of the present invention, the width of the joint between the rear edge and the protrusion on the outer peripheral side of the blade according to the first, second, third, and fourth aspects is such that the rear edge of the hub and the protrusion When the operating point is in a large airflow range where the draft resistance is relatively low and the airflow is larger than the stall point due to the fact that it is wider than the width of the joint, airflow from the wider area on the outer peripheral side where the mainstream is concentrated to the suction surface side of the protrusion , And exerts an airflow separation suppressing effect on the entire outer peripheral side, thereby suppressing turbulence.

  According to a seventh aspect of the present invention, the width of the joint between the rear edge of the blade and the protrusion of the blade according to the first, second, third, and fourth aspects of the invention is such that Hub that has a relatively large draft resistance and a large airflow angle on the suction side due to a wider airflow at the operating point in the low airflow range where the airflow resistance is relatively high and near the stall point and lower airflow due to being wider than the joint width. The air flow can be made to flow from the wider range on the side to the suction surface side of the protrusion, and the entire hub side exhibits an air flow separation suppressing effect, thereby suppressing turbulence.

  According to the eighth aspect of the present invention, the orifice surrounds the outer periphery of the discharge side of the blades around the impeller of the blower of the first, second, fourth, sixth, and seventh aspects. By improving the air blowing performance, the inflow from the outer periphery of the impeller is also promoted, and the air volume as a blower can be further increased.

  According to a ninth aspect of the present invention, there is provided a blower according to the first, second, and second plate-like mouth rings in which the orifice surrounding the periphery of the first, third, fifth, sixth, and seventh aspects defines the suction side and the discharge side. A swirl flow circulation space having an outer wall surrounding an outer periphery of the first and second plate-like mouth rings and an opening facing the blades of the impeller between the first and second plate-like mouth rings. And there are a plurality of columns provided extending from the opening edges of the first and second plate-like mouth rings in the substantially radial direction of the impeller so that the ventilation resistance is relatively high and the vicinity of the stall point. In the case of an operating point in the low air volume region where the air volume is lower, a swirl flow circulation space in which a part of the air flow having a large radial velocity component is provided on the outer periphery of the impeller from the pressure surface side of the blade on the outer periphery side of the blade. Rotation method with strong circumferential component due to the action of blades in the swirl flow circulation space However, the swirling flow is prevented from being swirled by the plurality of pillars provided extending from the opening edge in the substantially radial direction of the impeller, and from the swirling flow circulation space to the suction surface side of the blade. In order to increase the speed of the airflow flowing along the suction surface side, a part of the airflow passing through the impeller such as discharging to the low pressure part is sucked and exhausted in the swirl circulation space and discharged again to the discharge side, It is possible to suppress turbulence that occurs at the time of merging with the discharge airflow from the pressure surface side. On the blade hub side, the chord length is partially increased by the protrusion on the trailing edge side of the blade to reattach the flow to the suction surface side of the protrusion, and the flow is offset to the outer periphery by centrifugal force. Due to the secondary flow acting between the blades due to the pressure difference acting between the pressure surface side and suction surface side between the blades, the flow toward the center side of the impeller on the pressure surface side on the hub side is caused from the center direction by the concave portion on the pressure surface side. It is deflected in the axial direction and discharged in the axial direction. Therefore, the turbulence generated due to the angle shift at the time of the airflow on the pressure surface side and the suction surface side from the blade trailing edge is suppressed. Therefore, deterioration of the ventilation performance of an impeller can be suppressed as much as possible, and increase in blowing noise can be significantly suppressed.

  A heat exchange unit according to a tenth aspect of the present invention is a fin-tube heat exchanger for exchanging heat with air from the blower according to the first, second, fourth, sixth, seventh, and eighth aspects, and a discharge side of the blower. It is used for a heat exchange unit consisting of a fan guard and a box to be installed in the unit, and a blower that suppresses turbulence that occurs at the rear edge is installed in the unit, thereby suppressing deterioration of the blowing performance and passing through the heat exchanger It is possible to suppress a decrease in the amount of air flow, and to suppress an increase in blowing noise.

  The refrigerator-freezer of Claim 11 uses the air blower of invention of Claim 1, 3, 5, 6, 7, 10 in the air path which supplies cooling air to a store room, and its ventilation performance as an air blower It is possible to suppress the deterioration of the cooling and improve the cooling performance.

  The refrigerator-freezer of Claim 12 uses the air blower of invention of Claim 1, 3, 5, 6, 7, 10 in the air path which supplies air to a machine room, The ventilation performance as an air blower. Deterioration can be suppressed and condensation performance can be improved.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same reference numerals are given to the same configurations as those of the conventional example or the embodiments described above, and detailed descriptions thereof will be omitted. The present invention is not limited to the embodiments.

(Embodiment 1)
1 to 5 show the configuration of the blower in Embodiment 1 of the present invention. 1 to 5, the blower 9 includes an impeller 1 including a motor 2, a hub 3 attached to the motor 2, and a plurality of blades 4 provided around the hub 3. Is provided on the pressure surface 5 of the blade 4 on the hub 4e side and the outer periphery 4f side in the recesses 11 and 12 extending to the vicinity of the rear edge 4b portion of the blade, and the hub 4e side and the outer periphery 4f of the blade 4 are provided. Protrusions 13 and 14 are provided on the rear edge of the side. Here, the depth of the recess 12 provided in the pressure surface 5 on the outer periphery 4f side of the blade 4 is deeper than the depth of the recess 11 provided in the pressure surface 5 on the hub 4e side, and the rear edge 4b portion on the outer periphery 4f side of the blade 4 The length of the protrusion 14 provided in the substantially extending direction is longer than the length of the protrusion 13 provided in the hub 4e side, and the joining width between the rear edge 4b of the outer peripheral 4f side and the protrusion 14 is the rear of the hub 4e side. The configuration is wider than the joint width between the edge 4 b and the protrusion 13.

  The operation and action of the blower configured as described above will be described below.

  First, when the impeller 1 is rotated by the motor 2 in a predetermined rotation direction, air flows into the impeller 1, static pressure and dynamic pressure are applied by the action of the vanes 4, and the air is discharged out of the impeller 1 and blown. To work.

  Here, when the air blower 9 operates at an operating point in a large air volume range where the air flow resistance is relatively low and the air volume is larger than the stall point, the main flow is caused by the centrifugal force acting on the air flow between the blades on the outer periphery 4f side of the blade 4. The offset radial direction component increases toward the outer periphery 4f side, but the axial airflow velocity that is deflected in the axial direction from the radial direction by the concave portion 12 on the pressure surface 5 side and discharged from the pressure surface 5 side increases. Further, by partially extending the chord length by the projection 14 on the trailing edge 4b side of the blade 4, the negative pressure 16 side of the projection 14 finally becomes negative with respect to the rotation direction, and the air flow is negative in the projection 14 portion. By wrapping and accelerating toward the pressure surface 16 side, the flow adheres to the negative pressure surface 16 side of the projection 14 and suppresses separation of the airflow. Therefore, an increase in shear stress due to a speed difference at the time of merging of the airflows on the pressure surface 5 side and the suction surface 6 side from the trailing edge 4b of the blade 4 is suppressed, and the generated turbulence is suppressed. In addition, the main flow is shifted toward the outer periphery 4f side on the hub 4e side of the blade 4, so that the inflow airflow angle is reduced and the airflow on the negative pressure surface 6 side is peeled off. However, the protrusion 4 on the trailing edge 4b side of the blade 4 partially By making the chord length longer, the negative pressure surface 15 side of the projection 13 finally becomes negative with respect to the rotation direction, and the airflow wraps around the negative pressure surface 15 side of the projection 13 and flows to the negative pressure surface 15 of the projection 13 portion. Reattach. Further, the impeller 1 on the pressure surface 5 side on the hub 4e side is caused by the secondary flow acting between the blades due to the main flow being shifted to the outer periphery due to centrifugal force and the pressure difference acting on the pressure surface 5 side and the suction surface 6 side between the blades. However, the flow is deflected in the axial direction from the central direction by the concave portion 11 on the pressure surface 5 side and discharged in the axial direction. Therefore, the turbulence generated due to the angle deviation at the time of the merging of the airflow on the pressure surface 5 side and the suction surface 6 side from the trailing edge 4b of the blade 4 is suppressed. Therefore, it is possible to suppress the deterioration of the blowing performance and to suppress the increase of the blowing noise.

  Further, by increasing the length of the protrusion 14 on the outer peripheral 4f side in the substantially extending direction and increasing the depth of the concave portion 12, the chord length is partially increased on the outer peripheral 4f side where the mainstream is concentrated and the protrusion 14 becomes longer. The airflow that circulates to the suction surface side of the portion 14 increases, the effect of suppressing the separation of the airflow increases, suppresses the turbulence that occurs, and further deflects more airflow from the radial direction to the axial direction on the outer peripheral 4f side where the main flow is concentrated The axial airflow velocity discharged from the pressure surface 5 side is further increased, and the separation is suppressed on the suction surface 6 side by the protrusion 14 on the outer peripheral 4f side where the main flow is concentrated, and the flow is further increased and the shear due to the speed difference It is possible to suppress an increase in stress and to suppress turbulence that occurs.

  Furthermore, by increasing the joining width between the rear edge 4b and the protrusion 14, more airflow can be caused to flow to the suction surface 16 side of the protrusion 14 on the outer peripheral 4f side where the main flow is concentrated, It is possible to suppress an increase in shear stress due to a difference in speed from a flow that is changed from the radial direction to the axial direction by the concave portion 12 on the outer periphery 4f side where the main flow is concentrated and is accelerated in the axial direction, and the generated turbulence can be suppressed.

  Further, as shown in FIG. 6, by increasing the joining width between the rear edge 4b side of the hub 4e side of the blade 4 and the protrusion 13 of the present embodiment, the inflow airflow angle is very small and the suction surface 6 side is reduced. The airflow can be made to flow toward the suction surface 15 side of the protrusion 13 from a wider range on the hub 4e side where the airflow is largely peeled off, and the entire airflow side can be prevented from being peeled and the turbulence can be suppressed.

  Further, as shown in FIG. 7, the orifice 10a surrounds the outer periphery on the discharge 4g side of the blade 4 around the impeller 1 of the present embodiment, thereby suppressing the turbulence generated at the rear edge 4b portion on the outer periphery 4f side. Therefore, the blowing performance as the blade 4 is improved, the inflow from the outer periphery of the impeller 1 is promoted, and the air volume as the blower 9 can be further increased.

(Embodiment 2)
FIG. 8 shows the configuration of the heat exchange unit according to Embodiment 3 of the present invention. In FIG. 8, the heat exchange unit 17 includes a box 18, a fin tube type heat exchanger 19 provided in the box 18, and a surface opposite to the air suction side of the heat exchanger 19 in the box 18. The blower 9 that suppresses the disturbance at the trailing edge 4b of the blade 4 provided in the fan 9 and the fan guard 20 provided on the discharge side of the blower 9 are configured.

  The operation and action of the blower configured as described above will be described below.

  By mounting the blower 9 that suppresses the turbulence generated at the trailing edge 4b of the blade 4 on the heat exchange unit 17, the deterioration of the blowing performance of the blower 9 is suppressed, and the decrease in the amount of air passing through the heat exchanger 19 is suppressed. At the same time, an increase in blowing noise can be suppressed.

(Embodiment 3)
9 to 13 show the configuration of the blower in Embodiment 4 of the present invention.

  9 to 13, one end is provided on the pressure surface 5 on the hub 4 e side and the outer periphery 4 f side of the blade 4 of the blower 21, provided in the recesses 11 a and 12 a extending to the vicinity of the rear edge 4 b portion of the blade, and the hub 4 e side of the blade 4. Protrusions 13a and 14a are provided at the rear edge of the outer periphery 4f. Here, the depth of the recess 11a provided on the pressure surface 5 of the blade 4 on the hub 4e side is deeper than the depth of the recess 12a provided on the pressure surface 5 on the outer periphery 4f side, and the rear edge 4b portion of the blade 4 on the hub 4e side. The length of the protrusion 13a provided in the substantially extending direction is longer than the length of the protrusion 14 provided in the outer peripheral 4f side, and the joining width between the rear edge 4b of the hub 4e side and the protrusion 13a is the rear of the outer peripheral 4f side. The structure is wider than the joint width between the edge 4b and the protrusion 14a.

  The operation and action of the blower configured as described above will be described below.

  First, when the air blower 21 operates near the stall point with relatively high ventilation resistance and at a low air volume operating point where the air volume is low, the air flow between the blades has a strong radial component on the hub 4e side of the blade 4 and the outer periphery. When the main flow is largely deviated toward the 4f side, the inflow airflow angle becomes very small and the airflow on the suction surface 6 side is largely separated, but the length of the protrusion 13a on the hub 4e side of the blade 4 is increased in the lengthwise direction. By making the depth of 11a deeper, the negative pressure surface 15a side of the projection 13a portion finally becomes negative with respect to the rotation direction, and the airflow that wraps around the negative pressure surface 15a side of the projection 13a portion further increases. The flow is reattached to the suction surface 15a. Further, the secondary flow acting between the blades is strengthened by the pressure difference acting on the pressure surface 5 side and the suction surface 6 side between the blades due to the main flow being shifted to the outer periphery due to centrifugal force, and the impeller on the pressure surface 5 side on the hub 4e side. The flow toward the center side of the blade 1 becomes stronger, but the depth of the recess 11a provided on the pressure surface 5 on the hub 4e side of the blade 4 is deeper than the depth of the recess 12a provided on the pressure surface 5 side on the outer periphery 4f side. The flow on the hub 4e side toward the center side of the impeller 1 on the pressure surface 5 side is largely deflected in the axial direction by the concave portion 11a on the pressure surface 5 side and discharged, and on the negative pressure surface 15a side by the protrusion 13a on the hub 4e side. Thus, the effect of suppressing turbulence caused by the deviation of the angle at the time of merging with the flow re-attached and increased in flow velocity can be increased.

  Further, by increasing the joint width between the rear edge 4b and the protrusion 13a, the inflow airflow angle becomes very small and the airflow on the negative pressure surface 6 side to be largely separated from the negative pressure surface 15a side of the protrusion 13a is increased. It is possible to wrap around and suppress an increase in shear stress due to a speed difference from a flow that is changed from the radial direction to the axial direction and accelerated in the axial direction by the concave portion 11a on the hub 4e side, and the generated turbulence can be suppressed. .

  Further, as shown in FIG. 14, by increasing the joining width between the rear edge 4b portion of the outer periphery 4f side of the blade 4 and the protrusion 14a of the present embodiment, more airflow is generated on the outer periphery 4f side where the mainstream is concentrated. Can be caused to flow around the negative pressure surface 16a side of the protrusion 14a, and the shear due to the speed difference from the axially accelerated flow that is changed from the radial direction to the axial direction by the concave 12a portion on the outer peripheral 4f side where the main flow is concentrated. It is possible to suppress an increase in stress and to suppress turbulence that occurs.

(Embodiment 4)
15 to 18 show the configuration of the blower in Embodiment 5 of the present invention.

  An orifice 23 that surrounds the periphery of the impeller 1 of the blower 22 includes first and second plate-like mouth rings 24 and 25 that define a suction side and a discharge side, and first and second plate-like mouth rings 24, An outer wall 26 that surrounds the outer periphery of 25, and a swirl flow circulation space 27 having an opening facing the blade 4 of the impeller 1 between the first and second plate-like mouth rings 24, 25, , There are a plurality of pillars 29 provided extending from the opening edges 28 of the second plate-like mouth rings 24 and 25 in the substantially radial direction of the impeller 1. Also, one end is provided on the pressure surface 5 on the hub 4e side and the outer periphery 4f side of the blade 4 in the recesses 11a and 12a extending to the vicinity of the rear edge 4b portion of the blade, and the rear edge portion on the hub 4e side and the outer periphery 4f side of the blade 4 Are provided with protrusions 13a and 14a. Here, the depth of the recess 11a provided on the pressure surface 5 of the blade 4 on the hub 4e side is deeper than the depth of the recess 12a provided on the pressure surface 5 on the outer periphery 4f side, and the rear edge 4b portion of the blade 4 on the hub 4e side. The length of the protrusion 13a provided in the substantially extending direction is longer than the length of the protrusion 14 provided in the outer peripheral 4f side, and the joining width between the rear edge 4b of the hub 4e side and the protrusion 13a is the rear of the outer peripheral 4f side. The structure is wider than the joint width between the edge 4b and the protrusion 14a.

  The operation and action of the blower configured as described above will be described below.

  When the blower 22 is operated near the stall point with relatively high draft resistance and at a lower air volume operating point where the air volume is lower, a part of the air flow having a large radial velocity component is generated on the outer periphery 4f side of the blade 4 4 is sucked into the swirl flow circulation space 27 provided on the outer periphery of the impeller 1 from the pressure surface 5 side, and the swirl flow swirling in the rotation direction having a strong circumferential component by the action of the blades 4 in the swirl flow circulation space 27. However, swirling of the swirling flow is prevented by a plurality of columns 29 provided extending from the opening edge 28 in the substantially radial direction of the impeller 1, and the low pressure portion on the suction surface 6 side of the blade 4 from the swirling flow circulation space 27. In order to increase the speed of the airflow flowing along the negative pressure surface 6 side, a part of the airflow passing through the impeller 1 is sucked and exhausted in the swirl circulation space 27 and discharged again to the discharge side. At the time of merging with the discharge airflow from the pressure surface 5 side The disturbance to be suppressed. Further, on the hub 4e side of the blade 4, the chord length is partially made longer by the protrusion 13a on the trailing edge 4b side of the blade 4, thereby reattaching the flow to the suction surface 15a side of the protrusion 13a. The flow from the secondary flow acting between the blades toward the center side of the impeller 1 on the pressure surface 5 side on the hub 4e side is deflected in the axial direction from the central direction by the concave portion 11a on the pressure surface 5 side and discharged in the axial direction. Therefore, the turbulence generated due to the angle deviation at the time of the merging of the airflow on the pressure surface 5 side and the suction surface 6 side from the trailing edge 4b of the blade 4 is suppressed. Therefore, deterioration of the ventilation performance of the impeller 1 can be suppressed as much as possible, and an increase in blowing noise of the blower 22 can be significantly suppressed.

(Embodiment 5)
FIG. 19 shows the structure of a refrigerator-freezer according to Embodiment 5 of the present invention.

  In FIG. 19, in the refrigerator 150, the air sucked from the air suction port 102 of the storage chamber 101 by the blower 22 passes through the air passage, is heat-exchanged by the evaporator 103, and is discharged from the air discharge port 104 of the storage chamber 101. Cooled air is supplied to the storage chamber 101. The blower 22 is used in an air passage that supplies cooling air to the storage chamber 101 in the refrigerator-freezer 150. In the present embodiment, these are configured in an upper stage and a lower stage, respectively.

  The machine room 105 includes a compressor 106, an evaporating dish 107, and a condenser 108. The air sucked from the air suction port 109 of the machine room 105 by the blower 22 passes through the air path, is heat-exchanged by the condenser 108, and is discharged from the air discharge port 110 of the machine room 105. The blower 22 is used in an air passage that supplies air into the machine room 105 of the refrigerator.

  With this configuration, the refrigerator-freezer 150 is equipped with the blower 22 that suppresses the turbulence generated at the rear edge portion in the air passage that supplies the cooling air to the storage chamber 101 in the refrigerator-freezer 150, thereby reducing the blowing performance. Therefore, since the amount of air passing through the evaporator 103 is increased, the efficiency of heat exchange is improved, and the cooling performance of the refrigerator-freezer 150 can be improved.

  Moreover, the refrigerator-freezer 150 of this invention mounts the air blower 22 which suppresses the disturbance which generate | occur | produces in a rear edge part in the air path which supplies air in the machine room 105 in the refrigerator-freezer 150, and deterioration of ventilation performance. The amount of air passing through the condenser 108 and the compressor 106 is increased, so that the compressor 106 can be cooled, the efficiency of heat exchange of the condenser 108 is improved, and the condensing capacity of the refrigerator-freezer 150 is improved. it can.

  As described above, since the blower according to the present invention can suppress the disturbance at the trailing edge of the blades at a wide operating point ranging from a large air volume range to a low air volume range, an air conditioner, a computer-related device, Applicable to uses such as ventilation fans and blowers for circulation in storage rooms.

The front view of the air blower in Embodiment 1 of this invention Sectional view of the AA line of FIG. The principal part front view which shows the effect | action of the air blower in Embodiment 1 of this invention. Sectional drawing of the R1h-R1h 'line | wire of FIG. 3 which shows the effect | action of the air blower in Embodiment 1 of this invention. Sectional drawing of the R1t-R1t 'line | wire of FIG. 3 which shows the effect | action of the air blower in Embodiment 1 of this invention. Lumbar front view of other blower according to Embodiment 1 of the present invention Sectional drawing of the principal part of the other air blower in Embodiment 1 of this invention Sectional drawing of the principal part of the heat exchange unit in Embodiment 2 of this invention Front view of a blower in Embodiment 3 of the present invention Sectional view along line B-B 'in FIG. The principal part front view which shows the effect | action of the air blower in Embodiment 3 of this invention. Sectional drawing of the R2h-R2h 'line | wire of FIG. 3 which shows the effect | action of the air blower in Embodiment 3 of this invention. Sectional drawing of the R2t-R2t 'line | wire of FIG. 3 which shows the effect | action of the air blower in Embodiment 3 of this invention. Lumbar front view of other blower according to Embodiment 3 of the present invention Front view of a blower in Embodiment 4 of the present invention Sectional view of the CC line of FIG. Sectional drawing of the DD line | wire of FIG. 16 which shows the effect | action of the air blower in Embodiment 4 of this invention. 17 is a cross-sectional view of the blade of FIG. Side surface longitudinal cross-sectional view of the refrigerator-freezer in Embodiment 5 of this invention Front view of conventional blower XX arrow side view of FIG. Front view of main parts showing the operation of a conventional blower Sectional view of the YY line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Impeller 2 Motor 3 Hub 4 Blade 4b Trailing edge 4e Hub side 4f Outer peripheral side 5 Pressure surface 6 Negative pressure surface 9, 21, 22 Blower 10, 23 Orifice 11, 11a, 12, 12a Recess 13, 13a, 14, 14a Projection DESCRIPTION OF SYMBOLS 17 Heat exchange unit 18 Box 19 Heat exchanger 20 Fan guard 24 1st mouth ring 25 2nd mouth ring 26 Outer wall 27 Swirling flow circulation space 28 Open edge 29 Pillar 101 Storage room 105 Machine room 150 Refrigeration refrigerator

Claims (12)

  A hub attached to the motor; an impeller composed of a plurality of blades provided around the hub; and an orifice surrounding the periphery of the impeller. One end of the blade on the pressure surface on the hub side and the outer peripheral side of the blade A blower provided in a recess extending to the vicinity of the rear edge of the blade and provided with protrusions on the rear edge of the hub side and the outer peripheral side of the blade.   The blower according to claim 1, wherein a length of the protrusion in the substantially extending direction from the rear edge portion on the outer peripheral side of the blade is larger than a length in the substantially extending direction of the protrusion on the hub side.   2. The blower according to claim 1, wherein the length of the protrusion from the rear edge of the blade hub in the substantially extending direction is larger than the length of the protrusion on the outer peripheral side in the substantially extending direction.   The blower according to claim 1 or 2, wherein a depth of the concave portion provided on the pressure surface on the outer peripheral side of the blade is deeper than a depth of the concave portion provided on the pressure surface side on the hub side.   The blower according to claim 1 or 3, wherein the depth of the concave portion provided on the pressure surface of the blade hub is deeper than the depth of the concave portion provided on the pressure surface side on the outer peripheral side.   The width of the junction between the rear edge of the blade on the outer peripheral side and the projection is wider than the width of the junction between the rear edge on the hub and the projection. The blower according to one item.   The width of the junction between the rear edge of the blade on the hub side and the projection is wider than the width of the junction between the rear edge on the outer peripheral side and the projection. The blower according to one item.   The blower according to any one of claims 1, 2, 4, 6, and 7, wherein an orifice surrounding the periphery of the impeller surrounds an outer periphery on a discharge side of the blade.   An orifice surrounding the periphery of the impeller, the first and second plate-like mouth rings defining the suction side and the discharge side, the outer wall surrounding the outer circumference of the first and second plate-like mouth rings, A swirl flow circulation space having an opening facing the blades of the impeller between the first and second plate-like mouth rings, and from the opening edges of the first and second plate-like mouth rings, The blower according to any one of claims 1, 3, 5, 6, and 7, wherein there are a plurality of columns provided extending in a substantially radial direction of the impeller.   A fin tube type heat exchanger for exchanging heat with air provided on the suction side of the blower, a fan guard provided on the discharge side of the blower, and any one of claims 1, 2, 4, 6, 7, 8 A heat exchange unit comprising a box that houses the blower according to claim 1, the heat exchanger, and the blower.   The refrigerator-freezer which used the air blower as described in any one of Claim 1, 3, 5, 6, 7, 10 in the air path which supplies cooling air to a storage room.   The refrigerator-freezer which used the air blower as described in any one of Claim 1, 3, 5, 6, 7, 10 in the air path which supplies air into a machine room.

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