Patent Publication Number: US-10309683-B2

Title: Indoor unit of air conditioner

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The application claims priority under 35 U.S.C. § 119 and 35 U.S.C. § 365 to Korean Patent Application Nos.: 10-2015-0113503 (filed Aug. 11, 2015), 10-2015-0113499 (filed Aug. 11, 2015), and 10-2015-0113507 (filed Aug. 11, 2015), whose entire disclosures are hereby incorporated by reference. 
     BACKGROUND 
     1. Field 
     An inside unit of an air conditioner is disclosed herein. 
     2. Background 
     Generally, an air conditioner is a cooling and heating system which heats and cools a room by repeatedly suctioning inside air, exchanging heat with a low temperature or high temperature refrigerant, and then discharging the heat-exchanged air into the room. The air conditioner is an apparatus which forms a series of cycles and includes a compressor, a condenser, an expansion valve and an evaporator. 
     In particular, the air conditioner is divided into an outside unit (which may be referred to as an “outside side,” “heat radiating side,” or “outside unit”) which is installed at an outside, and an inside unit (which may be referred to as an “inside side,” “heat absorbing side,” or “inside unit”) which is mainly installed at an inside of a dwelling or building. The condenser (an outside heat exchanger) and the compressor are installed at the outside unit, and the evaporator (an inside heat exchanger) is installed at the inside unit. 
     The air conditioner may be classified into a separate type air conditioner in which the outside unit and the inside unit are separately installed, and an integral type air conditioner in which the outside unit and the inside unit are integrally installed. The separate type air conditioner is generally preferred in consideration of an installation space, a noise, or the like. 
     In a multi-type air conditioner among the separate type air conditioners, a plurality of inside units are generally connected to a single outside unit, and the inside units are installed in rooms to be air-conditioned, respectively, and thus an effect as if several air conditioners are installed may be obtained. One example of an inside unit of a multi-type air conditioner is an inside unit of a cassette type air conditioner, which is installed at a ceiling of an inside space and heats and cools the inside space. 
     Korean Patent Publication No. 10-2009-0006305, which is incorporated herein by reference, discloses an inside unit of a cassette type air conditioner installed in the ceiling. In order to fix the inside unit on the wall surface of the ceiling, it has a structure in which an installation means constituted with an anchor bolt and a bolt socket is mounted on an outside of a cabinet. In order to install, because a lower panel is mounted after the cabinet is mounted, the workability is degraded. In order to balance after installation or adjust other installation, the lower panel should be removed and then mounted again, etc., which significantly affects workability. 
     Korean Patent Publication No. 10-2008-0052927, which is incorporated herein by reference, discloses an inside unit of an air conditioner which forms an access hole on the four corners of a front surface panel, and which may control an installation state of the inside unit through accessing to an installation bracket through opening of the access hole. However, according to such a structure, for operating the installation means mounted on the installation bracket, because all four access hole covers should be opened or closed, there is a problem that the workability is poor. Because the four openable access holes are installed and an access hole cover should be mounted in a rotatable structure, there is a problem that not only the assembly work is increased, but also the productivity is decreased. 
     Korean Patent Publication No. 10-2009-0074374, which is incorporated herein by reference, discloses an inside unit of a cassette type air conditioner installed on the ceiling. The apparatus includes a fan, a heat exchanger, a fan motor, and a drain pan collecting condensed water of the heat exchanger are provided inside of a cabinet, and a structure in which a front panel shielding an opened surface of the cabinet is exposed to the ceiling surface. Also disclosed is a structure in which air is suctioned through an inlet port formed in the front panel and then discharged to an outlet port. According the inside unit of the air conditioner of such a structure, when the temperature of the discharged air is excessively lower than that of inside air, condensation on a surface of the outlet port may occur by the temperature difference and water generated by the condensation may drop into an inside space. 
     To prevent such a problem, an additional configuration for insulation or preventing dew condensation on the outlet port side may be added, but there is a problem that such a configuration is dropped or noise and vibration are generated by a continuous air flow. 
     In addition, an fan, a heat exchanger, a fan motor, and a drain pan collecting the condensed water of the heat exchanger are provided inside of a cabinet installed on the ceiling, and a control box is provided on one side of the drain pan, and a structure in which a front panel shielding a lower surface of the cabinet is exposed to the ceiling surface is disclosed. At the inside unit of the air conditioner of such a structure, for a service operation, such as maintenance or repair of the control box, the opened surface of the cabinet should be exposed by completely separating the front panel. Such configuration is problematic in that it requires that the front panel be separated and re-assembled upon every service operation. 
     SUMMARY 
     The present disclosure is directed to providing an inside unit of an air conditioner configured so that all the access holes which are accessible to a mounting bracket installed on a cabinet can be opened when a suction grille is opened, and thus the operation ease of a service may be improved. 
     According to an aspect of the present disclosure, there is provided an inside unit of an air conditioner, including a cabinet housing a fan and a heat exchanger, a front panel attached at an opening of the cabinet, the front panel forming an inlet port through which inside air is suctioned into a depressed inner side area, and an outlet port through which heat-exchanged air is discharged, a vane provided at the outlet port to control an opening degree of the outlet port, an air guide that extends along an outer side end of the outlet port, a slide preventing protrusion that protrudes from the front panel in which the air guide is mounted, and a protrusion accommodating groove formed at the bottom surface of the air guide to accommodate the slide preventing protrusion. 
     Also, the inside unit of the air conditioner of the present disclosure may include more than one slide preventing protrusion is formed to protrude along an end of the outlet port. 
     Also, the inside unit of the air conditioner of the present disclosure may include a guide surface formed in the air guide, the guide surface being curved to guide a flow of the air to the outlet port. 
     Also, the inside unit of the air conditioner of the present disclosure may include a side wall formed on the front panel for supporting a surface of the air guide, and a coupling groove formed on the side wall in which a coupling protrusion protruding from the air guide is inserted. 
     Also, the inside unit of the air conditioner of the present disclosure includes a mounting bracket provided at an outer side surface of the cabinet, an installation device coupled to the mounting bracket, a grille accommodating portion forming a panel opening formed to be depressed in the front panel, and through which the inside air is suctioned into the depressed inner side area, a suction grille to open and close the grille accommodating portion, the suction grille forming the inlet port, and an access hole that is opened at the grille accommodating portion so that the mounting bracket is exposed. 
     Also, the inside unit of the air conditioner of the present disclosure includes a drain pan assembly provided at an inner side of the cabinet, the drain pan assembly forming an air flow passage and collecting condensed water generated at the heat exchanger, a panel opening provided at a center of the front panel, a suction grille configured to open and close the panel opening and forming the inlet port, and a control box provided at the inner side of the cabinet and exposed to the panel opening. 
    
    
     
       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 perspective view of an inside unit of an air conditioner according to an embodiment of the present disclosure; 
         FIG. 2  is a exploded perspective view of the inside unit; 
         FIG. 3  is a exploded perspective view illustrating a combined structure of a suction grille and a front panel according to an embodiment of the present disclosure; 
         FIG. 4  is a sectional view of the opened suction grill; 
         FIG. 5  is a  5 - 5 ′ cross-sectional view of the  FIG. 4 ; 
         FIG. 6  is a partial cutout perspective view of the front panel; 
         FIG. 7  is a  7 - 7 ′ cross-sectional view of the  FIG. 4 ; 
         FIG. 8  is a perspective view of the opened suction grill; 
         FIG. 9  is a exploded perspective view of the front panel; 
         FIG. 10  is a partial perspective view of the front panel; 
         FIG. 11  is a perspective view of the air guide; 
         FIG. 12  is a partial perspective view of a state in which the air guide is mounted on the front panel; 
         FIG. 13  is a cross-sectional view of a state in which the air guide is mounted on the front panel; 
         FIG. 14  is a cross-sectional view illustrating the air flow of the inside unit; 
         FIG. 15  is a exploded perspective view of a drain pan assembly according to an embodiment of the present disclosure; 
         FIG. 16  is a perspective view of the control box; 
         FIG. 17  is a exploded perspective view of the control box; 
         FIG. 18  is a  18 - 18 ′ cross-sectional view of the  FIG. 16 ; 
         FIG. 19  is a perspective view of the opened control box; 
         FIG. 20  is a perspective view of the opened suction grille according to an embodiment of the present disclosure; 
         FIG. 21  is a perspective view of the opened control box. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It is understood that the description herein is not intended to limit the claims to the specific embodiments described. On the contrary, it is intended to cover alternatives, modifications, and equivalents as may be included within the spirit and scope of the present disclosure. 
       FIG. 1  is a perspective view of an inside unit of an air conditioner according to an embodiment of the present disclosure.  FIG. 2  is an exploded perspective view of the inside unit. 
     As shown, an inside unit  1  (hereinafter referred to as “inside unit”) may be configured with a cabinet  10  generally inserted into or attached to a ceiling of the inside surface, a front panel  20  provided at the lower end of the cabinet  10  and forming the external appearance of the bottom surface, and a suction grille  21 . The front panel  20  may be exposed to the lower side of the ceiling when the inside unit  1  is installed. 
     A heat exchanger  30  exchanging heat with the suctioned air, a fan  40  for suctioning and discharging the inside air, an orifice member  50  guiding the air suctioned toward a fan  40 , a drain pan assembly  60  collecting condensed water generated in the heat exchanger  30 , and a drain pump  70  for discharging the collected condensed water to the outside may be provided at the inside of the cabinet  10 . 
     As shown, the front panel  20  may be mounted or attached at the lower end of the cabinet  10 . The front panel  20  may be formed in a substantially rectangular shape when viewed from below. The front panel  20  may protrude further outside than the lower end of the cabinet  10 , and it may be configured so that a periphery of the front panel  20  is coupled with the lower surface of the ceiling. 
     A panel outlet port  22 , which is an exit port for the air discharged through the cabinet  10 , may be formed in the front panel  20 . The panel outlet port  22  may be formed at a position in which both sides of the front panel  20  are facing each other, and it may be formed at a position corresponding to the outer end of the cabinet  10 . The panel outlet port  22  may be formed longer along a lengthwise direction of the front panel  20 . Further, the panel outlet port  22  may be configured to be opened and closed by a vane  23  mounted at the front panel  20 . 
     The suction grille  21  may be mounted or attached at the central portion of the front panel  20 . The suction grille  21  may form a lower surface exterior portion of the inside unit  1 . The suction grille  21  may be located between the pair of the panel outlet ports  22 . The suction grille  21  may be formed in a plate which may shield the opening of a center of the front panel  20 . 
     The suction grille  21  forms a passage of an air inserted into the inside of the inside unit  1 . That is, at least a portion of the suction grille  21  is formed in a grille or grid-like configuration, and a plurality of inlet pots  213  may be formed so that the inflow of inside air is performed efficiently. 
     The cabinet  10  may be configured with an out plate  11  forming an exterior and an inner case  12  provided at the inner side of the out plate  11 . 
     The out plate  11  may be configured to form an appearance of the cabinet  10  through which the lower surface is opened by a steel material of plate. The out plate  11  may be formed through the configurations forming each surface are combined each other. Alternatively, the out plate  11  may be formed to be bent so as to have at least one surface. 
     Each two of mounting brackets  111  may be provided at both side surfaces of the out plate  11 . When the inside unit  1  is installed at an inside space, an installation device  2  may be attached to the mounting bracket  111 , and then the inside unit  1  may be installed in the inside space by the installation device  2 . 
     The installation device  2  may be fixed to a ceiling surface, and extended in a vertical direction. The device  2  may be configured with an anchor bolt passing through a mounting hole  111   a  of the mounting bracket  111 , and an anchor socket fastened to the anchor bolt passing through the mounting bracket  111 . Therefore, the installation device  2  may be mounted to be fixed respectively to the four mounting brackets  111  provided on the out plate  11 , and it may fix the inside unit  1 . It is understood that the installation device  2  is not limited to the foregoing configuration. 
     An installation position of the mounting bracket  111  may be located at the right and left sides from both sides surfaces, and it may be located at a vertically upward side of an access hole  25  of the front panel  20 , as described below. Therefore, access to the mounting bracket  111  is possible through the access hole  25 , and an operation such as mounting or changing installation position or horizontal operation of the inside unit  1  will be possible through the operation of the installation device  2 . 
     The inner case  12  may be formed at the inner side surface of the out plate  11 . The inner case  12  may be formed of an insulating material such as EPS (expended polystyrene) so as to insulate the interior of the cabinet  10  and prevent or reduce vibration noise. The inner case  12  may be in close proximity with the out plate  11  and form the shape of the interior of the cabinet  10 . Alternatively, the inner case  12  may be formed so that a surface which is in close proximity with the front panel  20  is completely opened. 
     The fan  40  may be provided at the inner side space of the inner case  12 , and the heat exchanger  30  may be disposed at the periphery of the fan  40 . The heat exchanger  30  may be disposed along the inner side surface of the inner case  12 . The heat exchanger  30  may be formed so as to be spaced apart from the wall surface and fan  40  of the inner case  12 . 
     Therefore, an air suctioned in the axial direction of the fan  40  may be discharged while rotating in the circumferential direction of the fan  40 , and it may exchange heat with a refrigerant while passing through the heat exchanger  30 . 
     A drain pan assembly  60  may be mounted or attached at an opened surface of the cabinet  10 . The drain pan assembly  60  may shield the opened surface of the cabinet  10 . The drain pan assembly  60  may have a structure seated on an upper end of the inner case  12 . 
     By the mounting of the drain pan assembly  60 , an outlet port  13  through which air communicated and heat-exchanged with the panel outlet port  22  is discharged may be defined at both sides of the cabinet  10 . And an inlet port opened so that air passing through the suction grille  21  and suctioned is directed toward the fan  40  side is formed at a center of the drain pan assembly  60 . 
     The drain pan assembly  60  may be configured with a body  61 , a pan plate  62  forming a surface facing an inner side of the inner case  12 , and the orifice member  50  mounted in a center of the body  61 . 
     The body  61  may be formed of the same material as that of the inner case  12 , and it may insulate the interior of the cabinet  10 . The body  61  may form the overall shape of the drain pan assembly  60 . 
     The orifice member  50  may be mounted at the center of the body  61 , and a panel inserting portion  612  may be formed to be depressed at one side in which the body  61  and the orifice member  50  are contacted. The panel inserting portion  612  may be formed at a position corresponding to a panel fixing portion  523  formed on the orifice member  50  when the orifice member  50  is mounted, and it forms a space at which a panel coupling portion  202  of the front panel  20  may be inserted. 
     The orifice member  50  may be mounted to the opened center of the body  61 . The orifice member  50  may comprise a plastic material that is formed by injection molding. An orifice hole  51  may be formed at a center of the orifice member  50 , and the suctioned air may be directed toward the fan  40  through the orifice hole  51 . 
     An edge having a predetermined height is formed on the periphery of the bottom surface of the orifice member  50 , and on the edge of the orifice member  50 , the panel fixing portion  523  may be formed at a position corresponding to the panel inserting portion  612 . 
     The panel inserting portion  612  and the panel fixing portion  512  form a coupling portion inserting port  524  by the orifice member  50  being mounted on the body  61 . The panel coupling portion  202  may be inserted through the coupling portion inserting port  524  to be hung with the panel fixing portion  523 . Therefore, the front panel  20  may have a structure that is fixed with one side of the drain pan assembly  60 . 
     A recessed portion  613  recessed at the inner side is formed at both sides surfaces of the body  61 . The recessed portion  613  may form the outlet port  13  when the drain pan assembly  60  is mounted. A box accommodating portion  614  providing a space in which a control box  80  may be disposed may be formed at the other side surface of the body  61 . 
     The pan plate  62  may be provided at a lower portion of the body  61 . The pan plate  62  may accommodate the lower portion of the body  61 , and form an entire lower surface of the drain pan assembly  60 . The pan plate  62  may be formed of a plastic material which is different from that of the body  61 , and form an outer appearance of the lower surface of the drain pan assembly  60 . 
     The pan plate  62  may have a structure through which the body  61  is press-fitted or bonded to the pan plate  62  and coupled to each other after injection molding of the plastic material. In addition, the pan plate  62  may be formed to be insert-injected when the body  61  is molded. Alternatively, the pan plate  62  and the body  61  may be integrally formed of a same material. 
     A space in which the condensed water is collected may be formed on the pan plate  62 , and an inlet side of the drain pump  70  is located in the pan plate  62  and may be configured to suction and discharge the collected condensed water. A heat exchanger accommodating portion in which an end portion of the heat exchanger  30  is received may be formed to be depressed at the pan plate  62 . 
     A control box seating portion  624  that is disposed on the box accommodating portion  614  side when coupled with the body  61 , so that the control box  80  may be seated in the control box seating portion  624 , may be formed at one side of the pan plate  62 . Although the control box  80  is provided on the control box seating portion  624 , it may be exposed to a panel opening  24  of the front panel  20  when the suction grille  21  is opened. 
       FIG. 3  is a exploded perspective view illustrating a combined structure of a suction grille and a front panel according to an embodiment of the present disclosure.  FIG. 4  is a sectional view of the opened suction grille.  FIG. 5  is a  5 - 5 ′ cross-sectional view of the  FIG. 4 .  FIG. 6  is a partial cutout perspective view of the front panel. 
     As shown in  FIGS. 3-6 , the front panel  20  may be formed having a rectangular shape that is larger than the size of the cabinet  10 . 
     A grille accommodating portion  201  depressed along the shape of the front panel  20  has generally rounded corners. The panel opening  24  may have a rectangular shape and be formed at an inner side center of the grille accommodating portion  201 . 
     The panel opening  24  may be configured to correspond to the size of the opened top surface of the cabinet  10 , and it may be configured so that the internal structure of the cabinet  10  is exposed. A coupling member, such as a screw, may be fastened to the periphery of the panel opening  24 , so that the cabinet  10  and the front panel  20  are firmly coupled to each other. 
     The panel coupling portion  202  may be formed at both sides of a side surface of the panel opening  24 . The panel coupling portion  202  is provided for fixing the front panel  20  to the cabinet  10 , more specifically, to the drain pan assembly  60 . The panel coupling portion  202  may be configured to be inserted into the coupling portion inserting port  524  formed in the drain pan assembly  60 . 
     The panel coupling portion  202  and the coupling portion inserting port  524  may provide a provisional fixing structure, so that the front panel  20  may maintain a temporary fixed state without falling down when the front panel  20  is mounted and disassembled. 
     The panel coupling portion  202  may be configured with a horizontal portion  202   a  that extends from an inside surface of the panel opening  24  to inside of the panel opening  24 , a vertical portion  202   b  extended downward from an end of the horizontal portion  202   a , and a hanging portion  202   c  protruding from an end of the vertical portion  202   b  to a side thereof. 
     As shown in  FIG. 5 , the panel coupling portion  202  is inserted in an inner side of the coupling portion inserting port  524  while the front panel  20  is coupled. The vertical portion  202   b  is inserted into the inner side of the coupling portion inserting port  524 , and the hanging portion  202   c  may be bonded or attached to the panel fixing portion  523 . In such configuration, the panel coupling portion  202  may maintain a fixed state in the drain pan assembly  60 . 
     The panel coupling portion  202  may be formed at the inside surface of the panel opening  24  facing each other, and disposed to cross each other and it may be formed so that the front panel  20  and the drain pan assembly  60  have a generally stable coupling structure. 
     The panel outlet port  22  may be formed at the grille accommodating portion  201  on the front panel  20 . The panel outlet port  22  may be located between the panel opening  24  and an outside end of the grille accommodating portion  201 . The panel outlet port  22  may extend along a length direction of the front panel  20 . 
     The panel outlet port  22  may extend along the outside end of the depressed grille accommodating portion  201 . Both ends of the panel outlet port  22  may have a rounded shape along the rounded edge of the grille accommodating portion  201 . A vane  23  for opening and closing the panel outlet port  22  may be provided on the panel outlet port  22 . The vane  23  may guide the discharge direction of heat-exchanged air discharged from the panel outlet port  22 . 
     An access hole  25  may be formed at both sides of the other grille accommodating portion  201  intersected with the panel outlet port  22 . The access hole  25  may be opened between the panel opening  24  and the outside end of the grille accommodating portion  201 . Two access holes  25  may be formed on each of both sides. 
     The access hole  25  may be formed to penetrate the front panel  20 , and communicate with the outside area of the cabinet  10 . In detail, the access hole  25  may be formed at a vertical lower portion of the mounting bracket  111  so that a user can manipulate the installation device  2 . Therefore, the mounting bracket  111  may be exposed through the access hole  25 . 
     At least a portion of the access hole  25  may be formed along the outside end of the grille accommodating portion  201 , and a pair of access holes  25  which are formed on the same side surface may be spaced apart from each other. An edge portion  251  extended toward the mounting bracket  111  side may be formed at the perimeter of the access hole  25 . The edge portion  251  prevents an unnecessary portion from being exposed toward the access hole  25  side. 
     A hinge device  212  connected with the suction grille  21  is provided in the grille accommodating portion  201 . The hinge device  212  is configured to rotate so that the suction grille  21  opens and closes the panel opening  24  and the access hole  25  simultaneously. Both side ends of the hinge device  212  may be rotatably connected to the front panel  20  and the suction grille  21 , and one pair of hinge devices  212  may be located in one direction of the suction grille  21 . 
     A restriction device  211  for maintaining a state in which the suction grille  21  is mounted to be fixed to the front panel  20  may be provided at the other side of the suction grille  21 . The restriction device  211  may be partially exposed to the outside of the suction grille  21 , and the suction grille  21  may be selectively released from the front panel  20  by the user&#39;s operation and may be rotatably configured. 
     The suction grille  21  may be formed to shield the panel opening  24  opened at the center of the front panel  20 . The suction grille  21  may be located at the inner side of the grille accommodating portion  201  of the front panel  20 , and it may be formed along an inner side end of the panel outlet port  22  and the outer side end of the grille accommodating portion  201 . In other words, the ends of both sides of the suction grille  21  may be formed to correspond to the inner side end shape of the panel outlet port  22 , and the ends of the other both sides of the suction grille  21  may be formed along the depressed line of the grille accommodating portion  201 . 
     Therefore, the suction grille  21 , when closed, may cover the grille accommodating portion  201  including the panel opening  24  and the access hole  25 , and may form an inner side end line of the panel outlet port  22 . In addition, it is spaced apart a predetermined distance from a depressed line of the grille accommodating portion  201  so that a line of the grille accommodating portion  201  may be viewed in a closed-loop shape through the exterior. 
     Hereinafter, a process for adjusting an installation state of the inside unit  1  according to an embodiment of the present disclosure having the above-described structure will be described with reference to  FIGS. 7 and 8 .  FIG. 7  is a  7 - 7 ′ cross-sectional view of the  FIG. 4 .  FIG. 8  is a perspective view of the opened suction grille. 
     When a service, such as an inspection or replacement of a PCB  83  is required while the inside unit  1  is mounted or attached to the ceiling, first the suction grille  21  is opened, as shown in  FIG. 8 . The suction grille  21  and the front panel  20  may be released by manipulating the restriction device  211 . An opposite side of the restriction device  211  is connected to the hinge device  212  and may be rotated by the hinge device  212  while being connected with the front panel  20 . 
     By such an operation, the grille accommodating portion  201  of the front panel  20  may be completely opened. Therefore, the opened surface of the cabinet  10  may be completely exposed through the panel opening  24 . Additionally, all of the four access holes  25  provided at both sides of the grille accommodating portion  201  may be completely opened. 
     The mounting bracket  111  and the installation device  2  attached with the mounting bracket  111  may be exposed through the access hole  25 . Therefore, the operator may control the coupling of the mounting bracket  111  and the installation device  2  by putting his or her hand into the access hole  25 . By controlling the coupling of each mounting bracket  111  and the installation device  2  through the four access holes  25 , the mounting state of the entire inside unit  1  may be adjusted. After controlling the mounting state of the inside unit  1 , the suction grille  21  may be rotated to simultaneously cover the panel opening  24  and the access hole  25  and be fixed at the front panel  20  by the restriction device  211 . 
       FIG. 9  is an exploded perspective view of the front panel. And  FIG. 10  is a partial perspective view of the front panel. 
     As shown in  FIGS. 9 and 10 , the front panel  20  includes a side wall  26  that extends in a vertical direction along one side surface of the panel opening  24 . The side wall  26  is extended vertically in the front panel  20  and may be used to support an air guide  28 , as described below. 
     A plurality of coupling grooves  261  may be formed on the side wall  26 . The coupling grooves  261  accommodate respectively coupling protrusions ( 282   a  in  FIG. 11 ) formed on the air guide  28 , and they may be spaced apart at predetermined intervals along a longitudinal direction. 
     An air guide mounting portion  27  on which the air guide  28  is seated may be formed between the side wall  26  and the panel outlet port  22 . A protrusion portion  271  protruding along the air guide mounting portion  27  may be formed on the air guide mounting portion  27 . For example, the protrusion portion  271  may be a portion of the air guide mounting portion  27  at which a portion of the suction grille  21  is accommodated when the suction grille  21  is mounted. As shown in  FIG. 10 , the air guide mounting portion  27  may be depressed at the front surface of the front panel  20 , and have a protruding shape at the rear surface of the front panel  20 . 
     A slide preventing protrusion  272  may be formed at an end of the air guide mounting portion  27  that is adjacent to the panel outlet port  22 . The slide preventing protrusion  272  is restricted to be hanged with one side of the air guide  28  mounted to the air guide mounting portion  27 , and prevents the air guide  28  from being pushed or moving out of the mounting position. More than one slide preventing protrusion  272  may be disposed along an outer side of the panel outlet port  22 , e.g., the end of the air guide mounting portion  27 . The more than one slide preventing protrusion  272  may be spaced apart at predetermined intervals. 
     A motor case mounting portion  203  may be formed at both sides of the panel outlet port  22 . The motor case mounting portion  203  may be used to mount motor cases  291  and  292  in which a vane motor  29  is accommodated. The motor case mounting portion  203  may be formed having a shape corresponding to one end of the motor cases  291  and  292 . A case fastening portion  204  may be formed at one side facing the motor case mounting portion  203 . The case fastening portion  204  may be formed having a shape of a boss to which a coupling member S is fastened. 
     Therefore, the motor cases  291  and  292  may be disposed at both sides of the panel outlet port  22 , and may be mounted to be fixed or attached by the motor case mounting portion  203  and the case fastening portion  204 . 
     The vane motor  29  may be provided inside of the motor cases  291  and  292 . The vane motor  29  may be provided on at least either one of the motor cases  291  and  292  of the right and left sides, and a rotation axis  231  formed on both side ends of the vane  23  and the vane motor  29  may be connected directly or indirectly. It is understood that when the vane motor  29  is not provided on the motor cases  291  and  292  of the left and right sides, the rotation axis of the vane  23  may be rotatably supported through a case hole of the motor cases  291  and  292 . 
     The air guide  28  guides air discharged toward the panel outlet port  22  side and at the same time, being formed of a heat insulating material such as polystyrene, prevents condensation from occurring in the panel outlet port  22  side. 
     The front panel  20  in which the air guide  28  is mounted may be formed of a material different from that of the air guide  28 . For example, the front panel  20  may be formed of a polypropylene material having excellent mold ability. Thus, when the front panel  20  is formed of a polypropylene material, since bending of the front panel  20  becomes severe relatively to the air guide  28 , the slide preventing protrusion  272  and the protrusion portion  271  are formed and a stable coupling state with the air guide  28  may be maintained. 
     Both ends of the air guide  28  may be fixed or attached by the motor cases  291  and  292  of both sides, and both sides of the motor cases  291  and  292  and the air guide  28  may be shielded by top covers  293  and  294 , respectively. For example, the top covers  293  and  294  may be fixed to the motor cases  291  and  292  or the front panel  20 . 
       FIG. 11  is a perspective view of the air guide. And  FIG. 12  is a partial perspective view of a state in which the air guide is mounted on the front panel.  FIG. 13  is a cross-sectional view of a state in which the air guide is mounted on the front panel. 
     As shown in  FIGS. 11, 12, and 13 , the air guide  28  is elongated along the air guide mounting portion  27 , and may be formed along the longitudinal direction of the panel outlet port  22 . The air guide  28  may be mounted or attached to an inner side surface of the front panel  20 . For example, the air guide  28  may be attached to the side wall  26  and the air guide mounting portion  27  by a glue, etc. and additionally, the both sides portions is pressed by the motor cases  291  and  292  and may be mounted to be fixed to the front panel  20 . 
     The air guide  28  may be formed so as to extend along an end of the panel outlet port  22 . The air guide  28  may be formed to include a lower surface  281  coupled with the air guide mounting portion  27 , a rear surface  282  supported by the side wall  26 , and a guide surface  283  guiding the discharged air to the panel outlet port  22  side. 
     The lower surface  281  may include a seating portion  281   a  corresponding to the protrusion portion  271  so as to be seated in the air guide mounting portion  27 . The seating portion  281   a  may be formed having a depressed shape in order to accommodate the protrusion portion  271 , and the lower surface  281  (except the seating portion  281   a ) may be formed to be in contact with the air guide mounting portion  27 . 
     A stepped portion  281   c  formed to be stepped may be further formed at a lower end of the seating portion  281   a , and the stepped portion  281   c  may form a predetermined space with the air guide mounting portion  27  when the air guide  28  is mounted. Such configuration is for preventing a noise generated upon expansions and contractions of the air guide  28  and the front panel  20  having different coefficients of the expansion according to the temperature difference caused by the discharged air during the operation of the inside unit  1 , and a free space may be provided when the air guide  28  or the front panel  20  is expanded and contracted. 
     A protrusion accommodating groove  281   b  may be formed at a front end of the lower surface  281 . The protrusion accommodating groove  281   b  may be formed at a lower surface of the air guide  28  corresponding to the slide preventing protrusion  272 . The protrusion accommodating groove  281   b  may be formed having a shape that is depressed to an end of the air guide  28 . Therefore, when the air guide  28  is mounted, such as shown in  FIG. 12  and  FIG. 13 , the slide preventing protrusion  272  may be received in the protrusion accommodating groove  281   b , and therefore, the air guide  28  may maintain a mounting state without sliding when the air is flowing. 
     The coupling protrusion  282   a  may be formed at the rear surface  282  of the air guide  28 . The coupling protrusion  282   a  may be formed to be accommodated in the coupling groove  261  of the side wall  26 , and may protrude more than the depth of the coupling groove  261 . Therefore, during the mounting of the air guide  28 , such as shown in the  FIG. 13 , the rear surface of the air guide  28  is spaced apart from the side wall  26  and may form a space. The space may prevent or significantly reduce noise generated from bumping during the expansion and contraction of the air guide  28  or the front panel  20  by the temperature difference. 
     The guide surface  283  is a surface connecting the lower surface of the air guide  28  in the upper surface of the air guide  28 . The guide surface  283  may be formed having a predetermined curvature and be rounded. Therefore, air discharged from the inner side of the cabinet  10  may flow along the guide surface  283  and may flow more efficiently into the panel outlet port  22 . In addition, the flowed air may flow along the guide surface  283 , and the heat transfer to an apposed area of the panel outlet port  22  may be blocked. 
     The lower end of the guide surface  283  may be formed along the inner side end of the panel outlet port  22 . The right and left side ends of the guide surface  283  may be formed to correspond to the curvature of the both sides of the panel outlet port  22  and guide air discharged to the both sides ends of the panel outlet port  22  also to be discharged more efficiently. 
     Case seating portions  284  and  285  depressed downward may be formed at the right and left sides of the air guide  28 . The motor cases  291  and  292  may be seated on the case seating portions  284  and  285 , and the case seating portions  284  and  285  may be formed to be depressed downward. 
     That is, the motor cases  291  and  292  may be seated on the case seating portions  284  and  285  while the air guide  28  is mounted on the air guide mounting portion  27 . In such configuration, a portion of the motor cases  291  and  292  may be accommodated in the case mounting portion  203 . By fastening a coupling member S penetrating the motor cases  291  and  292  to the case fastening portion  204 , the motor cases  291  and  292  may be mounted or fixed. By the fixed mounting of the motor cases  291  and  292 , the both ends of the air guide  28 , that is the case seating portions  284  and  285 , may be pressed to be in close contact with the front panel  20 . Therefore, the air guide  28  may be firmly fixed to the front panel  20  by the motor cases  291  and  292  without glue. 
     Hereinafter, an operation of the inside unit  1  according to an embodiment of the present disclosure having the above-described structure will be described.  FIG. 14  is a cross-sectional view illustrating the air flow of the inside unit. 
     As shown in  FIG. 14 , when the operation of the inside unit  1  begins, a motor for driving the fan  40  is rotated, and air in the inside space is suctioned into the inner side of the inside unit  1  through the inlet port  213  of the suction grille  21  by the rotation of the fan  40 . The suctioned air is suctioned into the center of the fan  40  through the orifice member  50 , and is discharged in a circumferential direction of the fan  40 . 
     The air discharged by the fan  40  is exchanging heat with a refrigerant while passing through the heat exchanger  30 , and guided to the panel outlet port  22  along a passage inside the cabinet  10 . At this time, the air directed to the panel outlet port  22  is guided by the air guide  28  and may be efficiently discharged to the panel outlet port  22 . 
     For example, air discharged by the guide surface  283  of the air guide  28  may be discharged to the outside with a directionality, and a direction discharged by the vane  23  is determined so as to be discharged to the inside space. During the process of passing through the air guide  28  insulated by the air guide  28 , the cold air does not directly contact an adjacent portion of the panel outlet port  22 , thereby preventing condensation. 
       FIG. 15  is an exploded perspective view of a drain pan assembly according to an embodiment of the present disclosure. As shown in  FIG. 15 , the drain pan assembly  60  may be configured with the body  61 , the pan plate  62  forming a surface facing the inner side of the inner case  12 , and the orifice member  50  mounted at the center of the body  61 . 
     A body opening  611  in which the orifice member  50  is mounted may be formed at the center of the body  61 . The front panel inserting portion  612  may be formed at the facing position of the inner side surface of the body opening  611 . 
     As shown, the recessed portion  613  depressed to the inner side surface of the body opening  611  is formed at both side surfaces of the body  61 . The box accommodating portion  614  providing a space in which the control box  80  may be disposed may be formed on the other side surface of the body  61 . 
     An orifice seating portion  623  protruding to the inner side of the body opening  611  may be formed at the center of the pan plate  62 . As shown, the orifice seating portion  623  may be formed in a shape corresponding to an orifice matching portion  513  formed on a bottom surface of the orifice member  50 , and may be configured to be supported while the orifice member  50  is seated. 
     The control box seating portion  624  disposed on the box accommodating portion  614  side when it is coupled with the body  61  may be formed at one side of the pan plate  62 . The control box  80  may be located on the box accommodating portion  614  while being seated on the control box seating portion  624 . As such, the control box  80  may be exposed to the panel opening  24  of the front panel  20  when the suction grille  21  is opened. 
     Hereinafter, the control box will be described in more detail an embodiment of the disclosure.  FIG. 16  is a perspective view of the control box an embodiment of the disclosure.  FIG. 17  is an exploded perspective view of the control box.  FIG. 18  is a  18 - 18 ′ cross-sectional view of the embodiment shown in  FIG. 16 . 
     As shown in  FIGS. 16-18 , the control box  80  may be configured with a box case  81  and a box cover  82 . The box case  81  provides a space in which other electrical components, including the PCP  83 , may be mounted therein. As shown in  FIG. 16 , a metal material in a plate shape may be bent and the upper surface may be formed in an opened box shape. 
     The box case  81  may be formed to have a shape corresponding to a shape of the control box seating portion  624  and the box accommodating portion  614 . In other words, the box case  81  may form one side surface of the drain pan assembly  60  while being mounted on the control box seating portion  624 . 
     A sub case portion  811  extended to the side may be formed at one side of the box case  81 . The sub case portion  811  provides an additional space in which the configurations added depending on the model of the inside unit  1  may be connected to the PCB  83 . 
     At least a portion of a cut-away portion  811   a  may be formed at the periphery of the sub case portion  811 , such that direct access to the out plate  11  side through the cut-away portion  811   a  is possible. A holder  811   b  for mounting separate wires may be mounted at the bottom surface of the sub case portion  811 . 
     Meanwhile, a box entrance  812  cut away to form a passage in which a wire connected with the configuration inside the inside unit  1  is entered may be formed at a portion of one side surface of the box case  81 . Therefore, the wire may be guided in an arranged state through the box entrance  812 , and may be connected with the PCB  83  inside the box case  81 . 
     At least one fastening portion  813  may be formed at the upper end of one side of both sides of the box case  81 . The fastening portion  813  may be formed to be bent inward so that the top of the box case  81  is vertical, and may form a surface in which the box cover  82  is seated. And, while the box cover  82  is seated, the coupling member S is fastened to penetrate the box cover  82  and the fastening portion  813 , so that the box case  81  and the box cover  82  may coupled. 
     A box coupling protrusion  84  may be formed at a top end of the other side of the box case  81 . As shown in  FIG. 17 , a plurality of box coupling protrusions  84  may be formed at the top end of the box case  81  at a position facing the fastening portion  813 , and may be spaced apart at regular intervals. 
     The box coupling protrusion  84  may extend from an upper end of the box case  81 , and may be bent vertically toward the inner side of the box case  81 . The box coupling protrusion  84  may be inserted into a cover coupling port  85  of the box cover  82  (described below) so that the box cover  82  is coupled to the box case  81 , and may be separated from the box case  81  or may open the box case  81  in a rotated and suspended form according to a user&#39;s manipulation. 
     The box coupling protrusion  84  may be configured with a bent portion  844  extended from the upper end of the box case  81  and a restriction portion  845  formed on an end of the bent portion  844 . The bent portion  844  may extend toward the inner side of the box case  81 . The bent portion  844  may be configured with a first extending portion  841 , a second extending portion  843 , and a connection portion  842  connecting the first extending portion  841  and the second extending portion  843 . The first extending portion  841  may be located below the second extending portion  843 , and may be connected with the upper end of the box case  81 . 
     Meanwhile, the restriction portion  845  may be formed at the end of the bent portion  844 . The restriction portion  845  prevents the box cover  82  from being arbitrarily extracted or removed. As shown, the restriction portion  845  may be shaped such that it has a greater width than a width of the bent portion  844 . 
     The box cover  82  shields the opened upper surface of the box case  81 , and is formed to shield the remaining portion except a portion of the sub case portion  811 . A sub cover portion  821  is formed at a side of the box cover  82 , and the sub cover portion  821  may shield a portion of the sub case portion  811 . As shown, one side of the sub cover portion  821  may be bent downward, and may form a shielding portion  821   a , and a guide portion  821   b  for the entry of the wire may be further formed on a center of the shielding portion  821   a.    
     A portion of an edge  822  of the box cover  82  may bent downward, and may be configured to be inserted to the inner side of the box case  81  so as to be in contact with a peripheral surface of the box case  81 . 
     A screw hole  823  may be formed at both sides of the box cover  82  seated on the fastening portion  813 , and a coupling member S such as a screw, may be fastened to the screw hole  823  so that the box cover  82  may be fixed or attached to the box case  81 . 
     The cover coupling port  85  may be formed at a peripheral side of the box cover  82 , more specifically, an end which is in contact with the box coupling protrusion  84  when the box cover  82  is mounted. There may be more than one cover coupling port  85  formed thereon. 
     The cover coupling port  85  may be configured with an upper opening portion  851  and a lower opening portion  852  forming one hole which has different vertical widths. The upper opening portion  851  and the lower opening portion  852  are connected to each other and form a single opening. 
     As shown in  FIG. 17 , the upper opening portion  851  may be located above the lower opening portion  852 . The upper opening portion  851  may have a narrower width than the width of the lower opening portion  852 . The width of the upper opening portion  851  may be greater than a width of the bent portion  844  and smaller than a width of the restriction portion  845 . Accordingly, when the bent portion  844  is located at the upper opening portion  851 , the movement of the box cover  82  is available, but the restriction portion  845  may be restricted without passing through the upper opening portion  851 . 
     The height of the vertical direction of the upper opening portion  851  may be lower than the vertical height of the bent portion  844 . Therefore, when the box cover  82  is pulled forward in the state in which the box cover  82  is closed (such as shown in  FIG. 6 ), the box cover  82  may not be easily separated from the box case  81  by the interference of the bent portion  844 . 
     The lower opening portion  852  may be located below the upper opening portion  851 . The width of the lower opening portion  852  may be larger than the width of the upper opening portion  851 . That is, the width of the lower opening portion  852  may be larger than the width of the restriction portion  845 , and therefore, when the box cover  82  is lifted so that the restriction portion  845  is located in the lower opening portion  852 , the end of the box coupling protrusion  84  passes through the cover coupling port  85  and may separate the box cover  82  from the box case  81 . 
       FIG. 19  is a perspective view of the opened control box according to an embodiment of the disclosure. As shown in  FIG. 19 , the box cover  82  constituting the control box  80  may be rotated when the box coupling protrusion  84  is inserted into the cover coupling port  85 , and may be suspended in the box case  81 . 
     The box cover  82  shields the opened surface of the box case  81  in the state shown in  FIG. 6 . In this state, the user releases the coupling member S and removes the engagement of the box cover  82  and the fastening portion  813 . The box cover  82  is then pulled frontward so that the box cover  82  is spaced apart from a side surface of the box case  81 , and then rotated. 
     The box cover  82  may open the box case  81  in the rotated state, such as shown in  FIG. 19 , and due to the nature of the position in which the box cover  82  is mounted, the box cover  82  may be vertically suspended with respect to a bottom surface of the box cover  82  by its own weight. 
     The outer side of the cover coupling port  85  becomes a seated state on the second extending portion  843 , and the box cover  82  maintains a suspended state. At this time, the bent portion  844  is located on the lower opening portion  852 . 
     Thus, when the box cover  82  is rotated and opened (such as shown in  FIG. 19 ), the box cover  82  is not easily separated by the interference of the bent portion  844 . In order to separate the box cover  82 , the lower opening portion  852  separates the box cover  82  while rotating and operating the box cover  82  so as to pass through the bent portion  844  and the restriction portion  845 . 
     Hereinafter, a service process of the control box  80  of the inside unit  1  according to an embodiment of the present disclosure having the structure as described above will be described.  FIG. 20  is a perspective view of the opened suction grille according to an embodiment of the present disclosure.  FIG. 21  is a perspective view of the opened control box. 
     As shown in  FIGS. 20 and 21 , when a service such as an inspection or replacement of the PCB  83  is required while the inside unit  1  is mounted on the ceiling, first the suction grille  21  is opened as shown in  FIG. 20 . 
     For opening the suction grille  21 , the restraint of the suction grille  21  and the front panel  20  is released by operating the restriction device  211 . In this situation, the opposite side of the restriction device  211  is connected to the hinge device  212 , and may be rotated by the hinge device  212  while being connected to the front panel  20 . 
     By this operation, the suction grille  21  may fully open the panel opening  24  of the front panel  20 , so that the inside of the cabinet  10  may be exposed through the panel opening  24 . The drain pan assembly  60  of the cabinet  10  and the control box  80  may be exposed through the panel opening  24 , and especially, the box cover  82  of the control box  80  may be exposed. 
     While the box cover  82  is exposed, the user may separate the coupling member S fastened to the box cover  82 . Through the separation of the coupling member S, the coupling of the box cover  82  and the fastening portion  813  is released, and the box cover  82  may be in a rotatable state. 
     While the box cover  82  is mounted, the box coupling protrusion  84  is inserted into the cover coupling port  85 , and in this situation, the user moves the box cover  82  by a predetermined distance along the bent portion  844  and rotates the box cover  82  while the circumference of the box cover  82  and the circumference of the box case  81  are spaced apart. 
     The interior of the box case  81  may be fully exposed by the rotation of the box cover  82 . The box coupling protrusion  84  has been rotated while being inserted into the inner side of the cover coupling port  85 , and since it maintains the inserted state into the cover coupling port  85 , the box coupling protrusion  84  maintains a suspended state to the box case  81  without being separated from the box case  81 . 
     At this time, because the box coupling protrusion  84  and the cover coupling port  85  are located at the end side of the panel opening  24 , when the box cover  82  is opened, the box cover  82  does not block the view of the operator and the interior of the box case  81  is visible. 
     In addition, a width of the box cover  82  is smaller than a width of the panel opening  24 , and even during the rotating operation of the box cover  82 , the box cover  82  is no longer interfered with the front panel  20 . 
     Meanwhile, when the service such as the inspection or replacement and repair of the PCB  83  is completed by the opening of the control box  80 , the operator may re-rotate and close the box cover  82 , fasten the coupling member S and fix the box cover  82  to the box case  81 . 
     Finally, the user may rotate the suction grille  21  to the original position and shield the panel opening  24 , and constrain the restriction device  211  to the front panel  20  so that the suction grille  21  is fixed to the front panel  20 . 
     According to the present disclosure having the configuration as described above may be expected have the following effects. 
     The suction grille is mounted to be openable and closable on the front panel, and the panel opening on the front panel and the access holes may be simultaneously opened by the opening and closing of the suction grille. In addition, the access holes may be respectively located at the vertical line of the mounting bracket, and thus the operation of an installation means coupled to the mounting bracket may be possible through the access holes. Therefore, the operation of the installation means may be possible by simply opening the suction grille without removing the entire front panel or opening the cover of the each access hole, so there is an advantage that an installation of the inside unit or a service after installation can be more easily performed. 
     In addition, as a suction grille configured for opening the panel opening of the front panel opens and closes the access hole at the same time, and controls the installation of the inside unit with a very simple structure, there is an advantage that the productivity and assembly workability are improved. 
     In addition, as the front panel may be fixed in such a manner that a panel coupling portion formed on the front panel is inserted into a hook coupling port of the drain pan assembly, there is an advantage that an operation during assembly and disassembly of the front panel is more easily and securely performed. 
     In addition, an air guide having a guide surface may be provided on the front panel in which an outlet port is formed so that discharged air flows more efficiently, and cooled air is prevented from being in direct contact with a region adjacent to the outlet port which improves insulation and blocks condensation from occurring. 
     In addition, as the air guide may be coupled to a slide preventing protrusion on the front panel, even when constant air flows, the air guide does not slide and may maintain the mounting position. Therefore, a noise due to vibration and trembling in accordance with the change of the mounting position of the air guide may be prevented or significantly reduced. 
     In addition, a space may be formed between with the air guide, a side wall contacted with the air guide and an outer side of an air guide mounting portion to have a free space when a portion of the air guide and the front panel is deformed by the difference in coefficient of expansion due to a difference in material by the temperature difference caused by the flowed air, and the space may prevent or significantly reduce a noise due to crash generated upon expansion or contraction deformation. 
     In addition, a motor case may be mounted at both sides of the air guide and the motor case may be fixedly mounted by pressing the both sides of the air guide, and thus the air guide may maintain a more stable and robust fixing state on the front panel. 
     And, for service of the control box, by opening the suction grille without an additional operation of separating the front panel, the access to the control box becomes available, and therefore, improves the serviceability of the control box. 
     And, for accessing to the control box, the suction grille may be fully opened with a minimum operation of the restriction device of the suction grille, and a mounting state of the suction grille may be maintained by a hinge device, thereby further improving the ease of the operation. 
     In addition, the control box may be configured with a box case and a box cover, and as the box cover is rotatably mounted but maintains a suspended state to the control box, the service work is more easily performed. 
     In addition, as the box cover opens the box case by rotating toward a close side to the end of the panel opening, the workability may be further enhanced by enabling access to the interior of the box case without interference by the box cover. 
     Although embodiments have been described with reference to a number of illustrative embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the preferred embodiments should be considered in descriptive sense only and not for purposes of limitation, and also the technical scope of the invention is not limited to the embodiments. Furthermore, the present disclosure is defined not by the detailed description but by the appended claims, and all differences within the scope will be construed as being comprised in the present disclosure.