EP3015774B1

EP3015774B1 - Air conditioner

Info

Publication number: EP3015774B1
Application number: EP13887920.0A
Authority: EP
Inventors: Atsushi Kono; Takashi Ikeda; Masahiko Takagi; Makoto Kurihara
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2013-06-28
Filing date: 2013-06-28
Publication date: 2019-10-16
Anticipated expiration: 2033-06-28
Also published as: JPWO2014207909A1; JP6104384B2; EP3015774A1; WO2014207909A1; EP3015774A4

Description

Technical Field

The present invention relates to an air conditioning apparatus.

Background Art

As a ceiling-concealed air conditioning apparatus of the related art, for example, an air conditioning apparatus disclosed in Patent Literature 1 is known. This air conditioning apparatus includes partition portions at longitudinal end portions of each of air outlets of a main body, and further includes guiding wall portions each being continuous to the partition portions, for guiding air blown from a heat exchanger to the air outlet. In this way, it is intended that, with those partition portions and guiding wall portions, the air flowing out from the corner portions of the heat exchanger is suitably guided to the air outlets.
European patent application, publication number EP 2413058 A1 discloses an air conditioner, casing and decorative panel.
International patent application, publication number WO 2012/169110 A1 discloses an air conditioning apparatus according to the preamble of claim 1.

Citation List

Patent Literature

[PTL 1] JP 2005-069586 A (claim 9, FIG. 2)

Summary of Invention

Technical Problem

In the air outlet of the ceiling-concealed air conditioning apparatus of the related art, the air stream is easily separated at an inlet portion of the air outlet when the air passing through the heat exchanger is caused to flow into the air outlet. In particular, the air stream is most liable to be separated at an air-outlet corner of the air outlet of the main body, which connects an air blower-side air duct wall and a side wall formed at the longitudinal end portion of the air outlet. Further, the separation of the air stream as described above is a cause of the airflow resistance in an air duct of the air outlet. In addition, the air velocity is lower at a downstream side of the separation region, thereby also causing a problem in that dew condensation easily occurs on an airflow direction flap installed on the air outlet due to undesired intake of the air from an inside of a room during a cooling operation.
Further, in the above-mentioned air conditioning apparatus disclosed in Patent Literature 1, the area of the air outlet is reduced due to the guiding wall portions, and hence there is a problem in that the airflow resistance in the air outlet is increased to reduce the airflow rate and increase noise.
The present invention has been made in order to solve the above-mentioned problems, and has an object to provide an air conditioning apparatus capable of preventing occurrence of separation while securing a sufficient area of an air outlet.

Solution to Problem

According to the present invention, there is provided an air conditioning apparatus, according to claim 1.
It is preferred that a part of the air outlet on the inner air duct wall side be formed so that an air duct is narrowed as approaching to a downstream side.
It is preferred that the pair of side walls of the air outlets be each divided by a division wall surface extending toward a longitudinal center portion of the air outlets. In this case, in plan view, the division wall surface may be inclined with respect to a line BL extending in a direction parallel to the inner air duct wall and the outer air duct wall so that side wall side of the division wall surface closes to the inner air duct wall.
It is preferred that the length L2 of the inner air duct wall of the air outlets be set smaller than a length L3 of a straight-line part of the heat exchanger, which extends in a longitudinal direction of the air outlets .

Advantageous Effect of Invention

According to the air conditioning apparatus of the one embodiment of the present invention, it is possible to prevent the occurrence of separation while securing a sufficient area of the air outlet.

Brief Description of Drawings

FIG. 1 is a side view for illustrating an internal structure of an air conditioning apparatus according to a first embodiment of the present invention.
FIG. 2 is a top view for illustrating an air outlet of the air conditioning apparatus according to the first embodiment.
FIG. 3 is a vertical section of an air outlet according to a second embodiment of the present invention.
FIG. 4 is a perspective view of an air outlet according to a third embodiment of the present invention.
FIG. 5 is a perspective view of a modified air outlet according to the third embodiment of the present invention.
FIG. 6 is a view for illustrating a fourth embodiment of the present invention in the same manner as that of FIG. 2.

Description of Embodiments

Now, an air conditioning apparatus according to embodiments of the present invention is described with reference to the accompanying drawings. Note that, in the drawings, the same reference symbols represent the same or corresponding parts.

First Embodiment

FIG. 1 is a schematic side view for illustrating an internal structure of an air conditioning apparatus according to a first embodiment of the present invention. More specifically, the air conditioning apparatus according to the first embodiment corresponds to an indoor unit of a so-called package air conditioner. FIG. 1 is an illustration of a state in which a principal part of a main body of the air conditioning apparatus is embedded in a ceiling of a room and a lower part of the main body faces the inside of the room.
At the lower part of the main body, one air inlet and a plurality of air outlets are formed, and in the inner part of the main body, there are provided an air blowing unit for generating a flow of air to be sucked into the main body through the air inlet and blown out to a target space through the air outlets, and a heat exchanger arranged in a flow passage of such air. For the above-mentioned matter, a specific example is described in detail below.
The ceiling-concealed air conditioning apparatus includes a turbofan 1 serving as the air blowing unit, a heat exchanger 3, and a plurality of air outlets 9. The main body is embedded at a back side of a ceiling surface 15 of the room (opposite side to the room) being the target space.
As one example, in the first embodiment, the main body includes a main-body top panel 5 having a rectangular shape in plan view, and four main-body side panels 4 extending downward from four sides of the main-body top panel 5. In other words, the main body is such a casing that an upper end surface of a rectangular tube body defined by the four main-body side panels 4 is closed by the main-body top panel 5.
At the lower part of the main body, namely, at an opened lower end surface of the above-mentioned casing, a decorative panel 6 is mounted on the main body in a freely removable manner. As illustrated in FIG. 1, the main-body top panel 5 is positioned above the ceiling surface 15, whereas the decorative panel 6 is positioned substantially flush with the ceiling surface 15.
In the vicinity of a center of the decorative panel 6, a suction grille 7 is provided as the inlet of air into the main body. A filter 8 for removing dust in the air passing through the suction grille 7 is provided to the suction grille 7.
As one example, in the first embodiment, the decorative panel 6 and the suction grille 7 each have a rectangular outer edge in plan view.
In a region between the outer edge of the decorative panel 6 and the outer edge of the suction grille 7, a plurality of air outlets 9 are formed. In the first embodiment, four air outlets 9 are formed in accordance with the structure in which the decorative panel 6 and the suction grille 7 each have the edge along four sides thereof, and the respective air outlets 9 are arranged so as to extend along the corresponding sides of the decorative panel 6 and the suction grille 7. Further, the four air outlets 9 are positioned so as to surround the suction grille 7 excluding a corner portion described later. An airflow direction flap 13 for adjusting a direction of the air to be blown out is provided at each air outlet 9.
A fan motor 2 is arranged at a center portion of the inside of the main body. The fan motor 2 is supported by a lower surface of the main-body top panel 5 (at an inner space side of the main body). The turbofan 1 is fixed to a rotational shaft of the fan motor 2, which extends downward. Further, a bellmouth 14 that defines a suction air duct extending from the suction grille 7 toward the turbofan 1 is provided between the turbofan 1 and the suction grille 7. The turbofan 1 sucks the air into the main body through the suction grille 7, and causes the air to flow out to an inside 17 of the room being the target space through the air outlet 9.
The heat exchanger 3 is arranged at a radially outer side of the turbofan 1. In other words, the heat exchanger 3 is arranged in a flow passage of the air generated in the main body by the turbofan 1, and exchanges heat between the air and a refrigerant. Further, the heat exchanger 3 has at least one corner portion 16 (see FIG. 2 described later) at a portion opposed to adjacent corners of the respective air outlets 9.
The heat exchanger 3 includes a plurality of fins arranged at predetermined intervals in a horizontal direction, and heat transfer tubes passing through the fins. The heat transfer tubes are connected to a known outdoor unit (not shown) through a connection pipe so that a cooled or heated refrigerant is supplied to the heat exchanger 3. Note that, the structures and shapes of the turbofan 1, the bellmouth 14, and the heat exchanger 3 are not particularly limited, but known structures and shapes are employed in the first embodiment.
In this structure, when the turbofan 1 is rotated, the air in the inside 17 of the room is sucked into the suction grille 7 of the decorative panel 6. Then, the air from which the dust is removed by the filter 8 is guided by the bellmouth 14 that defines the air inlet of the main body, and is then sucked into the turbofan 1. Further, the air sucked into the turbofan 1 from bottom to top is blown out in a horizontal and radially outward direction. When the air thus blown out passes through the heat exchanger 3, the heat is exchanged and the humidity is adjusted. After that, the air is blown out to the inside 17 of the room through each air outlet 9 with the flow direction switched to a downward direction.
Next, details of the air outlets 9 are described with reference to FIG. 1 and FIG. 2. FIG. 2 is a top view for illustrating one air outlet 9 according to this embodiment.
As illustrated in FIG. 1, each air outlet 9 is formed between the heat exchanger 3 and the main-body side panel 4 in plan view. As illustrated in FIG. 2, a part of the air outlet 9 at the center side of the main body is defined by an inner air duct wall 10 formed on the heat exchanger side, and a part of the air outlet 9 on the outer edge side of the decorative panel 6 is defined by an outer air duct wall 11 formed on the side panel side of the main-body. Both ends of the inner air duct wall 10 and both ends of the outer air duct wall 11 are connected to each other by a pair of side walls 12. The air stream passing through a straight-line part of the heat exchanger 3 is caused to flow into the air outlet 9 from the inner air duct wall 10 side, and the air stream passing through the corner portion 16 of the heat exchanger 3 is caused to flow into the air outlet 9 from the side wall 12 side of the adjacent air outlet 9. Note that, in the first embodiment, the inner air duct wall 10, the outer air duct wall 11, and the pair of side walls 12 each extend along the flow direction, namely, a direction perpendicular to the drawing sheet of FIG. 2. The opening area and the opening shape of the air outlet 9 as seen in FIG. 2 are kept uniform in a range from an inlet end of the air outlet 9 to an outlet end thereof.
According to the invention, a length L2 of the inner air duct wall 10 is larger than a length L1 of the outer air duct wall 11 (dimension of the air duct wall extending along a longitudinal direction of the air outlet, namely, dimension in a direction along the above-mentioned side). For the above-mentioned matter, more specific description is given. In the first embodiment, in plan view, that is, on the inlet side with respect to the outlet of the air, the inner air duct wall 10 and the outer air duct wall 11 exhibit straight lines extending substantially parallel to each other. Further, assuming that a line passing through centers of lengthwise directions of those inner air duct wall 10 and outer air duct wall 11 and orthogonal to extending directions of those inner air duct wall 10 and outer air duct wall 11 is defined as a center line CL, and a vicinity of the center line CL is defined as an air outlet center, the above-mentioned relationship that the length L1 of the outer air duct wall 11 is smaller than the length L2 of the inner air duct wall 10 is attained by forming at least one of the side walls 12 to include a deviated portion extending away from the air outlet center as approaching to the inner air duct wall 10. The structure illustrated in FIG. 2 is an example of a case where both the side walls 12 each have the deviated portion as a part of the side wall 12.
The pair of side walls 12 each include a straight portion 12a extending from an end portion on the outer air duct wall 11 side toward the inner air duct wall 10 substantially in parallel to the center line CL (so as to have a substantially constant distance from the air outlet center), and an inclined portion 12b formed in a range from a portion connected to the straight portion 12a to an end portion on the inner air duct wall 10 side. Further, the inclined portion 12b corresponds to the deviated portion, and the inclined portion 12b extends straight and is inclined so as to be away from the air outlet center as approaching to the inner air duct wall 10.
Note that, FIG. 2 is merely an example for obtaining the relationship that the length L1 of the outer air duct wall 11 is smaller than the length L2 of the inner air duct wall 10. Thus, the deviated portion may be realized, for example, as the inclined portion 12b itself by forming the entire inclined portion 12b to extend straight and be inclined so as to be away from the air outlet center as approaching to the inner air duct wall 10 in plan view. Alternatively, the deviated portion may be realized by partially or entirely curving the inclined portion 12b so that the curved part has a portion displaced away from the air outlet center as approaching to the inner air duct wall 10 in plan view. Further, in this case, the curved part may be a curved part convexed at the air outlet center side, or conversely, a curved part concaved at the air outlet center side.
As described above, the length L1 of the outer air duct wall 11 is smaller than the length L2 of the inner air duct wall 10, and hence a length of the part of the air outlet 9 on the main body center side, that is, a length of a part on the heat exchanger side is relatively increased. In other words, it can be understood that air passages at a pair of corners of the air outlet 9, at which the inner air duct wall 10 and each of the pair of side walls 12 intersect with each other, are relatively enlarged.
According to the air conditioning apparatus of the first embodiment, which is constructed as described above, the corners of the air outlet at the inlet on the heat exchanger side are relatively enlarged, and hence the air stream passing through the corner portion of the heat exchanger can be taken into the air outlet efficiently in a larger amount, thereby being capable of reducing the separation of the air stream without involving the reduction of the area of the air outlet. Further, both the above-mentioned avoidance of the reduction of the area of the air outlet and reduction of the separation of the air stream are attained. Thus, it is possible to reduce the airflow resistance, and therefore reduce noise, secure a sufficient airflow rate, and to achieve a high power saving rate. Further, both the avoidance of the reduction of the area of the air outlet and the reduction of the separation of the air stream are attained. Thus, decrease in air velocity can be suppressed, which also leads to suppression of undesired intake of the air as a result. Therefore, dew condensation can be prevented.

Second Embodiment

Next, a second embodiment of the present invention is described with reference to FIG. 3. FIG. 3 is a view for illustrating a vertical section of an air outlet (cross-section taken along the line III-III of FIG. 2, namely, cross-section including the center line CL as a normal) according to the second embodiment. Note that, the second embodiment is similar to the above-mentioned first embodiment except for the parts described below.
In an air outlet 109 of the second embodiment, an enlarged portion on the inner air duct wall 10 side is formed so that an air duct is narrowed as approaching to a downstream side (lower side in the drawing sheet of FIG. 3), and the air outlet 109 is constructed such that the area of an outlet end (downstream end) 109a of the air outlet 109 is smaller than the area of an inlet end (upstream end) 109b thereof. The above-mentioned length L2 of the inner air duct wall 10 of the air outlet 109 in the longitudinal direction corresponds to a length secured in a vicinity of the inlet end 109b.
Also in the air conditioning apparatus of the second embodiment, which is constructed as described above, similar advantages to those of the first embodiment described above are attained. In addition, in the second embodiment, the air duct of the air outlet is narrowed as approaching to the downstream side of the air outlet, thereby being capable of promoting re-adhesion of the air stream, reducing a separation region for the air stream at the downstream side of the air outlet, and increasing the air velocity at a portion in the outlet end of the air outlet on the inner air duct wall side. Thus, it is possible to further reduce pressure loss that may be caused due to the separation of the air stream, achieve a high power saving rate, reduce the air blowing noise, and to prevent the dew condensation that may be caused by the undesired intake of the air from the inside of the room.

Third Embodiment

Next, a third embodiment of the present invention is described with reference to FIG. 4 and FIG. 5. FIG. 4 and FIG. 5 are perspective views of an air outlet according to the third embodiment of the present invention. Note that, the third embodiment is similar to the above-mentioned second embodiment except for the parts described below.
An air outlet 209 of the third embodiment has a structure in which side walls 212 at longitudinal end portions of the air outlet 209 are each divided by a division wall surface 218 extending toward a longitudinal center portion of the air outlet 209. More specifically, as illustrated in FIG. 4, a portion of the side wall 212 on the downstream side with respect to the division wall surface 218 has a straight portion 212c extending straight along the flow direction and a direction orthogonal to the inner air duct wall 10 and the outer air duct wall 11, and a portion of the side wall 212 on the outer air duct wall 11 side with respect to the division wall surface 218 also has the straight portion 12a extending straight along the flow direction and the direction orthogonal to the inner air duct wall 10 and the outer air duct wall 11. On the other hand, a portion of the side wall 212 on the inner air duct wall 10 side with respect to the division wall surface 218 has an inclined surface 212d inclined in a direction in which a distance between the straight portion 12a and the straight portion 212c in the longitudinal direction is increased as approaching to an inlet end 209b. In other words, an interval L between a pair of the right and left inclined surfaces 212d (only one inclined surface is illustrated in FIG. 4) in the longitudinal direction is reduced as approaching from the inlet end 209b to the outlet end 209a, and a most downstream portion of the inclined surface 212d is connected to the straight portion 212c.
In FIG. 4, in plan view, the division wall surface 218 extends in a direction orthogonal to the straight portion 12a and the straight portion 212c, namely, a direction parallel to the inner air duct wall 10 and the outer air duct wall 11. However, instead of the above-mentioned division wall surface 218, a division wall surface 218' illustrated in FIG. 5 may be formed. FIG. 5 is a modification example of the third embodiment, and in plan view, the division wall surface 218' is inclined with respect to a line BL extending in the direction parallel to the inner air duct wall 10 and the outer air duct wall 11 so that a part on the side wall 212 side approaches to the inner air duct wall 10. Thus, an interval L between a pair of inclined surfaces 212d' in the longitudinal direction is reduced as approaching from the inlet end 209b to the outlet end 209a, and widths W of the pair of inclined surfaces 212d' , which are orthogonal to the longitudinal direction (dimensions in an opposing direction of the inner air duct wall 10 and the outer air duct wall 11), are also reduced.
Also in the air conditioning apparatus of the third embodiment, which is constructed as described above, the similar advantages to those of the above-mentioned first embodiment described above are attained, and further similar advantages to those of the above-mentioned second embodiment are attained. In addition, in the third embodiment, the division wall surfaces extending toward the longitudinal center portion are formed on the side walls of the air outlet. Thus, the air stream flowing into the air outlet from the side wall side at the longitudinal end portion of the air outlet, which is easily concentrated on the outer air duct wall side of the air outlet, can be sufficiently supplied also toward the inner air duct wall side of the air outlet. Therefore, as compared to the structure having no division wall surface, the airflow rate at a part of the air outlet on the inner air duct wall side can be increased, and the separation of the air stream can be prevented. Also with this, it is possible to reduce the pressure loss that may be caused due to the separation of the air stream, achieve a high power saving rate, and to reduce the air blowing noise.

Fourth Embodiment

Next, a fourth embodiment of the present invention is described with reference to FIG. 6. FIG. 6 is a view for illustrating the fourth embodiment of the present invention in the same manner as that of FIG. 2. Note that, the fourth embodiment is similar to the above-mentioned third embodiment except for the parts described below.
In the fourth embodiment, a length L2 of an inner air duct wall 10 of an air outlet 309 is set smaller than a length L3 of a straight-line part of the heat exchanger 3, which extends in a longitudinal direction of the air outlet 309.
Also in the air conditioning apparatus of the fourth embodiment, which is constructed as described above, similar advantages to those of the above-mentioned third embodiment are attained. In addition, in the fourth embodiment, the length L3 of the straight-line part of the heat exchanger is larger than the length L2 of the inner air duct wall of the air outlet. Thus, the air flowing out of the heat exchanger easily flows into the air outlet perpendicularly from the inner air duct wall side of the air outlet. Further, the air stream, which passes through the corner portion of the heat exchanger to flow into the air outlet from the side wall side at the longitudinal end portion of the air outlet, also easily flows perpendicularly into the air outlet without concentrating on the outer air duct wall side of the air outlet. Therefore, the air stream easily flows into the air outlet at an even airflow rate, and hence the separation of the air stream is less easily caused. Also with this, it is also possible to reduce the pressure loss that may be caused due to the separation of the air stream, achieve a high power saving rate, and to reduce the air blowing noise.
Note that, the fourth embodiment may also be carried out in combination with the above-mentioned first or second embodiment.
Although the details of the present invention are specifically described above with reference to the preferred embodiments, it is apparent that persons skilled in the art may adopt various modifications based on the basic technical concepts and teachings of the present invention as defined in the claims.
Further, as examples of application of the present invention, the present invention is widely applicable to an indoor unit that constructs a refrigeration cycle system. For example, needless to say, the present invention is widely applicable to an indoor unit of an air conditioning apparatus, or to various other apparatus and facilities in which an air blower is installed.

Reference Signs List

1 turbofan (air blowing unit), 3 heat exchanger, 4 main-body side panel, 7 suction grille (air inlet), 9, 109, 209 air outlet, 10 inner air duct wall, 11 outer air duct wall, 12, 212 side wall, 16 corner portion, 218, 218' division wall surface

Claims

An air conditioning apparatus, comprising:
a main body having a rectangular tube shape, the main body comprising:
side panels (4) forming side surfaces;

a top panel (5) having a rectangular shape in plan view;

a decorative panel (6) forming a lower surface;

an air inlet (7) formed at a center portion of the decorative panel (6);

a plurality of air outlets (9, 109, 209, 309) formed in the decorative panel (6) and arranged between an outer edge of the decorative panel (6) and the air inlet (7);

an air blowing unit (1) housed inside the main body, for sucking air into the main body through the air inlet (7) and causing the air to flow out of the main body through the air outlets (9, 109, 209, 309); and

a heat exchanger (3) housed inside the main body and arranged in a flow passage of the air flowing from the air inlet (7) to the air outlets (9, 109, 209, 309),

wherein the air outlets (9, 109, 209, 309) are formed by an inner air duct wall (10) formed on the heat exchanger side, an outer air duct wall (11) formed on the side panel side, and a plurality of side walls (12, 212) connecting both ends of the inner air duct wall and both ends of the outer air duct wall to each other, and

wherein, when seen in plan view, an inlet end of the inner air duct wall (10) is a straight line between the side walls, and

when seen in plan view, an inlet end of the outer air duct wall (11) is a straight line between the side walls, the inlet end of the inner air duct wall (10) and the inlet end of the outer air duct wall (11) extending substantially parallel to each other; characterized in that

a length (L2) of the inlet end of the inner air duct wall (10) is larger than a length (L1) of the inlet end of the outer air duct wall (11).
An air conditioning apparatus according to claim 1, wherein a part of the air outlets on the inner air duct wall side are formed so that an air duct is narrowed as approaching to a downstream side.
An air conditioning apparatus according to any one of claims 1 to 2, wherein the plurality of side walls of the air outlets (209) are each divided by a division wall surface (218, 218') extending toward a longitudinal center portion of the air outlets (209).
An air conditioning apparatus according to claim 3, wherein, in plan view, the division wall surface (218, 218') is inclined with respect to a line (BL) extending in a direction parallel to the inner air duct wall (10) and the outer air duct wall (11) so that the plurality of side wall side of the division wall surface (218, 218') closes to the inner air duct wall (10).
An air conditioning apparatus according to any one of claims 1 to 4, wherein the length (L2) of the inner air duct wall (10) of the air outlets (309) is set smaller than a length (L3) of a straight-line part of the heat exchanger (3), which extends in a longitudinal direction of the air outlets (309).