Patent Publication Number: US-10330357-B2

Title: Air conditioner and cooling receiver of air conditioner

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The application claims priority under 35 U.S.C. § 119 and 35 U.S.C. § 365 to Korean Patent Application No. 10-2015-0129284, filed Sep. 11, 2015, whose entire disclosure is hereby incorporated by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     An air conditioner and a cooling receiver of the air conditioner and, more particularly, an air conditioner that supercools and stores a liquid refrigerant and a cooling receiver of the air conditioner. 
     2. Description of the Related Art 
     An air conditioner is an apparatus for cooling or heating the interior of a room using an air-conditioning cycle including a compressor, an outside (also referred to as outdoor) heat exchanger, an expansion device, and an inside (also referred to as indoor) heat exchanger. The air conditioner may include a cooling unit for cooling the interior of a room and a heating unit for heating the interior of a room. Furthermore, the air conditioner may be a combined cooling and heating air conditioner for cooling or heating the interior of a room. 
     The combined cooling and heating air conditioner generally includes a cooling/heating switching valve for changing the flow channel of a refrigerant compressed by a compressor depending on a cooling operation and a heating operation. When a cooling operation is performed, the refrigerant compressed by the compressor flows into the outside heat exchanger through the cooling/heating switching valve. The outside heat exchanger functions as a condenser. The refrigerant condensed by the outside heat exchanger is expanded by the expansion device and then flows into the inside heat exchanger. In this case, the inside heat exchanger functions as an evaporator. The refrigerant evaporated by the inside heat exchanger flows into the compressor again through the cooling/heating switching valve. 
     When a heating operation is performed, the refrigerant compressed by the compressor flows into the inside heat exchanger through the cooling/heating switching valve. The inside heat exchanger functions as a condenser. The refrigerant condensed by the inside heat exchanger is expanded by the expansion device and then flows into the outside heat exchanger. As such, the outside heat exchanger functions as an evaporator. The refrigerant evaporated by the outside heat exchanger flows into the compressor again through the cooling/heating switching valve. 
     The combined cooling and heating air conditioner may include a plurality of inside units each having an inside heat exchanger may. Only some of the plurality of inside units may operate as a partial load. If only some of connected inside units operate, a refrigerant of a low-pressure gas state is present within the inside heat exchanger of the stopped inside unit. If the refrigerant is sealed by taking into consideration the number of connected inside units, then the refrigerant of an inside unit that does not operate transfers to the outside heat exchanger, which changes a refrigerant circulation state. Accordingly, the optimal amount of a refrigerant may not be distributed to the air-conditioning cycle. 
     Furthermore, when the heating operation is performed, the functions of the outside heat exchanger and inside heat exchanger of the air conditioner are changed. A ratio of the volumes of the outside heat exchanger and inside heat exchanger is changed depending on the number of connected inside units. Furthermore, it is necessary to control the amount of a refrigerant in response to a change in cooling/heating operation mode. 
     Accordingly, a receiver in which a refrigerant is stored is installed on the air-conditioning cycle to optimize the amount of the refrigerant of the air-conditioning cycle. The receiver functions to transfer a refrigerant stored therein to the air-conditioning cycle when the amount of the refrigerant of the air-conditioning cycle is insufficient and functions to store the refrigerant of the air-conditioning cycle when the amount of the refrigerant of the air-conditioning cycle is excessive, so the amount of the refrigerant of the air-conditioning cycle becomes an optimal amount. Also, the air conditioner may include a supercooler to supercool a refrigerant that has passed through the outside heat exchanger when the cooling operation is performed. The supercooler, disposed between the outside heat exchanger and the inside heat exchanger, functions as an intercooler. 
     Recently, complex type air conditioners are being installed in locations, such as supermarkets. More particularly, the complex type air conditioner integrates an air-conditioning cycle circuit for air-conditioning the interior of a room and a refrigeration cycle circuit for refrigerating a low-temperature storage unit (such as a display case for storing food at a low temperature). In the complex type air conditioner, the supercooler supercools a refrigerant that has passed through the condenser of the refrigeration cycle circuit and overheats a refrigerant that has passed through the condenser of the air-conditioning cycle circuit. This is done by thermally exchanging the refrigerant passing through the condenser of the refrigeration cycle circuit and the refrigerant passing through the condenser of the air-conditioning cycle circuit. However, such conventional air conditioners are problematic because installation space is limited. Moreover, because the receiver and the supercooler are separately formed, the structure is complicated and costly due to the configuration of refrigerant pipes for forming the receiver and the supercooler into a cycle circuit, and refrigeration efficiency is low. 
     SUMMARY OF THE INVENTION 
     An object of the present disclosure is to provide an air conditioner in which a supercooler and a receiver are integrated, and a cooling receiver of the air conditioner. 
     Object of the present disclosure are not limited to the aforementioned object, and those skilled in the art may evidently understand other objects not described above from the following description. 
     An air conditioner according to an embodiment of the present disclosure includes an air-conditioning cycle circuit configured to have a refrigerant to circulate through a first compressor, a first condenser, a first expansion device, and a first evaporator, a refrigeration cycle circuit configured to have a refrigerant to circulate through a second compressor, a second condenser, a second expansion device, and a second evaporator, and a cooling receiver configured to thermally exchange a refrigerant passed through the second condenser and a refrigerant passed through the first condenser and to store the thermally exchanged refrigerant. The cooling receiver includes a cooling unit configured to include at least one first refrigerant flow channel through which the refrigerant passed through the second condenser flows and a second refrigerant flow channel which surrounds the outer circumference of part of the at least one first refrigerant flow channel and through which the refrigerant passed through the first condenser flows and supercools the refrigerant flowing through the first refrigerant flow channel, and a receiver unit configured to have at least one end of the cooling unit disposed in the receiver unit and to store the supercooled refrigerant exiting from the first refrigerant flow channel. 
     Furthermore, a cooling receiver of an air conditioner according to an embodiment of the present disclosure includes a cooling unit configured to include at least one first refrigerant flow channel through which a refrigerant flows and a second refrigerant flow channel which surrounds the outer circumference of part of the at least one first refrigerant flow channel and through which a refrigerant flows and supercools a refrigerant flowing through the first refrigerant flow channel and a receiver unit configured to have at least one end of the cooling unit disposed in the receiver unit and to store the supercooled refrigerant exiting from the first refrigerant flow channel. 
     Details of other embodiments are included in the detailed description and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention. In the drawings: 
         FIG. 1  is a configuration diagram showing an air conditioner according to an embodiment of the present disclosure. 
         FIG. 2  is a detailed view of a cooling receiver shown in  FIG. 1 . 
         FIG. 3  is a cross-sectional view of the cooling receiver taken along line A-A of  FIG. 2 . 
         FIG. 4  is a diagram showing a flow of a refrigerant when the cooling operation and refrigeration operation of the air conditioner are performed at the same time according to an embodiment of the present disclosure. 
         FIG. 5  is a diagram showing a flow of a refrigerant when the heating operation and refrigeration operation of the air conditioner are performed at the same time according to an embodiment of the present disclosure. 
         FIG. 6  is a diagram showing a flow of a refrigerant when only the refrigeration operation of the air conditioner is performed according to an embodiment of the present disclosure. 
         FIG. 7  is a plan sectional view showing another embodiment of the cooling receiver. 
         FIG. 8  is a perspective view showing the lower part of the cooling receiver shown in  FIG. 7 . 
         FIG. 9  is a perspective view showing the upper part of the cooling receiver shown in  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Advantages and features of the present disclosure and methods for achieving the merits and characteristics will be more clearly understood from embodiments described in detail later in conjunction with the accompanying drawings. However, the present disclosure is not limited to the disclosed embodiments, but may be implemented in various different ways. The embodiments are provided to only complete the disclosure of the present disclosure and to allow a person having ordinary skill in the art to which the present disclosure pertains to completely understand the category of the invention. The present disclosure is only defined by the category of the claims. The same reference numbers are used to refer to the same or similar elements throughout the specification. 
     Hereinafter, an air conditioner and a cooling receiver of the air conditioner according to embodiments of the present disclosure are described in detail with reference to the accompanying drawings. 
       FIG. 1  is a configuration diagram showing an air conditioner according to an embodiment of the present disclosure. Referring to  FIG. 1 , the air conditioner includes an air-conditioning cycle circuit  1  and a refrigeration cycle circuit  2 . The air-conditioning cycle circuit  1  may include an air-conditioning outside unit O 1  (also referred to as outdoor unit O 1 ) that is installed outsides and an air-conditioning inside unit I 1  (also referred to as an air-conditioning indoor unit I 1 ) that is installed inside. The refrigeration cycle circuit  2  may include a refrigeration outside unit O 2  that is installed outside and a refrigeration inside unit I 2  (also referred to as a refrigeration inside unit I 2 ) that is installed indoors. The air-conditioning cycle circuit  1  may air-condition (or cool/heat) the interior of a room. The refrigeration cycle circuit  2  may refrigerate (or cool/freeze) food stored in the refrigeration inside unit I 2 . 
     First, the air-conditioning cycle circuit  1  is described below. 
     The air-conditioning cycle circuit  1  may include a first compressor  11 , an outside heat exchanger  13  (also referred to as outdoor heat exchanger  13 ), a first expansion device  14 ,  15 , and an inside heat exchanger  16  (also referred to as an indoor heat exchanger  16 ). 
     In the air-conditioning cycle circuit  1 , when a cooling operation is performed, a refrigerant may circulate in order of the first compressor  11 , the outside heat exchanger  13 , the first expansion device  14 ,  15 , the inside heat exchanger  16 , and the first compressor  11 . In the air-conditioning cycle circuit  1 , when the cooling operation is performed, the outside heat exchanger  13  may function as a first condenser, and the inside heat exchanger  16  may function as a first evaporator. 
     Furthermore, in the air-conditioning cycle circuit  1 , when a heating operation is performed, a refrigerant may circulate in order of the first compressor  11 , the inside heat exchanger  16 , the first expansion device  14 ,  15 , the outside heat exchanger  13 , and the first compressor  11 . In the air-conditioning cycle circuit  1 , when the heating operation is performed, the outside heat exchanger  13  may function as a first evaporator, and the inside heat exchanger  16  may function as a first condenser. 
     The air-conditioning cycle circuit  1  may further include a cooling/heating switching valve  12  configured to enable a refrigerant to circulate through the first compressor  11 , the outside heat exchanger  13 , the first expansion device  14 ,  15 , and the inside heat exchanger  16  when a cooling operation is performed, and configured to enable a refrigerant to circulate through the first compressor  11 , the inside heat exchanger  16 , the first expansion device  14 ,  15 , and the outside heat exchanger  13  when a heating operation is performed. 
     The first compressor  11  may suction (e.g., suck) a refrigerant, may compress the refrigerant, and may then discharge the compressed refrigerant. A plurality of the first compressors  11  may be connected in parallel or in series. A suction flow channel  11   a  through which a refrigerant is suctioned into the first compressor  11  may be connected to the first compressor  11 . A discharge flow channel  11   b  through which a compressed refrigerant is discharged from the first compressor  11  may be connected to the first compressor  11 . If a plurality of the first compressors  11  are connected in parallel, the suction flow channel  11   a  may likewise be connected in parallel to the plurality of first compressors  11 , and the discharge flow channel  11   b  may likewise be connected in parallel to the plurality of first compressors  11 . 
     The outside heat exchanger  13  may operate as the first condenser in which a refrigerant compressed by the first compressor  11  is condensed when a cooling operation is performed. The outside heat exchanger  13  may operate as the first evaporator in which a refrigerant expanded by the first expansion device  14 ,  15  is evaporated when a heating operation is performed. The outside heat exchanger  13  may include an air-refrigerant heat exchanger configured to thermally exchange an outside air and a refrigerant. The outside heat exchanger  13  may include a water-cooling heat exchanger configured to thermally exchange heat source water, such as water or an antifreezing solution, and a refrigerant. 
     The first expansion device  14 ,  15  includes an outside expansion valve  14  (also referred to as an outdoor expansion valve  14 ) and an inside expansion valve  15  (also referred to as an indoor expansion valve  15 ). The outside expansion valve  14  may be installed between the inside expansion valve  15  and the outside heat exchanger  13 , and may be installed closer to the outside heat exchanger  13  than to the inside heat exchanger  16 . The outside expansion valve  14  may not expand a refrigerant when a cooling operation is performed, but may expand a refrigerant when a heating operation is performed. The outside expansion valve  14  may be fully open upon cooling, and may be controlled to a set opening degree upon heating. The outside expansion valve  14  may be installed on a bypass pipe installed on a refrigerant pipe between the outside heat exchanger  13  and the inside expansion valve  15 . 
     A check valve configured to enable a refrigerant to flow into the inside expansion valve  15  when a cooling operation is performed and to enable a refrigerant to flow into the outside expansion valve  14  by blocking the refrigerant when a heating operation is performed may be installed on the refrigerant pipe between the outside heat exchanger  13  and the inside expansion valve  15 . The inside expansion valve  15  may be installed between the outside heat exchanger  13  and the inside heat exchanger  16 , and may be installed proximately closer to the inside heat exchanger  16  than to the outside heat exchanger  13 . 
     The inside heat exchanger  16  may function as the first evaporator in which a refrigerant expanded by the first expansion device  14 ,  15  is evaporated when a cooling operation is performed. The inside heat exchanger  16  may function as a first condenser in which a refrigerant compressed by the first compressor  11  is condensed when a heating operation is performed. 
     The cooling/heating switching valve  12  may be a 4-way valve. For example, the cooling/heating switching valve  12  may be connected to the first compressor  11  through the suction flow channel  11   a  of the first compressor  11 , may be connected to the first compressor  11  through the discharge flow channel  11   b  of the first compressor  11 , may be connected to the outside heat exchanger  13  through the suction/discharge flow channel  13   a  of the outside heat exchanger  13 , and may be connected to the inside heat exchanger  16  through an air conditioner pipe  17 . 
     Furthermore, the outside heat exchanger  13  and the inside heat exchanger  16  may be connected through an air-conditioning liquid line  18 . 
     An air conditioner pipe valve  17   a  configured to open/shut the air conditioner pipe  17  may be installed on the air conditioner pipe  17 . An air-conditioning liquid line valve  18   a  configured to open/shut air-conditioning liquid line  18  may be installed on the air-conditioning liquid line  18 . 
     The air-conditioning cycle circuit  1  may further include a first accumulator (not shown) installed between the cooling/heating switching valve  12  and the first compressor  11 . The first accumulator may be installed on the suction flow channel  11   a  of the first compressor  11 . Accordingly, a refrigerant that flows from the cooling/heating switching valve  12  to the first compressor  11  may flow into the first accumulator. A liquid refrigerant of the refrigerant that has flowed into the first accumulator may be accumulated in the first accumulator, and a gaseous refrigerant of the refrigerant that has flowed into the first accumulator may be suctioned into the first compressor  11 . 
     The refrigeration cycle circuit  2  is described below. 
     The refrigeration cycle circuit  2  may include a second compressor  21 , a second condenser  23 , a second expansion device  25 , and a second evaporator  26 . 
     In the refrigeration cycle circuit  2 , a refrigerant may circulate in order of the second compressor  21 , the second condenser  23 , the second expansion device  25 , the second evaporator  26 , and the second compressor  21 . 
     The second compressor  21  may compress the suctioned refrigerant, and may discharge the compressed refrigerant. A plurality of the second compressors  21  may be connected in parallel or in series. A suction flow channel  21   a  through which a refrigerant is suctioned into the second compressor  21  may be connected to the second compressor  21 . A discharge flow channel  21   b  through which a refrigerant compressed by the second compressor  21  is discharged may be connected to the second compressor  21 . If a plurality of the second compressors  21  are connected in parallel, the suction flow channel  21   a  may likewise be connected in parallel to the plurality of second compressors  21 , and the discharge flow channel  21   b  may likewise be connected in parallel to the plurality of second compressors  21 . 
     The second condenser  23  condenses a refrigerant compressed by the second compressor  21 . The second condenser  23  may include an air-refrigerant heat exchanger configured to thermally exchange an outside air and a refrigerant. The second condenser  23  may include a water-cooling heat exchanger configured to thermally exchange heat source water, such as water or an antifreezing solution, and a refrigerant. 
     The second expansion device  25  expands a refrigerant that enters into the second evaporator  26 . The second expansion device  25  may be installed between the second condenser  23  and the second evaporator  26 , and may be installed proximately closer to the second evaporator  26  than to the second condenser  23 . 
     The second evaporator  26  may evaporate a refrigerant (for example, while refrigerating food stored in the refrigeration inside unit I 2 ) by thermally exchanging the refrigerant expanded by the second expansion device  25  and an air within the refrigeration inside unit I 2 . 
     The second compressor  21  may be connected to the second evaporator  26  through the suction flow channel  21   a . The second compressor  21  may be connected to the second condenser  23  through the discharge flow channel  21   b . The second condenser  23  and the second evaporator  26  may be connected through the suction flow channel  26   a  of the second evaporator  26 . 
     A first suction flow channel valve  21   c  configured to open/shut the suction flow channel  21   a  may be installed on the suction flow channel  21   a  of the second compressor  21 . A second suction flow channel valve  26   b  configured to open/shut a suction flow channel  26   a  may be installed on the suction flow channel  26   a  of the second evaporator  26 . 
     The refrigeration cycle circuit  2  may further include a second accumulator (not shown) installed between the second evaporator  26  and the second compressor  21 . The second accumulator may be installed on the suction flow channel  21   a  of the second compressor  21 . Accordingly, a refrigerant flowing from the second evaporator  26  to the second compressor  21  may flow into the second accumulator, a liquid refrigerant of the refrigerant that has flowed into the second accumulator may be accumulated in the second accumulator, and a gaseous refrigerant of the refrigerant that has flowed into the second accumulator may be suctioned into the second compressor  21 . 
     The air conditioner according to an embodiment of the present disclosure may further include a cooling receiver  50  configured to thermally exchange a refrigerant that has passed through the second condenser  23  and a refrigerant that has passed through one of the outside heat exchanger  13  and the inside heat exchanger  16 , which functions as the first condenser. 
     The cooling receiver  50  is described in detail below. 
       FIG. 2  is a detailed view of the cooling receiver shown in  FIG. 1 .  FIG. 3  is a cross-sectional view of the cooling receiver taken along line A-A of  FIG. 2 . 
     Referring to  FIGS. 1, 2, and 3 , the cooling receiver  50  includes a cooling unit  51  and a receiver unit  54  in which at least one end of the cooling unit  51  is disposed. 
     The cooling unit  51  includes at least one first refrigerant flow channel  52  through which a refrigerant that has passed through the second condenser  23  flows and a second refrigerant flow channel  53  configured to surround the outer circumference of some of the at least one first refrigerant flow channel  52 . A refrigerant that has passed through one of the outside heat exchanger  13  and the inside heat exchanger  16 , which functions as the first condenser, is thermally exchanged with a refrigerant flowing through the first refrigerant flow channel  52  while flowing through the inside of the second refrigerant flow channel  53 . Accordingly, the refrigerant flowing through the first refrigerant flow channel  52  is supercooled, and the refrigerant flowing through the second refrigerant flow channel  53  is gasified. 
     At least one end of the cooling unit  51  is disposed in the receiver unit  54 , and a supercooled refrigerant exiting from the first refrigerant flow channel  52  is stored in the receiver unit  54 . 
     As shown, the cooling unit  51  and the receiver unit  54  may be formed to have a cylindrical shape. The diameters of the first refrigerant flow channel  52 , the second refrigerant flow channel  54 , and the receiver unit may be sized relative to each other. For example, the diameter of the first refrigerant flow channel  52  may be the smallest, the diameter of the second refrigerant flow channel  53  may be larger than that of the first refrigerant flow channel  52 , and the diameter of the receiver unit  54  may be larger than that of the second refrigerant flow channel  53 . The first refrigerant flow channel  52 , as shown, may be formed of seven thin-necked pipes. 
     The cooling unit  51  may have an upper end inserted and disposed in the receiver unit  54  and a lower end protruded to the lower side of the receiver unit  54 , such that the lower end may be exposed to the outside of the receiver unit  54 . 
     In the cooling unit  51 , the first refrigerant flow channel  52  having the upper end disposed within the receiver unit  54  is open, and the second refrigerant flow channel  53  is shut. The open upper end of the first refrigerant flow channel  52  may be protruded upward from the upper end of the second refrigerant flow channel  53 . Accordingly, a refrigerant flowing through the first refrigerant flow channel  52  may be supercooled through a thermal exchange with a refrigerant flowing through the second refrigerant flow channel  53 . Next, the supercooled refrigerant may exit from the open upper end of the first refrigerant flow channel  52  and may be stored in the internal space of the receiver unit  54 . 
     A first inlet flow channel  52   a  and a second inlet flow channel  53   a  may be disposed at a portion that belongs to the cooling unit  51  and that is protruded toward the lower side of the receiver unit  54 . A first outlet flow channel  53   b  may be disposed at the upper side of the receiver unit  54 , and a second outlet flow channel  54   a  may be disposed at the lower side of the receiver unit  54 . 
     The first inlet flow channel  52   a  may be connected to the first refrigerant flow channel  52  through the second refrigerant flow channel  53 . The first inlet flow channel  52   a  thus supplies the first refrigerant flow channel  52  with a refrigerant that has passed through the second condenser  23 . In configurations in which the second refrigerant flow channel  53  includes a plurality of the first refrigerant flow channels  52 , the first inlet flow channel  52   a  may branch into a plurality of the first inlet flow channels within the second refrigerant flow channel  53  and then connect with the plurality of first refrigerant flow channels  52 . 
     The second inlet flow channel  53   a  may be connected to the second refrigerant flow channel  53 . The second inlet flow channel  53   a  thus supplies the second refrigerant flow channel  53  with a refrigerant that has passed through one of the outside heat exchanger  13  and the inside heat exchanger  16 , which functions as the first condenser. The second refrigerant flow channel  53  may be connected to the air-conditioning liquid line  18  through a heat recovery liquid line  34  branched from the air-conditioning liquid line  18  that connects the second outside heat exchanger  13  and the inside heat exchanger  16 . That is, the heat recovery liquid line  34  connects the second refrigerant flow channel  53  and the air-conditioning liquid line  18 . 
     A heat recovery expansion device  34   a  may be installed on the heat recovery liquid line  34 . Accordingly, some of a refrigerant that has passed through the first condenser may flow to the first evaporator through the air-conditioning liquid line  18 . The remainder of the refrigerant may flow to the heat recovery liquid line  34 , may be expanded by the heat recovery expansion device  34   a , and may then flow to the second inlet flow channel  53   a . The refrigerant that has flowed to the second inlet flow channel  53   a  may be supplied to the second refrigerant flow channel  53 . 
     The first outlet flow channel  53   b  may be connected to the upper part of the second refrigerant flow channel  53  within the receiver unit  54  through the upper end of the receiver unit  54 . Accordingly, a refrigerant supplied to the second refrigerant flow channel  53  through the second inlet flow channel  53   a  may pass through the second refrigerant flow channel  53  and then exit through the first outlet flow channel  53   b . The first outlet flow channel  53   b  protruded to the upper end of the receiver unit  54  may be connected to the suction flow channel  11   a  of the first compressor  11  through the heat recovery line  35 . Accordingly, the refrigerant that has exited through the first outlet flow channel  53   b  may flow to the suction flow channel  11   a  of the first compressor  11  through the heat recovery line  35 , and may be supplied to the first compressor  11 . 
     The second outlet flow channel  54   a  may be connected to the suction flow channel  26   a  of the second evaporator  26 . Accordingly, a supercooled refrigerant that has exited through the upper end of the first refrigerant flow channel  52  and has stored in the receiver unit  54  may exit through the second outlet flow channel  54   a , may flow to the suction flow channel  26   a  of the second evaporator  26 , and may be then supplied to the second evaporator  26 . 
     A cap  54   b  configured to cover the upper end of the receiver unit  54  may be disposed at the upper end of the receiver unit  54 . If the cap  54   b  is so disposed, the first outlet flow channel  53   b  may penetrate the cap  54   b.    
     At least one mounting bracket  55  may be disposed at the lower part of the receiver unit  54 . For example, the mounting bracket  55  may include a ring-shaped main body unit  55   a  configured to surround the outer circumferential surface of the receiver unit  54  and a plurality of mounting units  55   b  disposed on the outer circumferential surface of the main body unit  55   a  and spaced apart from each other at an equal distance or interval. The three mounting units  55   b  may be included in the mounting bracket  55 . The mounting unit  55   b  may be mounted on the refrigeration outside unit O 2 , thus coupling the receiver unit  54  to the refrigeration outside unit O 2 . 
     A heat recovery liquid line valve  34   b  configured to open/shut the heat recovery liquid line  34  may be installed in the heat recovery liquid line  34 . Heat recovery line valves  35   a  and  35   b  configured to open/shut the heat recovery line  35  may be installed on the heat recovery line  35 . The heat recovery line valves  35   a  and  35   b  include a first heat recovery line valve  35   a  disposed in the refrigeration outside unit O 2  and a second heat recovery line valve  35   b  disposed in the air-conditioning outside unit O 1 . 
     The air conditioner pipe valve  17   a , the air-conditioning liquid line valve  18   a , the first suction flow channel valve  21   c , the second suction flow channel valve  26   b , the heat recovery liquid line valve  34   b , and the heat recovery line valves  35   a  and  35   b  may be open at normal times and may be shut by a user when a service (e.g., the filling of a refrigerant or a failure) is performed on the air conditioner. 
     The first compressor  11 , the four-way valve  12 , the outside heat exchanger  13 , the outside expansion valve  14 , the air conditioner pipe valve  17   a , the air-conditioning liquid line valve  18   a , and the second heat recovery line valve  35   b  may be included in the air-conditioning outside unit O 1 . 
     The second compressor  21 , the second condenser  23 , the cooling receiver  50 , the first suction flow channel valve  21   c , the second suction flow channel valve  26   b , the heat recovery liquid line valve  34   b , and the first heat recovery line valve  35   a  may be included in the refrigeration outside unit O 2 . 
     The inside heat exchanger  16  and the inside expansion valve  15  may be included in the air-conditioning inside unit I 1 . Furthermore, the second evaporator  26  and the second expansion device  25  may be included in the refrigeration inside unit I 2 . 
     Operations of the air conditioner configured as described above according to embodiments of the present disclosure are described below. 
       FIG. 4  is a diagram showing a flow of a refrigerant when the cooling operation and refrigeration operation of the air conditioner are performed at the same time according to an embodiment of the present disclosure. 
     Referring to  FIG. 4 , the air conditioner may simultaneously perform a cooling operation for cooling the interior of a room and a refrigeration operation for refrigerating food within the refrigeration inside unit I 2 . That is, for example, when the cooling operation of the air-conditioning cycle circuit  1  is performed, the first compressor  11  is driven and the air-conditioning cycle circuit  1  discharges a refrigerant. 
     The refrigerant discharged by the first compressor  11  flows to the cooling/heating switching valve  12  through the discharge flow channel  11   b  of the first compressor  11 . The refrigerant that has flowed to the cooling/heating switching valve  12  flows to the outside heat exchanger  13  through the suction/discharge flow channel  13   a  of the outside heat exchanger  13 . When the cooling operation of the air-conditioning cycle circuit  1  is performed, the outside heat exchanger  13  functions as the first condenser. 
     Some of the refrigerant that has passed through the outside heat exchanger  13  moves to the inside heat exchanger  16  through the air-conditioning liquid line  18 . The remainder of the refrigerant that has passed through the outside heat exchanger  13  flows to the cooling receiver  50  through the heat recovery liquid line  34 . 
     Some of the refrigerant that passes through the outside heat exchanger  13  and that flows to the inside heat exchanger  16  through the air-conditioning liquid line  18  is supplied to the inside heat exchanger  16  when the refrigerant has been expanded by the first expansion device  15 . When the cooling operation of the air-conditioning cycle circuit  1  is performed, the inside heat exchanger  16  functions as the first evaporator. The refrigerant that has flowed to the inside heat exchanger  16  may refrigerate air within a room and may be evaporated, while it is thermally exchanged with the air within the room. The refrigerant evaporated by the inside heat exchanger  16  may flow to the cooling/heating switching valve  12  through the air conditioner pipe  17 , and may be then supplied to the first compressor  11  again through the suction flow channel  11   a  of the first compressor  11 . 
     The refrigeration cycle circuit  2  may drive the second compressor  21  and discharge a refrigerant. The refrigerant discharged by the second compressor  21  may flow to the second condenser  23  through the discharge flow channel  21   b  of the second compressor  21 . The refrigerant that has flowed to the second condenser  23  may flow to the second evaporator  26  through the suction flow channel  26   a  of the second evaporator  26 . 
     The refrigerant that has passed through the second condenser  23  may be supplied to the second evaporator  26  when the refrigerant has been expanded by the second expansion device  25 . The refrigerant that has flowed to the second evaporator  26  may refrigerate food within the refrigeration inside unit I 2  and may be evaporated, while it is thermally exchanged with air within the refrigeration inside unit I 2 . The refrigerant evaporated by the second evaporator  26  may be supplied to the second compressor  21  again through the suction flow channel  21   a  of the second compressor  21 . 
     The remaining of the refrigerant that passes through the outside heat exchanger  13  of the air-conditioning cycle circuit  1  and has flowed to the cooling receiver  50  through the heat recovery liquid line  34  may be expanded by the heat recovery expansion device  34   a , may flow to the second refrigerant flow channel  53 , and may be gasified through a thermal exchange with the refrigerant that has passed through the second condenser  23  of the refrigeration cycle circuit  2  within the cooling receiver  50  while supercooling the refrigerant that has passed through the second condenser  23 . 
     The cooling receiver  50  may be installed between the second condenser  23  and the second expansion device  25  on the suction flow channel  26   a  of the second evaporator  26 . The refrigerant that has passed through the second condenser  23  may be thermally exchanged with the refrigerant flowing through the second refrigerant flow channel  53  and supercooled, while it flows through the first refrigerant flow channel  52 . 
     The refrigerant supercooled while flowing through the first refrigerant flow channel  52  may exit through the open upper end of the first refrigerant flow channel  52 , and may be then stored in the receiver unit  54 . The refrigerant gasified while flowing through the second refrigerant flow channel  53  may exit from the first outlet flow channel  53   b , flow to the suction flow channel  11   a  of the first compressor  11  through the heat recovery line  35 , and then be supplied to the first compressor  11 . Furthermore, the supercooled refrigerant stored in the receiver unit  54  may exit through the second outlet flow channel  54   a , flow to the suction flow channel  26   a  of the second evaporator  26 , and then be supplied to the second evaporator  26  in the state in which the refrigerant has been expanded by the second expansion device  25 . At least one of the opening degree time and opening degree amount of the second expansion device  25  may be controlled by a controller (not shown) so that there is an optimal amount of refrigerant within the refrigeration cycle circuit  2 . 
       FIG. 5  is a diagram showing a flow of a refrigerant when the heating operation and refrigeration operation of the air conditioner are performed at the same time according to an embodiment of the present disclosure. 
     Referring to  FIG. 5 , the air conditioner may simultaneously perform a heating operation for heating the interior of a room and a refrigeration operation for refrigerating food within the refrigeration inside unit I 2 . 
     That is, when the heating operation of the air-conditioning cycle circuit  1  is performed, the first compressor  11  may be driven and the air-conditioning cycle circuit  1  may discharge a refrigerant. The refrigerant discharged by the first compressor  11  may flow to the cooling/heating switching valve  12  through the discharge flow channel  11   b  of the first compressor  11 . The refrigerant that has flowed to the cooling/heating switching valve  12  may flow to the inside heat exchanger  16  through the air conditioner pipe  17 . Thus, when the heating operation of the air-conditioning cycle circuit  1  is performed, the inside heat exchanger  16  functions as the first condenser. 
     Some of the refrigerant that has passed through the inside heat exchanger  16  may flow to the outside heat exchanger  13  through the air-conditioning liquid line  18 . The remainder of the refrigerant that has passed through the inside heat exchanger  16  may flow to the cooling receiver  50  through the heat recovery liquid line  34 . 
     Some of the refrigerant passing through the inside heat exchanger  16  and that flows to the outside heat exchanger  13  through the air-conditioning liquid line  18  may be supplied to the outside heat exchanger  13  when the refrigerant has been expanded by the first expansion device  14 . Thus, when the heating operation of the air-conditioning cycle circuit  1  is performed, the outside heat exchanger  13  functions as the first evaporator. The refrigerant that has flowed to the outside heat exchanger  13  may be evaporated while it is thermally exchanged with outside air. The refrigerant evaporated by the outside heat exchanger  13  may flow to the cooling/heating switching valve  12  through the suction/discharge flow channel  13   a  of the outside heat exchanger  13 , and may be supplied to the first compressor  11  again through the suction flow channel  11   a  of the first compressor  11 . 
     In the refrigeration cycle circuit  2 , the second compressor  21  may be driven, and the refrigeration cycle circuit  2  may discharge a refrigerant. The refrigerant discharged by the second compressor  21  may flow to the second condenser  23  through the discharge flow channel  21   b  of the second compressor  21 . The refrigerant that has flowed to the second condenser  23  may flow to the second evaporator  26  through the suction flow channel  26   a  of the second evaporator  26 . 
     The refrigerant that has passed through the second condenser  23  may be supplied to the second evaporator  26  when the refrigerant has been expanded by the second expansion device  25 . Thus, the refrigerant that has flowed to the second evaporator  26  may refrigerate food within the refrigeration inside unit I 2  and may be evaporated, while it is thermally exchanged with air within the refrigeration inside unit I 2 . The refrigerant evaporated by the second evaporator  26  may be supplied to the second compressor  21  again through the suction flow channel  21   a  of the second compressor  21 . 
     The remaining refrigerant that belongs to the refrigerant passing through the inside heat exchanger  16  of the air-conditioning cycle circuit  1  and that has flowed to the cooling receiver  50  through the heat recovery liquid line  34  may be expanded by the heat recovery expansion device  34   a , may flow to the second refrigerant flow channel  53 , and may be gasified through a thermal exchange with the refrigerant that has passed through the second condenser  23  of the refrigeration cycle circuit  2  within the cooling receiver  50  while supercooling the refrigerant that has passed through the second condenser  23 . 
     Furthermore, the refrigerant that has passed through the second condenser  23  may be supercooled through a thermal exchange with the refrigerant flowing through the second refrigerant flow channel  53 , while flowing through the first refrigerant flow channel  52 . The refrigerant supercooled while flowing through the first refrigerant flow channel  52  may exit through the open upper end of the first refrigerant flow channel  52  and be stored in the receiver unit  54 . The refrigerant gasified while flowing through the second refrigerant flow channel  53  may exit from the first outlet flow channel  53   b , flow to the suction flow channel  11   a  of the first compressor  11  through the heat recovery line  35 , and be supplied to the first compressor  11  The supercooled refrigerant stored in the receiver unit  54  may exit from the second outlet flow channel  54   a , flow to the suction flow channel  26   a  of the second evaporator  26 , and be supplied to the second evaporator  26  when the refrigerant has been expanded by the second expansion device  25 . At least one of the opening degree time and opening degree amount of the second expansion device  25  may be controlled by the controller (not shown) so that there is an optimal amount of refrigerant within the refrigeration cycle circuit  2 . 
       FIG. 6  is a diagram showing a flow of a refrigerant when only the refrigeration operation of the air conditioner is performed according to an embodiment of the present disclosure. 
     Referring to  FIG. 6 , the air conditioner may perform only a refrigeration operation for refrigerating food within the refrigeration inside unit I 2 . That is, only the refrigeration cycle circuit  2  may operate. 
     The second compressor  21  of the refrigeration cycle circuit  2  may be driven, and the refrigeration cycle circuit  2  may discharge a refrigerant. The refrigerant discharged by the second compressor  21  may flow to the second condenser  23  through the discharge flow channel  21   b  of the second compressor  21 . The refrigerant that has flowed to the second condenser  23  may flow to the second evaporator  26  through the suction flow channel  26   a  of the second evaporator  26 . 
     The refrigerant that has passed through the second condenser  23  may be supplied to the second evaporator  26  when the refrigerant has been expanded by the second expansion device  25 . Thus, the refrigerant that has flowed to the second evaporator  26  may refrigerate food within the refrigeration inside unit I 2  and may be evaporated while it is thermally exchanged with air within the refrigeration inside unit I 2 . The refrigerant evaporated by the second evaporator  26  may be supplied to the second compressor  21  again through the suction flow channel  21   a  of the second compressor  21 . 
     Furthermore, since the air-conditioning cycle circuit  1  does not operate, the refrigerant that has passed through the second condenser  23  is not thermally exchanged while flowing through the first refrigerant flow channel  52 . Instead, the refrigerant may exit through the open upper end of the first refrigerant flow channel  52  and be stored in the receiver unit  54 . The stored refrigerant may exit through the second outlet flow channel  54   a , flow to the suction flow channel  26   a  of the second evaporator  26 , and be supplied to the second evaporator  26  when the refrigerant has been expanded by the second expansion device  25 . At least one of the opening degree time and opening degree amount of the second expansion device  25  may be controlled by the controller (not shown) so that there is an optimal amount of a refrigerant within the refrigeration cycle circuit  2 . 
       FIG. 7  is a plan sectional view showing another embodiment of the cooling receiver.  FIG. 8  is a perspective view showing the lower part of the cooling receiver shown in  FIG. 7 .  FIG. 9  is a perspective view showing the upper part of the cooling receiver shown in  FIG. 7 . Regarding the embodiment illustrated in  FIGS. 7-9 , for purposes of convenience, the same reference numerals are assigned to elements of the cooling receiver as those of the aforementioned embodiment shown in  FIGS. 2 and 3 , and a detailed description thereof is omitted and only differences are described. 
     Referring to  FIGS. 7, 8, and 9 , a receiver unit  54  may include a plurality of cooling units  51 . In the present embodiment, the receiver unit  54  includes two cooling units  51 . 
     A first inlet flow channel  52   a  and a second inlet flow channel  53   a  are disposed at the lower parts of the cooling units  51 , respectively. A pipe that is part of the suction flow channel  26   a  of the second evaporator  26 , and corresponds to a portion between the second condenser  23  and the cooling receiver  50 , may be branched into two pipes, and may be connected to the first inlet flow channels  52   a , respectively. The heat recovery liquid line  34  may be branched into two lines and connected to the second inlet flow channels  53   a , respectively. 
     The first outlet flow channel  53   b  may penetrate the upper end of the receiver unit  54  and may be branched into two flow channels within the receiver unit  54 . The two flow channels may be connected to the second refrigerant flow channels  53 , respectively. 
     As described above, the air conditioner and the cooling receiver of the air conditioner according to embodiments of the present disclosure can have a simpler (which is also less costly) and more compact structure, as well as improved refrigeration efficiency because the supercooler and the receiver are integrated. 
     The technical advantages of the present invention are not limited to the aforementioned advantages and other technical advantages that have not been described will be evidently understood by those skilled in the art from the following description. Those skilled in the art to which the present invention pertains will understand that the present invention may be implemented in other various forms without departing from the technical spirit or essential characteristics of the present invention. Accordingly, the aforementioned embodiments should be construed as being only illustrative not being limitative from all aspects. Furthermore, the scope of the present invention is defined by the appended claims rather than the detailed description. It should be understood that all modifications or variations derived from the meanings and scope of the present invention and equivalents thereof are included in the scope of the appended claims.