JP2015230114A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner excelling in noise reduction effect.SOLUTION: An air conditioner comprises a centrifugal fan (2) having an impeller (20), a heat exchanger (3) having plural fins (30) arranged at intervals from each other, and an air flow dispersion plate (4) provided between the impeller (20) and the heat exchanger (3). The air flow dispersion plate (4) has a first dispersion part (41) and a second dispersion part (42), which are connected to each other at the upstream side to have a shape convex to the upstream side of an air flow, are extended such that mutual intervals are expanded toward the downstream side of the air flow and disperse the air flow which flows from the impeller (20) toward the heat exchanger (3).

Description

  The present invention relates to an air conditioner including a centrifugal fan.

  DESCRIPTION OF RELATED ART Conventionally, the indoor unit of the air conditioner provided with the centrifugal fan and the heat exchanger arrange | positioned so that the centrifugal fan may be surrounded is known. The heat exchanger has a plurality of fins that are spaced apart from each other and a pipe that penetrates between the fins. Since the airflow blown out from the centrifugal fan collides with the fins from the oblique direction with respect to the fins of the heat exchanger, wind noise is likely to be generated. Specifically, in the indoor unit, on the inner side of the heat exchanger (that is, the side facing the centrifugal fan), the airflow blown out from the centrifugal fan is parallel to or parallel to the fin alignment direction with respect to the fin edge of the heat exchanger. By hitting at a close angle, the airflow may interfere with the edges of the fins and generate noise.

  Patent Document 1 proposes to provide a rectifying plate having two plates protruding inside the heat exchanger in order to reduce wind noise generated when wind blown from the blower is blown to the heat exchanger. ing.

  In patent document 2, in order to prevent the interference sound when the separated vortex generated from the tip of the centrifugal fan flows between the fins of the heat exchanger, the direction opposite to the rotation direction of the centrifugal fan is provided inside the heat exchanger. It has been proposed to provide a plurality of air guide plates that are inclined in parallel to each other and are substantially parallel to each other.

  Patent Document 3 proposes an air conditioner in which a rectifying plate is provided between a heat exchanger and a centrifugal fan, and this rectifying plate has one end in the vertical direction as the other end. It is arrange | positioned so that it may be located in the ventilation direction downstream of a centrifugal fan.

Japanese Patent No. 2661446 JP 2001-099436 A Japanese Patent Application Laid-Open No. 2003-267938

  However, in Patent Document 1 and Patent Document 2, as shown in FIG. 17, the rectifying plate (wind guide plate) 83 is arranged in a posture parallel to the fins 82 a of the heat exchanger 82, and the air flow F <b> 1 is generated by the rectifying plate 83. Since the progress to the downstream side is suppressed, a region 85 where the pressure increases on the upstream side of the rectifying plate 83 is formed. On the other hand, when the centrifugal fan 80 is rotating, a wake region 84 having a high pressure is formed in the vicinity of the trailing edge 81 a of the blade 81, and this region 84 moves accompanying the blade 81. Accordingly, when the blade 81 passes near the rectifying plate 83, the two high pressure regions, that is, the wake region 84 of the blade 81 and the upstream region 85 of the rectifying plate 83 interfere with each other. When the high pressure regions 84 and 85 interfere with each other in this manner, the airflow blown out from the fan 80 becomes difficult to flow, so that the load on the blade 81 increases and pressure fluctuation occurs on the surface of the blade 81. This pressure fluctuation causes noise due to the rotational speed of the fan.

  Further, even in the air conditioner of Patent Document 3, the noise reduction effect is not always sufficiently obtained.

  The objective of this invention is providing the air conditioner excellent in the reduction effect of a noise.

  The air conditioner of the present invention includes a centrifugal fan (2) having an impeller (20), a heat exchanger (3) having a plurality of fins (30) arranged at intervals, and the impeller ( 20) and an airflow dispersion plate (4) provided between the heat exchanger (3). The airflow dispersion plate (4) has a first dispersion part (41) and a second dispersion part (42). The first dispersion part (41) and the second dispersion part (42) are connected to each other on the upstream side so as to have a convex shape on the upstream side of the airflow, and the distance between the first dispersion part (41) and the second dispersion part (42) increases toward the downstream side of the airflow. The air flow extending from the impeller (20) toward the heat exchanger (3) is dispersed.

  In the present invention, the air flow dispersion plate (4) is provided between the impeller (20) and the heat exchanger (3). Thus, by arrange | positioning a member between an impeller (20) and a heat exchanger (3), the flow velocity of the airflow which goes to an heat exchanger (3) from an impeller (20) can be reduced. it can. Thereby, the noise which arises by interference between the airflow blown from the impeller (20) of the centrifugal fan (2) and the fin (30) of the heat exchanger (3) can be reduced. In addition, in the present invention, the airflow dispersion plate (4) has the first dispersion part (41) and the second dispersion part (42), and these dispersion parts (41, 42) are convex on the upstream side of the airflow. Are connected to each other on the upstream side so as to be in the shape of the above, and extend toward the downstream side of the airflow so that the distance between them is widened to disperse the airflow from the impeller (20) toward the heat exchanger (3). Therefore, in this invention, compared with the baffle plate in patent document 3, for example, it is excellent in the noise reduction effect. The reason is as follows.

  In the air conditioner of Patent Document 3 described above, the rectifying plate is disposed so that one of the end portions in the vertical direction is located downstream of the other end portion in the air blowing direction of the centrifugal fan. Therefore, the air flow from the impeller toward the heat exchanger is guided by the rectifying plate to the one end located on the downstream side in the air blowing direction, so that there is a high pressure area near the one end of the rectifying plate. It is formed. Such a high pressure area interferes when the blades of the centrifugal fan pass nearby and causes noise, so that the noise reduction effect by providing the rectifying plate cannot be sufficiently obtained.

  On the other hand, in the present invention, when the airflow from the impeller (20) toward the heat exchanger (3) reaches the vicinity of the airflow dispersion plate (4), the direction along the first dispersion portion (41) and the second Dispersed in the direction along the dispersing portion (42). Therefore, in the present invention, it is possible to suppress the formation of a high pressure region as compared to the case where airflow is locally collected at the one end portion of the rectifying plate as in Patent Document 3, so that the noise reduction effect is achieved. Is excellent.

  In the air conditioner, the impeller (20) includes a hub (21), a shroud (22) provided with an air inlet, and a space between the hub (21) and the shroud (22). A plurality of blades (23) arranged in a direction, and each blade (23) has a portion closer to the hub (21) than the portion closer to the shroud (22). ) Having a rear edge (25) inclined so as to be positioned forward in the rotation direction, and an upstream end where the first dispersion part (41) and the second dispersion part (42) are connected is formed by the shroud. It may be provided at a position closer to the hub (21) than (22).

  In this configuration, in the case of the blade (23) having the rear edge (25) inclined so that the portion on the hub (21) side is positioned in front of the shroud (22) side in the rotational direction of the impeller (20). One of the first dispersion part (41) and the second dispersion part (42) is inclined in a direction along the inclination direction of the rear edge (25). Therefore, when the rear edge (25) passes near the one dispersion part, it interferes with the entire region in the length direction of the dispersion part almost simultaneously, so that the interference sound (NZ sound). May become larger.

  Therefore, in this configuration, the upstream end where the first dispersion part (41) and the second dispersion part (42) are connected (that is, the boundary part between the first dispersion part (41) and the second dispersion part (42)). ) At a position closer to the hub (21) than the shroud (22). Thereby, the length of said one dispersion part (namely, dispersion | distribution part which inclines in the direction along the inclination direction of a trailing edge (25)) of a 1st dispersion | distribution part (41) and a 2nd dispersion | distribution part (42). Can be made smaller than the length of the other dispersion part (that is, the dispersion part that is not inclined in the direction along the inclination direction of the trailing edge (25)). As a result, it is possible to suppress an increase in the interference sound (NZ sound) as described above.

  In the air conditioner, the air flow dispersion plates (4) are connected to each other on the upstream side so as to have a convex shape on the upstream side of the air flow, and extend so as to increase the distance from each other toward the downstream side of the air flow. It has a 3rd dispersion part (43) and a 4th dispersion part (44) which disperse | distribute the airflow which goes to the said heat exchanger (3) from the said impeller (20), The said 1st dispersion part (41), the said 1st The two dispersion portions (42), the third dispersion portion (43), and the fourth dispersion portion (44) may be provided so as to be aligned in the axial direction of the impeller (20).

  In this configuration, when the airflow from the impeller (20) toward the heat exchanger (3) reaches the vicinity of the airflow dispersion plate (4), the direction along the first dispersion part (41) and the second dispersion part (42) and the direction along the third dispersion part (43) and the direction along the fourth dispersion part (44). Therefore, with this configuration, the airflow can be further finely dispersed.

  In the air conditioner, it is preferable that a ventilation part (47) through which an air current passes is provided between the second dispersion part (42) and the third dispersion part (43).

  Since the airflow flowing downstream along the second dispersion part (42) and the airflow flowing downstream along the third dispersion part (43) are closer to each other toward the downstream side, these dispersions The pressure may increase near the downstream end of the portion (42, 43). Therefore, in this configuration, the ventilation part (47) is provided between the second dispersion part (42) and the third dispersion part (43). Therefore, the airflow flowing downstream along the second dispersion part (42) and the airflow flowing downstream along the third dispersion part (43) can pass through the ventilation part (47). It can suppress that a pressure becomes high in the downstream end part vicinity of a part (42, 43).

  As mentioned above, according to the air conditioner of this invention, the air conditioner excellent in the reduction effect of a noise can be provided.

It is sectional drawing which shows the indoor unit of the air conditioner which concerns on 1st Embodiment of this invention. It is the figure which looked at the inside of the indoor unit of the air conditioner which concerns on 1st Embodiment from the downward direction. It is a perspective view which shows the heat exchanger and airflow dispersion | distribution board in the indoor unit of the air conditioner which concerns on 1st Embodiment. It is a side view which shows the heat exchanger and airflow dispersion | distribution board in the indoor unit of the air conditioner which concerns on 1st Embodiment, and is a figure for demonstrating airflow disperse | distributing by an airflow dispersion | distribution board. (A) And (B) is a figure for demonstrating the attachment structure of an airflow dispersion | distribution board. It is a perspective view which shows an example of the impeller which has the blade | wing with which the trailing edge inclines. It is a bottom view which shows the impeller which has the blade | wing with which the trailing edge inclines, a heat exchanger, and an airflow dispersion | distribution board. (A) is schematic which shows the impeller which has the blade | wing with which the trailing edge inclines, (B) is schematic which shows the flow of the air in the impeller which has the blade | wing with which the trailing edge inclines. is there. (C) is a schematic diagram showing an impeller having blades whose rear edges are not inclined, and (D) is a schematic diagram showing air flow in an impeller having blades whose rear edges are not inclined. is there. (A) is a schematic side view which shows the relationship between the blade | wing with which the trailing edge inclines, and an airflow dispersion | distribution board, (B) shows the relationship between the blade | wing with which the trailing edge is not inclined, and an airflow dispersion | distribution board. It is a schematic side view. (A) is a schematic side view which shows the relationship between the trailing edge of the blade | wing shown in FIG. 9, and an airflow dispersion | distribution board, (B) is in the indoor unit of the air conditioner which concerns on the modification 1 of 1st Embodiment. It is a schematic side view which shows the relationship between the trailing edge of a blade | wing and an airflow dispersion | distribution board. It is sectional drawing which shows the indoor unit of the air conditioner which concerns on the modification 2 of 1st Embodiment. It is a side view which shows the heat exchanger and airflow dispersion | distribution board in the indoor unit of the air conditioner which concerns on the modification 3 of 1st Embodiment. It is a perspective view which shows the heat exchanger and airflow dispersion | distribution board in the indoor unit of the air conditioner which concerns on 2nd Embodiment of this invention. It is a side view which shows the heat exchanger and airflow dispersion | distribution board in the indoor unit of the air conditioner which concerns on 2nd Embodiment, and is a figure for demonstrating airflow disperse | distributing by an airflow dispersion | distribution board. It is a side view which shows the heat exchanger and airflow dispersion | distribution board in the indoor unit of the air conditioner concerning the modification 1 of 2nd Embodiment. It is a perspective view which shows the airflow dispersion | distribution board in the modification 1 of 2nd Embodiment. It is a bottom view which shows the heat exchanger and the baffle plate (wind guide plate) in the indoor unit of the air conditioner which concerns on a reference example.

[Air conditioner indoor unit]
Hereinafter, an indoor unit 1 of an air conditioner according to a first embodiment of the present invention will be described in detail with reference to the drawings. An indoor unit 1 shown in FIG. 1 is a ceiling-mounted indoor unit (specifically, a ceiling-embedded indoor unit) installed on a ceiling C. The indoor unit 1 includes a casing 10 having a substantially rectangular parallelepiped shape embedded in an opening provided in a ceiling C, a panel 11 (decorative panel 11) attached to a lower portion of the casing 10, a centrifugal fan 2, and a heat exchanger. 3, one or a plurality of air flow dispersion plates 4, a drain pan 5, a bell mouth 6, and an air filter 8. The centrifugal fan 2, the heat exchanger 3, the airflow dispersion plate 4, the drain pan 5, the bell mouth 6, and the air filter 8 are disposed in the casing 10.

  The panel 11 is slightly larger in plan view than the casing 10 and is exposed indoors in a state of covering an opening provided in the ceiling C. The panel 11 has an air inlet 12 provided at the center thereof, and four air outlets 13 provided around the inlet 12. The suction port 12 is provided with a rectangular suction grill 12a. The four air outlets 13 are provided along the four sides of the panel 11, and each air outlet 13 has an elongated shape extending along the corresponding side.

  The centrifugal fan 2 is a turbo fan and includes an impeller 20 and a fan motor 7 that rotationally drives the impeller 20. As shown in FIGS. 1 and 2, the impeller 20 includes a hub 21, a shroud 22, and a plurality of blades 23. The hub 21 is fixed to the shaft 7 a of the fan motor 7 fixed to the top plate of the casing 10.

  The shroud 22 is disposed so as to face the hub 21 in the axial direction front side F (the suction port 12 side) of the rotation axis A of the impeller 20. The shroud 22 has an air suction port 22a that opens in a circle around the rotation axis A. The outer diameter of the shroud 22 becomes larger toward the rear side R (hub 21 side) in the axial direction.

  The plurality of blades 23 are arranged between the hub 21 and the shroud 22 with a predetermined interval along the circumferential direction of the air suction port 22a. The end of each blade 23 on the front side F in the axial direction is joined to the inner surface of the shroud 22. The end of each blade 23 on the rear side R in the axial direction is joined to the hub 21. As shown in FIG. 2, each blade 23 is a backward blade in which the blade outlet is inclined to the opposite side to the rotation direction D. Each blade 23 has a pressure surface 26 facing radially outward and a suction surface 27 on the opposite side. Each blade 23 has a front edge 24 which is a portion where the air flow guided by the shroud 22 first contacts, and a rear edge 25 which is the rear end of the blade 23 and where the air flow finally contacts.

  The bell mouth 6 is disposed so as to face the shroud 22 on the front side F (the suction port 12 side) in the axial direction of the rotation axis A. The bell mouth 6 has a curved shape that decreases in outer diameter toward the rear side R in the axial direction. The bell mouth 6 has an air suction port 6a that opens in a circle around the rotation axis A. The end of the bell mouth 6 is disposed in the air inlet 22 a of the shroud 22.

  As shown in FIGS. 1 and 2, the heat exchanger 3 is provided so as to surround the periphery of the impeller 20. The heat exchanger 3 has a flat shape with a small thickness, and is disposed at a position through which the airflow F0 blown out from the centrifugal fan 2 passes. In 1st Embodiment shown in FIG. 1, the heat exchanger 3 is arrange | positioned in the radial direction outer side of the impeller 20 in the state which stood up from the dish-shaped drain pan 5 extended along the lower end part. . The heat exchanger 3 is provided so as to be interposed between the impeller 20 and the side wall 10 </ b> A of the casing 10.

  As shown in FIG. 3, the heat exchanger 3 includes a plurality of fins 30 that are spaced apart from each other and a plurality of heat transfer tubes 31 that penetrate the fins 30. In the heat exchanger 3, heat is exchanged between the refrigerant passing through the heat transfer tubes 31 and the air around the fins 30.

  The plurality of heat transfer tubes 31 are arranged so as to be parallel to each other, and the respective end portions are connected to each other via a U-shaped tube or the like. Each heat transfer tube 31 is arranged in a posture orthogonal to the rotation axis A (specifically, a posture parallel to the horizontal direction), but is not limited thereto, and is inclined with respect to a direction orthogonal to the rotation axis A. It may be arranged in a posture.

  Each fin 30 is, for example, a plate-like member, and the plurality of fins 30 are joined to the heat transfer tube 31 by expansion or the like with a gap therebetween. Each of the plurality of fins 30 extends in a direction along the rotation axis A of the impeller 20. In the present embodiment, each of the plurality of fins 30 is arranged in a posture parallel to the rotation axis A of the impeller 20 (specifically, a posture parallel to the vertical direction). You may arrange | position with the attitude | position inclined with respect to the axis | shaft A. FIG. The air blown sideways from the impeller 20 passes through the gap between the adjacent fins 30 and flows to the side wall 10 </ b> A side of the casing 10.

  The drain pan 5 stores water droplets generated in the heat exchanger 3. The stored water is discharged through a drainage path (not shown). The air filter 8 has a size that covers the inlet of the bell mouth 6, and is provided between the bell mouth 6 and the suction grill 12a along the suction grill 12a. The air filter 8 captures dust contained in the air sucked into the casing 10 from the suction grill 12a.

  In the indoor unit 1, when the impeller 20 of the centrifugal fan 2 is rotated by the fan motor 7, an air flow (an air flow F <b> 0 indicated by a two-dot chain line) illustrated in FIG. 1 is generated inside the indoor unit 1. That is, the indoor air sucked from the suction grill 12 a is guided by the bell mouth 6 of the centrifugal fan 2 and flows into the impeller 20. As shown in FIG. 3, the airflow blown out from the impeller 20 has a velocity component in the rotation direction D, proceeds in a direction inclined with respect to the fins 30 of the heat exchanger 3, and toward the fins 30. Flowing. The air that flows into the gaps between the adjacent fins 30 is cooled or heated by exchanging heat with the refrigerant flowing in the heat transfer tubes 31. The heat-exchanged air is supplied into the room through the air outlet 13.

[Airflow dispersion plate]
The airflow dispersion plate 4 has a function of reducing the flow velocity of the airflow from the impeller 20 to the heat exchanger 3 and a function of dispersing the airflow from the impeller 20 to the heat exchanger 3 in at least two directions. As shown in FIGS. 3 and 4, the airflow dispersion plate 4 includes a first dispersion part 41 and a second dispersion part 42. The 1st dispersion | distribution part 41 and the 2nd dispersion | distribution part 42 are mutually connected in the edge part 45 of an upstream so that it may become a convex shape in the upstream of an airflow. The upstream end 45 constitutes a ridge 45 that connects the first dispersion part 41 and the second dispersion part 42. The 1st dispersion | distribution part 41 and the 2nd dispersion | distribution part 42 are extended so that a mutual space | interval may spread toward the downstream of an airflow. The airflow dispersion plate 4 has a substantially V shape in a side view shown in FIG. The airflow dispersion plate 4 can disperse the airflow from the impeller 20 toward the heat exchanger 3 to the first dispersion portion 41 side and the second dispersion portion 42 side.

  As shown in FIGS. 1, 2, and 3, the airflow dispersion plate 4 is provided between the impeller 20 and the heat exchanger 3. In the specific example shown in FIG. 2, the heat exchanger 3 has a straight portion 3 </ b> A that extends linearly along the air outlet 13 and a corner portion 3 </ b> B that connects the adjacent straight portions 3 </ b> A when viewed from the bottom. In the bottom view shown in FIG. 2, when the perpendicular L is drawn from the rotation axis A to the straight portion 3A, the portion where the perpendicular L intersects the straight portion 3A has the shortest distance between the straight portion 3A and the impeller 20. The proximity position P1. In the present embodiment shown in FIGS. 2 and 3, the airflow dispersion plate 4 is provided on the downstream side of the air flow from the proximity position P <b> 1 in the straight portion 3 </ b> A of the heat exchanger 3. The airflow dispersion plate 4 is provided at a position shifted from the proximity position P1 to the downstream side of the air flow in the linear portion 3A of the heat exchanger 3. The indoor unit 1 in the present embodiment includes a plurality of airflow dispersion plates 4, and each airflow dispersion plate 4 is provided at a position shifted from the proximity position P1 to the downstream side of the air flow in the corresponding linear portion 3A. It has been.

  The airflow dispersion plate 4 is disposed so that at least a part thereof faces the rear edge 25 of the blade 23 of the impeller 20 in the radial direction. The airflow dispersion plate 4 is preferably arranged so that at least the ridgeline portion 45 (upstream end portion 45) faces the trailing edge 25 of the blade 23 in the radial direction. In the present embodiment illustrated in FIG. 1, the airflow dispersion plate 4 is provided so as to face the entire area of the trailing edge 25 of the blade 23 in the radial direction, but is not limited thereto. In the present embodiment illustrated in FIG. 1, the airflow dispersion plate 4 has substantially the same length as the trailing edge 25 of the blade 23 in the direction of the rotation axis A, but is not limited thereto. The airflow dispersion plate 4 may be longer than the trailing edge 25 of the blade 23 or shorter than the trailing edge 25 of the blade 23 in the direction of the rotation axis A as in a modification shown in FIG.

  In the present embodiment shown in FIGS. 3 and 4, the airflow dispersion plate 4 is configured by a plate-like member, and therefore, it is difficult to disturb the airflow when it flows into the heat exchanger 3. In this embodiment, the airflow dispersion plate 4 has a shape such that a plate-like member is bent at the upstream end 45. The airflow dispersion plate 4 can be formed, for example, by processing a sheet metal. The air flow dispersion plate 4 can also be obtained by molding a synthetic resin.

  The airflow dispersion plate 4 is disposed in such a posture as to stand up from the heat exchanger 3 toward the impeller 20 side. The width W of the airflow dispersion plate 4 (the dimension of the airflow dispersion plate 4 in the standing direction) is adjusted so that the airflow dispersion plate 4 does not contact the impeller 20. In the present embodiment, the standing direction of the airflow dispersion plate 4 is parallel to the fins 30 adjacent thereto, but is not limited thereto. The rising direction of the airflow dispersion plate 4 may be a direction inclined with respect to the fins 30 adjacent thereto.

  In the present embodiment, the ridge line portion 45 of the airflow dispersion plate 4 is oriented in a direction parallel to the fins 30, but is not limited thereto, and may be oriented in a direction inclined with respect to the fins 30. In the present embodiment, the ridge 45 of the airflow dispersion plate 4 is oriented in a direction perpendicular to the rotation axis A, but is not limited thereto, and is oriented in a direction inclined with respect to the direction orthogonal to the rotation axis A. It may be. The ridgeline part 45 (upstream end part 45) of the airflow dispersion plate 4 is upstream of the air flow than the downstream end part 46 of the first dispersion part 41 and the downstream end part 46 of the second dispersion part 42. Located on the side.

  The first dispersion part 41 has an end 46 on the downstream side of the first dispersion part 41 located on the downstream side of the air flow with respect to the upstream end part 45 (in front of the rotation direction D), and the first dispersion part 41. The axial direction of the rotation axis A (in this embodiment) is such that the downstream end 46 of the portion 41 is positioned on one side (upward in this embodiment) of the rotation axis A with respect to the upstream end 45. (In the vertical direction).

  The second dispersion part 42 has an end 46 on the downstream side of the second dispersion part 42 located on the downstream side (front in the rotational direction D) of the air flow with respect to the end part 45 on the upstream side, and the second dispersion part 42. The downstream end 46 of the portion 42 is inclined with respect to the axial direction of the rotary shaft A so that the downstream end 46 is positioned on the other side (downward in this embodiment) of the rotary shaft A with respect to the upstream end 45. ing.

  In the present embodiment, the length of the first dispersion part 41 (the distance from the upstream end 45 to the downstream end 46 of the first dispersion part 41) is equal to the length of the second dispersion part 42 (upstream side). The distance from the end portion 45 of the second dispersion portion 42 to the end portion 46 on the downstream side of the second dispersion portion 42). Therefore, the upstream end 45 of the airflow dispersion plate 4 is positioned substantially in the middle of the airflow dispersion plate 4 in the direction of the rotation axis A (the vertical direction in FIG. 4). However, the upstream end 45 of the airflow dispersion plate 4 is provided at a position shifted from the middle position of the airflow dispersion plate 4 in the direction of the rotation axis A as in a modification shown in FIG. It may be done.

  Although each of the 1st dispersion | distribution part 41 and the 2nd dispersion | distribution part 42 has a rectangular shape, it is not restricted to this, You may have other shapes other than a rectangular shape. The 1st dispersion | distribution part 41 has 41 A of guide surfaces which faced the upstream (the direction opposite to the rotation direction D) of the flow of air, and the back surface 41B. The guide surface 41 </ b> A guides the airflow blown from the impeller 20 to the end 46 on the downstream side of the first dispersion portion 41. In the present embodiment, the back surface 41B is a surface parallel to the guide surface 41A, but is not limited thereto, and may be a surface inclined with respect to the guide surface 41A.

  The second dispersion part 42 has a guide surface 42A facing the upstream side of the air flow (the direction opposite to the rotation direction D), and a back surface 42B. The guide surface 42 </ b> A guides the airflow blown from the impeller 20 to the end 46 on the downstream side of the second dispersion portion 42. In the present embodiment, the back surface 42B is a surface parallel to the guide surface 42A, but is not limited thereto, and may be a surface inclined with respect to the guide surface 42A. In the present embodiment, the guide surfaces 41A and 42A are flat surfaces, but are not limited thereto. The guide surfaces 41A and 42A may be curved surfaces as in Modification 7 shown in FIG.

  In the present embodiment, the airflow dispersion plate 4 is supported by the heat exchanger 3, but is not limited thereto, and may be supported by, for example, the casing 10. As shown in FIG. 5, the airflow dispersion plate 4 includes one or more legs extending from the first dispersion part 41 and the second dispersion part 42 toward the inside of the heat exchanger 3 (for example, the heat transfer tube 31 side). A portion 48 is provided. The leg part 48 is fixed to the fin 30 or the heat transfer tube 31, for example. In the specific example shown in FIG. 5, the airflow dispersion plate 4 has a pair of legs 48, and each leg 48 has an arcuate recess 48 a along the outer surface of the heat transfer tube 31. The leg portions 48 are fixed to the fins 30 or the heat transfer tubes 31 with the concave portions 48 a of the leg portions 48 in contact with the outer surface of the heat transfer tubes 31.

[Relationship between airflow dispersion plate and trailing edge]
Next, the relationship between the airflow dispersion plate 4 and the trailing edge 25 of the blade 23 will be described. FIG. 6 is a perspective view showing an example of an impeller 20 having blades 23 whose rear edges 25 are inclined. FIG. 7 is a bottom view showing the impeller 20 having the blades 23 whose trailing edge 25 is inclined, the heat exchanger 3 and the airflow dispersion plate 4.

  In the indoor unit 1 according to the present embodiment, each blade 23 may be a so-called three-dimensional blade as shown in FIG. 6 or may be a so-called two-dimensional blade. When each blade 23 is a three-dimensional blade, as shown in FIG. 6, the rear edge 25 of each blade 23 is such that the portion 25 </ b> A on the hub 21 side rotates more than the portion 25 </ b> B on the shroud 22 side. It is inclined with respect to the rotation axis A so as to be positioned in front of D. When each blade 23 is a two-dimensional blade, the trailing edge 25 of each blade 23 is approximately parallel to the rotation axis A.

  FIG. 8A is a schematic diagram showing an impeller 20 having blades 23 whose trailing edge 25 is inclined, and FIG. 8B is an impeller having blades 23 having a trailing edge 25 inclined. FIG. FIG. 8C is a schematic view showing the impeller 20 having the blades 23 whose rear edge 25 is not inclined, and FIG. 8D is an impeller having the blades 23 whose rear edge 25 is not inclined. FIG.

  When the blades 23 are two-dimensional blades as shown in FIGS. 8C and 8D, the airflow guided by the bell mouth 6 and flowing into the impeller 20 mainly flows through the hub 21. The airflow is likely to be peeled off on the shroud 22 side of the negative pressure surface 27 of 23. In the case of a two-dimensional wing, as shown in FIG. 8D, the airflow blown from the impeller 20 tends to be biased toward the hub 21 side rather than the shroud 22 side. The wind speed distribution is such that the wind speed is higher than the wind speed of the airflow flowing through the shroud 22 side.

  On the other hand, when the blade 23 is a three-dimensional wing as shown in FIGS. 8A and 8B, the trailing edge 25 is inclined as shown in FIG. A part of the airflow can flow toward the shroud 22 along the inclination (along the inclined surface). As a result, the separation of the airflow on the shroud 22 side of the suction surface 27 of the blade 23 is suppressed. In the case of a three-dimensional wing, as shown in FIG. 8B, the air velocity distribution of the air flow blown out from the impeller 20 is less biased toward the hub side than the two-dimensional wing, and the shroud 22 is suppressed. There is a tendency to be uniform on the side and the hub 21 side.

  Therefore, the impeller 20 having the three-dimensional blades 23 is blown out from the impeller 20 because the maximum wind speed is lower when the air volume is the same as the impeller 20 having the two-dimensional blades 23. Interference between the airflow and surrounding structures (such as the fins 30 and the partition plates of the heat exchanger 3) is weakened, and peeling is also suppressed as described above, so noise is reduced.

  9A is a schematic side view showing the relationship between the blade 23 whose trailing edge 25 is inclined and the airflow dispersion plate 4, and FIG. 9B is a blade 23 whose trailing edge 25 is not inclined. It is a schematic side view which shows the relationship between the airflow dispersion | distribution board 4 and a flow.

  As described above, in the case of the two-dimensional blade shown in FIG. 9B, the wind speed distribution is biased, so that the wind speed of the airflow flowing along the second dispersion portion 42 located on the hub 21 side is directed to the shroud 22 side. It becomes large compared with the wind speed of the airflow which flows along the 1st dispersion | distribution part 41 located. On the other hand, in the three-dimensional wing shown in FIG. 9A, the wind speed distribution is uniform to some extent on the shroud 22 side and the hub 21 side compared to the two-dimensional wing shown in FIG. The maximum wind speed becomes smaller. Therefore, in the case of the three-dimensional wing shown in FIG. 9A, the air flow is more evenly distributed to the first dispersion portion 41 side and the second dispersion portion 42 side than the two-dimensional wing shown in FIG. 9B. Since they can be dispersed, the effect of reducing wind noise (so-called murmur sound) is great.

  Further, in the blade 23 of the three-dimensional wing shown in FIG. 9A, when the trailing edge 25 of the blade 23 passes in the vicinity of the airflow dispersion plate 4, for example, two interference points X1 and X1 shown in FIG. The trailing edge 25 and the airflow dispersion plate 4 interfere at X2. Similarly, in the blade 23 of the two-dimensional wing shown in FIG. 9B, when the trailing edge 25 of the blade 23 passes in the vicinity of the airflow dispersion plate 4, for example, two interference points X3 shown in FIG. , X4, the trailing edge 25 interferes with the airflow dispersion plate 4.

  In the case of the two-dimensional wing shown in FIG. 9B, the wind speed on the hub 21 side is larger than that on the shroud 22 side, so that when the trailing edge 25 of the blade 23 passes near the interference point X4 on the hub 21 side. The degree of interference between the trailing edge 25 and the airflow dispersion plate 4 tends to increase. On the other hand, in the case of the three-dimensional wing shown in FIG. 9A, the airflow can be evenly distributed to the first dispersion part 41 side and the second dispersion part 42 side to some extent, so that the interference in FIG. Compared with the location X4, the degree of interference between the trailing edge 25 and the airflow dispersion plate 4 is suppressed at the interference locations X1 and X2 in FIG. As a result, the three-dimensional wing has a greater effect of reducing NZ sound than the two-dimensional wing.

  FIG. 10A is a schematic side view showing the relationship between the trailing edge 25 of the blade 23 shown in FIG. 9 and the airflow dispersion plate 4, and FIG. 10B is related to Modification 1 of the first embodiment. It is a schematic side view which shows the relationship between the trailing edge 25 of the blade | wing 23 and the airflow dispersion | distribution board 4 in the indoor unit 1 of an air conditioner.

  In the form shown in FIG. 10A, the upstream end 45 connected to the first dispersion part 41 and the second dispersion part 42 is the downstream end of the first dispersion part 41 in the axial direction of the rotation axis A. It is provided at a substantially middle position between the portion 46 (end portion 46 on the shroud 22 side) and the end portion 46 (end portion 46 on the hub 21 side) on the downstream side of the second dispersion portion 42. On the other hand, in the modified example 1 shown in FIG. 10B, the upstream end 45 where the first dispersion part 41 and the second dispersion part 42 are connected is provided so as to be offset closer to the hub 21 than the shroud 22. It has been.

  In the form shown in FIG. 10A, the direction in which the trailing edge 25 is inclined is close to the direction in which the second dispersion part 42 is inclined. Therefore, when the trailing edge 25 passes in the vicinity of the second dispersion part 42 of the airflow dispersion plate 4, the rear edge 25 interferes almost simultaneously with the entire area of the second dispersion part 42 in the length direction.

  On the other hand, in the first modification shown in FIG. 10B, the upstream end 45 connecting the first dispersion unit 41 and the second dispersion unit 42 (that is, the boundary between the first dispersion unit 41 and the second dispersion unit 42). Part) is provided at a position closer to the hub 21 than the shroud 22. Thereby, the length of the second dispersion part 42 can be made smaller than the length of the first dispersion part 41. Therefore, in the first modification shown in FIG. 10B, compared with the configuration shown in FIG. 10A, the range in which the trailing edge 25 interferes with the second dispersion portion 42 (the length of the second dispersion portion 42). (Corresponding range) can be reduced. As a result, in the first modification, it is possible to suppress an increase in the interference sound (NZ sound) as compared with the form shown in FIG.

  FIG. 11 is a cross-sectional view illustrating an indoor unit 1 of an air conditioner according to Modification 2 of the first embodiment. In the second modification shown in FIG. 11, the airflow dispersion plate 4 is longer than the trailing edge 25 of the blade 23 in the direction of the rotation axis A. In the second modification, the airflow dispersion plate 4 is disposed such that the ridge line portion 45 (upstream end portion 45) faces the rear edge 25 of the blade 23 in the radial direction. In the second modification, the airflow dispersion plate 4 is provided so as to face the entire area of the trailing edge 25 of the blade 23 in the radial direction. An end 46 on the downstream side of the first dispersion portion 41 is positioned further outward (specifically upward) than the end on the hub 21 side at the trailing edge 25 of the blade 23 in the axial direction of the rotation axis A. Yes. An end 46 on the downstream side of the second dispersion part 42 is located further outside (specifically, lower) than the end on the shroud 22 side of the trailing edge 25 of the blade 23 in the axial direction of the rotation axis A. Yes. In the second modification, a wider range of airflow can be dispersed in the first dispersion portion 41 side and the second dispersion portion 42 side in the axial direction of the rotation axis A than in the embodiment shown in FIG.

  FIG. 12 is a side view showing the heat exchanger 3 and the airflow dispersion plate 4 in the indoor unit 1 of the air conditioner according to Modification 3 of the first embodiment. In the third modification, the guide surface 41A of the first dispersion part 41 and the guide surface 42A of the second dispersion part 42 are not flat surfaces but curved surfaces. Specifically, the guide surfaces 41A and 42A are curved surfaces that are convex on the upstream side of the air flow. The back surface 41B of the guide surface 41A and the back surface 42B of the guide surface 42A are curved surfaces that are recessed on the upstream side of the air flow.

[Second Embodiment]
FIG. 13 is a perspective view showing the heat exchanger 3 and the airflow dispersion plate 4 in the indoor unit 1 of the air conditioner according to the second embodiment of the present invention. FIG. 14 is a side view showing the heat exchanger 3 and the airflow dispersion plate 4 in the indoor unit 1 of the air conditioner according to the second embodiment, and is a diagram for explaining that the airflow is dispersed by the airflow dispersion plate 4. It is.

  In the second embodiment shown in FIGS. 13 and 14, the airflow dispersion plate 4 includes a first dispersion portion 41 and a second dispersion portion 42 as in the airflow dispersion plate 4 of the first embodiment. A third dispersion unit 43 and a fourth dispersion unit 44 are also provided. The third dispersion part 43 and the fourth dispersion part 44 are connected to each other on the upstream side so as to have a convex shape on the upstream side of the airflow, and extend so that the mutual distance increases toward the downstream side of the airflow. The 1st dispersion | distribution part 41, the 2nd dispersion | distribution part 42, the 3rd dispersion | distribution part 43, and the 4th dispersion | distribution part 44 are provided so that it may rank with this order in the axial direction of the rotating shaft A of the impeller 20. In the second embodiment, the air flow dispersion plate 4 has a substantially W shape in a side view shown in FIG.

  In the second embodiment, when the airflow from the impeller 20 toward the heat exchanger 3 reaches the vicinity of the airflow dispersion plate 4, the direction along the first dispersion part 41 and the direction along the second dispersion part 42. And in the direction along the third dispersion part 43 and in the direction along the fourth dispersion part 44. Therefore, in the second embodiment, it is possible to disperse the airflow more finely than in the first embodiment.

  FIG. 15 is a side view showing the heat exchanger 3 and the airflow dispersion plate 4 in the indoor unit 1 of the air conditioner according to Modification 1 of the second embodiment. FIG. 16 is a perspective view showing an airflow dispersion plate 4 in Modification 1 of the second embodiment.

  In Modification 1 of the second embodiment shown in FIGS. 15 and 16, a ventilation portion 47 through which an airflow passes is provided between the second dispersion portion 42 and the third dispersion portion 43. The ventilation portion 47 is provided at the boundary portion 46 where the downstream end portion of the second dispersion portion 42 and the downstream end portion of the third dispersion portion 43 intersect. In the specific example shown in FIG. 16, the ventilation portion 47 is a through-hole that is provided in a slit shape along the ridgeline of the boundary portion 46 and penetrates the airflow dispersion plate 4.

[Summary of Embodiment]
As described above, in the first embodiment and the second embodiment, the airflow dispersion plate 4 is provided between the impeller 20 and the heat exchanger 3. Thus, by arranging the members between the impeller 20 and the heat exchanger 3, the flow velocity of the airflow from the impeller 20 toward the heat exchanger 3 can be reduced. Thereby, the noise produced by the interference between the airflow blown from the impeller 20 of the centrifugal fan 2 and the fins 30 of the heat exchanger 3 can be reduced. Moreover, in the first embodiment and the second embodiment, the airflow dispersion plate 4 has a first dispersion part 41 and a second dispersion part 42, and these dispersion parts 41, 42 are convex on the upstream side of the airflow. While being connected to each other on the upstream side so as to have a shape, the air flow from the impeller 20 toward the heat exchanger 3 is dispersed by extending toward the downstream side of the air flow so that the distance between the two is widened. Therefore, in 1st Embodiment and 2nd Embodiment, compared with the baffle plate in patent document 3, for example, it is excellent in the noise reduction effect. That is, when the airflow from the impeller 20 toward the heat exchanger 3 reaches the vicinity of the airflow dispersion plate 4, the airflow is dispersed in the direction along the first dispersion portion 41 and the direction along the second dispersion portion 42. . Therefore, in 1st Embodiment and 2nd Embodiment, it suppresses that a high pressure area | region is formed compared with the case where an airflow gathers locally in said one edge part in a baffle plate like patent document 3. FIG. Because it can, it is excellent in noise reduction effect.

  In the first modification of the first embodiment, each blade 23 has a trailing edge 25 that is inclined so that the portion 25A on the hub 21 side is positioned in front of the shroud 22 side portion 25B in the rotational direction D of the impeller 20. The upstream end 46 where the first dispersion part 41 and the second dispersion part 42 are connected is provided at a position closer to the hub 21 than the shroud 22. In the first modification of the first embodiment, the second dispersion portion 42 is inclined in a direction along the inclination direction of the trailing edge 25. Accordingly, when the trailing edge 25 passes in the vicinity of the second dispersion portion 42, it interferes with the entire region in the length direction of the second dispersion portion 42 almost simultaneously, so that the interference sound (NZ sound). ) May increase. Therefore, in Modification 1 of the second embodiment, the upstream end 46 where the first dispersion part 41 and the second dispersion part 42 are connected is provided at a position closer to the hub 21 than the shroud 22. Thereby, the length of the second dispersion part 42 can be made smaller than the length of the first dispersion part 41. As a result, it is possible to suppress an increase in the interference sound (NZ sound) as described above. Also in the second embodiment, the upstream end 46 where the first dispersion part 41 and the second dispersion part 42 are connected may be provided at a position closer to the hub 21 than the shroud 22.

  In the second embodiment, the airflow dispersion plate 4 includes not only the first dispersion part 41 and the second dispersion part 42 but also the third dispersion part 43 and the fourth dispersion part 44. The third dispersion portion 43 and the fourth dispersion portion 44 are connected to each other on the upstream side so as to have a convex shape on the upstream side of the airflow, and extend so that the distance between them increases toward the downstream side of the airflow. The airflow from 20 toward the heat exchanger 3 is dispersed. The first dispersion part 41, the second dispersion part 42, the third dispersion part 43, and the fourth dispersion part 44 are provided so as to be aligned in the axial direction of the rotation axis A of the impeller 20. In the second embodiment, when the airflow from the impeller 20 toward the heat exchanger 3 reaches the vicinity of the airflow dispersion plate 4, the direction along the first dispersion part 41 and the direction along the second dispersion part 42. And in the direction along the third dispersion part 43 and in the direction along the fourth dispersion part 44. Therefore, in this 2nd Embodiment, compared with 1st Embodiment, an airflow can be disperse | distributed further finely.

  In Modification 1 of the second embodiment, a ventilation portion 47 through which an airflow passes is provided between the second dispersion portion 42 and the third dispersion portion 43. Since the airflow flowing downstream along the second dispersion part 42 and the airflow flowing downstream along the third dispersion part 43 approach each other toward the downstream side, these dispersion parts 42, 43. The pressure may increase in the vicinity of the downstream end of the. Therefore, in the first modification of the second embodiment, the ventilation part 47 is provided between the second dispersion part 42 and the third dispersion part 43. Therefore, the airflow flowing downstream along the second dispersion part 42 and the airflow flowing downstream along the third dispersion part 43 pass through the ventilation part 47 and move downstream from the airflow dispersion plate 4. Therefore, it is possible to suppress an increase in pressure in the vicinity of the downstream end portions of the dispersion portions 42 and 43.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to these embodiment, A various change, improvement, etc. are possible in the range which does not deviate from the meaning.

  In the said embodiment, although the case where the impeller 20 was arrange | positioned with the attitude | position in which the rotating shaft A turned to an up-down direction was illustrated, it is not restricted to this. The impeller 20 may be arranged in a posture in which the rotation axis A is directed in a direction inclined with respect to the vertical direction, or may be arranged in a posture in which the rotation axis A is directed in the horizontal direction.

DESCRIPTION OF SYMBOLS 1 Indoor unit of air conditioner 2 Centrifugal fan 3 Heat exchanger 4 Airflow dispersion plate 20 Impeller 21 Hub 22 Shroud 23 Blade 24 Front edge 25 Rear edge 25A Hub side part in rear edge 25B Shroud side part 30 in rear edge 30 Fin 31 Heat Transfer Tube 41 First Dispersion Part 42 Second Dispersion Part 43 Third Dispersion Part 44 Fourth Dispersion Part 45 Upstream End of Airflow Dispersion Plate 46 Downstream End of Airflow Dispersion Plate 47 Ventilation Part A Impeller Axis of rotation D Rotation direction of impeller

Claims (4)

A centrifugal fan (2) having an impeller (20);
A heat exchanger (3) having a plurality of fins (30) arranged spaced apart from each other;
An air flow dispersion plate (4) provided between the impeller (20) and the heat exchanger (3),
The airflow dispersion plates (4) are connected to each other on the upstream side so as to have a convex shape on the upstream side of the airflow, and extend so as to be spaced apart toward the downstream side of the airflow to extend the impeller (20). An air conditioner having a first dispersion part (41) and a second dispersion part (42) that disperse the air flow toward the heat exchanger (3). The impeller (20)
A hub (21);
A shroud (22) provided with an air inlet;
A plurality of blades (23) arranged in a circumferential direction between the hub (21) and the shroud (22);
Each blade (23) has a trailing edge (25) that is inclined so that a portion on the hub (21) side is positioned in front of the shroud (22) side in the rotational direction of the impeller (20). And
The upstream end where the first dispersion part (41) and the second dispersion part (42) are connected is provided at a position closer to the hub (21) than the shroud (22). The air conditioner according to 1. The airflow dispersion plates (4) are connected to each other on the upstream side so as to have a convex shape on the upstream side of the airflow, and extend so as to be spaced apart toward the downstream side of the airflow to extend the impeller (20). A third dispersion part (43) and a fourth dispersion part (44) for dispersing the air flow toward the heat exchanger (3) from
The first dispersion part (41), the second dispersion part (42), the third dispersion part (43), and the fourth dispersion part (44) are aligned in the axial direction of the impeller (20). The air conditioner according to claim 1 or 2, wherein the air conditioner is provided.   The air conditioner according to claim 3, wherein a ventilation part (47) through which an airflow passes is provided between the second dispersion part (42) and the third dispersion part (43).

Images