air conditioner

Abstract

To provide an air conditioner.SOLUTION: Provided is an air conditioner 100 including an indoor unit 10. The indoor unit 10 includes: a casing 50 having an outlet h4; and a cross flow fan 14 arranged inside the casing 50 and having a center shaft C. The casing 50 includes a tongue part 56 having a curved surface 56a of a partial cylinder facing the cross flow fan 14. The casing 50 also includes an edge part 55 positioned at an end part on a side of the outlet h4 of the tongue part 56. The casing 50 further includes a wall part 54 connected to the tongue part 56 at the edge part 55. The curved surface 56a of the partial cylinder corresponds to an arc having a center angle in a range from about 20 to 50 degrees about the center shaft C. The edge part 55 is configured to project toward the cross flow fan 14 from the wall part 54 along the curved surface 56a of the partial cylinder.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to an air conditioner.

Background Art

[0002] Conventionally, in an air conditioner, the annual energy consumption efficiency (APF) has been one of the important indicators, and improvement of the APF of the air conditioner has been continuously demanded. In order to improve the APF, it is important to optimize the configuration of the indoor unit so as to improve the efficiency and reduce the noise. The structure of the indoor unit of a split-type air conditioner usually includes a cross-flow fan disposed in a casing, a heat exchanger also disposed in the casing, and a member constituting the ventilation path of the casing. Improvement of the configuration of these members is considered to contribute to improvement of the efficiency (i.e., APF) of the entire air conditioner and reduction of the noise.

[0003] Related to the improvement of efficiency, Chinese Utility Model Patent No. 209042569 (Patent Document 1) discloses an indoor unit of an air conditioner in which a leading volute tongue is formed on the upper wall of the ventilation path. In Patent Document 1, D0 represents the diameter of the outer edge of the impeller, and assuming that the line segment A i , , ,

[0004] B i represents the vertical distance between the point A on the leading volute tongue and the impeller, it is disclosed that by satisfying 0.035D0 ≦ δ ≦ 0.065D0 and σ < A1B1 for the minimum distance δ between the outer edge of the impeller and the leading volute tongue, the operating efficiency of the cross-flow fan can be improved and the noise can be reduced. In the design of Patent Document 1, the distance A i B i B i gradually decreases as it proceeds to the suction side.

[0004] Further related to efficiency improvements, U.S. Patent Application Publication No. 2005 / 0223732 (Patent Document 2) discloses an air conditioner in which ribs are provided on a stabilizer installed near the air outlet inside the casing so as to be close to the crossflow fan. The ribs of the stabilizer in Patent Document 2 have a gently concave, curved triangular cross-sectional shape on one side facing the crossflow fan, a gently expanding, curved triangular cross-sectional shape, or a flat side facing the crossflow fan that gradually increases in height toward the air outlet, with the corners of the ribs arranged on this air outlet side having rounded triangular cross-sectional shapes.

[0005] However, there remains a need to optimize the design and configuration of the indoor unit of an air conditioner so as to further improve energy efficiency and reduce noise generation. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Chinese Utility Model No. 209042569 [Patent Document 2] US Patent Application Publication No. 2005 / 0223732 Summary of the Invention [Problem to be solved by the invention]

[0007] The present disclosure has been made in consideration of the above points, and aims to provide an air conditioner that reduces air flow resistance and stagnation areas in the ventilation duct by optimizing the design and configuration around the casing tongue (stabilizer) that faces the crossflow fan, thereby improving energy efficiency and reducing noise. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the present disclosure provides an air conditioner having the following features. The air conditioner includes an indoor unit, the indoor unit including a casing with an air outlet, and a crossflow fan disposed within the casing and having a central axis. The casing includes a tongue portion having a curved surface of a partial cylinder facing the crossflow fan. The casing also includes an edge portion located at the end of the tongue on the air outlet side. The casing further includes a wall portion connected to the tongue at the edge portion. The curved surface of the partial cylinder corresponds to an arc having a central angle ranging from approximately 20 degrees to approximately 50 degrees about the central axis. The edge portion is configured to protrude from the wall portion toward the crossflow fan in accordance with the curved surface of the partial cylinder. [Effects of the Invention]

[0009] According to the above configuration, it is possible to optimize the design and configuration around the casing tongue (stabilizer) facing the crossflow fan so as to reduce air flow resistance and stagnation areas in the ventilation duct, thereby improving the energy efficiency of the air conditioner and reducing noise. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a front view of an indoor unit, an outdoor unit, and a remote controller that constitute an air conditioner according to one or more embodiments of the present disclosure. [Figure 2] FIG. 2 is an explanatory diagram showing a refrigerant circuit of an air conditioner according to one or more embodiments of the present disclosure. [Figure 3] FIG. 3 is a cross-sectional side configuration diagram of an indoor unit included in an air conditioner according to the first embodiment of the present disclosure. [Figure 4] FIG. 4 is a diagram showing an enlarged side cross-sectional configuration diagram of the indoor unit of the air conditioner shown in FIG. 3 according to the first embodiment of the present disclosure, together with configuration parameters. [Figure 5] FIG. 5 is a cross-sectional side view of the indoor unit included in an air conditioner according to the second embodiment of the present disclosure. [Figure 6]FIG. 6 is a diagram showing an enlarged side cross-sectional configuration diagram of an indoor unit included in the air conditioner shown in FIG. 5 according to the second embodiment of the present disclosure, together with configuration parameters. [Figure 7] FIG. 7 is a diagram illustrating configuration parameters of the indoor units included in the air conditioner shown in FIG. 5 according to the second embodiment of the present disclosure. [Figure 8] FIG. 8 is a cross-sectional side configuration diagram of an indoor unit included in an air conditioner according to the third embodiment of the present disclosure. [Figure 9] FIG. 9 is a diagram (1 / 2) depicting a series of models for computer simulation in the development of an indoor unit according to one or more embodiments of the present disclosure. [Figure 10] FIG. 10 is a diagram (2 / 2) illustrating a series of models for computer simulation in the development of an indoor unit according to one or more embodiments of the present disclosure. [Figure 11] Figure 11 shows the effect on shaft power (A) and noise (B) for various values ​​of arc angle (θ1) at the same flow rate, as demonstrated by computer simulation. [Figure 12] Figure 12 shows a comparison of velocity contours (distribution) (A, B) and pressure contours (distribution) (C, D) between the baseline model (A, C) shown in Figure 9(A) and the 35-degree arc tongue model (B, D) shown in Figure 9(B), as verified by computer simulation. [Figure 13] Figure 13 shows the effect on shaft power (A) and noise (B) for various values ​​of front nose fillet radius at the same flow rate, as demonstrated by computer simulation. [Figure 14] Figure 14 shows the effect on shaft power (A) and noise (B) for various values ​​of vortex wall angle (θ2) at the same flow rate, as demonstrated by computer simulation. [Figure 15]Figure 15 shows a comparison of static pressure contours between the baseline model (A), which is a 35-degree arc tongue model with a 2 mm radius fillet front nose shown in Figure 9(C), and the 8-degree angle vortex wall model (B), shown in Figure 10(A), as verified by computer simulation. [Figure 16] Figure 16 shows a comparison of velocity contours (A, B) and pressure contours (C, D) between the default back panel model (A, C) shown in Figure 10(A) and the improved back panel model (B, D) shown in Figure 10(B), as verified by computer simulation. [Figure 17] Figure 17 illustrates the locations for measuring the volumetric flow rate around the subcooler heat exchanger in the default back panel model (A) and the improved back panel model (B) for the computer simulation. [Figure 18] Figure 18 shows a comparison of velocity contours (A, B) between the default front panel model (A, C) shown in Figure 10(B) and the improved front panel model (B, D) shown in Figure 10(C), as verified by computer simulation. [Figure 19] Figure 19 shows a comparison of velocity contours (A, B) between the default interior front panel model (A, C) shown in Figure 10(C) and the improved interior front panel model (B, D) shown in Figure 10(D), as verified by computer simulation. DETAILED DESCRIPTION OF THE INVENTION

[0011] One or more embodiments of the present disclosure will be described below with reference to the drawings, but the embodiments of the present disclosure are not limited to the specific embodiments described below. Note that the same reference numerals throughout the drawings indicate the same or corresponding parts.

[0012] The present disclosure relates to an air conditioner (100) including an indoor unit (10). The indoor unit (10) according to an embodiment of the present disclosure includes a casing (50) having an air outlet (h4), and a crossflow fan (14) disposed within the casing (50) and having a central axis (O). The casing (50) includes a tongue (56) having a partially cylindrical curved surface (56a) facing the crossflow fan (14). The casing (50) also includes an edge or front nose (55) located at the end of the tongue (56) on the air outlet (h4) side. The casing (50) further includes a wall or vortex wall (54) connecting to the tongue (56) at the edge (55). In its cross section, the partially cylindrical curved surface (56a) corresponds to an arc having a central angle θ1 ranging from approximately 20 degrees to approximately 50 degrees, centered on the central axis (O). The edge portion (55) is configured to protrude from the wall portion (54) toward the cross-flow fan (14) along a curved surface (56a) of a partial cylinder.

[0013] With this configuration, the airflow from the fan (14) becomes swirling, reducing the resistance of the airflow in the ventilation passage. Furthermore, the design and configuration of the casing tongue (stabilizer) (56) facing the cross-flow fan (14) can be optimized to minimize stagnation areas. This ultimately improves the energy efficiency and reduces noise in the air conditioner (100). In particular, it improves the shaft power of the fan (14) at the same flow rate, thereby reducing noise.

[0014] In a preferred embodiment, the edge 55 has a sharpness equivalent to or greater than that achieved by applying a fillet of a radius of 2 mm or less to the edge 54 formed by the curved surface 56 a of the partial cylinder and the surface 54 a of the wall 54. The larger the fillet radius of the edge 55, the greater the frontal area of ​​the edge 55, which can create a stagnation zone when the flow from the fan 14 strikes the edge 55. For this reason, it is preferable that the edge 55 be as sharp as possible. This edge 55 configuration allows the edge 55 to be as sharp as feasible within design constraints, ensuring a smaller stagnation zone and improving flow rate at the same fan speed.

[0015] In a specific embodiment, the curved surface 56a of the partial cylinder is configured such that, in cross section, an arc originating at the edge 55 is concave toward the suction side S, and each point on the curved surface is equidistant (d1 = d2 = d3) from a corresponding point on the cylindrical surface T described by the blade tips 14a of the crossflow fan 14. The wall 54 is also configured to have a plane U that intersects with the cylindrical surface T described by the blade tips 14a of the crossflow fan 14.

[0016] In one or more preferred embodiments, the casing (50) further comprises: Bottom (59), Top surface (60), a rear wall (52) facing the crossflow fan (14); a bottom wall (53) that is inclined relative to the bottom surface (59), continues to the rear wall (52), and together with the wall portion (54) forms an air passage (h3) to the air outlet (h4); a suction port (h1) opening on the upper surface (60); a rear panel (51) that provides an air passage (h2) from the air intake (h1); an internal front panel (57) that provides an air passage (h2) from the air intake (h1); and An outer front panel (58) that is arranged outside the inner front panel (57) and forms an internal space between the outer front panel (58) and the inner front panel (57). Contains at least one of the following:

[0017] In one or more preferred embodiments, the indoor unit (10) comprises: a filter (15) disposed at the suction port (h1); a heat exchanger (12, 12A, 12B, 12C) disposed in a casing (50); and a subcooler heat exchanger (16) disposed upstream of the heat exchangers (12, 12A) on the rear side within the casing (50) and having a first coil (h) disposed in front of the heat exchangers (12, 12A); Contains at least one of the following:

[0018] In a preferred embodiment, the wall portion (54') has a surface (54a') that is inclined at an angle θ2 ranging from about 3 degrees to about 10 degrees with respect to a plane (V) parallel to the bottom wall (53). This allows the air passage (h3') to the outlet (h4') to expand toward the outside of the casing. This increases the area of ​​the outlet, resulting in a higher flow rate. It also shifts the negative static pressure area in the air passage within the casing (50) downward, which means more pressure recovery. This reduces the shaft power of the fan for the same flow rate, improving noise generation.

[0019] In another preferred embodiment, in the front-to-rear direction, X is the horizontal distance between the center of the first coil (h) of the subcooler heat exchanger (16) and the rear end of the filter (15), and Y is the minimum horizontal gap between the subcooler heat exchanger (16) and the rear panel (51′), and X and Y have the following relationship: 0.5X≦Y≦1.0X This increases the air passage and reduces air resistance, making it possible to reduce the shaft power of the fan for the same flow rate and improve the noise generated.

[0020] In another preferred embodiment, when D is the diameter of the crossflow fan and A is the horizontal length of the intake port (h1′) in the front-to-rear direction, D and A have the following relationship: 1.5D≦A≦1.75D Meet the following.

[0021] In addition, in the front-to-rear direction, the minimum horizontal distance between the heat exchanger and the internal front panel is defined as P, and the length of the filter portion from a first position corresponding to the front end of the heat exchanger at the intake port to a second position corresponding to the internal front panel is defined as Q, and P and Q have the following relationship: 0.5Q≦P≦1.0Q Meet the following.

[0022] The internal front panel includes a first inclined section that slopes from the bottom of the internal front panel away from the heat exchanger, a vertical section that is continuous with the first inclined section and extends upward in a substantially vertical direction, and a second inclined section that is continuous with the vertical section. The second inclined section slopes forward at a predetermined angle θ3 toward the air inlet, where the predetermined angle θ3 satisfies 45 degrees≦θ3<90 degrees relative to the surface of the filter.

[0023] This configuration provides a generally uniformly vertical interior front panel, resulting in an increased intake port (h1). This increased intake port (h1) allows the fan to draw in more air at the same speed. This increases the flow rate at the same fan speed, reducing shaft power. With the reduced shaft power comes reduced noise at the same flow rate.

[0024] In a preferred embodiment, the internal front panel (57'') has a plurality of holes (57f'') that allow air to pass through to the internal space (h5'') formed between the internal front panel (57'') and the external front panel (58''), and the filter (15'') is configured to cover the upper part (h0'') of the internal space (h5'') in addition to the intake port (h1''). This allows the internal space (h5'') formed between the internal front panel (57'') and the external front panel (58'') to be used for air intake. This reduces the shaft power of the fan at the same flow rate, making it possible to improve noise generation.

[0025] (First embodiment) An air conditioner 100 including an indoor unit 10 according to a first embodiment of the present disclosure will be described below with reference to FIGS.

[0026] First, the overall configuration of an air conditioner 100 will be described below with reference to Fig. 1. Fig. 1 is a front view of an indoor unit 10, an outdoor unit 30, and a remote controller 40 that constitute an air conditioner 100 according to one or more embodiments of the present disclosure. The air conditioner 100 is a device that performs air conditioning (hereinafter also referred to as air conditioning) by circulating a refrigerant in a refrigeration cycle (heat pump cycle). As shown in Fig. 1, the air conditioner 100 comprises the indoor unit 10 installed indoors (the space to be air-conditioned), the outdoor unit 30 installed outdoors, and a remote controller 40 that is operated by a user.

[0027] The indoor unit 10 includes a transceiver 10a for communicating with the remote controller 40. The transceiver 10a transmits and receives predetermined signals to and from the remote controller 40 via infrared communication or the like. For example, the transceiver 10a receives signals such as a start command, a stop command, a set temperature command, an operating state change command, and a timer setting command from the remote controller 40. The transceiver 10a also transmits detected values ​​of the indoor temperature and the like to the remote controller 40.

[0028] Although not shown in FIG. 1, the indoor unit 10 and the outdoor unit 30 are connected via refrigerant piping and also via a communication line.

[0029] FIG. 2 is an explanatory diagram showing a refrigerant circuit Q of an air conditioner 100 according to one or more embodiments of the present disclosure. Note that solid arrows in FIG. 2 indicate the flow of refrigerant during heating operation. Also, dashed arrows in FIG. 2 indicate the flow of refrigerant during cooling operation. As shown in FIG. 2, the indoor unit 10 includes an indoor heat exchanger 12 and an indoor fan 14. The indoor unit 10 may further include a sub-cooler heat exchanger 16. The outdoor unit 30 includes a compressor 31, an outdoor heat exchanger 32, an outdoor fan 33, an outdoor expansion valve 34, and a four-way valve 35.

[0030] The indoor heat exchanger 12 is a heat exchanger that exchanges heat between the refrigerant flowing through the heat transfer tube and the indoor air. The indoor fan 14 is a cylindrical crossflow fan 14 and is driven by an indoor fan motor. The subcooler heat exchanger 16 is connected to the refrigerant piping between the indoor heat exchanger 12 and the compressor suction section.

[0031] The compressor 31 is a device that compresses a low-temperature, low-pressure gas refrigerant by driving a compressor motor 31a and discharges it as a high-temperature, high-pressure gas refrigerant. The outdoor heat exchanger 32 is a heat exchanger that exchanges heat between the refrigerant flowing through its heat transfer tube and the outside air sent in by the outdoor fan 33.

[0032] The outdoor fan 33 is a fan that sends outside air to the outdoor heat exchanger 32 by being driven by an outdoor fan motor 33a, and is installed near the outdoor heat exchanger 32. The outdoor expansion valve 34 has the function of decompressing the refrigerant condensed in the "condenser" (one of the outdoor heat exchanger 32 and the indoor heat exchanger 12). The refrigerant decompressed in the outdoor expansion valve 34 is led to the "evaporator" (the other of the outdoor heat exchanger 32 and the indoor heat exchanger 12).

[0033] The four-way valve 35 is a valve that switches the refrigerant flow path depending on the operating state of the air conditioner 100. That is, during cooling operation (see the dashed arrow), the refrigerant circulates in a refrigeration cycle in a refrigeration circuit Q that is formed by sequentially connecting a compressor 31, an outdoor heat exchanger 32 (condenser), an outdoor expansion valve 34, and an indoor heat exchanger 12 (evaporator) in a ring shape via the four-way valve 35.

[0034] Also, during heating operation (see solid arrow), refrigerant circulates in a refrigeration cycle in a refrigerant circuit Q, which is made up of a compressor 31, an indoor heat exchanger 12 (condenser), an outdoor expansion valve 34, and an outdoor heat exchanger 32 (evaporator) connected in a circular sequence via a four-way valve 35.

[0035] That is, in the refrigerant circuit Q in which the refrigerant circulates in a refrigeration cycle through the compressor 31, the "condenser", the outdoor expansion valve 34 and the "evaporator" in that order, one of the "condenser" and the "evaporator" is the outdoor heat exchanger 32, and the other is the indoor heat exchanger 12.

[0036] Fig. 3 is a diagram showing a side cross-sectional configuration of the indoor unit 10 included in the air conditioner 100 according to the first embodiment of the present disclosure. As shown in Fig. 3, the indoor unit 10 includes an indoor heat exchanger 12, a crossflow fan 14, a filter 15, upper and lower airflow direction vanes 19, left and right airflow direction vanes (not shown), and a casing 50.

[0037] The indoor heat exchanger 12 is disposed within the casing 50. The indoor heat exchanger 12 has a plurality of fins and a coil (heat transfer tube) g that penetrates the fins. The indoor heat exchanger 12 is divided into three parts: a rear indoor heat exchanger 12A, a middle indoor heat exchanger 12B, and a front indoor heat exchanger 12C. The front indoor heat exchanger 12C is disposed below and in front of the crossflow fan 14. The middle indoor heat exchanger 12B is disposed above and in front of the crossflow fan 14. The rear indoor heat exchanger 12A is disposed above and behind the crossflow fan 14. The upper end of the front indoor heat exchanger 12C is connected to the lower end of the middle indoor heat exchanger 12B. The upper end of the middle indoor heat exchanger 12B is connected to the upper end of the rear indoor heat exchanger 12A.

[0038] 3, a subcooler heat exchanger 16 is further disposed on the rear side within the casing 50, upstream of the indoor heat exchanger 12. The subcooler heat exchanger 16 has a coil (heat transfer tube). The subcooler heat exchanger 16 assists the indoor heat exchanger 12.

[0039] The crossflow fan 14 is disposed within the casing 50, near the indoor heat exchanger 12. The crossflow fan 14 is composed of multiple fan blades, a partition plate on which these fan blades are mounted, and an indoor fan motor that serves as a drive source. The crossflow fan 14 has a central axis O around which it rotates.

[0040] The casing 50 is configured to include a back panel or housing base (51, 52, 53) on which devices such as the indoor heat exchanger 12 and the crossflow fan 14 are installed, an internal front panel 57, and an external front panel 58. An air intake port h1 opens in the top surface 60 of the casing 50. An air outlet port h4 opens on the front side of the bottom surface 59 of the casing 50. The external front panel 58 is a panel installed to cover the front side of the air conditioner 100 and is rotatable forward around its upper end as an axis. The external front panel 58 is positioned outside the internal front panel 57.

[0041] Indoor air is taken into the indoor unit 10 through an air inlet port h1 that opens to the top surface 60 of the casing 50. A filter 15 is installed at the air inlet port h1 above the indoor heat exchanger 12, and removes dust from the air passing through the air inlet port h1.

[0042] The rear panel includes a rear upper wall 51, a rear wall (scroll portion) 52, and a bottom wall 53. The rear upper wall 51 is located on the suction side, rearward of the rear indoor heat exchanger 12A and the subcooler heat exchanger 16. The rear wall 52 is located on the outlet side and provides a curved surface facing the crossflow fan 14. The bottom wall 53 is inclined with respect to the bottom surface 59 of the casing 50 and is continuous with the rear wall 52. In the embodiment shown in FIG. 3 , a rear tongue 52a facing the crossflow fan 14 is provided above the rear wall 52 on the suction side. The rear upper wall 51 and the internal front panel 57 provide an air passage h2 from the air inlet h1. The rear wall 52 and the bottom wall 53 provide an air passage h3 to the air outlet h4. From the rear tongue 52a facing the cross-flow fan 14, the rear wall 52 and the bottom wall 53 act as rear guide plates that guide the air and stabilize the air flow.

[0043] The air outlet h4 side of the unit is configured to include a casing 50, a front tongue (or stabilizer) 56 facing the crossflow fan 14, an edge (or front nose) 55 located at the end of the front tongue 56 on the air outlet h4 side, and a vortex wall 54 connected to the front tongue 56 at the edge 55. The vortex wall 54, together with the rear wall 52 and the opposing bottom wall 53, forms an air passage h3 to the air outlet h4. The vortex wall 54, which is the inner wall surface of the air passage h3 extending from the front tongue 56 facing the crossflow fan 14 to the back side of the drain pan, functions as a front guide plate that guides air and stabilizes the air flow.

[0044] The vertical air deflector 19 is a plate-like member that adjusts the vertical flow of air blown into the room as the crossflow fan 14 rotates. The vertical air deflector 19 is disposed near the air outlet h4 and is rotated vertically by a vertical air deflector motor. The vertical air deflector 19 is also controlled to open and close the air outlet h4. In addition, left and right air deflectors (not shown) are typically disposed in the outlet-side ventilation duct h3 and adjust the left and right flow of air blown into the room as the crossflow fan 141 rotates.

[0045] Air drawn in through the air intake port h1 passes through the intake-side ventilation passage h2 and exchanges heat with the refrigerant flowing through the coils (heat transfer tubes) of the indoor heat exchangers 12A-12C. The heat-exchanged air is then guided to the outlet-side ventilation passage h3. The rear wall 52 has a curved surface that bulges outward in the radial direction of the crossflow fan 14 and extends, together with the bottom wall 53, to the air outlet h4, thereby guiding the heat-exchanged air. The air flowing through the outlet-side ventilation passage h3 is guided in a predetermined direction by the left-right air deflectors and the up-down air deflectors 19 and is then blown out into the room through the air outlet h4. The rear guide plate (rear tongue 52a, rear wall 52, bottom wall 53) and the front guide plate (front tongue 56, edge portion 55, vortex wall portion 54) form an air flow generated by the rotation of the crossflow fan 14.

[0046] Figure 4 is a diagram showing an enlarged view of the side cross-sectional configuration diagram shown in Figure 3 of the indoor unit 10 included in the air conditioner 100 according to the first embodiment of the present disclosure, along with configuration (design) parameters. Figure 4(A) is an enlarged view showing portions of the casing 50 around the front tongue 56, edge portion 55, vortex wall portion 54, and bottom wall 53 in the side cross-sectional configuration diagram shown in Figure 3, as well as a portion near the front tongue 56 of the cross-flow fan 14. Figure 4(B) is a further enlarged view showing portions of the casing 50 centered around the front tongue 56 and edge portion 55 and a portion near the front tongue 56 of the cross-flow fan 14 in the enlarged view of the side cross-sectional configuration diagram shown in Figure 4(A).

[0047] As shown in FIG. 4A, the front tongue 56 has a curved surface 56a facing the crossflow fan 14. The curved surface 56a according to the embodiment of the present disclosure is a partial cylindrical surface that corresponds to an arc having a predetermined central angle (arc angle) θ1 centered on the central axis C of the crossflow fan 14 in its cross section. FIG. 4A also shows the cylindrical surface T (circle in cross section) described by the blade tips 14a of the crossflow fan 14. The partial cylindrical curved surface 56a of the front tongue 56 is configured such that, in its cross section, the arc is concave from the edge portion 55 toward the suction side S, and each point on the curved surface 56a is equidistant (d1 = d2 = d3) from a corresponding point on the cylindrical surface T described by the blade tips 14a of the crossflow fan 14. The front tongue 56 extends from the edge portion 55, which is the closest point on the discharge side, toward the suction side, and is configured to cover the partial cylinder of the crossflow fan 14 at the predetermined angle.

[0048] The central angle θ1 of the arc defining the curved surface 56a of the partial cylinder is preferably in the range of about 20 degrees to about 50 degrees, more preferably in the range of about 25 degrees to about 45 degrees, and even more preferably in the range of about 30 degrees to about 40 degrees.

[0049] 4(A) and 4(B), edge portion 55, which is the blowing-side end portion of front tongue portion 56, is configured to protrude from vortex wall portion 54 toward crossflow fan 14 along partially cylindrical curved surface 56a, thereby forming a sharp edge shape. In the embodiment being described, vortex wall portion 54 is configured to have an (imaginary) plane (line in cross section) U that intersects (i.e., is not tangent to) the cylindrical surface (circle in cross section) T described by blade tips 14a of crossflow fan 14.

[0050] In FIG. 4B, E represents the ideal edge between the curved surface 56a and the surface 54a. It is preferable for the edge 55 to be as sharp as possible. However, due to manufacturing constraints, a certain degree of roundness is required. Therefore, in a preferred embodiment, in order to achieve both improved performance (improved energy efficiency and reduced noise) and manufacturing constraints, the edge 55 has a sharpness equivalent to or sharper than that obtained by applying a fillet of a predetermined radius to the ideal edge E formed by the partially cylindrical curved surface 56a and the surface 54a of the vortex wall 54. F1 to F3 in FIG. 4B represent multiple edge surfaces 55a to which fillets of various radii have been applied. In a preferred embodiment, the edge 55 has a sharpness equivalent to or sharper than that obtained by applying a fillet of a radius of 4 mm or less to the edge E, and more preferably, a sharpness equivalent to or sharper than that obtained by applying a fillet of a radius of 2 mm or less.

[0051] The configuration of the front tongue 56 with the partially cylindrical curved surface 56a and the sharp edge 55 described above causes the airflow ejected from the crossflow fan 14 to swirl, reducing airflow resistance in the ventilation duct and optimizing the configuration of the casing 50 to minimize stagnation areas. This in turn improves the energy efficiency of the air conditioner 100 and reduces noise. As will be discussed later, the shaft power of the crossflow fan 14 at the same flow rate is improved, and noise generation is reduced.

[0052] The larger the fillet radius of the edge 55, the greater the frontal area of ​​the edge 55 that can create a stagnation area when the flow from the crossflow fan 14 strikes the edge 55. For this reason, it is preferable to make it as sharp as possible. The sharp filleted edge 55 configuration allows the edge to be as sharp as feasible within design constraints, ensuring a smaller stagnation area and improving flow rate at the same fan speed, as discussed below.

[0053] (Second embodiment) Hereinafter, with reference to Figs. 5 to 7, an air conditioner 100 including an indoor unit 10 according to a second embodiment of the present disclosure, which is capable of further improving the energy efficiency of the air conditioner 100 and further reducing noise, will be described.

[0054] FIG. 5 is a side cross-sectional configuration diagram of an indoor unit 10 provided in an air conditioner 100 according to a second embodiment of the present disclosure. As shown in FIG. 5, the indoor unit 10 according to the second embodiment of the present disclosure, like the first embodiment shown in FIG. 3, includes an indoor heat exchanger 12, a crossflow fan 14, a filter 15, upper and lower airflow direction vanes 19, left and right airflow direction vanes (not shown), and a casing 50. Note that the second embodiment is similar to the first embodiment in many respects, and therefore the following description will focus on the differences. Note also that differences from the first embodiment will be referred to using reference numerals with a single prime (') added.

[0055] In the second embodiment shown in FIG. 5, the shape of the rear upper wall 51' of the rear panel located on the suction side behind the rear indoor heat exchanger 12A and the subcooler heat exchanger 16 is modified compared to the first embodiment shown in FIG. 3. The shape of the inner front panel 57' located inside the outer front panel 58 is also modified. These modifications also affect the upper surface 60' of the casing 50, the air intake port h1' opening in the upper surface 60', the filter 15' provided at the air intake port h1', and the air passage h2' provided by the rear upper wall 51' and the inner front panel 57'. In the second embodiment shown in FIG. 5, the shape of the vortex wall portion 54' connecting to the front tongue portion 56 at the edge portion 55 is modified compared to the embodiment shown in FIG. 3, in relation to the air outlet h4. The shape of the air passage h3' provided by the vortex wall portion 54' and the opposing bottom wall 53 and rear wall 52, and the air outlet h4' therefor, are also modified.

[0056] FIG. 6 is a diagram showing an enlarged side cross-sectional configuration diagram of the indoor unit 10 provided in the air conditioner 100 shown in FIG. 5 according to the second embodiment of the present disclosure, together with configuration (design) parameters.

[0057] First, the change in the shape of the vortex wall portion 54' will be described with reference to Figure 6(A). Figure 6(A) is an enlarged view showing the front tongue portion 56, edge portion 55, vortex wall portion 54', bottom wall 53, and the area near the front tongue portion 56 of the crossflow fan 14 in the side cross-sectional configuration diagram shown in Figure 5. Figure 6(A) shows the surface W of the bottom wall 53, a (virtual) plane V parallel to the surface W, and a (virtual) plane U of the vortex wall portion 54' that is inclined at a predetermined angle relative to plane V. Figure 6(A) also shows the center Z on the edge portion 55 that rotates the plane U of the vortex wall portion 54' relative to plane V.

[0058] In the second embodiment, as shown in FIG. 6A, the vortex wall portion 54' has a surface 54a' corresponding to a plane U inclined at a predetermined angle θ2 with respect to a plane V parallel to the surface W of the bottom wall 53. This allows the air passage h3' to the air outlet h4 to expand toward the outside of the casing 50. The predetermined angle θ2 is preferably in the range of approximately 3 to 10 degrees, more preferably in the range of approximately 5 to 9 degrees. As shown in FIG. 6A, the plane U of the vortex wall portion 54' is inclined so that the plane U rotates from the plane V around the center Z on the edge portion 55. A drain pan or the like is disposed behind the vortex wall portion 54', but design constraints impose a feasible upper limit on the angle θ2. By setting the angle θ2 to approximately 3 to 10 degrees, the vortex wall portion 54' can be inclined to the maximum extent possible within the feasible range that satisfies the design constraints, thereby enlarging the air outlet 4h. In addition, even in the second embodiment, the vortex wall portion 54' is configured to have a (virtual) plane (line in cross section) U that intersects (i.e., is not tangent to) the cylindrical surface (circle in cross section) T described by the blade tip 14a of the cross-flow fan 14.

[0059] By changing the shape of the vortex wall portion 54', the area of ​​the air outlet h4' is increased, resulting in a higher flow rate. As will be discussed later, the negative static pressure area in the air passage inside the casing 50 is shifted downward, meaning that pressure recovery is increased. This allows for a reduction in the shaft power of the fan at the same flow rate, improving noise generation.

[0060] Next, a change in the shape of the rear upper wall 51' of the rear panel will be described with reference to FIG. 6(B). FIG. 6(B) is an enlarged view showing the upper portion of the rear upper wall 51' of the rear panel, the subcooler heat exchanger 16, the rear indoor heat exchanger 12A, and the crossflow fan 14 in the side cross-sectional configuration diagram shown in FIG. 5. FIG. 6(B) shows two configuration parameters X and Y. The subcooler heat exchanger 16 includes coils, and the coil located most forward will be referred to as the first coil h.

[0061] In the second embodiment, X is the horizontal distance in the front-to-rear direction between the center of the first coil h of the subcooler heat exchanger 16 and the rear end of the filter 15, and Y is the minimum horizontal gap in the front-to-rear direction between the subcooler heat exchanger 16 and the rear upper wall 51′ of the rear panel, and X and Y have the following relationship: 0.5X≦Y≦1.0X The shape of the rear upper wall 51' of the rear panel is changed so as to satisfy the following.

[0062] This change in the shape of the rear upper wall 51' of the rear panel increases the air passage and reduces air resistance, making it possible to reduce the shaft power of the fan for the same flow rate and improve the noise generated.

[0063] Next, changes to the shape of the internal front panel 57' will be described with reference to Fig. 7. Fig. 7 is a diagram illustrating the configuration parameters of the indoor unit 10 provided in the air conditioner 100 shown in Fig. 5 according to the second embodiment of the present disclosure. Fig. 7 shows five configuration parameters D, A, P, Q, and θ3.

[0064] The internal front panel 57' according to the second embodiment includes a first inclined section 57a' that slopes from the bottom of the internal front panel 57' away from the indoor heat exchanger (front indoor heat exchanger 12C). The internal front panel 57' also includes vertical sections 57b' and 57c' that are continuous with the first inclined section 57a' and extend upward in a substantially vertical direction. The internal front panel 57' further includes a second inclined section 57d' that is continuous with the vertical sections 57b' and 57c'. The second inclined section 57d' constitutes the air intake port h1'. In the embodiment shown in FIG. 7, the upwardly extending vertical sections include the first vertical section 57b' and a second vertical section 57c' that is recessed rearward from the surface of the first vertical section 57b'.

[0065] In the second embodiment, when D is the diameter of the cross-flow fan 14 and A is the horizontal length in the front-to-rear direction of the air intake port h1′ defined by the shape of the inner front panel 57′ (particularly the characteristics of the second inclined section 57d′), the parameters D and A satisfy the following relationship: 1.5D≦A≦1.75D The shape of the inner front panel 57' is modified to satisfy the following:

[0066] In the second embodiment, P is the minimum horizontal distance between the indoor heat exchanger 12 and the internal front panel 57′ in the front-rear direction, and Q is the length of the filter 15′ in the front-rear direction from a first position corresponding to the front end 12e of the indoor heat exchanger 12 at the air inlet h1′ to a second position corresponding to the internal front panel 57′, and the parameters P and Q satisfy the following relationship: 0.5Q≦P≦1.0Q The shape of the inner front panel 57' is modified to satisfy the following:

[0067] The second inclined section 57d' is inclined upward at a predetermined angle θ3 toward the air inlet h1. Here, the predetermined angle θ3 is an angle relative to the surface of the filter 15' and is expressed as follows: 45 degrees≦θ3<90 degrees It is preferable that the following is satisfied.

[0068] Providing a substantially uniformly vertical interior front panel 57' results in an increased air inlet h1'. This increased air inlet h1' allows the fan to draw in more air at the same speed. This increases the flow rate at the same fan speed, reducing shaft power. With reduced shaft power comes reduced noise at the same flow rate.

[0069] (Third embodiment) Hereinafter, an air conditioner 100 including an indoor unit 10 according to a third embodiment of the present disclosure will be described with reference to FIG.

[0070] Figure 8 is a side cross-sectional configuration diagram of an indoor unit 10 provided in an air conditioner 100 according to a third embodiment of the present disclosure. Note that the third embodiment is similar in many respects to the second embodiment, and therefore the following description will focus on the differences. Please note that differences from the second embodiment will be referred to using reference numerals with two primes ('').

[0071] In the third embodiment shown in FIG. 8, the shape of the inner front panel 57″ is further modified compared to the second embodiment shown in FIG. 5. In the third embodiment, the inner front panel 57″ is perforated to have a plurality of holes 57f″ that allow air to pass through to the inner space h5″ formed between the inner front panel 57″ and the outer front panel 58″. The perforations may be circular holes, rectangular holes, or any openings. With this modification, the filter 15″ is further configured to cover an upper portion h0″ of the inner space h5″ in addition to the air inlet h1″.

[0072] By drilling a hole in the inner front panel 57' and covering the upper part h0'' of the inner space h5'' between the inner front panel 57' and the outer front panel (58'') with a filter 15'', the inner space h5'' can be used for air intake. This reduces the shaft power of the fan at the same flow rate and improves the noise generated.

[0073] (Computer simulation study) The features of the indoor unit 10 of the air conditioner 100 in one or more embodiments have been described above with reference to Figures 1 to 8. Below, the performance characteristics of the indoor unit 10 of the air conditioner 100 in one or more embodiments shown in Figures 1 to 8 will be described with reference to Figures 9 to 19.

[0074] 9 and 10 depict a series of models used in computer simulations during the development of an indoor unit 10 according to one or more embodiments of the present disclosure. FIG. 9(A) shows a baseline model, which includes a flat, L-shaped front tongue 56 rather than the partially cylindrical front tongue 56 according to embodiments of the present disclosure. FIG. 9(B) shows a model (35-degree arc tongue model) that includes a partially cylindrical front tongue 56a with a central angle θ1 of 35 degrees, an edge (or front nose) 55 with an ideal sharp edge E, and a vortex wall 54 parallel to the bottom wall 53. FIG. 9(C) shows a model (+2mm fillet front nose model) in which a 2mm radius fillet is applied to the edge 55 of the model shown in FIG. 9(B).

[0075] Figure 10(A) shows a model (+8-degree vortex wall model) in which the vortex wall 54 of the model shown in Figure 9(C) is inclined to have a plane U at an angle θ2 of 8 degrees with respect to a plane V parallel to the surface W of the bottom wall 53. Figure 10(B) shows a model (+improved rear panel model) in which the rear panel (upper rear wall 51) of the model shown in Figure 10(A) is modified so that the configuration parameters X and Y in Figure 6(B) satisfy the above relationship. Figure 10(C) shows a model (+improved front panel model) in which the internal front panel 57 of the model shown in Figure 10(B) has been improved to have a flat vertical surface so that the five configuration parameters D, A, P, Q, and θ3 shown in Figure 7 satisfy the above relationship. Figure 10(D) shows a model (+improved internal front panel model) in which the internal front panel of the model shown in Figure 10(C) has been improved by providing holes in it.

[0076] Figure 11 shows the effects of various values ​​of the arc angle (θ1) on shaft power (A) and noise (B) at the same flow rate, as demonstrated by computer simulation. The effect of the arc angle θ1 of the front tongue 56 was simulated. To determine the optimal arc angle θ1, analysis was performed for central angles θ1 from 20 to 60 degrees in 5-degree increments. The baseline for this simulation was the baseline model shown in Figure 9(A). As shown in Figure 11(A), shaft power is reduced for central angles θ1 up to 55 degrees, with the greatest improvement at 35 degrees. As shown in Figure 11(B), noise is reduced for central angles θ1 up to 55 degrees, with the greatest improvement at 40 degrees. This is because, above 35 degrees, the flow from the right side of the indoor heat exchanger 12 begins to be blocked, leading to a decrease in performance.

[0077] Table 1 shows the shaft power and noise at various values ​​of the arc central angle θ1 at the same rotation speed, along with the flow rate. Table 2 shows the shaft power and noise at various values ​​of the arc central angle θ1 at the same flow rate, along with the change in rotation speed.

[0078] [Table 1]

[0079] [Table 2]

[0080] Figure 12 shows a comparison of the velocity contours (distribution) (A, B) and static pressure contours (distribution) (C, D) between the baseline model (A, C) shown in Figure 9(A) and the 35-degree arc tongue model (B, D) shown in Figure 9(B), as verified by computer simulation. The 35-degree arc tongue model reduces the distance between the edge 55 and the blade tip 14a of the crossflow fan 14 compared to the baseline model, thereby reducing the amount of backflow toward the suction side. The flow is also uniformly smooth between the blade and the arc-shaped tongue due to the ideal arc shape of the forward tongue 56. The 35-degree arc tongue model also increases the size of the eccentric vortex compared to the baseline model. The 35-degree arc tongue model exhibits optimal improvements of 9.1% shaft power reduction and 2.7 dB noise reduction compared to the baseline model shown in Figure 9(A).

[0081] Figure 13 shows the effects of various values ​​of fillet radius of the edge 55 on shaft power (A) and noise (B) at the same flow rate, as verified by computer simulation. The baseline for this simulation is the 35-degree arc tongue model shown in Figure 9(B). The effect of edge 55 sharpness was investigated based on the model with the optimized 35-degree arc angle described above. Due to manufacturing considerations, a fillet must be applied to the edge 55. Therefore, fillets with radii ranging from 1 mm to 5 mm were applied in stages, as shown in Figure 4(B), and the effects on shaft power and noise were investigated. As shown in Figures 13(A) and 13(B), shaft power increased with increasing fillet radius. This is because the frontal area of ​​the edge 55 increases as the fillet radius of the edge 55 increases, resulting in a larger stagnation area. This stagnation area is created when the flow from the crossflow fan 14 strikes the edge 55. A larger stagnation area reduces the flow rate. Considering the minimum requirements, a 2 mm radius fillet is optimal, which results in a 1.9% increase in shaft power and a 0.2 dB noise improvement.

[0082] Table 3 shows the shaft power and noise with various values ​​of fillet radius at the same rotation speed, along with the flow rate. Table 4 shows the shaft power and noise with various values ​​of fillet radius at the same flow rate, along with the change in rotation speed.

[0083] [Table 3]

[0084] [Table 4]

[0085] Figure 14 shows the effects of various values ​​of the vortex wall inclination angle θ2 on shaft power (A) and noise (B) at the same flow rate, as demonstrated by computer simulation. The effect of the inclination angle θ2 of the vortex wall 54 relative to the plane V parallel to the surface W of the bottom wall 53 was simulated. The baseline for this simulation was a 35° arc tongue model (+2 mm fillet front nose model) with a 2 mm radius filleted edge, as shown in Figure 9(C). The plane U of the vortex wall 54 was rotated counterclockwise around the center Z, as shown in Figure 6(B), in 1-degree increments. In addition to the baseline, Figure 10 also includes 10 cases with inclination angles θ2 ranging from 3 to 12 degrees. As shown in Figures 14(A) and 14(B), shaft power and noise improve as the inclination angle θ2 of the vortex wall 54 increases. This is because the larger the angle of the vortex wall portion 54, the larger the air outlet h4 becomes, which in turn results in a higher flow rate.

[0086] Figure 15 shows a comparison of static pressure contours between the baseline model (A), the +2 mm fillet front nose model shown in Figure 9(C), and the +8° vortex wall model (B), shown in Figure 10(A), as verified by computer simulation. As shown in Figures 15(A) and 15(B), the negative static pressure region (black area) shifts downward, indicating a greater pressure recovery in the +8° vortex wall model compared to the baseline 0° case. The slope of the improvement decreases above 7°. Considering the feasible range, an 8° angle appears optimal, providing a 12.3% shaft power improvement and a 1.6 dB improvement. This improvement is possible when the bottom vertical deflector 19 is continuous with the bottom wall 53.

[0087] Table 5 shows the shaft power and noise with flow rate for various values ​​of vortex wall angle at the same rotation speed. Table 6 shows the shaft power and noise with flow rate for various values ​​of vortex wall angle at the same flow rate, with change in rotation speed.

[0088] [Table 5]

[0089] [Table 6]

[0090] Figure 16 shows a comparison of velocity contours (A, B) and pressure contours (C, D) between the default rear panel model (+8° vortex wall model) (A, C) shown in Figure 10(A) and the improved rear panel model (B, D) shown in Figure 10(B), as verified by computer simulation. The improved rear panel model shown in Figure 10(B) is a modified version of the rear panel (rear upper wall 51) of the model shown in Figure 10(A) in which the minimum horizontal gap Y between the subcooler heat exchanger 16 and the rear panel (rear upper wall 51') is increased by 9.6 mm from the default value. In the improved rear panel model, parameter Y satisfies the relationship with parameter X in Figure 6(B). This change increases the airflow path and reduces air resistance.

[0091] The velocity contours in Figures 16(A) and 16(B) show that the narrow airflow path of the default rear panel results in higher velocities, while the increased gap Y of the improved rear panel model results in lower velocities. Figure 17 shows the locations p, q, and r at which the volumetric flow rates around the subcooler heat exchanger 16 are measured for the default rear panel model (A) and the improved rear panel model (B) for computer simulations. The volumetric flow rate at the location indicated by line q for the improved rear panel model (B) is 1.97 times higher than for the default rear panel model (A). The pressure contours in Figures 16(C) and 16(D) also show that the pressure distribution improves with increasing the gap. The pressure loss across lines p and r for the improved rear panel model (B) is estimated to be 12% lower than for the default rear panel model (A). This indicates that the air resistance in this region is reduced, resulting in an increased flow rate at the same fan speed.

[0092] Table 7 shows the shaft power and noise for the default rear panel model and the improved rear panel model at the same rotation speed and flow rate. Table 7 shows that the improvement of the rear panel reduces the shaft power and noise by 8.07m 3 At the same flow rate of / min, the shaft power was reduced by 4.4% and the noise was reduced by 0.4db.

[0093] [Table 7]

[0094] Figure 18 shows a comparison of velocity contours (A, B) between the default front panel model (A, C) shown in Figure 10(B) and the improved front panel model (B, D) shown in Figure 10(C), as verified by computer simulation. The improved front panel model in Figure 10(C) has been improved to have a flat vertical inner front panel, which increases the length A of the air inlet h1 by 11.7%. Furthermore, the wider air inlet h1 increases Q by approximately the same amount, and the change to a nearly vertical inner front panel reduces P by 26.7%.

[0095] When measuring the volumetric flow rate, the default internal front panel is 10.04 m 3 / min, and in the case of the improved front panel, it is 10.32m 3 / min. From the velocity contours shown in Figure 18, it can be seen that the improved inner front panel makes the flow in this area uniform. This increases the flow rate at the same fan speed, and the shaft power is 8.07 m 3 / min, which is a 4.9% reduction compared to the default front panel. The reduction in shaft power also resulted in a 1 dB noise reduction at the same flow rate. Table 8 shows the shaft power and noise for the default front panel model and the improved front panel model at the same rotation speed and flow rate.

[0096] [Table 8]

[0097] Figure 19 shows a comparison of velocity contours (A, B) between the default interior front panel model (+ modified front panel model) (A, C) shown in Figure 10(C) and the perforated modified interior front panel model (B, D) shown in Figure 10(D), as verified by computer simulation. In the model shown in Figure 10(D), the interior front panel has rectangular slots perforated along the length of the indoor unit, increasing the suction area and allowing more air to be drawn in by the fan at the same speed. By providing gaps (extending the filter section) at the top of these interior and exterior front panels and by perforating the interior front panels, the air suction area increases. Increasing the indoor unit's air suction area allows more air to be delivered at the same fan speed. Table 9 shows the shaft power and noise for the default interior front panel model and the perforated modified interior front panel model at the same rotation speed and flow rate.

[0098] [Table 9]

[0099] The velocity contours shown in Figures 19(A) and 19(B) show that the space between the inner and outer front panels is used for suction. 3 / mm, the shaft power is reduced by 3.7% and the noise is reduced by 0.6dB.

[0100] Overall, the improved (perforated) internal front panel model shown in Figure 10(D) can reduce shaft power by 25% and noise by 6.4 dB compared to the initial baseline model shown in Figure 9(A) at the same flow rate.

[0101] As described above, according to the embodiments of the present disclosure, it is possible to optimize the design and configuration around the casing tongue (stabilizer) facing the crossflow fan so as to reduce air flow resistance and stagnation areas in the ventilation duct of the indoor unit, thereby making it possible to provide an air conditioner with improved energy efficiency and reduced noise.

[0102] For the same fan speed, the flow rate increases and the noise level decreases. Also, for the same flow rate, the shaft power, the relative speed around the fan, the noise level, and the fan speed decrease. Overall, this contributes to an improvement in the annual performance factor (APF) rating of the air conditioner.

[0103] It should be noted that the embodiments of the present invention are not limited to the above-described embodiments and may include various modifications. For example, the above-described embodiments have been described in detail for ease of understanding, and are not necessarily limited to those including all of the described features. Furthermore, some of the features of one embodiment may be replaced with features of another embodiment, or features of one embodiment may be added to features of another embodiment. Furthermore, some of the features of each embodiment may be added to, deleted from, or replaced with other features. [Explanation of symbols]

[0104] 100...air conditioner, 10...indoor unit, 12...indoor heat exchanger, 14...crossflow fan, 15...filter, 16...subcooler heat exchanger, 19...upper and lower air deflectors, 30...outdoor unit, 31...compressor, 32...outdoor heat exchanger, 33...outdoor fan, 34...outdoor expansion valve, 35...four-way valve, 40...remote controller, 50...casing, 51...rear upper wall, 52...rear wall, 53...bottom wall, 54...vortex wall portion, 55...edge portion, 56...front tongue portion, 57...inner front panel, 58...outer front panel, 59...bottom surface, 60...top surface, h1...air intake port, h2, h3...ventilation channel, h4...air outlet port, h5...space, h0...upper portion of space

Claims

1. An air conditioner including an indoor unit, the indoor unit comprising: a casing having an air outlet; a cross-flow fan disposed within the casing and having a central axis; The casing comprises: a tongue portion having a partially cylindrical curved surface facing the cross flow fan; an edge portion located at an end portion of the tongue portion on the side of the air outlet; a wall portion connecting to the tongue portion at the edge portion; The curved surface of the partial cylinder has a central angle θ ranging from 20 degrees to 50 degrees about the central axis. １ and the edge portion is configured to protrude from the wall portion toward the cross flow fan according to the curved surface of the partial cylinder, and the casing further has: The top surface and a suction port opening on the upper surface; an interior front panel that provides a ventilation path from the intake; an outer front panel that is disposed outside the inner front panel and forms an internal space between the outer front panel and the inner front panel; The indoor unit further comprises: A filter disposed at the intake port Including, An air conditioner wherein the interior front panel has a plurality of holes that allow air to pass through to the interior space, and the filter is configured to cover the air inlet as well as an upper portion of the interior space.

2. The casing further comprises: The bottom and a rear wall facing the crossflow fan; a bottom wall that is inclined relative to the bottom surface, is continuous with the rear wall, and forms an air passage to the air outlet together with the wall portion; and the wall is at an angle θ ranging from 3 to 10 degrees with respect to a plane parallel to the bottom wall. ２ 2. The air conditioner according to claim 1, wherein the casing has a surface that slopes in a direction perpendicular to the casing, and the air passage to the air outlet widens as it approaches the outside of the casing.

3. 2. The air conditioner of claim 1, wherein the curved surface of the partial cylinder is configured such that the arc starts at the edge portion and is concave toward the suction side, and each point on the curved surface is equidistant from a corresponding point on the cylindrical surface described by the blade tips of the crossflow fan, and the wall portion is configured to have a plane that intersects with the cylindrical surface.

4. The casing further comprises: A rear panel that provides a ventilation path from the intake The indoor unit has a heat exchanger disposed within the casing; a subcooler heat exchanger disposed upstream of the heat exchanger on the rear side and having a first coil disposed forward thereof; In the front-rear direction, a horizontal distance X between a center of the first coil and an end of the filter on the rear side and a minimum horizontal gap Y between the subcooler heat exchanger and the rear panel satisfy the following relationship: 0.5X≦Y≦1.0X The air conditioner according to claim 1 , which satisfies the above.

5. The diameter D of the crossflow fan and the horizontal length A in the front-to-back direction of the suction port have the following relationship: 1.5D≦A≦1.75D The air conditioner according to claim 1 , which satisfies the above.

6. The indoor unit further comprises: a heat exchanger disposed within the casing In a front-to-rear direction, a minimum horizontal distance P between the heat exchanger and the internal front panel and a length Q of a portion of the filter from a first position at the air inlet corresponding to a front end of the heat exchanger to a second position at the air inlet corresponding to the internal front panel satisfy the following relationship: 0.5Q≦P≦1.0Q The air conditioner according to claim 1 , which satisfies the above.

7. The inner front panel a first sloped section that slopes from a lower portion of the interior front panel away from the heat exchanger; a vertical section that is continuous with the first inclined section and extends upward in a substantially vertical direction; a second inclined section continuous with the vertical section; and the second inclined section is inclined at a predetermined angle θ ３ and tilts forward at the predetermined angle θ ３ is the angle relative to the plane of the filter, and is expressed as the following relationship: 45 degrees≦θ ３ <90 degrees The air conditioner according to claim 6, which satisfies the above.

8. An air conditioner described in any one of claims 1 to 7, wherein the edge portion has a sharpness equal to or sharper than that obtained by applying a fillet with a radius of 2 mm or less to the edge formed by the curved surface of the partial cylinder and the surface of the wall portion.

Images