AU2013100648A4 - Ceiling-embedded duct type indoor unit - Google Patents

Abstract

In a ceiling-embedded duct type indoor unit (1), a heat exchanger (4) is inclined toward a front surface side of a casing (2) moving from a lower end of the heat exchanger (4) toward an upper end of the heat exchanger (4). The casing (2) has an outer shape that projects upward in such a way that a section (2a) near the front surface where the heat exchanger (4) is disposed becomes larger than the height dimension of a section (2b) near a back surface where a fan (3) is disposed, and an inner surface (27) near an upper surface forming an air passage (23) has an inclined inner surface (27a) that is inclined in such a way as to follow the inclination of the heat exchanger (4) moving toward the front surface side of the casing (2). <Selected Drawing> Fig. 1 -- C,, C** -C 0c)O

Description

CEILING-EMBEDDED DUCT TYPE INDOOR UNIT TECHNICAL FIELD The present invention relates to a ceiling-embedded duct type indoor unit and particularly to a ceiling-embedded duct type indoor unit configured by disposing, in an air 5 passage formed in a casing and leading from a back surface side of the casing to a front surface side of the casing, a fan and a heat exchanger sequentially from the back surface side toward the front surface side. BACKGROUND ART Conventionally, there have been ceiling-embedded duct type indoor units such as the 10 one described in patent citation 1 (JP-A No. 2008-157503). This ceiling-embedded duct type indoor unit is configured by disposing, in an air passage formed in a casing and leading from a back surface side of the casing to a front surface side of the casing, a fan and a heat exchanger sequentially from the back surface side toward the front surface side. The ceiling-embedded duct type indoor unit is installed in a ceiling plenum of a building or the like, and a casing air 15 inlet and a casing air outlet that are in communication with the air passage are connected to an inlet duct and an outlet duct. In the ceiling-embedded duct type indoor unit described in patent citation 1, due to the restriction of the size of the ceiling plenum such as interference with ceiling beams, there are cases where installation cannot be performed when the height dimension of the casing 20 becomes larger. In particular, when the heat exchanger is enlarged to improve air conditioning performance because of the demand in recent years to save energy, there arise cases where the height dimension of the casing must be made significantly larger, and in these cases installation in the ceiling plenum becomes even more difficult. For this reason, in ceiling-embedded duct type indoor units, balancing the two 25 problems of ensuring air conditioning performance and installation in the ceiling plenum is desired. Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field 30 relevant to the present disclosure as it existed before the priority date of each claim of this application. Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other 1 element, integer or step, or group of elements, integers or steps. SUMMARY OF INVENTION It is a desired advantage of an embodiment of the present invention to enable installation in a ceiling plenum while ensuring air conditioning performance in a ceiling 5 embedded duct type indoor unit configured by disposing, in an air passage formed in a casing and leading from a back surface side of the casing to a front surface side of the casing, a fan and a heat exchanger sequentially from the back surface side toward the front surface side. A ceiling-embedded duct type indoor unit pertaining to an aspect is a ceiling-embedded duct type indoor unit configured by disposing, in an air passage formed in a casing and leading 10 from a back surface side of the casing to a front surface side of the casing, a fan and a heat exchanger sequentially from the back surface side toward the front surface side. Here, the heat exchanger is inclined toward the front surface side of the casing moving from a lower end of the heat exchanger toward an upper end of the heat exchanger. Additionally, the casing has an outer shape that projects upward in such a way that a section near the front surface where the 15 heat exchanger is disposed becomes larger than the height dimension of a section near the back surface where the fan is disposed, and an inner surface near an upper surface forming the air passage has an inclined inner surface that is inclined in such a way as to follow the inclination of the heat exchanger moving toward the front surface side of the casing. In an embodiment, the casing is configured to have an outer shape that projects upward 20 in such a way that the section near the front surface where the heat exchanger is disposed becomes larger than the height dimension of the section near the back surface where the fan is disposed. For this reason, the heat exchanger can be extended upward and the height dimension of the section near the back surface of the casing can be made smaller. This enables enlargement of the heat exchanger and installation in the ceiling plenum. 25 However, when the outer shape of the casing described above is employed, in regard to the air passage formed in the casing also, just the section where the heat exchanger is disposed comes to have an upwardly expanded shape. At this time, if the inner surface near the upper surface forming the air passage is configured to rise erectly upward abruptly from the section near the back surface of the casing toward the section near the front surface, it becomes 30 difficult for the air blown out from the fan to reach the upper portion of the heat exchanger. For this reason, there is the concern that the flow rate of the air traveling through the upper portion of the heat exchanger will drop, the heat exchange capacity of the heat exchanger will not be able to be exhibited despite the fact that the heat exchanger has been enlarged, and the desired air conditioning performance will not be obtained. 2 Thus, in the above-mentioned embodiment, the outer shape of the casing described above is employed and the inner surface near the upper surface forming the air passage is configured to have the inclined inner surface that is inclined in such a way as to follow the inclination of the heat exchanger moving toward the front surface side of the casing. For this 5 reason, it becomes easier for the air blown out from the fan to reach the upper portion of the heat exchanger. Because of this, a drop in the flow rate of the air traveling through the upper portion of the heat exchanger can be controlled, the heat exchange capacity of the heat exchanger can be exhibited, and the desired air conditioning performance can be obtained. In this way, here, by employing the outer shape of the casing described above and 10 configuring the inner surface near the upper surface forming the air passage to have the inclined inner surface that follows the inclination of the heat exchanger, installation in the ceiling plenum can be enabled while ensuring air conditioning performance. The inclined inner surface may be parallel to the inclination of the heat exchanger. In an embodiment, the air blown out from the fan generally evenly reaches all up-and 15 down direction positions of the upper portion of the heat exchanger. Because of this, the heat exchange capacity of the heat exchanger can be sufficiently exhibited. If the inclined inner surface is not parallel to the inclination of the heat exchanger but is configured to have a smaller angle of inclination than the inclination of the heat exchanger, the air flow resistance in the vicinity of the upper end of the upper portion of the heat exchanger becomes greater and 20 it becomes difficult for the air blown out from the fan to evenly reach the upper portion of the heat exchanger. A casing air outlet that blows out air that has traveled through the heat exchanger to the outside of the casing may be formed in the front surface of the casing. Additionally, the casing air outlet may be disposed in a position near the upper surface of the casing. 25 In an embodiment, it becomes easier for the air blown out from the fan to be guided toward the upper portion of the heat exchanger. Because of this, it can be made even easier for the air blown out from the fan to reach the upper portion of the heat exchanger. The height dimension of the section near the front surface may be 1.2 times to 1.6 times the height dimension of the section near the back surface, 30 The air passage may be partitioned by a partition panel into a fan compartment near the back surface where the fan is disposed and a heat exchanger compartment near the front side where the heat exchanger is disposed. Additionally, the boundary between the section near the front surface and the section near the back surface may be positioned on the heat exchanger compartment side of 3 the partition panel. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a side view (with a side surface of a casing removed) of a ceiling-embedded duct type indoor unit pertaining to an embodiment of the present invention. 5 FIG. 2 is a plan view (with an upper surface of the casing removed) of the ceiling embedded duct type indoor unit. FIG. 3 is a side view (with a side surface of a casing removed) of a ceiling-embedded duct type indoor unit pertaining to a comparative example (a case where the angle of inclination of an inclined inner surface has been made larger than the inclination of a heat 0 exchanger). FIG. 4 is a side view (with a side surface of a casing removed) of a ceiling-embedded duct type indoor unit pertaining to a comparative example (a case where the angle of inclination of an inclined inner surface has been made smaller than the inclination of a heat exchanger). 5 DESCRIPTION OF EMBODIMENT An embodiment of a ceiling-embedded duct type indoor unit pertaining to the present invention will be described below on the basis of the drawings. The specific configurations of the ceiling-embedded duct type indoor unit pertaining to the present invention are not limited to the embodiment described below and can be changed without departing from the 0 gist of the invention. (1) Configuration of Ceiling-embedded Duct Type Indoor Unit FIG. 1 is a side view (with a side surface of a casing 2 removed) of a ceiling embedded duct type indoor unit 1 pertaining to the embodiment of the present invention. FIG. 2 is a plan view (with an upper surface of the casing 2 removed) of the ceiling 25 embedded duct type indoor unit 1. The ceiling-embedded duct type indoor unit 1 is installed in a ceiling plenum of a building or the like and mainly has the casing 2, a fan 3, and a heat exchanger 4. Here, the ceiling-embedded duct type indoor unit 1 is configured by disposing, in an air passage 23 formed in the casing 2 and leading from a back surface side of the casing 2 to a front surface 30 side of the casing 2, the fan 3 and the heat exchanger 4 sequentially from the back surface side toward the front surface side. In the description below, "back surface of the casing" refers to the surface on the upstream side in the flow direction of the air (the surface on the right side of the page in FIG. 1 and FIG. 2) in a state in which the ceiling-embedded duct type indoor unit 1 has been installed in the ceiling plenum and "front surface of the casing" refers

A

to the surface on the downstream side in the flow direction of the air (the surface on the left side of the page in FIG 1 and FIG 2) in a state in which the ceiling-embedded duct type * indoor unit I has been installed in the ceiling plenum. <Basic Configuration> 5 The casing 2 is a box-shaped member that houses devices such as the fan 3 and the heat exchanger 4. A casing air inlet 21 that sucks air into the casing 2 through an inlet duct (indicated by a long dashed double-short dashed line in FIG 1 and FIG. 2) is formed in the back surface of the casing 2. Further, a casing air outlet 22 that blows out air that has traveled through the heat exchanger 4 to the outside of the casing 2 through an outlet duct 0 (indicated by a long dashed double-short dashed line in FIG 1 and FIG 2) is formed in the front surface of the casing 2. Additionally, the air passage 23 that leads from the back surface side to the front surface side is formed in the casing 2. Further, a partition panel 26 that partitions the air passage 23 into a fan compartment 24 that is near the back surface and in communication with the casing air inlet 21 and a heat exchanger compartment 25 that is near 5 the front surface and in communication with the casing air outlet 22 is disposed in the casing 2. The partition panel 26 is a panel-shaped member parallel to the front surface and the back surface of the casing 2. Two communication openings 26a and 26b are formed side by side laterally in the partition panel 26. Details concerning the outer shape of the casing 2 and the shape of the air passage 23 will be described later. 0 The fan 3 is disposed in the fan compartment 24 and is a device that sucks air through the casing air inlet 21 into the fan compartment 24, increases the pressure of the air, and blows out the air through the communication openings 26a and 26b in the partition panel 26 into the heat exchanger compartment 25. Here, the fan 3 comprises two double-suction type sirocco fans. The fan 3 mainly has two impellers 31a and 31b, two scroll casings 32a and 25 32b that house the impellers 31 a and 3 lb, and a motor 33 that drives the impellers 31 a and 31b. The impellers 3 Ia and 31b are multi-blade impellers disposed side by side toward the sides of the casing 2. The scroll casings 32a and 32b have two scroll air inlets 33a and 33b formed in both side surfaces and scroll air outlets 34a and 34b formed in the front surface sides. The scroll air outlets 34a and 34b are disposed in such a way as to correspond to the 30 communication openings 26a and 26b in the partition panel 26. Here, the motor 33 is disposed between the scroll casing 32a and the scroll casing 32b as seen in a plan view of the casing 2 and has a shaft coupled to the two impellers 31 a and 31 b. Although a configuration where the one motor 33 drives the two double-suction type sirocco fans is employed here as the fan 3, the fan 3 is not limited to this. The number of sirocco fans may also be a number r% other than two, the number of motors may also be different, and the fan may also be another type of fan. The heat exchanger 4 is disposed in the heat exchanger compartment 25 and is a device for exchanging heat with the air whose pressure has been increased by the fan 3 in the 5 fan compartment 24 and which has been blown out through the scroll air outlets 34a and 34b into the heat exchanger compartment 25. Here, a cross fin and tube heat exchanger is employed as the heat exchanger 4. Further, the heat exchanger 4 is inclined toward the front surface side of the casing 2 moving from a lower end of the heat exchanger 4 toward an upper end of the heat exchanger 4. Further, a drain pan 41 is disposed on the underside of the heat 0 exchanger 4. Although a cross fin and tube heat exchanger is employed here as the heat exchanger 4, the heat exchanger 4 is not limited to this. <Measures for Facilitating Enlargement of Heat Exchanger and Installation in Ceiling Plenum> In the ceiling-embedded duct type indoor unit I having the basic configuration 5 described above, due to the restriction of the size of the ceiling plenum such as interference with ceiling beams, there are cases where installation cannot be performed when the height dimension of the casing 2 becomes larger. In particular, when the heat exchanger 4 is enlarged to improve air conditioning performance because of the demand in recent years to save energy, there arise cases where the height dimension of the casing 2 must be made 0 significantly larger, and in these cases installation in the ceiling plenum becomes even more difficult. For this reason, in the ceiling-embedded duct type indoor unit 1, balancing the two problems of ensuring air conditioning performance and installation in the ceiling plenum is desired. 25 Thus, here, the following measures are implemented in regard to the outer shape of the casing 2 and the shape of the air passage 23. Here, first, as shown in FIG. 1, the casing 2 is configured to have an outer shape that projects upward in such a way that a section 2a (a height dimension h2) near the front surface where the heat exchanger 4 is disposed becomes larger than a height dimension hi of a 30 section 2b near the back surface where the fan 3 is disposed. Here, the height dimension h2 of the section 2a near the front surface is about 1.2 times to 1.6 times the height dimension hl of the section 2b near the back surface. Further, the boundary between the section 2a near the front surface and the section 2b near the back surface does not coincide with the boundary between the fan compartment 24 and the heat exchanger compartment 25 (that is, the position ra of the partition panel 26) but is positioned on the heat exchanger compartment 25 side of the partition panel 26. For this reason, the heat exchanger 4 can be extended upward and the height dimension hI of the section 2b near the back surface of the casing 2 can be made smaller. This enables enlargement of the heat exchanger 4 and installation in the ceiling 5 plenum. However, when the outer shape of the casing 2 described above is employed, in regard to the air passage 23 formed in the casing 2 also, just the section where the heat exchanger 4 is disposed comes to have an upwardly expanded shape. At this time, if, like in the comparative example shown in FIG. 3, an inner surface 27 near the upper surface forming 0 the air passage 23 is configured to rise erectly upward abruptly from the section 2b near the back surface of the casing 2 toward the section 2a near the front surface, it becomes difficult for the air blown out from the fan 3 to reach the upper portion of the heat exchanger 4. Specifically, if the inner surface 27 near the upper surface forming the air passage 23 is configured to rise erectly upward abruptly from the section 2b near the back surface of the 5 casing 2 toward the section 2a near the front surface, the air pools in a space (a space SI indicated by a long dashed double-short dashed line in FIG. 3) in the neighborhood of this erect section of the air passage 23, When such pooling of the air occurs, it becomes difficult for the air blown out from the fan 3 to spread to the upper portion of the heat exchanger 4 and it becomes easier for the air blown out from the fan 3 to advance directly toward the front 0 surface side (see arrow F 1 denoting the flow of air in FIG 3). For this reason, there is the concern that the flow rate of the air traveling through the upper portion of the heat exchanger 4 will drop, the heat exchange capacity of the heat exchanger 4 will not be able to be exhibited despite the fact that the heat exchanger 4 has been enlarged, and the desired air conditioning performance will not be obtained. 25 Thus, here, the outer shape of the casing 2 described above is employed and the inner surface 27 near the upper surface forming the air passage 23 is configured to have an inclined inner surface 27a that is inclined in such a way as to follow the inclination of the heat exchanger 4 moving toward the front surface side of the casing 2. For this reason, it becomes easier for the air blown out from the fan 3 to reach the upper portion of the heat exchanger 4 30 (that is, the section of the heat exchanger 4 that projects further upward than the section 2b near the back surface) (see arrow F2 denoting the flow of air in FIG. 1). Because of this, a drop in the flow rate of the air traveling through the upper portion of the heat exchanger 4 can be controlled, the heat exchange capacity of the heat exchanger 4 can be exhibited, and the desired air conditioning performance can be obtained. 17 In this way, here, by employing the outer shape of the casing 2 described above and configuring the inner surface 27 near the upper surface forming the air passage 23 to have the inclined inner surface 27a that follows the inclination of the heat exchanger 4, installation in the ceiling plenum can be enabled while ensuring air conditioning performance. 5 In particular, here, as shown in FIG 1, the inclined inner surface 27a is configured to be parallel to the inclination of the heat exchanger 4. For this reason, the air blown out from the fan 3 generally evenly reaches all up-and-down direction positions of the upper portion of the heat exchanger 4. Because of this, the heat exchange capacity of the heat exchanger 4 can be sufficiently exhibited. If, like in the comparative example shown in FIG. 4, the inclined 0 inner surface 27a is not parallel to the inclination of the heat exchanger 4 but is configured to have a smaller angle of inclination than the inclination of the heat exchanger 4, the air flow resistance in the vicinity of the upper end of the upper portion of the heat exchanger 4 (see space S2 indicated by a long dashed double-short dashed line in FIG. 4) becomes greater and it becomes difficult for the air blown out from the fan 3 to evenly reach the upper portion of 5 the heat exchanger 4 (see arrow F3 denoting the flow of air in FIG. 4). Moreover, here, as shown in FIG. 1, the casing air outlet 22 is disposed in a position near the upper surface of the casing 2. For this reason, here, it becomes easier for the air blown out from the fan 3 to be guided toward the upper portion of the heat exchanger 4. Because of this, it can be made even easier for the air blown out from the fan 3 to reach the 0 upper portion of the heat exchanger 4. INDUSTRIAL APPLICABILITY The present invention is widely applicable to ceiling-embedded duct type indoor units configured by disposing, in an air passage formed in a casing and leading from a back surface side of the casing to a front surface side of the casing, a fan and a heat exchanger sequentially 25 from the back surface side toward the front surface side. REFERENCE SIGNS LIST 1 Ceiling-embedded Duct Type Indoor Unit 2 Casing 2a Section near Front Surface 30 2b Section near Back Surface 3 Fan 4 Heat Exchanger 22 Casing Air Outlet 23 Air Passage 24 Fan Compartment 25 Heat Exchanger Compartment 26 Partition Panel 27 Inner Surface 5 27a Inclined Inner Surface 9

Claims (5)

1. A ceiling-embedded duct type indoor unit configured by disposing, in an air passage formed in a casing and leading from a back surface side of the casing to a front surface side of the casing, a fan and a heat exchanger sequentially from the back surface side toward the 5 front surface side, wherein the heat exchanger is inclined toward the front surface side of the casing moving from a lower end of the heat exchanger toward an upper end of the heat exchanger, and the casing has an outer shape that projects upward in such a way that a section near J the front surface where the heat exchanger is disposed becomes larger than the height dimension of a section near the back surface where the fan is disposed, and an inner surface near an upper surface forming the air passage has an inclined inner surface that is inclined in such a way as to follow the inclination of the heat exchanger moving toward the front surface side of the casing. 5

2. The ceiling-embedded duct type indoor unit according to claim 1, wherein the inclined inner surface is parallel to the inclination of the heat exchanger.

3. The ceiling-embedded duct type indoor unit according to claim 1 or 2, wherein a casing air outlet that blows out air that has traveled through the heat exchanger to the outside of the casing is formed in the front surface of the casing, and the casing air outlet is disposed 0 in a position near the upper surface of the casing.

4. The ceiling-embedded duct type indoor unit according to any one of claims I to 3, wherein the height dimension of the section near the front surface is 1.2 times to 1.6 times the height dimension of the section near the back surface.

5. The ceiling-embedded duct type indoor unit according to any one of claims 1 to 4, 25 wherein the air passage is partitioned by a partition panel into a fan compartment near the back surface where the fan is disposed and a heat exchanger compartment near the front side where the heat exchanger is disposed, and the boundary between the section near the front surface and the section near the back surface is positioned on the heat exchanger compartment side of the partition panel. 30 10