JP2015121379A - Indoor unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an indoor unit capable of suppressing generation of interference noise at cut and raised portions of fins, and edges of the fins of a heat exchanger.SOLUTION: An indoor unit 31 includes a centrifugal fan 61 having a plurality of backward blades, and a heat exchanger 43 disposed on a position where airflow F1 blowing off from the centrifugal fan 61 passes. The heat exchanger 43 has a plurality of fins 43a disposed in parallel with each other while separating from each other in the direction orthogonal to an extending direction of a rotating shaft 13 of the centrifugal fan 61. The fins 43a have projecting cut and raised portions 52, 53 cut and raised from main body parts 51 of the fins 43a. End portions 54 at a centrifugal fan 61 side, of the fins 43a are inclined to a downstream side in a rotating direction E of the centrifugal fan 61. The cut and raised portions 52, 53 are projected to an inclination side of the end portions 54 from surface 51a of the main body portions 51.

Description

  The present invention relates to an indoor unit of an air conditioner.

  Conventionally, as an indoor unit of an air conditioner, a ceiling-mounted indoor unit including a centrifugal fan such as a turbo fan and a heat exchanger arranged to surround the turbo fan is known. Centrifugal fans such as turbofans have a plurality of backward-facing blades arranged circumferentially around the center of rotation. The backward-facing blade is a blade that is positioned rearward in the rotation direction of the centrifugal fan at the outer end opposite to the inner end than the inner end near the rotation center of the centrifugal fan. The heat exchanger has a plurality of fins that are spaced apart from each other and a pipe that penetrates between the fins.

  The airflow blown out from the centrifugal fan passes between the fins of the heat exchanger, and at that time, heat exchange is performed with the refrigerant flowing in the pipe via the fins. At this time, a boundary layer is generated near the surface of the fin among the airflow flowing between the fins. When this boundary layer is generated, there is a possibility that heat transfer between the fins and the airflow flowing near the center between the fins cannot be performed smoothly.

  Therefore, like the indoor unit described in Patent Document 1, the fin is formed with a cut-and-raised portion so that a boundary layer is not formed in the air around the fin of the heat exchanger. The airflow that flows along the surface of the fin becomes turbulent when it hits the cut-and-raised part, and it becomes difficult to generate a boundary layer. Therefore, it is possible to improve heat transfer between the airflow flowing between the fins and the fin. .

JP 2010-249334 A

  However, when the cut-and-raised part is formed in the fin of the heat exchanger as described above, when the air flow blown out from the centrifugal fan flows between the fins, the flow of the fastest part of the air flow (main flow) May hit the cut-and-raised portion of the fin, thereby causing interference noise in the cut-and-raised portion.

  Further, on the inner side of the heat exchanger surrounding the centrifugal fan (that is, the side facing the centrifugal fan), the air flow blown out from the centrifugal fan is parallel to or close to the direction in which the fins are aligned with respect to the edge of the fin of the heat exchanger. By hitting at an angle, the airflow may interfere with the edge of the fin, and interference noise may be generated.

  The present invention has been made in view of the circumstances as described above, and provides an indoor unit capable of suppressing generation of interference noise at the fin raised portion of the heat exchanger and the edge of the fin. With the goal.

  The indoor unit (31) of the present invention includes a centrifugal fan (61) having a plurality of backward-facing blades, and a heat exchanger (43) disposed at a position through which the airflow (F1) blown from the centrifugal fan (61) passes. And the heat exchanger (43) has a plurality of fins (43a) arranged side by side in a direction perpendicular to the direction in which the rotating shaft (13) of the centrifugal fan (61) extends. Each of the plurality of fins (43a) includes a main body portion (43a) and a cut-and-raised portion (52, 53) cut and raised from the main body portion (51). An end portion (54) on the centrifugal fan (61) side of the main body portion (51) of the fin (43a) of the fin (43a) is inclined to the downstream side in the rotational direction (E) of the centrifugal fan (61), and cut and raised. Part (52, 53) is the front Said end from the surface (51a) of the body portion (51) (54), characterized in that the protruding to the side to be inclined.

  In the above configuration, when the air flow (F1) blown out from the centrifugal fan (61) passes between the fins (43a), the flow of the portion with the fastest flow velocity in the air flow (F1) (that is, the main flow (F10)). Flows through a position away from the surface (51a) of the body part (51) from which the cut-and-raised part (52, 53) protrudes by the inclined end part (54) of the body part (51) of the fin (43a). To be guided. Thereby, it is possible to avoid the main flow (F10) flowing along the main body portion (51) and hitting the cut-and-raised portions (52, 53). As a result, it is possible to suppress the occurrence of interference noise in the cut and raised portions (52, 53) of the fin (43a).

  Moreover, the end portion (54) on the centrifugal fan (61) side of the main body portion (51) of at least one fin (43a) is located downstream of the centrifugal fan (61) in the rotational direction (E) (fan wake flow). The airflow (F1) blown out from the fin (43a) and the centrifugal fan (61) by reducing the flow velocity of the airflow (F1) by the end (54) of the fin (43a). Interference with can be weakened. As a result, it is possible to reduce noise generated by the interference between the airflow (F1) blown from the centrifugal fan (61) and the fins (43a) of the heat exchanger (43).

  Further, in the heat exchanger (43), in the position closest to the centrifugal fan (61) and the range downstream thereof, the end (54) of the fin (43a) is rotated in the rotational direction of the centrifugal fan (61). It is preferable to incline toward the downstream side.

  In such a configuration, in the heat exchanger (43), the flow velocity of the airflow (F1) increases at the position closest to the centrifugal fan (61) and the downstream side thereof, so the airflow (F1) and the fins (43a) Noise is most likely to occur due to the interference of the fan, and the end (54) of the fin (43a) in that range is inclined downstream in the rotational direction (E) of the centrifugal fan (61). Noise due to interference between (F1) and the fin (43a) can be effectively reduced. In addition, by limiting the location where the end (54) of the fin (43a) is inclined, the airflow (F1) between the fins (43a) due to the end (54) of the fin (43a) inclined at other locations ) Can be suppressed, and as a result, a decrease in heat exchange capacity can be suppressed.

  Further, the height (H1) from the surface (51a) of the main body portion (51) of the fin (43a) to the tip of the end portion (54) of the fin (43a) is the cut and raised portion (52, 53). ) Is preferably set to be higher than the height (H2, H3).

  According to this configuration, the main flow (F10) of the airflow (F1) is prevented from hitting the cut and raised portions (52, 53) by the inclined end portion (54) of the main body portion (51) of the fin (43a). It is possible to guide with certainty.

  Furthermore, a plurality of rows of the heat exchangers (43, 63) are arranged side by side along a direction away from the centrifugal fan (61), and the first row of heat exchangers (43) close to the centrifugal fan (61). Preferably, only the end (54) of the fin (43a) is inclined.

  Here, in a configuration including a plurality of rows of heat exchangers (43, 63), the end (54) of the fin (43a) of only the first row of heat exchangers (43) close to the centrifugal fan (61). Is inclined, the interference between the fin (43a) and the air flow (F1) blown out from the centrifugal fan (61) can be weakened, and the air flow (F1) and the fin (43a) of the heat exchanger (43) It is possible to reduce noise caused by interference between the two.

  Moreover, the tips (74) of the fins (63a) of the heat exchanger (63) are not inclined, so that the tips (74) of the fins (63a) of the heat exchanger (63) are inclined. It is possible to suppress a reduction in heat exchange capacity due to the generation. Moreover, since the end (54) of the fin (43a) of the heat exchanger (43) in the first row is inclined, the airflow (F1) passes through the fin (43a). Since the flow velocity of F1) decreases, when the airflow (F1) passes between the fins (63a) of the heat exchangers (63) in the second and subsequent rows, the airflow (F1) and the fins (63a) Interference is greatly reduced, and noise generation due to interference can be further reduced.

  As described above, according to the indoor unit of the present invention, it is possible to suppress the generation of interference noise at the fin raised portion and the edge of the fin of the heat exchanger.

It is a longitudinal cross-sectional view which shows the inside of the indoor unit of the air conditioner concerning embodiment of this invention. It is the figure which looked at the impeller of FIG. 1, and its peripheral part from the downward direction. It is a partial expansion perspective view of the heat exchanger of FIG. It is the figure which looked at the fin of FIG. 3 from the direction which piping penetrates. It is the figure which looked at the fin of FIG. 4 from the upstream of the airflow F1. FIG. 5 is a cross-sectional view taken along line VI-VI of the fin of FIG. 4 and shows a state where an air flow F1 flows between the fins. FIG. 5 is a cross-sectional view of the fin of FIG. 4 taken along the line VII-VII, showing a state in which an airflow F1 flows between the fins. It is explanatory drawing which shows the state which airflow strikes the fin of a heat exchanger. It is the graph which compared the magnitude | size of the interference noise by the front edge of the fin of a heat exchanger when the bending direction of the front edge of a fin was made into the same direction as the case where it was the opposite direction with respect to the direction of an airflow. It is an enlarged view which shows arrangement | positioning of the heat exchanger in the indoor unit provided with the heat exchanger of multiple rows which concerns on other embodiment of this invention.

  Hereinafter, an indoor unit of an air conditioner according to an embodiment of the present invention will be described in detail with reference to the drawings.

  An indoor unit 31 shown in FIG. 1 is a ceiling-embedded cassette indoor unit. The indoor unit 31 includes a substantially rectangular parallelepiped housing 33 embedded in an opening provided in the ceiling C, and a decorative panel 47 attached to the lower portion of the housing 33. The decorative panel 47 is slightly larger in plan view than the housing 33 and is exposed indoors in a state of covering the opening of the ceiling C. The decorative panel 47 has a rectangular suction grill 39 provided in the center thereof, and four elongated rectangular outlets 37 provided along each side of the suction grill 39.

  The indoor unit 31 includes a centrifugal fan 61 provided with an impeller 23, a fan motor 11 that rotationally drives the impeller 23, a heat exchanger 43 that surrounds the outside of the impeller 23, a drain pan 45, and an air filter 41. I have.

  The centrifugal fan 61 is a turbo fan and includes an impeller 23 and a bell mouth 25.

  As shown in FIGS. 1 and 2, the impeller 23 includes a hub 15, a shroud 19, and a plurality of blades 21. The hub 15 is fixed to the rotating shaft 13 of the fan motor 11 fixed to the top plate of the housing 33.

  The shroud 19 is disposed to face the front side F in the axial direction A of the rotary shaft 13 with respect to the hub 15. The shroud 19 has an air suction port 19 a that opens in a circle around the rotation shaft 13. The outer diameter of the shroud 19 becomes larger toward the rear side R.

  The plurality of blades 21 are arranged between the hub 15 and the shroud 19 at a predetermined interval along the circumferential direction of the air suction port 19a. The front F end of each blade 21 is joined to the inner surface of the shroud 19. The end of the rear side R of each blade 21 is joined to the hub 15. Each blade 21 is a backward-facing blade that is inclined in the opposite direction (backward) in the rotation direction B (see FIG. 2) with respect to the radial direction of the hub 15.

  The bell mouth 25 is disposed to face the front side F in the axial direction A with respect to the shroud 19. The bell mouth 25 has a curved shape whose outer diameter decreases toward the rear side R.

  As shown in FIGS. 1 and 2, the heat exchanger 43 has a flat shape with a small thickness, and is aligned along the flow direction of the airflow F0 at a position where the airflow F0 blown out from the centrifugal fan 61 passes. Is arranged in. Specifically, the heat exchanger 43 has an impeller 23 of the centrifugal fan 61 so as to surround the periphery of the impeller 23 while standing upward from a dish-shaped drain pan 45 extending along the lower end portion thereof. Are arranged in the radial direction. In other words, the heat exchanger 43 is arranged at a position through which the airflow F0 blown out from the centrifugal fan 61 passes.

  Specifically, as shown in FIG. 3, the heat exchanger 43 includes a plurality of fins 43 a that are spaced apart from each other and a plurality of pipes 43 b that penetrate the fins 43 a. The plurality of pipes 43b are arranged so as to be parallel to each other, and the respective ends are connected to each other via a U-shaped pipe or the like. The fins 43a are joined to each pipe 43b by brazing or the like with a gap 43c therebetween. In the heat exchanger 43, heat is exchanged between the refrigerant passing through the pipe 43b and the air around the fins 43a.

  As shown in FIG. 3, the fins 43 a of the heat exchanger 43 are in a direction perpendicular to the direction in which the rotating shaft 13 of the impeller 23 of the centrifugal fan 61 extends (the vertical direction in FIG. 3), and the impeller The air flow F <b> 1 blown out from the heat exchanger 23 is arranged side by side at a pitch S in the direction X perpendicular to the flow direction passing through the inside of the heat exchanger 43.

  4-7, the fin 43a has the main-body part 51 and two types of cut-and-raised parts 52 and 53 which protrude from the surface of the said main-body part 51. As shown in FIG. The cut and raised portions 52 and 53 are formed by being cut and raised from the main body portion 51 of the fin 43a.

  Ends 54 on the impeller 23 side of the centrifugal fan 61 of the main body portions 51 of all the fins 43a in the heat exchanger 43 are inclined toward the downstream side in the rotational direction E (see FIGS. 3 and 6 to 7) of the centrifugal fan 61. In other words, the air flow F1 blown from the impeller 23 of the centrifugal fan 61 in the tangential direction of the outer periphery of the centrifugal fan 61 (specifically, the air flow F13 immediately before entering between the fins 43a (see FIGS. 6 to 7)). It is inclined to the downstream side of the fan, that is, in the direction opposite to the fan wake. Thereby, when the air flow F1 blown out from the centrifugal fan 61 passes between the fins 43a, the main flow F10 which is the flow of the fastest part of the air flow F1 is the inclined end portion 54 of the main body portion 51 of the fin 43a. Thus, the cut-and-raised portions 52 and 53 are guided so as to flow in positions away from the surface 51a of the main body portion 51 from which the cut-and-raised portions 52 and 53 protrude.

  Further, the height H1 from the surface 51a of the main body portion 51 of the fin 43a to the tip of the inclined end portion 54 of the fin 43a is equal to the height H2 of the cut-and-raised portion 52 shown in FIG. 6 and the cut shown in FIG. The height H3 of the raising portion 53 is set higher.

  The cut-and-raised portions 52 and 53 are respectively downstream of the air flow F1 blown out from the impeller 23 of the centrifugal fan 61 in the tangential direction of the outer periphery of the centrifugal fan (61), that is, from the surface 51a of the main body portion 51 to the end portion 54. Protrudes toward the inclined side.

  Specifically, as shown in FIG. 4, the cut-and-raised portion 52 is disposed on the upstream side of the airflow F1 passing between the fins 43a so as to surround the periphery of the pipe 43b that penetrates the main body portion 51 of the fins 43a. They are arranged on both the left and right sides and the left and right sides on the downstream side. As shown in FIGS. 4 to 6, the cut-and-raised part 52 is separated from the main body part 51 and extends in parallel with the main body part 51, and a pair of connecting parts that connect the flat plate part 52 a and the main body part 51. 52b. The pair of connecting portions 52b are arranged apart from each other in a direction orthogonal to the direction in which the airflow F1 (particularly, the main flow F10) flows. An air flow passage 52c extending in the direction in which the air flow F1 flows is formed by the flat plate portion 52a and the pair of connecting portions 52b. Further, an opening 51 a generated by the cut-and-raised portion 52 is formed at a position facing the cut-and-raised portion 52 of the main body portion 51. The opening 51 a communicates with the air flow passage 52 c of the cut and raised portion 52. As shown in FIG. 6, the branch flow F11 branched from the main flow F10 of the airflow F1 flowing between the fins 43a flows along the main body portion 51 of the fin 43a, and the air flow passage 52c formed by the cut-and-raised portion 52 and The direction of flow is disturbed by meandering by passing through the opening 51a. Thereby, generation | occurrence | production of the boundary layer which inhibits heat transfer with the branch flow F11 of the airflow F1 and the fin 43a in the surface of the main-body part 51 of the fin 43a is avoided.

  As illustrated in FIG. 4, the cut-and-raised portions 53 are respectively disposed between the pipes 43 b that penetrate the main body portion 51. As shown in FIGS. 4 to 5 and 7, the cut-and-raised portion 53 is a plate-like portion that is inclined obliquely in a direction away from the main body portion 51 as it goes from the main body portion 51 toward the upstream side of the air flow F <b> 1. In the main body 51, an opening 51 b generated by the cut and raised portion 53 is formed at a position facing the cut and raised portion 53. As shown in FIG. 7, the branch flow F12 branched from the main flow F10 of the airflow F1 flowing between the fins 43a flows along the main body portion 51 of the fin 43a and is guided by the cut-and-raised portion 53 to open the main body portion 51. The direction of flow is disturbed by meandering by passing through 51b. Thereby, generation | occurrence | production of the boundary layer which inhibits heat transfer with the branch flow F12 of the airflow F1 and the fin 43a in the surface of the main-body part 51 of the fin 43a is avoided.

  Other configurations of the indoor unit 31 are the same as those of a conventional ceiling-embedded cassette indoor unit. Specifically, as shown in FIG. 1, the drain pan 45 stores water droplets generated in the heat exchanger 43. The stored water is discharged through a drainage path (not shown). The air filter 41 has a size that covers the inlet of the bell mouth 25, and is provided along the suction grill 39 between the bell mouth 25 and the suction grill 39. The air filter 41 captures dust contained in the air sucked into the housing 33 from the suction grill 39.

  In the indoor unit 31 configured as described above, when the fan motor 11 is driven, the impeller 23 of the centrifugal fan 61 rotates to generate the air flow F0 shown in FIG. Is possible. That is, the indoor air sucked from the suction grill 39 passes through the inside of the bell mouth 25 of the centrifugal fan 61 toward the impeller 23. The air that has reached the impeller 23 is cooled or heated by blowing out radially outward of the impeller 23 and exchanging heat with the refrigerant when sequentially passing through the heat exchanger 43 disposed outside the impeller 23. The Thereafter, the heat-exchanged air is supplied into the room through the air outlet 37.

  As described above, in the indoor unit 31 of this embodiment, the end portion 54 on the centrifugal fan 61 side in the main body portion 51 of the fin 43 a is inclined toward the downstream side in the rotational direction of the centrifugal fan 61. In addition, the cut-and-raised portions 52 and 53 protrude from the surface 51 a of the main body portion 51 to the side where the end portion 54 is inclined. With such a configuration, when the air flow F1 blown out from the centrifugal fan 61 passes between the fins 43a, the main flow F10 of the air flow F1 is cut and raised by the inclined end portion 54 of the main body portion 51 of the fin 43a. 53 is guided so as to flow in a position away from the surface 51a of the main body portion 51 from which the body 53 protrudes. Accordingly, it is possible to avoid the main flow F10 from flowing along the main body portion 51 and hitting the cut-and-raised portions 52 and 53. As a result, it is possible to suppress the occurrence of interference noise in the cut-and-raised portions 52 and 53 of the fin 43a.

  In addition, since the end 54 of the at least one fin 43a on the centrifugal fan side is inclined downstream in the rotational direction E of the centrifugal fan 61 (that is, in the reverse direction of the fan rear flow), it passes between the fins 43a. By reducing the flow rate of the air flow F1, interference between the fins 43a and the air flow F1 blown out from the centrifugal fan can be weakened. As a result, it is possible to reduce noise generated by interference between the airflow F1 blown out from the centrifugal fan 61 and the fins 43a of the heat exchanger.

  In the indoor unit 31 of the present embodiment, the height H1 from the surface 51a of the main body portion 51 of the fin 43a to the tip of the inclined end portion 54 of the fin 43a is the height H2, H3 of the cut-and-raised portions 52 and 53. Is set to be higher. Therefore, it is possible to more reliably guide the main flow F10 of the airflow F1 so as not to hit the cut and raised portions 52 and 53 by the inclined end portion 54 of the main body portion 51 of the fin 43a.

  Here, as shown in FIG. 8, as a model corresponding to the present embodiment, the airflow V1 emitted from the centrifugal fan 61 in the portion 43d inside the heat exchanger 43 is an angle (elevation angle) with respect to the edge of the fin 43a. Consider a model in which the end portion 54 of the fin 43a is inclined to the downstream side of the airflow V1 when it hits at α degrees. On the other hand, as a model of the comparative example, a model is considered in which the airflow V2 hits the edge of the fin 43a with respect to the heat exchanger 43 at an angle (elevation angle) α degrees from the direction facing the airflow V1. .

  In these two models, the graph of FIG. 9 shows the result of comparing the magnitude of interference noise generated between the airflows V1 and V2 and the end portions 54 of the fins 43a of the heat exchanger 43. The graph in FIG. 9 is a graph showing the noise magnitude β (dBA) for each frequency γ (Hz) of the interference noise, and the curve I is a model corresponding to the present embodiment (a model using the airflow V1 in FIG. 8). ), The curve II shows the experimental results of the model corresponding to the comparative example (model using the airflow V2 in FIG. 8).

  In the graph of FIG. 9, it is experimentally clarified that the curve I has a lower noise level β overall than the curve II, and that the peak at which the noise level β suddenly increases does not occur like the curve II. Has been. From these experimental results, in order to reduce the interference noise between the fin and the airflow, the end 54 of the fin 43a on the centrifugal fan side is located downstream of the airflow F1 blown out from the centrifugal fan 61 (that is, the fan downstream flow). It can be seen that it is preferable to incline toward the back.

(Modification)
In the above embodiment, the end portions 54 on the impeller 23 side of the centrifugal fans 61 of all the fins 43a in the heat exchanger 43 are inclined toward the downstream side of the air flow F1, but the present invention is limited to this. Instead, the end 54 on the impeller 23 side of the centrifugal fan 61 of at least one fin 43a of the fin 43a may be inclined toward the downstream side of the air flow F1.

  For example, in the heat exchanger 43 shown in FIG. 3, the end 54 of the fin 43 a is downstream in the rotational direction of the centrifugal fan 61 in the position P1 closest to the impeller 23 of the centrifugal fan 61 and the downstream range P2. You may make it incline to the side (namely, downstream of the airflow F1 which blows off from the impeller 23 of the centrifugal fan 61).

  In that case, in the heat exchanger 43, in the position closest to the centrifugal fan 61 and in the range downstream thereof, the flow velocity of the airflow is increased, and therefore noise is likely to occur due to interference between the airflow F1 and the fins 43a. Since the end portion 54 of the fin 43a in the range is inclined to the downstream side in the rotation direction of the centrifugal fan 61 (downstream side of the airflow F1 blown out from the centrifugal fan 61), noise due to interference between the airflow and the fins 43a is effective. Can be reduced. In addition, by limiting the portions where the end portions 54 of the fins 43a are inclined, it is possible to suppress a decrease in the flow velocity of the air flow F1 between the fins 43a due to the end portions 54 of the fins 43a inclined at other portions. As a result, it is possible to suppress a decrease in heat exchange capacity.

  Furthermore, as another modification of the present invention, only the end portion 54 of the fin 43a at the position closest to the centrifugal fan 61 in the heat exchanger 43 is disposed downstream of the centrifugal fan 61 in the rotational direction (the airflow blown from the centrifugal fan 61). It may be inclined to the downstream side of F1 and the end portion 54 of the fin 43a at other positions may not be inclined.

  Moreover, in the said embodiment, although demonstrated taking the indoor unit provided with the heat exchanger 43 of 1 row as an example, this invention is not limited to this, This invention is equipped with a heat exchanger of multiple rows. The present invention can also be applied to an indoor unit provided.

  For example, as yet another modification of the present invention, as shown in FIG. 10, a plurality of rows of heat exchangers, that is, the first heat exchanger 43 and the second heat exchanger 63 are moved away from the centrifugal fan 61. Are arranged side by side along (that is, along the flow direction of the air flow F1 blown out from the impeller 23 of the centrifugal fan 61).

  The first heat exchanger 43 in the first row close to the centrifugal fan 61 has the same configuration as the heat exchanger 43 in the first row (see FIGS. 3 to 7), and the end 54 of the fin 43a is The centrifugal fan 61 is inclined toward the downstream side in the rotation direction E (that is, downstream of the airflow F1 blown out from the centrifugal fan 61). The fin 43 a includes a main body portion 51 and a cut-and-raised portion 52 that protrudes from the main body portion 51.

  On the other hand, the second heat exchanger 63 in the second row far from the centrifugal fan 61 is provided with a plurality of fins 63a that are spaced apart from each other and a pipe 63b that connects these fins 63a. The configuration of the heat exchanger 43 is common. In addition, the fin 63 a includes a main body portion 71 and a cut-and-raised portion 72 that protrudes from the main body portion 71. However, the tips 74 of the fins 63a are not inclined with respect to the main body portion 71, and extend parallel to the direction in which the airflow F1 flows.

  In the configuration of the indoor unit shown in FIG. 10, the heat exchangers 43 and 63 are provided in a plurality of rows, and the end portions 54 of the fins 43 a of only the first heat exchanger 43 in the first row close to the centrifugal fan 61 are provided. Since it is inclined, the interference between the fin 43a and the air flow F1 blown out from the centrifugal fan 61 can be weakened, and the noise generated by the interference between the air flow F1 and the fin 43a of the first heat exchanger 43 can be reduced. Is possible.

  In addition, by preventing the tips 74 of the fins 63a of the second heat exchanger 63 in the second row from inclining, the heat exchange capacity can be reduced by inclining the tips 74 of the fins 63a of the second heat exchanger 63. It is possible to suppress. Moreover, since the end portions 54 of the fins 43a of the first heat exchanger 43 in the first row are inclined, the flow velocity of the airflow F1 decreases when the airflow F1 passes between the fins 43a. When the air flow F1 passes between the fins 63a of the second heat exchanger 63 in the second row, the interference between the air flow F1 and the fins 63a is significantly reduced, and the generation of noise due to the interference can be further reduced. It is.

  In addition, in the example shown in FIG. 10, although the example provided with the heat exchangers 43 and 63 of 2 rows is shown, this invention is not limited to this, The heat | fever of multiple rows | lines of 3 or more rows is shown. The structure of an exchanger may be sufficient. Even in that case, it is only necessary to incline the tips of the fins of the heat exchangers in the first row and to incline the tips of the fins of the heat exchangers in the second row and thereafter.

  In the present invention, the shape of the cut and raised portion is not particularly limited, and various shapes can be adopted.

21 blade 23 impeller 31 indoor unit 43 heat exchanger 43a fin 51 main body portion 52, 53 cut-and-raised portion 54 tip portion 61 centrifugal fan 63 second heat exchanger 63a fin F1 airflow

Claims (4)

A centrifugal fan (61) having a plurality of rear-facing blades;
A heat exchanger (43) disposed at a position through which the air flow (F1) blown from the centrifugal fan (61) passes,
The heat exchanger (43) has a plurality of fins (43a) arranged to be spaced apart from each other in a direction orthogonal to the direction in which the rotating shaft (13) of the centrifugal fan (61) extends,
Each of the plurality of fins (43a) has a main body portion (43a) and a cut-and-raised portion (52, 53) cut and raised from the main body portion (51).
The end (54) on the centrifugal fan (61) side of the main body portion (51) of at least one of the fins (43a) is inclined downstream in the rotational direction (E) of the centrifugal fan (61),
The cut and raised portions (52, 53) protrude from the surface (51a) of the main body portion (51) to the side where the end portion (54) is inclined,
Indoor unit (31). In the heat exchanger (43), in the position closest to the centrifugal fan (61) and in the range downstream thereof, the end (54) of the fin (43a) is rotated in the direction of rotation of the centrifugal fan (61) ( E) inclined to the downstream side,
The indoor unit (31) according to claim 1. The height (H1) from the surface (51a) of the main body portion (51) of the fin (43a) to the tip of the end portion (54) of the fin (43a) is the height of the cut and raised portion (52, 53). Set to be higher than the height (H2, H3),
The indoor unit (31) according to claim 1 or 2. A plurality of rows of the heat exchangers (43, 63) are arranged side by side along a direction away from the centrifugal fan (61),
The end (54) of the fin (43a) of only the first row heat exchanger (43) close to the centrifugal fan (61) is inclined,
The indoor unit (31) according to any one of claims 1 to 3.