Patent Description:
In general, an air conditioner refers to an apparatus that adjusts temperature, humidity, air flow, air distribution, and the like to provide an environment suitable for human activity by using a refrigeration cycle. The refrigeration cycle may include a compressor, a condenser, an evaporator, and a blower fan as main components. Air conditioners may be classified into split type air conditioners in which an indoor unit and an outdoor unit are separately installed and integrated type air conditioners in which both an indoor unit and an outdoors unit are installed in a cabinet. Among them, an indoor unit of a split type air conditioner includes a heat exchanger that exchanges heat with air introduced into a panel and a blower fan that draws air from an indoor room into the panel and returns the drawn air to the indoor room.

Indoor units of conventional air conditioners have been designed to minimize heat exchangers and maximize velocities and amounts of winds by increasing RPM of a blower fan. Thus, temperature of discharged air decreases and air is discharged to an indoor space after passing through a narrow and long air flow path. When discharged air is brought into direct contact with a user, the user may have cold and uncomfortable feelings. On the contrary, when discharged air is not brought into contact with the user, the user may have hot and uncomfortable feels.

In addition, an increase in the RPM of the blower fan to obtain a high velocity of wind, noise may be increased. In the case of a radiation air conditioner that does not use a blower fan, a larger panel is required to provide the same air conditioning capability as those using the blow fan. In addition, cooling rates are very low and manufacturing costs are very high.

<CIT>and <CIT> disclose an air conditioner having a blade. They do not however that the first blade comprises a plate having a size corresponding to that of the outlet.

Therefore, it is an aspect of the present invention to provide an air conditioner having various air discharging methods.

It is another aspect of the present invention to provide an air conditioner having improved capability of controlling air discharged through an air discharge port.

It is another aspect of the present invention to provide an air conditioner to prevent deterioration of cooling or heating performance caused by re-introduction of cooling or heating air into a heat exchanger.

In accordance with the invention an air conditioner according to claim <NUM> is provided.

The second blade may be integrated with the first blade and moves together with the first blade to the guide position or the closing position.

The air conditioner may further include a connecting blade to connect the first blade with the second blade. The connecting blade may form an inflow port through which air flows in and an outflow port through which air is discharged together with the first blade and the second blade.

The outflow port may be provided smaller than the inflow port to have a velocity of air discharged out of the outflow port greater than a velocity of air introduced into the inflow port.

The second blade may include a plurality of second blades arranged along a lengthwise direction of the first blade.

A rotary shaft of the blade may be located at the connecting blade.

The second blade may reduce an amount of air passing through the blade holes of the first blade among air flows blown from the blower fan when the blade is located in the guide position.

The second blade may be inclined with respect to the first blade.

The rotary shaft of the blade may be located closer to a front end of the outlet than a rear end of the outlet.

In accordance with one aspect of present disclosure, an air conditioner includes a housing mounted on or recessed in a ceiling and having an inlet port and an air discharge port, a heat exchanger located inside the housing, a blower fan configured to draw air into the housing through the inlet port and discharge air out of the housing through the air discharge port, a first blade configured to open or close the air discharge port, having a plurality of blade holes, and provided to discharge air through the plurality of blade holes, and a second blade spaced apart from the first blade.

The air conditioner may further include a first opening formed between one side of the first blade closer to the inlet port and the housing when the first blade opens the air discharge port, and a second opening formed between the other side of the first blade opposite to the one side and the housing when the first blade opens the air discharge port.

The second blade may increase an amount of air discharged through the first opening and the second opening by guiding air inside the housing toward the first opening and the second opening.

The housing may include a guide portion to guide air discharged through the first opening in a direction away from the inlet port.

The second blade forms a flow guide to guide air toward the blade holes when the first blade closes the air discharge port.

When the first blade opens the air discharge port, the second blade guides air toward the guide portion and the guide portion may guide air discharged through the first opening to push air discharged through the blade holes in a direction away from the inlet port.

When the first blade opens the air discharge port, a velocity of air discharged through the first opening may be greater than a velocity of air discharged through the blade holes.

The second blade may be located closer to one side of the first blade to increase an amount of air discharged through the first opening.

The second blade may be integrated with the first blade to rotate together therewith.

The air conditioner according to an embodiment may blow heat-exchanged air in different manners according to an environment of use.

The air conditioner according to an embodiment may discharge heat-exchanged air at different velocities. The air conditioner according to an embodiment may prevent deterioration of cooling or heating performance caused by re-introduction of heat-exchanged air into the heat exchanger.

For a more complete understanding of the present invention and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:.

<FIG>, discussed below, and the various embodiments used to describe the principles of the present invention in this document are by way of illustration only and should not be construed in any way to limit the scope of the invention.

Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.

It will be understood that, although the terms "first", "second", etc., may be used herein to describe various elements, these elements should not be limited by these terms. The above terms are used only to distinguish one component from another. For example, a first component discussed below could be termed a second component, and similarly, the second component may be termed the first component without departing from the teachings of this disclosure.

A refrigeration cycle of an air conditioner is performed by using a compressor, a condenser, an expansion valve, and an evaporator. A refrigerant undergoes a series of processes involving compression, condensation, expansion, and evaporation. After higher temperature air exchanges heat with a lower temperature refrigerant, low-temperature air is supplied to an indoor room.

The compressor compresses a refrigerant gas in a high-temperature and high-pressure state and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase and heat is released to the surroundings via a condensation process. The expansion valve expands the liquid phase refrigerant in a high-temperature and high-pressure state condensed in the condenser into a liquid phase refrigerant in a low-pressure. The evaporator evaporates the refrigerant expanded in the expansion valve. The evaporator may achieve refrigeration effects via heat exchange with a material to be cooled using latent heat of evaporation of the refrigerant and returns the refrigerant gas in a low-temperature and low-pressure state to the compressor. The air conditioner may adjust temperature of an indoor space throughout this cycle.

An outdoor unit of the air conditioner refers to a part of the refrigeration cycle including a compressor and an outdoor heat exchanger. The expansion valve may be provided in the indoor unit or the outdoor unit and an indoor heat exchanger is located in the air conditioner.

When the indoor space needs to be cooled, the outdoor heat exchanger serves as a condenser and the indoor heat exchanger serves as an evaporator.

When the indoor space needs to be heated, the outdoor heat exchanger serves as an evaporator and the indoor heat exchanger serves as a condenser.

Hereinafter, an indoor unit including an indoor heat exchanger will be referred to as an air conditioner and the indoor heat exchanger will be referred to as a heat exchanger for descriptive convenience.

<FIG> illustrates a top perspective view of an air conditioner according to an embodiment. <FIG> illustrates a bottom perspective view of the air conditioner according to the embodiment. <FIG> illustrates an enlarged view of an air discharge plate according to the embodiment. <FIG> illustrates an exploded view of the air conditioner according to the embodiment.

An air conditioner <NUM> includes housings <NUM> and <NUM> having an inlet port <NUM> and an outlet <NUM>, a heat exchanger <NUM> configured to exchange heat with air flowing into the housings <NUM> and <NUM>, and a blower fan <NUM> configured to circulate air into or out of the housings <NUM> and <NUM>.

A wall-mounted air conditioner <NUM> will be described as an example of the air conditioner <NUM> according to an embodiment, but the embodiment is not limited thereto.

The housings <NUM> and <NUM> may be formed to define the overall appearance of the air conditioner <NUM>. The housings <NUM> and <NUM> may include an air discharge plate <NUM> having a plurality of holes <NUM>. The air discharge plate <NUM> may be disposed on a front surface of the housings <NUM> and <NUM>. The plurality of holes <NUM> may be distinguished from the outlet <NUM>. The plurality of holes <NUM> may be distributed in a predetermined area of the air discharge plate <NUM> as illustrated in <FIG>. However, the embodiment is not limited thereto, and the plurality of holes <NUM> may also be distributed in the entire area of the air discharge plate <NUM>. Air may be discharged out of the housings <NUM> and <NUM> at a low speed through the plurality of holes <NUM> and a plurality of blade holes <NUM> which will be described later. Thus, a user may achieve the purpose of air conditioning with no direct contact with cool air, thereby having enhanced satisfaction.

The housings <NUM> and <NUM> may include a first housing <NUM> defining the front surface of the housings <NUM> and <NUM> and a second housing <NUM> covering a rear surface of the first housing <NUM>.

The first housing <NUM> may have the inlet port <NUM> through which air is introduced and the outlet <NUM> through which the air is discharged. The inlet port <NUM> may be provided at the top surface of the first housing <NUM>. The outlet <NUM> may be provided at the bottom surface of the first housing <NUM>. When the air conditioner <NUM> according to an embodiment is mounted on a wall, the second housing <NUM> faces the wall, and thus the inlet port <NUM> or the outlet <NUM> may be formed in the first housing <NUM>. Meanwhile, the inlet port <NUM> may also be provided at the bottom surface of the first housing <NUM> and the outlet <NUM> may also be provided at the top surface of the first housing <NUM>. The air discharge plate <NUM> may be coupled to the front surface of the first housing <NUM>. The air discharge plate <NUM> is provided to cover the front surface of the first housing <NUM> and may have the plurality of holes <NUM> as described above. In addition, the air discharge plate <NUM> may form a second air flow path <NUM>, which will be described later, together with the first housing <NUM>.

The second housing <NUM> is coupled to the first housing <NUM>. An operating device <NUM> including a fan motor configured to drive a blower fan, a circuit board configured to drive other components of the air conditioner <NUM>, and the like may be provided in one portion of the second housing <NUM>.

The second housing <NUM> may include a first air flow guide <NUM> defining a first air flow path <NUM> which will be described later.

The air conditioner <NUM> includes a blade <NUM> configured to open or close the outlet <NUM>. The blade <NUM> may be rotatably provided at the housings <NUM> and <NUM>. The blade <NUM> may rotate about a rotary shaft <NUM> of the blade <NUM>. The rotary shaft <NUM> of the blade may be located in the housings <NUM> and <NUM>.

The blade <NUM> includes a first blade <NUM> having the plurality of blade holes <NUM> and a second blade <NUM> smaller than the first blade <NUM> and spaced apart from the first blade <NUM>.

The first blade <NUM> has a size corresponding to that of the outlet <NUM>. Thus, the first blade <NUM> closes the outlet <NUM>. In this regard, air may be discharged out of the housings <NUM> and <NUM> through the blade holes <NUM> of the first blade <NUM>. This will be described later.

The second blade <NUM> may not have blade holes. The second blade <NUM> may be provided smaller than the first blade <NUM> and plural in number. Although three second blades <NUM> are provided according to an embodiment, the embodiment is not limited thereto.

The blade <NUM> may move to be located at a first position in which the blade <NUM> closes the outlet <NUM> to discharge air out of the housings <NUM> and <NUM> through the blade holes <NUM> of the first blade <NUM> and the plurality of holes <NUM> of the air discharge plate <NUM> (<FIG>), a second position in which the blade <NUM> opens the outlet <NUM> to guide air discharged through the outlet <NUM> from the blower fan <NUM> straight ahead (<FIG>), or a third position in which the blade <NUM> opens the outlet <NUM> to guide air discharged through the outlet <NUM> from the blower fan <NUM> downward (<FIG>). Hereinafter, an operation mode of the air conditioner <NUM> in the first position is defined as a minimum air volume mode (<FIG>). In addition, an operation mode of the air conditioner <NUM> in the second position is defined as a straight-ahead mode (<FIG>). Also, an operation mode of the air conditioner <NUM> in the third position is defined as a downdraft mode (<FIG>).

The air conditioner <NUM> may control air to be discharged from the blower fan <NUM> through the plurality of holes <NUM> of the air discharge plate <NUM> and the blade holes or directly through the outlet <NUM> by moving the blade <NUM> to be located at the first position (<FIG>), the second position (<FIG>), or the third position (<FIG>).

The blower fan <NUM> may be located in the housings <NUM> and <NUM>. The blower fan <NUM> may be a crossflow fan having the same lengthwise direction as those of the housings <NUM> and <NUM>. The blower fan <NUM> may draw air into the inlet port <NUM> and blow the air to be discharged out of the outlet <NUM>.

The heat exchanger <NUM> may be disposed to cover front and upper portions of the blower fan <NUM>. The heat exchanger <NUM> may be disposed adjacent to the blower fan <NUM>, for example, between the inlet port <NUM> and the blower fan <NUM>. Thus, after external air is introduced into the inlet port <NUM>, the air may be heat-exchanged with the heat exchanger and then discharged out through the outlet <NUM> or the blade holes <NUM> and the air discharge plate <NUM>.

A drain panel <NUM> may be provided below the heat exchanger <NUM> to collect condensed water on the heat exchanger <NUM>. Although not shown in the drawings, the drain panel <NUM> may be connected to a drain hose extending to the outside to drain the condensed water on the heat exchanger <NUM> out of the housings <NUM> and <NUM>.

The drain panel <NUM> may be mounted with a stabilizer <NUM> configured to determine a direction of air blown from the blower fan <NUM>. The stabilizer <NUM> may separate an inflow path of air drawn by the blower fan <NUM> from an outflow path of air discharged therefrom together with the drain panel <NUM>. The stabilizer <NUM> may include a plurality of fins <NUM> to guide air in the transverse direction. The plurality of fins <NUM> may rotate laterally to guide the blown air in the transverse direction.

Also, the stabilizer <NUM> may constitute the first air flow path <NUM> together with the first air flow guide <NUM> which will be described later. The first air flow guide <NUM> may define a lower portion of the first air flow path <NUM> and the stabilizer <NUM> may define an upper portion of the first air flow path <NUM>.

The air conditioner <NUM> may include an air flow guide. The air flow guide is configured to guide air blown from the blower fan <NUM>.

The air flow guide may include the first air flow guide <NUM> and a second air flow guide <NUM>.

The first air flow guide <NUM> is provided to form the first air flow path <NUM> in which air flows from the blower fan <NUM> to the outlet <NUM>. The first air flow path <NUM> may be connected to the outlet <NUM>. The outlet <NUM> may be located at an end of the first air flow guide <NUM>. The outlet <NUM> may be located in a position extended from a flow path of the air guided by the first air flow guide <NUM>.

The second air flow guide <NUM> is provided to form the second air flow path <NUM>. The second air flow path <NUM> may be connected to the plurality of holes <NUM>. Particularly, the second air flow path <NUM> is defined by the second air flow guide <NUM> and an inner surface of the air discharge plate <NUM>. Air flowing in the second air flow path <NUM> may be discharged out of the housings <NUM> and <NUM> through the plurality of holes <NUM> of the air discharge plate <NUM>. The drain panel <NUM> and the stabilizer <NUM> may be located between the first air flow path <NUM> and the second air flow path <NUM>. The drain panel <NUM> and the stabilizer <NUM> may prevent air from entering the heat exchanger <NUM> located above the drain panel <NUM> after passing through the first air flow path <NUM>. When previously heat-exchanged air exchanges heat with the heat exchanger <NUM> again, heat exchange performance may deteriorate. Thus, the drain panel <NUM> and the stabilizer <NUM> may prevent this phenomenon.

<FIG> illustrates a cross-sectional view of an air conditioner according to an embodiment operating in a minimum air volume mode. <FIG> is a cross-sectional view of the air conditioner of <FIG> illustrating amounts of air flows discharged through the air discharge plate and the blade holes. <FIG> illustrates a cross-sectional view of the air conditioner operating in a straight-ahead mode. <FIG> is a diagram schematically illustrating a direction of air discharged by a conventional air conditioner. <FIG> is a diagram schematically illustrating a direction of air discharged by the air conditioner according to the embodiment. <FIG> is a cross-sectional view illustrating a downdraft mode of the air conditioner according to the embodiment.

Hereinafter, the structure and functions of the blade according to an embodiment will be described in more detail with reference to <FIG>.

As illustrated in <FIG>, the air conditioner <NUM> according to an embodiment may operate in the minimum air volume mode, the straight-ahead mode, or the downdraft mode.

The minimum air volume mode refers to an operation state in which the blade <NUM> closes the outlet <NUM>. The straight-ahead mode refers to an operation state in which the blade <NUM> opens the outlet <NUM> and guides air blown from the blower fan straight ahead from the outlet <NUM>. The downdraft mode refers to an operation state in which the blade <NUM> opens the outlet <NUM> and guides air blown from the blower fan downward from the outlet <NUM>. When the air conditioner <NUM> according to the present embodiment operates in the minimum air volume mode, the first blade <NUM> closes the outlet <NUM>. In this case, the second blade <NUM> spaced apart from the first blade <NUM> may guide air blown from the blower fan <NUM> toward the air discharge plate <NUM>. In other words, the second blade <NUM> may guide a part of air having passed through the first air flow path <NUM> toward the second air flow path <NUM>.

Thus, air heat-exchanged by the heat exchanger may be appropriately distributed to the blade holes <NUM> and the plurality of holes <NUM> of the air discharge plate <NUM> and discharged therethrough. Since a convention single blade structure does not include a component guiding heat-exchanged air to an air discharge plate, most of the heat-exchanged air is discharged through blade holes. In this case, the effects of the minimum air volume mode in which heat-exchanged air is discharged through a wide area at a low velocity may not be properly obtained. When most of heat-exchanged air is discharged through the blade holes, a velocity of air passing through the blade holes does not decrease to a level desired by a designer and users may not recognize a difference between a normal wind mode and the minimum air volume mode. Thus, in case of the minimum air volume mode, heat-exchanged air is used to be discharged through not only the blade holes <NUM> but also the plurality of holes <NUM> of the air discharge plate <NUM>. Since the second blade <NUM> guides air inside the housings <NUM> and <NUM> toward the air discharge plate <NUM>, an amount of air discharged out of the housings <NUM> and <NUM> through the plurality of holes <NUM> of the air discharge plate <NUM> increases. Thus, an amount of air discharged through the blade holes <NUM> decreases. As a result, heat-exchanged air is uniformly discharged through a wide area. Thus, the second blade <NUM> may appropriately distribute the air inside the housings <NUM> and <NUM> in the minimum air volume mode to improve the effects of the minimum air volume mode.

According to an embodiment, it may be confirmed that an amount of air discharged through the plurality of holes <NUM> provided in the air discharge plate <NUM> increases based on experimental data. Particularly, although not shown in the drawings, in a conventional single plate structure, an amount of air discharged through a front portion of an air discharge plate accounts for <NUM>% of a total amount of air and an amount of air discharged through a round portion disposed under the air discharge plate accounts for <NUM>% of the total amount of air in a conventional single blade structure. In this case, the amount of air discharged through the blade holes accounts for <NUM>% of the total amount of air.

In a double blade structure according to the embodiment as illustrated in <FIG>, an amount of air discharged through a front portion of the air discharge plat accounts for <NUM>% of a total amount of air an amount of air discharged through a round portion located under the air discharge plate accounts for <NUM>% of the total amount of air, and an amount of air discharged through the blade holes accounts for <NUM>% of the total amount of air which is less than that of the single blade structure by about <NUM>%. Thus, according to the present embodiment, the amount of air discharged respectively through the front portion of the air discharge plate, the round portion, and the blade holes are relatively uniform. That is, the heat-exchanged air may be uniformly discharged through a wider area in comparison with the conventional structure.

As illustrated in <FIG>, when the air conditioner <NUM> operates in the straight-ahead mode, the second blade <NUM> may prevent air from being discharged through the blade holes <NUM> of the first blade <NUM> at a low speed and guide air to be discharged faster and farther forward from the outlet <NUM>.

Heat-exchanged air may be discharged faster and farther through the outlet in the straight-ahead mode unlike the minimum air volume mode. This is because users using the straight-ahead mode are likely to expect faster cooling effects via direct exposure to the heat-exchanged air. Thus, in the straight-ahead mode, the second air flow path <NUM> connected to the air discharge plate <NUM> may be blocked.

According to an embodiment, in the straight-ahead mode, the first blade <NUM> may be disposed to block an airflow toward the second air flow path <NUM>. That is, the first blade <NUM> may be disposed to close the second air flow path <NUM>. Although the blade blocks the second air flow path, the conventional single blade cannot prevent air from flowing through the plurality of blade holes formed in the blade and flowing to the second air flow path, and thus an amount of air discharged through the outlet may decrease.

According to the present embodiment, a second bladed integrated with the first blade <NUM> and rotating together with the first blade <NUM> may be provided. The second blade <NUM> may be located below the first blade <NUM> in the straight-ahead mode. The second blade <NUM> may prevent an ascending air flow toward the first blade <NUM> from flowing into the first blade <NUM>. The second blade <NUM> may guide the ascending air to be discharged straight ahead of the outlet <NUM>. Thus, the amount of air discharged sequentially through the first blade <NUM>, the second air flow path <NUM>, and the plurality of holes <NUM> of the air discharge plate <NUM> may be reduced. Thus, an amount of air discharged through the outlet <NUM> may be increased.

The blade <NUM> may include a connecting blade <NUM> connecting the first blade <NUM> with the second blade <NUM>. The connecting blade <NUM> may be located approximately perpendicular to the first blade <NUM> and the second blade <NUM>. The connecting blade <NUM> and the second blade <NUM> may be provided plural in number and the number of the connecting blade <NUM> may be twice that of the second blade <NUM> to form two side surfaces of the second blade <NUM>. In addition, the plurality of second blades <NUM> may be arranged along a lengthwise direction of the first blade <NUM> and the rotary shaft <NUM> of the blade <NUM> may be located at the connecting blade <NUM>. In this case, the rotary shaft <NUM> may be located closer to a front end of the outlet <NUM> than a rear end of the outlet <NUM>. With this arrangement, the first blade <NUM> may rotate about the rotary shaft <NUM> to close the second air flow path <NUM>.

The first blade <NUM>, the second blade <NUM>, and the connecting blade <NUM> may form an inflow port <NUM> through which air flows in and an outflow port <NUM> through which air flows out. However, the inflow and the outflow of air are defined based on the straight-ahead mode illustrated in <FIG>, and the concept of the inflow port and the outflow port may vary according to arrangement of the blade <NUM>.

As illustrated in <FIG>, the outflow port <NUM> may be smaller than the inflow port <NUM>. In other words, the second blade <NUM> may be aligned to be inclined with respect to the first blade <NUM>. Referring to <FIG>, a distance between the second blade <NUM> and the first blade <NUM> may decrease from one end of the first blade <NUM> located inside the housings <NUM> and <NUM> to the other end of the first blade <NUM> located outside the first blade <NUM>. According to the above-described structure, the outflow port <NUM> is smaller than the inflow port <NUM>. As an area through which air passes increases, a velocity of air decreases in an incompressible flow with a constant density. Thus, a velocity of air discharged out of the outflow port <NUM> is greater than that of air flowing into the inflow port <NUM>. Thus, in the straight-ahead mode, the second blade <NUM> may not only prevent the heat-exchanged air from flowing toward the air discharge plate <NUM> but also guide the heat-exchanged air to be discharged farther forward from the outlet <NUM> at a higher speed.

Referring to <FIG>, a proceeding direction of discharged air may vary according to the presence or absence of the second blade. <FIG> illustrates analysis data of cooling air flows according to the presence or absence of the second blade. Referring to <FIG>, the double blade structure according to the present embodiment has a higher tendency of discharged air to go straight than the conventional single blade structure. In case of the conventional single blade structure, an angle between the horizontal line and the proceeding direction of discharged air is α. In the double blade structure, the angle between a horizontal line and the proceeding direction of discharged air is β. As illustrated in <FIG>, α is greater than β. Since the tendency to go straight is increased as the angle decreases, it is confirmed that the double blade structure has a higher tendency to go straight than the conventional single blade structure.

Referring to <FIG>, the air conditioner <NUM> may operate in the downdraft mode. In general, the downdraft mode may be used for heating operation of the air conditioner <NUM>. Since cool air with a higher density flows down and warm air with a lower density flows up, warm air may be discharged downward during a heating operation. By discharging warm air downward, heat exchange with cool air may be efficiently performed, and thus the entire indoor space may be uniformly heated.

In the case where the rotary shaft <NUM> of the blade <NUM> is located closer to the rear end of the outlet <NUM> than the front end, air discharged through the outlet <NUM> cannot be guided downward even when the blade <NUM> rotates. Since the rotary shaft <NUM> of the blade <NUM> is located closer to the front end of the outlet <NUM> than the rear end according to an embodiment, the blade <NUM> may guide air discharged through the outlet <NUM> downward.

In addition, in case of the conventional single blade structure, although a rotary shaft is located closer to a front end of the outlet and air is guided downward, the heat-exchanged air passes through the blade holes and flows upward. Warm air cannot exchange heat with cool air of the indoor space under the air conditioner and is re-introduced into the inlet. When the warm air is re-introduced into the inlet, heating performance may deteriorate due to a low temperature difference between the re-introduced air and the heat exchanger.

According to the present disclosure, the second blade <NUM> may prevent deterioration of heating performance. Particularly, the second blade <NUM> guides air, which passes through the outlet <NUM> and flows toward the first blade <NUM>, downward, to prevent an air flowing toward the blade holes <NUM> of the first blade <NUM>. Thus, a leaked airflow passing through the blade holes <NUM> may be reduced and deterioration of heating performance may be prevented. That is, heating performance may be improved.

As described above, since the air conditioner <NUM> according to the invention includes the second blade <NUM> spaced apart from the first blade <NUM>, deterioration of heating performance may be prevented, the tendency of discharged air to go straight may be reinforced, and performance of the minimum air volume mode may be improved. Since the second blade <NUM> is integrated with the first blade <NUM> and moves simultaneously with the first blade <NUM>, a separate motor to drive the second blade <NUM> is not required. That is, the aforementioned effects may be obtained by using a simple structure with no additional components.

<FIG> illustrates a bottom perspective view of an air conditioner. <NUM> illustrates a cross-sectional view of the air conditioner operating in a minimum air volume mode. <FIG> illustrates a cross-sectional view of the air conditioner operating in a straight-ahead mode.

Referring to <FIG>, an air conditioner <NUM> not according to the invention will be described.

The air conditioner <NUM> includes housings <NUM> and <NUM> recessed in or mounted on a ceiling C, a heat exchanger <NUM> provided inside the housings <NUM> and <NUM>, and a blower fan (not shown) configured to draw air into the housings <NUM> and <NUM> through an inlet port <NUM> and discharge air out of the housings <NUM> and <NUM> through an air discharge port <NUM>.

The housings <NUM> and <NUM> may have a rectangular box shape opened downward such that components of the air conditioner <NUM> are accommodated therein. The housings <NUM> and <NUM> may include an upper housing <NUM> recessed in the ceiling C and a lower housing <NUM> coupled to lower portions of the upper housing <NUM>. Also, the upper housing <NUM> may not be recessed in the ceiling C but mounted on the ceiling C.

The inlet port <NUM> through which air is sucked may be formed at a central region of the lower housing <NUM> and the air discharge port <NUM> through which air is discharged may formed at outer sides of the inlet port <NUM>.

The air discharge ports <NUM> may be formed adj acent to the respective edges of the lower housing <NUM> to correspond to outer sides thereof. Four air discharge ports <NUM> may be formed. The air discharge ports <NUM> are arranged to discharge air in all directions. According to this structure, the air conditioner <NUM> may suck air from a portion thereunder, cool or heat the air, and discharge the cooled air or heated air downward.

A grille may be coupled to the bottom surface of the lower housing <NUM> to remove dusts from air sucked through the inlet port <NUM>.

The heat exchanger <NUM> may be formed in a rectangular ring and located at an outer portion than the blower fan in the housings <NUM> and <NUM>. The shape of the heat exchanger <NUM> is not limited to the rectangular ring and may also be various shapes such as a circular, an oval, or a polygonal shape.

The air conditioner <NUM> may include a blade <NUM> configured to open or close the air discharge port <NUM>. The blade <NUM> may be provided rotatably about a rotary shaft <NUM>. The blade <NUM> may rotate about the rotary shaft <NUM> to open or close the air discharge port <NUM>.

The blade <NUM> may include a first blade <NUM> having a size corresponding to that of the air discharge port <NUM> and a second blade <NUM> spaced apart from the first blade <NUM>.

The first blade <NUM> may have a plurality of blade holes <NUM> penetrating the first blade <NUM> to allow air to pass therethrough. When the first blade <NUM> closes the air discharge port <NUM>, air blown from the blower fan may be discharged out of the housings <NUM> and <NUM> through the blade holes <NUM>. Since the blade holes <NUM> are far smaller than the air discharge port <NUM>, a velocity of air passing therethrough may considerably decrease. This is defined as minimum air volume mode. In the minimum air volume mode, the velocity of air is very low, and thus a user may not be exposed to direct wind with no cold feelings and uncomfortable feelings.

In the minimum air volume mode, the second blade <NUM> may guide air toward the blade holes <NUM>. The second blade <NUM> may form a flow guide path together with the first blade <NUM> and guide air to the blade holes <NUM>. As the flow guide path is formed, air is guided to the blade holes <NUM> provided adjacent to the other end of the first blade <NUM>. When there is no flow guide, an amount of air flowing toward the blade holes <NUM> located at a far position from the blower fan decreases, and thus most of air is discharged through the blade holes <NUM> located at a predetermined area of the first blade <NUM>. Since the flow guide path is formed, air may be discharged out of the housings <NUM> and <NUM> through the blade holes <NUM> in all areas of the first blade <NUM>.

As illustrated in <FIG>, the blade <NUM> may rotate about the rotary shaft <NUM> to open the air discharge port <NUM>. In this case, since the blade <NUM> does not close the air discharge port <NUM>, air may be discharged directly through the air discharge port. This is defined as a straight-ahead mode.

When the first blade <NUM> opens the air discharge port <NUM>, a first opening <NUM> may be formed between one end of the blade <NUM> closer to the inlet port <NUM> and the lower housing <NUM>. A portion of the lower housing <NUM> forming the first opening <NUM> will be referred to as a first guide portion <NUM>.

When the first blade <NUM> opens the air discharge port <NUM>, a second opening <NUM> may be formed between the other end of the blade <NUM> and the lower housing <NUM>. A portion of the lower housing <NUM> forming the second opening <NUM> will be referred to as second guide portion <NUM>.

The second blade <NUM> may be formed to reduce an amount of air passing through the blade holes <NUM> when the first blade <NUM> opens the air discharge port <NUM>. In addition, the second blade <NUM> may guide air inside the housings <NUM> and <NUM> toward the first opening <NUM> and the second opening <NUM> when the first blade <NUM> opens the air discharge port <NUM>. Thus, an amount of air discharged through the first opening <NUM> and the second opening <NUM> may be increased.

When a conventional single blade opens an air discharge port, air is discharged through the blade holes <NUM> even in the straight-ahead mode. An amount and velocity of air discharged through the first opening <NUM> and the second opening <NUM> are relatively low. Thus, air passing through the first opening <NUM> and the second opening <NUM> is re-introduced through the inlet port <NUM> by the blower fan and condensation occurs on the bottom surfaces of the housings <NUM> and <NUM> in a process of re-introducing cool air through the inlet port <NUM>. When the condensation phenomenon becomes serious, water droplets fall from the air conditioner <NUM> causing uncomfortable feelings to the user. In addition, when the heat-exchanged air does not exchange heat with indoor air but re-introduced into the inlet port, cooling or heating performance may deteriorate due to a low temperature difference between the re-introduced air and the heat exchanger.

The second blade <NUM> spaced apart from the first blade <NUM> may guide the heat-exchanged air to the first opening <NUM> and the second opening <NUM>. In particular, the second blade <NUM> may guide the heat-exchanged air to the second opening <NUM> farther than the first opening <NUM> from the inlet port <NUM>. Thus, an amount of air discharged through the first opening <NUM> and the second opening <NUM> increases and an amount of air discharged through the blade hole <NUM> decreases. Since the amount of air discharged through the first opening <NUM> and the second opening <NUM> increases, the sizes of the first opening <NUM> and the second opening <NUM> are the same, and air has a constant density, a velocity of air passing through the first opening <NUM> and the second opening <NUM> increases. Air discharged through the blade holes <NUM> flows at a lower velocity and has a relatively low tendency to go straight. On the contrary, air guided to the first opening <NUM> and the second opening <NUM> by the second blade <NUM> and discharged through the first opening <NUM> and the second opening <NUM> flows at a higher velocity and a relatively high tendency to go straight. Therefore, most of the heat-exchanged air may be discharged in a direction away from the inlet port through the first opening <NUM> and the second opening <NUM> in the straight-ahead mode.

The first guide portion <NUM> forming the first opening <NUM> together with the first blade <NUM> may guide air such that air discharged through the first opening <NUM> pushes air discharges through the blade holes <NUM> in a direction away from the inlet port <NUM>. Particularly, the first guide portion <NUM> may guide air discharged through the first opening <NUM> to push air discharged through the blade holes <NUM> in a direction away from the inlet port <NUM>. As described above, a velocity of air passing through the first opening <NUM> increases by the second blade <NUM> and is greater than a velocity of air passing through the blade holes <NUM>. Since the velocity of air passing through the first opening <NUM> is greater than that of air passing through the blade holes <NUM> and a direction of air passing through the first opening <NUM> is a direction away from the inlet port <NUM>, air having passed through the blade holes <NUM> is absorbed into air having passed through the first opening <NUM> and flows in the direction away from the inlet port <NUM>. Thus, air is not re-introduced into the inlet port after passing through the blade holes <NUM> or through the first opening <NUM>. When air is re-introduced into the inlet port <NUM> after passing through the blade holes <NUM> or the first opening <NUM> as described above, condensation may occur on the bottom surface of the housings <NUM> and <NUM> and cooling performance may deteriorate. According to present disclosure, re-introduction of air into the inlet port <NUM> is prevented and thus condensation does not occur and cooling performance may not deteriorate.

The second blade <NUM> may be located closer to one end of the first blade <NUM> to increase an amount of air discharged through the second opening <NUM>. Thus, an amount of air discharged through the first opening <NUM> may slightly decrease. However, the amount of air discharged through the second opening <NUM> may further increase and a velocity of air discharged through the second opening <NUM> may also increase. As described above, the heat-exchanged air may be discharged through the second opening <NUM> farther from the inlet port <NUM>. As the amount of air discharged through the second opening <NUM> increases, re-introduction of the heat-exchanged air into the inlet port may be efficiently prevented.

The second blade <NUM> may be integrated with the first blade <NUM> to rotate about the rotary shaft <NUM>. That is, the air conditioner <NUM> does not need separate power to drive the second blade <NUM>. Also, the air conditioner <NUM> may efficiently control air flows by using a simple integrated structure. As described above, the second blade <NUM> may prevent deterioration of cooling performance and condensation by controlling the air flows.

<FIG> illustrates a cross-sectional view of an air conditioner not according to the invention operating in a straight-ahead mode.

Hereinafter, since other components except for the second blade 220a are the same as those described above, and thus detailed descriptions thereof will not be repeated.

Claim 1:
An air conditioner comprising:
a housing (<NUM>, <NUM>) comprising an air discharge plate (<NUM>) that comprises a plurality of holes (<NUM>) and an outlet (<NUM>);
a heat exchanger (<NUM>) located inside the housing;
a blower fan (<NUM>) configured to blow air heat-exchanged with the heat exchanger toward the air discharge plate (<NUM>) or the outlet (<NUM>);
a blade (<NUM>) configured to rotate to be located at (i) a first position to close the outlet (<NUM>), (ii) a second position to open the outlet (<NUM>) to guide air discharged through the outlet (<NUM>) from the blower fan (<NUM>) straight ahead, or (iii) a third position to open the outlet (<NUM>) to guide air discharged through the outlet (<NUM>) from the blower fan (<NUM>) downward,
wherein the blade comprises:
a first blade (<NUM>) comprising a plurality of blade holes and a plate having a size corresponding to that of the outlet (<NUM>), and
a second blade (<NUM>) spaced apart from the first blade,
characterised in that the second blade (<NUM>) is configured to guide air blown from the blower fan toward the air discharge plate (<NUM>) when the first blade (<NUM>) is located at the first position and to guide air passing through the outlet (<NUM>) and flowing towards the first blade (<NUM>) downward to prevent air flowing towards the blade holes (<NUM>) of the first blade (<NUM>) when the blade is located at the third position, and
wherein the blade (<NUM>) is configured to close the outlet (<NUM>) to discharge air out of the housings (<NUM> and <NUM>) through the blade holes (<NUM>) of the first blade (<NUM>) and the plurality of holes (<NUM>) of the air discharge plate (<NUM>) at the first position.