Patent Publication Number: US-2010123754-A1

Title: Array type print head cleaning apparatus, image forming apparatus having the same, and method of cleaning array type print head

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit under 35 U.S.C. §119(a) of Korean Patent Application No. 2008-114807, filed Nov. 18, 2008 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. 
     BACKGROUND 
     1. Field of the Invention 
     The present general inventive concept relates to an inkjet image forming apparatus. More particularly, the present general inventive concept relates to a cleaning apparatus of an array type print head usable with an array type inkjet image forming apparatus, and a method of cleaning the same. 
     2. Description of the Related Art 
     Generally, an array head type inkjet image forming apparatus is a type of inkjet image forming apparatus which uses ink to form images, and which includes a plurality of print heads fixed and arranged according to a size of a printing medium, in a direction transverse to a transferring direction of the printing medium. The plurality of print heads used in a conventional array head type inkjet image forming apparatus may be arranged in one or two rows to print on an entire area of the printing medium in the direction transverse to the transferring direction of the printing medium. Also, the array head type inkjet image forming apparatus may be configured so that the plurality of print heads is fixed so as not to move, with the printing medium being moved instead. 
     In a conventional inkjet image forming apparatus spraying ink via nozzles of the print head to form images, after a printing operation is performed, ink which is not moved to the printing medium may remain on the nozzles of the print head. Therefore, when the inkjet image forming apparatus has not been used for an extended period of time, the ink remaining on the nozzles may be solidified, thus clogging the nozzles of the print head so that the printing operation cannot be normally performed. In other words, when the inkjet image forming apparatus has not been used for a period of time, the remaining ink may react with outside air so as to be solidified on the nozzles of the print head. Also, the remaining ink may be solidified with contaminants, such as dust, to clog the nozzles. When the nozzle is clogged by the solidified ink and/or contaminants, the printing operation may not be performed normally. 
     Therefore, in order to perform a normal printing operation, the solidified ink clogging the nozzles of the print head must be removed. A print head cleaning apparatus, such as an ultrasonic cleaning apparatus, may be used to remove the solidified ink. 
     SUMMARY 
     The present general inventive concept provides an array type print head cleaning apparatus to clean a plurality of print heads arranged in two rows using a print head cleaning apparatus that cleans at least one print head arranged in one row, an image forming apparatus having the same, and a method of cleaning an array type print head. 
     Additional aspects and utilities of the present general inventive concept will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present general inventive concept. 
     The foregoing and/or other aspects and utilities of the present general inventive concept can be achieved by providing an array type print head cleaning apparatus, which may include: a cleaning carriage formed to linearly reciprocate; a cleaning unit to clean print heads and disposed to reciprocate between a first position and a second position in the cleaning carriage in a direction transverse to a moving direction of the cleaning carriage; and a cleaning unit moving mechanism disposed in the cleaning carriage to cause the cleaning unit to reciprocate between the first position and the second position. 
     The cleaning unit moving mechanism may include a rotation link coupled with the cleaning unit and a bar link disposed in the cleaning carriage and coupled with the rotation link, the bar link operating the rotation link so that the cleaning unit reciprocates between the first position and the second position. 
     The bar link may be disposed to linearly reciprocate in a direction transverse to a moving direction of the cleaning unit. 
     The cleaning carriage may include a guide bar guiding movement of the cleaning unit. 
     The rotation link may be formed substantially in a V-shape. 
     The rotation link may include a center portion disposed to rotate in the cleaning carriage; a first arm extending from the center portion, and coupled with the cleaning unit; and a second arm extending from the center portion, spaced apart from the first arm, and coupled with the bar link. 
     The second arm may include a coupling projection formed at a leading end of the second arm; and the bar link may include a coupling groove in which the coupling projection is disposed. 
     The rotation link may rotate in response to the bar link moving in a first direction, thereby causing the cleaning unit to move to the first position. 
     The rotation link may rotate in response to the bar link moving in a second direction, thereby causing the cleaning unit to move to the second position. 
     The cleaning unit may include an ultrasonic cleaning apparatus. 
     The foregoing and/or other aspects and utilities of the present general inventive concept may also be achieved by providing an image forming apparatus that may include: a main body; a print medium feeding unit disposed in the main body to feed a printing medium; an ink cartridge including a plurality of print heads arranged in a plurality of rows in a direction transverse to a transferring direction of the printing medium to spray ink; a cleaning unit disposed to move below the print heads and clean the print heads by row; a cleaning carriage configured to cause the cleaning unit to reciprocate in a direction transverse to a transferring direction of the printing medium; and a cleaning unit moving mechanism, disposed in the cleaning carriage, to cause the cleaning unit to move to a position below one row of the plurality of rows of print heads. 
     The cleaning unit moving mechanism may include a rotation link disposed in the cleaning carriage and coupled with the cleaning unit and a bar link disposed in the cleaning carriage to move parallel to a moving direction of the cleaning carriage, coupled with the rotation link, and including opposite ends thereof formed to project from the cleaning carriage, wherein the rotation link is rotated to move the cleaning unit in response to the bar link moving. 
     The cleaning unit may be moved to a position below a first row of the plurality of print heads in response to a first end of the bar link being affected by the main body, and the cleaning unit may be moved to a position below a second row of the plurality of print heads in response to a second end of the bar link being affected by the main body. 
     The foregoing and/or other aspects and utilities of the present general inventive concept may also be achieved by providing a method of cleaning an array type print head that may including cleaning a first row of print heads while causing a cleaning unit to move in a first direction transverse to a transferring direction of a printing medium; operating a cleaning unit moving mechanism to cause the cleaning unit to be moved to a position below a second row of the print heads cleaning the second row of the print heads while causing the cleaning unit to move in a second direction transverse to the transferring direction of the printing medium and operating the cleaning unit moving mechanism to cause the cleaning unit to be moved to a position below the first row of the print heads. 
     The operation of the cleaning unit moving mechanism to cause the cleaning unit to be moved to the position below the second row of the print heads may include: causing a first end of a bar link of the cleaning unit moving mechanism to contact a main body; causing the bar link to move in the second direction relative to the cleaning unit; causing the rotation link to be rotated by the bar link; and causing the cleaning unit to be moved to the position below the second row of the print heads by the rotation link. 
     The operation of the cleaning unit moving mechanism to cause the cleaning unit to be moved to the position below the first row of the print heads may include: causing a second end of a bar link of the cleaning unit moving mechanism to contact a main body; causing the bar link to move in the first direction relative to the cleaning unit; causing a rotation link to be rotated by the bar link; and causing the cleaning unit to be moved to the position below the first row of the print heads by the rotation link. 
     The foregoing and/or other aspects and utilities of the present general inventive concept may also be achieved by providing an array type print head cleaning apparatus that may include a linearly reciprocating cleaning carriage and a cleaning unit provided in the cleaning carriage to linearly reciprocate in a direction substantially transverse to that of the cleaning carriage. 
     The array type print head may include a cleaning unit moving mechanism provided in the cleaning carriage to move the cleaning unit between a first position a second position according to a mechanical interaction with a structure of an image forming apparatus. 
     The first position may be below a first row of print heads and the second position may be below a second row of print heads. 
     The cleaning unit moving mechanism may include a reciprocating member to move in a direction parallel to that of the cleaning carriage. 
     The reciprocating member may be configured to extend from either end of the cleaning carriage, and the mechanical interaction may include contact between the structure of the image forming apparatus and the reciprocating member extending from the cleaning carriage. 
     The contact may stop movement of the reciprocating member during movement of the cleaning carriage, causing a coupling link coupled to the reciprocating member and the cleaning unit to move the cleaning unit. 
     The cleaning unit may clean a first row of print heads during movement of the cleaning carriage in a first direction, and clean a second row of print heads during movement of the cleaning carriage in a second direction. 
     The foregoing and/or other aspects and utilities of the present general inventive concept may also be achieved by providing a method of cleaning an array type print head that may include moving a cleaning unit in a first direction to clean a first row of print heads; and moving the cleaning unit in a second direction to clean a second row of print heads. 
     The cleaning unit may be disposed inside a linearly reciprocating carriage, and the cleaning unit may linearly reciprocate inside the carriage in a direction transverse to that of the carriage. 
     The foregoing and/or other aspects and utilities of the present general inventive concept may also be achieved by providing an array type print head cleaning apparatus that may include a cleaning unit that moves in a first direction to clean a first row of print heads, and moves in a second direction to clean a second row of print heads. 
     Other advantages and salient features of the present general inventive concept will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses preferred embodiments of the present general inventive concept. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other features and advantages of the present general inventive concept will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which: 
         FIG. 1  is a perspective view illustrating an image forming apparatus including an array type print head cleaning apparatus according to an embodiment of the present general inventive concept; 
         FIG. 2  is a plan view illustrating an array type print head cleaning apparatus according to an embodiment of the present general inventive concept; 
         FIG. 3  is a partial perspective view illustrating an array type print head cleaning apparatus according to an embodiment of the present general inventive concept; 
         FIG. 4  is a partial plan view illustrating an array type print head cleaning apparatus according to an embodiment of the present general inventive concept in which a cleaning unit is located at a first position; 
         FIG. 5  is a partial side view illustrating the array type print head cleaning apparatus of  FIG. 4 ; 
         FIG. 6  is a partial plan view illustrating an array type print head cleaning apparatus according to an embodiment of the present general inventive concept in which a cleaning unit is located at a second position; 
         FIG. 7  is a partial side view illustrating the array type print head cleaning apparatus of  FIG. 6 ; 
         FIG. 8  is a plan view illustrating an array type print head cleaning apparatus according to an embodiment of the present general inventive concept in which a cleaning carriage approaches a second sidewall of a main body; 
         FIG. 9  is a plan view illustrating an array type print head cleaning apparatus according to an embodiment of the present general inventive concept in which a cleaning carriage approaches a first sidewall of a main body; and 
         FIG. 10  is a flowchart illustrating a method of cleaning an array type print head according to an embodiment of the present general inventive. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Reference will now be made in detail to the embodiments of the present general inventive concept, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present general inventive concept by referring to the figures. 
     Various matters discussed in this description, such as a detailed construction and elements thereof, are provided merely to assist in a comprehensive understanding of the present general inventive concept. Thus, it is therefore apparent that the present general inventive concept may be carried out without those discussed matters. Also, well-known functions or constructions are omitted in order to provide a clear and concise description of exemplary embodiments of the present general inventive concept. 
       FIG. 1  is a perspective view illustrating an image forming apparatus  1  including an array type print head cleaning apparatus  100  according to an embodiment of the present general inventive concept.  FIG. 2  is a plan view illustrating the array type print head cleaning apparatus  100  according to an embodiment of the present general inventive concept.  FIG. 3  is a partial perspective view illustrating the array type print head cleaning apparatus  100  according to an embodiment of the present general inventive concept. 
     Referring to  FIGS. 1 to 3 , the image forming apparatus  1  according to an embodiment of the present general inventive concept may include a main body  10 , a printing medium feeding unit  20 , an ink cartridge  30 , the array type print head cleaning apparatus  100 , and a control portion  200 . 
     The main body  10  forms much of an outer appearance of the image forming apparatus  1 , and supports the printing medium feeding unit  20 , the ink cartridge  30 , the array type print head cleaning apparatus  100 , and the control portion  200 . 
     The printing medium feeding unit  20  may store, for example, predetermined sheets of printing media P, and may pick up the sheets of the printing medium P one by one according to a signal from the control portion  200 . The picked up printing medium P may be transferred, as in this illustrated example, below the ink cartridge  30  by a transferring member such as a transferring roller  21 . 
     The ink cartridge  30  may form images on the printing medium P according to a signal from the control portion  200 , and may have a plurality of print heads  31 . The plurality of print heads  31  may be arranged in a direction transverse to a transferring direction of the printing medium (arrow A in  FIG. 2 ). Also, the plurality of print heads  31  may be arranged in one row, or in two rows or more, to print on the entire width of the printing medium P (said width indicated by dimension W in  FIG. 2 ) in a direction transverse to the transferring direction of the printing medium P. In the present embodiment, the plurality of print heads  31  are arranged in two rows. Hereinafter, the row of the print heads  31  positioned upstream of the transferring direction of the printing medium P (lower side in  FIG. 2 ) is referred as to a first row  32  of print heads  31 , and the row of the print heads  31  positioned downstream of the transferring direction of the printing medium P (upper side in  FIG. 2 ) is referred as to a second row  33  of print heads  31 . 
     In the bottom surface of each of the print heads  31  is formed a plurality of nozzles to spray ink onto the printing medium P. Structure and operation of the print heads  31  having the plurality of nozzles may be the same or similar to the conventional print head; therefore, detailed explanations thereof will be omitted. 
     The array type print head cleaning apparatus  100  may clean ink and/or contaminants remaining on the bottom surface of the plurality of print heads  31  of the ink cartridge  30  according to a signal from the control portion  200 , and may include a cleaning unit  110 , a cleaning carriage  120 , and a cleaning unit moving mechanism  140 . 
     The cleaning unit  110  may be provided below the print heads  31  of the ink cartridge  30 , and may clean the print heads  31 . The cleaning unit  110  may be formed to clean only one of the rows of print heads  32  or  33  among the print heads  31  arranged in the two or more rows  32  and  33 . In other words, while the cleaning unit  110  is moved by the cleaning carriage  120 , the cleaning unit  110  may clean only one of the rows of print heads  32  or  33  selected between the first row of print heads  32  and the second row of print heads  33 . 
     If the cleaning unit  110  is formed to clean only one of the rows of print heads  32  or  33 , the size of the cleaning unit  110  may be smaller than that of the cleaning unit  110  formed to clean both of the two rows of print heads  32  and  33  at the same time. The cleaning unit  110  may comprise various cleaning apparatuses as long as the cleaning apparatuses can clean the print heads  31 . In the present embodiment, an ultrasonic cleaning apparatus, which can dissolve and remove ink and/or contaminants solidified on the nozzles of the print heads  31 , may be used as the cleaning unit  110 . The ultrasonic cleaning apparatus uses ultrasonic waves to atomize a cleaning solution and spray the atomized cleaning solution onto the print heads  31 . 
     The cleaning carriage  120  may carry the cleaning unit  110  along the plurality of print heads  31 , and may be formed to linearly move in the direction transverse to the transferring direction of the printing medium P. The cleaning carriage  120  may be formed substantially in a rectangular enclosure. The cleaning unit  110  may be disposed inside the cleaning carriage  120 , and may be formed to linearly move along a guide bar  111  disposed in the cleaning carriage  120 . The guide bar  111  may be disposed in a direction transverse to a moving direction of the cleaning carriage  120 , that is, parallel to the transferring direction of the printing medium P. Therefore, the cleaning unit  110  may move between a first position and a second position inside the cleaning carriage  120  in the direction transverse to the moving direction of the cleaning carriage  120 . Here, the first position indicates a position at which the cleaning unit  110  can clean the first row of the print heads  32  located upstream of the transferring direction of the printing medium P, and the second position indicates a position at which the cleaning unit  110  can clean the second row of the print heads  33  located downstream of the transferring direction of the printing medium P. 
     Also, the cleaning carriage  120  may include a carriage driving unit  130 . The carriage driving unit  130  may cause the cleaning carriage  120  to move, and may include a belt  131 , driving pulley  132  and driven pulley (not illustrated, and may simply support the belt  131  at one non-driving, hence driven, end as a substantial mirror image of the driving pulley  132 ), and a driving motor  134  to rotate the driving pulley  132 . The driving pulley  132  and driven pulley support the belt  131  and cause the belt  131  to move, for example, in a reciprocating motion. 
     The cleaning carriage  120  may be fixed to the belt  131 . Therefore, while the belt  131  is moved by the driving pulley  132 , the cleaning carriage  120  also moves correspondingly with the belt  131 . A timing belt may be used as the belt  131 . Also, as illustrated in  FIGS. 2 and 3 , a carriage shaft  135 , to which the cleaning carriage  120  may be movingly coupled, may be disposed in close proximity to the belt  131  so that the cleaning carriage  120  stably moves with the belt  131 . The carriage shaft  135  may be supported by a first sidewall  11  and a second sidewall  12  of the main body  10 . 
     The cleaning unit moving mechanism  140  may be disposed in the cleaning carriage  120 , and may cause the cleaning unit  110  to move such that the cleaning unit  110  may be located at either of the first position and the second position. The cleaning unit moving mechanism  140  may include a rotation link  150  and a bar link  160 . 
       FIG. 4  is a partial plan view illustrating an array type print head cleaning apparatus according to an embodiment of the present general inventive concept in which a cleaning unit is located at the first position.  FIG. 5  is a partial side view illustrating the array type print head cleaning apparatus of  FIG. 4 .  FIG. 6  is a partial plan view illustrating an array type print head cleaning apparatus according to an embodiment of the present general inventive concept in which the cleaning unit is located at the second position.  FIG. 7  is a partial side view illustrating the array type print head cleaning apparatus of  FIG. 6 . 
     The rotation link  150  may be disposed in the proximity of the bottom surface  121  of the cleaning carriage  120 . One end of the rotation link  150  may be coupled with the cleaning unit  110 , and the other end of the rotation link  150  may be coupled with the bar link  160 . The rotation link  150  may be formed substantially in a V-shape. More particularly, the rotation link  150 , as illustrated in  FIG. 4 , may include a center portion  153  rotatably disposed near the bottom surface  121  of the cleaning carriage  120 , a first arm  151  that extends from the center portion  153  and is coupled with the cleaning unit  110 , and a second arm  152  that extends from the center portion  153 , is spaced apart by a predetermined angle from the first arm  151 , and is coupled with the bar link  160 . The center portion  153  of the rotation link  150  may be rotatably supported by a rotation shaft  154  disposed near the bottom surface  121  of the cleaning carriage  120 . A stud may be used as the rotation shaft  154 . Also, the angle between the first arm  151  and the second arm  152  of the rotation link  150  may be determined so that movement of the bar link  160  causes the cleaning unit  110  to move from the first position to the second position. A coupling hole  155  may be formed in a leading end of the first arm  151  of the rotation link  150 . A coupling bar  112  inserted in the coupling hole  155  of the rotation link  150  may be disposed at the bottom of the cleaning unit  110 . The coupling hole  155  of the rotation link  150  may have a cross sectional area larger than that of the coupling bar  112  of the cleaning unit  110 . Also, a coupling projection  156  may be formed at a leading end of the second arm  152  of the rotation link  150 . The bar link  160  may have a coupling groove  166  in which the coupling projection  156  is inserted. 
     The bar link  160  may operate the rotation link  150  so that the cleaning unit  110  is located at either of the first position and the second position, and may be disposed in the cleaning carriage  120  to move parallel to the moving direction of the cleaning carriage  120 . That is, the bar link  160  may be disposed in the cleaning carriage  120  and may linearly reciprocate in a direction transverse to a direction in which the cleaning unit  110  moves inside the cleaning carriage  120 . In the present general inventive concept, the bar link  160 , as illustrated in  FIG. 3 , is disposed at a side surface of the cleaning carriage  120  to perform a slidable movement with respect to the cleaning carriage  120 . Bar holes  122   a  and  123   a,  from which opposite ends  161   a  and  162   a  of the bar link  160  may respectively project, may be formed at a front surface  122  and a rear surface  123  of the cleaning carriage  120 , respectively. As a result, according to the moving direction of the cleaning carriage  120 , one of the opposite ends  161   a  and  162   a  of the bar link  160  may project from the cleaning carriage  120 . Therefore, as illustrated in  FIG. 4 , when a first end  161   a  of the bar link  160  is affected by the first sidewall  11  of the main body  10 , such as the first end  161   a  being prevented from projecting through the bar hole  122   a  due to interference from the first sidewall  11 , a second end  162   a  of the bar link  160  may be projected from the rear surface  123  of the cleaning carriage  120  through the bar hole  123   a.  When the second end  162   a  of the bar link  160 , as illustrated in  FIG. 6 , is similarly affected by the second sidewall  12  of the main body  10 , the first end  161   a  of the bar link  160  is projected from the front surface  122  of the cleaning carriage  120  through the bar hole  122   a.    
     Also, the coupling projection  156  of the second arm  152  of the rotation link  150  may be inserted in the coupling groove  166  of the bar link  160  so that the bar link  160  and the rotation link  150  are coupled with each other. Therefore, while the bar link  160  moves along the sidewall of the cleaning carriage  120 , the rotation link  150  rotates about the center portion  153  supported by the rotation shaft  154  due to being coupled to both the bar link  160  and the cleaning unit  110 , the cleaning unit  110  being fixed to the cleaning carriage  120  in the direction transverse to the transferring direction of the printing medium. The bar link  160  may be formed so as not to interfere with the rotation link  150 . In the present embodiment, to prevent interference with the rotation link  150 , as illustrated in  FIG. 5 , the bar link  160  is formed so that a first portion  161  of the bar link  160  is spaced apart from a second portion  162  of the bar link  160  in a vertical direction with respect to the bottom surface  121  of the cleaning carriage  120 . The bar link  160  is further formed, as illustrated in  FIG. 4 , so that the first portion  161  of the bar link  160  is spaced apart from the second portion  162  of the bar link  160  in the moving direction (arrow C) of the cleaning unit  110 . 
     The control portion  200  may control the driving motor  134  of the carriage driving unit  130  to move the cleaning carriage  120 , and may control the cleaning unit  110  to spray cleaning solution onto the print heads  31 . In other words, the control portion  200  may control rotational speed and rotation direction of the driving motor  134  so that the cleaning unit  110  cleans the plurality of print heads  31  of the ink cartridge  30 . The control portion  200  may control the image forming apparatus  1  to form predetermined images on a printing medium P. The process in which the control portion  200  controls the image forming apparatus  1  to form images may be the same or similar to the control portion of the conventional image forming apparatus. Therefore, a detailed description thereof is omitted. 
     Hereinafter, operation of the image forming apparatus  1  having the array type print head cleaning apparatus  100  according to an embodiment of the present general inventive concept will be explained with reference to the accompanying drawings.  FIG. 8  is a plan view illustrating an array type print head cleaning apparatus according to an embodiment of the present general inventive concept in which a cleaning carriage approaches a second sidewall of a main body.  FIG. 9  is a plan view illustrating an array type print head cleaning apparatus according to an embodiment of the present general inventive concept in which a cleaning carriage approaches a first sidewall of a main body. 
     When standing by for a printing operation, the cleaning carriage  120  of the array type print head cleaning apparatus  100  may be located at a home position  13  provided in the first sidewall  11  of the main body  10 . The plurality of print heads  31  of the ink cartridge  30  may be covered by a capping module (not illustrated). Therefore, the plurality of print heads  31  may be protected in an airtight state. When the printing operation starts, the capping module covering the print heads  31  moves to expose the nozzles of the print heads  31 . 
     After receiving a printing command, the control portion  200  performs a print preparing process. That is, the control portion  200  causes the capping module to move so that the nozzles of the print heads  31  are exposed. After the nozzles are exposed, the control portion  200  performs a spitting process to spray a small amount of ink via the nozzles. Then the wiping unit (not illustrated) performs a wiping operation with respect to the bottom surface of the print heads  31  in which the nozzles are formed. After the print preparing process finishes, a platen (not illustrated) moves near and below the plurality of print heads  31 , and sets in a position close to the bottom surface of the print heads  31 . 
     After that, the control portion  200  controls the printing medium feeding unit  20  to pick up a printing medium P and to transfer the printing medium P to a space between the plurality of print heads  31  and the platen. The nozzles of the print heads  31  spray ink to form predetermined images on the transferred printing medium P. 
     After the printing operation is finished, the control portion  200  causes the platen to move, thereby forming an empty space below the plurality of print heads  31 . Then, the wiping unit may be located below the plurality of print heads  31  to wipe the bottom surface of the plurality of print heads  31 . After the wiping operation is finished, the wiping unit may move out of the space below the print heads  31 , and the capping module may cover the bottom surface of the plurality of print heads  31  to prevent the nozzles from being exposed to air. 
     When the image forming apparatus  1  performs such a printing operation, some nozzles of the plurality of print heads  31  may be clogged with the previously discussed ink and/or contaminants. Ink which is not moved to the printing medium, and which remains on the nozzles of the print heads  31 , may react with air. The ink remaining on the nozzles may be solidified, or contaminants such as dust in the air may be solidified along with the ink so as to clog the nozzles of the print heads  31 . When the nozzles are clogged, the control portion  200  may use the array type print head cleaning apparatus  100  to perform a print heads cleaning process to remove the solidified ink or contaminants clogging the nozzles of the plurality of print heads  31 . When the ultrasonic cleaning apparatus is used as the cleaning unit  110 , the cleaning solution is atomized by the ultrasonic wave and is sprayed onto the print heads  31 . The sprayed cleaning solution dissolves the ink or contaminants solidified on the nozzles of the print heads  31 . 
     When a cleaning sensor (not illustrated) detects that the nozzles of the print heads  31  are clogged, the print head cleaning process may be started. Alternatively, a user may initiate the print head cleaning process. Alternatively, the control portion  200  of the image forming apparatus  1  may automatically start the print head cleaning process according to a specific standard, such as the number of pages that have been printed, a predetermined time that has passed, etc. 
     When the print head cleaning process starts, the control portion  200  may cause the capping module to cap the print heads  31  of the ink cartridge  30 , or the platen positioned near the print heads  31  for printing to move, thereby forming a space in which the cleaning carriage  120  can move below the plurality of print heads  31 . 
     After the space is formed below the plurality of print heads  31 , the control portion  200  controls the driving motor  134  so that the cleaning carriage  120  moves from the home position  13  to the space below the plurality of print heads  31 . When a motor shaft of the driving motor  134  rotates, the belt  131  is rotated by the driving pulley  132  so that the cleaning carriage  120  moves below the plurality of print heads  31 . When the cleaning carriage  120  is located at the home position  13  of the first sidewall  11 , the cleaning unit  110 , as illustrated in  FIGS. 2 and 4 , is located at the first position, that is, a position in which the cleaning unit  110  can clean the first row of the print heads  32 . As a result, while the cleaning carriage  120  moves from the home position  13 , the cleaning unit  110  cleans the first row of the print heads  32 . 
     When the cleaning carriage  120  approaches the second sidewall  12  of the main body  10 , as illustrated in  FIG. 8 , the second end  162   a  of the bar link  160  projecting from the rear surface  123  of the cleaning carriage  120  first contacts the second sidewall  12  of the main body  10 . In this state, when the motor shaft of the driving motor  134  continues to rotate in the same direction, the bar link  160  maintains a stationary state and only the cleaning carriage  120  moves to the second sidewall  12  until the rear surface  123  of the cleaning carriage  120 , as illustrated in  FIG. 6 , contacts or is located near the second sidewall  12 . In other words, while the bar link  160  is in a stationary state due to the contact with the second sidewall  12 , the cleaning carriage  120  continues to move in the same direction at least momentarily. As a result, the second end  162   a  of the bar link  160  is forced inside of the cleaning carriage  120  through the bar hole  123   a,  and the first end  161   a  of the bar link  160  is forced to project from the front surface  122  of the cleaning carriage  120  through the bar hole  122   a.  Thus, relative to the cleaning carriage  120 , the bar link  160  is displaced linearly toward the first sidewall  11  of the main body  10  (a second direction, arrow H) in a direction parallel to the moving direction of the cleaning carriage  120 . 
     While the bar link  160  is relatively displaced linearly in the second direction with respect to the cleaning carriage  120 , the rotation link  150  coupled with the bar link  160  is rotated in the counterclockwise direction (arrow B in  FIG. 8 ) about a point supported by the rotation shaft  154 . That is, when the bar link  160  is linearly displaced in the second direction relative to the cleaning carriage  120 , the coupling projection  156  of the second arm  152  of the rotation link  150  inserted in the coupling groove  166  of the bar link  160  is relatively displaced together with the bar link  160 . Accordingly, the rotation link  150  is rotated in the counterclockwise direction (arrow B) about the rotation shaft  154 . When the rotation link  150  rotates in the counterclockwise direction, the cleaning unit  110  coupled with the first arm  151  of the rotation link  150  is moved along the guide bar  111  in a direction of arrow C as illustrated in  FIG. 8 , and is relocated to the second position as illustrated in  FIG. 6 . 
     When the cleaning carriage  120  arrives at the second sidewall  12  of the main body  10 , the control portion  200  causes the motor shaft of the driving motor  134  to rotate in reverse so that the cleaning carriage  120  is moved back in the direction of the home position  13  of the first sidewall  11  of the main body  10 . At this time, since the cleaning unit  110  disposed in the cleaning carriage  120  is located at the second position, while the cleaning carriage  120  is returned to the home position  13 , the cleaning unit  110  cleans the second row of the print heads  33 . The control portion  200  may determine when to change the rotation direction of the motor shaft of the driving motor  134  by using, for example, a position sensor (not illustrated) sensing the position of the cleaning carriage  120 . Alternatively, the control portion  200  may use the moving speed and moving distance of the cleaning carriage  120  to determine when to change the rotation direction of the motor shaft of the driving motor  134 . 
     When the cleaning carriage  120  approaches the first sidewall  11  of the main body  10 , as illustrated in  FIG. 9 , the first end  161   a  of the bar link  160  projecting from the front surface  122  of the cleaning carriage  120  first contacts the first sidewall  11  of the main body  10 . In this state, when the motor shaft of the driving motor  134  continues to rotate in the same direction, the bar link  160  maintains a stationary state and only the cleaning carriage  120  moves to the first sidewall  11  of the main body  10  so that the front surface  122  of the cleaning carriage  120 , as illustrated in  FIG. 4 , contacts or is located near the first sidewall  11 . Then, the first end  161   a  of the bar link  160  is forced inside of the cleaning carriage  120  through the bar hole  122   a,  and the second end  162   a  of the bar link  160  is forced to project from the rear surface  123  of the cleaning carriage  120  through the bar hold  123   a.  Thus, relative to the cleaning carriage  120 , the bar link  160  linearly moves toward the second sidewall  12  of the main body  10  (a first direction, arrow G) in a direction parallel to the moving direction of the cleaning carriage  120 . 
     While the bar link  160  is relatively displaced linearly in the first direction with respect to the cleaning carriage  120 , the rotation link  150  coupled with the bar link  160  is rotated in the clockwise direction (arrow D in  FIG. 9 ) about the rotation shaft  154 . That is, when the bar link  160  is linearly displaced in the first direction relative to the cleaning carriage  120 , the coupling projection  156  of the second arm  152  of the rotation link  150  inserted in the coupling groove  166  of the bar link  160  is relatively displaced together with the bar link  160 . Accordingly, the rotation link  150  is rotated in the clockwise direction (arrow D) about the rotation shaft  154 . When the rotation link  150  rotates in the clockwise direction, the cleaning unit  110  coupled with the first arm  151  of the rotation link  150  is moved along the guide bar  111  in a direction of arrow E as illustrated in  FIG. 9 , and is relocated to the first position as illustrated in  FIG. 4 . 
     When the cleaning carriage  120  arrives at the home position  13 , the control portion  200  may control the wiping unit to wipe the bottom surface of the plurality of print heads  31  in which the plurality of nozzles are formed. At this time, because the ink and/or contaminants solidified on the bottom surface of the plurality of print heads  31  are dissolved by the cleaning solution, they are easily removed from the print heads  31  by the wiping operation of the wiping unit. 
     After the wiping operation is completed, the control portion  200  may cause the capping module to cover the print heads  31 , thereby preventing the nozzles from contacting air and/or contaminants. 
     Hereinafter, a method of cleaning the array type print head according to an embodiment of the present general inventive concept usable with an image forming apparatus  1  having the array type print head cleaning apparatus  100  will be explained with reference to accompanying  FIGS. 2 and 10 .  FIG. 10  is a flowchart illustrating a method of cleaning an array type print head according to an embodiment of the present general inventive. 
     In the image forming apparatus  1  having the plurality of print heads  31  arranged in two rows, the control portion  200  controls the cleaning carriage  120  so that the cleaning unit  110  moves in the direction from the home position  13  to the second sidewall  12  of the main body  10  of the image forming apparatus  1 , this direction being transverse to the transferring direction of the printing medium P (the first direction, arrow G in  FIG. 9 ). Concurrently, the control portion  200  controls the cleaning unit  110  to clean the first row of the print heads  32  (S 10 ). 
     When the cleaning carriage  120  approaches the second sidewall  12  of the main body  10 , the cleaning unit moving mechanism  140  is operated so that the cleaning unit  110  moves from below the first row of the print heads  32  to below the second row of the print heads  33  (S 20 ). 
     The process in which the cleaning unit moving mechanism  140  causes the cleaning unit  110  to move is explained in detail hereinafter. When the cleaning carriage  120  approaches the second sidewall  12  of the main body  10 , the second end  162   a  of the bar link  160  of the cleaning unit moving mechanism  140  contacts the second sidewall  12  of the main body  10 . After the second end  162   a  of the bar link  160  contacts the second sidewall  12  of the main body  10 , the bar link  160  is prevented from moving further, that is, the bar link  160  maintains a stationary state and the cleaning carriage  120  continues to move in the first direction (arrow G). By considering the cleaning carriage  120  to be in the stationary state, the bar link  160  moves, relative to the cleaning carriage  120 , in the direction of the first sidewall  11  of the main body  10  (the second direction). During this relative movement of the bar link  160  in the second direction (arrow H), that is, when the bar link  160  is in a stationary state and only the cleaning carriage  120  moves to the first direction, the rotation link  150  is rotated in the counterclockwise direction (arrow B) by the bar link  160 . When the rotation link  150  is rotated in the counterclockwise direction, the cleaning unit  110  is moved from a position below the first row of the print heads  32  to a position below the second row of the print heads  33 . At this time, the guide bar  111  guides the cleaning unit  110  to move from below the first row of the print heads  32  to below the second row of the print heads  33 . 
     When the cleaning unit  110  has moved from below the first row of the print heads  32  to below the second row of the print heads  33 , the control portion  200  controls the cleaning carriage  120  to move in reverse. In other words, the control portion  200  controls the cleaning unit  110  to move in the second direction (arrow H) transverse to the transferring direction of the printing medium P, and to clean the second row of the print heads  33  (S 30 ). 
     When the cleaning carriage  120  approaches the first sidewall  11  of the main body  10 , that is, when the cleaning carriage  120  is approaching at the home position  13 , the cleaning unit moving mechanism  140  is operated so that the cleaning unit  110  moves from below the second row of the print heads  33  to below the first row of the print heads  32  (S 40 ). 
     The process in which the cleaning unit  110  is moved by the cleaning unit moving mechanism  140  will be explained in detail as below. When the cleaning carriage  120  approaches the first sidewall  11  of the main body  10 , the first end  161   a  of the bar link  160  of the cleaning unit moving mechanism  140  contacts the first sidewall  11  of the main body  10 . After the first end  161   a  of the bar link  160  contacts the first sidewall  11  of the main body  10 , the bar link  160  cannot move further, that is, the bar link  160  maintains in a stationary state and the cleaning carriage  120  continues to move in the second direction (arrow H). By considering the cleaning carriage  120  to be in the stationary state, the bar link  160  moves, relative to the cleaning carriage  120 , in the direction of the second sidewall  12  of the main body  10  (the first direction). During this relative movement of the bar link  160  in the first direction (arrow G), that is, when the bar link  160  is in a stationary state and only the cleaning carriage  120  moves in the second direction (arrow H), the rotation link  150  is rotated in the clockwise direction (arrow D) by the bar link  160 . When the rotation link  150  is rotated in the clockwise direction, the cleaning unit  110  is moved from below the second row of the print heads  33  to below the first row of the print heads  32 . 
     After the cleaning carriage  120  returns to the home position  13 , the control portion  200  controls the wiping unit (not illustrated) to wipe the bottom surface of the print heads  31 . 
     An array type print head cleaning apparatus according to an embodiment of the present general inventive concept, an image forming apparatus having the same, and a method of cleaning the array type print head as described above may be formed to cause a cleaning unit, which is typically capable of cleaning one row of print heads, to clean two rows of print heads. Therefore, manufacturing cost and size of the cleaning unit may be reduced. 
     While the embodiments of the present general inventive concept have been described, additional variations and modifications of the embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims shall be construed to include both the above embodiments and all such variations and modifications that fall within the spirit and scope of the general inventive concept.