Patent Publication Number: US-7594411-B2

Title: Indoor unit for air conditioner

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This is a Divisional application of U.S. application Ser. No. 11/151,257 filed on Jun. 14, 2005, now U.S. Pat. No. 7,350,370 which claims benefit under 35 U.S.C. § 119 of Korean Patent Applications No. 10-2004-43876 filed in Korea on Jun. 15, 10-2004, No. 2004-76354 and No. 2004-76356 filed on Sep. 23, 2004, respectively, the entire contents of which are hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an air conditioner, and more particularly, to an indoor unit of an air conditioner such that a filter mounted on the front side of the indoor unit of the air conditioner and a filter frames for supporting the filter are mutually fixed and supported easily and thus assembling and disassembling are convenient and the appearance is elegant. 
     2. Description of the Related Art 
     An air conditioner is a device for maintaining optimized inside air according to purpose. For example, in the case where inside air becomes high temperature in summer, the air conditioner blows wind of low temperature to cool down the inside. On the contrary, in winter, the air conditioner blows warm wind of high temperature to heat the inside air. Also, recently, the air conditioner performs various functions of controlling humidity in the inside and purifying air. 
     The air conditioners are roughly divided into an integral type and a separation type. An integral type air conditioner has one unit as a whole and a separation type air conditioner separately has an indoor unit installed inside a space that needs air-conditioning and an outdoor unit installed in the outside. Particularly, recently, a separation type air conditioner is widely used considering noise and installation environment of an air conditioner. 
       FIG. 1  is an exploded perspective view of a separation type air conditioner of a related art and  FIG. 2  is a view illustrating air is sucked into and discharged from an indoor unit of a separation type air conditioner of a related art. 
     Referring to the drawings, a main chassis  1  forms a frame of an indoor unit. The main chassis  1  has a front panel  3  formed on a front side thereof to form the outer appearance of the indoor unit. The main chassis  1  having the front panel  3  is mounted on a wall in the inside. 
     A space in which parts that will be described below are mounted is formed between the main chassis  1  and the front panel  3 . 
     In the meantime, the outer appearance of the indoor unit formed by the main chassis  1  and the front panel  3  is protruded toward the front side as a whole as illustrated in  FIG. 1 . 
     A suction panel  7  having a front suction grill  5  is provided on the front of the front panel  3  to form a front appearance of the indoor unit. A hinge member (not shown) is provided at the upper end of the suction panel  7  to allow the suction panel  7  to rotate. 
     The front suction grill  5  is a path through which air sucked from a space that needs air-conditioning is sucked into the inside of the indoor unit. The front suction grill  5  is integrally formed with the suction panel  7 . In the meantime, an upper suction grill  3 ′ is formed long left and right on the upper side of the front panel  3 . The upper suction grill  3 ′ is integrally formed with the front panel  3  or separately formed. 
     A heat exchanger  9  is installed at the back of the front panel  3 . The heat exchanger  9  allows air sucked through the front suction grill  5  and the upper suction grill  3 ′ to exchange heat while passing through the exchanger  9 . A filter  9 ′ for purifying sucked air is installed on the front of the heat exchanger  9 . 
     A cross-flow fan  10  is installed at the back of the heat exchanger. The cross-flow fan  10  sucks air from a space that needs air-conditioning and discharges air back to the space that needs air-conditioning. A fan motor  10 ′ for providing rotational power to the cross-flow fan  10  is installed on the right side of the cross-flow fan  10  and a member for guiding flow created by the cross-flow fan  10  is further integrally formed in the inside of the main chassis  1 . 
     In the meantime, air that has heat-exchanged while passing through the heat exchanger  9  is discharged to a space that needs air-conditioning through the cross-flow fan  10 . For that purpose, a discharge grill  11  is installed at the lower end of the main chassis  1  and the front panel  3 . 
     In the meantime, a discharge port  13  for guiding air that has passed through the cross-flow fan  10  to a space that needs air-conditioning is formed in the inside of a discharge grill  11 . 
     A vane  15  for vertically controlling the direction of discharged air and a louver for horizontally controlling the direction of discharged air are installed in the inside of the discharge port  13 . The louver  16  is provided in plurals and the louvers  16  are connected to each other by a link  17  to operate simultaneously. 
     Also, a display part  19  for displaying an operation state of an air conditioner is provided at an about center on the lower portion of the front panel  3 . 
     In the meantime, a filter-mount part  20  is formed on left and right of the front frame  3 , respectively. The filter-mount part  20  has a pair of high performance filters  22 . The high performance filter  22  is supported by a filter frame  24 . That is, the quadrangular filter frame  24  having the high performance filter  22  is detachably mounted on the filter-mount part  20 . The high performance filter  22  has a singe function or various functions. 
     A filter knob  26  for allowing the filter frame  24  to be easily detached may be further provided on the lower end of the filter frame  24 . Though not shown, a fixing protuberance and a fixing groove that are formed to correspond to each other are provided to the filter frame  24  and the filter-mount part  20 , so that the filter frame  24  is coupled to the filter-mount part  20 . 
     Description will be made for the air conditioner having the above-described construction and operating in a cooling mode. 
     When the air conditioner operates, air for air-conditioning is sucked into the inside of an indoor unit by the cross-flow fan  10 . That is, air is sucked into the inside of the indoor unit through the front suction grill  5  and the upper suction grill  3 ′ to pass through the heat exchanger  9 . 
     The air that has passed through the heat exchanger  9  exchanges heat with working fluid flowing in the inside of the heat exchanger  9 . 
     The air that has exchanged heat with the heat exchanger  9  becomes relatively low temperature and is sucked into the cross-flow fan  10 . The air sucked into the cross-flow fan  10  is discharged to the lower direction and guided to the side of the discharge port  13 . 
     The air guided to the inside of the discharge port  13  changes a discharging direction thereof using the vane  15  and the louver  16  installed inside the discharge port  13  and is discharged to a space that needs air-conditioning through the discharge grill  13 . At this point, since the vane  15  and the louver  16  allow the discharged air to be distributed vertically and horizontally, the air is uniformly discharged to the space that needs air-conditioning. 
     To fix the heat exchanger  9 , a fixing bracket  8  is provided to the left of the main chassis  1  and a fixing end  8 ′ that corresponds to a screw-coupling end  9   a  of the heat exchanger  9  is provided to the right of the main chassis  1 . A screw-coupling hole  8 ″ should be punched in the inside of the fixing end  8 ′. 
     A receiving groove  8   a  for receiving a left end of the heat exchanger  9  is formed on the front side and the upper side of the fixing bracket  8 . Hookers  8   b  for hooking and fixing a left hairpin  9   c  of the heat exchanger  9  are protruded in the inside of the receiving groove  8   a.    
     A screw through hole  9   b  that corresponds to the screw-coupling hole  8 ″ is punched in the inside of the screw-coupling end  9   a  of the heat exchanger  9 . 
     The heat exchanger  9  is fixed by fixing the fixing bracket  8  in the left of the main chassis  1  using a screw S. At this point, the receiving groove  8   a  of the fixing bracket  8  is open toward the right side. 
     When the hairpin  9   c  of the heat exchanger  9  is inserted into the receiving groove  8   a  of the fixing bracket  8 , the hairpin  9   c  is hooked at and fixed in the hooker  8   b  of the inside of the receiving groove  8   a . At this point, the left end of the heat exchanger  9  is fixed first. 
     After that, the right side of the heat exchanger  9 , more specifically, the screw-coupling end  9   a  is closely attached to the fixing end  8 ′ of the main chassis  1  and the screen through hole  9   b  is coupled to the screw-coupling hole  8 ″ using a screw S, so that the heat exchanger  9  is fixed to the main chassis  1 . 
     To replace the high performance filter  22 , the filter frame  24  is raised and pulled to the lower side by taking the filter knob  26  formed thereon to separate the filter frame  24  from the filter-mount part  20 . After that, the filter frame  24  having a new high performance filter  22  is mounted. The filter frame  24  is mounted in the reverse order. 
     However, the related art has the following problems. 
     In the related art indoor unit of the air conditioner, the high performance filter  22  is fixed in the filter frame  24 . Accordingly, the high performance filter  22  is installed by fitting the filter frame  24  into the filter-mount part  20  of the front frame  3 . Since the filter frame  24  for supporting the high performance filter  22  should be separately provided in the related art, the number of parts increase and thus assembling processes and manufacturing costs increase. 
     Also, since the suction panel  7  constituting the front appearance of the indoor unit is formed in a straight-line in the related art air conditioner, the appearance of the indoor unit is not elegant. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention is directed to an indoor unit of an air conditioner that substantially obviates one or more problems due to limitations and disadvantages of the related art. 
     An object of the present invention is to provide an indoor unit of an air conditioner having, on one side of a suction port for sucking air, a high performance filter-mount part for fixing a high performance filter and a dust-collecting filter-fixing part for fixing a dust-collecting filter. 
     Another object of the present invention is to provide an indoor unit of a separation type air conditioner, having a filter frame integrally formed with the front frame, for fixing a high performance filter. 
     Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. 
     To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, there is provided an indoor unit of an air conditioner including: a main chassis constituting a rear appearance; a front frame formed on a front of the main chassis to constitute a front appearance; a heat exchanger and a fan disposed in an inner space of the main chassis; a front panel for shielding an entire surface of the front frame; a filter formed on a backside of the front panel, for filtering foreign substance; and a filter frame integrally formed with the front frame, for fixing the filter. 
     In another aspect of the present invention, there is provided an indoor unit of an air conditioner including: a main chassis constituting a frame and a rear appearance of the indoor unit; a heat exchanger and a fan disposed in an inner space of the main chassis; a front frame provided on a front of the main chassis and constituting a front appearance; and a front panel for shielding a front of the front frame, the front panel having an upper end rounded from the front to the back. 
     In a further another aspect of the present invention, there is provided an indoor unit of an air conditioner including: a main chassis constituting a rear appearance; a heat exchanger and a fan disposed in an inner space of the main chassis; a front frame formed on a front of the main chassis and constituting a front appearance, the front frame having: a suction port for sucking air of a space for air-conditioning; a high-performance filter-mount part formed on one side of the suction port, for fixing the high performance filter; a dust-collecting filter-fixing part formed on one side of the high-performance filter-mount part, for fixing the dust-collecting filter; and a discharge port formed on one side of the dust-collecting filter-fixing part, for discharging air that has been sucked to the suction port. 
     In a still further another aspect of the present invention, there is provided an indoor unit of an air conditioner including: a main chassis constituting a rear appearance; a heat exchanger and a fan disposed in an inner space of the main chassis; a front frame formed on a front of the main chassis and constituting a front appearance; a heat exchanger and a fan disposed in an inner space of the main chassis and the front frame; a front panel for shielding an entire surface of the front frame; filters formed on a backside of the front panel, for filtering foreign substance; and a filter frame integrally formed with the front frame, for fixing at least one of the filters. 
     It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
    
    
     
       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 embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings: 
         FIG. 1  is an exploded perspective view of a separation type air conditioner according to a related art; 
         FIG. 2  is a view illustrating air is sucked and discharged to and from an indoor unit of a separation type air conditioner according to a related art; 
         FIG. 3  is a perspective view of an indoor unit of an air conditioner according to the present invention; 
         FIG. 4  is an exploded perspective view of an indoor unit of an air conditioner according to the present invention; 
         FIG. 5  is an enlarged perspective view of a filter frame of the present invention, illustrating a state before a high performance filter is installed; 
         FIG. 6  is an enlarged perspective view of a filter frame of the present invention, illustrating a state in which a high performance filter is installed; 
         FIG. 7  is an enlarged perspective view of a front panel of an indoor unit of an air conditioner according to the second embodiment of the present invention; 
         FIG. 8  is a backside perspective view of a front panel of an indoor unit of an air conditioner according to the second embodiment of the present invention; 
         FIG. 9  is an exploded perspective view of an indoor unit of an air conditioner according to the third embodiment of the present invention; 
         FIG. 10  is an enlarged view of a high-performance filter-mount part and a dust-collecting filter-fixing part, illustrating a state in which the high performance filter and the dust-collecting filter are not mounted; and 
         FIG. 11  is an enlarged view of a high performance filter and a dust-collecting filter, illustrating a state in which the high performance filter is mounted and the dust-collecting filter is not mounted. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. 
     First Embodiment 
       FIG. 3  is a perspective view of an indoor unit of an air conditioner according to the present invention. 
     Referring to  FIG. 3 , the indoor unit  100  of the air conditioner includes a main chassis  110  constituting an entire frame and a rear appearance and a front frame  120  formed on the front of the main chassis  110  to constitute a front appearance, which constitute an appearance as a whole. 
     The front side of the front frame  120  is shielded by the front panel  130 . A suction grill  140  is formed on the upper side of the front panel  130 , namely, the upper surface of the front frame  120 . The front panel  130  is spaced a predetermined distance from the front frame  120 , so that outside air may flow through a gap between the front panel  130  and the front frame  120 . 
     In the meantime, the front panel  130  may be installed to rotate a predetermined angle forward with respect to the lower end as an axis. 
     A discharge port  122  is formed at the lower end of the front frame  120 . Accordingly, the air that has flowed into the inside of the indoor unit  100  is discharged to the outside of the indoor unit through the discharge port  122 . The discharge port  122  has a discharge grill  200  formed on an inside thereof. 
     A display window  124  is formed on the right upper end of the discharge port  122 . The display window  124  is transparent to allow a user to watch an operation state of the indoor unit  100  being displayed on a display part (not shown) of a discharge grill  200  that will be described below. 
       FIG. 4  is an exploded perspective view of an indoor unit of an air conditioner according to the present invention. The construction of the indoor unit  100  of the separation type air conditioner will be described in detail with reference to  FIG. 4 . 
     As described above, the indoor unit  100  includes the main chassis  110  and the front frame  120 , which constitute the appearance as a whole. The main chassis  110  is mounted on a wall surface in the inside. 
     Parts that will be described later are installed between the main chassis  110  and the front frame  120 . The appearance of the indoor unit formed by the main chassis  110  and the front frame  120  is protruded on the whole toward the front side as illustrated. 
     A fixing bracket  112  for fixing the left end of a heat exchanger  190  and a cross-flow fan  192  that will be described later is provided at the left end of the main chassis  110 . A fixing end  114  for fixing the right end of the exchanger  190  and the cross-flow fan  192  is protruded to the front. 
     A suction port  150  is formed on the front of the front frame  120 . The suction port  150  is a path through which air flows from the outside and has a filter frame  160  formed left and right thereof. The filter frame  160  is a part in which a high performance filter  170  is mounted and the filter frame  160  is formed in a pair left and right of the suction port  150 . That is, a center divider  152  that vertically crosses the suction port  150  is formed at the center of the suction port  150 . The filter frame  160  is formed on left and right of the center divider  152 , respectively. 
     The high performance filter  170  is mounted in the filter frame  160 . The high performance filter  170  is formed to have a single function or various functions. For example, referring to  FIG. 4 , the high performance filter  170  can include an ammonia filter  172  for deodorizing various odor such as a smoke, a formaldehyde filter  174  for removing a harmful ingredient generated from construction materials, and a toluene (VOC) filter  176  for deodorizing smell of volatile organic materials. Of course, various filters of other kind may be mounted therein. 
     The suction grill  140  is a path through which the air sucked from the space for air-conditioning is sucked into the inside of the indoor unit  100 . The suction grill  140  is formed to enclose the upper half of the suction port  150  of the filter frame  160 . The suction grill  140  is integrally coupled with a dust-collecting filter  180  and mounted on the front frame  120 . 
     The dust filter  180  is further installed between the front panel  130  and the front frame  120 . The dust-collecting filter  180  filters foreign substance contained in the air and is installed to enclose the suction port  150  as a whole. That is, the dust-collecting filter  180  has elasticity to cover the area ranging up to the upper end of the backside of the front frame  120  as well as the front side of the front frame  120 . The dust-collecting filter  180  is a filter different from the high performance filter  170  and collects foreign substance having a physical size of some extent such as a dust. The dust-collecting filer severs as a pre-filter for the high performance filter  170 . 
     The heat exchanger  190  is installed at the back of the front frame  120 . The heat exchanger  190  allows the air sucked through the suction grill  140  to exchange heat and has bending portions so as to correspond to the suction ports  150  of the front frame  120 . 
     The cross-flow fan  192  is installed on the back of the heat exchanger  190 . The cross-flow fan  192  sucks the air of the space for air-conditioning and discharges the air to the space. That is, the cross-flow fan  192  forces the outside air to flow through the suction port  150  and the air to discharge through the discharge port  122 . 
     A fan motor  194  for providing rotational power to the cross-flow fan  192  is installed on the right of the cross-flow fan  192  and the front side of the main chassis  110  may be formed at a curvature that corresponds to the outer periphery of the cross-flow fan  192  so as to easily guide airflow created by the cross-flow fan  192 . 
     The discharge grill  200  is provided in the inside of the lower end of the front frame  120 . The discharge grill  200  has a discharge port  202  for allowing the air that has exchanged heat at the indoor unit  100  to be discharged back to the outside. 
     The discharge grill  200  has a vane  204  for vertically controlling the airflow discharged through the discharge port  202  and a louver  206  for horizontally controlling the airflow. The louver  206  is provided in plurals. The louvers  206  are connected with each other by a link to operate simultaneously. 
     An auxiliary vane  208  for controlling a discharge direction of the air in cooperation with the vane  204  is further provided to the right end of the discharge grill  200 . A motor for forcibly rotating the auxiliary vane  208  depending on a operation state of the air conditioner is further installed on one side of the auxiliary vane  208 . A display part for displaying various information regarding the operation state of the air conditioner is formed on the upper side of the auxiliary vane  208 . 
       FIG. 5  is an enlarged perspective view of a filter frame of the present invention, illustrating a state before a high performance filter is installed. 
     Referring to  FIG. 5 , the construction of the filter frame  160  formed on the front frame  120  can be more clearly understood. As illustrated, the filter frame  160  is formed long horizontally and has an upper support  162  and a lower support  164  for supporting the upper end and the lower end of the high performance filter  170 , respectively. A center support  166  is provided between the upper support  162  and the lower support  164 . The center support contacts the backside of the high performance filter  170 . In the meantime, the upper support  162 , the center support  166 , and the lower support  164  are connected with one another by connection ribs  168  formed vertically with a predetermined interval. 
     Part of the upper support  162  is partially protruded to the front and the front end of the upper support  162  is bent downward to form a fixing protuberance  162 ′. Accordingly, the front upper end of the high performance filter  170  is hooked and fixed at the fixing protuberance  162 ′. In the meantime, the lower support  164  has lower protuberances  164 ′ spaced a predetermined interval and protruded to the front to support the lower end of the high performance filter  170 . 
     Description will be made for the indoor unit of the air conditioner having the above-described construction and operating in a cooling mode. 
     First, when the air conditioner operates, air for air-conditioning is sucked to the inside of the indoor unit by the cross-flow fan  192 . That is, when the fan motor  194  is operated by power applied from the outside to generate rotational power, the cross-flow fan  192  is rotated by the rotational power. When the cross-flow fan  192  rotates, suction force is created, so that outside air flows into the inside of the indoor unit  100  through the suction grill  140 . 
     The outside air that flows into the inside of the indoor unit  100  passes through the heat exchanger  190 . The air that passes through the heat exchanger  190  is cooled down by exchanging heat with working fluid flowing through the inside of the heat exchanger  190 . 
     The air that has exchanged heat at the heat exchanger  190  becomes the air of relatively low temperature to be sucked into the cross-flow fan  192 . The air sucked into the cross-flow fan  192  is discharged to the circumferential direction of the cross-flow fan  192  and then guided to the lower side. 
     The air guided to the lower side passes through the discharge port  202  of the discharge grill  200 . At this point, the discharge direction of the air is controlled by the vane and the louver  206  installed in the inside of the discharge port  202  control and the air is discharged to the space of air-conditioning. 
       FIG. 6  is an enlarged perspective view of a filter frame of the present invention, illustrating a state in which a high performance filter is installed. Referring to  FIGS. 5 and 6 , a detachment/attachment process of the high performance filter  170  will be clearly understood. 
     To mount the high performance filter  170  in the front frame, the high performance filter  170  is closely attached from the front lower side of the filter frame  160  first. That is, the upper end of the high performance filter  170  is pushed upward so as to be fitted in the upper support  162  of the filter frame  160  and then the lower end of the high performance filter  170  is closely attached to the lower support  164 . By doing this, the upper end of the high performance filter  170  is not prevented from being detached to the front by the fixing protuberance  162 ′ and the lower end is supported by and fixed at the lower support  164 . 
     Also, to detach the high performance filter  170  mounted in this manner, the lower end of the high performance filter  170  is detached from the lower support  164  by pulling the lower end a predetermined distance to the front. After that, the high performance filter  170  is lowered downward, the high performance filter  170  is completely detached from the filter frame  160 . 
     In the first embodiment, the high performance filter  170  is mounted in the filter frame  160  but this is only an exemplary one embodiment. Instead of the high performance filter  170 , a filter of other kind such as a general filter can be mounted on the front frame  120 . 
     Also, though an ammonia filter  172 , a formaldehyde filter  174 , and a toluene (VOC) filter  176  have been mentioned for an example of the high performance filter  170 , other filter having other function besides these filters can be applied, of course. 
     Also, in the above, the filter frame  160  is formed long on left and right of the suction port  150 , but the filter frame  160  can be formed vertically. Other detailed elements can be modified in various ways. 
     Second Embodiment 
     The second embodiment of the present invention is the same as the first embodiment except that a structure for allowing the front panel  130  to be easily assembled/disassembled is additionally formed. Therefore, description for same elements will be omitted. 
       FIG. 7  is an enlarged perspective view of a front panel of an indoor unit of an air conditioner according to the second embodiment of the present invention and  FIG. 8  is a backside perspective view of a front panel of an indoor unit of an air conditioner according to the second embodiment of the present invention. 
     Referring to  FIGS. 7 and 8 , the upper end of the front panel  130  is rounded backward at a predetermined angle. The reason the upper end of the front panel  130  is rounded is for allowing the front panel  130  to be easily detached when a user cleans the indoor unit  100  as well as making the appearance of the indoor unit  100  elegant. 
     That is, by rounding the upper end of the front panel  130 , both rounded sides of the front panel  130  is easy to grasp with hands when a user detaches the front panel  130 . Also, the hand&#39;s force applied to the front panel  130  is smaller more or less when a user detaches the front panel  130 . 
     Also, though not shown, a brand may be additionally attached on the rounded portion of the front panel  130  to make the appearance of the indoor unit  100  elegant even more. 
     A fixing protuberance  132  for fixing the front panel  130  on the front frame  120  is protruded backward from the backside of the front panel  130 . The fixing protuberance  132  includes an upper fixing protuberance  132   a  and a lower fixing protuberance  132   b  formed on the upper end and the lower end of the front panel  130 , respectively. The upper fixing protuberance  132   a  can be formed in plurals on the upper end of the backside of the front panel  130  and the lower fixing protuberance  132   b  can be formed as much as the number that corresponds to the upper fixing protuberances  132   a.    
     The fixing protuberance  132  is fixed in a main machine of the indoor unit, e.g., the front frame  120 , so that the front panel  130  can be fixed in the indoor unit as a whole and the position thereof can be stably maintained. 
     According to the second embodiment, since a user and an operator can conveniently detach and assemble the front panel, use convenience improves. 
     Third Embodiment 
       FIG. 9  is an exploded perspective view of an indoor unit of an air conditioner according to the third embodiment of the present invention. 
     Referring to  FIG. 9 , the inventive indoor unit includes a main chassis  310  and a front frame  320 , which constitute an appearance as a whole. The main chassis  310  is mounted on a wall surface in the inside. 
     Parts that will be described later are installed between the main chassis  310  and the front frame  320 . The appearance of the indoor unit formed by the main chassis  310  and the front frame  320  is protruded on the whole toward the front side as illustrated. 
     A fixing bracket  312  for fixing the left end of a heat exchanger  390  and a cross-flow fan  392  that will be described later is provided at the left end of the main chassis  310 . A fixing end  314  for fixing the right end of the exchanger  390  and the cross-flow fan  392  is protruded to the front. 
     A suction port  350  is formed on the front of the front frame  320 . The suction port  350  is a path through which air flows from the outside and has a high-performance filter-mount part  360  is formed left and right thereof. 
     The high-performance filter-mount part  360  is a part in which a high performance filter  370  is mounted and the high-performance filter-mount part  360  is formed in a pair left and right of the suction port  150 . That is, a center divider  352  that vertically crosses the suction port  350  is formed at the center of the suction port  350 . The high-performance filter-mount part  360  is formed on left and right of the center divider  352 , respectively. 
     The high performance filter  370  is mounted in the high-performance filter-mount part  360 . The high performance filter  370  consists of a multi-filter to have various functions. For example, referring to  FIG. 9 , the high performance filter  370  can include an ammonia filter  372  for deodorizing various odor such as a smoke, a formaldehyde filter  374  for removing a harmful ingredient generated from construction materials, and a toluene (VOC) filter  376  for deodorizing smell of volatile organic materials. The high performance filter  370  can be understood as a filter for collecting chemical foreign substance. 
     A dust-collecting filter-fixing part  380  for fixing a dust-collecting filter  388  is formed on the upper center of the high-performance filter-mount part  360 . The dust-collecting filter-fixing part  380  is formed in an about quadrangular shape and has side supports  382  on which the dust-collecting filters  388  provided in a pair left and right of the center divider  352  are seated and connection ribs  384  for connecting the side supports. 
     The dust-collecting filter  388  is mounted in the dust-collecting filter-fixing part  380 . The dust-collecting filter  388  emits negative ion. The negative ion sticks to harmful materials (mildew or toxic material coming out from a new house) to chemically react to them and remove the harmful material contained in the air. 
     Also, the dust-collecting filter  388  is formed to enclose the suction port  350  on the whole. That is, 
     The dust-collecting filter  388  has elasticity to cover the area ranging up to the upper end of the backside of the front frame  320  as well as the front side of the front frame  320 . 
     An air filter (not shown) may be further installed in the lower side of the dust-collecting filter  388  to filter relatively large foreign substance such as a dust, oil content, and moisture contained in air. 
     Since the dust-collecting filter-fixing part  380  and the high-performance filter-mount part  160  are elements for supporting the filters, they may be called a filter frame generally. 
     The suction grill  340  is a path through which the air sucked from the space for air-conditioning is sucked into the inside of the indoor unit. The suction grill  340  is formed to enclose the upper half of the suction port  350  of the high-performance filter-mount part  360 . 
     The heat exchanger  390  is installed at the back of the front frame  320 . The heat exchanger  390  allows the air sucked through the suction grill  340  to exchange heat and has bending portions so as to correspond to the suction ports  350  of the front frame  320 . 
     The cross-flow fan  392  is installed on the back of the heat exchanger  390 . The cross-flow fan  392  sucks the air of the space for air-conditioning and discharges the air to the space. That is, the cross-flow fan  392  forces the outside air to flow through the suction port  350  and the air to discharge through the discharge port  322 . 
     A fan motor  394  for providing rotational power to the cross-flow fan  392  is installed on the right of the cross-flow fan  392  and the front side of the main chassis  310  may be formed at a curvature that corresponds to the outer periphery of the cross-flow fan  392  so as to easily guide airflow created by the cross-flow fan  392 . 
     The discharge grill  400  is provided in the inside of the lower end of the front frame  320 . The discharge grill  400  has a discharge port  402  for allowing the air that has exchanged heat at the indoor unit to be discharged back to the outside. 
     The discharge grill  400  has a vane  404  for vertically controlling the airflow discharged through the discharge port  402  and a louver  406  for horizontally controlling the airflow. The louver  406  is provided in plurals. The louvers  406  are connected with each other by a link to operate simultaneously. 
     An auxiliary vane  408  for controlling a discharge direction of the air in cooperation with the vane  404  is further provided to the right end of the discharge grill  400 . A motor for forcibly rotating the auxiliary vane  408  depending on an operation state of the air conditioner is further installed on one side of the auxiliary vane  408 . A display part (not shown) for displaying various information regarding the operation state of the air conditioner is formed on the upper side of the auxiliary vane  408 . 
       FIG. 10  is an enlarged view of a high-performance filter-mount part and a dust-collecting filter-fixing part, illustrating a state in which the high performance filter and the dust-collecting filter are not mounted. 
     The high-performance filter-mount part  360  is formed long horizontally and includes an upper support  362  and a lower support  364  for supporting the upper end and the lower end of the high performance filter  370 , respectively. A center support  366  is provided between the upper support  362  and the lower support  364  and contacts the backside of the high performance filter  370 . The upper support  362 , the center support  366 , and the lower support  364  are connected to one another by a plurality of connection ribs formed vertically with a predetermined interval. 
     A portion of the upper support  363  is protruded partially toward the front and a front end of the protruded part is bent downward and forms a fixing protuberance  362 ′. Accordingly, the high performance filter  370  is hooked and fixed at the fixing protuberance  362 ′. The other hand, a lower protuberance  364 ′ is protruded with a predetermined interval toward the front at the lower support  362 . Moreover, the lower protuberance  364 ′ supports the lower end of the high performance filter  370 . 
     Next, description will be made for the inventive indoor unit of the air conditioner operating in a cooling mode. 
     Once the air conditioner operates, air for air-conditioning is sucked into the inside of the indoor unit by the cross-flow fan  392 . The cross-flow fan  392  is rotated by the rational power when a rotational power is generated from an operation of the fan motor with a voltage supplied from the outside. An outside air flows into the inside of the indoor unit through the suction grill by a suction force when the cross-flow fan  392  rotates. 
     The outside air flowing into the inside of the indoor unit passes through the heat exchanger  390 . As above, the air passing through the heat exchanger  390  is cooled down by exchanging heat with coolant passing through the inside the indoor unit. 
     The heat-exchanged air becomes a relatively low temperature at the heat exchanger  390  and is sucked into the cross-flow fan  392 . The air sucked toward the cross-flow fan  392  is discharged in a circumferential direction of the cross-flow fan and guided into the lower side. 
     The air guided to the lower side passes through a discharge port  402  of the discharge grill  400  and a discharge direction of the air is adjusted by the vane  404  and the louver  406  installed the inside of the discharge port  402  and discharged into the space for air-conditioning. 
       FIG. 11  is an enlarged view of a high-performance filter-mount part and a dust-collecting filter-fixing part, illustrating a state in which the high performance filter is mounted and the dust-collecting filter is not mounted. 
     Referring to  FIGS. 10 and 11 , the process of detaching the high performance filter  370  and the dust-collecting filter will be described in more detail. 
     The high performance filter  370  is closely attached to the front lower side of the high-performance filter-mount part  360  so as to attach the high performance filter  370  to the front frame  320 . That is, the upper end of the high performance filter  370  is closely attached to be fit into the upper support  362  of the high-performance filter-mount part  360  after pushing toward the upper and then the lower end of the filter  360  is closely attached on the lower support  364 . The upper end of the high performance filter  370  is not detached toward the front by the fixing protuberance  362 ′ and the lower end is supported and fixed by the lower support  364 . 
     The dust-collecting filter  388  inserts the dust-collecting filter-fixing protuberance  388   a  into a dust-collecting filter fixing-groove  386  formed on the lower end of the high-performance filter-mount part  360 . Then, the dust-collecting filter-fixing part  380  contacts the backside of the dust-collecting filter  388  and the rear upper end of the front frame  320  is installed to enclose the suction port  350  as a whole. 
     The dust-collecting filter  388  is pulled down so as to be detached after the dust-collecting filter-fixing protuberance  388   a  of the dust-collecting filter  388  gets out of the dust-collecting filter-fixing groove  386  to detach the high performance filter  370  and the dust-collecting filter  388 . Subsequently, the high performance filter  370  is completely detached from the high-performance filter-mount part  360  when the lower end of the high performance filter  370  is pulled toward the front a predetermined distance and the high performance filter  370  is pulled down. 
     A high-performance filter-mount part for mounting the high performance filter and a dust-collecting filter-fixing part for fixing the dust-collecting filter are integrally formed with the front frame as a filter frame, which form an entire appearance. Accordingly, since process for installing the high performance filter and the dust-collecting filter, and fixing means for fixing filters are not required, the number of processes and manufacturing cost reduce. 
     As described above, the high performance filter is fit into the indoor unit according to an embodiment of the present invention. Accordingly, an air conditioning of the indoor unit produces fresh air by filtering the foreign substance and the smell contained in the air. 
     Moreover, the filter frame having the high performance filter is integrally formed with the front frame. Accordingly, since process for installing the filter frame and fixing means are not required, the number of processes and manufacturing cost reduce. 
     Additionally, the upper end of the front panel forming a front appearance of the indoor unit is rounded backward in a predetermined angle. Consequently, the appearance of the indoor unit becomes elegant. 
     When cleaning the indoor unit and detaching the front panel, the rounded front panel can be grasped easily by hands with a small effort. 
     It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.