Patent Publication Number: US-8985731-B2

Title: Liquid ejection apparatuses

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority from Japanese Patent Application Nos. 2012-114863 and 2012-114864 filed on May 18, 2012, which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates generally to a liquid ejection apparatus configured to eject liquid. 
     2. Description of Related Art 
     A known liquid ejection apparatus includes a humidifying mechanism configured to humidify an enclosed space, e.g., an ejection area, opposite to nozzles of a head, after the ejection area is covered (e.g., after a capping operation) when the head is not used or not operated. The humidifying maintenance is performed such that the air in the ejection area is discharged from an air discharge opening disposed at an end of the head in its longitudinal direction and the humidified air is supplied to the ejection area from an air supply opening disposed at an opposite end of the head in its longitudinal direction. 
     In the known liquid ejection apparatus, the air discharge opening and the air supply opening are disposed at positions to interpose the head therebetween in the longitudinal direction of the head. Therefore, the humidified air supplied from the air supply opening flows or moves in a relatively long distance in the longitudinal direction of the head and is discharged from the air discharge opening. The humidified air supplies moisture to liquid adjacent to the nozzles sequentially from the nozzles disposed on a side closer to the air supply opening, to the nozzles disposed on a side closer to the air discharge opening. Therefore, the humidity of the humidified air becomes lower as the humidified air further moves toward the air discharge opening. The decrease in the humidity of the humidified air becomes more significant as a moving distance of the humidified air becomes longer. The significant difference with respect to the drying of liquid may occur between the nozzles disposed on the side closer to the air supply opening and the nozzles disposed on the side closer to the air discharge opening. 
     SUMMARY OF THE INVENTION 
     Aspects of the invention relate to a liquid ejection apparatus in which variances in the drying of nozzles may be reduced and liquid consumption may be reduced. 
     According to an embodiment of the invention, a liquid ejection apparatus comprising: a feeding mechanism configured to feed a recording medium in a first direction; a head comprising a nozzle surface in which nozzles are disposed, wherein the head is configured to eject liquid through the nozzles; and a humidifying mechanism comprising: a humidified air generating device configured to generate humidified air; an output portion connected to the humidified air generating device and configured to output the humidified air generated by the humidified air generating device, wherein the output portion comprises a first opening and a second opening, wherein an area of the second opening is greater than an area of the first opening, and the first opening is separated from the second opening in a second direction perpendicular to the first direction; and a receiving portion configured to receive the humidified air output from the output portion, wherein the head is disposed between the output portion and the receiving portion in the first direction. 
     According to another embodiment of the invention, a liquid ejection apparatus comprising: a feeding mechanism configured to feed a recording medium in a first direction; a head comprising a nozzle surface in which nozzles are disposed, wherein the head is configured to eject liquid through the nozzles; and a humidifying mechanism comprising: a humidified air generating device configured to generate humidified air; an output portion connected to the humidified air generating device and configured to output the humidified air generated by the humidified air generating device, wherein the output portion comprises an opening facing a direction toward a portion of the feeding mechanism and inclined toward the nozzle surface of the head; and a receiving portion is configured to receive the humidified air output from the output portion, wherein the head is disposed between the output portion and the receiving portion in the first direction. 
     According to still another embodiment of the invention, a liquid ejection apparatus comprising: a feeding mechanism configured to feed a recording medium in a first direction; a head comprising a nozzle surface in which nozzles are disposed, wherein the head is configured to eject liquid through the nozzles; and a humidifying mechanism comprising: a humidified air generating device configured to generate humidified air, an output portion connected to the humidified air generating device and disposed at an upstream side surface of the head in the feeding direction, wherein the output portion is configured to output humidified air generated by the humidified air generating device; and a receiving portion disposed at a downstream side surface of the head in the feeding direction, wherein the receiving portion is configured to receive humidified air output from the output portion. 
     According to yet another embodiment of the invention, a liquid ejection apparatus comprising: a feeding mechanism configured to feed a recording medium in a first direction; a head comprising a nozzle surface in which nozzles are disposed, wherein the head is configured to eject liquid through the nozzles; and a humidifying mechanism comprising: a humidified air generating device configured to generate humidified air; an output portion connected to the humidified air generating device and configured to output the humidified air generated by the humidified air generating device through a plurality of openings, such that each of the plurality of openings supplies a same flow amount of the humidified air, and a receiving portion configured to receive the humidified air output from the output portion, wherein the head is disposed between the output portion and the receiving portion. 
     According to still yet another embodiment of the invention, a liquid ejection apparatus comprising: a feeding mechanism configured to feed a recording medium in a first direction; a head comprising a nozzle surface in which nozzles are disposed, wherein the head is configured to eject liquid through the nozzles; a capping mechanism comprising a cover configured to cover a portion of the nozzle surface, such that an enclosed space is formed between the cover and the nozzle surface when the cover covers the portion of the nozzle surface; a humidifying mechanism comprising: a humidified air generating device configured to generate humidified air; an output portion disposed upstream from the head in the first direction, connected to the humidified air generating device and configured to output the humidified air generated by the humidified air generating device; and a receiving portion disposed downstream from the head in the first direction and configured to receive the humidified air output from the output portion, wherein the cover is configured to cover the output portion and the receiving portion when the cover covers the portion of the nozzle surface; and a controller configured to control the humidifying mechanism such that the humidifying mechanism performs a humidifying operation when the nozzle surface is not covered by the cover and the nozzles eject liquid and when the nozzle surface is covered by the cover. 
     Other objects, features, and advantages will be apparent to persons of ordinary skill in the art from the following detailed description of the invention and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present invention, needs satisfied thereby, and the objects, features, and advantages thereof, reference now is made to the following description taken in connection with the accompanying drawings. 
         FIG. 1  is a side view showing an internal structure of an inkjet printer according to an embodiment of the invention. 
         FIG. 2A  is a top view of an inkjet head according to an embodiment of the invention. 
         FIG. 2B  is a bottom view of the inkjet head of  FIG. 2A  according to an embodiment of the invention. 
         FIG. 3A  is an enlarged view of an area  111   a  in  FIG. 2A  according to an embodiment of the invention. 
         FIG. 3B  is a cross-sectional view of the inkjet head taken along a line IIIb-IIIb of  FIG. 3A  according to an embodiment of the invention. 
         FIG. 3C  is a partially enlarged view of a portion of the inkjet head of  FIG. 3B  according to an embodiment of the invention. 
         FIG. 4A  is a drawing depicting a capping mechanism and a humidifying mechanism of an ink jet printer according to an embodiment of the invention. 
         FIG. 4B  is another drawing depicting the capping mechanism and the humidifying mechanism of  FIG. 4A . 
         FIG. 5A  is a cross-sectional view of the inkjet head taken along a line Va-Va of  FIG. 2A  according to an embodiment of the invention. 
         FIG. 5B  is a cross-sectional view of the inkjet head taken along a line Vb-Vb of  FIG. 2A  according to an embodiment of the invention. 
         FIG. 6A  is a drawing depicting a side cover and a capping mechanism according to another embodiment of the invention. 
         FIG. 6B  is a cross-sectional view of the side cover and the capping mechanism taken along a line VI-VI of  FIG. 6A . 
         FIG. 7  is a cross-sectional view of the side cover and the capping mechanism taken along a line VII-VII of  FIG. 6A . 
         FIG. 8  is a cross-sectional view of a side cover according to another embodiment of the invention. 
         FIG. 9A  is a drawing depicting a side cover according to still another embodiment of the invention. 
         FIG. 9B  is a cross-sectional view of the side cover taken along a line IX-IX of  FIG. 9A . 
         FIG. 10A  is a cross-sectional view of an inkjet head during a humidifying operation while an image recording operation is performed according to an embodiment of the invention. 
         FIG. 10B  is a cross-sectional view of an inkjet head during a humidifying operation is performed while an image recording operation is not performed according to an embodiment of the invention. 
         FIG. 11  is a drawing depicting a positional relationship between a sheet accommodated in a sheet supply tray and a nozzle surface of an inkjet head according to an embodiment of the invention. 
         FIG. 12A  is a top view of an inkjet head according to an embodiment of the invention. 
         FIG. 12B  is a bottom view of the inkjet head of  FIG. 12A . 
         FIG. 13A  is a cross-sectional view of the inkjet head taken along a line VIa-VIa of  FIG. 12A . 
         FIG. 13B  is an enlarged view of an area enclosed by a dotted line in  FIG. 13A . 
         FIG. 13C  is a cross-sectional view of the inkjet head taken along a line VIc-VIc of  FIG. 12A . 
         FIG. 14A  is a drawing depicting a side cover and a cap mechanism according to another embodiment of the invention. 
         FIG. 14B  is a cross-sectional view of the side cover and the cap mechanism taken along a line VII-VII of  FIG. 14A . 
         FIG. 15A  is a cross-sectional view of a side cover according to still another embodiment of the invention. 
         FIG. 15B  is a cross-sectional view of the side cover taken along a line X-X of  FIG. 15A . 
         FIG. 16  is a block diagram of a general structure of a control device in  FIG. 1 . 
     
    
    
     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. 
     As depicted in  FIG. 1 , a liquid ejection apparatus, e.g., a printer  101 , may comprise a casing  101   a  having a rectangular parallelepiped shape. A sheet discharge portion  31  may be provided on a top plate of the casing  101   a . An inner space of the casing  101   a  may be divided into spaces A, B, and C in order from an upper side thereof. A sheet feeding path extending from a sheet supply portion  101   c  to the sheet discharge portion  31  may be disposed in the spaces A and B. A recording medium, e.g., sheets P, may be fed in a feeding direction, e.g., first direction, as depicted by black arrows in  FIG. 1 . An image recording process may be performed onto the sheet P in the space A and the sheet P may be fed to the sheet discharge portion  31 . In the space B, the sheet may be supplied to the sheet feeding path. Liquid, e.g., ink, may be supplied from the space C to an inkjet head  1  (hereinafter simply referred to as the “head  1 ”) that may be disposed in the space A. 
     The head  1  configured to eject ink, e.g., black ink, a feeding mechanism  8 , a capping mechanism  40 , a sheet sensor  32 , a humidifying mechanism  50 , as depicted in  FIG. 4 , used for a humidifying operation, and a control device  100  may be disposed in the space A. 
     As depicted in  FIGS. 2A and 2B , the head  1  may have a rectangular parallelepiped shape elongated in a main scanning direction, e.g., a second direction or a longitudinal direction of the head  1 . The main scanning direction may be a direction parallel to a horizontal direction and perpendicular to a sub-scanning direction. The sub-scanning direction may be a direction parallel to a feeding direction D, as indicated by an arrow in  FIG. 1 , in which the sheet P may be fed by feeding roller pairs  24  and  25 . The head  1  may be supported by the casing  101   a , via a head holder  13 , to face an opposing member, e.g., a platen  6 , with a predetermined distance between the head  1  and the platen  6 . The head  1  may be a stacked body comprising a head body  3 , as depicted in  FIGS. 2A and 2B , a reservoir unit, a flexible printed circuits board (FPC), and a circuit board. Ink may be supplied from a cartridge  4  to the reservoir unit. 
     The head body  3  may comprise a flow path unit  9  and an actuator unit  21 . Ink in the reservoir unit may be supplied through an ink supply port  105   b  disposed on an upper surface of the flow path unit  9 . A lower surface of the flow path unit  9  may comprise a nozzle surface  1   a  having nozzles  108 . Ink may be ejected from the nozzles  108  as the actuator unit  21  is driven. 
     The circuit board may be configured to convert signals received from the control device  100  and to output the signals to the FPC. The signals output from the circuit board may be converted into a driving signal by a driver IC of the FPC and may be output to the actuator unit  21  of the head body  3 . As the driving signal is supplied to the actuator unit  21 , the actuator unit  21  may deform to apply pressure to the ink in the flow path unit  9 . 
     The head  1  and a dividing member  41  of the capping mechanism  40  may be mounted to the head holder  13 . The dividing member  41  may be provided to the head  1 . The dividing member  41  may have an annular shape elongated in the main scanning direction, e.g., a longitudinal direction of the dividing member  41 . The dividing member  41  may enclose the head  1 . 
     The feeding mechanism  8  may comprise guide portions  5   a  and  5   b  configured to guide the sheet P and the platen  6 . The feeding mechanism  8  may constitute the sheet feeding path. The guide portion  5   a  and the guide portion  5   b  may be disposed upstream and downstream of the platen  6 , respectively, and the platen  6  may be disposed therebetween in the feeding direction. The guide portion  5   a  may comprise three guides  18   a  and three feeding roller pairs  22 - 24 . The guide portion  5   a  may connect the sheet supply portion  101   c  and the platen  6 . The sheet P for image recording may be fed to the platen  6 . The guide portion  5   b  may comprise three guides  18   b  and four feeding roller pairs  25 - 28 . The guide portion  5   b  may connect the platen  6  and the sheet discharge portion  31 . The sheet P having an image recorded thereon may be fed to the sheet discharge portion  31 . 
     The platen  6  may be configured to support the sheet P from underneath when the sheet P is being fed and an image is recorded on the sheet P. The platen  6  may be a flat plate having a rectangular shape. The platen  6  may be slightly larger than the dividing member  41  in plan view. 
     The sheet sensor  32  may be disposed upstream of the feed roller pair  24 . The sheet sensor  32  may be configured to detect a leading end of the sheet P being fed. A detection signal output from the sensor  32  may be used for synchronizing the operations of the head  1  and the feeding mechanism  8  to record an image at a desired resolution and speed. 
     The humidifying mechanism  50  may be configured to supply humidified air to the nozzles  108 , which may selectively be capped and uncapped. The humidifying mechanism  50  may comprise a humidified air generating portion, e.g., a humidified air generating device, a humidified air supplying portion, e.g., output portion, and a humidified air discharging portion, e.g., receiving portion. The humidified air generating portion may be configured to generate humidified air and supply the humidified air to the humidified air supplying portion. In response to the supply of the humidified air, the humidified air supplying portion may be configured to humidify the nozzles  108 . The humidified air discharging portion may be configured to discharge the air from a portion near the nozzles  108 . As depicted in  FIGS. 4A and 4B , the humidified air generating portion may comprise tubes  53  and  54 , a tank  57 , and a pump  58 . As depicted in  FIGS. 2A and 2B , the humidified air supplying portion may comprise a supply pipe  60 . The humidified air discharging portion may comprise a discharge pipe  80 . The tank  57  may be a source for generating humidified air. When a humidifying operation is performed, the pump  58  may be driven to supply the humidified air from the supply pipe  60 , via the tubes  53  and  54 , to a portion near the nozzles  108 . The air may be discharged from the discharge pipe  80  via the tube. 
     As depicted in  FIGS. 2B ,  4 A and  4 B, the humidifying mechanism  50  may comprise a supply opening portion  65  and a discharge opening portion  85 . The supply opening portion  65  and the discharge opening portion  85  may communicate with an ejection area S 1  which may be a space defined between the nozzle surface  1   a  and the platen  6 . The nozzles  108  may be disposed between the supply opening portion  65  and the discharge opening portion  85  in the sub-scanning direction, e.g., a lateral direction of the head  1  parallel to a shorter side of the head  1 , when viewed in a direction perpendicular to the nozzle surface  1   a . The supply opening portion  65  may extend in the longitudinal direction of the head  1  along an upstream side surface  1 S 1  of the head body  3  in the feeding direction D. The discharge opening portion  85  may extend in the longitudinal direction of the head  1  along a downstream side surface  1 S 2  of the head body  3  in the feeding direction D. The humidifying mechanism  50  may be configured to supply the humidified air to the supply opening portion  65  and discharge the air in a space, e.g., an ejection space S 1 , to the discharge opening portion  85 . 
     Referring back to  FIG. 1 , the sheet supply portion  101   c  may be disposed in the space B. The sheet supply portion  101   c  may comprise a sheet supply tray  35  and a pickup roller  36 . The sheet supply tray  35  may be configured to be removably inserted into the casing  101   a . The sheet supply tray  35  may be configured to hold a stack of the sheets P. The pickup roller  36  may be configured to pick up and feed the uppermost sheet P in the sheet supply tray  35 . 
     The sheet supply tray  35  may comprise a slidable guide that may be slidably attached thereto. The slidable guide may allow a plurality of types of the sheets P with various dimensions in the main scanning direction to be loaded on the sheet supply tray  35 . The guide may comprise a pair of sheet regulating walls  35   a , as depicted in  FIG. 11 , parallel to the feeding direction D of the sheets P. As a user slidably moves one of the sheet regulating walls  35   a  in the main scanning direction, the other one of the sheet regulating walls  35   a  may move in an opposite direction by the same amount, in response to the movement of the one sheet regulating wall  35   a . The center of a space between the sheet regulating walls  35   a  in the main scanning direction may correspond to the center of the head  1 , e.g., the nozzle surface  1   a , in the main scanning direction, e.g., a straight line L passing through the center point Q, as depicted in  FIG. 11 , regardless of where the sheet regulating walls  35   a  may be positioned. In other words, as a user slidably moves the sheet regulating walls  35   a , the center of any types of the sheets P in the main scanning direction may be placed in the same position with respect to the head  1 , as depicted in  FIG. 11 . The sheets P may be fed in the feeding direction D in a center-registration method in which the center of the sheet P in the main scanning direction may correspond to the center of the head  1  in the main scanning direction. 
     In another embodiment, the sheet supply tray  35  may not comprise the slidable guide but comprise a fixed guide. The fixed guide may comprise a pair of sheet regulating walls that may be fixed to each of a plurality of sheet supply trays. In the sheet supply trays, the distance between the sheet regulating walls in the main scanning direction may be different from each other and the center between the sheet regulating walls may correspond to the center of the head  1  in the main scanning direction. 
     The cartridge  4  configured to store, e.g., black, ink may be disposed in the space C and may be removably mounted to the casing  101   a . The cartridge  4  may be connected to the head  1 , via a tube and a pump. The pump may be driven to forcibly send ink to the head  1 , e.g., when a purging operation is performed or ink is initially introduced to the head  1 . At other times, the pump may be stopped and may not prevent the ink supply to the head  1 . 
     As depicted in  FIG. 16 , the control device  100  may comprise: a central processing unit (CPU)  400 ; a read only memory (ROM)  401  rewritably storing programs to be executed by the CPU and data used for these programs; and a random access memory (RAM)  402  for temporarily storing the data in the execution of the programs. The control device  100  may comprise various functional sections which are constituted by cooperation of these hardware and software in the ROM  401  with each other. The control device  100  may be configured to control an image recording operation and a maintenance operation. In the image recording operation, the control device  100  may drive the sheet supply portion  101   c , the guide portions  5   a  and  5   b  of the feeding mechanism  8  and the head  1 , based on a recording instruction, e.g., an image data, received from an external apparatus, e.g., a personal computer connected to the printer  101 . More specifically, the sheet P may be fed from the sheet supply tray  35  to a recording area opposite the head  1 . In the recording area, the head  1  may be driven in synchronization with the detection signal from the sheet sensor  32 . When the sheet P passes directly below the head  1 , ink may be ejected onto the sheet P to form a desired image. The sheet P may further be fed in the feeding direction D to the sheet discharge portion  31  disposed on the upper portion of the casing  101   a.    
     In the maintenance operation, an ink discharge operation, e.g., a purging operation and a flushing operation, a capping operation, and a humidifying operation may be performed regularly or in response to user&#39;s requests, to maintain or recover ink ejection performance of the head  1 . 
     For example in the ink discharge operation, viscous ink may be discharged from the nozzles  108 . The purging operation may be performed to forcibly eject ink from the head  1  by applying a pressure to ink with the pump, without driving the actuator unit  21 . After the ink is forcibly discharged, the nozzle surface  1   a  may be wiped to clean the nozzle surface  1   a . The flushing operation may be performed to eject a predetermined amount of ink from the head  1  by driving the actuator unit  21 , based on flushing data that may be different from image data. 
     The capping operation may be performed when the head  1  is not operated. As depicted in  FIG. 4A , the dividing member  41  may divide or enclose the ejection area S 1  from an external space S 2 . The nozzles  108  may communicate only with the divided or enclosed ejection space S 1 . Thus, a path for the moisture to dissipate from the nozzles  108  may be closed. Thus, increase in the viscosity of ink and drying may be reduced. 
     The humidifying operation may be performed both when an image recording operation is not performed, e.g., while the capping operation is performed, and when an image recording operation is performed. When performing the humidifying operation while an image recording operation is not performed, the humidified air may be supplied to the enclosed ejection space S 1 , as depicted in  FIG. 4A , via the supply opening portion  65 . The air in the ejection space S 1  may be discharged, via the discharge opening portion  85 . As the humidified air is supplied to the ejection space S 1 , the ejection space S 1  may be filled with vapor. Therefore, drying of the nozzles  108  may be reduced. During a non-operation of the head  1 , the humidifying operation may be performed for a predetermined period of time while the capping operation is performed. When performing the humidifying operation while an image recording operation is performed, the humidified air may be supplied from the supply opening portion  65  to the ejection space S 1  that may be open to the external space S 2 , as depicted in  FIG. 4B . The air in the ejection space S 1  may be discharged from the discharge opening portion  85 . As the humidified air is supplied to the ejection space S 1 , the humidified air may be supplied to the nozzles  108 . Therefore, drying of the nozzles  108  may be reduced. 
     As depicted in  FIG. 2A , the head body  3  may comprise a laminated body comprising the flow path unit  9  and four actuator units  21  fixed on an upper surface  9   a  of the flow path unit  9 . The upper surface  9   a  may have openings of pressure chambers  110 , as depicted in  FIG. 3A , that may be arranged in matrix. The pressure chambers  110  and the nozzles  108  may be provided below the actuator units  21 . As depicted in  FIG. 3C , each actuator unit  21  may seal the openings of the pressure chambers  110  and define an upper wall of the pressure chambers  110 . 
     As depicted in  FIG. 3B , the flow path unit  9  may comprise a laminated body comprising nine sheets of stainless plates  122 - 130  that are laminated. The flow path unit  9  may have an ink flow path formed therein. As depicted in  FIGS. 2A ,  3 A, and  3 B, the ink flow path may have a manifold flow path  105  that has the ink supply port  105   b  formed on the upper surface  9   a  as an end of the manifold flow path  105  and branches to a sub-manifold flow path  105   a , and an individual ink flow path leading from an outlet of the sub-manifold flow path  105   a  to the nozzle  108  formed on the lower surface of the flow path unit  9 , through the pressure chamber  110 . As depicted in  FIG. 2B , the nozzles  108  may be arranged in matrix in correspondence with the respective pressure chambers  110  on the nozzle surface  1   a . The nozzles  108  may be arranged corresponding to a resolution in the main scanning direction, e.g., 600 dpi. 
     As depicted in  FIG. 2A , each of four actuator units  21  may have a trapezoidal shape in plan view. The actuator units  21  may be provided in a staggered manner in the main scanning direction to avoid ink supply ports  105   b.    
     The actuator unit  21  may comprise a lead zirconate titanate (PZT)-base ceramic material having ferroelectricity. As depicted in  FIG. 3C , the actuator unit  21  may comprise three piezoelectric layers  141 - 143 . The uppermost piezoelectric layer  141  may comprise individual electrodes  135  formed on an upper surface thereof. The piezoelectric layer  141  may be polarized in its thickness direction. The piezoelectric layer  142  may comprise a common electrode  134  formed on all of an upper surface thereof. Portions disposed between the individual electrodes  135  and the pressure chambers  110  may act as individual unimorph-type actuators. When an electric field in a polarized direction occurs in portions between the individual electrodes  135  and the common electrodes  134 , the portion acting as the actuators may deform toward the pressure chambers  110 , e.g., unimorph deformation. At this time, pressure may be applied to ink in the pressure chambers  110  to eject ink droplets from the nozzles  108 . The common electrodes  134  may maintain a ground potential. A driving signal may be selectively supplied to the individual electrodes  135 . 
     A fill-before-fire method may be used to eject ink. The individual electrodes  135  may be kept at a predetermined potential. The actuator may make unimorph deformation. As the driving signal is supplied to the individual electrodes  135 , the individual electrodes  135  may be temporarily kept at the same potential as that of the common electrode  134 . After the elapse of predetermined time, the potential of the individual electrodes  135  may return to the predetermined potential. At a time when the individual electrodes  135  becomes the same potential as that of the common electrode  134 , the unimorph deformation of the actuators may be released, and ink may be drawn into the pressure chambers  110 . At a time when the potential of the individual electrodes  135  returns to the predetermined potential, the actuators may make the unimorph deformation again to eject ink droplets from the nozzles  108 . 
     As depicted in  FIGS. 2A ,  2 B,  5 A and  5 B, a side cover  70  may be provided on an outer periphery of the head body  3 . The side cover  70  may be configured to surround the outer circumference of the head body  3 . The side cover  70  may comprise an annular member comprising resin. The side cover  70  may be fixed on side surfaces of the flow path unit  9  and the reservoir unit. The side cover  70  may comprise a pair of longer sections  71  extending in the main scanning direction and a pair of shorter sections  72  extending in the sub-scanning direction. The shorter sections  72  may connect the longer sections  71 . 
     A pair of the longer sections  71  may have an inlet and an outlet for the humidified air. The inlet may be disposed in an upper portion of the longer section  71  in  FIG. 2A  on the upstream side in the feeding direction D. The humidified air may enter the ejection space S 1  from the inlet. The inlet may have a through hole  71   a  formed through the upstream-side longer section  71  in a vertical direction, e.g., a direction perpendicular to the nozzle surface  1   a , and the supply pipe  60  may be inserted into the through hole  71   a . The outlet may be disposed in a lower portion of the longer section  71  in  FIG. 2A  on the downstream side in the feeding direction D. Air in the ejection space S 1  may be discharged from the outlet. The outlet may have a through hole  71   b  formed through the downstream-side longer section  71  in the vertical direction and the discharge pipe  80  may be inserted into the through hole  71   b . The through holes  71   a  and  71   b  may be symmetrically disposed with respect to the center point Q on the nozzle surface  1   a.    
     The head holder  13  may comprise a rigid frame comprising a metal. The head holder  13  may be configured to support the perimeters of side surfaces of the head body  3 . The dividing member  41  of the capping mechanism  40  may be attached to the head holder  13 . 
     A contact portion between the head holder  13  and the head body  3  may be sealed with sealant on the perimeters of the contact portion. A contact portion between the head holder  13  and the dividing member  41  may be fixed by adhesive on the perimeters of the contact portion. The head holder  13  may have through holes  13   a  and  13   b  in correspondence with the through holes  71   a  and  71   b , respectively. The supply pipe  60  and the discharge pipe  80  may be inserted into the through holes  13   a  and  13   b , respectively. 
     The capping mechanism  40  may comprise the dividing member  41 , a lip movement mechanism, e.g., a cap movement mechanism  48 , configured to move the dividing member  41  up and down, and the platen  6 . The dividing member  41  may be configured to enclose the side cover  70  and the ejection space S 1 , e.g., the nozzles  108 , together with the platen  6  and the nozzle surface  1   a . The dividing member  41  may be elongated in the main scanning direction. As depicted in  FIGS. 5A and 5B , the dividing member  41  may comprise a lip member  42 , a movable member  43 , and a diaphragm  44 . 
     The lip member  42  may comprise an annular-shaped elastic member, e.g., rubber, and may surround the head  1  in plan view. That is, the lip member  42  may be disposed outside the side cover  70 . The lip member  42  may comprise a base portion  42   x , and a protruding portion  42   a  protruding from a lower surface of the base portion  42   x . The protruding portion  42   a  may have a triangular cross section. An end of the protruding portion  42   a  may be configured to contact the platen  6 . The movable member  43  may be fixed to an upper surface of the base portion  42   x . The movable member  43  may comprise an annular-shaped rigid material, e.g., stainless steel. 
     The diaphragm  44  may comprise an annular flexible thin-film material, e.g., rubber, and may surround the head  1  in plan view. An outer periphery of the diaphragm  44  may be connected to the lip member  42 . The diaphragm  44  may comprise a contact portion  44   a  on an inner periphery thereof. Inner side surfaces of the contact portion  44   a  may be fixed to outer side surfaces of the side cover  70 . An upper surface of the contact portion  44   a  may be fixed to a lower surface of the head holder  13 . 
     The cap movement mechanism  48  may comprise gears  45 , and a motor. The gears  45  may be connected to the movable member  43 . When the motor is driven under the control of the control device  100 , the gears  45  may rotate to move the movable member  43  up and down. Accordingly, the base portion  42   x  may move up and down. Thus, the position of an end of the protruding portion  42   a  may change in the vertical direction relative to the nozzle surface  1   a.    
     An end of the lip member  42 , e.g., the protruding portion  42   a , may move between a contact position to contact a surface  6   a  of the platen  6 , as depicted in  FIG. 4A , and a separation position to separate from the surface  6   a , as depicted in  FIGS. 4B-5B , in association with the movement of the movable member  43 . When the lip member  42  contacts the surface  6   a , the dividing member  41 , the nozzle surface  1   a  and the platen  6  may divide or enclose the ejection space S 1  from the external space S 2 . Thus, the platen  6  may function as a part of the capping mechanism  40 . When the lip member  42  is in the separation position, the ejection space S 1  may be open to the external space S 2 . In the separation position, an end of the lip member  42  may be positioned slightly lower than the nozzle surface  1   a , so as not to prevent the feeding of the sheets P. 
     As described above, the humidifying mechanism  50  may comprise the humidified air supplying portion, e.g., the supply pipe  60 , the humidified air discharging portion, e.g., the discharge pipe  80 , the humidified air generating portion, e.g., the tubes  53  and  54  or discharging tube and supplying tube, the tank  57  and the pump  58 . 
     The supply pipe  60  may correspond to the inlet for the humidified air. As depicted in  FIGS. 5A and 5B , the supply pipe  60  may comprise a first supply pipe  61  and a supplying member, e.g., a second supply pipe  63 , that may communicate with each other. After the humidified air flows into the first supply pipe  61 , the air may be supplied to the ejection space S 1 , via the second supply pipe  63 . The first and second supply pipes  61  and  63  may be symmetrically disposed with respect to the center point Q on the nozzle surface  1   a.    
     The first supply pipe  61  may extend in the vertical direction along the upstream-side side surface  1 S 1  of the head  1 . The first supply pipe  61  may be inserted into the through hole  71   a  of the upstream-side longer section  71  and the through hole  13   a  of the head holder  13 . The tube  54  may be connected to an exposed end portion of the first supply pipe  61 . A gap or a space may be disposed between the first supply pipe  61  and each through hole  13   a ,  71   a . The gap may be filled with a sealing material. 
     As depicted in  FIG. 5B , an upper portion of the second supply pipe  63  may be bonded to a lower surface of the upstream-side longer section  71 . The second supply pipe  63  may be disposed between the lip member  42  and the upstream-side side surface  1 S 1  of the head  1 . As depicted in  FIG. 5A , the second supply pipe  63  may extend in the main scanning direction. An end of the second supply pipe  63  may be connected to the first supply pipe  61 . The opposite end of the second supply pipe  63  may be closed. 
     A lower surface of the second supply pipe  63  may be provided with the supply opening portion  65  extending along the upstream-side side surface  1 S 1  of the head  1 . The supply opening portion  65  may have supply openings, e.g., openings, of supply holes  65   a , formed on the second supply pipe  63 . The supply holes  65   a  may be arranged in the main scanning direction and may communicate with an interior of the second supply pipe  63 . The supply opening portion  65  may constitute a part of a humidified air supply passage. The humidified air may be uniformly supplied to the ejection space S 1  through each supply hole  65   a.    
     As depicted in  FIG. 2B , the two outermost supply holes  65   a  with respect to the main scanning direction may be disposed outside the respective two outermost nozzles  108  on the nozzle surface  1   a . In other words, the supply opening portion  65  may have a length longer than the distance between the two outermost nozzles  108 . Therefore, the humidified air may be supplied to all nozzles  108 , and variances in the supply of the humidified air to all nozzles  108  may be reduced. The second supply pipe  63  may be disposed at a position higher than the nozzle surface  1   a , so that the second supply pipe  63  may not prevent the feeding of the sheets P. 
     As depicted in  FIG. 5B , the supply holes  65   a  may be formed on a lower portion of the second supply pipe  63  on a side closer to the head  1 . The opening of each supply hole  65   a  may oppose the ejection space S 1 . Thus, the humidified air supplied from the supply holes  65   a  may be effectively flow in the downstream side in the feeding direction D. Accordingly, drying of the nozzles  108  may further be reduced. 
     The resistance of a passage of the second supply pipe  63  per unit length to the air may become lower toward the downstream side in a flowing direction of the humidified air in the second supply pipe  63 , e.g., a rightward direction in  FIG. 5A . As depicted in  FIG. 2B , areas of openings of the supply holes  65   a  may become greater as the supply holes  65   a  are disposed on the more downstream side, e.g., a downward direction in  FIG. 2B . The supply holes  65   a  may be disposed further from the upstream side, e.g., an upward direction in  FIG. 2B , toward the downstream side, in the flowing direction of the humidified air. Therefore, approximately a uniform amount of the humidified air may flow from each supply hole  65   a . In another embodiment, a cross-sectional area of the passage of the second supply pipe  63  may be increased from the upstream side toward the downstream-side in the flowing direction of the humidified air. 
     The discharge pipe  80  may correspond to the outlet for the humidified air. The discharge pipe  80  may comprise a first discharge pipe  81  and a discharging member, e.g., a second discharge pipe  83 , that may communicate with each other. After the air in the ejection space S 1  flows into the second discharge pipe  83 , the air may be discharged to the humidified air generating portion, via the first discharge pipe  81 . The first and second discharge pipes  81  and  83  may be structured, similar to the first and second supply pipes  61  and  63 , respectively. The first and second discharge pipes  81  and  83  may be symmetrically disposed with respect to the center point Q on the nozzle surface  1   a.    
     The first discharge pipe  81  may extend in the vertical direction along the downstream-side side surface  1 S 2  of the head  1 . The first discharge pipe  81  may be inserted into the through holes  71   b  and  13   b . The tube  53  may be connected to an exposed end portion of the first discharge pipe  81 . An upper portion of the second discharge pipe  83  may be bonded to a lower surface of the downstream-side longer section  71 . The second discharge pipe  83  may be disposed between the lip member  42  and the downstream-side side surface  1 S 2  of the head  1 . The second discharge pipe  83  may extend in the main scanning direction. An end of the second discharge pipe  83  may be connected to the first discharge pipe  81 . The opposite end of the second discharge pipe  83  may be closed. 
     A lower surface of the second discharge pipe  83  may be provided with the discharge opening portion  85  extending along the downstream-side side surface  1 S 2 . The discharge opening portion  85  may have discharge openings, e.g., openings, of discharge holes  85   a , formed on the second discharge pipe  83 . The discharge holes  85   a  may be arranged in the main scanning direction and may communicate with an interior of the second discharge pipe  83 . The discharge opening portion  85  may be a part of a humidified air discharge passage. The air in the ejection space S 1  may be discharged from each discharge hole  85   a.    
     As depicted in  FIG. 2B , the two outermost discharge holes  85   a  with respect to the main scanning direction may be disposed outside the respective two outermost nozzles  108  on the nozzle surface  1   a . The discharge opening portion  85  may have a length longer than the distance between the two outermost nozzles  108 . Therefore, the humidified air supplied from the supply opening portion  65  may easily flow in a direction parallel to the sub-scanning direction, e.g., the feeding direction D. Variances in the supply of the humidified air to all nozzles  108  may be reduced. The second discharge pipe  83  may be disposed at a position higher than the nozzle surface  1   a , so that the second discharge pipe  83  may not prevent the feeding of the sheets P. 
     As depicted in  FIG. 5B , the discharge holes  85   a  may be formed on a lower portion of the second discharge pipe  83  on a side closer to the head  1 . The opening of each discharge hole  85   a  may oppose the ejection space S 1 . Thus, the air in the ejection space S 1  may be readily discharged. 
     The resistance of a passage of the second discharge pipe  83  per unit length to the air may become greater toward the downstream side in a flowing direction of the humidified air in the second discharge pipe  83 , e.g., a downward direction in  FIG. 2B ). Areas of openings of the discharge holes  85   a  may become smaller as the discharge holes  85   a  are disposed on the more downstream side, e.g., a downward direction in  FIG. 2B ). The discharge holes  85   a  may be disposed further from the upstream side, e.g., an upward direction in  FIG. 2B , toward the downstream side, in the flowing direction of the humidified air. Therefore, approximately a uniform amount of the humidified air may flow into each discharge hole  85   a . In another embodiment, a cross-sectional area of the passage of the second discharge pipe  83  may be reduced from the upstream side toward the downstream-side in the flowing direction of the humidified air. 
     The tubes  53  and  54 , the tank  57 , the supply pipe  60 , and the discharge pipe  80  may constitute a circulation passage for the humidified air. As depicted in  FIGS. 4A and 4B , an end of the tube  53  may be connected to the discharge pipe  80  and an opposite end of the tube  53  may be connected to the tank  57 . The pump  58  may be disposed between the tube  53  and the tank  57 . An end of the tube  54  may be connected to the tank  57  and an opposite end of the tube  54  may be connected to the supply pipe  60 . 
     The tank  57  may be configured to store humidifying liquid in its lower portion and the air humidified by the humidifying liquid in its upper portion. The tube  53  may be in fluid communication with the lower portion of the tank  57  storing the humidifying liquid. The tube  54  may be in fluid communication with the upper portion of the tank  57 . A check valve may be attached to a portion of the tube  53  near the tank  57  to prevent or reduce backflow of the humidifying liquid in the tank  57 . When the humidifying liquid in the tank  57  is reduced, the liquid may be replenished to the tank  57  from a replenishment tank. 
     The printer  101  may perform the capping operation and the humidifying operation while an image recording operation is not performed. 
     When the capping operation is performed, the lip member  42  may be placed in the contact position, as depicted in  FIG. 4A , under the control of the control device  100 . The dividing member  41  may divide or enclose the ejection space S 1  from the external space S 2 . Consequently, a path for the humidified air may be formed in the lateral direction of the head  1 , e.g., the sub-scanning direction, in the dividing member  41 . 
     Ink adjacent to the nozzles  108  may become dry if the ejection space S 1  is continuously divided or enclosed by the capping operation. When the printer  101  is used for a long period of time, an inner wall of the dividing member  41  may be contaminated with ink mist or ink itself. Residual ink in the dividing member  41  that has been dried may function as a desiccant that may absorb humidity and moisture. Therefore, the residual ink in the dividing member  41  may promote drying of ink adjacent to the nozzles  108  in the enclosed ejection space S 1 . 
     The nozzles  108  may be positioned between the supply opening portion  65  and the discharge opening portion  85  with respect to the lateral direction of the head  1 . When the head  1  is not operated and the ejection space S 1  is divided from the external space S 2 , the humidified air may be supplied to the ejection space S 1  to humidify the nozzles  108 . 
     When the humidifying operation is performed when the ejection space S 1  is enclosed, e.g., while an image recording operation is not performed, the pump  58  may be driven under the control of the control device  100 . As depicted in  FIG. 4A , the air may flow in a direction indicated by outline arrows. The humidified air in the upper portion of the tank  57  may be supplied to the second supply pipe  63 , via the tube  54  and the first supply pipe  61 . The humidified air may be supplied to the ejection space S 1  from the supply holes  65   a  of the supply opening portion  65 . While the air in the ejection space S 1  is replaced with the humidified air, the air may flow in the sub-scanning direction toward the discharge opening portion  85 . The air in the ejection space S 1  may be suctioned by the pump  58  through the first discharge pipe  81 , to flow from the discharge opening portion  85  to the tank  57 . The air may be humidified in the lower portion of the tank  57  and may move to the upper portion of the tank  57 . The generated humidified air may be supplied to the ejection space S 1  while the pump  58  is being driven. 
     When the uncapping operation is performed, the lip member  42  may be placed in the separation position as depicted in  FIGS. 4B-5B , under the control of the control device  100 . The dividing member  41  may open the ejection space S 1  to the external space S 2 . 
     The printer  101  may perform an image recording operation, based on a received recording instruction. The humidifying operation may be performed while an image recording operation is performed, under the control of the control device  100 . The pump  58  may be driven under the control of the control device  100 . As depicted in  FIG. 4B , the air may flow in a direction indicated by the outline arrows, similar to the humidifying operation that may be performed when the ejection space S 1  is enclosed while an image recording operation is not performed. The humidified air in the upper portion of the tank  57  may be supplied to the second supply pipe  63 , via the tube  54  and the first supply pipe  61 . The humidified air may be supplied to the ejection space S 1  and to the nozzles  108  from the supply holes  65   a  of the supply opening portion  65 . 
     The humidified air may be moved from the supply holes  65   a  to the nozzles  108  by the air current associated with the feeding of the sheet P. At this time, the air in the ejection space S 1  may be forcibly suctioned by the pump  58  to move from the discharge opening portion  85  to the tank  57 . The air in the ejection space S 1  may be discharged outside, e.g., to the tank  57 , from the discharge opening portion  85  disposed downstream of the head  1  in the feeding direction D. Thus, flow of the humidified air may be formed from the supply opening portion  65  to the discharge opening portion  85 . Even when the air current associated with the feeding of the sheet P is not present near the nozzle surface  1   a , e.g., before the sheet P passes the nozzle surface  1   a  or after the elapse of some time after the sheet P has passed the nozzle surface  1   a , the humidified air may be supplied to the nozzles  108  because the air in the ejection space S 1  may be forcibly suctioned by the pump  58  and flow from the supply opening portion  65  to the discharge opening portion  85 . Consequently, even when the head  1  is uncapped, e.g., the ejection space S 1  is open, drying of the nozzles  108  may be reduced. Therefore, an amount of ink consumed by the flushing operation may be reduced. The air suctioned from the discharge opening portion  85  may be humidified in the lower portion of the tank  57  and may move to an upper portion of the tank  57 , similar to the humidifying operation that may be performed when the ejection space S 1  is enclosed while an image recording operation is not performed. The generated humidified air may be supplied to the ejection space S 1  while the pump  58  is being driven. When the head  1  is uncapped, part of the humidified air output from the supply holes  65   a  is likely not to flow to the discharge opening portion  85  because of turbulence. So, the control device  100  may control the pump  58  such that flow amount of the humidified air output from the supply holes  65   a  per unit time when the head  1  is uncapped is greater than flow amount of the humidified air output from the supply holes  65   a  per unit time when the head  1  is capped so that flow amount of the humidified air from the ejection space S 1  to the discharge opening portion  85  per unit time when the head  1  is uncapped become the same as flow amount of the humidified air from the ejection space S 1  to the discharge opening portion  85  per unit time when the head  1  is capped. 
     The opening areas of the supply holes  65   a  may increase toward a downstream side in the flowing direction of the humidified air. The resistance of the passage of the second supply pipe  63  per unit length to the air may decrease toward the downstream side in the flowing direction of the humidified air in the second supply pipe  63 . Therefore, approximately a uniform amount of the humidified air may flow from each supply hole  65   a . In the ejection space S 1 , the air current may flow in the feeding direction D. As the supply opening portion  65  is disposed along the upstream-side side surface  1 S 1  of the head  1 , the humidified air may be effectively supplied to the nozzles  108 . 
     An end of the lip member  42  may be placed at a position slightly lower than the nozzle surface  1   a  in the separation position. Thus, the humidified air supplied to the ejection space S 1  may stay in the ejection space S 1 . Therefore, the humidified air may be effectively supplied to the nozzles  108 , and drying of the nozzles  108  may further be reduced. 
     The humidifying operation may be performed both when an image recording operation is performed and when the image recording operation is not performed and the ejection space S 1  is divided or enclosed by the capping operation. In the humidifying operation, the humidified air supplied from the supply opening portion  65  may flow in the feeding direction D e.g., the lateral direction of the head  1 . In other words, the humidified air may flow toward the discharge opening portion  85  through the ejection space S 1 . Because the supply opening portion  65  and the discharge opening portion  85  extend in the longitudinal direction of the head  1 , the humidified air may be supplied to the nozzles  108 . The head  1  may be disposed between the supply opening portion  65  and the discharge opening portion  85  in the feeding direction D. Therefore, a path for supplying the humidified air may be relatively short. Therefore, variances in the humidity of the humidified air supplied in the feeding direction D may be reduced. Thus, variances in the drying of ink in the nozzles  108  may be reduced while an image recording operation is performed, or is not performed when the ejection space S 1  is closed. 
     When the humidifying operation is performed during an image recording operation, the air current may flow in the feeding direction D in the ejection space S 1 , in association with the feeding of the sheet P. Therefore, the humidified air may be effectively supplied to the nozzles  108 , so that drying of the nozzles  108  may be reduced when the ejection space S 1  is open during an image recording operation. Thus, discharge of ink by the flushing operation, may be reduced. 
     In the humidifying operation, the air in the ejection space S 1  may be forcibly discharged from the discharge opening portion  85 . Therefore, the supplied humidified air may flow in the feeding direction D. Thus, variances in the supply of the humidified air may be reduced. 
     In the air flow passage, the humidified air may circulate between the pump  58  and the ejection space S 1 . A resistance of an air flow passage from the pump  58  to each supply hole  65   a , and a resistance of an air flow passage from each discharge hole  85   a  to the pump  58  may be uniformly set. Thus, variances in the drying of ink in the nozzles  108  may be reduced on the whole. 
     An axis of an opening of each supply hole  65   a  of the supply opening portion  65  and each discharge hole  85   a  of the discharge opening portion  85  may be inclined toward an inner side of the ejection space S 1 . Therefore, the humidified air may be effectively circulated and moisture may be supplied uniformly to the nozzles  108 . 
     The capping mechanism  40  may comprise the dividing member  41 , the cap movement mechanism  48  and the platen  6 , e.g., opposing member. Therefore, the capping mechanism  40  may be relatively smaller in size, and may reduce the size of the printer  101 . 
     As depicted in  FIGS. 12B and 13B , in another embodiment, a distance between the adjacent two supply openings, e.g., openings, of the supply holes  65   a  may become shorter toward a more outer portion of the head  1  from its central portion in the main scanning direction. Therefore, the number of openings of the supply holes  65   a  may be greater in the outer portion of the head  1  than its central portion in the main scanning direction. Therefore, a greater amount of the humidified air may be supplied to an outer portion of the ejection space S 1  than its central portion in the main scanning direction. 
     A distance between the adjacent two discharge openings, e.g., openings, of the discharge holes  85   a  may become shorter toward a more outer portion of the head  1  than its central portion in the main scanning direction. Therefore, the number of openings of the discharge holes  85   a  may be greater in the outer portion of the head  1  than its central portion in the main scanning direction. Therefore, a greater amount of the air may be discharged from an outer portion of the ejection space S 1  than its central portion in the main scanning direction. 
     The printer  101  may perform an image recording operation, as described above, based on a received recording instruction. In this embodiment, the sheet P may be fed in the center-registration method. In the center-registration method, the sheet P may be placed on the sheet supply tray  35  such that the center of the sheet P in the main scanning direction may correspond to the center of the nozzle surface  1   a , e.g., the line L passing the center point Q, in the main scanning direction. In a recording area, the sheet P may be fed such that the center of the sheet P in the main scanning direction may align with the center of a distribution area of the nozzles  108  in the main scanning direction. If the size of the sheet P is smaller than the distribution area of the nozzles  108 , the nozzles  108  disposed on each end in the main scanning direction may be exposed to the atmosphere. The drying of the nozzles  108  may occur while an image recording operation is performed. 
     When an image recording operation is performed, the humidifying operation may be performed under the control of the control device  100 . In this embodiment, more supply holes  65   a  of the supply opening portion  65  may be disposed on a more outer portion of the head  1  than its central portion in the main scanning direction. 
     When the humidifying operation is performed while an image recording operation is performed, the pump  58  may be driven under the control of the control device  100 . As depicted in  FIG. 4B , the air may flow in a direction indicated by the outline arrows, similar to the humidifying operation that may be performed when the ejection space S 1  is enclosed while an image recording operation is not performed, as described above. The humidified air in the upper portion of the tank  57  may be supplied to the second supply pipe  63  via the tube  54  and the first supply pipe  61 . The humidified air may be supplied to the ejection space S 1  and to the nozzles  108  from the supply holes  65   a  of the supply opening portion  65 . 
     The humidified air may be moved from the supply holes  65   a  to the nozzles  108  by the air current associated with the feeding of the sheet P. At the downstream of the head  1  in the feeding direction D, the air in the ejection space S 1  may be forcibly suctioned by the pump  58 , to move from the discharge opening portion  85  to the tank  57 . Thus, flow of the humidified air may be formed from the supply opening portion  65  to the discharge opening portion  85 . Even when the air current associated with the feeding of the sheet P does not flow near the nozzle surface  1   a , e.g., before the sheet P passes the nozzle surface  1   a  and after the elapse of some time after the sheet P has passed the nozzle surface  1   a , the humidified air may be supplied to the nozzles  108  because the air in the ejection space S 1  may be forcibly suctioned by the pump  58  and flow from the supply opening portion  65  to the discharge opening portion  85 . Consequently, even when the head  1  is uncapped, e.g., the ejection space S 1  is open, drying of the nozzles  108  may be reduced. Therefore, an amount of ink consumed by the flushing operation, may be reduced. 
     Opening areas of the supply holes  65   a  may become greater toward a more downstream side in the flowing direction of the humidified air. The resistance of the passage of the second supply pipe  63  per unit length to the air may decrease toward the downstream side in the flowing direction of the humidified air in the second supply pipe  63 . Therefore, approximately a uniform amount of the humidified air may flow from each supply hole  65   a . Further, the number of the supply holes  65   a  may be greater in the outer portion of the head  1  than its central portion in the main scanning direction. Therefore, a greater amount of the humidified air may be supplied to an outer portion of the ejection space S 1  than its central portion in the main scanning direction. The nozzles  108  disposed outward at each end portion of the head  1  in the main scanning direction may be less frequently used and may be readily dried in the feeding of the sheets P with the center-registration method. Drying of the nozzles  108  may be effectively reduced as a greater amount of the humidified air may be supplied to an outer portion of the ejection space S 1 . Therefore, an amount of ink consumed by the flushing operation may be reduced. The air suctioned from the discharge opening portion  85  may be humidified in the lower portion of the tank  57  and may move to the upper portion of the tank  57 , similar to the humidifying operation that may be performed when the ejection space S 1  is closed while an image recording operation is not performed, as described above. The generated humidified air may be supplied to the ejection space S 1  while the pump  58  is driven. 
     An end of the lip member  42  may be placed at a position slightly lower than the nozzle surface  1   a  in the separation position. Thus, the humidified air supplied from the supply holes  65   a  of the supply opening portion  65  to the ejection space S 1  may readily stay in the ejection space S 1 . Therefore, the humidified air may be effectively supplied to the nozzles  108 , and drying of the nozzles  108  may further be reduced. 
     The humidifying operation may be performed while an image recording operation is performed. In the humidifying operation, the humidified air supplied from the supply opening portion  65  may flow toward the discharge opening portion  85  across the ejection space S 1  by riding the air current associated with the feeding of the sheet P. Thus, drying of the nozzles  108  may be reduced when the ejection space S 1  is open during an image recording operation. Further, a greater amount of the humidified air may be supplied to an outer portion of the ejection space S 1  than its central portion in the main scanning direction. Therefore, drying of the less-frequently used nozzles  108 , which may be disposed outward, e.g., on each end portion of the nozzle surface  1   a  in the main scanning direction, may be effectively reduced. Consequently, discharge of ink by the flushing operation may be reduced. 
     The humidifying operation may also be performed when the ejection space S 1  is divided or enclosed by the capping operation while an image recording operation is not performed. Therefore, when the ejection space S 1  is divided from the external space S 2 , drying of ink in the nozzles  108  may be reduced. 
     In the humidifying operation, the air in the ejection space S 1  may be discharged from the discharge opening portion  85 . Therefore, the humidified air supplied from the supply opening portion  65  may readily flow in the feeding direction D, e.g., the lateral direction of the head  1 . In other words, the air may flow toward the discharge opening portion  85  through the ejection space S 1 . Consequently, drying of ink in the nozzles  108  may be effectively reduced. 
     As described above, the capping mechanism  40  may comprise the dividing member  41 , the cap movement mechanism  48 , and the platen  6 . Therefore, the capping mechanism  40  may be relatively smaller in size, and may reduce the size of the printer  101 . An axis of the opening of each supply hole  65   a  of the supply opening portion  65  and each discharge holes  85   a  of the discharge opening portion  85  may incline toward the inner side of the ejection space S 1 . Such structure may contribute to an effective circulation of the humidified air in the ejection space S 1  and a uniform moisture supply to the nozzles  108 . 
     Referring to  FIGS. 6A-7 , in still another embodiment, a humidifying mechanism  250  may comprise the humidified air supplying portion and the humidified air discharging portion that may defined by a side cover  270  and the dividing member  41 . The side cover  270  may be configured to surround the outer circumference of the head  1 . The side cover  270  may comprise an annular member comprising resin. The side cover  270  may comprise a pair of longer sections  271  extending in the main scanning direction and a pair of shorter sections  272  extending in the sub-scanning direction. The longer sections  271  may have the same length as the side surfaces  1 S 1  and  1 S 2  of the head  1  in the main scanning direction. The shorter sections  272  may connect the longer sections  271 . 
     The upstream-side longer section  271  in the feeding direction D may comprise an upstream-side fixed portion  273   a  and an upstream-side flange  274   a  in the feeding direction D. The upstream-side fixed portion  273   a  may extend in the main scanning direction, and may be fixed to the side surface  1 S 1  of the head  1 . The contact portion  44   a  may be fixed to an outer side surface of the upstream-side fixed portion  273   a . The upstream-side flange  274   a  may be integrally formed with the upstream-side fixed portion  273   a . The upstream-side flange  274   a  may protrude from a lower end of the upstream-side fixed portion  273   a  toward the upstream side in the feeding direction D. The upstream-side flange  274   a  may extend in the main scanning direction. 
     The upstream-side flange  274   a  may have recesses  275   a  formed at an end thereof, e.g., an upstream end in the feeding direction D. The recesses  275   a  may pass through the upstream-side flange  274   a  in the vertical direction. The recesses  275   a  may define, together with the lip member  42 , supply openings, e.g., openings  265   a , and guide paths  256   b  connected to the openings  265   a . The openings  265   a  defined by the recesses  275   a  and the lip member  42  may correspond to a supply opening portion  265 . The openings  265   a  of the recesses  275   a  may be disposed equidistantly in the main scanning direction. The two outermost openings  265   a  of the recesses  275   a  may be disposed outside the respective two outermost nozzles  108  on the nozzle surface  1   a . The supply opening portion  265  may have a length longer than the distance between the two outermost nozzles  108 . Therefore, effects similar to those of the aforementioned embodiments may be obtained. The lower surface of the side cover  270  may be disposed at a position higher than the nozzle surface  1   a , so that the side cover  270  may not prevent the feeding of the sheet P. 
     The upstream-side fixed portion  273   a  may comprise a protruding portion  276   a  protruding upward. The protruding portion  276   a  may be disposed on a central portion of an upper surface of the upstream-side fixed portion  273   a  in the main scanning direction. The upstream-side fixed portion  273   a  may have a flow path  277   a  extending in the vertical direction from a central portion of the upstream-side fixed portion  273   a  in the main scanning direction. The flow path  277   a  may pass through a central portion of the protruding portion  276   a  to communicate with an opening  278   a  formed on a side surface of the upstream-side fixed portion  273   a . The protruding portion  276   a  may be inserted into the through hole  13   a  of the head holder  13  and connected to the tube  54 . A gap or a space may be disposed between the protruding portion  276   a  and the through hole  13   a . The gap may be filled with a sealing material. The humidified air may flow through the opening  278   a , via the tube  54 . An end of the upstream-side flange  274   a  may contact an inner peripheral surface of the lip member  42 . The shorter section  272  may contact the diaphragm  44  on each end thereof in the sub-scanning direction. An area enclosed by the upstream-side longer section  271  and the dividing member  41  may be enclosed at each end in the main scanning direction to form a flow path  279   a  connected to the flow path  277   a . As depicted in  FIGS. 6A and 6B , the humidified air may flow from the opening  278   a  in the flow path  279   a  in the right and left directions in  FIGS. 6A and 6B  and be supplied to the ejection space S 1  from the recesses  275   a . The recesses  275   a , e.g., the openings  265   a  and the guide paths  265   b , and the flow paths  277   a  and  279   a  may constitute a humidified air supply passage through which the humidified air may be supplied to the ejection space S 1 . 
     As depicted in  FIGS. 6A and 6B , areas of the openings  265   a  of the recesses  275   a  may be become greater as the openings  265   a  toward a more downstream side, e.g., outward sides in  FIGS. 6A and 6B , in the flowing direction of the humidified air, e.g., as the openings  265   a  are disposed further from the upstream side, e.g., a middle portion in  FIGS. 6A and 6B  toward the downstream side, in the flowing direction of the humidified air. Therefore, approximately a uniform amount of the humidified air may flow from each opening  265   a  of the recesses  275   a.    
     The downstream-side longer section  271  in the feeding direction D may comprise a downstream-side fixed portion  273   b  and a downstream-side flange  274   b . The downstream-side longer section  271  and the upstream-side longer section  271  may be symmetrically disposed with respect a straight line that extends in the main scanning direction and passes through the center point Q on the nozzle surface  1   a . The downstream-side fixed portion  273   b  may be fixed to the side surface  1 S 2  of the head  1 . The contact portion  44   a  may be fixed to an outer side surface of the downstream-side fixed portion  273   b . The downstream-side flange  274   b  may protrude from a lower end of the downstream-side fixed portion  273   b  toward the downstream side in the feeding direction D. 
     The downstream-side flange  274   b  may have recesses  275   b  formed at an end thereof, e.g., a downstream end in the feeding direction D. The recesses  275   b  may pass through the downstream-side flange  274   b  in the vertical direction. The recesses  275   b  may define, together with the lip member  42 , discharge openings, e.g., openings  285   a , and guide paths  285   b  connected to the openings  285   a . The openings  285   a  defined by the recesses  275   b  and the lip member  42  may correspond to a discharge opening portion  285 . The openings  285   a  of the recesses  275   b  may be disposed equidistantly in the main scanning direction. The two outermost openings  285   a  of the recesses  275   b  may be disposed outside the respective two outermost nozzles  108  on the nozzle surface  1   a . In other words, the discharge opening portion  285  may have a length longer than the distance between the two outermost nozzles  108 . Therefore, effects similar to those of the first embodiment may be obtained. 
     The downstream-side fixed portion  273   b  may comprise a protruding portion  276   b  protruding upward. The protruding portion  276   b  may be disposed on a central portion of an upper surface of the downstream-side fixed portion  273   b  in the main scanning direction. The downstream-side fixed portion  273   b  may have a flow path  277   b  extending in the vertical direction from a central portion of the downstream-side fixed portion  273   b  in the main scanning direction. The flow path  277   b  may pass through a central portion of the protruding portion  276   b  to communicate with an opening  278   b  formed on a side surface of the downstream-side fixed portion  273   b . The protruding portion  276   b  may be inserted into the through hole  13   b  of the head holder  13  and connected to the tube  53 . A gap or a space may be disposed between protruding portion  276   b  and the through hole  13   b . The gap may be filled with a sealing material. An end of downstream-side flange  274   b  may contact an inner peripheral surface of the lip member  42 . The shorter section  272  may contact the diaphragm  44  on each end thereof in the sub-scanning direction. An end of an area enclosed by the downstream-side longer section  271  and the dividing member  41  in the main scanning direction may be closed to form a flow path  279   b  connected to the flow path  277   b . As depicted by arrows in  FIG. 7 , the air in the ejection space S 1  may be discharged from the recesses  275   b , e.g., the openings  285   a . In the flow path  279   b , the air suctioned from the recesses  275   b , via the openings  285   a  and the guide paths  285   b , may flow in the central portion of the flow path  279   b  toward the opening  278   b , and discharged to the tank  57 , e.g., outside, via the tube  53 . The recesses  275   b , e.g., the openings  285   a  and the guide paths  285   b  and the flow paths  277   b  and  279   b  may correspond to a humidified air discharge passage through which air in the ejection space S 1  may be discharged outside. 
     Areas of the openings  285   a  of the recesses  275   b  may become smaller toward a more downstream side, e.g., a middle portion in  FIG. 6B , in a flowing direction of the humidified air, e.g., as the openings  285   a  are disposed further from the upstream side, e.g., right and left directions in  FIG. 6B , toward the downstream side, in the flowing direction of the humidified air. Therefore, approximately a uniform amount of the humidified air may flow from each recess  275   b.    
     The printer  101  comprising the humidifying mechanism  250  may perform the humidifying operation when the ejection space S 1  is enclosed while an image recording operation is or is not performed. The humidified air may be supplied to the ejection space S 1  from the recesses  275   a . In the humidifying operation that may be performed while an image recording operation is performed, the lip member  42  may be positioned in the separation position. In the separation position, an end of the lip member  42  may be positioned slightly lower than the flanges  274   a  and  274   b . Therefore, the humidified air released from the recesses  275   a  may contact the inner surface of the lip member  42  and may readily stay near the recesses  275   a . The humidified air may flow effectively in the feeding direction D with the air current associated with the feeding of the sheet P and suctioning from the discharge opening portion  285 . Thus, drying of the nozzles  108  may further be reduced. Consequently, even when the head  1  is uncapped, e.g., the ejection space S 1  is open, drying of the nozzles  108  may be reduced. Therefore, an amount of ink consumed by the flushing operation may be reduced. 
     In the humidifying operation that may be performed when the ejection space S 1  is enclosed while an image recording operation is not performed, the humidified air may be supplied to the ejection space S 1  from the recesses  275   a . e.g., the supply opening portion  265 , similar to the first embodiment. While the air in the ejection space S 1  is replaced with the humidified air, the air may flow in the sub-scanning direction toward the discharge opening portion  85 . The air in the ejection space S 1  may be suctioned by the pump  58 , and may flow from the discharge opening portion  285  to the tank  57 . The air may be humidified in the lower portion of the tank  57  and may move to the upper portion of the tank  57 . The generated humidified air may be supplied to the ejection space S 1  while the pump  58  is being driven. 
     As described above, the humidified air supplied from the supply opening portion  265  may flow in the feeding direction D, e.g., the lateral direction of the head  1 , in the humidifying operation, similar to the first embodiment. Therefore, variances in the supply of the humidified air to nozzles  108  may be reduced. Further, because a path for supplying the humidified air is relatively short, variances in the humidity of the humidified air supplied from the supply opening portion  265  to each of the nozzles  108  may be reduced. Thus, variance in the drying of ink in the nozzles  108  may be reduced while an image recording operation is performed, or is not performed when the ejection space S 1  is enclosed. The supply opening portion  265  and the discharge opening portion  285  may comprise the recesses  275   a  and  275   b , respectively and may be simply structured. Effects similar to those of the aforementioned embodiments may be obtained, with respect to the similar structures. 
     In yet another embodiment, each flange  274   a  and  274   b  may have a plurality of through holes  295   a  and  295   b , instead of the recesses  275   a  and  275   b , respectively, as depicted in  FIG. 8 . The through holes  295   a  and  295   b  may be disposed closer to the head  1  than the recesses  275   a ,  275   b . The through holes  295   a ,  295   b  may have opening areas or shapes structured similar to those of the recesses  275   a  and  275   b , respectively. Therefore, effects similar to the second embodiment may be obtained. The openings of the through holes  295   a  and  295   b  may correspond to the supply opening portion and the discharge opening portion, respectively. 
     An axis of an opening of each through hole  295   a  and  295   b  may be inclined toward an inner side of the ejection space S 1 . Therefore, the humidified air may be effectively circulated, and moisture may be supplied uniformly to the nozzles  108 . 
     Another embodiment of the invention, as shown in  FIGS. 14A and 14B , the opposing inner side surfaces of the guide paths  265   b  in the main scanning direction may incline outward in the longitudinal direction of the head  1  as the guide paths  265   b  extend downward. Thus, the humidified air may be supplied outwardly from the openings  265   a  to the ejection space S 1  in the main scanning direction. Therefore, a greater amount of the humidified air may be supplied to an outer portion of the ejection space S 1  than its central portion. The inner surfaces of the outermost recesses  275   a  in the main scanning direction may be inclined such that the humidified air may be supplied toward a contact portion of the platen  6  to the lip member  42 , e.g., toward an end of the lip member  42  placed in the contact position. Therefore, when the ejection space S 1  is divided or enclosed from the external space S 2 , moisture may be supplied to ink that may be accumulated in the contact portion between the lip member  42  and the platen  6 . 
     The opposing inner side surfaces of the guide paths  285   b  in the main scanning direction may incline outward in the longitudinal direction of the head  1  as the guide paths  285   b  extend downward. 
     The printer  101  comprising the humidifying mechanism  250  may perform the humidifying operation both when an image recording operation is performed and when the image recording operation is not performed and the ejection space S 1  is enclosed. The humidified air may be supplied to the ejection space S 1  from the openings  265   a . When the humidifying operation is performed during an image recording operation, the lip member  42  may be positioned in the separation position. In the separation position, an end of the lip member  42  may be positioned slightly lower than the flanges  274   a  and  274   b . Therefore, the humidified air released from the openings  265   a  may contact the inner surface of the lip member  42  and may readily stay near the openings  265   a . The humidified air may not readily flow toward the upstream side in the feeding direction D. At this time, approximately the same amount of the humidified air may be supplied outward from each opening  265   a  in the main scanning direction. Therefore, a greater amount of the humidified air may stay outward in the main scanning direction. The humidified air may flow effectively in the feeding direction D with the air current associated with the feeding of the sheet P and suctioning from the discharge opening portion  285 . Therefore, a greater amount of the humidified air may be supplied to an outer portion of the ejection space S 1  than its central portion. Therefore, even when the head  1  is uncapped, e.g., the ejection space S 1  is open, drying of the less-frequently used nozzles  108  disposed outward, e.g., on each end portion of the nozzle surface  1   a  in the main scanning direction, may be effectively reduced. Therefore, an amount of ink consumed by the flushing operation may be reduced. 
     When the humidifying operation is performed with the ejection space S 1  be enclosed and an image recording operation is not performed, the humidified air may be supplied to the ejection space S 1  from the openings  265   a  of the supply opening portion  265 . At this time, the humidified air supplied from the outermost openings  265   a  in the main scanning direction may flow to the contact portion of the platen  6  to the lip member  42 . Therefore, when the ejection space S 1  is divided or enclosed from the external space S 2 , moisture may be directly supplied to ink that may be accumulated in the contact portion between the lip member  42  and the platen  6 . Therefore, ink near the nozzles  108  may not be readily dried when the ejection space S 1  is divided or enclosed. While the air in the ejection space S 1  is replaced with the humidified air, the air may flow in the sub-scanning direction toward the discharge opening portion  285 . The air in the ejection space S 1  may be suctioned by the pump  58 , and may flow from the discharge opening portion  285  to the tank  57 . The air may be humidified in the lower portion of the tank  57  and may move to the upper portion of the tank  57 . The generated humidified air may be supplied to the ejection space S 1  while the pump  58  is being driven. 
     A greater amount of the humidified air may be supplied from the supply opening portion  265  to an outer portion of the ejection space S 1  than its central portion in the main scanning direction in the humidifying operation. Therefore, drying of the less-frequently used nozzles  108  disposed outward, e.g., on each end portion of the nozzle surface  1   a  in the main scanning direction, may be effectively reduced. Therefore, discharge of ink by the flushing operation, may be reduced. 
     The supply opening portion  265  and the discharge opening portion  285  may comprise the recesses  275   a  and  275   b , e.g., the openings  265   a  and  285   a  and the guide paths  265   b  and  285   b , respectively. The supply opening portion  265  and the discharge opening portion  285  may be simply structured and formed. Effects similar to those of the aforementioned embodiments may be obtained, with respect to the similar structures. 
     Referring to  FIGS. 9A-10B , in another embodiment, a humidifying mechanism  350  may comprise the humidified air supplying portion and the humidified air discharging portion that may be provided in a side cover  370 . The side cover  370  may be configured to surround the outer circumference of the head  1 . The side cover  370  may comprise an annular member comprising resin. The side cover  370  may comprise a pair of longer sections  371  extending in the main scanning direction and a pair of shorter sections  372  extending in the sub-scanning direction. The longer section  371  may have the same length as the side surfaces  1 S 1 ,  1 S 2  of the head  1  in the main scanning direction. The shorter sections  372  may connect the longer sections  371 . 
     The upstream-side longer section  371  in the feeding direction D may be fixed to the side surface  1 S 1  of the head  1 . The upstream-side longer section  371  may comprise a protruding portion  376   a  protruding upward. The protruding portion  376   a  may be disposed on a central portion of an upper surface of the upstream-side longer section  371  in the main scanning direction. The upstream-side longer section  371  may have a flow path  377   a  extending in the vertical direction from a central portion of the upstream-side longer section  371  in the main scanning direction. The upstream-side longer section  371  may have a flow path  378   a  extending in an interior of the upstream-side longer section  371  in the main scanning direction from a central portion thereof in the vertical direction. The flow path  377   a  may pass through a central portion of the protruding portion  376   a  to communicate with the flow path  378   a . The protruding portion  376   a  may be inserted into the through hole  13   a  of the head holder  13  and connected to the tube  54 . A gap or a space may be disposed between the protruding portion  376   a  and the through hole  13   a . The gap may be filled with a sealing material 
     The upstream-side longer section  371  may have supply slits  375   a  formed on a lower surface thereof. The supply slits  375   a  may communicate with the flow path  378   a . The supply slits  375   a  may define supply openings e.g., openings  365   a , and guide paths  365   b  connected to the opening  365   a . The openings  365   a  of the supply slits  375   a  may constitute a supply opening portion  365 . The humidified air may flow in the flow path  377   a  and  378   a , via the tube  54 . As depicted in  FIGS. 9A and 9B , the humidified air may flow in the flow path  378   a  from the central portion of  FIGS. 9A and 9B  toward the right and left directions in  FIGS. 9A and 9B , and be supplied to the ejection space S 1  from each of the supply slits  375   a . The supply slits  375   a , e.g., the openings  365   a  and the guide paths  365   b , and the flow paths  377   a  and  378   a  may correspond to a humidified air supply passage through which the humidified air may be supplied to the ejection space S 1 . 
     The openings  365   a  of the supply slits  375   a  may be disposed equidistantly in the main scanning direction. The two outermost openings  365   a  of supply slits  375   a  may be disposed outside the respective two outermost nozzles  108  on the nozzle surface  1   a . The supply opening portion  365  may have a length longer than the distance between the two outermost nozzles  108 . Thus, effects similar to those of the aforementioned embodiments may be obtained. The lower surface of the side cover  370  may be disposed at a position higher than the nozzle surface  1   a , so that the side cover  370  may not prevent the feeding of the sheet P. 
     As depicted in  FIG. 10A , the guide paths  365   b  of the supply slits  375   a  may incline toward the head  1 , e.g., toward the downstream side in the feeding direction D, such that the openings  365   a  may oppose the ejection space S 1 . Therefore, the humidified air supplied from the openings  365   a  of the supply slits  375   a  may flow effectively toward the downstream side in the feeding direction. Thus, drying of the nozzles  108  may further be reduced. 
     The resistance of the passage of the flow path  378   a  per unit length to air may become lower toward the downstream side in a flowing direction of the humidified air in the flow path  378   a , e.g., toward the right and left directions from the central portion of  FIGS. 9A and 9B . As depicted in  FIG. 9B , areas of the openings  365   a  of the supply slits  375   a  may become greater as the supply slits  375   a  are disposed on the more downstream-side, e.g., the right and left directions in  FIGS. 9A and 9B . Therefore, approximately the same amount of the humidified air may flow out from each of the supply slits  375   a.    
     The downstream-side longer section  371  and the upstream-side longer section  371  may be symmetrically disposed with respect a straight line that extends in the main scanning direction and passes through the center point Q on the nozzle surface  1   a . The downstream-side longer section  371  may be fixed to the side surface  1 S 2  of the head  1 . The downstream-side longer section  371  may comprise a protruding portion  376   b . The downstream-side longer section  371  may comprise a flow path  377   b  extending in the vertical direction from a central portion of the downstream-side longer section  371  in the main scanning direction and a flow path  378   b  extending in the main scanning direction from a central portion of the downstream-side longer section  371  in the vertical direction. The flow path  378   b  may communicate with the flow path  377   b . The protruding portion  376   a  may be inserted into the through hole  13   b  of the head holder  13  and connected to the tube  53 . A gap or a space may be disposed between the protruding portion  376   b  and the through hole  13   b . The gap may be filled with a sealing material. 
     The downstream-side longer section  371  may have discharge slits  375   b  formed on a lower surface thereof. The discharge slits  375   b  may communicate with the flow path  378   b . The discharge slits  375   b  may define discharge openings, e.g., openings  385   a , and guide paths  385   b  connected to the openings  385   a . The openings  385   a  of the discharge slits  375   b  may constitute a discharge opening portion  385 . The discharge slits  375   b  may be arranged in the main scanning direction. The air in the ejection space S 1  may be discharged from each of the discharge slits  375   b . The discharge slits  375   b , e.g., the openings  385   a  and the guide paths  385   b , and the flow paths  377   b  and  378   b  may correspond to a humidified air discharge passage through which air in the ejection space S 1  may be discharged outside. 
     As depicted in  FIG. 9B , the two outermost openings  385   a  of the discharge slits  375   b  with respect to the main scanning direction may be disposed outside the respective two outermost nozzles  108  on the nozzle surface  1   a . The discharge opening portion  385  may have a length longer than the distance between the two outermost nozzles  108 . Therefore, the humidified air supplied from the supply opening portion  365  may easily flow in a direction parallel to the sub-scanning direction, e.g., the feeding direction D. Variances in the supply of the humidified air to all nozzles  108  may be reduced. 
     As depicted in  FIG. 10A , the guide paths  385   b  of the discharge slits  375   b  may incline toward the head  1 , e.g., toward the upstream side in the feeding direction D, such that the openings  385   b  may oppose the ejection space S 1 . Therefore, the air in the ejection space S 1  may be readily discharged. 
     The resistance of the passage of the flow path  378   b  per unit length to air may become greater toward the downstream side in a flowing direction of the humidified air in the flow path  378   b , e.g., from the right and left directions toward the central portion of  FIG. 9B . Areas of the openings  385   a  of the discharge slits  375   b  may become smaller toward a more downstream-side, e.g., the central portion in  FIG. 9B . Therefore, approximately the same amount of the air may flow in from each of the discharge slits  375   b.    
     As depicted in  FIG. 10B , a capping mechanism  340  may comprise a dividing member  341 , an opposing member  345 , and a movement mechanism configured to move the opposing member  345 . The opposing member  345  may be a flat plate having a rectangular shape in plan view. An outer size of the opposing member  345  may be approximately the same as the size of the side cover  370 . The dividing member  341  may comprise an annular-shaped elastic material, e.g., rubber. The dividing member  341  may integrally formed with the opposing member  345  and protrude from peripheral ends of the opposing member  345 . 
     The movement mechanism may be configured to move the opposing member  345  under the control of the control device  100 , e.g., controller. An end of the dividing member  341  may change in the vertical direction relative to the side cover  370 . The dividing member  341  may selectively move between a contact position, as depicted in  FIG. 10B , where the end of the dividing member  341  may contact a peripheral end of the lower surface of the side cover  370 , and a separation position where the end of the dividing member  341  may separate from the side cover  370 , in association with the movement of the opposing member  345 . When the dividing member  341  contacts the side cover  370 , the dividing member  341 , the opposing member  345 , and the nozzle surface  1   a  may divide or enclose the ejection space S 1  from the external space S 2 . When the dividing member  341  separates from the side cover  370 , the ejection space S 1  may be open to the external space S 2 . 
     The printer  101  comprising humidifying mechanism  350  and the capping mechanism  340  may perform the humidifying operation both when an image recording operation is performed and when an image recording operation is not performed and the ejection space S 1  is enclosed. 
     When the capping operation is performed, the dividing member  341  may be placed in the contact position, as depicted in  FIG. 10B , under the control of the control device  100 . The ejection space S 1  may be divided or enclosed from the external space S 2 . Consequently, a path for the humidified air may be formed in the lateral direction of the head  1 , e.g., the sub-scanning direction, in the dividing member  341 . 
     When the humidifying operation is performed and the ejection space S 1  is closed, e.g., when an image recording operation is not performed, the humidified air may be supplied to the ejection space S 1  from the openings  365   a  of the supply opening portion  365  under the control of the control device  100 . While the air in the ejection space S 1  is replaced with the humidified air, the air may flow in the sub-scanning direction toward the openings  385   a  of the discharge opening portion  385 . The air in the ejection space S 1  may be suctioned by the pump  58 , and may flow from the discharge opening portion  385  to the tank  57 . The air may be humidified in the lower portion of the tank  57  and may move to the upper portion of the tank  57 . The generated humidified air may be supplied to the ejection space S 1  while the pump  58  is being driven. 
     When the uncapping operation is performed, the dividing member  341  may be placed in the separation position under the control of the control device  100 . As depicted in  FIG. 10A , the dividing member  341  may open the ejection space S 1  to the external space S 2 . 
     When the humidifying operation is performed while an image recording operation is performed, the air may flow, similar to the humidifying operation that may be performed when the ejection space S 1  is enclosed while an image recording operation is not performed. The humidified air may be supplied from the openings  365   a  of the supply slits  375   a  of the supply opening portion  365  to the ejection space S 1  and to the nozzles  108 . The humidified air may move from the openings  365   a  of the supply slits  375   a  to the nozzles  108 . Therefore, even when the head  1  is uncapped, e.g., the ejection space S 1  is open, drying of the nozzles  108  may be reduced. Therefore, an amount of ink consumed by the flushing operation may be reduced. 
     As described above, the humidified air supplied from the supply opening portion  365  may flow in the feeding direction D, e.g., the lateral direction of the head  1 , in the humidifying operation. Therefore, variances in the supply of the humidified air to nozzles  108  may be reduced, similar to the first and second embodiments. Further, because a path for supplying the humidified air is relatively short, variances in the humidity of the humidified air supplied from the supply opening portion  365  to each of the nozzles  108  may be reduced. Thus, variances in the drying of ink in the nozzles  108  may be reduced both when an image recording operation is performed and when an image recording operation is not performed and the ejection space S 1  is closed. 
     Referring to  FIGS. 15A and 15B , in another embodiment of the invention, the opposing inner side surfaces of the guide paths  365   b  in the main scanning direction may incline outward in the longitudinal direction of the head  1  as the guide paths  365   b  extend downward. 
     Therefore, the humidified air may be supplied from the openings  365   a  outwardly to the ejection space S 1  in the main scanning direction. Therefore, a greater amount of the humidified air may be supplied to an outer portion of the ejection space S 1  than its central portion. 
     The opposing inner side surfaces of the guide paths  385   b  in the main scanning direction may incline outward in the longitudinal direction of the head  1  as the guide paths  385   b  extend downward. 
     Approximately the same amount of the humidified air may be supplied outward in the main scanning direction from each opening  365   a . Therefore, a greater amount of the humidified air may be supplied to an outer portion of the ejection space S 1  than its central portion in the main scanning direction. Therefore, drying of the less-frequently used nozzles  108  that may be disposed outward, e.g., on each end portion of the nozzle surface  1   a  in the main scanning direction, may be effectively reduced. Consequently, an amount of ink consumed by the flushing operation may be reduced. 
     The humidifying operation may be performed while an image recording operation is performed. In the humidifying operation that may be performed while an image recording operation is performed, the humidified air supplied from the supply opening portion  365  may flow in the feeding direction D, e.g., the lateral direction of the head  1 , in association with the feeding of the sheet P. The humidified air may flow thorough the ejection space S 1  to the discharge opening portion  85 . Therefore, during the image recording operation when the ejection space S 1  is open, drying of the nozzles  108  may be reduced. A greater amount of the humidified air may be supplied from the supply opening portion  365  to an outer portion of the ejection space S 1  than its central portion in the main scanning direction. Therefore, drying of the less-frequently used nozzles  108  that may be disposed outward, e.g., on each end portion of the nozzle surface  1   a  in the main scanning direction, may be reduced. Consequently, discharge of ink by the flushing operation may be reduced. 
     While the disclosure has been described in detail with reference to the specific embodiment thereof, this is merely an example, and various changes, arrangements and modifications may be applied therein without departing from the spirit and scope of the disclosure. 
     The first supply pipe  61  may be connected to a central portion of the second supply pipe  63 , and the first discharge pipe  81  may be connected to a central portion of the second discharge pipe  83 . In another embodiment, the protruding portion  276   a  and  276   b , and  376   a  and  376   b  may be connected to an end of the upper surface of the longer section  271  and  371 , respectively. 
     The air in the ejection space S 1  may be forcibly suctioned from the discharge opening portion  85 ,  285 , and  385 . The air in the ejection space S 1  may be naturally discharged from the discharge opening portion  85 ,  285 , and  385  that may be directly connected or communicate to the outside, e.g., the external space S 2 . The supply opening portion  65 ,  265 , and  365  and the discharge opening portion  85 ,  285 , and  385  may have a length shorter than the distance between the two outermost nozzles  108  in the main scanning direction. The supply opening portion  65 ,  265 , and  365  and the discharge opening portion  85 ,  285 , and  385  may comprise one opening extending in the main scanning direction. In the above embodiments, the humidifying operation may be performed while an image recording operation is performed. Alternatively, the humidifying operation may be performed when an image recording operation is not performed, as long as the ejection space S 1  is open to the external space S 2 . More specifically, the humidifying operation may be performed, e.g., during a waiting time until an image recording operation is performed after the divided or enclosed ejection space S 1  becomes open to the external space S 2  or a waiting time until the ejection space S 1  is divided or enclosed after an image recording operation is finished. 
     In the above embodiments, the passage of the humidified air may be provided separately from the head body  3 . Alternatively, the passage of the humidified air may be provided in the head body  3  separately from the ink flow path in the head body  3 . For example, the passage for the humidified air, e.g., the supply opening portion  365  and the discharge opening portion  385 , may open or be provided in the side cover  370 , e.g., the longer section  371 , in the third embodiment. Alternatively, the passage for the humidified air may open or be provided on a periphery of the nozzle surface  1   a . Supply and discharge openings for the humidified air may interpose all nozzles  108  on the nozzle surface  1   a  therebetween in the sub-scanning direction. In this case, the number of components may be reduced and a structure of the printer  101  may be simplified. Consequently, the size of the printer  101  may be reduced. The supply opening and discharge opening portions may be disposed closer to the nozzles  108 . This structure may contribute to efficient supply of the humidified air. 
     The pump  58  may be disposed in a return portion of the circulation passage of the humidified air with respect to the tank  57 . Supply of the humidified air to the ejection space S 1  may be performed by the force of the pump  58  suctioning the air from the ejection space S 1 . Alternatively, the pump  58  may be disposed in an outward portion of the circulation passage of the humidified air with respect to the tank  57 . Supply of the humidified air to the ejection space S 1  may be performed by the force of the pump  58  sending the humidified air to the ejection space S 1 . 
     The invention may be applied to a line-type and serial type liquid ejection apparatus. The invention may be applied not only printers but also, for example, facsimile machines and copiers. Further, the invention may be applied to liquid ejection apparatus configured to perform recording by ejecting liquid other than ink. The recording mediums may not be limited to the sheets P but may be various types of recordable mediums. The invention may be applied regardless of the liquid ejection method. For example, the piezoelectric element may be used as a method to eject liquid in the embodiments. Alternatively, resistance heating or capacitance may be used. 
     Other 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 the described examples are considered merely as exemplary of the invention, with the true scope of the invention being defined by the following claims.