EP2581679A1

EP2581679A1 - Cabinet for air conditioning device, and air conditioning device using same

Info

Publication number: EP2581679A1
Application number: EP11792316.9A
Authority: EP
Inventors: Hiraku Kunita; Masahiro Tubono; Masakazu Ito; Takayuki Suzuki
Original assignee: Mitsubishi Heavy Industries Ltd
Current assignee: Mitsubishi Heavy Industries Thermal Systems Ltd
Priority date: 2010-06-09
Filing date: 2011-05-30
Publication date: 2013-04-17
Also published as: WO2011155359A1; JP2011257068A; EP2581679A4

Abstract

An object is to provide an air-conditioning-apparatus cabinet (11) capable of suppressing deformation of a top panel provided with a plurality of air blowers, without causing an increase in weight, and also to provide an air conditioning apparatus having the cabinet. The cabinet includes a top panel (21) to which a plurality of air blowers (12a,12b) are attached on an undersurface thereof via attachment sections (24a,24b); a side panel (22) that extends downward from a peripheral edge of the top panel (21) to surround a space below the top panel (21); and central reinforcing ribs (25) that extend in a direction perpendicular to an imaginary straight line connecting the attachment sections (24a,24b).

Description

Technical Field

The present invention relates top an air-conditioning-apparatus cabinet that is used for a ceiling-embedded indoor unit of an air conditioning apparatus and to an air conditioning apparatus using the cabinet.

Background Art

A general ceiling-embedded indoor unit of an air conditioning apparatus includes an air blower formed of a centrifugal fan and a fan motor; a heat exchanger that surrounds the air blower and is disposed in the airflow path of the air blower; and an air-conditioning-apparatus cabinet (hereinafter, referred to as "cabinet.") that accommodates the air blower and the heat exchanger. The cabinet is formed in a box shape having a top panel to which the air blower is attached on the undersurface thereof and side panels that surround the four sides of the top panel.
Since the centrifugal fan and the fan motor, which constitute the air blower, are attached to the undersurface of the top panel of the cabinet, if the strength of the top panel is insufficient, an attachment section on the top panel for the air blower is elastically deformed due to the weight of the air blower so as to protrude downward from the peripheral edge (specifically, the top panel is deformed so as to become convex downward).
Thus, in order to distribute the downward load of the air blower (the weight of the air blower) exerted on the vicinity of the attachment section, double-layered ribs are provided on the top panel around the attachment section for the air blower, or ribs whose individual widths are gradually increased from the attachment section for the air blower toward the peripheral edge are provided (for example, PTLs 1 to 3).

Citation List

Patent Literature

{PTL 1} Publication of Japanese Patent No. 3807436
{PTL 2} Japanese Unexamined Patent Application, Publication No. 2006-292312
{PTL 3} Japanese Unexamined Patent Application, Publication No. 2007-192415

Summary of Invention

Technical Problem

However, the inventions disclosed in PTLs 1 to 3 relate to cabinets in which a single air blower is provided on a single top panel. In a case of a cabinet in which a plurality of air blowers, are provided on a single top panel, deformation of a portion of the top panel between air blowers cannot be sufficiently suppressed even if ribs such as those described above are employed.
The present invention has been made in view of such circumstances, and an object thereof is to provide an air-conditioning-apparatus cabinet capable of suppressing deformation of a top panel provided with a plurality of air blowers, without causing an increase in weight, and also to provide an air conditioning apparatus using the cabinet.

{Solution to Problem}

In order to solve the above-described problems, the present invention provides the following solutions.
Specifically, according to a first aspect, the present invention provides an air-conditioning-apparatus cabinet including: a top panel to which a plurality of air blowers are attached on an undersurface thereof via attachment sections; a side panel that extends downward from a peripheral edge of the top panel to surround a space below the top panel; and a central reinforcing rib that extends in a direction perpendicular to an imaginary straight line connecting the attachment sections.
The central reinforcing rib is provided so as to extend in the direction perpendicular to the imaginary straight line connecting the attachment sections provided on the top panel. Thus, by attaching the air blowers to the undersurface of the top panel, even when the downward loads thereof are exerted on the attachment sections to cause downward deformation of the portion of the top panel between the air blowers, the downward loads exerted on the vicinities of the attachment sections can be distributed over the entire top panel via the central reinforcing rib to support the air blowers. Therefore, the deformation of the portion of the top panel between the air blowers can be reduced.
In the above-described air-conditioning-apparatus cabinet according to the first aspect of the present invention, a plurality of the central reinforcing ribs are provided.
The plurality of central reinforcing ribs are provided between the air blowers. Thus, by attaching the air blowers to the undersurface of the top panel, even when the downward loads thereof are exerted on the attachment sections to cause downward deformation of the portion of the top panel between the air blowers, the downward loads exerted on the vicinities of the attachment sections can be distributed over the entire top panel via the central reinforcing ribs to support the air blowers. Therefore, the deformation of the portion of the top panel between the air blowers can be reduced.
The above-described air-conditioning-apparatus cabinet according to the first aspect of the present invention further includes, in vicinities of the attachment sections, a plurality of peripheral-edge reinforcing ribs whose individual widths are gradually increased from the vicinities of the attachment sections toward the peripheral edge.
The peripheral-edge reinforcing ribs, whose individual widths are gradually increased from each of the attachment sections toward the peripheral edge (widths in the circumferential direction from each of the attachment sections), are provided in the vicinities of the attachment sections. Thus, even when the downward loads are exerted on the attachment sections, the downward loads on the vicinities of the attachment sections can be distributed over the peripheral edge via the peripheral-edge reinforcing ribs. Thus, the downward loads exerted on the vicinities of the attachment sections can be distributed over the entire top panel via the peripheral-edge reinforcing ribs to support the air blowers. Therefore, the deformation of the top panel can be reduced.
In the above-described air-conditioning-apparatus cabinet according to the first aspect of the present invention, the peripheral-edge reinforcing ribs are formed in a radiating pattern from the attachment sections.
Each of the peripheral-edge reinforcing ribs is formed in a radiating pattern from each of the attachment sections. Thus, the edge portions of the reinforcing ribs are disposed in a radiating pattern from each of the attachment sections. Thus, the edge portions of the peripheral-edge reinforcing ribs, having high flexural strength, are provided on the top panel in the directions in which deformation tends to be caused due to the downward loads. Therefore, the deformation of the top panel can be reduced.
In the above-described air-conditioning-apparatus cabinet according to the first aspect of the present invention, the peripheral-edge reinforcing ribs are formed in spiral shapes around the attachment sections so as to swirl in the same directions as swirling directions of airflows generated by the air blowers.
The peripheral-edge reinforcing ribs are formed in spiral shapes so as to swirl in the same directions as the swirling directions of airflows generated by the air blowers. Thus, the airflows generated by the air blowers are less disturbed by the peripheral-edge reinforcing ribs. Therefore, noise is unlikely to be produced by turbulent airflows.
In the above-described air-conditioning-apparatus cabinet according to the first aspect of the present invention, at least one of the peripheral-edge reinforcing ribs is formed in a complicated shape having a plurality of flexural portions in cross section in the extending direction thereof.
At least one of the peripheral-edge reinforcing ribs is formed in a complicated shape having a plurality of flexural portions in cross section in the extending direction thereof. Thus, the second moment of area of the peripheral-edge reinforcing rib is further increased. Thus, the strength of the top panel can be increased. Therefore, the deformation of the top panel can be reduced.
According to a second aspect, the present invention provides an air conditioning apparatus including any of the above-described air-conditioning-apparatus cabinets to be embedded in a ceiling.
The air-conditioning-apparatus cabinet capable of reducing the deformation of the portion of the top panel between the air blowers is used. Thus, the deformation of the air-conditioning-apparatus cabinet of the air conditioning apparatus can be suppressed. Therefore, noise from the air conditioning apparatus resulting from the deformation of the air-conditioning-apparatus cabinet can be reduced. Advantageous Effects of Invention
The central reinforcing ribs are provided so as to extend in the direction perpendicular to an imaginary straight line connecting the attachment sections provided on the top panel. Thus, by attaching the air blowers to the undersurface of the top panel, even when the downward loads thereof are exerted on the attachment sections to cause downward deformation of the portion of the top panel between the air blowers, the downward loads exerted on the vicinities of the attachment sections can be distributed over the entire top panel via the central reinforcing ribs to support the air blowers. Therefore, it is possible to reduce the downward loads exerted on the vicinities of the attachment sections and to reduce the deformation of the portion of the top panel between the air blowers.

Brief Description of Drawings

{Fig. 1} Fig. 1 is a longitudinal sectional view of the structure of an air conditioning apparatus according to a first embodiment of the present invention.
(Fig. 2} Fig. 2 is a perspective view of an air-conditioning-apparatus cabinet of the air conditioning apparatus shown in Fig. 1.
{Fig. 3} Fig. 3 is a plan view of the air-conditioning-apparatus cabinet of the air conditioning apparatus shown in Fig. 1.
{Fig. 4} Fig. 4 is a view showing, by using contour lines, the amount of deformation of the air-conditioning-apparatus cabinet caused when air blowers are attached to a top panel of the air-conditioning-apparatus cabinet of the air conditioning apparatus shown in Fig. 1.

Description of Embodiments

First Embodiment

A first embodiment of the present invention will be described below with reference to Figs. 1 to 4.
As shown in Fig. 1, an air conditioning apparatus 1 of this embodiment includes an indoor unit 2 that is embedded in an opening (not shown) provided in the ceiling; and an outdoor unit (not shown) that is installed outside. The indoor unit 2 and the outdoor unit are connected via a refrigerant circuit (not shown), and heat is exchanged between the indoor unit 2 and the outdoor unit via the refrigerant circuit.
The indoor unit 2 includes an air-conditioning-apparatus cabinet 11 that is embedded in the opening provided in the ceiling; and a face panel (not shown) that covers the opening in the ceiling and also the air-conditioning-apparatus cabinet 11. Air inlet ports (not shown) and air outlet ports (not shown) are provided in the face panel.
The air-conditioning-apparatus cabinet 11 is provided with a plurality of (for example, two) air blowers 12 that take in indoor air from the air inlet ports in the face panel and deliver the indoor air from the air outlet ports to the room again; and a heat exchanger 13 that performs heat exchange between the indoor air taken in to the air-conditioning-apparatus cabinet 11 by the air blowers 12a and 12b and a refrigerant in the refrigerant circuit.
The air blowers 12 include fan motors 16 that are suspended in the air-conditioning-apparatus cabinet 11 with their drive shafts 14 facing substantially vertically downward; and centrifugal fans 17 (sirocco fans) that are provided below the fan motors 16 and driven by the fan motors 16.
The centrifugal fans 17 include multiblade fan main bodies 18 that are substantially coaxially mounted to the drive shafts 14 of the fan motors 16; and housings 19 that are provided so as to surround the fan main bodies 18 to form flow paths for guiding indoor air to areas surrounding the fan main bodies 18. Each of the centrifugal fans 17 has a configuration in which the fan main body 18 is rotationally driven by the corresponding fan motor 16, thereby suctioning indoor air from below the fan main body 18 through the air inlet ports in the face panel and delivering this indoor air toward the radially outer side of the fan main body 18 (that is, the peripheral edge of the air-conditioning-apparatus cabinet 11) to blow out the indoor air into the room through the air outlet ports in the face panel.
The heat exchanger 13 is provided between the air blowers 12a and 12b and a side panel 22, to be described later, and is disposed above a drain pan 20 so as to surround the air blower, 12a and the air blower 12b. The heat exchanger 13 performs heat exchange between the indoor air delivered by the air blowers 12a and 12b toward the radially outer sides of the fan main bodies 18a and 18b and the refrigerant in the refrigerant circuit.
The air-conditioning-apparatus cabinet 11 has a rectangular top panel 21 to which the air blowers 12a and 12b are attached on the undersurface thereof; and the side panel 22 that extends downward from the peripheral edge of the top panel 21 to surround a space formed below the top panel 21.
The air blowers 12a and 12b are attached to the undersurface of the top panel 21 via attachment sections 24a and 24b. The top panel 21 is formed by three dimensionally pressing a single metal plate. In this embodiment, the top panel 21 is formed in a rectangular shape with a length of 750 mm and a width of 1500 mm and is formed of a metal plate made from sheet steel with a plate thickness of 0.8 mm.
The attachment sections 24a and 24b, provided on the undersurface of the top panel 21, are disposed approximately at positions corresponding respectively, to one-third and two-thirds of the longitudinal distance of the top panel 21 from the side panel 22 (in Fig. 1, approximately at positions corresponding to one-third and two-thirds of the longitudinal distance of the top panel 21 from the side panel 22 from the left side toward the right side.
In this embodiment, the attachment sections 24a and 24b, provided on the undersurface of the top panel 21, are formed of approximately equilateral-triangle raised portions (not shown) that are convex downward from the top panel 21. The attachment sections 24a and 24b are each secured to the top panel 21 with three attaching bolts (not shown) that are disposed around the attachment sections 24a and 24b at approximately regular intervals.
Central reinforcing ribs 25 that extend in the direction perpendicular to an imaginary straight line (not shown) connecting the attachment section 24a and the attachment section 24b are formed on the top panel 21 between the attachment section 24a and the attachment section 24b. Furthermore, a plurality of peripheral-edge reinforcing ribs 23 are formed on the top panel 21 from the vicinity of each of the attachment sections 24a and 24b toward the peripheral edge.
The plurality of (for example, three) central reinforcing ribs 25 are provided on the top panel 21 between the attachment section 24a and the attachment section 24b. As shown in Fig. 1, in the central reinforcing ribs 25, edge portions 26 are tilted at an angle from the top panel 21, and regions surrounded by the edge portions 26 are flat and approximately parallel to the top panel 21. Specifically, each of the central reinforcing ribs 25 has an approximately trapezoidal shape in cross section perpendicular to the extending direction thereof. The central reinforcing ribs 25, which extend on the top panel 21 between the attachment section 24a and the attachment section 24b from one side close to the peripheral edge to the other side (in Fig. 1, from the peripheral edge on the lower side toward the peripheral edge on the upper side), have an approximately uniform width in the extending direction thereof.
As shown in Figs. 2 and 3, the peripheral-edge reinforcing ribs 23 are gradually increased in width from the attachment section 24a or 24b, provided on the top panel 21, toward the peripheral edge. End portions of the peripheral-edge reinforcing ribs 23 closer to the attachment section 24a are connected to each other. Furthermore, end portions of the peripheral-edge reinforcing ribs 23 closer to the attachment section 24b are similarly connected to each other. Thus, the entire circumference of each of the attachment sections 24a and 24b is surrounded by the plurality of the peripheral-edge reinforcing ribs 23. Specifically, the peripheral-edge reinforcing ribs 23 are formed in a radiating pattern from each of the attachment sections 24a and 24b.
As shown in Fig. 1, in the peripheral-edge reinforcing ribs 23, edge portions 26 are tilted at an angle from the top panel 21, and regions surrounded by the edge portions 26 are flat and approximately parallel to the top panel 21. Specifically, each of the peripheral-edge reinforcing ribs 23 has an approximately trapezoidal shape in cross section perpendicular to the extending direction thereof. The widths of the peripheral-edge reinforcing ribs 23 (the widths in the circumferential direction from each of the attachment sections 24a and 24b) are gradually increased from each of the attachment sections 24a and 24b toward the peripheral edge.
In the thus-structured air conditioning apparatus 1, by providing the central reinforcing ribs 25 on the top panel 21 between the attachment section 24a and the attachment section 24b of the air-conditioning-apparatus cabinet 11 of the indoor unit, the downward loads of the air blowers 12a and 12b exerted on the attachment section 24a and the attachment section 24b can be distributed over the entire top panel 21 via the central reinforcing ribs 25 to support the air blowers 12a and 12b. Furthermore, by forming the plurality of peripheral-edge reinforcing ribs 23 in a radiating pattern from each of the attachment sections 24a and 24b toward the peripheral edge, the downward loads of the air blowers 12a and 12b exerted on the attachment sections 24a and 24b can also be distributed over the peripheral edge of the top panel 21 via the peripheral-edge reinforcing ribs 23 to support the air blowers 12a and 12b.
Since the downward loads of the air blowers 12a and 12b exerted on the attachment section 24a and the attachment section 24b are distributed over the top panel 21 via the central reinforcing ribs 25 and the peripheral-edge reinforcing ribs 23 to support the air blowers 12a and 12b, the loads exerted on the attachment section 24a and the attachment section 24b can be received by the entire top panel 21. Therefore, downward deformation of the top panel 21, which is caused when the downward loads are received by the portion of the top panel 21 between the attachment section 24a and the attachment section 24b and by the portions of the top panel 21 in the vicinities of the attachment section 24a and the attachment section 24b, is reduced.
The edge portions 26 of the peripheral-edge reinforcing ribs 23 and those of the central reinforcing ribs 25 form flexural portions that are flexed in directions intersecting with the undersurface of the top panel 21. Thus, the second moment of area is large in the cross sections perpendicular to the extending directions of the ribs.
Thus, since the edge portions 26 of the central reinforcing ribs 25, having high flexural strength, are provided in the direction in which deformation is caused on the portion of the top panel 21 between the attachment section 24a and the attachment section 24b due to the downward loads of the air blowers, 12a and 12b, attached to the attachment sections 24a and 24b, respectively, the deformation of the portion of the top panel 21 between the attachment section 24a and the attachment section 24b is reduced.
Furthermore, the peripheral-edge reinforcing ribs 23, whose individual widths are increased toward the peripheral edge, are formed in a radiating pattern from each of the attachment sections 24a and 24b. Thus, the edge portions of the peripheral-edge reinforcing ribs 23 are disposed in a radiating pattern from each of the attachment sections 24a and 24b. Specifically, since the edge portions 26 of the peripheral-edge reinforcing ribs 23, having high flexural strength, are provided on the top panel 21 in the directions in which deformation tends to be caused due to the loads, the deformation of the top panel 21 is reduced.
The amount of deformation of the top panel 21 caused when the air blowers 12a and 12b (fan motors with a weight of about 2.3 kg and centrifugal fans with a weight of slightly over 0.8 kg: giving a total weight of slightly over 3.1 kg) are attached to the top panel 21 of the thus-structured air-conditioning-apparatus cabinet 11 is calculated through numerical analysis.
Fig. 4 is a view showing, by using contour lines, the amount of deformation of the top panel 21 caused when the two air blowers, 14a and 14b are attached to the single top panel 21. The vertical displacement of the top panel 21 between adjacent contour lines is 0.1 mm.
In the air-conditioning-apparatus cabinet 11 of this embodiment, in which the three central reinforcing ribs 25 are formed on the top panel 21 between the attachment section 24a and the attachment section 24b in the longitudinal direction of the top panel 21, and the plurality of peripheral-edge reinforcing ribs 23, whose individual widths are gradually increased from each of the attachment sections 24a and 24b toward the peripheral edge, are formed in a radiating pattern from each of the attachment sections 24a and 24b, it is found that the lowermost portions on the top panel 21 are located in the vicinities of the attachment sections 24a and 24b but are not located between the attachment section 24a and the attachment section 24b. Specifically, the portion of the top panel 21 between the attachment section 24a and the attachment section 24b is displaced downward from the peripheral edge by 0.6 mm, but the most-displaced portion located in the vicinity of the attachment section 24b is displaced downward from the peripheral edge by 0.9 mm. Therefore, the displacement of the portion of the top panel 21 between the attachment section 24a and the attachment section 24b is smaller than the displacement of the portion in the vicinity of the attachment section 24b.
In this way, by providing the central reinforcing ribs 25 on the top panel 21 between the attachment section 24a and the attachment section 24b, it is possible to suppress the deformation of the portion of the top panel 21 between the attachment section 24a and the attachment section 24b without increasing the plate thickness of the top panel 21.
As described above, according to the air-conditioning-apparatus cabinet and the air conditioning apparatus having the same of this embodiment, the following advantages are afforded.
The central reinforcing ribs 25 are provided so as to extend in the direction perpendicular to an imaginary straight line connecting the attachment section 24a and the attachment section 24b, which are provided on the top panel 21. Thus, by attaching the air blowers 12a and 12b to the undersurface of the top panel 21, even when the downward loads thereof are exerted on the attachment sections 24a and 24b to cause downward deformation of the portion of the top panel 21 between the air blower 12a and the air blower 12b, the downward loads exerted on the vicinities of the attachment sections 24a and 24b can be distributed over the entire top panel 21 via the central reinforcing ribs 25 to support the air blowers 12a and 12b. Therefore, the deformation of the portion of the top panel 21 between the air blower 12a and the air blower 12b can be reduced.
The three (plurality of) central reinforcing ribs 25 are provided on the top panel 21 between the air blower 12a and the air blower 12b. Thus, by attaching the air blower 12a and the air blower 12b to the undersurface of the top panel 21, even when the downward loads thereof are exerted on the attachment sections 24a and 24b to cause downward deformation of the portion of the top panel 21 between the air blower 12a and the air blower 12b, the downward loads exerted on the vicinities of the attachment sections 24a and 24b can be distributed over the entire top panel 21 via the three central reinforcing ribs 25 to support the air blowers 12a and 12b. Therefore, the deformation of the portion of the top panel 21 between the air blower 12a and the air blower 12b can be reduce.
The peripheral-edge reinforcing ribs 23, whose individual widths gradually increased from each of the attachment sections 24a and 24b toward the peripheral edge (widths in the circumferential direction from each of the attachment sections 24a and 24b), are provided in the vicinities of the attachment sections 24a and 24b. Thus, even when the downward loads are exerted on the attachment sections 24a and 24b, the downward loads on the vicinities of the attachment sections 24a and 24b can be distributed over the peripheral edge via the peripheral-edge reinforcing ribs 23. Thus, the downward loads exerted on the vicinities of the attachment sections 24a and 24b can be distributed over the entire top panel 21 via the peripheral-edge reinforcing ribs 23 to support the air blowers 12a and 12b. Therefore, the deformation of the top panel 21 can be reduced.
The peripheral-edge reinforcing ribs 23 are formed in a radiating pattern from each of the attachment sections 24a and 24b. Thus, the edge portions 26 of the peripheral-edge reinforcing ribs 23 are disposed in a radiating pattern from each of the attachment sections 24a and 24b. Thus, the edge portions 26 of the peripheral-edge reinforcing ribs 23, having high flexural strength, are provided on the top panel 21 in the directions in which deformation tends to be caused due to the downward loads. Therefore, the deformation of the top panel 21 can be reduced.
The air-conditioning-apparatus cabinet 11, which is capable of reducing the deformation of the portion of the top panel 21 between the air blower 12a and the air blower 12b, is used. Thus, the deformation of the air-conditioning-apparatus cabinet 11 of the air conditioning apparatus 1 can be suppressed. Therefore, noise from the air conditioning apparatus 1 resulting from the deformation of the air-conditioning-apparatus cabinet 11 can be reduced.
In this embodiment, a description has been given of a case where the central reinforcing ribs 25 and the peripheral-edge reinforcing ribs 23 are formed in approximately trapezoidal shapes in cross sections perpendicular to the respective extending directions thereof. However, the present invention is not limited thereto, and the shapes of the central reinforcing ribs 25 and the peripheral-edge reinforcing ribs 23 in cross sections perpendicular to the respective extending directions thereof may be any desired shapes, such as arcs, triangles, and rectangles.
Furthermore, in this embodiment, a description has been given of a case where the two air blowers 12a and 12b are provided in the indoor unit 2. However, the present invention is not limited thereto, and two or more air blowers 12 may be provided therein.
Furthermore, in this embodiment, a description has been given of a case where the three central reinforcing ribs 25 are formed on the top panel 21 between the attachment section 24a and the attachment section 24b. However, the present invention is not limited thereto, and the number of central reinforcing ribs 25 may be one or more.
In this embodiment, a description has been given of a case where the edge portions 26 of the peripheral-edge reinforcing ribs 23 are tilted at an angle from the top panel 21, and regions surrounded by the edge portions 26 of the peripheral-edge reinforcing ribs 23 are flat and approximately parallel to the top panel 21. However, the present invention is not limited thereto, and at least one of the peripheral-edge reinforcing ribs 23 may be formed in a complicated shape having a plurality of flexural portions in cross section in the extending direction thereof.
By forming the peripheral-edge reinforcing rib 23 in the complicated shape in this wary, the second moment of area of the peripheral-edge reinforcing rib 23 is further increased, so that the strength of the top panel 21 is increased, and the deformation of the top panel 21 is reduced.

Second Embodiment

An air conditioning apparatus according to this embodiment differs from that of the first embodiment in that peripheral-edge reinforcing ribs are formed in spiral shapes around attachment sections so as to swirl in the same directions as the swirling directions of airflows generated by the air blowers. The other structures are the same as those of the first embodiment. Therefore, identical reference symbols are assigned to the same structural parts, and a description thereof will be omitted.
The peripheral-edge reinforcing ribs provided on the top panel have spiral shapes around the attachment sections so as to swirl in the same directions as the swirling directions of airflows generated by the centrifugal fans of the air blowers.
In the air conditioning apparatus having the top panel provided with those spiral-shaped peripheral-edge reinforcing ribs, airflows generated by the air blowers are less disturbed by the peripheral-edge reinforcing ribs. Thus, it is possible to reduce noise produced when the airflows generated by the air blowers are disturbed.
As described above, according to the air-conditioning-apparatus cabinet and the air conditioning apparatus having the same of this embodiment, the following advantage is afforded.
The peripheral-edge reinforcing ribs are formed in spiral shapes so as to swirl in the same directions as the swirling directions of airflows generated by the air blower. Thus, the airflows generated by the air blowers are less disturbed by the peripheral-edge reinforcing ribs. Therefore, noise is unlikely to be produced by turbulent airflow.

{Reference Signs List}

1: air conditioning apparatus
11: air-conditioning-apparatus cabinet
21: top panel
22: side panel
24a, 24b: attachment sections
25: central reinforcing ribs

Claims

An air-conditioning-apparatus cabinet comprising:
a top panel to which a plurality of air blowers are attached on an undersurface thereof via attachment sections;

a side panel that extends downward from a peripheral edge of the top panel to surround a space below the top panel; and

a central reinforcing rib that extends in a direction perpendicular to an imaginary straight line connecting the attachment sections.
An air-conditioning-apparatus cabinet according to claim 1, wherein a plurality of the central reinforcing ribs are provided.
An air-conditioning-apparatus cabinet according to claim 1 or 2, further comprising, in vicinities of the attachment sections, a plurality of peripheral-edge reinforcing ribs whose individual widths are gradually increased from the vicinities of the attachment sections toward the peripheral edge.
An air-conditioning-apparatus cabinet according to any one of claims 1 to 3, wherein the peripheral-edge reinforcing ribs are formed in a radiating pattern from the attachment sections.
An air-conditioning-apparatus cabinet according to any one of claims 1 to 4, wherein the peripheral-edge reinforcing ribs are formed in spiral shapes around the attachment sections so as to swirl in the same directions as swirling directions of airflows generated by the air blowers.
An air-conditioning-apparatus cabinet according to any one of claims 1 to 5, wherein at least one of the peripheral-edge reinforcing ribs is formed in a complicated shape having a plurality of flexural portions in cross section in the extending direction thereof.
An air conditioning apparatus comprising an air-conditioning-apparatus cabinet to be embedded in a ceiling, according to any one of claims 1 to 6.