Patent Publication Number: US-8991956-B2

Title: Ink jet recording device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority from Japanese Patent Application No. 2012-079813, filed on Mar. 30, 2012, the disclosure of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the invention 
     The disclosure relates generally to an ink jet recording device in which a recording head mounted on a carriage records an image on a sheet while the carriage is made to reciprocate. 
     2. Description of Related Art 
     A known ink jet recording device records an image on a sheet with a recording head being made to reciprocate along the sheet. The recording head is mounted on a carriage. The carriage is made to reciprocate by a driving force transmitted from a motor, in a direction intersecting the direction in which the sheet is conveyed. The recording head ejects ink while the carriage is reciprocating, to thereby record an image on the sheet. 
     SUMMARY OF THE INVENTION 
     Aspects of the disclosure provide an ink jet recording device capable of moving the carriage in a shorter time. 
     According to an embodiment of the disclosure, an ink jet recording device comprises a conveyor configured to convey a recording medium in a conveying direction; a carriage configured to reciprocate along a moving direction intersecting the conveying direction; a motor configured to drive the carriage; a recording head mounted on the carriage and configured to eject ink onto the recording medium; an encoder configured to generate a signal corresponding to movement of the carriage; and a controller configured to control a movement of the recording head and the motor according to the signal from the encoder. The controller is configured to perform: a recording control configured to control the recording head to eject the ink while the carriage is moving; and a first movement control configured to set a target stand-by position from which the carriage is configured to start moving in a particular direction and to control the motor to move the carriage to and stop at the target stand-by position. The controller is configured to control the carriage to move in the particular direction, when the carriage stops at a position upstream of the target stand-by position. In the particular direction in the first movement control, from the upstream position at which the carriage has stopped, and to perform the recording control during a period of continuous movement of the carriage across the target stand-by position. 
     According to an embodiment of the disclosure, a computer-readable storage medium stores computer-readable instructions that, when executed by a processor, cause a method to be performed, comprising: moving a recording head mounted on a carriage according to a signal from an encoder; ejecting ink from the recording head while the carriage is moving; and setting a target stand-by position from which the carriage is configured to start moving in a particular direction and moving the carriage to and stopping at the target stand-by position. Further, when the carriage stops at a position upstream of the target stand-by position in the particular direction, the carriage is moved in the particular direction from the upstream position at which the carriage has stopped, and ink is ejected from the recording head while the carriage is moving during a period of continuous movement of the carriage across the target stand-by position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present disclosure, needs satisfied thereby, and the objects, features, and advantages thereof, reference now is made to the following descriptions taken in connection with the accompanying drawings. 
         FIG. 1  is a perspective view depicting a multi-function device according to an embodiment of the disclosure. 
         FIG. 2  is a schematic drawing depicting a configuration of a printer unit according to an embodiment of the disclosure. 
         FIG. 3  is a functional block diagram of a control unit according to an embodiment of the disclosure. 
         FIGS. 4A to 4D  are diagrams depicting movement of a carriage when flushing is performed according to an embodiment of the disclosure;  FIG. 4A  depicting the carriage opposing a platen,  FIG. 4B  depicting the carriage positioned at a target stand-by position, and  FIGS. 4C and 4D  depicting the carriage deviated from the target stand-by position to the left and the right, respectively. 
         FIGS. 5A to 5C  are diagrams for depicting movement of a carriage when image recording is performed according to an embodiment of the disclosure;  FIG. 5A  depicting the image recording being performed on a recording region,  FIG. 5B  depicting the carriage positioned at a target standby position to perform image recording on another recording region, and  FIG. 5C  depicting the carriage made to move to another recording start position. 
         FIG. 6  is a flowchart representing a movement control process for the carriage performed by the control unit according to an embodiment of the disclosure. 
         FIG. 7  is a flowchart representing an image recording control process performed by the control unit according to an embodiment of the disclosure. 
         FIGS. 8A to 8C  are diagrams for depicting movement of the carriage when image recording is performed according to an embodiment of the disclosure;  FIGS. 8A and 8B  depicting the carriage deviated from the target stand-by position to the left and the right, respectively, and  FIG. 8C  depicting the carriage deviated to the right from the target stand-by position and frameless recording being performed on a recording region margin. 
         FIG. 9  is a flowchart representing a control process performed by the control for acceleration recording according to an embodiment of the disclosure. 
         FIG. 10  is a flowchart representing a frameless recording control process performed by the control unit according to an embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     Example embodiments are described in detail herein with reference to the accompanying drawings, like reference numerals being used for like corresponding parts in the various drawings. It is a matter of course that the following embodiment is merely exemplary, and may be modified in various manners within the scope of the disclosure. 
     Image recording may be performed by repeating a plurality of passes. The pass may include a series of actions from the start of the movement of the carriage to the ejecting of the ink from the recording head while the carriage is moving. To perform high-quality image recording, the carriage may be accelerated to a predetermined speed, from a target stand-by position, before the recording head may start ejecting the ink. 
     When moved to the target stand-by position, from which the carriage is to start moving, the carriage may be stopped at a position deviated from the target stand-by position, depending on the inertia or load exerted to the carriage or due to an error of motor current. With material degradation of the parts of the recording device over time, the deviation between the target stand-by position and the position where the carriage is actually stopped may increase. In addition, when the carriage is again made to move to the target stand-by position, it may take a longer time before the carriage reaches the correct position, which may lead to an increase in total time necessary for the image recording. Accordingly, certain aspects of the disclosure have been developed in view of the problems described above as well as other problems, 
     A multi-function device  10  may be placed as depicted in  FIG. 1  when in use. In this embodiment, three directions: top-bottom direction  7 , front-rear direction  8 , and left-right direction  9  are defined as indicated by arrows in  FIG. 1 . In the subsequent description, the top-bottom direction  7  may be described on the basis of the state where the multi-function device  10  is usably placed (see  FIG. 1 ) as reference; the front-rear direction  8  may be described on the basis of the position of an opening  13  being the near (front) side; and the left-right direction  9  may be described on the basis of the view of the multi-function device  10  from the near (front) side. 
     As depicted in  FIG. 1 , the multi-function device  10 , exemplifying the ink jet recording device according to the disclosure, may have a thin, generally rectangular block shape, and may include an ink jet printer unit  11 . The multi-function device  10  may have a printing function to record an image on a recording sheet  21  (see  FIG. 2 ), exemplifying the sheet according to the disclosure. The printer unit  11  may include a housing  14  having the opening  13  formed in the front face thereof, and a tray  20  (see  FIG. 2 ) on which recording sheets  21  of different sizes can be placed may be removably inserted through the opening  13 . An LCD panel  47  that displays various information for operation may be provided on the front face of the multi-function device  10 . 
     As depicted in  FIG. 2 , the printer unit  11  may include a feed unit  15 , a recording unit  24 , and so forth. The feed unit  15  may pick up the recording sheet  21  from the tray  20  and may supply the recording sheet  21 . The recording unit  24  may eject ink droplets onto the recording sheet  21  supplied by the feed unit  15 , thereby recording an image on the recording sheet  21 . 
     As depicted in  FIG. 2 , the feed unit  15  may include a feed roller  25 , a feed arm  26 , and a drive transmission mechanism  27 . The feed roller  25  may be driven to rotate by driving force of a feed motor  44  (see  FIG. 3 ) transmitted by the drive transmission mechanism  27  composed of a plurality of gears engaged with each other. The drive transmission mechanism  27  may be installed inside the feed arm  26 . The feed roller  25  may supply the recording sheet  21  to a curved path  42 A, described in more detail below. 
     As depicted in  FIG. 2 , the printer unit  11  may include therein a conveying path  42  formed from the leading end of the tray  20  (rear end) to a discharged sheet holder  43  through the recording unit  24 . The conveying path  42  may be sectioned into a curved path  42 A and a discharge path  42 B. The curved path  42 A may be the portion between the leading end of the tray  20  and the recording unit  24 . The discharge path  42 B may be the portion between the recording unit  24  and the discharged sheet holder  43 . 
     The curved path  42 A may be a curved passage extending from the vicinity of an inclined portion  22  of the tray  20  to the recording unit  24 . The recording sheet  21  supplied from the tray  20  may be bent so as to make a U-turn to the forward direction, guided through the curved path  42 A in a conveying direction (direction indicated by an arrow marked on dash-dot lines in  FIG. 2 ). Upon making the U-turn, the recording sheet  21  may be guided to be disposed under the recording unit  24 . The curved path  42 A may be composed of an outer guide member  18  and an inner guide member  19  opposing each other with a predetermined distance therebetween. The outer guide member  18 , the inner guide member  19 , and guide members  40  and  41 , which are subsequently described, all extend in the left-right direction  9  (depth direction in  FIG. 2 ). 
     The discharge path  42 B may be a linear passage extending from directly below the recording unit  24  to the discharged sheet holder  43 . The recording sheet  21  may be moved in the conveying direction along the discharge path  42 B. The discharge path  42 B may be composed of the recording unit  24  and a platen  30 , in the region where the recording unit  24  may be provided, the recording unit  24  and the platen  30  opposing each other with a predetermined distance therebetween. In the remaining region, the discharge path  42 B may be composed of an upper guide member  40  and a lower guide member  41  opposing each other with a predetermined distance therebetween. 
     The recording unit  24  may include a carriage  28  and a recording head  29  mounted on the carriage  28 , as depicted in  FIG. 2 . The carriage  28  may be supported by a first frame  51  and a second frame  52 . The first frame  51  and the second frame  52  may he generally of a plate shape having the longitudinal side oriented in the left-right direction  9 , and spaced from each other in the front-rear direction  8 . The carriage  28  may be made to reciprocate in the left-right direction  9  together with the recording head  29 , by a driving force from a carriage driving motor  45  (see  FIG. 3 ) transmitted through a drive transmission mechanism (not depicted), the carriage driving motor  45  exemplifying the motor according to the disclosure. In this operation, the first frame  51  and the second frame  52  may serve as a rail along which the carriage  28  may reciprocate. The left-right direction  9  is an example of the width direction according to the disclosure. 
     In the recording head  29 , a plurality of nozzles may be formed in a lower nozzle surface  53  (see  FIGS. 4A to 4D ,  5 A to  5 C, and  8 A to  8 C) opposing the platen  30 . The nozzles each may communicate with an ink cartridge (not depicted) in which one of cyan, magenta, yellow, and black ink may be stored. 
     The platen  30 , which may serve to retain or support the recording sheet  21  in a horizontal position, may be disposed under the recording unit  24  at the position opposing the recording unit  24  across the conveying path  42 . While reciprocating in the left-right direction  9 , the recording head  29  may eject ink supplied from the ink cartridge onto the recording sheet  21  conveyed over the platen  30 . Thus, an image may be recorded on the recording sheet  21  travelling along the conveying path  42 . 
     An ink collection tray  49  (see  FIGS. 4A to 4D ), exemplifying the tray according to the disclosure, may be provided on the left of the platen  30 . The ink collection tray  49  may be disposed so as to oppose the recording unit  24  across the conveying path  42  when the carriage  28  is shifted to the left from the reciprocating range for performing the image recording. At this position, the recording head  29  may be driven to eject air through the nozzle (an example of maintenance control according to the disclosure). Residual waste ink in the nozzle may be discharged together with air and may land on the ink collection tray  49 . The waste ink that has landed on the ink collection tray  49  may be sent to a waste ink tank (not depicted). The above operation may be performed for the purpose of nozzle maintenance of the recording head  29 , which may be called flushing. The flushing may be performed upon receipt of an instruction from the user, or at a predetermined timing. The ink collection tray  49  and a pump  50 , or the like, which causes the recording head  29  to eject air, exemplify a maintenance unit  60  according to the disclosure. 
     An optical linear encoder  64  (see  FIG. 3 ) exemplifying the encoder according to the disclosure may be provided on the carriage  28  and the second frame  52 . The linear encoder  64  may include a slender encoder strip (not depicted) having scales marked thereon in the left-right direction  9 , and a reading head (not depicted) that may read the scales on the encoder strip with an optical sensor (not depicted). The encoder strip may be provided on the second frame  52 . The reading head may be mounted on the carriage  28 , and the optical sensor may be disposed so as to oppose the surface of the encoder strip on which the scales may be marked. The output of the optical sensor may vary as the optical sensor relatively moves with respect to the scales on the encoder strip, with the movement of the carriage  28 . The reading head may convert the changes of the output of the optical sensor into pulse signals and may transmit the pulse signals to a control unit  130  (see  FIG. 3 ). 
     The image recording by the recording unit  24  may be performed by repetitions of a plurality of passes. The pass may include a series of actions from the start of the movement of the carriage  28  to the ejecting of the ink from the recording head  29  while the carriage  28  moves, which may be an example of the recording control according to the disclosure. By performing a pass, an image may be recorded on a region of the recording sheet  21  corresponding to the width of the nozzles aligned in the front-rear direction  8 . Upon completing each pass, the recording sheet  21  may be conveyed a predetermined distance by a first roller pair  33 , which is subsequently described, and the next pass may be performed. Thus, the image may be sequentially recorded on the recording sheet  21  from a downstream portion in the conveying direction. 
     The recording unit  24  may selectively perform one of a constant speed recording in which the recording head.  29  may eject the ink onto the recording sheet  21  while the carriage  28  is moving at a constant speed, and an acceleration recording in which the recording head  29  may eject the ink onto the recording sheet  21  while the carriage  28  is accelerating. When the carriage  28  is moving at a speed V 1  (e.g., the first speed according to the disclosure), the carriage  28  may be maintained at the constant speed and the constant speed recording may be performed. When the carriage  28  is moving slower than the speed V 1 , the carriage  28  may be accelerated and the acceleration recording may be performed. In the acceleration recording, the ejecting timing of the ink may be corrected according to the acceleration. The image recording described above may be performed under the control of the control unit  130 . The speed V 1  may be stored in a ROM  132  (see  FIG. 3 ) of the control unit  130 . 
     The recording unit  24  may be capable of performing the image recording so as to eject the ink onto a position outside of the edge of the recording sheet  21 . Accordingly, the recording unit  24  may be capable of performing the image recording without leaving a blank region on the periphery of the recording sheet  21  (hereinafter referred to as frameless recording). The ink that has landed on a position outside of the edge of the recording sheet  21 , (i.e., the ink that has landed on the platen  30 ) may be collected by an ink collection mechanism (not depicted) and sent to a waste ink tank. 
     As depicted in  FIG. 2 , the first roller pair  33 , including a first convey roller  31  and a pinch roller  32 , may be provided upstream of the recording unit  24  in the conveying direction. The pinch roller  32  may be disposed in press-contact with the surface of the first convey roller  31  by an elastic member, such as a spring (not depicted). The first roller pair  33  may pinch the recording sheet  21  fed through the curved path  42 A and may convey the recording sheet  21  to the platen  30 . 
     A second roller pair  36 , including a second convey roller  34  and a spur  35 , may be provided downstream of the platen  30  in the conveying direction. The spur  35  may be disposed. In press-contact with the surface of the second convey roller  34  by an elastic member, such as a spring (not depicted). The second roller pair  36  may pinch the recording sheet  21  having the image recorded by the recording unit  24  and may convey the recording sheet  21  to the downstream side in the conveying direction. 
     A third roller pair  39 , including a third convey roller  37  and a spur  38 , may be provided downstream of the second roller pair  36  in the conveying direction. The spur  38  may be disposed in press-contact with the surface of the third convey roller  37  by an elastic member, such as a spring (not depicted). The third roller pair  39  may pinch the recording sheet  21  conveyed by the second roller pair  36  and may convey the recording sheet  21  toward the discharged sheet holder  43 . 
     The first convey roller  31 , the second convey roller  34 , and the third convey roller  37  may be made to rotate by driving force of a convey motor  46  (see  FIG. 3 ) transmitted by a drive transmission mechanism (not depicted). The aforementioned roller pairs may exemplify the conveyor according to the disclosure. 
     The control unit  130  may control the overall operation of the multi-function device  1 . The control unit  130  may be realized as a microcomputer and may include a CPU  131 , a ROM  132 , a RAM  133 , an EEPROM  134 , and an ASIC  135 , which may be connected via an internal bus  137 . 
     The ROM  132  may contain a program to be performed by the CPU  131  to execute various operations including the recording control of the multi-function device  1 . The RAM  133  may serve as a storage region utilized by the CPU  131  to temporarily store data and signals to be used when executing the program, or as an operating region for data processing. The EEPROM  134  may store settings and flags to be maintained after power may be turned off. 
     The feed motor  44 , the carriage driving motor  45 , the convey motor  46 , the recording head  29 , the LCD panel  47 , and the linear encoder  64  may be electrically connected to the ASIC  135 . The ASIC  135  may be incorporated with a driver circuit that may control the respective motors. 
     The ASIC  135  also may receive the pulse signal outputted from the linear encoder  64 . The control unit  130  may calculate the travel distance and the position of the carriage  28  on the basis of the pulse signal from the linear encoder  64 , and may cause the carriage driving motor  45  to rotate such that the calculated travel distance and the position correspond to a target travel distance and a target position. 
     When the carriage  28  is made to move, the control unit  130  may set a target stand-by position at which the carriage  28  is to be stopped. The control unit  130  may control the rotation of the carriage driving motor  45  so that the carriage  28  stops at the target stand-by position. The target stand-by position for the flushing and image recording process are described in more detail below. In the following description, the position of the carriage  28  may be defined with reference to the right end of the nozzle surface  53 . Target stand-by positions P 1  and P 2 , a recording start position P 3 , and a landing limit position P 4  depicted in  FIGS. 4A to 4D ,  5 A to  5 C, and  8 A to  8 C also may be expressed as positions based on the right end of the nozzle surface  53 . In  FIGS. 5A to 5C , and  8 A to  8 C, the target stand-by position P 2 , the recording start position P 3 , and the landing limit position P 4  may be defined based on the carriage moving to the right in each pass. The target stand-by position may include a slight spatial margin, and may not necessarily be determined completely free from a predetermined margin of error, such that the target stand-by position may comprise a region. 
       FIGS. 4A to 4D  depict the target stand-by position P 1  for the flushing process. The target stand-by position P 1  may be the position where the carriage  28  may be disposed when air is ejected from the nozzle(s) of the recording head  29 . In  FIG. 4A , the carriage  28  may be disposed at the position opposing the platen  30 . When the condition for performing the flushing is satisfied, the control unit  130  may move the carriage  28  to the left as far as the target stand-by position P 1  depicted in  FIG. 4B  and may stop the carriage  28  at that position. When the carriage  28  is disposed at the position depicted in  FIG. 4B , the waste ink ejected from the nozzle(s) of the recording head  29  by the flushing may land on the ink collection tray  49 . The control to move the carriage  28  to the target stand-by position P 1  may be an example of the second movement control according to the disclosure. 
       FIGS. 5A to 5C  depict the target stand-by position P 2  for the image recording process. The target stand-by position P 2  may be the position from which the carriage  28  is to start moving, in each pass, to perform the image recording. Accordingly, the target stand-by position P 2  may be set for each pass.  FIGS. 5A to 5C  depict, however, that the target stand-by position P 2  may be set, for example, at the same position for all the passes. In  FIG. 5A , recording regions E 1  to E 4  may be specified on the recording sheet  21 . The recording regions E 1  to E 4  may represent the regions on the recording sheet  21  in which the image may be recorded in each pass.  FIG. 5A  depicts the state in which the carriage  28  may move to the right and the ink may be ejected onto the recording region E 2 . Upon completing the pass for the recording region E 2 , the pass for the recording region E 3  may be performed. After the pass for the recording region E 2  is finished, the control unit  130  may cause the recording sheet  21  to be moved in the conveying direction until the recording region E 3  overlaps the carriage  28  in the front-rear direction  8 . At the same time, the control unit  130  may move the carriage  28  as far as the target stand-by position P 2  depicted in  FIG. 5B  and may stop the carriage  28  at that position. The control to move the carriage  28  to the target stand-by position P 2  may be an example of the first movement control according to the disclosure. 
     The target stand-by position P 2  may be determined on the basis of the recording start position P 3  (see  FIG. 5C ) and a first acceleration distance L 1 . The recording start position P 3  may be the position at which the carriage  28  may be disposed when the recording head  29  starts ejecting the ink. Accordingly, the ink ejected when the carriage  28  is at the recording start position P 3  may land on the left end of the recording region of the current pass. The first acceleration distance L 1  may be the minimum distance necessary for the carriage  28  to reach the speed V 1  after starting the acceleration, 
     As depicted in  FIGS. 5B and 5C , the target stand-by position P 2  may be spaced to the left of the recording start position P 3  by the first acceleration distance L 1  Therefore, when the carriage  28  has started moving from the target stand-by position P 2 , the carriage speed is increased to the speed V 1  before reaching the recording start position P 3 . Thus, when the carriage  28  starts moving from the target stand-by position P 2 , the constant speed recording may be performed from the recording start position P 3 . 
     The movement control for the carriage  28  in the flushing and image recording process now will be described in more detail, with reference to the flowcharts depicted in  FIGS. 6 ,  7 ,  9 , and  10 . 
       FIG. 6  depicts the control process performed by the control unit  130  to move the carriage  28 . When the flushing or the image recording is performed, or when a predetermined condition is satisfied, the control unit  130  may set the target stand-by position. At S 110 , the control unit  130  may control the carriage driving motor  45  so as to move the carriage  28  to the target stand-by position and to stop the carriage  28  at that position. For example, the control unit  130  may check the signal from the linear encoder  64  while the carriage  28  is moving, and may determine whether to stop the rotation of the carriage driving motor  45  at a predetermined time interval. Upon stopping the rotation of the carriage driving motor  45 , the control unit  130  may confirm that the carriage  28  has stopped according to the signal from the linear encoder  64  (e.g., Yes at S 20 ). 
     When the movement at S 10  is for the flushing process (e.g., Yes at S 30 ), i.e., when the target stand-by position at S 10  is the target stand-by position P 1  depicted in  FIGS. 4A to 4D , the control unit  130  may determine whether the carriage  28  has stopped at the target stand-by position P 1 . This determination may be made according to whether a difference between the number of pulses outputted by the linear encoder  64  and the number of pulses that are supposed to be received when the carriage  28  accurately stops at the target stand-by position P 1  is within a predetermined threshold range. 
     For example, in  FIG. 4C , the carriage  28  may be shifted to the right by a distance L 2  from the target stand-by position P 1  in  FIG. 4D , the carriage  28  may be shifted to the left by a distance L 3  from the target stand-by position P 1 . When the threshold Lb utilized at S 110  is, for example, expressed as L 3 &lt;Lb&lt;L 2 , it may be determined that the carriage  28  has stopped at the target stand-by position in  FIG. 4D , and it may be determined that the carriage  28  has not stopped at the target stand-by position in  FIG. 4C . 
     When the carriage  28  is determined to have stopped at the target stand-by position P 1  (e.g., Yes at S 110 ), the flushing may be performed at S 160 . When the carriage  28  is determined not to have stopped at the target stand-by position P 1  (e.g., No at S 110 ), the control to move the carriage  28  to the target stand-by position P 1  may be performed again at S 120 . The control unit  130  may stop the rotation of the carriage driving motor  45  at a predetermined timing in the same manner as at S 20 , and then may confirm that the carriage  28  has stopped according to the signal from the linear encoder  64  (e.g., Yes at S 130 ). The control unit  130  may again determine whether the carriage  28  has stopped at the target stand-by position P 1 , and when the carriage  28  is determined to have stopped at the target stand-by position P 1  (e.g., Yes at S 140 ), the flushing may be performed at S 160 . When it is determined that the carriage  28  has not stopped at the target stand-by position P 1  (e.g., No at S 140 ), the carriage  28  has failed twice successively to stop at the target stand-by position. In this case, it may be presumed that the recording sheet  21  jammed in the conveying path  42  is impeding the movement of the carriage  28 . The control unit  130  may discontinue movement control of the carriage  28 , and may output an error message to be displayed on the LCD panel  47 , or on the display of a computer connected to the multi-function device  10  at S 150 , 
     When the movement at S 10  is for the image recording process (e.g., Yes at S 40 ), i.e., when the target stand-by position at S 10  is the target stand-by position P 2  depicted in  FIGS. 5A to 5C , the image recording control may be performed at S 50 . The image recording control will be described in more detail below. When the movement at S 10  is performed for a purpose other than the flushing and the image recording (e.g., No at S 40 ), the control unit  130  may determine whether the carriage  28  has stopped at the target stand-by position. When the carriage  28  is determined to have stopped at the target stand-by position (e.g., Yes at S 60 ), the carriage  28  may be made to stop moving. When the carriage  28  is determined not to have stopped at the target stand-by position (e.g., No at S 60 ), the carriage  28  again may be moved to the target stand-by position at S 70 . After the carriage  28  stops (e.g., Yes at S 80 ), the control unit  130  again may determine whether the carriage  28  has stopped at the target stand-by position at S 90 . When the carriage  28  is determined to have stopped at the target stand-by position (e.g., Yes at S 90 ), the control unit  130  may stop moving the carriage  28 , and when the carriage  28  is determined not to have stopped at the target stand-by position (e.g., No at S 90 ), the control unit  130  may output an error message to be displayed on the LCD panel  47  or on the display of a computer connected to the multi-function device  10  at S 100 . 
       FIG. 7  is a flowchart depicting a control process for the image recording. This flowchart corresponds to S 50  in  FIG. 6 . In the same manner as described above, the control unit  130  may determine whether the carriage  28  has stopped at the target stand-by position P 2 . When the carriage  28  is determined to have stopped at the target stand-by position P 2  (e.g., Yes at S 200 ), the control unit  130  may cause the carriage  28  to start moving from the current position at step S 290 . When it is determined that the carriage  28  has not stopped at the target stand-by position P 2 , but at a position beyond the target stand-by position P 2 , upstream thereof (see  FIG. 8A ) in the moving direction in the image recording process (i.e., to the right in  FIGS. 5A to 5C ; hereinafter referred to as recording direction) (e.g., Yes at S 210 ), the control unit  130  may cause the carriage  28  to move, at S 290 , from that position without stopping the carriage  28  at the target stand-by position P 2 . The control unit  130  then may cause the recording head  29  to eject the ink at S 300 . Since the speed of the carriage  28  has reached the speed V 1  upon reaching the recording start position P 3 , the constant speed recording may be performed. At S 310 , the control unit  130  may stop the carriage  28  at a predetermined position (e.g., a new target stand-by position for the next pass) downstream in the recording direction from the position where the recording head  29  finishes ejecting the ink. 
     When the carriage  28  is determined to have stopped at a position downstream of the target stand-by position P 2  (see  FIG. 8B ) in the recording direction (e.g., No at S 210 ), the control unit  130  may determine whether the carriage  28  has stopped at a position beyond the recording start position P 3 , upstream thereof in the recording direction. When the carriage  28  is determined to have stopped at the position upstream of the recording start position P 3  (see  FIG. 8B ) in the recording direction (e.g., Yes at S 220 ), the acceleration recording control may be performed. The acceleration recording control will be described in more detail below. When the carriage  28  is determined to have stopped at a position downstream of the recording start position P 3  in the recording direction (e.g., No at S 220 ), the image recording may not be able to be performed unless the carriage  28  is moved again, because the carriage  28  may be downstream of the recording start position P 3  in the recording direction. The control unit  130  again may move the carriage  28  to the target stand-by position P 2  at S 230 , and may confirm that the carriage  28  has stopped (e.g., Yes at S 240 ). When the carriage  28  is determined to have stopped at the target stand-by position at this point (e.g., Yes at S 250 ), the carriage  28  may be made to move in the recording direction and the recording head  29  may be caused to eject the ink, in the same manner as above in S 290  to S 310 . In this case, since the speed of the carriage  28  has reached the speed V 1  upon reaching the recording start position P 3 , the constant speed recording may be performed. 
     When the carriage  28  is determined not to have stopped at the target stand-by position (e.g., No at S 250 ), the control unit  130  may determine whether the carriage  28  has stopped at a position upstream of the recording start position P 3  in the recording direction. When the carriage  28  is determined to have stopped at the position upstream of the recording start position P 3  in the recording direction (e.g., Yes at S 260 ), the acceleration recording control may be performed at S 270 . When the carriage  28  is determined to have stopped at a position downstream of the recording start position  93  in the recording direction (e.g., No at S 260 ), the carriage  28  has stopped twice successively at the position downstream of the recording start position P 3  in the recording direction. At S 280 , the control unit  130  may discontinue movement control of the carriage  28 , and may output an error message to be displayed on the LCD panel  47 , or on the display of a computer connected to the multi-function device  10 , 
       FIG. 9  is a flowchart depicting a control process for the acceleration recording. This flowchart corresponds to S 270  in  FIG. 7 . The control unit  130  may determine whether the recording start position P 3  is upstream of the landing limit position P 4  (see  FIG. 8C ) in the recording direction. The landing limit position P 4  may be the boundary between whether or not the ejected ink lands on the recording sheet  21 . Since the position of the carriage  28  may be defined on the basis of the right end of the nozzle surface  53 , the landing limit position P 4  may correspond to the left edge of the recording sheet  21 . When the carriage  28  is upstream of the landing limit position P 4  in the recording direction (an example of the unrecordable range according to the disclosure), the ejected ink may not land on the recording sheet  21 , but may land on the platen  30 . When the carriage  28  is downstream of the landing limit position P 4  in the recording direction (an example of the recordable range according to the disclosure), the ejected ink may land on the recording sheet  21 . Thus, the recording start position P 3  being upstream of the landing limit position P 4  in the recording direction may allow frameless recording to be performed. Performing frameless recording may depend on the size of the recording sheet  21  in the left-right direction  9 . The control unit  130  may determine the position of the landing limit position P 4  based on the recording sheet  21 . 
     When the recording start position P 3  is upstream of the landing limit position P 4  in the recording direction (e.g., Yes at S 400 ), the frameless recording control may be performed at S 410 . The frameless recording control is described in more detail below. When the recording start position P 3  is downstream of the landing limit position P 4  in the recording direction (e.g., No at S 400 ), the control unit  130  may calculate the distance L 4  (see  FIG. 8B ) between the position where the carriage  28  has stopped and the recording start position P 3 , and may store the distance L 4  in the RAM  133 . The control unit  130  may determine whether the image recording process is in a speed priority mode. The mode of the image recording may be selected between the speed priority mode and a quality priority mode. The selected recording mode may be stored in the EEPROM  134 . 
     When the image recording is set in the speed priority mode (e.g., Yes at S 430 ), the control unit  130  may store a local variable n=30 in the RAM  133 . When the mode of the image recording is not the speed priority mode, i.e., the quality priority mode (e.g., No at S 430 ), the control unit  130  may store a local variable n=60 in the RAM  131   
     The control unit  130  may determine thereafter the distance L 4  is less than n % of the first acceleration distance L 1 . When the distance L 4  is greater than n % of the first acceleration distance L 1  (e.g., No at S 460 ), the control unit  130  may move the carriage  28  and may perform the image recording at S 510 , S 520 , and S 530 . These operations may be similar S 290 , S 300 , and S 310  in  FIG. 7 ; however, since the speed of the carriage  28  does not reach the speed V 1  before reaching the recording start position P 3 , the acceleration recording may be performed from the recording start position P 3 . When the speed of the carriage  28  reaches the speed V 1 , the control unit  130  may stop the acceleration of the carriage  28 . In other words, the mode of the image recording may be switched from the acceleration recording to the constant speed recording. The distance corresponding to n % of the first acceleration distance L 1  may be an example of the second acceleration distance according to the disclosure. The second acceleration distance may be changed when the recording mode is switched, and therefore a speed V 2  (exemplifying the second speed according to the disclosure), which is the minimum speed that the carriage  28  is given when reaching the recording start position P 3 , may be changed. The control unit  130  may perform the acceleration recording when the speed of the carriage  28  at the time when the carriage  28  has reached the recording start position P 3  is between the speed V 2  and the speed V 1 . 
     When the distance L 4  is less than n % of the first acceleration distance L 1  (e.g., Yes at S 460 ), a sufficient acceleration distance required for the current recording mode has not been attained. The control unit  130  again may move the carriage  28  to the target stand-by position P 2  at S 470 . The control unit  130  may confirm that the carriage  28  has stopped (e.g., Yes at S 480 ), after which the control unit  130  again may decide whether the distance L 4 , based on the newly reached position, is less than n % of the first acceleration distance L 1 . When the distance LA is greater than n % of the first acceleration distance L 1  (e.g., No at S 490 ), the control unit  130  may move the carriage  28  to perform the image recording at S 510 , S 520 , and S 530 . When the distance L 4  is less than n % of the first acceleration distance L 1  (e.g., Yes at S 490 ), the control unit  130  may discontinue movement control of the carriage  28 , and may output an error message to be displayed on the LCD panel  47 , or on the display of a computer connected to the multi-function device  10  at S 500 . 
       FIG. 10  is a flowchart showing a control process of the frameless recording. This flowchart corresponds to S 410  in  FIG. 9 . The frameless recording control may be similar to the acceleration recording control according to S 420  to the end in  FIG. 9 , and therefore the description of similar processes will not be repeated. 
     Nevertheless, S 420  to the end in  FIG. 9  and the process of the frameless recording control may be different in the following manner. The distance L 4  between the position where the carriage  28  has stopped and the recording start position P 3  may be calculated at S 420 ; however, at S 600  of the frameless recording control, a distance L 5  (see  FIG. 8C ) between a the position where the carriage  28  has stopped and the landing limit position P 4  may be calculated. At S 460  and S 490 , it may be determined whether the distance L 5  is less than n % of the first acceleration distance L 1 . Similarly, in the frameless recording control, it may be determined whether the image recording is to be performed or the carriage  28  is to be moved again, based on the distance L 5 . The distance L 5  may be used as the reference because, in the frameless recording, the ink ejected before the carriage  28  reaches the landing limit position P 4  does not land on the recording sheet  21 , and thus, may not affect the quality of the image recording. 
     In the image recording control, when the carriage  28  stops at a position upstream of the recording target stand-by position P 2  in the recording direction, the control unit  130  may move the carriage  28  to perform the image from that position without taking an error into account, which may reduce or eliminate the carriage  28  needing to be moved again to the target stand-by position P 2 . In addition, when the carriage  28  starts to move from a position upstream of the target stand-by position P 2  in the recording direction, the carriage  28  may be accelerated to reach the speed V 1  necessary for performing the constant speed recording, before the recording head  29  ejects the ink. 
     In the acceleration recording control, since the speed of the carriage  28  may reach at least 60% or 30% of the speed V 1  before the recording head  29  ejects the ink, the quality of the image recording may be maintained. In addition, the minimum necessary acceleration distance may be determined based upon whether the image recording is performed in the speed priority mode or the quality priority mode. Therefore, a decision may be made as to which of the recording speed or recording quality is more important or desirable. 
     When performing the acceleration recording, the speed of the carriage  28  may not need to reach the speed V 1  necessary for performing the constant speed recording before the carriage  28  reaches the recording start position P 3 ; and therefore, the lower limit of the distance necessary for acceleration may be reduced. Accordingly, it may be even less likely that the carriage  28  needs to be moved again to the target stand-by position P 2 . 
     In the frameless recording, the image recording may be performed without leaving a blank space in the margin of the sheet in the left-right direction  9  because the recording start position P 3  may be located upstream of the landing limit position P 4  in the recording direction. Since the speed of the carriage  28  may reach at least 60% or 30% of the speed V 1  before the carriage  28  reaches the landing limit position P 4 , only the ink ejected thereafter may land on the sheet. Such an arrangement reduces degradation in the quality of the recorded image. 
     In the frameless recording, since it is sufficient that the speed of the carriage  28  reaches at least 60% or 30% of the speed V 1  before the carriage  28  reaches the landing limit position P 4 , not the recording start position P 3 , the lower limit of the distance necessary for acceleration may be reduced. Accordingly, it may be even less likely that the carriage  28  needs to be moved again to the target stand-by position P 2 . 
     Since it may be determined based upon a threshold whether the carriage  28  is to be moved again to the target stand-by position P 1 , it may be less likely that the ink ejected for flushing lands outside of the ink collection tray  49 . 
     Further, since an error message may be displayed when the carriage  28  fails again to stop at the designated position, a user may be made aware of the irregularity immediately; and take necessary measures. 
     In the foregoing embodiments, a purging process or a wiping process may be performed, in addition to the flushing, as part of the maintenance work for the recording head  29 . The purging may be an operation of reducing internal pressure in a cap covering the nozzle of the recording head  29 , using a pump to thereby suck out the waste ink from the nozzle. The wiping may be an operation of cleaning a region around the nozzle of the recording head  29  with a wiper. To move the recording head  29  to the position where the purging or wiping may be performed, the same control as in the flushing process may be performed. 
     The variable, n, to be applied to the first acceleration distance L 1 , determined according to the recording mode in the acceleration recording control or the frameless recording control, may be different from the aforementioned values, or may be adjusted in finer increments. Alternatively, the value of n may be fixed for example at  80 , regardless of the recording mode. In this case, the distance corresponding to 80% of the first acceleration distance L 1  may be attained for the recording head  29  to be accelerated, 
     Alternatively, the value of n may be fixed at  100 . In this case, at least the first acceleration distance L 1  may be attained for the recording head  29  to be accelerated. In other words, since the carriage  28  may be accelerated at least to the speed V 1  before reaching the recording start position P 3  (or landing limit position P 4  in the frameless recording control), the constant speed recording may always be performed. Further, when fixing the value of n, the processes of S 430  to S 450  and S 610  to S 630  may be skipped. In other words, the control unit  130  may control the speed of the carriage  28  to constantly exceed the speed V 1  whenever the carriage  28  reaches the recording start position P 3 , thereby solely performing the constant speed recording. Alternatively, the recording device may accept a setting of the mode, whether the mode of exclusively performing the constant speed recording or the mode of performing one of the constant speed recording and the acceleration recording depending on the condition. 
     Further, the carriage  28  may be made to move to the target stand-by position a desired number of times. For example, the error message may be displayed when the carriage  28  fails to stop at the target stand-by position three times. 
     While the invention has been described in connection with various exemplary structures and illustrative embodiments of the invention, it will be understood by those skilled in the art that other variations and modifications of the structures and embodiments described above may be made without departing from the scope of the invention. Other structures and embodiments will be apparent to those skilled in the art from a consideration of the specification or practice of the invention disclosed herein. It is intended that the specification and described examples are considered as merely illustrative and exemplary of embodiments of the invention, with the true scope of the invention being defined by the following claims.