Indoor unit and air-conditioning apparatus

An indoor unit according to the present invention includes: an air-sending portion, which includes a casing having a rectangular air outlet and accommodating an impeller including a plurality of blades; a heat exchanger, which is configured to exchange heat with gas sent from the air-sending portion; and a guide portion, which includes an upper guide defining a passage for the gas and being arranged between an upper edge portion of the air outlet and an upper end portion of the heat exchanger and a lower guide defining a passage for the gas and being arranged between a lower edge portion of the air outlet and a lower end portion of the heat exchanger, and is open at side regions of the guide portion.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. national stage application of International Application No. PCT/JP2017/039127, filed on Oct. 30, 2017, and is based on International Application No. PCT/JP2016/082241, filed on Oct. 31, 2016, the contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to an indoor unit and an air-conditioning apparatus including the same. In particular, the present invention relates to a structure for rectifying gas inside the indoor unit.

BACKGROUND

There has been disclosed, for example, an indoor unit for an air-conditioning apparatus, which includes a diffuser portion enlarged in a height direction and a width direction from an air outlet of each of spiral casings to the vicinity of a heat exchanger (see, for example, Patent Literature 1).

PATENT LITERATURE

In the related-art ceiling-concealed indoor unit, a width of the heat exchanger is larger than widths of air outlets of an air-sending portion. Therefore, an air velocity distribution of air passing through the heat exchanger is non-uniform in the width direction. Therefore, a pressure loss in the heat exchanger is increased, with the result that, for example, degradation in efficiency of fans or increase in noise may occur. Further, in order to downsize the indoor unit, the heat exchanger is arranged obliquely relative to the air outlets of the spiral casings. Therefore, a distance between the air outlets of the spiral casings and the heat exchanger is increased. As a result, air streams discharged from the fans are influenced by a shape of a wall surface of an air passage in the unit, with the result that, for example, degradation in efficiency of the fans or increase in noise may occur.

For example, through application of the technology described in Patent Literature 1, a difference between the widths of the air outlets of the air-sending portion and the width of the heat exchanger, and a distance from discharge ports of the fans to the heat exchanger are reduced. However, air passages are sharply enlarged at enlarging portions of the diffusers. Therefore, air streams do not sufficiently spread along wall surfaces of the air passages, with the result that a pressure loss may adversely occur. Further, guides are provided to the diffusers so that air streams easily spread. However, there is a problem in that an improvement effect of the enlargement of the diffusers cannot be sufficiently obtained due to a pressure loss in the guides. Further, turbulence of an air stream occurs in a space between the adjacent spiral casings in air outlet passages of the spiral casings. Therefore, a vortex is liable to occur, with the result that a pressure loss may occur.

SUMMARY

The present invention has been made in view of the problems described above, and has an object to provide, for example, an indoor unit, which achieves further improvement in efficiency and reduction in noise.

According to one embodiment of the present invention, there is provided an indoor unit, including: an air-sending portion, which includes a casing having a rectangular air outlet and accommodating an impeller including a plurality of blades; a heat exchanger, which is configured to exchange heat with gas sent from the air-sending portion; and a guide portion, which includes an upper guide defining a passage for the gas and being arranged between an upper edge portion of the air outlet and an upper end portion of the heat exchanger, and a lower guide defining a passage for the gas and being provided between a lower edge portion of the air outlet and a lower end portion of the heat exchanger, and which is open at side regions of the guide portion.

Further, according to one embodiment of the present invention, an air-conditioning apparatus includes the indoor unit described above.

According to one embodiment of the present invention, gas sent from the air outlet of the air-sending portion to the heat exchanger is rectified so that the pressure loss can be reduced. Further, a vortex region generated in the vicinity of the air outlet of the air-sending portion can be reduced. Moreover, the side regions are open so that an air velocity distribution of gas flowing into the heat exchanger is uniform. Therefore, for example, further improvement in efficiency and reduction in noise can be attained.

DETAILED DESCRIPTION

Now, an indoor unit and other apparatus according to embodiments of the present invention are described referring to the drawings. In the drawings referred to below, components denoted by the same reference symbols correspond to the same or equivalent components. This is common throughout the embodiments described below. Further, the forms of the components described herein are merely examples, and the components are not limited to the forms described herein. In particular, the combinations of the components are not limited to only the combinations in each embodiment, and the components described in another embodiment may be applied to still another embodiment. Further, in the following description, the upper part and the lower part of the drawings are referred to as “upper side” and “lower side”, respectively. Further, for ease of understanding, terms indicating directions (for example, “right”, “left”, “front”, and “rear”) are used as appropriate. Those terms are used for description, but do not limit the invention of the present application. Further, in the drawings, the size relationship among components sometimes differs from actual relationships.

FIG. 1is a perspective schematic view of an indoor unit according to Embodiment1of the present invention. Further,FIG. 2is an explanatory schematic view of an internal structure of the indoor unit according to Embodiment 1 of the present invention. The indoor unit according to Embodiment 1 is a device installed, for example, above a ceiling to, for example, heat, cool, humidify, or dehumidify a target space as an air-conditioning apparatus, a humidifier, a dehumidifier, a freezing machine, or other devices. The indoor unit according to Embodiment 1 is herein described as an indoor unit for an air-conditioning apparatus. Therefore, description is made assuming that gas is air.

As illustrated inFIG. 1andFIG. 2, the indoor unit according to Embodiment 1 includes a case1. As the shape of the case1, any suitable shape may be employed. In this case, the case1has a rectangular cuboid shape as an example. The case1includes an upper surface portion1a, a lower surface portion1b, and a side surface portion1c. The side surface portion1cincludes four surfaces. Further, the indoor unit is partitioned into a main body unit15and an air-sending unit16by a partition plate10described later as a boundary. The main body unit15and the air-sending unit16are combined with each other to form the indoor unit.

A case air-outlet2is formed on one surface side among the surfaces of the side surface portion1cof the case1. As the shape of the case air-outlet2, any suitable shape may be employed. In this case, the case air-outlet2has a rectangular shape. Further, a case air-inlet8is formed in a surface on a side opposite to the surface having the case air-outlet2among the surfaces of the side surface portion1cof the case1. As the shape of the case air-inlet8, any suitable shape may be employed. In this case, the case air-inlet8has a rectangular shape. Although not particularly limited, for example, a filter for removing dust from gas may be provided to the case air-inlet8. In the indoor unit, the surface having the case air-outlet2is referred to as a front (front surface). Upward and downward directions as viewed from the front side are referred to as a height direction or an upper-and-lower direction. Further, right and left directions are referred to as a width direction or a rotation shaft direction, and front and rear directions are referred to as a front-and-rear direction or a depth direction.

In the case1, there are accommodated an air-sending portion20, a fan motor4, and a heat exchanger6. The heat exchanger6is arranged at a position in a passage of air from an air outflow side of the air-sending portion20to the case air-outlet2. The heat exchanger6is configured to adjust at least one of a temperature or a humidity of air sent from the air-sending portion20. In this case, the heat exchanger6has a rectangular shape in conformity with the shape of the case air-outlet2. A configuration and a mode of the heat exchanger6are not particularly limited. The heat exchanger6in Embodiment 1 is not a special type, and a publicly-known type is used. For example, a fin-and-tube heat exchanger exchanges heat between air passing through the heat exchanger6and refrigerant passing through heat transfer pipes (not shown), to thereby adjust at least one of a temperature or a humidity of air.

The fan motor4and the air-sending portion20form an air-sending device. The fan motor4is driven through supply of electric power to rotate fans3inside spiral casings7. The fan motor4is supported by, for example, a motor support4afixed to the upper surface portion1aof the case1. The fan motor4includes a rotation shaft X. The rotation shaft X is arranged to extend in parallel to the width direction along the surface having the case air-inlet8and the surface having the case air-outlet2among the surfaces of the side surface portion1c.

The air-sending portion20in Embodiment 1 includes one or a plurality of spiral casings7. As illustrated inFIG. 2, the indoor unit according to Embodiment 1 includes two spiral casings7. Further, in each of the spiral casings7, the multiblade and centrifugal fan3and a bellmouth5are installed. The fans3of the air-sending portion20are mounted to the rotation shaft X of the fan motor4described above. In the indoor unit illustrated inFIG. 2, the two fans3of the spiral casings7are mounted to the rotation shaft X in parallel with each other. Therefore, the two fans3and the two spiral casings7are arrayed in the width direction. In this case, description is made assuming that the air-sending portion20includes the two spiral casings7and the two fans3. However, the number of the spiral casings7and the fans3to be installed is not limited.

FIG. 3andFIG. 4are each an explanatory view of the indoor unit for an air-conditioning apparatus according to Embodiment 1 of the present invention.FIG. 3is an illustration of the internal structure of the indoor unit as viewed from top of the main body unit. Further,FIG. 4is an illustration of the internal structure of the indoor unit when the indoor unit is viewed in the rotation shaft direction. Moreover,FIG. 5is a perspective view of the air-sending portion20of the indoor unit for an air-conditioning apparatus according to Embodiment 1 of the present invention.

The fans3of the air-sending portion20each serve as an impeller configured to generate flow of air that is sucked into the case1through the case air-inlet8and blown out into a target space through the case air-outlet2. The fans3each include a main plate3a, a side plate3c, and a plurality of blades3d. The main plate3ahas a disc shape, and includes a boss portion3bat a center portion thereof. The rotation shaft X of the fan motor4is connected to the center of the boss portion3b. The fans3are rotated through drive of the fan motor4. A rotation direction of the fans3corresponds to the height direction (upper-and-lower direction). The side plate3cis provided to be opposed to the main plate3a, and has a ring shape. A hole of the ring of the side plate3cserves an inflow port into which air flows through the bellmouth5. The plurality of blades3dare provided between the main plate3aand the side plate3cto surround the rotation shaft X. The plurality of blades3dhave the same shape. The blades3dare each formed of a forward curved vane in which a blade trailing edge on an outer peripheral side is located forward in the rotation direction relative to a blade leading edge on an inner peripheral side.

The spiral casings (scroll casings)7are each configured to receive the fan3to surround the fan3. The spiral casing7is configured to rectify air having been blown out from the fan3. The spiral casing7includes a peripheral wall7aextending along an outer peripheral end of the fan3. The peripheral wall7aincludes a tongue portion7bat one portion. An end portion of a portion protruding from the peripheral wall7arelative to a portion corresponding to the tongue portion7bserves as a fan air-outlet7d. Through rotation of the fan3, air flows through the fan3to be sent from the fan air-outlet7d. The fan air-outlet7dhas a rectangular shape. The fan air-outlet7dthat serves as an air outlet of the air-sending portion20is opened toward the heat exchanger6and the case air-outlet2. Therefore, air having been blown out from the air-sending portion20generally flows in a direction toward the heat exchanger6and the case air-outlet2.

Further, at least one fan air-inlet9is formed in a side wall7cof the spiral casing7. The bellmouth5is arranged along the fan air-inlet9. The bellmouth5is configured to rectify air flowing into the fan3. The bellmouth5is positioned to face the inflow port for air of the fan3. The partition plate10is a plate for partitioning a space between the fan air-inlets9and the fan air-outlets7d. The fan air-inlets9of the spiral casings7are located in a space on the air-sending unit16side, and the fan air-outlets7dof the spiral casings7are located in a space on the main body unit15side.

The indoor unit according to Embodiment 1 includes guide portions11. The guide portions11each serve as a wall for guiding air sent from the fan air-outlet7dof the spiral casing7to the heat exchanger6. In this case, guides are provided at upper and lower edges of the fan air-outlet7dthat intersect the height direction being the rotation direction of the fan3. In Embodiment 1, an upper guide11aand a lower guide11bare provided. The upper guide11aand the lower guide11bare formed not merely by extending the upper edge and the lower edge of the fan air-outlet7dalong an orientation of the fan air-outlet7d, but are installed to enlarge the fan air-outlet7afrom the upper edge portion and the lower edge portion of the fan air-outlet7dof the spiral casing7toward an upper end portion and a lower end portion of the heat exchanger6.FIG. 5is an illustration of a relationship between the fan air-outlet7dand an end surface of the guide portion11when the air-sending portion20is viewed from the fan air-outlet7dside. With this, air sent from the fan air-outlet7dcan be rectified while increasing air volume. Further, edges do not extend along the height direction, the height direction being substantially equal to the rotation direction of the fan3viewed in the direction of front-back direction of the fan. That is, there are no extensive guides along the upper and lower guides11aand11bin so that the lateral side is open.

For example, although it is advantageous to close the side regions when air is to be guided in a set direction, air flowing along the wall is to be blown out while being sharply spread in the width direction after passing along the wall. Therefore, the air flowing into the heat exchanger6differs in air velocity in the width direction so that an airflow velocity distribution is not uniform. In contrast, in the indoor unit according to Embodiment 1, walls on the side regions of the guide portion11are not extended, and the side regions are opened. Therefore, air having been blown out from the fan air-outlet7dof the spiral casing7spreads evenly in the width direction without stagnation. Thus, the air velocity distribution of air, which flows into the heat exchanger6, in the width direction is expected to become uniform. A material of the upper guide11aand the lower guide11bthat form the guide portion11is not limited. For example, a material such as polystyrene foam may be employed. Further, the guide portion11may have any shape in an extension direction when the guide portion11extends toward the upper end portion and the lower end portion of the heat exchanger6.

Next, description is made of flow of air when the fans3of the air-sending portion20are rotated. When electric power is supplied, the fan motor4is driven so that the fans3are rotated. When the fans3are rotated, for example, air in a room to be air-conditioned flows into the case1through the case air-inlet8. Air having been sucked into the case1passes through the fan air-inlets9of the spiral casings7, and is guided by the bellmouths5to flow into the fans3. Further, the air having flowed into the fans3is blown out in a radial direction and an outward direction of the fans3. The air having been blown out from the fans3passes through the spiral casings7, and then, is blown out through the fan air-outlets7dof the spiral casings7. The air having been blown out passes through the heat exchanger6. The air supplied to the heat exchanger6exchanges heat when passing through the heat exchanger6to be adjusted in humidity. After that, the air is blown out to the outside of the case1through the case air-outlet2.

In the indoor unit according to Embodiment 1, the air having been blown out from each of the fan air-outlets7dof the spiral casings7flows along the guide portion11. The guide portion11extending to the heat exchanger6is provided. Thus, the air having been blown out flows in the depth direction to reach the heat exchanger6without being influenced by the shape of the case1and being separated from the upper guide11aand the lower guide11b. Further, the air having been blown out through the fan air-outlet7devenly spreads in the width direction. Therefore, the air velocity can be uniform. As described above, the influence of the shape of the case1can be suppressed. Further, an air vortex can be prevented from being generated, for example, in the vicinities of the partition plate10and the fan air-outlets7d.

With the spiral casings7in Embodiment 1 each having the configuration described above, the passing air velocity in the heat exchanger6is uniformized to suppress a vortex region in the vicinity of the fan air-outlet7d. Thus, a pressure loss caused by turbulence of an air stream can be reduced so that improvement in efficiency and reduction in noise can be attained due to improvement in air volume and static pressure effect.

FIG. 6is an explanatory view of an indoor unit for an air-conditioning apparatus according to Embodiment 2 of the present invention.FIG. 6is an illustration of an internal structure of the indoor unit as viewed from the upper surface side. Next, with reference toFIG. 6, description is made of the indoor unit according to Embodiment 2 of the present invention.

In the indoor unit according to Embodiment 1 described above, the upper guide11aand the lower guide11bare provided at the upper and lower portions of the air outlet of each of the spiral casings7so that the air having been blown out from each of the spiral casings7is guided to the upper and lower end portions of the heat exchanger6. In the indoor unit according to Embodiment 2, a wall surface of an air passage in the guide portion11extended from each of the spiral casings7has protrusions and depressions. In this case, the guide portion11has ribs12. The ribs12inFIG. 6each have a rectangular parallelepiped shape. The ribs12in Embodiment 2 are formed to extend along the depth direction in which air flows through rotation of the fan3. Therefore, air flowing from the spiral casing7to the heat exchanger6can further be rectified along the wall surface of the guide portion11. In this case, the ribs12are formed, but, for example, grooves may be formed.

FIG. 7andFIG. 8are each a view for illustrating the shapes of the ribs12of the guide portion11in Embodiment 2 of the present invention. InFIG. 6referred to above, the ribs12each having a rectangular cuboid shape are illustrated. However, the shape of each of the ribs12is not limited thereto. For example, as illustrated inFIG. 7, the ribs12may each have a streamline shape. Further, as illustrated inFIG. 8, the ribs12may each have an arc shape.

As described above, in the indoor unit according to Embodiment 2, the guide portion11has the ribs12. Thus, flow of air in the guide portion11can be rectified. Therefore, in addition to the effects described in Embodiment 1, separation of an air stream can be prevented in the air passage on the air outlet side in the spiral casing7. Therefore, a pressure loss can be reduced so that improvement in efficiency and reduction in noise can be attained due to improvement in air volume and static pressure effect.

FIG. 9is an explanatory view of an indoor unit for an air-conditioning apparatus according to Embodiment 3 of the present invention.FIG. 9is an illustration of an internal structure of the indoor unit as viewed from the upper surface side. Next, with reference toFIG. 9, description is made of the indoor unit according to Embodiment 3 of the present invention.

In the indoor unit according to Embodiment 1 described above, the guide portion11is provided at the upper and lower portions of the air outlet of each of the spiral casings7so that the air having been blown out from each of the spiral casings7is guided to the upper and lower end portions of the heat exchanger6. The wall of the guide portion11in the indoor unit according to Embodiment 1 is parallel to the depth direction from the fan air-outlet7dside to the heat exchanger6side.

In the indoor unit according to Embodiment 3, the wall of the guide portion11has a shape enlarged in the width (lateral) direction being a direction toward the side wall7cfrom the air outlet side toward the heat exchanger6side. Therefore, air flowing out from the spiral casing7can be sufficiently spread. Further, the air velocity distribution of air, which passes through the heat exchanger6, in the width direction can further be uniform.

The outer peripheral portion enlarged in the side wall direction may be gradually enlarged in, for example, an arc shape. Further, an angle formed when the outer peripheral portion is enlarged is not limited, and, for example, the outer peripheral portion may be sharply enlarged.

As described above, in the indoor unit according to Embodiment 3, the wall of the guide portion11has a shape enlarged in the direction toward the side wall7cfrom the air outlet side toward the heat exchanger6side. Thus, the air velocity distribution of air, which passes through the heat exchanger6, in the width direction can be uniform. Therefore, in addition to the effects described in Embodiment 1, a vortex region can further be suppressed in the air passage on the air outlet side in the spiral casing7. Therefore, improvement in efficiency and reduction in noise can be attained due to improvement in air volume and static pressure effect.

FIG. 10is an explanatory view of the air-sending portion20of an indoor unit for an air-conditioning apparatus according to Embodiment 4 of the present invention. Next, with reference toFIG. 10, description is made of the indoor unit according to Embodiment 4 of the present invention.

The upper guide11aand the lower guide11bof the guide portion11in the indoor unit according to Embodiment 4 each include lateral inclined portions11cbeing inclined portions, which are formed by bending end portions in the lateral direction thereof. The lateral inclined portions11care formed by, for example, bending the end portions in the lateral direction of the upper guide11aand the lower guide11b.FIG. 10is an illustration of a relationship between the fan air-outlet7dand the end surface of the guide portion11when the air-sending portion20is viewed from the fan air-outlet7dside.

Also in the guide portion11in Embodiment 4, the side regions are not closed by the lateral inclined portions11cbut are opened. Further, the lateral inclined portions11care not perpendicular to the height direction, but each have an inclination. When the end portions in the lateral direction are formed to erect vertically, flow of air that spreads in the width direction is blocked, with the result that, for example, air velocity of air flowing into the heat exchanger6may not be uniform. It is preferred that an inclination angle α be 50 degrees or less.

Further, the upper guide11aand the lower guide11bmay be equal to each other or different from each other in, for example, inclination angle a and length of each of the lateral inclined portions11c. Further, the shape of each of the lateral inclined portions11cis not particularly limited. Further, any one of the upper guide11aand the lower guide11bmay have the lateral inclined portions11c.

As described above, in the air-conditioning apparatus according to Embodiment 4, the upper guide11aand the lower guide11beach include the lateral inclined portions11c. Thus, separation of an air stream in the direction toward the side wall7ccan be reduced. Therefore, in addition to the effects described in Embodiment 1 to Embodiment 3, a pressure loss can further be reduced so that improvement in efficiency and reduction in noise can be attained due to improvement in air volume and static pressure effect.

FIG. 11is an explanatory view of an indoor unit for an air-conditioning apparatus according to Embodiment 5 of the present invention.FIG. 11is an illustration of an internal structure of the indoor unit as viewed from the width direction side. Next, with reference toFIG. 11, description is made of the air-conditioning apparatus according to Embodiment 5 of the present invention.

For example, in the air-conditioning apparatus according to Embodiment 1, as illustrated inFIG. 5, the guide portion11is mounted to the spiral casing7to be integrated. However, the present invention is not limited thereto. In particular, in a case in which at least one of the upper guide11aor the lower guide11bof the guide portion11has a shape enlarged in the direction toward the side wall7cfrom the air outlet side toward the heat exchanger6side as in Embodiment 3, when the indoor unit is to be manufactured, the guide portion11cannot be caused to pass through the partition plate10. Therefore, after the tongue portion7bof the spiral casing7is caused to pass through the partition plate10, the portion being the guide portion11is to be mounted. Further, it is difficult to integrally form the air-sending portion20.

In view of this, in the air-conditioning apparatus according to Embodiment 5, the guide portions11are mounted to an inner wall of the case1on the main body unit15side so that the guide portions11are accommodated on the main body unit15side. Further, when the main body unit15and the air-sending unit16are to be combined with each other, the tongue portions7band the guide portions11are joined to each other. The guide portions11may be formed integrally with the partition plate10or other portions.

As described above, in the air-conditioning apparatus according to Embodiment 5, the guide portions11are formed on the main body unit15side so that assembly of the indoor unit that achieves the effects in Embodiment 1 to Embodiment 4 can easily be carried out.

FIG. 12is an explanatory view of an indoor unit for an air-conditioning apparatus according to Embodiment 6 of the present invention.FIG. 12is an illustration of an internal structure of the indoor unit as viewed from the upper surface side. In Embodiment 1 to Embodiment 5 described above, the upper guide11aand the lower guide11bof the guide portion11are mounted to each of the spiral casings7. However, the present invention is not limited thereto. For example, the common upper guide11aand the common lower guide11bmay be mounted to the plurality of spiral casings7.

Further, in Embodiment 1 to Embodiment 5 described above, description is made assuming that the heat exchanger6is a fin-and-tube heat exchanger. However, the present invention is not limited thereto. For example, in order to humidify air, a humidification member configured to allow water to drip is provided as a heat exchanger.

FIG. 13is an explanatory view of an indoor unit for an air-conditioning apparatus according to Embodiment 7 of the present invention.FIG. 13is an illustration of an internal structure of the indoor unit when the indoor unit is viewed in the rotation shaft direction. In the indoor unit according to Embodiment 1, as illustrated inFIG. 4, in the guide portion11defining the passage of air from the fan air-outlet7dto the heat exchanger6, the upper guide11abeing a wall having a leading surface for leading air on the upper side has a linear shape in the extension direction extending toward the heat exchanger6side.

The indoor unit according to Embodiment 7 includes upper guides11din place of the upper guides11a. As illustrated inFIG. 13, the upper guide11dhas a shape, which protrudes downward from the fan air-outlet7dtoward the heat exchanger6, in the extension direction. Therefore, the leading surface being the wall of the upper guide11dis a curved surface that warps from the lower side to the upper side in the course of extending from the fan air-outlet7dtoward the heat exchanger6.

As in the indoor unit according to Embodiment 7, the upper guide11dhas a shape, which protrudes downward in the course of extending from the fan air-outlet7dtoward the heat exchanger6, in the extension direction. Thus, the wall surface extends continuously with the fan air-outlet7dand the upper guide11d. Therefore, an abrupt spread loss of air blown out from the fan air-outlet7dcan be reduced.

Further, in the indoor unit according to Embodiment 7, the upper guide11dhas a shape, which protrudes downward, in the extension direction. Thus, air sent from the fan air-outlet7dcan be guided upward. As illustrated inFIG. 13, when the spiral casing7is installed under a state of being turned in a fan rotation direction (in a counterclockwise direction inFIG. 13), an orientation of the fan air-outlet7dat the upper edge portion corresponds to an orientation extending downward relative to the horizontal direction. In the indoor unit according to Embodiment 7, even when the upper edge portion of the fan air-outlet7dis oriented downward relative to the horizontal direction, the upper guide11dguides air upward along the wall surface so that the air can be sent to the upper end portion of the heat exchanger6. Therefore, unevenness of the air velocity distribution of air flowing into the heat exchanger6can be maintained to be smaller than in a case in which the leading surface is not provided at the upper portion.

FIG. 14is an explanatory view of an indoor unit for an air-conditioning apparatus according to Embodiment 8 of the present invention.FIG. 14is an illustration of an internal structure of the indoor unit when the indoor unit is viewed in the rotation shaft direction. In the indoor unit according to Embodiment 1, as illustrated inFIG. 4, in the guide portion11defining the passage of air from the fan air-outlet7dto the heat exchanger6, the lower guide11bbeing a wall having a leading surface for leading air on the lower side has a linear shape in the extension direction extending toward the heat exchanger6side.

The indoor unit according to Embodiment 8 includes lower guides11ein place of the lower guides11b. As illustrated inFIG. 14, the lower guide11ehas a shape, which protrudes downward from the fan air-outlet7dtoward the heat exchanger6, in the extension direction. Therefore, the leading surface being the wall of the lower guide11eis a curved surface that warps from the lower side to the upper side in the course of extending from the fan air-outlet7dtoward the heat exchanger6.

As in the indoor unit according to Embodiment 8, the lower guide11ehas a shape, which protrudes downward in the course of extending from the fan air-outlet7dtoward the heat exchanger6, in the extension direction. Thus, the wall surface extends continuously with the fan air-outlet7dand the lower guide11e. Therefore, an abrupt spread loss of air blown out from the fan air-outlet7dcan be reduced.

Further, in the indoor unit according to Embodiment 8, the lower guide11ehas a shape, which protrudes downward, in the extension direction. Thus, air sent from the fan air-outlet7dcan be guided upward. As illustrated inFIG. 14, when the spiral casing7is installed under a state of being turned in the fan rotation direction (in the counterclockwise direction inFIG. 14), an orientation of the fan air-outlet7dat the lower edge portion corresponds to an orientation extending downward with respect to a direction toward the heat exchanger6side. In the indoor unit according to Embodiment 8, even when the lower edge portion of the fan air-outlet7dis oriented downward with respect to the direction toward the heat exchanger6side, the lower guide11eguides air upward along the wall surface so that the air can be sent to the lower end portion of the heat exchanger6. Therefore, unevenness of the air velocity distribution of air flowing into the heat exchanger6can be maintained to be smaller than in a case in which the leading surface is not provided at the lower portion.

FIG. 15is an explanatory view of the air-sending portion20of an indoor unit for an air-conditioning apparatus according to Embodiment 9 of the present invention.FIG. 15is an illustration of a relationship between the fan air-outlet7dand the end surface of the guide portion11when the air-sending portion20is viewed from the fan air-outlet7dside. Next, with reference toFIG. 15, description is made of the indoor unit according to Embodiment 9 of the present invention.

In the guide portion11of the indoor unit according to Embodiment 9, when the air-sending portion20is viewed from the fan air-outlet7dside, the upper guide11aand the lower guide11beach have an arc shape. Therefore, a curved surface is formed on each of the upper guide11aand the lower guide11b. The upper guide11aand the lower guide11beach have an arc shape so that the lateral portions of each of the upper guide11aand the lower guide11bare inclined in the upper-and-lower direction. The side regions are not completely covered by the inclined portions of each of the upper guide11aand the lower guide11bbut are opened.

The upper guide11aand the lower guide11bmay be equal to each other or different from each other in, for example, curvature and bending degree of the curved surfaces of the upper guide11aand the lower guide11b. Further, the shape of each of the curved surfaces is not particularly limited. Further, any one of the upper guide11aand the lower guide11bmay have an arc shape.

As described above, in the air-conditioning apparatus according to Embodiment 9, there are provided the upper guide11aand the lower guide11beach having an arc shape inclined at the side regions. Thus, separation of an air stream on the side regions can be reduced. A pressure loss caused by turbulence of an air stream can be reduced so that improvement in efficiency and reduction in noise can be achieved due to improvement in air volume and static pressure effect. Further, a pressure loss can further be reduced so that improvement in efficiency and reduction in noise can be achieved due to improvement in air volume and static pressure effect.

FIG. 16is a view for illustrating a configuration of an air-conditioning apparatus according to Embodiment 10 of the present invention. In Embodiment 10, description is made of the air-conditioning apparatus including the indoor unit described in Embodiment 1 to Embodiment 9 described above. The air-conditioning apparatus inFIG. 16includes an outdoor unit100and an indoor unit200. The outdoor unit100and the indoor unit200are coupled to each other by refrigerant pipes to form a refrigerant circuit through which refrigerant flows. Among the refrigerant pipes, a pipe through which gas refrigerant flows is referred to as a gas pipe300, and a pipe through liquid refrigerant (sometimes, two-phase gas-liquid refrigerant) flows is referred to as a liquid pipe400.

The indoor unit200includes a load-side heat exchanger201and a load-side air-sending device202. Similarly to the heat exchanger6in Embodiment 1 to Embodiment 9, the load-side heat exchanger201is configured to exchange heat between refrigerant and air. For example, the load-side heat exchanger201functions as a condenser during a heating operation. The load-side heat exchanger201is configured to exchange heat between refrigerant flowing in from the gas pipe300and air so that the refrigerant is condensed and liquified (or brought into a two-phase gas-liquid state), and to allow the refrigerant to flow out to the liquid pipe400side. Meanwhile, the load-side heat exchanger201functions as an evaporator during a cooling operation. The load-side heat exchanger201is configured to exchange heat between refrigerant brought into a low-pressure state by, for example, an expansion device105and air so that the refrigerant receives heat of the air to be evaporated and gasified, and to allow the refrigerant to flow out to the gas pipe300side.

Further, the indoor unit200includes the load-side air-sending device202configured to adjust flow of air in order to efficiently perform heat exchange between refrigerant and air. The load-side air-sending device202is a device having the same function as that of the air-sending portion20including, for example, the fans3in Embodiment 1 to Embodiment 9. The load-side air-sending device202is driven to rotate at a velocity determined, for example, through setting of air volume by a user.

Meanwhile, in Embodiment 10, the outdoor unit100includes a compressor101, a four-way valve102, an outdoor-side heat exchanger103, an outdoor-side air-sending device104, and the expansion device (expansion valve)105.

The compressor101is configured to compress and discharge sucked refrigerant. The compressor101includes, for example, an inverter device so that a capacity of the compressor101(amount of refrigerant sent per unit time) can be finely changed by suitably changing an operating frequency. The four-way valve102is configured to switch flow of refrigerant during the cooling operation and flow of refrigerant during the heating operation based on an instruction from a controller (not shown).

Further, the outdoor-side heat exchanger103is configured to exchange heat between refrigerant and air (outdoor air). For example, the outdoor-side heat exchanger103functions as an evaporator during the heating operation. The outdoor-side heat exchanger103is configured to exchange heat between low-pressure refrigerant flowing in from the liquid pipe400and air so that the refrigerant is evaporated and gasified. Further, the outdoor-side heat exchanger103functions as a condenser during the cooling operation. The outdoor-side heat exchanger103is configured to exchange heat between refrigerant having been compressed in the compressor101and flowed in from the four-way valve102side and air so that the refrigerant is condensed and liquified. The outdoor-side heat exchanger103includes the outdoor-side air-sending device104. Also in the outdoor-side air-sending device104, a rotation speed of a fan may be finely changed by suitably changing an operating frequency of the fan motor4by an inverter device. Further, the air-sending portion20in Embodiment 1 to Embodiment 9 may be used as the outdoor-side air-sending device104. The expansion device105is provided to adjust, for example, a pressure of refrigerant by changing an opening degree.

As described above, the air-conditioning apparatus according to Embodiment 10 includes the indoor unit described in Embodiment 1 to Embodiment 9. Thus, improvement in efficiency and reduction in noise can be attained due to improvement in air volume and static pressure effect.

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.

INDUSTRIAL APPLICABILITY

In Embodiment 1 to Embodiment 10 described above, application to the air-conditioning apparatus is described. However, the present invention is not limited to those apparatus, and may be applied to, for example, other refrigeration cycle apparatus such as a freezing machine or a water heater, which form a refrigerant circuit, and are configured to perform cooling, dehumidification, or humidification.