JP5457386B2 - Head cleaning apparatus and method, and ink jet recording apparatus - Google Patents

Description

  The present invention relates to a head cleaning apparatus and method and an ink jet recording apparatus, and more particularly to a head cleaning apparatus and method and an ink jet recording apparatus for cleaning a nozzle surface of an ink jet head.

  In the ink jet recording apparatus, if the nozzle surface of the ink jet head (surface on which the nozzles are formed) is dirty, defective ejection occurs. For this reason, in the ink jet recording apparatus, the nozzle surface is periodically cleaned.

  Patent Document 1 describes a method of cleaning a nozzle surface by spraying a cleaning liquid to which an ultrasonic wave is applied onto the nozzle surface.

  Patent Document 2 describes a method of wiping the nozzle surface with a foam impregnated with a cleaning solvent, and applying ultrasonic vibration to the foam.

JP 2005-28758 A JP 2010-58473 A

  However, as disclosed in Patent Document 1, there is a drawback in that stains firmly adhered to the nozzle surface cannot be removed simply by spraying the cleaning liquid to which the ultrasonic waves are applied onto the nozzle surface. Further, since the cleaning liquid is dripped immediately, there is a drawback that it is difficult to obtain the effect of removing dirt by ultrasonic waves.

  Moreover, in patent document 2, since dirt accumulate | stores in a foam, there exists a fault that a cleaning effect falls with progress of time.

  SUMMARY An advantage of some aspects of the invention is that it provides a head cleaning device and method, and an ink jet recording apparatus that can effectively remove stains on an ink jet head and maintain stable cleaning performance. To do.

  Means for solving the problems are as follows.

  [1] A first aspect of the head cleaning device is a head cleaning device for cleaning a nozzle surface of an ink jet head, a pressure roller pressed against the nozzle surface, a web wound around the pressure roller, A feeding shaft that unwinds the web; a winding shaft that winds the web; and a guide member that guides the web that is unwound from the feeding shaft and wound around the winding shaft so as to be wound around the pressing roller. And a web driving means for running the web, a cleaning liquid applying means for applying a cleaning liquid to the web wound around the pressing roller, and an ultrasonic wave generating means for applying an ultrasonic wave to the cleaning liquid. And

  According to this aspect, the cleaning liquid in which ultrasonic waves are applied to the web for wiping the nozzle surface is applied. The ultrasonic wave is propagated to the nozzle surface through the cleaning liquid that has penetrated the web. Thereby, the solubility of the dirt adhering to the nozzle surface can be improved. In addition, since the nozzle surface is wiped by the web, even dirt that adheres firmly can be removed reliably. Further, since the web runs, it always comes into contact with the nozzle surface at a new site. Thereby, stable cleaning performance can be maintained.

  [2] A second aspect of the head cleaning device is the head cleaning device according to the first aspect, wherein the ink jet head has the nozzle surface arranged substantially vertically, and the pressing roller is horizontal and the nozzle surface. The guide member is arranged in parallel, and guides the web so that the web runs obliquely downward toward the pressing roller or obliquely upward from the pressing roller. The cleaning liquid is applied from above the web to a portion where the web runs obliquely downward toward the pressing roller or a portion where the web runs obliquely upward from the pressing roller. To do.

  According to this aspect, the web wound around the pressure roller is guided so as to travel obliquely downward toward the pressure roller or to travel obliquely upward from the pressure roller. And the washing | cleaning liquid is provided with respect to the web guided in this way from the upper direction of a web. As a result, the cleaning liquid applied to the web flows down to the nozzle surface along the web, and the cleaning liquid can be efficiently guided to the nozzle surface.

  [3] A third aspect of the head cleaning device according to the second aspect is the head cleaning device according to the second aspect, wherein the cleaning liquid applying means is saturated in the web so that a film of the cleaning liquid is formed on the surface of the web. The amount of the cleaning liquid is more than that amount.

  According to this aspect, a cleaning liquid having a saturation amount or more is applied to the web, and a film of the cleaning liquid is formed on the surface of the web. Thereby, the cleaning liquid to which the ultrasonic wave is applied is directly applied to the nozzle surface through the film of the cleaning liquid. Thereby, the cleaning effect by ultrasonic waves can be further enhanced.

  [4] A fourth aspect of the head cleaning device is characterized in that in the head cleaning device of the third aspect, a recovery dish for recovering the cleaning liquid dripping from the web is further provided.

  According to this aspect, the cleaning liquid targeted from the web is recovered in the recovery dish. Thereby, surrounding contamination can be prevented.

  [5] A fifth aspect of the head cleaning device is the head cleaning device according to any one of the first to fourth aspects, wherein the cleaning liquid application unit applies the cleaning liquid from a nozzle, and the ultrasonic wave generation unit It is installed in a nozzle and the ultrasonic wave is applied to the cleaning liquid in the nozzle.

  According to this aspect, the ultrasonic wave generating means is installed in the nozzle that applies the cleaning liquid. Thereby, an ultrasonic wave can be applied to the cleaning liquid at a position close to the nozzle surface, and the ultrasonic cleaning effect can be further enhanced.

  [6] A first aspect of the head cleaning method is a method for cleaning an inkjet head using the head cleaning device of the third aspect, wherein the cleaning liquid to which the ultrasonic wave is applied is applied to the web. The head cleaning is performed by causing the web to run, causing the pressure roller to contact the nozzle surface, moving the pressure roller and the nozzle surface relatively vertically, and wiping the nozzle surface with the web. In the method, the pressure roller and the nozzle surface are relatively moved in the vertical direction with the cleaning liquid pool formed between the nozzle surface and the pressure roller, and the nozzle surface is moved by the web. It is characterized by wiping.

  According to this aspect, the cleaning liquid pool is formed between the pressing roller and the nozzle surface, and wiping is performed. Thereby, the contact time of the cleaning liquid to which the ultrasonic wave is applied can be lengthened, and the cleaning effect by the ultrasonic wave can be improved. The liquid reservoir can be formed, for example, by bringing the pressing roller into contact with the nozzle surface with a predetermined pressing force in a state where the relative movement in the vertical direction between the pressing roller and the nozzle surface is stopped. Therefore, after the liquid reservoir is formed in this way, the nozzle surface can be wiped while maintaining the liquid reservoir by relatively moving the pressing roller and the nozzle surface in the vertical direction.

  [7] A second aspect of the head cleaning method is a method of cleaning an inkjet head using the head cleaning device of the second aspect, while applying the cleaning liquid to which the ultrasonic waves are applied to the web. The head cleaning is performed by causing the web to run, causing the pressure roller to contact the nozzle surface, moving the pressure roller and the nozzle surface relatively vertically, and wiping the nozzle surface with the web. In the method, the pressure roller and the nozzle surface are relatively moved in the vertical direction a plurality of times to wipe the nozzle surface with the web, and at least once, the cleaning liquid having a saturation amount or more is applied to the web. The nozzle surface is wiped off, and at least the last time, the cleaning liquid is applied in such an amount that it penetrates the web to wipe the nozzle surface. Characterized in that it.

  According to this aspect, the nozzle surface is wiped a plurality of times. Then, at least one of a plurality of times, a cleaning liquid of a saturation amount or more is applied to the web and wiped. In addition, at least the last of the plurality of times, the cleaning liquid is applied to the web in an application amount enough to penetrate the web and wiped off. For example, when wiping twice (when reciprocating and wiping), the first time (outward path) is wiped by applying a cleaning liquid of a saturated amount or more to the web, and the second time (return path) is enough to penetrate the web. A cleaning liquid is applied to the web in an applied amount and wiped. Also, for example, when wiping four times, the first to third times apply a cleaning liquid of a saturated amount or more to the web to wipe it, and finally apply the cleaning liquid to the web in an application amount that penetrates the web. Wipe away. Alternatively, in the first and second times, a cleaning liquid of a saturation amount or more is applied to the web and wiped, and in the third and fourth times, the cleaning liquid is applied to the web and wiped with an application amount that penetrates the web. Thereby, dirt can be effectively wiped off without causing unwiping.

  [8] A third aspect of the head cleaning method is a method for cleaning an inkjet head using the head cleaning device of the second aspect, while applying the cleaning liquid to which the ultrasonic waves are applied to the web. The web is run, the pressure roller is brought into contact with the nozzle surface, the pressure roller and the nozzle surface are relatively reciprocated in the vertical direction, and the nozzle surface is wiped with the web. In the head cleaning method, when the pressing roller moves downward relative to the nozzle surface, the cleaning liquid of a saturation amount or more is applied to the web to wipe the nozzle surface, and the pressing roller In the case of moving upward relative to the nozzle surface, the cleaning liquid is applied in an application amount sufficient to penetrate the web, and the nozzle surface is moved. Characterized in that it wipe.

  According to this aspect, the nozzle surface is wiped by reciprocating the pressure roller relative to the nozzle surface in the vertical direction. At this time, when the pressing roller moves downward relative to the nozzle surface, a cleaning liquid of a saturation amount or more is applied to the web, and the nozzle surface is wiped off. Further, when the pressing roller moves in the upward direction relative to the nozzle surface, the cleaning liquid is applied to the web in such an amount that it penetrates the web, and the nozzle surface is wiped away. Thereby, dirt can be effectively wiped off without causing unwiping.

  [9] A fourth aspect of the head cleaning method is characterized in that, in the head cleaning method of the first to third aspects, the pressure in the nozzles of the inkjet head is set to a positive pressure and the nozzle surface is wiped off. To do.

  According to this aspect, the pressure on the nozzle surface is set to a positive pressure during wiping. Thereby, it is possible to prevent the cleaning liquid from being drawn into the nozzle.

  [10] A fifth aspect of the head cleaning method is characterized in that, in the head cleaning method according to the first to fourth aspects, the ultrasonic wave of 400 kHz or more is applied to the cleaning liquid.

  According to this aspect, an ultrasonic wave of 400 kHz or higher is applied to the cleaning liquid. Thereby, the fine dirt (stain of several μm) adhering to the nozzle surface can be effectively removed. In addition, the breakage of the liquid repellent film formed on the nozzle surface can be prevented.

  [11] A first aspect of the ink jet recording apparatus includes the head cleaning apparatus according to any one of the first to fifth aspects.

  According to this aspect, it is possible to effectively remove stains on the nozzle surface of the ink jet head incorporated in the ink jet recording apparatus. Thereby, a high quality image can be recorded without causing a discharge failure.

  According to the present invention, dirt on the nozzle surface of the inkjet head can be effectively removed, and stable cleaning performance can be maintained.

Side view showing schematic configuration of recording unit of inkjet recording apparatus Front view showing schematic configuration of recording unit of inkjet recording apparatus Side sectional view of the head cleaning device Front view of head cleaning device Cross section of cleaning liquid supply nozzle Explanatory drawing of the cleaning operation by the head cleaning device Side surface sectional view of the second embodiment of the head cleaning device Front view of the second embodiment of the head cleaning device Explanatory drawing of the cleaning operation by the head cleaning device The flowchart which shows the procedure of the process in the case of wiping a nozzle surface several times Explanatory drawing of cleaning operation when wiping nozzle surface multiple times Side sectional view of the third embodiment of the head cleaning device

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[First Embodiment]
[Constitution]
FIG. 1 is a side view illustrating a schematic configuration of a recording unit of an ink jet recording apparatus, and FIG. 2 is a front view thereof.

  The ink jet recording apparatus of this example is a so-called line printer, and records an image on the medium M using a line type ink jet head 10 (hereinafter referred to as a head).

  The medium M is so-called roll paper (continuous paper). The medium M is transported along a predetermined transport path at a constant transport speed by a media transport mechanism (not shown). In this example, in the recording unit, the medium M is guided by the guide roller 20 and conveyed vertically.

  As described above, the head 10 is a line-type head (line head), and is formed corresponding to the width of the medium M (recordable in one pass in the entire width direction of the medium M). ). A nozzle surface 12 is formed at the tip of the head 10. A nozzle 14 is provided on the nozzle surface 12. A large number of nozzles 14 are arranged along the longitudinal direction (width direction) of the nozzle surface 12. The head 10 of this example is a so-called matrix head, and the nozzles 14 are arranged on the nozzle surface 12 in a matrix.

  The head 10 is mounted on the head mount 16. By being mounted on the head mount 16, the head 10 is arranged orthogonal to the transport direction of the medium M transported through the recording unit, and the nozzle surface 12 of the head 10 and the medium M transported through the recording unit Arranged in parallel.

  The head mount 16 is provided so as to be movable in the front-rear direction (a direction perpendicular to the recording surface of the medium M conveyed through the recording unit) by a front-rear moving mechanism (not shown), and is also moved in the vertical direction (the recording unit is moved by a vertical movement mechanism not shown). It is provided so as to be movable in the conveyance direction of the medium M to be conveyed. Further, it is provided so as to be movable in the left-right direction (direction perpendicular to the transport direction of the medium M transported through the recording unit (width direction of the medium M)) by a left-right moving mechanism (not shown).

  The head mount 16 moves in the left-right direction to move the head 10 to the image recording position and the cleaning position.

  The head 10 can record an image on the medium M conveyed through the recording unit by moving to the image recording position. That is, the nozzle surface 12 is arranged facing the medium M conveyed through the recording unit.

  Further, the head 10 is moved to the cleaning position, so that the nozzle surface 12 can be cleaned by the head cleaning device 30A.

  FIG. 3 is a side sectional view of the head cleaning device. FIG. 4 is a front view of the head cleaning device.

  The head cleaning device 30A is installed in the head cleaning unit of the ink jet recording apparatus, and cleans the nozzle surface 12 of the head 10 moved to the cleaning position by wiping with a web.

  The head cleaning device 30 </ b> A mainly includes a main body frame 32, a web 34 for wiping the nozzle surface 12, a feeding shaft 36 for feeding the web 34, a winding shaft 38 for winding the web 34, and the web 34 for the nozzle surface 12. The first roller 42 and the second guide roller 44 that guide the travel of the web 34, the web drive motor 46 that travels the web 34, and the cleaning liquid in which ultrasonic waves are applied to the web 34. And a forward / backward drive mechanism 50 for moving the main body frame 32 forward / backward with respect to the head 10.

  The main body frame 32 includes a main body portion 32A formed in a rectangular plate shape, and plate-like support portions 32B and 32B provided at both ends of the main body portion 32A. The main body 32A is disposed in parallel with the nozzle surface 12 of the head 10 that has moved to the cleaning position. The support portions 32B and 32B are provided at right angles to both ends of the main body portion 32A toward the head 10 moved to the cleaning position.

  The web 34 is composed of an absorbent wiping cloth (for example, a knitted and knitted fabric of ultrafine long fibers), and is formed in a strip shape having a width corresponding to the width of the nozzle surface 12 of the head 10. The web 34 is wound in a roll shape around a cylindrical core. A winding core is attached to the tip of the web 34.

  The feeding shaft 36 is formed in a round bar shape, and is attached to the main body frame 32 with both ends supported by the support portions 32 </ b> B and 32 </ b> B of the main body frame 32. The feeding shaft 36 is disposed in parallel with the head 10. The web 34 wound in a roll shape is mounted on the feeding shaft 36 by mounting the core portion on the feeding shaft 36.

  The take-up shaft 38 is formed in a round bar shape, and both ends thereof are supported by the support portions 32 </ b> B and 32 </ b> B of the main body frame 32 and attached to the main body frame 32. The winding shaft 38 is disposed below the feeding shaft 36 and is disposed in parallel with the head 10. A winding core for winding the web 34 is attached to the winding shaft 38.

  The pressing roller 40 is composed of a rubber roller, and is attached to the main body frame 32 with both ends supported by the support portions 32 </ b> B and 32 </ b> B of the main body frame 32. The pressing roller 40 is disposed in front of the feeding shaft 36 and the winding shaft 38 (on the head side), and is disposed in parallel with the head 10. The web 34 is pressed against the nozzle surface 12 of the head 10 by the pressing roller 40.

  The first guide roller 42 and the second guide roller 44 are arranged above and below the pressure roller 40 and guide the travel of the web 34 so that the web 34 is wound around the pressure roller 40 at a predetermined angle.

  Here, the first guide roller 42 disposed above the pressing roller 40 guides the web 34 so that the web 34 wound around the pressing roller 40 travels obliquely downward toward the pressing roller 40.

  On the other hand, the second guide roller 44 disposed below the pressure roller 40 guides the web 34 so that the web 34 wound around the pressure roller 40 travels obliquely downward from the pressure roller 40.

  The web drive motor 46 is attached to the support portion 32B on one side of the main body frame 32 via a bracket. The web drive motor 46 is disposed coaxially with the take-up shaft 38 and is connected to the take-up shaft 38. By driving the web drive motor 46, the take-up shaft 38 rotates and the web 34 is taken up by the take-up shaft 38. The web 34 travels by winding the web 34 around the winding shaft 38.

  The cleaning liquid application device 48 applies a cleaning liquid to which ultrasonic waves are applied to the web 34 wound around the pressing roller 40. The cleaning liquid applying device 48 mainly includes a cleaning liquid supply nozzle 52, a cleaning liquid supply tank 54, a cleaning liquid supply pipe 56, a cleaning liquid supply pump 58, a cleaning liquid supply valve 60, and an ultrasonic transducer 62.

  The cleaning liquid supply nozzle 52 is formed corresponding to the width of the web 34. The cleaning liquid supply nozzle 52 is disposed above the web 34 that travels between the first guide roller 42 and the pressing roller 40, and faces the web 34 that travels between the first guide roller 42 and the pressing roller 40. The cleaning liquid is spouted from the spout. The spout is formed in a slit shape and is disposed orthogonal to the traveling direction of the web 34.

  The cleaning liquid supply tank 54 stores the cleaning liquid ejected from the cleaning liquid supply nozzle 52.

  The cleaning liquid supply pipe 56 connects the cleaning liquid supply tank 54 and the cleaning liquid supply nozzle 52 so that the cleaning liquid stored in the cleaning liquid supply tank 54 is supplied to the cleaning liquid supply nozzle 52.

  The cleaning liquid supply pump 58 is provided in the middle of the cleaning liquid supply pipe 56 and sends the cleaning liquid stored in the cleaning liquid supply tank 54 to the cleaning liquid supply nozzle 52.

  The cleaning liquid supply valve 60 is provided in the middle of the cleaning liquid supply pipe 56 and opens and closes the pipe of the cleaning liquid supply pipe 56.

  As shown in FIG. 5, the ultrasonic vibrator 62 is installed inside the cleaning liquid supply nozzle 52, and applies (excites) ultrasonic waves to the cleaning liquid ejected from the ejection port 52 </ b> A of the cleaning liquid supply nozzle 52. For example, the ultrasonic vibrator 62 applies ultrasonic waves of 400 kHz or higher to the cleaning liquid. Thereby, fine dirt can be efficiently peeled and dissolved. Further, even when the nozzle surface 12 is subjected to a liquid repellent treatment or the like, dirt can be removed without destroying the liquid repellent film.

  In the cleaning liquid applying device 48 configured as described above, the cleaning liquid is ejected from the cleaning liquid supply nozzle 52 by opening the cleaning liquid supply valve 60 and driving the cleaning liquid supply pump 58. Further, by driving the ultrasonic vibrator 62, ultrasonic waves are applied to the cleaning liquid ejected from the cleaning liquid supply nozzle 52.

  The cleaning liquid ejected from the cleaning liquid supply nozzle 52 is applied to the web 34 that runs between the first guide roller 42 and the pressing roller 40. Since the web 34 traveling between the first guide roller 42 and the pressure roller 40 travels obliquely downward toward the pressure roller 40, the cleaning liquid applied to the web 34 flows toward the pressure roller 40. Thereby, the cleaning liquid can be efficiently applied to the nozzle surface 12 at the time of wiping.

  The advance / retreat drive mechanism 50 moves the main body frame 32 forward and backward toward the nozzle surface 12 of the head 10 located at the cleaning position. The advance / retreat drive mechanism 50 is constituted by a cylinder, for example, and is fixed to a frame (not shown) of the ink jet recording apparatus. The main body frame 32 is driven by the advance / retreat drive mechanism 50 and moves between the contact position and the separation position. When the main body frame 32 moves to the contact position, the pressing roller 40 contacts the nozzle surface 12 of the head 10 at the head cleaning position. Further, when the main body frame 32 moves to the separation position, the pressing roller 40 separates (withdraws) from the nozzle surface 12 of the head 10 located at the head cleaning position.

  The overall operation of the ink jet recording apparatus including the head cleaning apparatus 30A is controlled by a control device (not shown). The control device is composed of, for example, a microcomputer, and executes a predetermined control program to perform image recording processing, head 10 cleaning processing, and the like.

[Action]
Next, the cleaning operation of the head 10 by the head cleaning device 30A of the present embodiment will be described.

  The cleaning of the head 10 is automatically executed according to the cleaning execution command from the operator, or according to the elapsed time from the previous cleaning, the number of printed sheets, and the like.

  First, the head 10 moves to the cleaning position. FIG. 6A shows a state (initial state) when the head 10 is moved to the cleaning position.

  In the initial state, the main body frame 32 of the head cleaning device 30A is located at the separated position. The head 10 is positioned above the pressure roller 40 provided in the head cleaning device 30A (initial position).

  When the head 10 moves to the cleaning position, the main body frame 32 of the head cleaning device 30A moves to the contact position.

  When the main body frame 32 moves to the contact position, the web drive motor 46 is driven, and the web 34 starts to travel. In addition, the cleaning liquid supply valve 60 is opened, and the cleaning liquid supply pump 58 is driven so that the cleaning liquid is ejected from the cleaning liquid supply nozzle 52. Further, the ultrasonic vibrator 62 is driven, and ultrasonic waves are applied to the cleaning liquid ejected from the cleaning liquid supply nozzle 52. Thereby, the cleaning liquid to which ultrasonic waves are applied is applied to the traveling web 34. Here, the cleaning liquid is applied in such an amount that it penetrates the web 34. In addition, ultrasonic waves of 400 kHz or higher are applied.

  Next, the head 10 moves downward. When the head 10 moves downward, the pressing roller 40 comes into contact with the nozzle surface 12 of the head 10 as shown in FIGS. Since the web 34 is wound around the pressing roller 40, the nozzle surface 12 of the head 10 moves downward while contacting the web 34. As a result, the nozzle surface 12 of the head 10 is wiped by the web 34.

  As described above, the cleaning liquid ejected from the cleaning liquid supply nozzle 52 is applied to the web 34. An ultrasonic wave is applied to the cleaning liquid by the ultrasonic vibrator 62. This ultrasonic wave propagates to the nozzle surface 12 through the cleaning liquid that has penetrated the web 34. Accordingly, dirt (particularly fine dirt) attached to the nozzle surface 12 can be peeled and dissolved, and the dirt on the nozzle surface 12 can be effectively removed (by vibration acceleration of fluid molecules constituting the cleaning liquid). Cleaning is improved.)

  The web 34 is running. For this reason, the nozzle surface 12 is always wiped with the clean web 34. Thereby, it is possible to always ensure a certain cleaning performance.

  The head 10 is lowered until the upper end portion of the nozzle surface 12 passes through the pressing roller 40. In the head 10, when the upper end portion of the nozzle surface 12 passes through the pressing roller 40, the lowering of the head 10 stops. Simultaneously with the stop of the head 10, the travel of the web 34 is stopped, and the application of the cleaning liquid and the application of ultrasonic waves are stopped.

  Thereafter, as shown in FIG. 6D, in the head cleaning device 30A, the main body frame 32 moves to the separation position.

  When the main body frame 32 moves to the separated position, the head 10 rises and returns to the initial position. Then, it moves in the horizontal direction and returns to the image recording position.

  The cleaning operation of the head 10 is completed through the series of steps described above.

  As described above, the head cleaning device 30 </ b> A according to the present embodiment wipes the nozzle surface 12 of the head 10 with the web 34 while applying the cleaning liquid to which the ultrasonic wave is applied to the web 34. Thereby, dirt (particularly fine dirt) adhering to the nozzle surface 12 of the head 10 can be efficiently removed. Moreover, by running the web 34, the nozzle surface 12 can be wiped off with the clean web 34 at all times, and the stable cleaning performance can be maintained.

  In the above example, the nozzle surface 12 is wiped only once, but may be wiped a plurality of times. In this case, the nozzle face 12 is wiped a plurality of times by moving the head 10 up and down (reciprocating) a plurality of times.

  In wiping, the head 10 preferably has a positive pressure in the nozzle. Thereby, it is possible to prevent the cleaning liquid from being drawn into the nozzle.

[Second Embodiment]
[Constitution]
FIG. 7 is a side cross-sectional view of the second embodiment of the head cleaning device. FIG. 8 is a front view of the second embodiment of the head cleaning device.

  As shown in the figure, the head cleaning device 30 </ b> B of the present embodiment includes a collection tray 70 that collects the cleaning liquid dropped from the web 34.

  Since the recovery tray 70 is the same as the head cleaning device 30A of the first embodiment except that the recovery tray 70 is provided, only the recovery tray 70 will be described here.

  The collection tray 70 is installed in the lower part of the main body frame 32 and collects the cleaning liquid dripped from the web 34. Therefore, the cleaning liquid dripped from the web 34 is formed in a size that can be recovered. For example, it is formed in a rectangular dish shape with an upper portion opened, and is disposed so as to surround the main body frame 32 and the lower portion of the head 10 located at the cleaning position.

  The collection dish 70 is connected to a waste liquid tank (not shown) via a cleaning liquid collection pipe (not shown). Therefore, the cleaning liquid recovered by the recovery tray 70 is recovered in the waste liquid tank.

[Action]
Next, the cleaning operation of the head 10 by the head cleaning device 30B of the present embodiment will be described.

  In the head cleaning device 30 </ b> B of the present embodiment, the nozzle surface 12 is cleaned by applying a cleaning liquid of a saturation amount or more to the web 34. In this way, by cleaning the nozzle surface 12 by applying a cleaning liquid of a saturation amount or more to the web 34, a film of the cleaning liquid can be formed on the web 34 wound around the pressing roller 40 and contact the nozzle surface 12. The amount of cleaning liquid and the contact time can be increased. Thereby, the cleaning effect by an ultrasonic wave can be improved.

  As in the first embodiment, first, the head 10 moves to the cleaning position.

  When the head 10 moves to the cleaning position, the main body frame 32 moves to the contact position.

  When the main body frame 32 moves to the contact position, the web drive motor 46 is driven, and the web 34 starts to travel. In addition, the cleaning liquid supply valve 60 is opened, and the cleaning liquid supply pump 58 is driven so that the cleaning liquid is ejected from the cleaning liquid supply nozzle 52. Further, the ultrasonic vibrator 62 is driven, and ultrasonic waves are applied to the cleaning liquid ejected from the cleaning liquid supply nozzle 52. Thereby, the cleaning liquid to which ultrasonic waves are applied is applied to the traveling web 34.

  Here, as described above, the web 34 is provided with a cleaning liquid of a saturation amount or more (a cleaning liquid having an amount exceeding the absorption capacity of the web 34). Thereby, a film of the cleaning liquid is formed on the surface of the web 34. At this time, in the head cleaning device 30B of the present embodiment, since the cleaning liquid is applied to the web 34 that runs downward toward the pressing roller 40, the applied cleaning liquid can be efficiently guided to the pressing roller 40.

  Note that, as in the first embodiment, an ultrasonic wave of 400 kHz or higher is applied as the ultrasonic wave.

  Next, the head 10 moves downward. When the head 10 moves downward, the pressing roller 40 contacts the nozzle surface 12 of the head 10. Since the web 34 is wound around the pressing roller 40, the nozzle surface 12 of the head 10 moves downward while contacting the web 34. As a result, the nozzle surface 12 of the head 10 is wiped by the web 34.

  As described above, the cleaning liquid ejected from the cleaning liquid supply nozzle 52 is applied to the web 34. An ultrasonic wave is applied to the cleaning liquid by the ultrasonic vibrator 62. This ultrasonic wave propagates to the nozzle surface 12 through the cleaning liquid that has penetrated the web 34. Thereby, the stain | pollution | contamination adhering to the nozzle surface 12 can be peeled and melt | dissolved, and the stain | pollution | contamination of the nozzle surface 12 can be removed effectively. In particular, in the present embodiment, a cleaning liquid having a saturation amount or more is applied to the web 34, a film of the cleaning liquid is formed on the surface of the web 34, and the nozzle surface 12 is wiped off. can do. That is, by forming a film of cleaning liquid on the surface of the web 34 wound around the pressing roller 40, the amount of cleaning liquid that contacts the nozzle surface 12 and the contact time can be increased, and the cleaning effect by ultrasonic waves can be enhanced. it can.

  The web 34 is running. For this reason, the nozzle surface 12 is always wiped with the clean web 34. Thereby, it is possible to always ensure a certain cleaning performance.

  Note that the cleaning liquid is dropped from the web 34 by applying a cleaning liquid of a saturation amount or more to the web 34, and the dropped cleaning liquid is collected by the collection dish 70. Thereby, contamination to the surroundings can be prevented.

  The head 10 is lowered until the upper end portion of the nozzle surface 12 passes through the pressing roller 40. In the head 10, when the upper end portion of the nozzle surface 12 passes through the pressing roller 40, the lowering of the head 10 stops. Simultaneously with the stop of the head 10, the travel of the web 34 is stopped, and the application of the cleaning liquid and the application of ultrasonic waves are stopped.

  Thereafter, the main body frame 32 moves to the separated position. When the main body frame 32 moves to the separated position, the head 10 rises and returns to the initial position. Then, it moves in the horizontal direction and returns to the image recording position.

  The cleaning operation of the head 10 is completed through the series of steps described above.

  As described above, the head cleaning device according to the present embodiment wipes the nozzle surface 12 of the head 10 with the web 34 while applying the cleaning liquid to which the ultrasonic wave is applied to the web 34. At this time, a cleaning liquid having a saturation amount or more is applied to the web 34. As a result, the amount of cleaning liquid that contacts the nozzle surface 12 and the contact time can be increased, and dirt (particularly fine dirt) adhering to the nozzle surface 12 of the head 10 can be efficiently removed. In this case, the cleaning liquid may be dripped from the web 34, but the cleaning liquid dripped from the web 34 is collected by the collection dish 70, so that the surroundings are not contaminated.

  The application amount of the cleaning liquid is not less than the saturation amount of the web 34, but if it is applied too much, the amount of dripping from the web 34 increases, so that the film can be formed on the web 34 and is necessary. It is preferable to apply with a minimum application amount.

  Further, in order to increase the amount of contact and the contact time of the cleaning liquid with the nozzle surface 12, it is possible to wipe off while forming a liquid pool between the nozzle surface 12 and the pressure roller 40 in contact with the nozzle surface 12. preferable. The liquid pool is formed as follows, for example.

  That is, when the head 10 is moved downward from the initial position and the pressing roller 40 is brought into contact with the nozzle surface 12 of the head 10, the lower end portion of the nozzle surface 12 is positioned at the pressing roller 40 as shown in FIG. At the same time, the descent of the head 10 is stopped. By applying the cleaning liquid to the web 34 in this state, the cleaning liquid accumulates between the pressure roller 40 in contact with the nozzle surface 12 and the nozzle surface 12 (the valley formed between the pressure roller 40 and the nozzle surface 12). The cleaning liquid is accumulated in the portion), and a liquid reservoir is formed. By lowering the head 10 in this state, as shown in FIG. 9B, the formed liquid pool can be maintained and the nozzle surface 12 can be wiped off.

  Thus, by wiping while forming a liquid pool between the nozzle surface 12 and the pressure roller 40, the contact time and the contact amount of the cleaning liquid can be further increased, and the cleaning effect by ultrasonic waves is further enhanced. Can do.

  In the case where the liquid pool is formed and wiped off as described above, it is preferable to form flange portions with enlarged diameters at both ends of the pressing roller 40, for example. Thereby, it is possible to prevent the cleaning liquid from leaking from both end portions of the pressing roller 40.

  In the above example, the nozzle surface 12 is wiped only once, but may be wiped a plurality of times. In this case, the nozzle face 12 is wiped a plurality of times by moving the head 10 up and down (reciprocating) a plurality of times. Further, in this case, it is preferable to wipe each time by changing the application amount of the cleaning liquid. In particular, at least one of a plurality of times is preferably applied with a saturating amount of cleaning liquid or more and wiped, and at least the last time is preferably applied with a given amount of cleaning liquid that penetrates the web and wiped. . Thereby, dirt can be effectively wiped off without causing unwiping. That is, at least once, by applying and wiping the cleaning liquid in an application amount equal to or greater than the saturation amount, the cleaning effect by ultrasonic waves can be increased and wiping can be performed. By applying the cleaning liquid in the applied amount and wiping it, it is possible to effectively prevent unwiping from occurring.

  In the case of wiping a plurality of times, when the head 10 is moved downward, the web 34 is wiped by applying a cleaning liquid of a saturated amount or more, and when moved upward, the web 34 penetrates the web 34. It is preferable to wipe by applying a cleaning liquid in an applied amount. Thereby, dirt can be effectively wiped off without causing unwiping.

  FIG. 10 is a flowchart showing a processing procedure when the nozzle surface 12 is wiped a plurality of times.

  In the initial state, as shown in FIG. 11A, the main body frame 32 is located at the separated position. The head 10 is located above the pressing roller 40.

  First, the main body frame 32 moves from the separated position to the contact position (step S10).

  Next, the web drive motor 46 is driven, and the web 34 starts to travel (step S11). Next, the cleaning liquid supply valve 60 is opened, the cleaning liquid supply pump 58 is driven, and the cleaning liquid is ejected from the cleaning liquid supply nozzle 52. Thereby, the cleaning liquid is applied to the web 34 (step S12). At this time, the cleaning liquid is applied to the web 34 in an application amount equal to or greater than the saturation amount. Next, the ultrasonic vibrator 62 is driven, and ultrasonic waves are applied to the cleaning liquid ejected from the cleaning liquid supply nozzle 52 (step S13). Thereby, the cleaning liquid to which ultrasonic waves are applied is applied to the traveling web 34.

  Next, the head 10 moves downward (step S14). When the head 10 moves downward, as shown in FIGS. 11B and 11C, the pressing roller 40 comes into contact with the nozzle surface 12 of the head 10. Since the web 34 is wound around the pressing roller 40, the nozzle surface 12 of the head 10 moves downward while contacting the web 34. As a result, the nozzle surface 12 of the head 10 is wiped by the web 34.

  Here, since the cleaning liquid of the saturation amount or more is given to the web 34, the cleaning effect by ultrasonic waves can be enhanced and wiped off.

  The head 10 is lowered until the upper end portion of the nozzle surface 12 passes through the pressing roller 40. The control device determines whether or not the upper end portion of the nozzle surface 12 has passed through the pressing roller 40 (step S15).

  When the upper end of the nozzle surface 12 passes through the pressing roller 40, the head 10 stops descending (step S16). Then, the application amount of the cleaning liquid is switched, and the cleaning liquid is applied with an application amount that penetrates the web 34 (step S17).

  Thereafter, the head 10 moves upward (step S18). When the head 10 moves upward, the pressing roller 40 comes into contact with the nozzle surface 12 of the head 10 as shown in FIGS. Since the web 34 is wound around the pressing roller 40, the nozzle surface 12 of the head 10 moves upward while contacting the web 34. As a result, the nozzle surface 12 of the head 10 is wiped by the web 34.

  Here, since the cleaning liquid is applied to the web 34 in such an amount that it can permeate, the nozzle surface 12 can be wiped without causing wiping.

  The head 10 moves up until the lower end portion of the nozzle surface 12 passes through the pressing roller 40. The control device determines whether or not the lower end portion of the nozzle surface 12 has passed the pressing roller 40 (step S19).

  When the upper end portion of the nozzle surface 12 passes the pressing roller 40, the head 10 stops rising at the initial position (step S20).

  When the movement of the head 10 is stopped, the supply of the cleaning liquid is stopped (step S21), and the application of ultrasonic waves is stopped (step S22). Further, the travel of the web 34 is stopped (step S23).

  Thereafter, as shown in FIG. 11F, the main body frame 32 moves to the separated position.

  The cleaning operation of the head 10 is completed through the series of steps described above.

  As described above, when the head 10 is wiped a plurality of times, when the head 10 is moved downward, the web 34 is wiped with a cleaning liquid of a saturated amount or more, and when the head 10 is moved upward, the web 34 By applying and wiping the cleaning liquid in such an amount that it can penetrate into the surface, the dirt can be effectively wiped off without causing unwiping.

  In the above example, the head 10 is reciprocated once and the nozzle surface 12 is wiped. However, the head 10 can be reciprocated a plurality of times to wipe the nozzle surface 12. Further, when the head 10 is reciprocated a plurality of times, the cleaning liquid can be applied and wiped off at an application amount that penetrates the web 34 only once (at the time of ascent).

[Third Embodiment]
FIG. 12 is a side cross-sectional view of the third embodiment of the head cleaning device.

  As shown in the figure, the head cleaning device 30C according to the present embodiment targets the horizontally installed head 10 as a cleaning target.

  The nozzle surface 12 is arrange | positioned horizontally at the head 10 toward the downward direction. The head cleaning device 30C wipes the nozzle surface 12 by bringing the pressing roller 40 into contact with the nozzle surface 12 from below.

  In this case, the cleaning liquid supply nozzle 52 is installed so as to eject the cleaning liquid toward the contact portion between the pressing roller 40 and the nozzle surface 12. Thereby, the nozzle surface 12 can be wiped with the web 34, giving the cleaning effect by an ultrasonic wave.

[Other Embodiments]
In the above embodiment, the nozzle side is wiped by moving the head side, but the nozzle surface can also be wiped by moving the head cleaning device side. Further, the nozzle surface can be wiped by moving both the head and the head cleaning device.

  In the above embodiment, the head is moved in the direction orthogonal to the width direction (nozzle row direction) to wipe the nozzle surface. However, the head is moved in the width direction to wipe. You can also.

  In the above series of embodiments, the case of cleaning the line head has been described as an example. However, the present invention can also be applied to the case of cleaning a so-called shuttle head.

  Moreover, although the inkjet recording apparatus of the said embodiment demonstrated the case where this invention was applied to the inkjet recording apparatus which records an image on roll paper as an example, this invention is the inkjet recording which records an image on a sheet of paper. The same applies to the device.

  In the above embodiment, the case where the ultrasonic vibrator is installed in the cleaning liquid supply nozzle has been described as an example. However, the installation position of the ultrasonic vibrator is not limited to this. For example, it can be installed in the pipe of the cleaning liquid supply pipe.

  DESCRIPTION OF SYMBOLS 10 ... Head (inkjet head), 12 ... Nozzle surface, 14 ... Nozzle, 16 ... Head mount, 20 ... Guide roller, 30A, 30B, 30C ... Head cleaning device, 32 ... Body frame, 32A ... Body part, 32B ... Support 34, web, 36, feeding shaft, 38 ... take-up shaft, 40 ... pressing roller, 42 ... first guide roller, 44 ... second guide roller, 46 ... web drive motor, 48 ... cleaning liquid applicator, 50 ... Advancing / retreating drive mechanism, 52 ... cleaning liquid supply nozzle, 52A ... jet, 54 ... cleaning liquid supply tank, 56 ... cleaning liquid supply pipe, 58 ... cleaning liquid supply pump, 60 ... cleaning liquid supply valve, 62 ... ultrasonic vibrator, 70 ... collection dish , M ... Media

Claims (11)

In a head cleaning device for cleaning the nozzle surface of an inkjet head,
A pressing roller that is pressed against the nozzle surface;
A web wound around the pressing roller;
A feeding shaft for feeding out the web;
A winding shaft for winding the web;
A guide member that guides the web that is fed from the feed shaft and wound on the take-up shaft to be wound around the pressing roller;
Web driving means for running the web;
Cleaning liquid application means for applying a cleaning liquid to the web wound around the pressing roller;
An ultrasonic generator for applying ultrasonic waves to the cleaning liquid;
A head cleaning device comprising: In the inkjet head, the nozzle surface is arranged substantially vertically,
The pressing roller is disposed horizontally and parallel to the nozzle surface,
The guide member guides the web so as to run obliquely downward toward the pressing roller, or to run obliquely upward from the pressing roller,
The cleaning liquid applying unit applies the cleaning liquid from above the web to a part where the web runs obliquely downward toward the pressing roller or a part where the web runs obliquely upward from the pressing roller. The head cleaning device according to claim 1, wherein:   The head cleaning device according to claim 2, wherein the cleaning liquid applying unit applies the cleaning liquid at a saturation amount or more to the web so that a film of the cleaning liquid is formed on a surface of the web.   The head cleaning device according to claim 3, further comprising a collection dish for collecting the cleaning liquid dripping from the web. The cleaning liquid applying means applies the cleaning liquid from a nozzle,
5. The head cleaning device according to claim 1, wherein the ultrasonic wave generation unit is installed in the nozzle and applies the ultrasonic wave to the cleaning liquid in the nozzle. 6. An inkjet head cleaning method using the head cleaning device according to claim 3,
While applying the cleaning liquid to which the ultrasonic wave has been applied to the web, the web is run, the pressure roller is brought into contact with the nozzle surface, and the pressure roller and the nozzle surface are relatively moved in the vertical direction. In the head cleaning method of moving the nozzle surface and wiping the nozzle surface with the web,
The nozzle surface is wiped with the web by relatively moving the pressure roller and the nozzle surface in the vertical direction in a state where a pool of the cleaning liquid is formed between the nozzle surface and the pressure roller. A head cleaning method. An inkjet head cleaning method using the head cleaning device according to claim 2,
While applying the cleaning liquid to which the ultrasonic wave has been applied to the web, the web is run, the pressure roller is brought into contact with the nozzle surface, and the pressure roller and the nozzle surface are relatively moved in the vertical direction. In the head cleaning method of moving the nozzle surface and wiping the nozzle surface with the web,
The nozzle is moved by moving the pressing roller and the nozzle surface a plurality of times relatively in the vertical direction, and the nozzle surface is wiped with the web, and at least once, the cleaning liquid having a saturation amount or more is applied to the web. A head cleaning method comprising wiping the surface and wiping the nozzle surface by applying the cleaning liquid in an application amount sufficient to penetrate the web at least once. An inkjet head cleaning method using the head cleaning device according to claim 2,
While applying the cleaning liquid to which the ultrasonic wave has been applied to the web, the web is run, the pressure roller is brought into contact with the nozzle surface, and the pressure roller and the nozzle surface are relatively moved in the vertical direction. In the head cleaning method in which the nozzle surface is wiped with the web by reciprocating
When the pressing roller moves relatively downward with respect to the nozzle surface, the cleaning liquid of a saturation amount or more is applied to the web to wipe the nozzle surface, and the pressing roller moves against the nozzle surface. When the head moves relatively upward, the cleaning liquid is applied in an application amount that penetrates the web, and the nozzle surface is wiped off.   9. The head cleaning method according to claim 6, wherein the nozzle surface is wiped off by setting the pressure in the nozzle of the ink jet head to a positive pressure. 10.   The head cleaning method according to claim 6, wherein the ultrasonic wave having a frequency of 400 kHz or more is applied to the cleaning liquid.   An ink jet recording apparatus comprising the head cleaning apparatus according to claim 1.

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