Abstract:
According to the present invention, firstly, since the cleaning liquid is deposited onto the nozzle surface by the nozzle surface cleaning liquid deposition device, then it is possible to raise the dissolving effect, which is a chemical effect of dissolving adhering material which is adhering to the nozzle surface. Consequently, it is possible to remove the adhering material readily by subsequently wiping the nozzle surface with the wiping member, and hence the physical effects can also be improved. Furthermore, since the cleaning liquid is deposited so as to wet the wiping member, then it is possible to suppress the drawing out of liquid from the nozzles due to the absorbing characteristics of the wiping member, and therefore ejection defects due to solidification of drawn out liquid can be prevented. Consequently, it is possible to improve ejection stability of the droplet ejection head.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a nozzle surface cleaning apparatus and an image recording apparatus, and more particularly, to a nozzle surface cleaning apparatus which wipes a nozzle surface by abutting and pressing a traveling wiping member against the nozzle surface, and to an image recording apparatus. 
         [0003]    2. Description of the Related Art 
         [0004]    With use, foreign matter of various types, such as ink residue, paper dust, or the like, adheres to the nozzle surface of an inkjet head which is used in an image recording apparatus, for example, an inkjet recording apparatus. If foreign matter adheres to the nozzle surface, ink droplets ejected from the nozzles are affected, variation occurs in the ejection direction of the ink droplets, it becomes difficult to deposit the ink droplets at the prescribed positions on the recording medium, and this becomes a cause of decline in the image quality. Therefore, in an inkjet recording apparatus, it is important to remove foreign matter periodically by means of a maintenance method, such as wiping, or the like. 
         [0005]    For example, Japanese Patent Application Publication No. 2004-195908 describes controlling a wiping sheet which wipes a droplet ejection head, by a winding motor which forms a conveyance mechanism, and wiping the droplet ejection head with the wiping sheet after supplying cleaning liquid to the wiping sheet by a cleaning liquid ejection head. Furthermore, Japanese Patent Application Publication No. 2010-188707 describes a cleaning apparatus having a cleaning liquid supply device which supplies cleaning liquid by a non-contact method onto a nozzle surface of a droplet ejection head, and a wiping device which wipes a nozzle surface. 
         [0006]    However, the cleaning apparatus which is described in Japanese Patent Application Publication No. 2004-195908 has a short contact time between the cleaning liquid and the adhering material on the ejection surface of the droplet ejection head, and therefore has not been able to display sufficient cleaning effects by the cleaning liquid. Therefore, it has been necessary to use physical force to remove the adhering material, by applying a high pressure to the droplet ejection head or increasing the relative speed differential between the droplet ejection head and the wiping sheet. However, if excessive force is applied to the ejection surface of a droplet ejection head, then there is a problem in that decline in the properties of the lyophobic film formed on the ejection surface becomes greater. 
         [0007]    Moreover, the method of depositing cleaning liquid onto the nozzle surface of the liquid ejection head described in Japanese Patent Application Publication No. 2010-188707 induces ink to be drawn out from the nozzles due to contact with the meniscus in the nozzles, when the nozzle surface is wiped with a wiping member. For instance, if a rubber blade made or silicone, or the like, is used for the wiping member, then drawing out of ink from the nozzles is observed when the relative speed differential becomes large. Moreover, if cloth having fine fibers is used as a wiping member in order to improve the wiping properties, then the drawing out of ink becomes greater due to the absorption characteristics of the wiping member. The ink which is drawn out dries and solidifies, and is pushed inside the nozzle orifices during the next wiping action, thus creating an adverse effect on the directionality of the ejection. 
       SUMMARY OF THE INVENTION 
       [0008]    The present invention was devised in view of circumstances such as these, an object thereof being to provide a nozzle surface cleaning apparatus and an image recording apparatus which sufficiently raises the dissolving effects of the cleaning liquid, as well as suppressing the drawing out of ink onto the nozzle surface after wiping, and which can thereby suppress deterioration of the directionality of ejection. 
         [0009]    In order to achieve the above object, the present invention provides a nozzle surface cleaning apparatus which cleans a nozzle surface of a droplet ejection head, including: a nozzle surface cleaning liquid deposition device which deposits cleaning liquid onto the nozzle surface of the droplet ejection head; a wiping member travel device which causes a wiping member having absorbing characteristics to travel; a wiping member cleaning liquid deposition device which deposits cleaning liquid onto the wiping member; and a pressing device which presses and abuts the wiping member on which the cleaning liquid has been deposited, against the nozzle surface on which the cleaning liquid has been deposited by the nozzle surface cleaning liquid deposition device, and wipes the nozzle surface with the wiping member. 
         [0010]    According to the present invention, firstly, since the cleaning liquid is deposited onto the nozzle surface by the nozzle surface cleaning liquid deposition device, then it is possible to raise the dissolving effect, which is a chemical effect of dissolving adhering material which is adhering to the nozzle surface. Consequently, it is possible to remove the adhering material readily by subsequently wiping the nozzle surface with the wiping member, and hence the physical effects can also be improved. Furthermore, since the cleaning liquid is deposited so as to wet the wiping member, then it is possible to suppress the drawing out of liquid from the nozzles due to the absorbing characteristics of the wiping member, and therefore ejection defects due to solidification of drawn out liquid can be prevented. Consequently, it is possible to improve ejection stability of the droplet ejection head. 
         [0011]    It is preferable that the nozzle surface cleaning apparatus according to further aspect of the present invention further includes a first flow channel for supplying the cleaning liquid to the nozzle surface cleaning liquid deposition device; a second flow channel for supplying the cleaning liquid to the wiping member cleaning liquid deposition device; a common flow channel for supplying the cleaning liquid to the first flow channel and the second flow channel; and a switching device which can switch the cleaning liquid supplied from the common flow channel, to the first flow channel or the second flow channel. 
         [0012]    According to the nozzle surface cleaning apparatus relating to the further aspect of the present invention, switching of the cleaning liquid supplied from the common flow channel to the nozzle surface cleaning liquid deposition device or the wiping member cleaning liquid deposition device is carried out by the switching device, and therefore it is possible to simplify the apparatus. 
         [0013]    In the nozzle surface cleaning apparatus according to further aspect of the present invention, it is preferable that the switching device switches from the second flow channel to the first flow channel, when the nozzle surface of the droplet ejection head reaches a position of the nozzle surface cleaning liquid deposition device. 
         [0014]    According to the nozzle surface cleaning apparatus relating to the further aspect of the present invention, when the nozzle surface is situated at the position of the nozzle surface cleaning liquid deposition device, the switching device is switched and cleaning liquid is supplied to the nozzle surface cleaning liquid deposition device. Therefore, it is possible to deposit cleaning liquid on the wiping member up to that time. Consequently, the wiping member can be wetted by the time that the nozzle surface reaches the pressing device. 
         [0015]    In the nozzle surface cleaning apparatus according to further aspect of the present invention, it is preferable that the wiping member travel device includes a rewind and fast-forward device for rewinding and fast-forwarding the wiping member. 
         [0016]    According to the nozzle surface cleaning apparatus relating to the further aspect of the present invention, since the wiping member travel device includes a rewind and fast-forward device, then by depositing cleaning liquid onto a wiping member having a length required to clean the nozzle surface and then rewinding the wiping member, it is possible to reduce the space required for holding the wiping member. Furthermore, by fast-forwarding the wiping member, it is possible to speed up the application of cleaning liquid onto the wiping member. 
         [0017]    The nozzle surface cleaning apparatus according to another aspect of the present invention preferably includes: a first flow channel for supplying the cleaning liquid to the nozzle surface cleaning liquid deposition device; a second flow channel for supplying the cleaning liquid to the wiping member cleaning liquid deposition device; and a common flow channel for supplying the cleaning liquid to the first flow channel and the second flow channel, the second flow channel being provided with a flow channel resistance member. 
         [0018]    According to the nozzle surface cleaning apparatus relating to the another aspect of the present invention, the flow rate of the cleaning liquid is adjusted by providing a flow channel resistance member in the second flow channel for supplying cleaning liquid to the wiping member cleaning liquid deposition device. Consequently, since the amount of wetting of the wiping member can be adjusted, then it is possible to supply cleaning liquid to both the nozzle surface cleaning liquid deposition device and the wiping member cleaning liquid deposition device. Consequently, there is no need to deposit cleaning liquid over the whole of the wiping member which is used for cleaning, before moving the droplet ejection head, and hence the apparatus can be made compact in size. 
         [0019]    The nozzle surface cleaning apparatus according to another aspect of the present invention preferably includes a squeezing device which removes excess cleaning liquid from the wiping member on which the cleaning liquid has been deposited. 
         [0020]    According to the nozzle surface cleaning apparatus relating to the another aspect of the present invention, since it is possible to remove excess cleaning liquid of the cleaning liquid applied to the wiping member, then drawing out of the liquid is prevented, and wiping of the nozzle surface can be carried out without cleaning liquid remaining on the nozzle surface. Moreover, it is also possible to suppress dripping of liquid from the wiping member. 
         [0021]    Preferably, the nozzle surface cleaning apparatus according to another aspect of the present invention further includes a tank which stores cleaning liquid, the tank is provided above the nozzle surface cleaning liquid deposition device and the wiping member cleaning liquid deposition device, in a vertical direction, and supply of the cleaning liquid to the nozzle surface cleaning liquid deposition device and the wiping member cleaning liquid deposition device is performed by a liquid head differential. 
         [0022]    According to the nozzle surface cleaning apparatus relating to the another aspect of the present invention, the supply of the cleaning liquid can be performed by a liquid head differential without using a pump, and therefore it is possible to prevent non-uniformities in the deposition of cleaning liquid due to pulsation of a pump, or the like. 
         [0023]    In order to achieve the above object, the present invention provides an image recording apparatus, including: a conveyance device which conveys a recording medium; a droplet ejection head which records an image by ejecting liquid droplets onto the recording medium which is conveyed by the conveyance device; and the above described nozzle surface cleaning apparatus which cleans the nozzle surface of the droplet ejection head. 
         [0024]    According to the present invention, since a nozzle surface cleaning apparatus is provided, then ejection stability can be raised. 
         [0025]    In the image recording apparatus according to another aspect of the present invention, it is preferable that the droplet ejection head is provided in plurality in a conveyance path of the recording medium, and the nozzle surface cleaning apparatus is provided for each of the droplet ejection heads. 
         [0026]    The image recording apparatus relating to the another aspect of the present invention includes a nozzle surface cleaning apparatus for each droplet ejection head, and therefore it is possible appropriately to wipe each of the droplet ejection heads. 
         [0027]    According to the nozzle surface cleaning apparatus and the image recording apparatus of the present invention, since a nozzle surface cleaning liquid deposition device which deposits cleaning liquid on the nozzle surface and a wiping member cleaning liquid deposition device which deposits cleaning liquid on the wiping member are provided, then it is possible to improve the chemical effect of dissolving the adhering material by cleaning liquid, and since the adhering material is dissolved, then the physical effect of wiping by the wiping member can be improved. Moreover, since the drawing out of liquid by the wiping member can be prevented, then it is possible to stabilize the ejection directionality of the droplets. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]    The nature of this invention, as well as other objects and advantages thereof, will be explained in the following with reference to the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures and wherein: 
           [0029]      FIG. 1  is a front view diagram showing the composition of the principal part of an inkjet recording apparatus; 
           [0030]      FIG. 2  is a plan diagram showing the composition of the principal part of an inkjet recording apparatus; 
           [0031]      FIG. 3  is a side view diagram showing the composition of the principal part of an inkjet recording apparatus; 
           [0032]      FIG. 4  is a plan view perspective diagram of a nozzle surface of a head; 
           [0033]      FIG. 5  is a schematic drawing showing an approximate composition of a nozzle surface cleaning apparatus according to a first embodiment; 
           [0034]      FIG. 6  is a schematic drawing showing an approximate composition of a nozzle surface cleaning apparatus according to a modification of the first embodiment; and 
           [0035]      FIG. 7  is a schematic drawing showing an approximate composition of a nozzle surface cleaning apparatus according to a second embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0036]    Below, an inkjet recording apparatus is described as one example of an image recording apparatus, but the present invention is not limited to this. 
       First Embodiment 
     &lt;Composition of Inkjet Recording Apparatus&gt; 
       [0037]      FIG. 1  to  FIG. 3  are respectively a front view diagram, a plan diagram and a side view diagram showing a composition of the principal part of an inkjet recording apparatus relating to the present embodiment. 
         [0038]    As shown in  FIG. 1  to  FIG. 3 , this inkjet recording apparatus  10  is a single-pass type of line printer, which is principally constituted by a paper conveyance mechanism  20  for conveying paper (cut sheet paper) P serving as a recording medium, a head unit  30  which ejects ink droplets of respective colors of cyan (C), magenta (M), yellow (Y) and black (K) toward paper P which is conveyed by the paper conveyance mechanism  20 , a maintenance unit  40  which carries out maintenance of the respective heads installed on the head unit  30 , and a nozzle surface cleaning unit  80  which cleans the nozzle surfaces of the respective heads installed on the head unit  30 . 
         [0039]    The paper conveyance mechanism  20  is constituted by a belt conveyance mechanism and conveys the paper P horizontally by suctioning the paper P on a traveling belt  22 . 
         [0040]    The head unit  30  is principally constituted by a head  32 C which ejects cyan ink droplets, a head  32 M which ejects magenta ink droplets, a head  32 Y which ejects yellow ink droplets, a head  32 K which ejects black ink droplets, a head supporting frame  34  on which the heads  32 C,  32 M,  32 Y,  32 K are installed, and a head supporting frame movement mechanism (not illustrated) which moves the head supporting frame  34 . 
         [0041]    The heads (inkjet heads)  32 C,  32 M,  32 Y,  32 K are constituted by line heads which correspond to the maximum width of the paper P which is the object of printing. The heads  32 C,  32 M,  32 Y,  32 K each have the same composition, and are therefore referred to as the head  32  or heads  32  below, unless a specific head is to be distinguished. 
         [0042]    The heads  32  ( 32 C,  32 M,  32 Y,  32 K) are formed in a rectangular block shape, and nozzle surfaces  33  ( 33 C,  33 M,  33 Y,  33 K) are formed in the bottom portion of each head. 
         [0043]      FIG. 4  is a plan view perspective diagram of a nozzle surface of a head. 
         [0044]    The nozzle surface  33  is formed in a long shape, and nozzle rows are formed in the lengthwise direction thereof. The heads  32  according to the present embodiment are each composed by a so-called matrix head, in which nozzles N are arranged in a two-dimensional matrix configuration. In a matrix head, it is possible to reduce the effective pitch between nozzles N when projected in the lengthwise direction of the head  32 , and a high-density arrangement of the nozzles N can be achieved. 
         [0045]    Furthermore, the head  32  according to the present embodiment ejects droplets of ink from nozzles N by a so-called piezo jet system. The nozzles N are respectively connected to pressure chambers, and a droplet of ink is ejected from a nozzle N by causing a wall of the pressure chamber to vibrate by a piezo element. The ink ejection method is not limited to this and may also adopt a composition which performs ejection by a thermal method. 
         [0046]    The head supporting frame  34  includes a head installation section (not illustrated) for installing the heads  32 . The heads  32  are installed detachably in this head installation section. 
         [0047]    The heads  32  installed on the head supporting frame  34  are arranged perpendicularly with respect to the direction of conveyance of the paper P. Furthermore, the heads  32  are also arranged at a uniform interval apart in a prescribed order in the conveyance direction of the paper P (in the present example, the heads  32  are arranged in the order: cyan, magenta, yellow and black). 
         [0048]    Furthermore, the head installation section is provided so as to be raisable and lowerable on the head supporting frame  34 , and is raised and lowered by an elevator mechanism, which is not illustrated. The heads  32  which are installed on the head installation section are raised and lowered perpendicularly with respect to the conveyance surface of the paper P. 
         [0049]    The head supporting frame movement mechanism causes the head supporting frame  34  to slide horizontally in a direction which is perpendicular to the direction of conveyance of the paper P, at a position above the paper conveyance mechanism  20 . 
         [0050]    The head supporting frame movement mechanism is, for example, constituted by a ceiling frame which is disposed horizontally over the paper conveyance mechanism  20 , guide rails provided on the ceiling frame, a traveling body which slides over the guide rails, and a drive device which moves this traveling body along the guide rails (for example, a screw feed mechanism, or the like). The head supporting frame  34  is installed on the traveling body and slides horizontally. 
         [0051]    The head supporting frame  34  is driven by this head supporting frame movement mechanism, and is provided movably between a prescribed “image recording position” and a “maintenance position”. 
         [0052]    The head supporting frame  34  is arranged over the paper conveyance mechanism  20  when positioned at the image recording position. By this means, it is possible to carry out printing onto the paper P which has been conveyed by the paper conveyance mechanism  20 . 
         [0053]    On the other hand, when the head supporting frame  34  is positioned at the maintenance position, then it is disposed at the position where the maintenance unit  40  is disposed. 
         [0054]    Caps  42  ( 42 C,  42 M,  42 Y,  42 K) which cover the nozzle surfaces  33  of the heads  32  are provided in the maintenance unit  40 . When the apparatus is halted for a long period of time, for example, the heads  32  are moved to the arrangement position (maintenance position) of this maintenance unit  40  and the nozzle surfaces  33  are covered with the caps  42 . By this means, ejection failure due to drying is prevented. 
         [0055]    A pressurizing and suctioning mechanism (not illustrated) for pressurizing and suctioning the interior of the nozzles and a cleaning liquid supply mechanism (not illustrated) for supplying cleaning liquid to the interior of the caps  42  are provided in the caps  42 . Furthermore, a waste liquid tray  44  is provided at a position below the cap  42 . The cleaning liquid supplied to the cap  42  is discarded into this waste liquid tray  44  and is recovered into a waste liquid tank  48  from the waste liquid tray  44  via a waste liquid recovery pipe  46 . 
         [0056]    The nozzle surface cleaning apparatus  80  is constituted by a head cleaning liquid deposition apparatus  81  and a nozzle surface wiping apparatus  83 , and is arranged between the paper conveyance mechanism  20  and the maintenance unit  40 . The nozzle surface cleaning apparatus  80  deposits cleaning liquid on the nozzle surface  33  of the head  32  from the head cleaning liquid deposition apparatus  81 , when the head supporting frame  34  is moved from the image recording position to the maintenance position, and the nozzle surface  33  of the head  32  is wiped by a wiping web on which cleaning liquid has been deposited, by the nozzle surface wiping apparatus  83 , thereby cleaning the nozzle surface  33 . 
       &lt;Composition of Nozzle Surface Cleaning Apparatus&gt; 
       [0057]      FIG. 5  is a schematic drawing showing the approximate composition of the nozzle surface cleaning apparatus  80 . The nozzle surface cleaning apparatus  80  is constituted by a head cleaning liquid deposition apparatus  81  and a nozzle surface wiping apparatus  83 . The head cleaning liquid deposition apparatus  81  includes head cleaning liquid supply nozzles  84 C,  84 M,  84 Y,  84 K which deposit cleaning liquid onto the nozzle surfaces  33 C,  33 M,  33 Y,  33 K of the heads  32 C,  32 M,  32 Y,  32 K, and cleaning liquid holding surfaces  85 C,  85 M,  85 Y,  85 K on which cleaning liquid is held. The head cleaning liquid supply nozzles  84 C,  84 M,  84 Y,  84 K and the cleaning liquid holding surfaces  85 C,  85 M,  85 Y,  85 K are disposed on a cleaning liquid deposition apparatus main body  86 , in accordance with the deposition interval of the heads. The head cleaning liquid supply nozzles  84 C,  84 M,  84 Y,  84 K and the cleaning liquid holding surfaces  85 C,  85 M,  85 Y,  85 K each have the same composition, and therefore the compositions of a head cleaning liquid supply nozzle  84  and a cleaning liquid holding surface  85  are described below. 
         [0058]    Cleaning liquid supplied from the head cleaning liquid supply nozzle  84  is held on the cleaning liquid holding surface  85 . By moving the head  32  over the cleaning liquid holding surface  85  on which cleaning liquid is held, the cleaning liquid between the cleaning liquid holding surface  85  and the nozzle surface  33  wets and spreads using the lyophobic properties of the nozzle surface  33 , and the cleaning liquid can be applied to the nozzle surface  33 . Furthermore, the excess cleaning liquid which is not applied to the nozzle surface  33  and which remains on the cleaning liquid holding surface  85  is recovered into a recovery receptacle section  87 . 
         [0059]    The nozzle surface wiping apparatus  83  is constituted by wiping units  100 C,  100 M,  100 Y,  100 K which are installed on a wiping apparatus main body frame  82 , and a wiping apparatus main body elevator apparatus (not illustrated) which raises and lower the wiping apparatus main body frame  82 . 
         [0060]    The wiping units  100 C,  100 M,  100 Y,  100 K respectively abut a wiping web formed in a band shape against the nozzle surfaces  33  of the heads  32  while causing the wiping webs (with reference numeral  112  in  FIG. 5 ) to travel, thereby wiping the nozzle surfaces  33 . The wiping units  100 C,  100 M,  100 Y,  100 K are provided for each respective head and are arranged on the wiping apparatus main body frame  82  in accordance with the installation pitch of the heads  32 . The wiping units  100 C,  100 M,  100 Y,  100 K all have the same composition and therefore the composition is described here with respect to one wiping unit  100 . 
         [0061]    The wiping unit  100  which constitutes the nozzle surface wiping apparatus  83  includes a conveyance unit  110  that conveys a wiping web  112  (corresponding to a “wiping member travel device”), a cleaning liquid deposition unit  140  which supplies cleaning liquid to the wiping web  112 , and a cleaning liquid recovery unit  150  which recovers excess cleaning liquid from the wiping web  112  to which cleaning liquid has been supplied. Furthermore, the wiping unit  100  also includes a cleaning liquid supply unit  160  which supplies cleaning liquid to the head cleaning liquid deposition apparatus  81  and the nozzle surface wiping apparatus  83 . 
       &lt;Composition of Conveyance Unit&gt; 
       [0062]    The conveyance unit  110  includes: a pay out-side web core  114  which pays out a wiping web  112  before wiping; a take up-side web core  116  which takes up a wiping web  112  after wiping, by being driven to rotate by a take up motor (not illustrated); a first guide roller  118  which rotates while abutting against the wiping web  112  paid out from the pay out-side web core  114 , and guides the wiping web  112  to the cleaning liquid deposition unit  140  and a pressing roller  122  (corresponding to a “pressing device”); a pressing roller  122  which causes the wiping web  112  to abut against the nozzle surface  33  of the head  32  with a prescribed pressure; and a second guide roller  120  which guides the wiping web  112  after wiping to the take up-side web core  116 . 
         [0063]    The wiping web  112  is, for example, constituted by a knitted or woven sheet made of ultra-fine fibers of PET, PE, NY, or the like, and is formed in a band shape having a width corresponding to the width of the nozzle surface  33  of the head  32  being wiped. The wiping web  112  is supplied in a state of being wrapped in the form of a roll about a pay out-side web core  114 , the front end of the web being fixed to the take up-side core  116 . 
         [0064]    The first guide roller  118  is supported rotatably on a spindle which is disposed horizontally (not illustrated), and guides the wiping web  112  paid out from the pay out-side web core  114  towards the cleaning liquid deposition unit  140 . 
         [0065]    The pressing roller  122  is disposed horizontally, one end of the spindle portion thereof being supported in a rotatable fashion. The pressing roller  122  is constituted by a rubber roller corresponding to the width of the wiping web  112 , and causes the wiping web  112  to abut against the nozzle surface  33  of the head  32  with a prescribed pressure. 
         [0066]    The second guide roller  120  is supported rotatably on a spindle which is disposed horizontally (not illustrated), and guides the wiping web  112  conveyed from the pressing roller  122  towards the take up-side web core  116 . 
         [0067]    As described above, the wiping web  112  is provided in the form of a roll on the pay out-side web core  114 , and can therefore be installed (replaced) on the wiping unit  100  in this state. More specifically, after the pay out-side web core  114  has been installed by fitting onto a pay out spindle, the wiping web  112  is wrapped in order about the first guide roller  118 , the pressing roller  122  and the second guide roller  120 , and the take up-side web core  116  is fitted onto a take up spindle, thereby completing installation. 
       &lt;Composition of Cleaning Liquid Deposition Unit&gt; 
       [0068]    The cleaning liquid deposition unit  140  is principally constituted by a web cleaning liquid supply nozzle  142  (corresponding to a “wiping member cleaning liquid deposition device”). The web cleaning liquid supply nozzle  142  has a spray port of a width corresponding to the width of the wiping web  112 , and sprays cleaning liquid from this spray port. The web cleaning liquid supply nozzle  142  is disposed so as to spray cleaning liquid in an upward direction. Cleaning liquid is sprayed from the spray port and thereby deposited onto the wiping web  112 , when the wiping web  112  passes over this web cleaning liquid supply nozzle  142 . Consequently, cleaning liquid is absorbed inside the wiping web  112 . 
       &lt;Composition of Cleaning Liquid Recovery Unit&gt; 
       [0069]    The cleaning liquid recovery unit  150  is principally constituted by a squeeze roller pair  151  (corresponding to a “squeezing device”), a recovery receptacle member  152 , and a moisture meter  153 . 
         [0070]    The squeeze roller pair  151  is a pressurizing device which is constituted by two mutually opposing rollers. The squeeze rollers have a width corresponding to the width of the wiping web  112 , and are made from a rubber, such as silicone or EPDM, or a metal such as stainless steel, which is not destroyed by the cleaning liquid. 
         [0071]    The squeeze roller pair  151  is disposed in the conveyance path of the wiping web  112  and to the downstream side of the web cleaning liquid supply nozzle  142 . The squeeze roller pair  151  sandwiches and presses the wiping web  112  on which the cleaning liquid has been deposited, and squeezes out the cleaning liquid from the wiping web  112 . By this means, excess cleaning liquid is recovered from the wiping web  112 , and the wiping web  112  is wetted with a suitable amount of cleaning liquid. 
         [0072]    A moisture meter  153 , which is a measurement device for measuring the amount of cleaning liquid in the wiping web  112 , is arranged to the downstream side of the squeeze roller pair  151 . The amount of cleaning liquid in the wiping web  112  is measured by the moisture meter  153 . By controlling a pressure adjustment mechanism (not illustrated) of the squeeze rollers in accordance with the amount of cleaning liquid measured by this moisture meter  153 , it is possible to control the amount of cleaning liquid in the wiping web  112  after recovery of cleaning liquid, to a suitable amount. 
         [0073]    Furthermore, a recovery receptacle member  152  which recovers the squeezed cleaning liquid is provided below the squeeze roller pair  151 . The cleaning liquid recovered into the recovery receptacle member  152  is sent to a main tank  161  for reuse, after passing through a filter (not illustrated) to remove impurities. 
         [0074]    In this way, the wiping web  112  which has been wetted by a suitable amount of cleaning liquid is abutted and pressed against the nozzle surface  33  by the pressing roller  122 , and the nozzle surface  33  is wiped successively by an unused region of the wiping web  112 . 
       &lt;Composition of Cleaning Liquid Supply Unit&gt; 
       [0075]    The cleaning liquid supply unit  160  includes a main tank  161  which stores cleaning liquid, a reserve tank  162  which temporarily stores cleaning liquid, a control valve  163  which controls a flow rate, and a flow channel switching valve  164  which switches the supply destination of the cleaning liquid. 
         [0076]    The main tank  161  is connected to the reserve tank  162  via a flow channel  166 . The cleaning liquid in the main tank  161  is conveyed along the flow channel  166  by a pump  165  which is provided at an intermediate point of the flow channel  166 . The reserve tank  162  is connected to the flow channel switching valve  164  via a flow channel  167 . A control valve  163  is provided in the flow channel  167  and controls a flow rate of cleaning liquid from the reserve tank  162 . The reserve tank  162  is desirably provided at a position higher than the nozzle surface cleaning apparatus  80 , in such a manner that cleaning liquid can be supplied to the nozzle surface cleaning apparatus  80  using a liquid head differential. By supplying cleaning liquid using a liquid head differential, it is possible to supply cleaning liquid without being affected by a pulsating action of the pump, and therefore non-uniformities in the deposition of cleaning liquid can be prevented. 
         [0077]    The flow channel switching valve  164  is connected to a head cleaning liquid flow channel  168  (which corresponds to a “first flow channel”) and a web cleaning liquid flow channel  169  (which corresponds to a “second flow channel”). The head cleaning liquid flow channel  168  is connected to the head cleaning liquid supply nozzle  84  and the web cleaning liquid flow channel  169  is connected to the web cleaning liquid supply nozzle  142 . By means of the flow channel switching valve  164 , a composition is achieved in which the flow channel  167  can be connected to either the head cleaning liquid flow channel  168  or the web cleaning liquid flow channel  169 , and the supply of the cleaning liquid to the head cleaning liquid supply nozzle  84  or the web cleaning liquid supply nozzle  142  can be switched by switching this flow channel switching valve  164 . 
         [0078]    Here, the main tank  161  and the reserve tank  162  are provided for each head cleaning liquid supply nozzle  84  and each wiping unit  100 , but it is also possible to adopt a composition in which one main tank  161 , one pump  165  and one reserve tank  162  are used commonly for each of the head cleaning liquid supply nozzles  84 C,  84 M,  84 Y,  84 K, and each of the wiping units  100 C,  100 M,  100 Y,  100 K. In this case, cleaning liquid is supplied from the one reserve tank  162 , via the flow channels  167 C,  167 M,  167 Y,  167 K and three-way valves  164 C,  164 M,  164 Y,  164 K to the head cleaning liquid supply nozzles  84 C,  84 M,  84 Y,  84 K or the web cleaning liquid supply nozzles  142 C,  142 M,  142 Y,  142 K, and then sprayed from the respective nozzles. 
       &lt;Action of Nozzle Surface Cleaning Apparatus&gt; 
       [0079]    Next, the action of the nozzle surface cleaning apparatus  80  which is composed as described above will be explained. The nozzle surface cleaning apparatus  80  wipes the nozzle surface  33  during the course of the movement of the head  32  from an image recording position to a maintenance position. 
         [0080]    The head cleaning liquid deposition apparatus  81  and the nozzle surface wiping apparatus  83  which constitute the nozzle surface cleaning apparatus  80  are composed so as to be raisable and lowerable in their entirety, by an elevator mechanism. The head cleaning liquid deposition apparatus  81  and the nozzle surface wiping apparatus  83  are situated at a prescribed standby position when cleaning is not being performed, and during cleaning, are situated at a prescribed operating position which is raised by a prescribed amount with respect to the standby position. 
         [0081]    In a state where the head cleaning liquid deposition apparatus  81  is situated in the operating position, it is possible to deposit cleaning liquid onto the nozzle surfaces  33  of the heads  32  by the cleaning liquid which is held on the cleaning liquid holding surfaces  85 . In other words, when the heads  32  pass the head cleaning liquid deposition apparatus  81 , cleaning liquid can be applied to the nozzle surfaces due to the nozzle surfaces coming into contact with the cleaning liquid held on the cleaning liquid holding surfaces  85 . Furthermore, when the nozzle surface wiping apparatus  83  is situated in the operating position, it is possible to wipe the nozzle surfaces  33  with the wiping units  100 . In other words, when each of the heads  32  passes the respective wiping units  100 , a wiping web  112  which is wrapped about the pressing roller  122  can be abutted and pressed against the nozzle surfaces  33  of the heads  32 . 
         [0082]    When the head enters into nozzle surface cleaning mode, the heads  32  are moved from an image recording position to a maintenance position, by a head movement device (not illustrated). When the heads  32  reach a prescribed position, the wiping webs  112  are conveyed in an opposite direction to the direction of travel of the heads  32  by the conveyance unit  110 . In other words, driving of the take up motor is started, whereby the wiping webs  112  are each paid out from the pay out-side web core  114  and travel so as to be taken up on the take up-side web core  116 . 
         [0083]    In this case, a friction is applied to the pay out spindle of the pay out-side web core  114  by a friction mechanism, and the take up spindle of the take up-side web core  116  slides when a prescribed load or greater is applied by a torque limiter, thereby making it possible to apply a prescribed tension to the wiping web  112  while the web travels. 
         [0084]    Simultaneously with the start of conveyance of the wiping web  112 , the control valve  163  and the flow channel switching valve  164  are controlled and cleaning liquid is ejected from the web cleaning liquid supply nozzle  142  to wet the wiping web  112 . The web cleaning liquid supply nozzle  142  upwardly sprays cleaning liquid conveyed from the reserve tank  162  due to the liquid head differential. This sprayed cleaning liquid is deposited onto the wiping web  112 , when the wiping web  112  passes over the web cleaning liquid supply nozzle  142 . Consequently, cleaning liquid is absorbed inside the wiping web  112 . In this case, cleaning liquid of a prescribed amount which is greater than the amount of cleaning liquid suitable for wiping and cleaning the nozzle surface  33  is deposited on the wiping web  112 . For example, cleaning liquid of an amount which saturates the absorption capability of the wiping web  112  is deposited. 
         [0085]    The excessively deposited cleaning liquid in the wiping web  112  is squeezed out from the wiping web  112  by the squeeze roller pair  151 , thereby adjusting the amount of cleaning liquid deposited in the wiping web  112 . Consequently, the excessive cleaning liquid is recovered from the wiping web  112 , and the wiping web  112  assumes a state of being wetted by a suitable amount of cleaning liquid (an amount suitable for wiping the nozzle surface  33  and for wiping away cleaning liquid which has been deposited by the head cleaning liquid deposition apparatus  81 ). In this way, by recovering excessive cleaning liquid and wetting the wiping web  112  with a suitable amount of cleaning liquid, it is possible to suppress the drawing out of ink from the nozzles N during wiping of the nozzle surface  33 . In the foregoing description, a composition is explained in which an amount of cleaning liquid greater than an amount of cleaning liquid suited for wiping and cleaning is deposited and cleaning liquid is recovered by the squeeze roller pair  151 , but it is also possible to deposit an amount of cleaning liquid which is suited to wiping and cleaning from the web cleaning liquid supply nozzle  142 . 
         [0086]    The amount of cleaning liquid in the wiping web  112  from which cleaning liquid has been recovered by the squeeze roller pair  151  is measured by the moisture meter  153 . By controlling a pressure of the squeeze roller pair  151  in accordance with this measured amount of cleaning liquid, it is possible to control the amount of cleaning liquid in the wiping web  112  after cleaning liquid recovery by the squeezing roller pair  151 , to a suitable amount. By using feedback control in this way, it is possible to control the amount of lubrication of the wiping web  112  with even greater accuracy. 
         [0087]    After the head  32  has been moved to a position directly in front of the head cleaning liquid deposition apparatus  81 , the flow channel switching valve  164  is controlled so as to eject cleaning liquid from the head cleaning liquid supply nozzle  84 , and the cleaning liquid is held on the cleaning liquid holding surface  85 . Due the nozzle surface  33  of the head passing over the cleaning liquid holding surface  85  on which cleaning liquid is held, the cleaning liquid layer formed between the nozzle surface  33  and the cleaning liquid holding surface  85  makes contact with the nozzle surface  33  and cleaning liquid is thereby applied to the nozzle surface  33 . 
         [0088]    The nozzle surface  33  onto which cleaning liquid has been applied is wiped by the wetted wiping web  112  of the nozzle surface wiping apparatus  83 . The wiping web  112  is abutted and pressed while applying a suitable pressure against the nozzle surface  33  by the pressing roller  122 , while travelling due to the driving of the take up motor, whereby the nozzle surface  33  is wiped and cleaned. 
         [0089]    During this, the wiping web  112  wipes the nozzle surface  33  while traveling in the opposite direction to the direction of movement of the nozzle surface  33 . By this means, the nozzle surface  33  can be wiped efficiently. Furthermore, it is also possible to perform wiping of the nozzle surface  33 , by using a new surface (unused region) of the wiping web  112  at all times. 
         [0090]    The wiping web  112  which has wiped the nozzle surface  33  is taken up onto the take up-side web core  116 . Furthermore, the head  32  is moved to the maintenance position and the nozzle surface  33  is covered with a cap  42 . 
         [0091]    In this way, dirt on the nozzle surface  33  is softened by the cleaning liquid which has been applied from the head cleaning liquid deposition apparatus  81 , and therefore the dirt can subsequently be removed easily by the wiping of the wiping web  112  of the nozzle surface wiping apparatus  83 . Therefore, it is possible to reduce the pressure applied to the nozzle surface  33  by the pressing roller  122 , and hence the damage caused to the lyophobic treatment on the nozzle surface  33  can be minimized. 
         [0092]    Furthermore, unwanted cleaning liquid remaining on the nozzle surface, of the cleaning liquid which has been applied by the head cleaning liquid deposition apparatus  81 , is wiped away by the wiping web  112  of the nozzle surface wiping apparatus  83 . The wiping web  112  is wetted suitably by the cleaning liquid, in other words, wetted to an extent which allows excess cleaning liquid remaining on the nozzle surface  33  to be absorbed, and therefore it is possible to prevent ink from being drawn out from the nozzles N and soiling the nozzle surface  33 . Consequently, there is no solidification of ink which has been drawn out and this solidified material is not pushed inside the head  32  during the subsequent wiping action, and therefore the ejection characteristics can be improved. 
         [0093]    In the embodiment described above, it is necessary to wet the wiping web  112  through a length required for wiping the length of the nozzle surface  33  in the conveyance direction, until the head  32  passes over the head cleaning liquid deposition apparatus  81 , and therefore the length from the pressing roller  122  to the web cleaning liquid supply nozzle  142  must be the same as the length of the wiping web  112  required to wipe the nozzle surface  33 . Consequently, it is necessary to control the movement speed of the head  32 , the conveyance speed of the wiping web  112 , the distance between the pressing roller  122  and the web cleaning liquid supply nozzle  142 , and the distance between the head cleaning liquid supply nozzle  84  and the pressing roller  122 , and the like. In particular, if the conveyance speed of the wiping web  112  is slow, then it is necessary to lengthen the distance between the pressing roller  122  and the web cleaning liquid supply nozzle  142 , and hence there have been major restrictions on the layout of the apparatus. 
         [0094]    Therefore, by providing a mechanism for controlling fast-forwarding and rewinding of the wiping web  112 , in the conveyance unit  110 , it is possible to reduce the size of the layout of the nozzle surface wiping apparatus  83 . More specifically, firstly, cleaning liquid is deposited by the web cleaning liquid supply nozzle  142  so as to wet the wiping web  112  through a length necessary to wipe the length of the nozzle surface  33  in the conveyance direction. Thereupon, the wiping web  112  is rewound in such a manner that the leading position, in the conveyance direction, of the portion of the wiping web  112  on which cleaning liquid has been deposited becomes the portion which contacts the nozzle surface  33  on the pressing roller  122 . 
         [0095]    Thereupon, the flow channel is switched by the flow channel switching valve  164 , in accordance with the movement of the head  32 , and cleaning liquid is supplied to the head cleaning liquid supply nozzle  84 , thereby applying cleaning liquid to the nozzle surface  33 . When the head  32  has reached the pressing roller  122  of the nozzle surface wiping apparatus  83 , the conveyance of the wiping web  112  is started again, whereby the nozzle surface  33  can be cleaned and excess cleaning liquid can be wiped away. 
         [0096]    By adopting a composition of this kind, it is possible to shorten the distance between the head cleaning liquid supply nozzle  84  and the pressing roller  122 , and to shorten the distance between the pressing roller  122  and the web cleaning liquid supply nozzle  142 , and therefore the nozzle surface cleaning apparatus  80  can be made more compact in size. Furthermore, it is also possible to prevent dripping of liquid before the cleaning liquid deposited on the nozzle surface  33  by the head cleaning liquid deposition apparatus  81  is wiped by the nozzle surface wiping apparatus  83 . 
       MODIFICATION EXAMPLES 
       [0097]      FIG. 6  is a schematic drawing showing an approximate composition of a modification of a nozzle surface cleaning apparatus  280  relating to a first embodiment of the invention. The nozzle surface cleaning apparatus  280  shown in  FIG. 6  supplies cleaning liquid to the head cleaning liquid supply nozzle  84  from the reserve tank  162  via a head cleaning liquid flow channel  268  and a control valve  263   a . Furthermore, the web cleaning liquid supply nozzle  142  is connected to the web cleaning liquid supply nozzle  142  via a web cleaning liquid flow channel  269  and a control valve  263   b . In this way, the nozzle surface cleaning apparatus  280  shown in  FIG. 6  differs from the nozzle surface cleaning apparatus  80  shown in  FIG. 5  in that cleaning liquid is supplied to the head cleaning liquid supply nozzle  84  and to the web cleaning liquid supply nozzle  142  by respective flow channels from the reserve tank  162 . 
         [0098]    As shown in  FIG. 6 , by supplying cleaning liquid from the reserve tank  162  via the respective flow channels, it is possible to supply cleaning liquid independently to the head cleaning liquid supply nozzle  84  and the web cleaning liquid supply nozzle  142 . Consequently, cleaning liquid can be ejected simultaneously from the head cleaning liquid supply nozzle  84  and the web cleaning liquid supply nozzle  142 , and therefore the restrictions on the layout of the nozzle surface cleaning apparatus are reduced and hence the size of the apparatus can be made more compact. 
       Second Embodiment 
       [0099]      FIG. 7  is a schematic drawing showing a schematic composition of a nozzle surface cleaning apparatus  380  relating to a second embodiment of the invention. The nozzle surface cleaning apparatus  380  relating to the second embodiment differs from the nozzle surface cleaning apparatus relating to the first embodiment in that a flow channel resistance  370  is provided in the web cleaning liquid flow channel  369 , instead of the flow channel switching valve. 
         [0100]    By providing a flow channel resistance  370  in the web cleaning liquid flow channel  369 , it is possible to deposit cleaning liquid simultaneously while altering the flow rate of the cleaning liquid from the head cleaning liquid supply nozzle  84  and the web cleaning liquid supply nozzle  142 . The flow channel resistance  370  is provided in such a manner that the flow rate of cleaning liquid in the web cleaning liquid flow channel  369  is lower than the flow rate in the head cleaning liquid flow channel  368 . By adopting a composition of this kind, the restrictions on the layout of the nozzle surface cleaning apparatus are reduced, and therefore the apparatus can be made more compact in size. By adopting a composition of this kind, there is no need to provide a fast-forward and rewind mechanism, and the apparatus can be made compact in size. 
         [0101]    For the flow channel resistance  370 , it is possible to use a narrow-diameter tube or a filter, or the like. Furthermore, it is also possible to create a resistance in the flow channel and to reduce the flow rate by pinching a tube using a valve or cam. 
         [0102]    More specifically, in order to eject a liquid flow of 45 ml/min from the head cleaning liquid supply nozzle  84  and 5 ml/min from the web cleaning liquid supply nozzle  142 , it is possible to use a flow resistance of 0.5 diameter by 50 mm length. The normal flow channel size is a flow channel of 4 mm diameter (internal diameter) by 6 mm diameter (outer diameter). In this case, by setting the head movement speed to 20 mm/sec and setting the wiping web conveyance speed to 3.2 mm/sec, it is possible to achieve a nozzle surface which is clean and on which there is no drawing out of the ink after wiping. 
         [0103]    It should be understood, however, that there is no intention to limit the invention to the specific forms disclosed, but on the contrary, the invention is to cover all modifications, alternate constructions and equivalents falling within the spirit and scope of the invention as expressed in the appended claims.