JP2023070306A - Ceiling embedded type air conditioner - Google Patents

Abstract

To provide a ceiling embedded type air conditioner having further improved efficiency.SOLUTION: A ceiling embedded type air conditioner comprises: a motor comprising an output shaft capable of rotating around an axis extending in a vertical direction; a turbo fan attached to the output shaft; a heat exchanger surrounding the turbo fan from an outer peripheral side, and through which air sent under pressure by the turbo fan passes; and a drain pan provided on a lower side of the heat exchanger, and in which an opening part for discharging the air having passed through the heat exchanger is formed. In a wall surface of the opening part, a concave part recessed outward from the wall surface and extending in the direction of the axis is formed.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to ceiling-mounted air conditioners.

As an example of an air conditioner, a ceiling-embedded air conditioner as disclosed in Patent Document 1 below is widely used. A ceiling-mounted air conditioner includes a main body case embedded in an indoor ceiling, a motor having an output shaft that rotates around an axis extending in the vertical direction inside the case, a turbo fan, and a turbo fan provided on the intake side of the turbo fan. It mainly includes a bell mouth, a heat exchanger surrounding the turbofan, a drain pan, and a panel containing an inlet, an outlet, and an outlet louver. A drain pan is provided to catch moisture condensed on the surface of the heat exchanger. Further, the drain pan is formed with a plurality of openings for blowing out the flow of air that has passed through the heat exchanger.

Indoor air is taken into the case body from the central portion of the case body by rotating the turbo fan. This air is pressure-fed to the outer peripheral side by a turbo fan, passes through a heat exchanger, becomes cold air or warm air, and is supplied indoors from the outlet of the panel through the opening of the drain pan. Here, in order to improve the efficiency of the ceiling-mounted air conditioner, it is important to reduce the pressure loss of the air flow passing through the opening. In the apparatus disclosed in Patent Document 1 below, a protrusion is provided on the inner wall surface of the drain pan on the main body case side. The protrusions make the flow velocity distribution at the openings uniform, preventing condensation on the back side of the louver, reducing pressure loss that causes noise, and improving the wind direction controllability of the louver.

JP 2007-333356 A

However, when the protrusions as described above are provided, separation on the wall surface is likely to occur, and secondary flow may occur on the wall surface due to the influence of turbulence and separation of the flow at the corners of the outlet. As a result, the efficiency of the ceiling-mounted air conditioner decreases.

The present disclosure has been made to solve the above problems, and an object of the present disclosure is to provide a ceiling-mounted air conditioner with further improved efficiency.

In order to solve the above problems, a ceiling-mounted air conditioner according to the present disclosure includes a motor having an output shaft rotatable around an axis extending in the vertical direction, a turbo fan attached to the output shaft, and the turbo A heat exchanger that surrounds the fan from the outer peripheral side and through which the air pressure-fed by the turbo fan passes; and a drain pan that is provided below the heat exchanger and has an opening for blowing out the air that has passed through the heat exchanger. and a recess is formed in the wall surface of the opening, recessed outward from the wall surface and extending in the axial direction.

According to the present disclosure, it is possible to provide a ceiling-mounted air conditioner with improved efficiency.

1 is a cross-sectional view showing the configuration of a ceiling-mounted air conditioner according to an embodiment of the present disclosure; FIG. 2 is a plan view showing the configuration of a drain pan according to an embodiment of the present disclosure; FIG. 4 is an enlarged plan view showing the configuration of the opening according to the embodiment of the present disclosure; FIG. 4 is an enlarged cross-sectional view showing the configuration of the opening according to the embodiment of the present disclosure; FIG. FIG. 10 is a plan view showing a modification of the recess according to the embodiment of the present disclosure; FIG. 11 is a plan view showing a further modification of the recess according to the embodiment of the present disclosure;

(Configuration of ceiling-mounted air conditioner)
A ceiling-mounted air conditioner 100 according to a first embodiment of the present disclosure will be described below with reference to FIGS. 1 to 4 . As shown in FIG. 1, the ceiling-mounted air conditioner 100 includes a main body case 1, a motor 2, a turbo fan 4, a heat exchanger 5, a bell mouth 6, and a drain pan 7.

The body case 1 is embedded in the ceiling space 90 of the building. The body case 1 has a rectangular shape when viewed from below, and is recessed upward to form a space inside. Specifically, the body case 1 has a panel 1a exposed on the ceiling surface 90a and a box-shaped cabinet 1b provided above the panel 1a. The panel 1a has a panel body 11, which is a rectangular frame, and a grill 12 as a suction port 11a provided at the center of the lower portion. The panel main body 11 forms a blowout port 11b around the suction port 11a.

The motor 2 is provided at the center of the bottom surface 1s facing downward inside the cabinet 1b. The motor 2 has a motor body 21 that accommodates coils, magnets, and the like, and an output shaft 22 that projects vertically downward from the motor body 21 . The output shaft 22 is rotationally driven around an axis O extending in the vertical direction.

A turbo fan 4 is attached to the output shaft 22 . The turbofan 4 includes a disc-shaped main plate 3 extending radially outward and centered on the axis O, a plurality of main blades 41 arranged at intervals in the circumferential direction, and an annular shape covering the main blades 41 from below. a shroud 42; As the output shaft 22 rotates, the turbo fan 4 fixed to the output shaft 22 by the main plate 3 rotates. sent radially outward.

An annular heat exchanger 5 surrounding the turbofan 4 is provided radially outside the turbofan 4 . The heat exchanger 5 is part of a refrigerant circuit with a refrigeration cycle.

The air sent to the heat exchanger 5 by the turbofan 4 exchanges heat with the refrigerant when passing through the heat exchanger 5 . As a result, the air that has flowed out to the outer peripheral side of the heat exchanger 5 becomes cool air or warm air. This air flows downward along the side surface of the cabinet 1b, passes through the opening 7h of the drain pan 7 (described later), and is supplied into the room from the outlet 11b of the panel 1a.

A drain pan 7 provided below the heat exchanger 5 is a dish-shaped member for receiving condensed water generated on the surface of the heat exchanger 5 . Although details will be described later, the drain pan 7 is formed with a plurality of openings 7h for guiding the air that has passed through the heat exchanger 5 to the blowout port 11b. A portion other than these openings 7h covers the heat exchanger 5 from below when viewed from the axis O direction.

A bell mouth 6 is arranged in the center of the drain pan 7 . The bell mouth 6 is provided to guide the air introduced from the suction port 11 a and send it to the turbo fan 4 . The bell mouth 6 has a conical shape by gradually decreasing in diameter from the bottom to the top. One end (upper side) of the bell mouth 6 in the direction of the axis O is surrounded by the shroud 42 described above from the outer peripheral side.

(Configuration of drain pan)
Next, the configuration of the drain pan 7 will be described in detail. As shown in FIG. 2, the drain pan 7 has a rectangular shape when viewed from the axis O direction. Four corners of the drain pan 7 are appropriately notched in accordance with the shape of the main body case 1 . A plurality of (for example, two each) openings 7h are formed in each of the four sides of the drain pan 7 . A plurality of (two as an example) openings 7h are formed in one side, and a girder 8 is provided between each opening 7h. The girder 8 is provided to prevent the strength of the drain pan 7 from being lowered and to increase the flow velocity due to the formation of the opening 7h.

As shown in an enlarged view in FIG. 3, each opening 7h has a rectangular shape formed by a first end surface 71 that is a long side and a second end surface 72 that is a short side. The first end face 71 extends in the first direction D1 along the sides of the drain pan 7, and the second end face 72 extends in the second direction D2 perpendicular to the first direction D1. A side surface 82 of the girder 8 forms part of the second end surface 72 . A corner portion formed by the first end surface 71 and the second end surface 72 is formed with a concave portion 7r.

The recess 7r is formed only on the first end surface 71 at the corner formed by the side surface 82 of the girder 8 and the first end surface 71 . In other words, the concave portion 7r is formed by retreating (recessing) only the first end surface 71 in the second direction D2. On the other hand, at the corner formed by the first end surface 71 and the second end surface 72 (that is, the surface other than the side surface 82 of the girder 8), the recess 7r is formed so that the first end surface 71 recedes in the second direction D2 and The two end faces 72 are formed by retreating in the first direction D1. As a result, each recess 7r has a rectangular shape when viewed from the axis O direction.

Moreover, as shown in FIG. 4, each recessed part 7r penetrates the drain pan 7 in the direction of the axis O. As shown in FIG. Furthermore, as shown in the figure, a curved surface 7t is formed on the first end surface 71 positioned radially inward with respect to the axis O. As shown in FIG. 7 t of curved surfaces bulge so that it may become convex in the second direction. 7 t of curved surfaces are provided in order to rectify|straighten the blowing flow from the heat exchanger which passes 7 h of openings. The recess 7r extends through the curved surface 7t in the direction of the axis O. As shown in FIG. In addition, the other first end surface 71 facing the curved surface 7t spreads along the axis O. As shown in FIG.

(Effect)
Next, the operation of the ceiling-mounted air conditioner 100 will be described. When operating the ceiling-mounted air conditioner 100, the motor 2 is first driven. By driving the motor 2, the output shaft 22 and the turbo fan 4 rotate around the axis O. As shown in FIG. Air in the room is taken in from the suction port 11a by the rotation of the turbo fan 4. - 特許庁This air forms the main stream by being pumped radially outward by the turbo fan 4 via the bell mouth 6 . The main stream flows from the inner side to the outer side in the radial direction from the bottom to the top. This main flow exchanges heat with the refrigerant by passing through the heat exchanger 5, becomes cold air or warm air, and then passes through the opening 7h of the drain pan 7 and is supplied into the room from the outlet 11b of the panel 1a.

Here, in order to improve the efficiency of the ceiling-mounted air conditioner 100, it is important to reduce the pressure loss of the air flow passing through the opening 7h. Therefore, in the present embodiment, the curved surface 7t is provided on the first end surface 71 on one side of the opening 7h as described above. The curved surface 7t rectifies the flow on the wall surface of the first end surface 71 in the opening 7h, thereby making the flow velocity distribution of the air uniform.

On the other hand, at the corners of the opening 7h, the flow from the first end face 71 side and the flow from the second end face 72 side merge, causing turbulence and separation of the flows. In addition, a secondary flow is generated on the first end surface 71, increasing the pressure loss.

Therefore, in the present embodiment, the recesses 7r are formed at the corners of the opening 7h as described above. According to this configuration, the flow turbulence and separation occurring at the corners of the opening 7h can be collected in the recess 7r by allowing the converging air flows to pass through the recess 7r. As a result, pressure loss can be reduced without reducing the effective area of the opening 7h. As a result, the efficiency of the ceiling-mounted air conditioner 100 can be further improved.

Furthermore, according to the above configuration, the air flows along the curved surface 7t that is convex in the second direction D2, thereby rectifying the flow on the wall surface and making the flow velocity distribution uniform. On the other hand, since the concave portion 7r is formed so as to penetrate the curved surface 7t, secondary flow generated on the wall surface of the curved surface 7t can be suppressed, and an increase in pressure loss can be avoided.

In addition, according to the above configuration, since the recess 7r is formed at the corner formed by the girder 8 (side surface 82), which is unavoidably arranged for strength reasons, and the first end surface 71, the turbulence of the flow generated at the corner is reduced. and peeling can be reduced. At the corner formed by the girder 8 and the first end face 71, the girder 8 itself is not machined, and only the first end face 71 is retracted to form the recess 7r. As a result, a reduction in strength of the girder 8 can be avoided, and the drain pan 7 can be smoothly injection-molded.

In addition, according to the above configuration, since the recess 7r has a rectangular shape, the maximum cross-sectional area of the recess 7r when viewed from the direction of the axis O can be ensured. As a result, most of the turbulent or separated flow can be concentrated in the recess 7r.

The embodiments of the present disclosure have been described above. Various changes and modifications can be made to the above configuration without departing from the gist of the present disclosure. For example, in the above-described embodiment, an example in which each concave portion 7r has a rectangular shape has been described. However, the shape of the recess 7r is not limited to a rectangle, and may be arc-shaped as shown in FIG. 5 as a modification. In this case, no new corner is formed in the recess 7r. This can further reduce the occurrence of flow turbulence and separation.

Further, in the above embodiment, the dimensions of each recess 7r are not particularly limited. It is desirable that the dimensions of the recesses 7r are individually determined according to the dimensions of the openings 7h and the flow rate of the air. As an example, it is conceivable that the recess 7r satisfies the following dimensional conditions. As shown in FIG. 6, the dimension of the recess 7r in the first direction D1 is W, the dimension in the second direction D2 is B, the width dimension of the girder 8 (dimension in the first direction D1) is D, and the opening 7h When the dimension in the second direction D2 is S, and the projecting dimension of the curved surface 7t is T, it is desirable to satisfy the following equations (1) to (4).
0.5D<W<2D (1)
0.5D<W<1/3S (2)
T<B<D (3)
T<B<1/3S (4)

Furthermore, in the above-described embodiment, the example in which the recesses 7r are formed only at the corners of the opening 7h has been described. However, the locations where the recesses 7r are formed are not limited to the corners. For example, it is possible to form a plurality of recesses 7r at intervals on the first end face 71 or the second end face 72 . According to such a configuration, it is possible to further reduce the occurrence of secondary flow and separation described above.

<Appendix>
The ceiling-mounted air conditioner 100 described in each embodiment is understood, for example, as follows.

(1) A ceiling-mounted air conditioner 100 according to a first aspect includes a motor 2 having an output shaft 22 rotatable around an axis O extending in the vertical direction, and a turbo fan 4 attached to the output shaft 22. , a heat exchanger 5 that surrounds the turbofan 4 from the outer peripheral side and through which the air pressure-fed by the turbofan 4 passes; A drain pan 7 having an opening 7h for blowing out is formed, and a recess 7r is formed in the wall surface of the opening 7h so as to be recessed outward from the wall surface and extend in the direction of the axis O. As shown in FIG.

According to the above configuration, the flow of air passes through the recessed portion 7r, so that turbulence and separation of the flow occurring in the vicinity of the wall surface of the opening 7h can be concentrated in the recessed portion 7r. As a result, the pressure loss can be reduced without reducing the effective area of the opening 7h as compared with the case where the projection is provided instead of the recess 7r.

(2) In the ceiling-mounted air conditioner 100 according to the second aspect, the opening 7h includes a first end surface 71 extending in the first direction D1 and a second end surface 71 extending in the second direction orthogonal to the first direction D1. The recess 7r is formed at a corner formed by the first end surface 71 and the second end surface 72. As shown in FIG.

It is known that the flow along the first end face 71 and the flow along the second end face 72 merge at the corners of the opening 7h, causing turbulence and separation of the flows. According to the above configuration, since the recesses 7r are formed at such corners, it is possible to more positively reduce turbulence and separation of the flow.

(3) In the ceiling-embedded air conditioner 100 according to the third aspect, the first end surface 71 is the curved surface 7t that is convex in the second direction D2, and the concave portion 7r extends along the curved surface 7t. It penetrates in the direction of the axis O.

According to the above configuration, the air flows along the curved surface 7t that is convex in the second direction D2, so that the flow velocity distribution can be made uniform. On the other hand, since the recess 7r is formed so as to penetrate the curved surface 7t, it is also possible to avoid an increase in the secondary flow generated on the wall surface of the curved surface 7t.

(4) In the ceiling-mounted air conditioner 100 according to the fourth aspect, a plurality of openings 7h are arranged in the first direction D1 via girders 8 extending in the second direction D2, and the recesses 7r are , is formed at the corner formed by the girder 8 and the first end surface 71 .

According to the above configuration, since the recess 7r is formed at the corner formed by the girder 8 and the first end face 71, which are unavoidably arranged for strength reasons, it is possible to reduce flow turbulence and separation occurring at the corner. can.

(5) In the ceiling-mounted air conditioner 100 according to the fifth aspect, the concave portion 7r has a rectangular shape when viewed from the axis O direction.

According to the above configuration, since the recess 7r has a rectangular shape, the maximum cross-sectional area of the recess 7r when viewed from the direction of the axis O can be ensured. As a result, most of the turbulent or separated flow can be concentrated in the recess 7r.

(6) In the ceiling-mounted air conditioner 100 according to the sixth aspect, the concave portion 7r has an arc shape when viewed from the axis O direction.

According to the above configuration, since the concave portion 7r is arc-shaped, no new corner portion is formed in the concave portion 7r. This can further reduce flow turbulence and separation.

100 Ceiling-embedded air conditioner 1 Main body case 1a Panel 1b Cabinet 1s Bottom surface 2 Motor 3 Main plate 4 Turbo fan 5 Heat exchanger 6 Bell mouth 7 Drain pan 7h Opening 7r Recess 7t Curved surface 8 Girder 11 Panel body 11a Suction port 11b Blow Outlet 12 Grille 21 Motor body 22 Output shaft 32 Reduced diameter portion 41 Main wing 42 Shroud 71 First end face 72 Second end face 82 Side O Axis

Claims (6)

a motor having an output shaft rotatable around an axis extending in the vertical direction;
a turbofan attached to the output shaft;
a heat exchanger surrounding the turbofan from the outer peripheral side and through which the air pumped by the turbofan passes;
a drain pan provided below the heat exchanger and having an opening for blowing out the air that has passed through the heat exchanger;
with
A ceiling-embedded air conditioner, wherein a wall surface of the opening is formed with a recess recessed outwardly from the wall surface and extending in the axial direction. The opening has a rectangular shape formed by a first end surface extending in a first direction and a second end surface extending in a second direction perpendicular to the first direction, and the recess includes the first end surface and the 2. The ceiling-embedded air conditioner according to claim 1, which is formed at a corner formed by the second end face. 3. The ceiling-embedded air conditioner according to claim 2, wherein the first end surface is a curved surface that protrudes in the second direction, and the recess extends through the curved surface in the axial direction. 4. A plurality of said openings are arranged in said first direction via girders extending in said second direction, and said recesses are formed at corners formed by said girders and said first end face. The ceiling-embedded air conditioner described in . The ceiling-embedded air conditioner according to any one of claims 1 to 4, wherein the recess has a rectangular shape when viewed from the axial direction. The ceiling-embedded air conditioner according to any one of claims 1 to 4, wherein the recess has an arc shape when viewed from the axial direction.

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