GB2314924A

GB2314924A - Ceiling attachment type air conditioner

Info

Publication number: GB2314924A
Application number: GB9714041A
Authority: GB
Inventors: Makoto Watanabe; Kenji Gajina
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 1996-07-03
Filing date: 1997-07-02
Publication date: 1998-01-14
Anticipated expiration: 2017-07-02
Also published as: JPH1019370A; GB2314924B; KR100238512B1; JP3593418B2; KR980010169A; GB9714041D0

Abstract

A ceiling attachment type air conditioner comprises a casing (20) having a lower opening, a wind fan (21) arranged centrally in the casing (20), a heat exchanger (25) disposed along a periphery of the wind fan (21), a drain pan (23) disposed below the heat exchanger, a plurality of discharge ports (24) formed in peripheral portions of the drain pan (23), a bell mouth (27) disposed below the wind fan (21) and forming a suction port of the wind fan (21), the bell mouth (27) and the drain pan (23) cooperating in separating, in an airtight manner, a primary side and secondary side of the wind fan (21) from each other, a receiving space portion formed integral with a lower portion of the bell mouth (27) and bent in the form of a U-shape when viewed in plan view, and an electric component box (28) located in the receiving space portion and U-shaped when viewed in plan view.

Description

CEILING ATTACHMENT TYPE AIR CONDITIONER This invention relates to an air conditioner with a ceiling attachment type indoor unit.

Figs. lOa, lOb and 11 of the accompanying drawings show a conventional ceiling attachment type air conditioner (indoor unit).

A casing 1 incorporated in the air conditioner is of an octagonal shape when viewed in plan view, and has an upper surface wall, a peripheral wall and a lower opening.

A wind fan 2 is disposed at a substantial center portion of the upper surface wall of the casing 1. The wind fan 2 is of a so-called scirocco fan type, which is disposed to suck air from below and discharge the same through circumferential portions thereof.

A bell mouth 3 is connected to the lower side of the wind fan 2 and forms an air inlet port for the wind fan. The bell mouth adjusts the flow of air introduced into the fan.

A heat exchanger 4, which is of a substantially rectangular shape without one corner when viewed in plan view, is provided in a space defined by the periphery of the wind fan 2 and the peripheral wall of the casing 1. In other words, the periphery of the wind fan 2 is substantially surrounded with the heat exchanger 4.

The heat exchanger 4 is supported by a drain pan 5, which has its outer periphery fitted in the lower opening of the casing 1 and its inner periphery separated from the inner periphery of the heat exchanger 4 by a predetermined distance.

A plurality of discharge ports 6 are formed in outer peripheral portions of the drain pan 5 along the inner surfaces of lengthwise and widthwise sides of the casing 1 but not along oblique sides thereof. A lower end portion of the bell mouth 3 is located inside the inner periphery of the drain pan 5 with a predetermined space interposed therebetween.

A bell mouth attachment plate 7 is fitted in a space defined between the inner periphery of the drain pan 5 and the outer peripheral surface of the lower end portion of the bell mouth 3.

The bell mouth 3 and an electric component box 8 are attached to the bell mouth attachment plate 7.

The electric component box 8 contains electric components necessary for drive control of the wind fan 2 and for transmission of a signal from a temperature sensor to a control unit (both of which are not shown).

In the above-described structure, the primary side (sucking side) of the wind fan 2 is separated from the secondary side (discharge side) of the fan by means of the bell mouth attachment plate 7 and the drain pan 5.

This also means that the air suction side passage of the heat exchanger 4 is separated from the air discharge side passage of the same by means of the bell mouth attachment plate 7 and the drain pan 5.

An electric heater 9 used as an auxiliary heater at the time of heating the room is provided on the inner surface of the upper surface wall of the casing 1 substantially directly above the electric component box 8.

A face panel 10 is fitted in the lower opening of the casing 1 below the drain pan 5, and projects from the ceiling plate S to the room R to be airconditioned. Panel discharge ports lOa which have the same shape and area as the discharge ports 6 open in those portions of the face panel 10 which correspond to the discharge ports 6.

Further, a panel suction port lOb, which has the same shape and area as a space defined by the inner periphery of the drain pan 5, is formed in that portion of the face panel 10 which is opposed to the space of the drain pan 5. A filter 11 is fitted in the panel suction port lOb and a grill 12 covers the suction port lOb.

A conventional ceiling attachment type air conditioner constructed as above has satisfactory air conditioning performance. However, this conditioner has the following disadvantages in structure: 1) The bell mouth attachment plate 7 is necessary in addition to the bell mouth 3 in order to adjust the flow of air, resulting in an increase in required cost.

2) The electric component box 8 must be made compact in order to secure the air suction area of the wind fan 2.

3) At the time of performing maintenance working of the electric heater 9 contained in the casing 1, it is necessary to detach the electric component box 8, the bell mouth 3 and the bell mouth attachment panel 7 after detaching the face panel 10, which means that a great deal of time and labor is required.

According to an aspect of the invention, there is provided a ceiling attachment type air conditioner comprising: a casing attached to a ceiling of a room to be air-conditioned and having a lower opening; a wind fan provided in the casing and including a fan for sucking air from below and circumferentially discharging the sucked air; a heat exchanger disposed along a periphery of the wind fan; a drain pan disposed below the heat exchanger; a plurality of discharge ports formed in peripheral portions of the drain pan; a bell mouth disposed below the wind fan for adjusting the flow of air sucked into the wind fan, the bell mouth and the drain pan cooperating in separating, in an airtight manner, a primary side and secondary side of the wind fan from each other; and an electric component box located in a space defined between the bell mouth and the drain pan.

Certain embodiments of the invention can thus provide a ceiling attachment type air conditioner constituted of a reduced number of components and hence showing a lower resistance against ventilation, having a larger space for receiving an electric component box and/or facilitating maintenance work of an electric heater incorporated therein.

Further aspects of the invention and exemplified by the attached claims.

For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Fig. 1 is an exploded perspective view, showing a ceiling attachment type air conditioner according to a first embodiment; Fig. 2A is a schematic sectional view, showing the ceiling attachment type air conditioner of Fig. 1; Fig. 2B is a plan view, showing the air conditioner of Fig. 1 which is in a state assumed when a face panel incorporated therein is detached; Fig. 3A is a section view, showing the ceiling attachment type air conditioner of Fig. 1 which is in a state assumed when a bell mouth and an electric component box incorporated therein are detached; Fig. 3B is a plan view, showing the air conditioner of Fig. 3A; Fig. 4 is a schematic sectional view, showing an air conditioner according to a second embodiment, which is in a state assumed when a face panel incorporated therein is detached; Fig. 5 is a perspective view, showing an electric component box incorporated in the air conditioner of Fig. 4; Fig. 6 is an exploded perspective view, showing a ceiling attachment type air conditioner according to a third embodiment; FIG. 7 is a schematic sectional view, showing the ceiling attachment type air conditioner of the third embodiment; FIG. 8 is a schematic plan view, showing the air conditioner of the third embodiment, which is in a state assumed when a face panel incorporated therein is detached; FIG. 9A is a schematic plan view, showing an air conditioner according to a fourth embodiment, which is in a state assumed when a face panel incorporated therein is detached; FIG. 9B is a schematic plan view, showing an air conditioner of a fifth embodiment, which is in a state assumed when a face panel incorporated therein is detached; FIG. 9C is a schematic plan view, showing an air conditioner of a sixth embodiment, which is in a state assumed when a face panel incorporated therein is detached; FIG. 9D is a schematic plan view, showing an air conditioner of a seventh embodiment, which is in a state assumed when a face panel incorporated therein is detached; FIG. lOA is a schematic plan view, showing a conventional ceiling attachment type air conditioner which is in a state assumed when a face panel incorporated therein is detached; Fig. lOB is a schematic sectional view, showing the conventional ceiling attachment type air conditioner; and Fig. 11 is a schematic plan view, showing the conventional air conditioner, which is in a state assumed when an attachment panel, a bell mouth and an electric component box incorporated therein are detached.

First, a first embodiment will be described with reference to Figs. 1-3.

A casing 20 incorporated in the air conditioner is of an octagonal shape when viewed in plan view, and has an upper surface wall 20a, a peripheral wall 20b and a lower opening.

The casing 20 is attached to a ceiling plate S such that the lower opening thereof opens through an opening formed in the ceiling plate S.

A fan motor 21a which constitutes a wind fan 21 is fixed on the upper surface wall 20a of the casing 20.

The fan motor 21a has a downwardly and vertically projecting rotary shaft. A fan 21b is fitted on the rotary shaft of the motor 21a. The fan 21b is of a so-called scirocco fan type, which is disposed to suck air from below and discharge the same through a circumferential portion thereof.

As is shown, in particular, in FIGS. 2B and 3B, the center Ob of the wind fan 21 is deviated from the center Oa of the casing 20.

Further, a heat insulating member 22 shown only in FIG. 1 is attached in a tight manner, by means of, for example, an adhesive, to the inner surface of substantially the entire peripheral wall 20b of the casing 20 except for a lower portion thereof, and also to the inner surface of an edge portion of the upper surface wall 20a of the casing 20.

An octagonal drain pan 23 with an outer diameter identical to that of the heat insulating member 22 is attached to the inner surface of the peripheral wall 20b of the casing 20 in a tight manner such that it is connected to the lower end of the heat insulating member 22.

The drain pan 23 has a plurality of discharge ports 24 formed therein along lengthwise and widthwise sides thereof but not along oblique sides thereof.

An attachment hole 26 with a partially circular and partially linear outline is formed in substantially a center portion of the drain pan 23.

That portion of the drain pan 23 which is located between the discharge ports 24 and the attachment hole 26 has a U-shaped cross section and holds therein a heat exchanger 25. In other words, a lower end portion of the heat exchanger 25 is placed in the above portion of the drain pan 23, while an upper end portion of the heat exchanger 25 is in contact with the inner surface of the upper surface wall 20a of the casing 20.

Thus, the heat exchanger 25 is interposed between the casing 20 and the drain pan 23.

More specifically, the heat exchanger 25 is disposed outside the wind fan 21 and inside the discharge ports 24, and has a rectangular shape without one corner when viewed in plan view. The heat exchanger 25 is connected to an outdoor unit (not shown), thereby constituting a refrigeration cycle.

A bell mouth 27, which comprises a main body 27A and a receiving space member 27B, has a lower end portion thereof fitted in the attachment hole 26 of the drain pan 23.

The bell mouth main body 27A has a circular upper end portion coupled with a suction portion which constitutes a lower end portion of the wind fan 21.

The main body 27A is inclined downwardly and outwardly from the upper end portion to a lower end portion, which has a partially circular and partially linear outline and is fitted in the attachment hole 26.

The receiving space member 27B is formed integral with a lower linear portion of the bell mouth main body 27A, and defines a space for receiving an electric component box 28 which will be referred to later.

The receiving space member 27B is substantially U-shaped in plan view, and has its side portions outwardly inclined.

Inner portions of the side portions of the receiving space member 27B obliquely incline to the axis Ob of the wind fan 21b. An inner portion of the member 27B between the side portions constitutes a vertical wall having the same height as a corresponding linear portion of the bell mouth main body 27A.

The electric component box 28 is substantially U-shaped when viewed in plan view, which is identical to the shape of the receiving space member 27B. The thickness (height) of the box is identical to that of the vertical wall of the receiving space member 27B, and hence is used for positioning.

The electric component box 28 is secured to the receiving space member 27B by means of appropriate means. The box 28 contains electric components necessary to control the wind fan 21, and to supply a control unit (not shown) with a signal output from a temperature sensor (not shown).

As is shown in FIG. 2B, the attachment position of the electric component box 28 is deviated from the center Oa of the casing 20 in a direction opposite to the center Ob of the wind fan 21.

When the wind fan 21 is driven, air is sucked into the fan through the lower opening of the ball mount main body 27A. In other words, the lower opening of the body 27A serves as a suction port.

The primary side (sucking side) of the wind fan 21 is separated from the secondary side (discharge side) of the fan by means of the bell mouth 27 and the drain pan 23. Concerning the heat exchanger 25, its air suction side passage M is separated from its air discharge side passage N.

The casing 20 contains an electric heater 29 used as an auxiliary heater at the time of heating a room R to be conditioned. The position of the heater 29 corresponds to that of the electric component box 28.

As is shown in FIG. 2A only, a face panel 30 is fitted in the lower opening of the casing 20 such that it is exposed to the room. Panel discharge ports 30a having the same shape and area as the discharge ports 24 are formed in the panel 30, opposed to the discharge ports 24.

A panel suction port 30b having the same shape and area as an opening formed in a central portion of the drain pan 23 is formed in the face panel 30, opposed to the opening. A filter 31 is fitted in the panel suction port 30b, and covered with a grill 32.

When the wind fan 21 of the ceiling attachment type air conditioner constructed as above is driven to start its refrigeration cycle operation, the air in the to-be-conditioned room R is sucked into the casing 20 through the panel suction port 30b of the face panel 30 via the grill 32 and the filter 31.

The air having its flow adjusted by the bell mouth 27 is guided to the heat exchanger 25 via the wind fan 21, where heat exchange is performed between the air and a refrigerant supplied therein. The heatexchanged air is discharged to the to-be-conditioned room through the discharge ports 24 formed in circumferential portions of the drain pan 23 and the panel discharge ports 30a of the face panel 30.

Since the bell mouth main body 27A of the bell mouth 27 interposed between the attachment hole 26 of the drain pan 23 and the lower end of the wind fan 21 is tapered from its lower end to its upper end, the flow of air can be adjusted at high efficiency.

Further, since the center Ob of the wind fan 21 is deviated from the center Oa of the casing 20, and the electric component box 28 is situated in a position opposite to that of the center Ob of the wind fan 21 with respect to the center Oa, a large area for disposing the electric component box 28 can be secured without changing the capacity of the casing 20.

Moreover, at the time of performing maintenance working of the electric heater 29 contained in the casing 20, the face panel 30 is detached to expose the drain pan 23, the bell mouth 27 and the electric component box 28, thereby detaching the box 28 and the bell mouth 27. The drain pan 23 is maintained as it is, as is shown in FIGS. 3A and 3B. Since in this state, the electric heater 29 is exposed between the inside opening of the drain pan 23 and the wind fan 21, it can be detached through the space between the pan 23 and the fan 21 as indicated by the arrow in FIG. 3A.

Since in other words, the electric component box 28 is attached to the bell mouth 27, the electric heater 29 can be exposed by detaching substantially only the bell mouth 27. This facilitates maintenance working.

The invention may be modified, as a second embodiment, as shown in FIGS. 4 and 5.

An electric component box 28A incorporated therein is U-shaped, and has an inner lower portion with an inclined surface a. The inclined surface a is gradually outwardly inclined from its upper end to its lower end.

On the other hand, the main body 27A of the bell mouth 27 is gradually outwardly inclined from its upper end to its lower end as in the first embodiment.

Accordingly, in the state shown in FIG. 4 in which the electric component box 28A is attached, sucked air is more efficiently and smoothly guided into the casing by means of the bell mouth 27 and the electric component box 28A when the wind fan 21 is driven, thereby reducing the resistance of the air and hence increasing the effect of flow adjustment of the air.

Referring then to FIGS. 6 - 8, a third embodiment will be described. The basic structure of a ceiling attachment type air conditioner according to the third embodiment is similar to that of the first or second embodiment.

As is shown in FIG. 6, the third embodiment comprises a casing 20A, a wind fan 21 and a heat exchanger 25A contained in the casing, a drain pan 23A fitted in the lower opening of the casing 20A and supporting the heat exchanger 25A, a face panel 30, and a heat insulating member 22A attached to part of the inner surface of the casing 20A (a bell mouth incorporated therein is not shown).

The reason why the casing, the heat insulating member, the drain pan and the heat exchanger are denoted by reference numerals 20A, 22A, 23A, and 25A which differ from the reference numerals denoting corresponding structural elements in the first or second embodiment is that they have features peculiar thereto as will be described later. The other structural elements, which are substantially identical to those employed in the first or second embodiment, are denoted by corresponding reference numerals, and no detailed description will be given thereof.

An outside air inlet hole 35 is formed in the peripheral wall 20b of the casing 20A, through which hole an outside air duct 36 having an end thereof attached to an outer surface portion of the peripheral wall 20b communicates with the interior of the casing 20A.

The other end of the outside air duct 36 is connected to an outside air inlet port (not shown) formed in a wall of a house for taking in outside air.

The outside air inlet port formed in the wall is provided with a shutter mechanism (not shown) to be opened and closed by remote control from the inside of the room.

A guide hole 36a is formed in a peripheral wall 22a included in the heat insulating member 22A, and communicates with the outside air inlet hole 35 of the casing peripheral wall 20b. An expansion aiding wall 37 projects from the inner surface of that portion of the peripheral wall 22a of the heat insulating member, in which the guide hole 36a is formed, thereby defining a rectangular space between the wall 37 and the peripheral wall 22a.

The upper surface wall 22b of the heat insulating member 22A defines the upper end of the rectangular space between the expansion aiding wall 37 and the peripheral wall 22a of the heat insulating member 22A.

Further, the rectangular space opens toward one of the ports 30a of the face panel 30. The passage formed by the guide hole 36a and the rectangular space will be referred to as an "outside air intake passage 38".

An outside air intake passage 39 having the same shape as the outside air intake passage 38 of the heat insulating member 22A is formed through a corresponding portion of the drain pan 23A.

Thus, the outside air intake passage 38 of the heat insulating member 22A communicates with the outside air intake passage 39 of the drain pan 23A.

A lower portion of the outside air intake passage 39 is opposed to the face panel 30 with a predetermined gap defined therebetween for permitting air passing.

As is shown in FIGS. 6 and 8, the heat exchanger 25A comprises a pair of heat exchanger elements A, which are L-shaped when viewed in plan view, have their respective ends spaced from each other, and are disposed symmetrical to each other.

Those ends of the heat exchanger elements A which are close to the outside air intake passages 38 and 39 are coupled with each other by means of a shield plate 40. In other words, all the outside air discharged through the outside air intake passages 38 and 39 is introduced into the air suction side passage M, and prevented by the shield plate 40 from entering the air discharge side passage N through the space between the heat exchanger elements A.

The other ends of the heat exchanger elements A opposite to the ends coupled by the shield plate 40 are respectively in tight contact with a pair of projections b provided on inner peripheral wall portions of the heat insulating member 22A, thereby also preventing the outside air from entering the air discharge side passage N.

When the wind fan 21 of the ceiling attachment type air conditioner constructed as above is driven to start its refrigeration cycle operation, the air in the to-be-conditioned room R is sucked into the casing 20A through the panel suction port 30b of the face panel 30 via the grill 32 and the filter 31.

The air having its flow adjusted by a bell mouth (not shown) is guided to the heat exchanger 25A via the wind fan 21, where heat exchange is performed between the air and a refrigerant supplied therein. The heatexchanged air is discharged to the to-be-conditioned room R through the discharge ports 24 formed in circumferential portions of the drain pan 23A and the panel discharge ports 30a of the face panel 30.

If the shutter of the outside air duct 36 is opened, fresh outside air is introduced into the outside air inlet hole 35 through the duct, and flows through the outside air intake passages 38 and 39 of the heat insulating member 22A and the drain pan 23A.

When the outside air is discharged through the outside air intake passage 39 of the drain pan 23A, it is mixed with the air sucked from the to-beconditioned room R to the air suction side passage M through the suction port 30b of the face panel 30.

This air mixture is adjusted in flow by the bell mouth, then guided to the heat exchanger 25A via the wind fan 21, and discharged, after heat exchange, to the to-be-conditioned room R through the discharge ports 24 and the panel discharge ports 30a. Thus, the heat-exchanged air in the room contains outside fresh air.

Further, the shield plate 40 securely prevents fresh outside air guided in the outside air intake passages 38 and 39 from directly leaking from the air suction side passage M to the air discharge side passage N, thereby increasing the efficiency of heat exchange.

The outside air inlet hole 35 and the outside air intake passages 38, 39 can be provided by only partially modifying the casing 20A, the heat insulating member 22A or the drain pan 23A. This means that no dedicated chamber is necessary, and accordingly no time and labor for the attachment of such a chamber is required. As a result, the workability of the indoor unit is significantly enhanced, and the required cost is significantly reduced.

Seal mechanisms as shown in FIGS. 9A - 9D may be employed in place of the shield plate 40.

Referring first to FIG. 9A, an expansion aiding wall 37A forming the outside air intake passages 38 and 39 is an inwardly projecting thick wall. This wall has cutouts 41 engaged with end portions of the heat exchanger elements A.

Since the projecting wall of the expansion aiding wall 37A airtightly separates the air suction side passage M and the air discharge side passage N from each other, the shield plate 40 employed in the abovedescribed embodiment is not necessary.

A seal mechanism shown in FIG. 9B is basically similar to the FIG. 9A one in that an expansion aiding wall 37B includes an inwardly projecting thick wall and a pair of cutouts 41 engaged with end portions of the heat exchanger elements A, thereby airtightly separating the air suction side passage M and the air discharge side passage N from each other. However, the expansion aiding wall 37B differs in that it has side wall portions c extending perpendicular to side portions of the heat exchanger elements A, respectively.

Accordingly, even when part of the air guided through the heat exchanger 25A to the air discharge side passage N smashes against the expansion aiding wall 37B, no turbulence will occur since the side portions c of the wall 37B do not define such sharply edged spaces as those denoted by reference sign d in the FIG. 9A case. As a result, the noise of wind can be reduced.

In a seal mechanism shown in FIG. 9C, only side portions c of an expansion aiding wall 37C are formed thick. End portions of the heat exchanger elements A are engaged only with the side portions c of the wall 37C, thereby airtightly separating the air suction side passage M and the air discharge side passage N from each other. Also in this case, the side portions c of the expansion aiding wall 37C extend perpendicular to side portions of the heat exchanger elements A, respectively.

Accordingly, even when part of the air guided through the heat exchanger 25A to the air discharge side passage N smashes against the expansion aiding wall 37C, no turbulence will occur since the side portions c of the wall 37C do not define such sharply edged spaces as those denoted by reference sign d in the FIG. 9A case. As a result, the noise of wind can be reduced.

In a seal mechanism shown in FIG. 9D, the aforementioned shield plate 40 bridges end portions of the heat exchanger elements A and separates the air suction side passage M and the air discharge side passage N from each other.

In this case, however, there is provided an angle expansion aiding wall 37D which includes a face f arranged parallel to the shield plate 40 with a narrow gap interposed therebetween, and inclined faces e extending at an obtuse angle from the opposite ends of the face f, respectively.

Thus, the faces f and e of the expansion aiding wall 37D form part of the air discharge side passage N, which prevents turbulence of wind and contributes to its smooth flow and a reduction in the noise of the same.

Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept;

Claims

1. A ceiling attachment type air conditioner comprising: a casing attached to a ceiling of a room to be air-conditioned and having a lower opening; a wind fan provided in the casing and including a fan for sucking air from below and circumferentially discharging the sucked air; a heat exchanger disposed along a periphery of the wind fan; a drain pan disposed below the heat exchanger; a plurality of discharge ports formed in peripheral portions of the drain pan; a bell mouth disposed below the wind fan for adjusting the flow of air sucked into the wind fan, the bell mouth and the drain pan cooperating in separating, in an airtight manner, a primary side and secondary side of the wind fan from each other; and an electric component box located in a space defined between the bell mouth and the drain pan.

2. An air conditioner according to claim 1, wherein the bell mouth comprises: a bell mouth main body having an upper end thereof engaged with a suction portion as a lower portion of the wind fan, a lower end thereof engaged with an attachment hole formed in the drain pan, and a portion located between the upper and lower ends and tapered from the lower end to the upper end; and a receiving space portion formed integral with a side portion of the bell mouth main body, substantially U-shaped when viewed in plan view, and having opposite side portions outwardly inclined; and the electric component box is substantially U-shaped when viewed in plan view, and received in the receiving space portion.

3. An air conditioner according to claim 1 or 2, wherein the wind fan is positioned such that a center thereof is offset by a predetermined distance from a center of the casing in a direction opposite to a direction in which the electric component box is disposed.

4. An air conditioner according to claim 1, 2 or 3, wherein the electric component box has an inner surface, a lower portion of the inner surface being outwardly inclined to a lower end thereof.

5. An air-conditioner according to any one of the preceding claims and comprising an electric heater disposed in the casing above the electric component box.

6. A ceiling attachment type air conditioner comprising: a casing attached to a ceiling of a room to be air-conditioned and having a lower opening; a wind fan provided in the casing and including a fan for sucking air from below and circumferentially discharging the sucked air; a heat exchanger disposed along a periphery of the wind fan; a drain pan disposed below the heat exchanger; a plurality of discharge ports formed in peripheral portions of the drain pan; a bell mouth disposed below the wind fan for adjusting the flow of air sucked into the wind fan, the bell mouth and the drain pan cooperating in separating, in an airtight manner, a primary side and secondary side of the wind fan from each other; an electric component box attached to the bell mouth; and an electric heater disposed in the casing above the electric component box.

7. An air conditioner according to claim 5 or 6, wherein the electric heater is exposed between the drain pan and the wind fan when the electric component box and the bell mouth are detached from the casing, and hence can be detached from the casing, with the drain pan and the wind fan maintained as they are.

8. A ceiling attachment type air conditioner, substantially as hereinbefore described with reference to Figs. 1 to 3, Figs. 4 and 5, Figs. 6 to 8, Fig. 9A, Fig. 9B, Fig. 9C or Fig. 9D of the accompanying drawings.