Patent Publication Number: US-11047584-B2

Title: Air conditioner

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. National Stage Application, which claims the benefit under 35 U.S.C. § 371 of PCT International Patent Application No. PCT/KR2016/009246, filed Aug. 22, 2016 which claims the foreign priority benefit under 35 U.S.C. § 119 of Korean Patent Application Nos. 10-2015-0152349 and 10-2015-0160746, filed Oct. 30, 2015 and Nov. 16, 2015, respectively, the contents of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to an air conditioner, and more particularly, to an air conditioner including a circular discharge port. 
     BACKGROUND ART 
     An air conditioner includes a compressor, a condenser, an expansion valve, an evaporator, and a blower fan, and is an apparatus for adjusting a temperature, humidity, airflow and the like of a room using a refrigeration cycle. Air conditioners may be classified into a separate type air conditioner that includes an indoor unit disposed in an indoor space and an outdoor unit disposed in an outdoor space and an all-in-one type air conditioner in which both an indoor unit and an outdoor unit are disposed in a single housing. 
     An air conditioner includes a heat exchanger for exchanging heat between a refrigerant and air, a blower fan for flowing air, and a motor for driving the blower fan, and cools or heats indoor air. 
     The air conditioner may include a discharged airflow controller for discharging air cooled or heated through the heat exchanger in various directions. Generally, the discharged airflow controller includes a vertical or horizontal blade provided at a discharge port and a driver for rotating and driving the blade. That is, an indoor unit of the air conditioner controls a direction of a discharged airflow by adjusting a rotation angle of the blade. 
     According to a discharged airflow control structure using such a blade, an amount of discharged air may decrease due to the airflow interrupted by the blade, and the turbulence generated around the blade may increase flow noise. 
     DISCLOSURE 
     Technical Problem 
     An aspect of the present invention is directed to providing an air conditioner capable of controlling discharged airflow without a blade structure. 
     Technical Solution 
     In accordance with an aspect of an exemplary embodiment, there is provided an air conditioner including a housing including a suction port and a discharge port, a heat exchanger provided inside the housing, a blower fan configured to suction air through the suction port, pass and heat-exchange the air through the heat exchanger, and then discharge the air through the discharge port, and a sub-flow path that suctions and guides some air around the discharge port using a suction force of the blower fan to control the flowing direction of the air discharged from the discharge port. 
     The sub-flow path may include an inlet port configured to suction some of the air around the discharge port and an outlet port configured to discharge the air suctioned through the inlet port to an inside of the housing. 
     The air conditioner may further include an opening/closing control device provided on the sub-flow path and configured to adjust an opening degree of the sub-flow path. 
     The inlet port may be provided at a radially outer side of the discharge port on the discharge port. 
     As the opening/closing control device opens the sub-flow path, a discharge direction of the air discharged through the discharge port may be changed toward the radially outer side of the discharge port. 
     The outlet port may be provided in an upper portion of the housing, which is adjacent to the blower fan. 
     The inlet port may be provided at a radially inner side of the discharge port on the discharge port 
     As the opening/closing control device opens the sub-flow path, a discharge direction of the air discharged through the discharge port may be changed toward the radially inner side of the discharge port. 
     The outlet port may be provided to communicate with the suction port. 
     The blower fan may suction air from both sides thereof in a direction of rotation axis of the blower fan and discharge the air in a radial direction of the blower fan. 
     The blower fan may be configured such that one side of the blower fan in a direction of rotation axis of the blower fan faces the suction port and the other side opposite to the one side faces the outlet port. 
     In accordance with an aspect of another exemplary embodiment, there is provided an air conditioner including a housing including a main flow path that connects a suction port and a discharge port, a heat exchanger provided on the main flow path, a blower fan configured to suction air through the suction port, pass and heat-exchange the air through the heat exchanger, and then discharge the air through the discharge port, and a sub-flow path branched off from the main flow path, wherein some air blown by the blower fan is discharged through the sub-flow path toward the discharge port in a different direction from a direction of air discharged through the main flow path. 
     The air conditioner may further include an opening/closing control device provided on the sub-flow path and configured to adjust an opening degree of the sub-flow path. 
     The sub-flow path may be provided such that some of the air blown by the blower fan is branched off from the main flow path before passing through the heat exchanger. 
     The sub-flow path may discharge some of the air blown by the blower fan in a radially inner side of the discharge port. 
     As the opening/closing control device opens the sub-flow path, a discharge direction of the air discharged through the discharge port may be changed toward the radially outer side of the discharge port. 
     The sub-flow path may discharge air from a radially outer side of the discharge port. 
     As the opening/closing control device opens the sub-flow path, a discharge direction of the air discharged through the discharge port may be changed toward the radially inner side of the discharge port. 
     In accordance with an aspect of still another exemplary embodiment, there is provided an air conditioner including a housing including a main flow path that connects a suction port and a discharge port, a heat exchanger provided on the main flow path, a blower fan provided on the main flow path to flow air, a sub-flow path provided separately from the main flow path, one end of the sub-flow path adjacent to the discharge port, and the other end adjacent to the blowing fan, an opening/closing control device provided on the sub-flow path and configured to adjust an opening degree of the sub-flow path. 
     The other end of the sub-flow path is adjacent to a portion of the blower fan where air is sucked, when the opening/closing control device opens the sub-flow path, a part of the air around the discharge port may be sucked into the sub-flow path by a suction force of the blower fan, and the discharge direction of the air discharged from discharge port may be changed. 
     The other end of the sub-flow path is adjacent to a portion of the blower fan where air is discharged, when the opening/closing control device opens the sub-flow path, a part of the air blown by the blower fan may be discharged toward the discharge port through the sub-flow path, and discharge direction of the air discharged from the discharge port may be changed by the air discharged through the sub-flow path. 
     In accordance with an aspect of still another exemplary embodiment, there is provided an air conditioner including a housing including a main flow path that connects a suction port and a discharge port, a heat exchanger provided on the main flow path, a blower fan configured to suction air through the suction port, pass and heat-exchange the air through the heat exchanger, and then discharge the air through the discharge port, and a sub-flow path branched off from the main flow path, wherein the sub-flow path is configured to switch the discharge direction of the air discharged from the discharge port to the air discharged through the sub-flow path. 
     The air conditioner may further include an opening/closing control device provided on the sub-flow path and configured to adjust an opening degree of the sub-flow path. 
     The sub-flow path may discharge air in a direction different from the direction of the air discharged from the discharge port. 
     The sub-flow path may be configured to discharge air inside the radial direction of the discharge port, the air discharged through the sub-flow path may switch the discharge direction of the air discharged from the discharge port toward the radially inner side of the discharge port. 
     The sub-flow path may be configured to discharge air outside the radial direction of the discharge port, the air discharged through the sub-flow path may switch the discharge direction of the air discharged from the discharge port toward the radially outer side of the discharge port. 
     Advantageous Effects 
     According to the spirit of the present invention, an air conditioner can suction air around a discharge port without a blade to control discharged airflow. 
     According to the spirit of the present invention, an air conditioner can control discharged airflow with a relatively simple structure to reduce a product cost. 
     According to the spirit of the present invention, an air conditioner can decrease a reduction of an amount of discharged airflow due to an interruption by a blade because the air conditioner controls the discharged airflow without the blade. 
     According to the spirit of the present invention, an air conditioner can reduce flow noise because the air conditioner controls discharged airflow without a blade. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  illustrates a perspective view of an air conditioner according to an exemplary embodiment of the present invention. 
         FIG. 2  illustrates a bottom view of the air conditioner shown in  FIG. 1 . 
         FIG. 3  illustrates a cross-sectional view of the air conditioner according to the exemplary embodiment of the present invention, which is taken along line I-I of  FIG. 2 . 
         FIG. 4  illustrates an expanded view of portion O shown in  FIG. 3 . 
         FIG. 5  illustrates a block diagram of a control system of the air conditioner shown in  FIG. 1 . 
         FIG. 6  illustrates a cross-sectional view of an air conditioner according to another exemplary embodiment of the present invention. 
         FIG. 7  illustrates a cross-sectional view of an air conditioner according to still another exemplary embodiment of the present invention. 
         FIG. 8  illustrates a cross-sectional view of an air conditioner according to yet another exemplary embodiment of the present invention. 
         FIG. 9  illustrates a cross-sectional view of an air conditioner according to yet another exemplary embodiment of the present invention. 
         FIG. 10  illustrates a cross-sectional view of an air conditioner according to yet another exemplary embodiment of the present invention. 
         FIG. 11  illustrates a cross-sectional view of an air conditioner according to yet another exemplary embodiment of the present invention. 
     
    
    
     MODES OF THE INVENTION 
     Exemplary embodiments described in the specification and configurations shown in the drawings are merely examples of preferred embodiments of the present invention, and various modifications may exist at the time of filing of the present application to replace the exemplary embodiments and drawings of the specification. 
     In addition, the same reference numerals or symbols given in the drawings of the specification indicate parts or elements that perform substantially a same function. 
     Also, terms used in the specification are used to illustrate the exemplary embodiments and are not intended to limit and/or define the disclosed invention. Singular forms include plural referents unless the context clearly dictates otherwise. In this specification, the terms “comprises” or “having” and the like are used to specify that there is a stated feature, number, step, operation, element, part, or a combination thereof but do not preclude the presence or addition of one or more features, integers, steps, operations, elements, parts, or combinations thereof. 
     It is also to be understood that terms including ordinals such as “first,” “second,” and the like used in the specification may be used to describe various elements, but the elements are not limited by the terms and the terms are used only to distinguish an element from another. For instance, a first element may be referred to as a second element without departing from the scope of the present invention, and similarly, a second element may be referred to as a first element. The term “and/or” includes any combination of a plurality of related listed items and any of a plurality of related listed items. 
     Meanwhile, the terms “front end,” “rear end,” “upper portion,” “lower portion,” “upper end,” and “lower end” used in the following description are defined with reference to the drawings, but do not limit a shape and location of each element. 
     Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the appended drawings. 
       FIG. 1  illustrates a perspective view of an air conditioner according to an exemplary embodiment of the present invention.  FIG. 2  illustrates a bottom view of the air conditioner shown in  FIG. 1 .  FIG. 3  illustrates a cross-sectional view of the air conditioner according to the exemplary embodiment of the present invention, which is taken along line I-I of  FIG. 2 .  FIG. 4  illustrates an expanded view of portion O shown in  FIG. 3 .  FIG. 5  illustrates a block diagram of a control system of the air conditioner shown in  FIG. 1 . 
     An air conditioner  1  according to the exemplary embodiment of the present invention will be described with reference to  FIGS. 1 to 5 . 
     The air conditioner  1  may be installed on a ceiling C. A part of the air conditioner  1  may be buried in the ceiling C. 
     The air conditioner  1  may include a housing  10  including a suction port  20  and a discharge port  21 , a heat exchanger  30  provided within the housing  10 , and a blower fan  40  configured to flow air. 
     The housing  10  may have an approximately circular shape when viewed from above. The housing  10  may include an upper housing  11  disposed within the ceiling C, an intermediate housing  12  coupled to a lower portion of the upper housing  11 , and a lower housing  13  coupled to a lower portion of the intermediate housing  12 . 
     The suction port  20  through which air is suctioned may be formed in a central portion of the lower housing  13 , and the discharge port  21  through which air is discharged may be formed on a radially outer side of the suction port  20 . The discharge port  21  may have an approximately circular shape when viewed from above. 
     With such a structure, the air conditioner  1  may suction air from a lower portion thereof, cool and heat the air, and discharge the air back to the lower portion. 
     The lower housing  13  may include a first guide surface  14   a  and a second guide surface  14   b  forming the discharge port  21 . The first guide surface  14   a  may be provided adjacent to the suction port  20 , and the second guide surface  14   b  may be provided more spaced apart from the suction port  20  than the first guide surface  14   a . In other words, the first guide surface  14   a  may be provided at a radially inner side of the discharge port  21 , and the second guide surface  14   b  may be provided on a radially outer side of the discharge port  21 . The first guide surface  14   a  and/or the second guide surface  14   b  may include a Coanda curved surface portion that guides air discharged through the discharge port  21 . The Coanda curved surface portion may induce airflow discharged through the discharge port  21  to flow in a close contact with the Coanda curved surface portion. 
     A grille  15  may be coupled to a lower surface of the lower housing  13  to filter dust from air suctioned into the suction port  20 . 
     The heat exchanger  30  may be provided inside the housing  10  and disposed on a flow path of air between the suction port  20  and the discharge port  21 . The heat exchanger  30  may include a tube (not shown) through which a refrigerant flows and a header (not shown) connected to an external refrigerant tube to supply the refrigerant to the tube or retrieve the refrigerant from the tube. A heat exchange fin (not shown) may be provided on the tube to increase a heat dissipation area. 
     The heat exchanger  30  may have an approximately circular shape when viewed from above. The heat exchanger  30  is disposed on a drain tray  16  so that condensate water generated in the heat exchanger  30  may be collected in the drain tray  16 . 
     The blower fan  40  may be provided on a radially inner side of the heat exchanger  30 . The blower fan  40  may be a centrifugal fan that suctions air in an axial direction thereof and discharges the air in a radial direction thereof. Further, the blower fan  40  may be provided with a rotation center at an approximately central portion in the axial direction so that air can be suctioned from both sides in the axial direction. A blowing motor  41  for driving the blower fan  40  may be provided at the air conditioner  1 . 
     With such a configuration, the air conditioner  1  may suction and cool air in a room and then discharge the air to the room, or may suction and heat the air in the room and then discharge the air to the room. 
     The air conditioner  1  may further include a heat exchanger pipe  81  connected to the heat exchanger  30 , through which the refrigerant flows, and a drain pump  82  for discharging condensed water collected in the drain tray  16  to the outside. The heat exchanger pipe  81  and the drain pump  82  may be provided on an upper portion of a bridge  80  to be described below so as not to block the suction port. Specifically, the heat exchanger pipe  81  may be seated on a heat exchanger pipe seat portion  16   a  provided in the drain tray  16 , and the drain pump  82  may be seated on a drain pump seat portion  16   b.    
     Referring to  FIG. 2 , the air conditioner  1  may be provided adjacent to the discharge port  21  and further include the bridge  80  extending in a circumferential direction of the discharge port  21  by a predetermined length. Three bridges  80  may be provided to be spaced a predetermined interval from each other in the circumferential direction. The bridge  80  may be provided to connect the first guide surface  14   a  with the second guide surface  14   b.    
     When the discharge port  21  is provided in a circular shape and air is discharged in all directions, a relatively high pressure is formed around the discharge port  21  and a relatively low pressure is formed around the suction port  20 . In addition, since air is discharged in all directions of the discharge port  21  and forms an air curtain, air to be suctioned through the suction port  20  cannot be supplied toward the suction port  20 . In this situation, the air discharged from the discharge port  21  is suctioned through the suction port  20  again, the re-suctioned air causes dew condensation inside the housing  10 , and the air to be discharged is lost, which degrades a perceived performance. 
     The bridge  80  according to the exemplary embodiment of the present invention is provided over the discharge port  21  and blocks the discharge port  21  by a predetermined length. Accordingly, the discharge port  21  is divided into a first section S 1  in which air is discharged and a second section S 2  in which air is hardly discharged because the air is blocked by the bridge  80 . That is, the bridge  80  may form the second section S 2  through which air to be suctioned through the suction port  20  is supplied. Further, the bridge  80  may reduce a pressure difference between a low pressure around the suction port  20  and a high pressure around the discharge port  21  so that the air can be smoothly supplied to the suction port  20 . 
     The bridge  80  may include a pair of discharge guide surfaces  80   a  getting closer to each other as the discharge guide surfaces  80   a  get closer to a direction in which air is discharged so as to minimize the second section S 2  formed by the bridge  80 . The air discharged from the discharge port  21  by the discharge guide surfaces  80   a  may be more widely spread and discharged from the discharge port  21 . 
     The air conditioner  1  shown in  FIG. 2  has three bridges  80  arranged at equal intervals, that is, at an angle of 120°, but the air conditioner  1  is not limited thereto and may have one bridge, two bridges arranged at an angle of 180°, or more than four bridges arranged to be spaced apart from each other in the circumferential direction of the discharge port  21 . That is, the number of bridges and the angle at which the bridges are disposed are not limited. 
     Further, when a plurality of bridges  80  are provided, a display unit  85  may be disposed under one bridge  80  of the plurality of bridges  80 . The display unit  85  may display an operating state of the air conditioner  1  to a user. Specifically, the display unit  85  may display whether the air conditioner  1  is operating, a direction of discharged airflow, or whether the air conditioner  1  is operating in a cooling mode or in a heating mode, but is not limited thereto and various information related to the air conditioner  1  may be displayed. In addition to the display unit  85 , although not shown in the drawings, at least one of a remote control receiver unit (not shown), an input unit (not shown) of the air conditioner  1 , and a communication unit (not shown) configured to communicate with an external device may be provided under the bridge  80 . 
     The air discharged through the discharge port  21  may be spread and discharged to cool or heat the room by the bridge  80  without being suctioned into the suction port  20  again. 
     The air conditioner  1  may further include a sub-flow path  101  that suctions some of the air around the discharge port  21  to control the discharged airflow. Here, the control of the discharged airflow means to control a direction of the discharged airflow, that is, the discharge angle of the air discharged through the discharge port  21 . 
     The sub-flow path  101  may be provided around the discharge port  21  and connect an inlet port  102  through which some of the air around the discharge port  21  flows and an outlet port  103  through which the air flowing in the inlet port  102  is discharged to an inside of the housing  10 . The sub-flow path  101  may be provided along an outer surface of the upper housing  11  on an outer side of the upper housing  11 . Alternatively, the sub-flow path  101  may be provided within the housing  10 . 
     The sub-flow path  101  may include a first flow path  101   a , which is formed outside the housing  10  and in a circumferential direction of the housing  10  and communicates with the inlet port  102 , and a second flow path  101   b  extending from the first flow path  101   a  to an upper surface of the housing  10 . Air suctioned through the inlet port  102  may be discharged to the inside of the housing  10  through the outlet port  103  via the first flow path  101   a  and second flow path  101   b . However, the above structure of the sub-flow path  101  is merely given as an example, the sub-flow path  101  is sufficient only to connect the inlet port  102  and the outlet port  103 , and the structure, shape, and arrangement thereof are not limited. 
     The inlet port  102  may be formed in the second guide surface  14   b  provided at the radially outer side of the discharge port  21 . The outlet port  103  may be formed in an upper surface of the upper housing  11 . Specifically, the outlet port  103  may be formed above the blower fan  40 . The outlet port  103  may be formed in the upper surface of the upper housing  11  adjacent to the rotation center of the blower fan  40 . In this case, the blower fan  40  may be configured to suction air from both the lower side at which the suction port  20  is provided and the upper side at which the outlet port  103  is provided and to discharge the air in a radial direction of the blower fan  40 , as described above. 
     According to such a configuration, some of the air around the discharge port  21  may be suctioned through the inlet port  102  by suction force of the blower fan  40 , pass through the sub-flow path  101 , and then be discharged through the outlet port  103 . A flow direction of the air discharged from the discharge port  21  may be changed as some of the air around the discharge port  21  is suctioned into the sub-flow path  101  through the inlet port  102 . In this case, the suction force of the blower fan  40  may be adjusted by adjusting a rotational speed of the blower fan  40 , and an amount of air that can be suctioned through the inlet port  102  may be adjusted accordingly. In addition, as the amount of the air suctioned through the inlet port  102  is adjusted, the flow direction of the air discharged from the discharge port  21  may also be gradually changed. 
     An opening/closing control device  104  capable of adjusting an opening degree of the sub-flow path  101  may be provided on the sub-flow path  101 . 
     The opening/closing control device  104  may be a switch capable of selectively opening the sub-flow path  101 . The opening/closing control device  104  may be a damper. The opening/closing control device  104  may be disposed adjacent to the blower fan  40  on the sub-flow path  101 . The opening/closing control device  104  may allow the air around the discharge port  21  to be selectively suctioned through the inlet port  102  by selectively opening the sub-flow path  101 . 
     Specifically, referring to  FIG. 4 , when the opening/closing control device  104  does not open the sub-flow path  101 , a suction force of the blower fan  40  is not delivered to the inlet port  102 . Accordingly, the air around the discharge port  21  is not suctioned into the inlet port  102 , and discharged airflow is formed in a direction A 1 . Conversely, when the opening/closing control device  104  opens the sub-flow path  101 , the suction force of the blower fan  40  is delivered to the inlet port  102 . Thus, the air around the discharge port  21  is suctioned into the inlet port  102 , and the discharged airflow is formed in a direction A 2 . In other words, since a flow direction of the discharged airflow is changed to the radially outer side of the discharge port  21  so that the discharged airflow may be widely spread. 
     In addition, the opening/closing control device  104  may adjust an amount of the air around the discharge port  21  that is suctioned through the inlet port  102  by adjusting the opening degree of the sub-flow path  101 . Further, as the amount of the air around the discharge port  21  that is suctioned through the inlet port  102  is adjusted, a degree of direction change of the air discharged from the discharge port  21  may be adjusted. 
     Specifically, referring to  FIG. 5 , when a user inputs a command to a control unit  91  to fully open the opening/closing control device  104  through an input unit  90 , the control unit  91  may control the opening/closing control device  104  to fully open the sub-flow path  101  and the air discharged through the discharge port  21  accordingly spreads as much as possible toward the radially outer side of the discharge port  21 . That is, the discharged airflow may be formed in the direction A 2 . 
     In contrast, when the user inputs a command to the control unit  91  to partially open the opening/closing control device  104  through the input unit  90 , the control unit  91  controls the opening/closing control device  104  to open only a part of the sub-flow path  101 , and the air discharged through the discharge port  21  accordingly less spreads toward the radially outer side of the discharge port  21  than in the direction A 2 . That is, the discharged airflow may be formed in a direction between the direction A 2  and the direction A 1 . 
     It is apparent to a person of ordinary skill in the art that the discharged airflow may be formed in any direction by more finely controlling an opening degree of the opening/closing control device  104 . 
     With such a configuration, the air conditioner  1  according to the exemplary embodiment of the present invention may control the discharged airflow without a blade structure, as compared with the conventional structure in which a blade is provided in the discharge port  21  and the discharged airflow is controlled by the rotation of the blade. Accordingly, since there is no interruption by the blade, the discharge amount can be increased and the flow noise can be reduced. 
       FIG. 6  illustrates a cross-sectional view of an air conditioner  2  according to another exemplary embodiment of the present invention. The air conditioner  2  according to another exemplary embodiment of the present invention will be described with reference to  FIG. 6 . However, the same reference symbols will be assigned to the same components as those in the exemplary embodiment shown in  FIG. 4 , and the description thereof will be omitted. 
     A sub-flow path  201  of the air conditioner  2  may be provided in the lower housing  13 . Specifically, an inlet port  202  may be formed in the first guide surface  14   a  provided at the radially inner side of the discharge port  21 . An outlet port  203  may be provided in the suction port  20  to communicate with the suction port  20 . As the outlet port  203  communicates with the suction port  20 , suction force generated at the suction port  20  of the blower fan  40  may be delivered to the sub-flow path  201  such that the inlet port  202  may suction air around the discharge port  21 . 
     The sub-flow path  201  is formed to connect the inlet port  202  and the outlet port  203 . The sub-flow path  201  may include a first flow path  201   a , which extends in a circumferential direction thereof and communicates with the inlet port  202 , and a second flow path  201   b  extending from the first flow path  201   a  toward the radially inner side of the discharge port  21 . Accordingly, the air suctioned through the inlet port  202  may pass through the first flow path  201   a  and the second flow path  201   b  and be discharged through the outlet port  203 . However, such a structure of the sub-flow path  201  is merely given as an example, the sub-flow path  201  is sufficient only to connect the inlet port  202  and the outlet port  203 , and the structure, shape, and arrangement thereof are not limited. 
     In addition, the sub-flow path  201  may extend by a predetermined length in the circumferential direction of the discharge port  21 . The sub-flow path  201  may be provided to be spaced apart from each other in the circumferential direction of the discharge port  21  and be provided in plural. 
     According to such a configuration, the air conditioner  2  may suction the air around the discharge port  21  through the inlet port  202  formed in the first guide surface  14   a  using the suction force of the blower fan  40 , and discharge the air to the inside of the housing  10  through the outlet port  203  formed at the side of the suction port  20 . 
     Specifically, when an opening/closing control device  204  does not open the sub-flow path  201 , the suction force of the blower fan  40  is not delivered to the inlet port  202 . Therefore, the air around the discharge port  21  is not suctioned into the inlet port  202 , and the air discharged through the discharge port  21  is discharged in the direction A 1 . On the other hand, when the opening/closing control device  204  opens the sub-flow path  201 , the suction force of the blower fan  40  is delivered to the inlet port  202 . Thus, some of the air around the discharge port  21  is suctioned into the sub-flow path  201  through the inlet port  202 , and the air discharged through the discharge port  21  is discharged in the direction A 2 . In other words, the direction of the discharged airflow is changed to the radially inner side of the discharge port  21 . 
     In addition, as shown in  FIG. 4 , the opening/closing control device  204  may adjust the amount of the air around the discharge port  21 , which is suctioned through the inlet port  202 , by adjusting an opening degree of the sub-flow path  201 . As the amount of the air around the discharge port  21  suctioned through the inlet port  202  is adjusted, the degree of direction change of air discharged through the discharge port  21  may be adjusted. 
     Specifically, when the opening/closing control device  204  fully opens the sub-flow path  201 , the discharged airflow may be collected as much as possible toward the radially inner side of the discharge port  21  since the amount of the air around the discharge port  21  suctioned through the inlet port  202  is maximized. That is, the discharged airflow may be formed in the direction A 2 . 
     Conversely, when the opening/closing control device  204  partially opens the sub-flow path  201 , the discharged airflow is less collected toward the radially inner side of the discharge port  21  than in the direction A 2  since the amount of the air around the discharge port  21  suctioned through the inlet port  202  is small. That is, the discharged airflow may be formed in a direction between the direction A 1  and the direction A 2 . 
     It is apparent to a person of ordinary skill in the art that the discharged airflow can be formed in any direction by more finely controlling an opening degree of the opening/closing control device  204 . 
       FIG. 7  illustrates a cross-sectional view of an air conditioner  3  according to still another exemplary embodiment of the present invention. The air conditioner  3  according to still another exemplary embodiment of the present invention will be described with reference to  FIG. 7 . However, the same reference symbols will be assigned to the same components as those in the exemplary embodiments described above, and the description thereof will be omitted. 
     The air conditioner  3  may control the discharged airflow by bypassing some of the air blown by the blower fan  40  to a sub-flow path  301  and then discharging the air in a direction different from that of the air discharged through from the discharge port  21 . For this purpose, the air conditioner  3  includes the sub-flow path  301  branched from a main flow path P. The sub-flow path  301  may be provided such that the air blown from the blower fan  40  is branched off from the main flow path P before passing through the heat exchanger  30 . 
     The sub-flow path  301  may connect an inlet port  302  through which some air flowing in the main flow path P flows and an outlet port  303  through which the air introduced through the inlet port  302  is discharged. The sub-flow path  301  may be formed by the intermediate housing  12  and the lower housing  13 . The sub-flow path  301  may be provided at the radially inner side of the discharge port  21 . The sub-flow path  301  may include a first flow path  301   a  communicating with the inlet port  302  and a second flow path  301   b  that connects the first flow path  301   a  with the outlet port  303  and extends in a circumferential direction thereof. Accordingly, the air introduced through the inlet port  302  may pass through the first flow path  301   a  and the second flow path  301   b  and be discharged through the outlet port  303 . Specifically, the air passing through the first flow path  301   a  flows into the entire second flow path  301   b  extending in the circumferential direction, and then is discharged through the outlet port  303 . However, the structure of the sub-flow path  301  is given as only an example, the sub-flow path  301  is sufficient only to connect the inlet port  302  and the outlet port  303 , and the structure, shape, and arrangement of the sub-flow path  301  are not limited. 
     The inlet port  302  may be provided on the main flow path P between the blower fan  40  and the heat exchanger  30 . Accordingly, some of the air blown by the blower fan  40  may be introduced into the sub-flow path  301  through the inlet port  302 . The inlet port  302  may be provided in the drain tray  16 . 
     The outlet port  303  may be formed in the first guide surface  14   a  provided at the radially inner side of the discharge port  21 . The outlet port  303  discharges air in a direction different from the flow direction of the air discharged through the discharge port  21 . Specifically, the flow direction of the air discharged through the outlet port  303  after passing through the sub-flow path  301  may be formed further toward the radially outer side of the discharge port  21  than the flow direction of the air discharged through the discharge port  21  after passing through the main flow path P. According to such a configuration, the air that is discharged through the outlet port  303  after passing through the sub-flow path  301  may push the air, which is discharged through the discharge port  21  after passing through the main flow path P, toward the radially outer side of the discharge port  21 . 
     An opening/closing control device  304  configured to adjust an opening degree of the sub-flow path  301  may be provided on the sub-flow path  301  adjacent to the inlet port  302 . 
     With such a configuration, the air conditioner  3  may change the discharge direction of the air discharged through the discharge port  21 . 
     Specifically, when the opening/closing control device  304  does not open the sub-flow path  301 , all of the air blown by the blower fan  40  passes through the heat exchanger  30  and is then discharged from the main flow path P and the discharge port  21  in the direction A 1 . 
     Conversely, when the opening/closing control device  304  opens the sub-flow path  301 , some of the air blown by the blower fan  40  is branched off from an upstream of the main flow path P into the sub-flow path  301  before passing through the heat exchanger  30 . The air introduced into the sub-flow path  301  pushes the air, which is discharged through the discharge port  21  through the outlet port  303 , toward the radially outer side of the discharge port  21  and is discharged. In other words, the flow direction of the air discharged through the discharge port  21  is changed to the direction A 2 . Accordingly, the discharged airflow may be spread widely. 
     In addition, as in the above-described exemplary embodiments, the opening/closing control device  304  may adjust an amount of the air, which is discharged through the outlet port  303  after passing through the sub-flow path  301 , by adjusting the opening degree of the sub-flow path  301 . Further, the degree of flow direction change of the air discharged through the discharge port  21  may be adjusted by adjusting the amount of the air discharged through the outlet port  303 . 
     Specifically, when the opening/closing control device  304  fully opens the sub-flow path  301 , the amount of the air discharged through the outlet port  303  through the sub-flow path  301  is maximized, and the air discharged through the discharge port  21  is accordingly spread as much as possible toward the radially outer side of the discharge port  21 . That is, the discharged airflow may be formed in the direction A 2 . 
     On the other hand, when the opening/closing control device  304  partially opens the sub-flow path  301 , the amount of the air discharged through the outlet port  303  through the sub-flow path  301  is small and the air discharged through the discharge port  21  is accordingly less spread toward the radially outer side of the discharge port  21  than in the direction A 2 . That is, the discharged airflow may be formed in a direction between the direction A 1  and the direction A 2 . 
     It is apparent to a person of ordinary skill in the art that the discharged airflow can be formed in any direction by more finely controlling an opening degree of the opening/closing control device  304 . 
       FIG. 8  illustrates a cross-sectional view of an air conditioner  4  according to yet another exemplary embodiment of the present invention. The air conditioner  4  according to yet another exemplary embodiment of the present invention will be described with reference to  FIG. 8 . However, the same reference symbols will be assigned to the same components as those in the exemplary embodiments described above, and the description thereof will be omitted. 
     The air conditioner  4  may control the discharged airflow by bypassing some of the air blown by the blower fan  40  to a sub-flow path  401  and then discharging the air in a direction different from that of the air discharged through the discharge port  21 . In this case, the sub-flow path  401  may be provided such that the air blown by the blower fan  40  is branched off from the main flow path P after passing through the heat exchanger  30 . 
     The sub-flow path  401  may connect an inlet port  402  and an outlet port  403 . The sub-flow path  401  may be formed along an outer wall of the housing  10  using a separate duct, or formed inside the housing  10 . 
     The sub-flow path  401  may include a first flow path  401   a  communicating with the inlet port  402  and a second flow path  401   b  that connects the first flow path  401   a  and the outlet port  403  and extends in a circumferential direction thereof. Accordingly, the air introduced through the inlet port  402  may pass through the first flow path  401   a  and second flow path  401   b  and then be discharged through the outlet port  403 . Specifically, the air passing through the first flow path  401   a  flows through the entire second flow path  401   b  extending in the circumferential direction and then discharged through the outlet port  403 . However, such a structure of the sub-flow path  401  is given as only an example, the sub-flow path  401  is sufficient only to connect the inlet port  402  and the outlet port  403 , and the structure, shape, and arrangement thereof are not limited. 
     The inlet port  402  may be provided on the main flow path P between the heat exchanger  30  and the discharge port  21 . Accordingly, some of the air that is blown by the blower fan  40  and passes through the heat exchanger  30  may be introduced into the sub-flow path  401  through the inlet port  402 . The inlet port  402  may be provided in the upper housing  11 . 
     The outlet port  403  may be formed in the second guide surface  14   b  provided on the radially outer side of the discharge port  21 . The outlet port  403  discharges air in a different direction from the flow direction of the air discharged through the discharge port  21 . Specifically, the flow direction of the air discharged through the outlet port  403  after passing through the sub-flow path  401  may be formed further toward the radially inner side of the discharge port  21  than the flow direction of the air discharged through the discharge port  21  after passing through the main flow path P. According to such a configuration, the air discharged through the outlet port  403  after passing through the sub-flow path  401  may push the air, which is discharged through the discharge port  21  after passing through the main flow path P, toward the radially inner side of the discharge port  21 . 
     An opening/closing control device  404  configured to adjust an opening degree of the sub-flow path  401  may be provided on the sub-flow path  401  adjacent to the inlet port  402 . 
     With such a configuration, the air conditioner  4  may change the discharge direction of the air discharged through the discharge port  21 . 
     Specifically, when the opening/closing control device  404  does not open the sub-flow path  401 , the air blown by the blower fan  40  passes through the heat exchanger  30  and is then fully discharged through the main flow path P and the discharge port  21  in the direction A 1 . 
     On the other hand, when the opening/closing control device  404  opens the sub-flow path  401 , some of the air blown by the blower fan  40  passes through the heat exchanger  30  and is then branched off toward the sub-flow path  401 . The air introduced into the sub-flow path  401  pushes the air discharged through the discharge port  21  through the outlet port  403  toward the radially inner side of the discharge port  21 , and is discharged. That is, the flow direction of the air discharged through the discharge port  21  is changed to the direction A 2 . Accordingly, the discharged airflow may be formed in an approximately vertical direction. 
     In addition, as in the above-described exemplary embodiments, the opening/closing control device  404  may adjust an amount of the air, which is discharged through the outlet port  403  after passing through the sub-flow path  401 , by adjusting the opening degree of the sub-flow path  401 . Further, the degree of flow direction change of the air discharged through the discharge port  21  may be adjusted by adjusting the amount of the air discharged through the outlet port  403 . 
     Specifically, when the opening/closing control device  404  fully opens the sub-flow path  401 , the amount of the air passing through the sub-flow path  401  increases. Accordingly, since the air discharged through the outlet port  403  strongly pushes and discharges the air discharged through the discharge port  21  in a vertical direction, the discharged airflow is collected as much as possible toward the radially inner side of the discharge port  21 . Conversely, when the opening/closing control device  404  partially opens the sub-flow path  401 , the amount of the air passing through the sub-flow path  401  decreases. Accordingly, since the force that the air discharged through the outlet port  403  pushes out the air discharged through the discharge port  21  decreases, the discharged airflow is collected a small amount toward the radially inner side of the discharge port  21 . That is, the discharged airflow may be formed in a direction between the direction A 1  and the direction A 2 . 
     It is apparent to a person of ordinary skill in the art that the discharged airflow can be formed in any direction by more finely controlling an opening degree of the opening/closing control device  404 . 
       FIG. 9  illustrates a cross-sectional view of an air conditioner  5  according to yet another exemplary embodiment of the present invention. The air conditioner  5  according to yet another exemplary embodiment of the present invention will be described with reference to  FIG. 9 . However, the same reference symbols will be assigned to the same components as those in the exemplary embodiments described above, and the description thereof will be omitted. 
     The air conditioner  5  may control the discharged airflow by bypassing some of the air blown by the blower fan  40  to a sub-flow path  501  and then discharging the air in a direction different from that of the air discharged through the discharge port  21 . On the other hand, the sub-flow path  501  may control the discharged airflow by discharging the air in a direction similar to that of the air discharged through the discharge port  21 . For the purpose, the air conditioner  5  includes the sub-flow path  501  branched off from the main flow path P. The sub-flow path  501  may be provided such that the air blown by the blower fan  40  is branched off from the main flow path P before passing through the heat exchanger  30 . 
     The sub-flow path  501  may connect an inlet port  502  through which some of the air flowing through the main flow path P is introduced and an outlet port  503  through which the air introduced through the inlet port  502  is discharged. The sub-flow path  501  may be provided at the radially inner side of the discharge port  21 . The sub-flow path  501  may include a first flow path  501   a  communicating with the inlet port  502  and a second flow path  501   b  that connects the first flow path  501   a  and the outlet port  503  and extends in a circumferential direction thereof. However, such a structure of the sub-flow path  501  is given as only an example, the sub-flow path  501  is sufficient only to connect the inlet port  502  and the outlet port  503 , and the structure, shape, and arrangement thereof are not limited. 
     The inlet port  502  may be provided on the main flow path P between the blower fan  40  and the heat exchanger  30 . Accordingly, some of the air blown by the blower fan  40  may be introduced into the sub-flow path  501  through the inlet port  502 . 
     The outlet port  503  may be provided to be directed approximately downward from the radially inner side of the discharge port  21 . The outlet port  503  may be provided to have a sectional area smaller than that of the discharge port  21 . Further, a radially inner surface of the outlet port  503  may include a Coanda curved surface portion  503   a  that guides the air discharged through the outlet port  503  in an approximately downward direction. The first guide surface  14   a  and the Coanda curved surface portion  503   a  may be formed to have a step. 
     According to such a configuration, the outlet port  503  may convert the flow direction of the air discharged through the discharge port  21 . Specifically, the flow direction of the air discharged through the outlet port  503  is further directed to the radially inner side of the discharge port  21  than that of the air discharged through the discharge port  21 . 
     With such a configuration, the air discharged through the outlet port  503  is discharged at a high speed and induces the air discharged from the discharge port  21  to draw the air toward the outlet port  503 . In other words, the discharge direction of the air discharged from the discharge port  21  is converted from the direction A 1  to the direction A 2 . 
     An opening/closing control device  504  configured to adjust an opening degree of the sub-flow path  501  may be provided on the sub-flow path  501  adjacent to the inlet port  502 . The discharge direction of the air discharged from the discharge port  21  may be converted between the direction A 1  and the direction A 2  by selectively opening the sub-flow path  501  through the opening/closing control device  504 . 
     In addition, as in the above-described exemplary embodiments, the opening/closing control device  504  may adjust an amount of the air, which is discharged through the outlet port  503  after passing through the sub-flow path  501 , by adjusting the opening degree of the sub-flow path  501 . Further, the degree of flow direction conversion of the air discharged through the discharge port  21  may be adjusted accordingly. 
       FIG. 10  illustrates a cross-sectional view of an air conditioner  6  according to yet another exemplary embodiment of the present invention. The air conditioner  6  according to yet another exemplary embodiment of the present invention will be described with reference to  FIG. 10 . However, the same reference symbols will be assigned to the same components as those in the exemplary embodiments described above, and the description thereof will be omitted. 
     The air conditioner  6  may control the discharged airflow by bypassing some of the air blown by the blower fan  40  to a sub-flow path  601  and then discharging the air in a direction different from that of the air discharged through the discharge port  21 . On the other hand, the sub-flow path  601  may control the discharged airflow by discharging air in a direction similar to that of the air discharged through the discharge port  21 . In this case, the sub-flow path  601  may be provided such that the air blown by the blower fan  40  is branched off from the main flow path P after passing through the heat exchanger  30 . 
     The sub-flow path  601  may connect an inlet port  602  and an outlet port  603 . The sub-flow path  601  may be formed along the outer wall of the housing  10  using a separate duct, or formed inside the housing  10 . 
     The sub-flow path  601  may include a first flow path  601   a  communicating with the inlet port  602  and a second flow path  601   b  that connects the first flow path  601   a  and the outlet port  603  and extends in a circumferential direction thereof. However, such a structure of the sub-flow path  601  is given as only an example, the sub-flow path  601  is sufficient only to connect the inlet port  602  and the outlet port  603 , and the structure, shape, and arrangement thereof are not limited. 
     The inlet port  602  may be provided on the main flow path P between the heat exchanger  30  and the discharge port  21 . Accordingly, some of the air that is blown by the blower fan  40  and then passes through the heat exchanger  30  may be introduced into the sub-flow path  601  through the inlet port  602 . 
     The outlet port  603  may be provided toward the radially outer side of the discharge port  21 . The outlet port  603  may have a sectional area smaller than that of the discharge port  21 . The second guide surface  14   b  in which the outlet port  603  is formed may be formed to have a step with respect to the outlet port  603 . The second guide surface  14   b  may include a Coanda curved surface portion  603   a  that guides the air discharged through the outlet port  603  toward the radially outer side of the discharge port  21 . The Coanda curved surface portion  603   a  may be provided to be approximately parallel with the second guide surface  14   b , and provided to have a different slope and curvature. 
     According to such a configuration, the outlet port  603  may convert the flow direction of the air discharged through the discharge port  21 . Specifically, the flow direction of the air discharged through the outlet port  603  is further directed to the radially outer side of the discharge port  21  than that of the air discharged through the discharge port  21 . 
     Accordingly, the air discharged through the outlet port  603  is discharged at a high speed and induces the air discharged from the discharge port  21  to draw the air toward the outlet port  603 . In other words, the discharge direction of the air discharged from the discharge port  21  is converted from the direction A 1  to the direction A 2 . 
     An opening/closing control device  604  configured to adjust an opening degree of the sub-flow path  601  may be provided on the sub-flow path  601  adjacent to the inlet port  602 . The discharge direction of the air discharged from the discharge port  21  may be converted between the direction A 1  and the direction A 2  by selectively opening the sub-flow path  601  through the opening/closing control device  604 . 
     In addition, as in the above-described exemplary embodiments, the opening/closing control device  604  may adjust an amount of the air, which is discharged through the outlet port  603  after passing through the sub-flow path  601 , by adjusting the opening degree of the sub-flow path  601 . Accordingly, the degree of flow direction conversion of the air discharged through the discharge port  21  may be adjusted. 
       FIG. 11  illustrates a cross-sectional view of an air conditioner  7  according to yet another exemplary embodiment of the present invention.  FIG. 11  illustrates an expanded view of portion O′ shown in  FIG. 3 . The air conditioner  7  according to yet another exemplary embodiment of the present invention will be described with reference to  FIG. 11 . However, the same reference symbols will be assigned to the same components as those in the exemplary embodiments described above, and the description thereof will be omitted. 
     The air conditioner  7  may control the discharged airflow by bypassing some of the air blown by the blower fan  40  to a sub-flow path  701  and then discharging the air in a direction different from that of the air discharged through the discharge port  21 . Conversely, the sub-flow path  701  may control the discharged airflow by discharging the air in a direction similar to that of the air discharged through the discharge port  21 . For the purpose, the air conditioner  7  includes the sub-flow path  701  branched off from the main flow path P. The sub-flow path  701  may be provided such that the air blown by the blower fan  40  is branched off from the main flow path P before passing through the heat exchanger  30 . 
     The sub-flow path  701  may connect an inlet port  702  through which some of the air flowing through the main flow path P is introduced and an outlet port  703  through which the air introduced through the inlet port  702  is discharged. The sub-flow path  701  may be provided to pass from the radially inner side of the discharge port  21  through the inside of the bridge  80  to the radially outer side of the discharge port  21 . The sub-flow path  701  may include a first flow path  701   a  communicating with the inlet port  702  and a second flow path  701   b  that connects the first flow path  701   a  and the outlet port  703  and extends in a circumferential direction thereof. That is, the air introduced through the inlet port  702  passes through the first flow path  701   a  and the inside of the bridge  80 , then passes through the second flow path  701   b , and is discharged to the outlet port  703 . However, such a structure of the sub-flow path  701  is given as only an example, the sub-flow path  701  is sufficient only to connect the inlet port  702  and the outlet port  703 , and the structure, shape, and arrangement thereof are not limited. 
     As shown in  FIG. 9 , the inlet port  702  may be provided on the main flow path P between the blower fan  40  and the heat exchanger  30 . Accordingly, some of the air that is blown by the blower fan  40  may be introduced into the sub-flow path  701  through the inlet port  702 . 
     As shown in  FIG. 10 , the outlet port  703  may be provided toward the radially outer side of the discharge port  21 . The outlet port  703  may have a sectional area smaller than that of the discharge port  21 . The second guide surface  14   b  in which the outlet port  703  is formed may be formed to have a step with respect to the outlet port  703 . Further, the second guide surface  14   b  may include a Coanda curved surface portion  703   a  that guides the air discharged through the outlet port  703  toward the radially outer side of the discharge port  21 . 
     With such a configuration, the outlet port  703  may convert the flow direction of the air discharged through the discharge port  21 . Specifically, the flow direction of the air discharged through the outlet port  703  is further directed to the radially outer side of the discharge port  21  than that of the air discharged through the discharge port  21 . 
     Accordingly, the air discharged through the outlet port  703  is discharged at a high speed and induces the air discharged from the discharge port  21  to draw the air toward the outlet port  703 . In other words, the discharge direction of the air discharged from the discharge port  21  is converted from the direction A 1  to the direction A 2 . 
     An opening/closing control device  704  configured to adjust an opening degree of the sub-flow path  701  may be provided on the sub-flow path  701  adjacent to the inlet port  702 . The discharge direction of the air discharged from the discharge port  21  may be converted between the direction A 1  and the direction A 2  by selectively opening the sub-flow path  701  through the opening/closing control device  704 . 
     In addition, as in the above-described exemplary embodiments, the opening/closing control device  704  may adjust an amount of the air, which is discharged through the outlet port  703  after passing through the sub-flow path  701 , by adjusting the opening degree of the sub-flow path  701 . Accordingly, the degree of flow direction conversion of the air discharged through the discharge port  21  may be adjusted. 
     The foregoing has been shown and described with reference to specific exemplary embodiments. However, the present invention is not limited thereto, and various changes and modifications may be made by a person of ordinary skill in the art to which the present invention pertains without departing from the scope of the present invention defined in the following claims.