Recording head recovery method

A method for recovery of a recording head includes cleaning liquid supplying operation, wiping operation, and backflow operation. The recording head is connected to a cleaning liquid tank for storing cleaning liquid via a cleaning liquid supplying path. In the backflow operation, a liquid supply mechanism makes the cleaning liquid in the cleaning liquid supplying path to flow backward in a direction pointing from the cleaning liquid supplying openings to the cleaning liquid tank. The recording head includes an ink ejection region in which ink ejection openings are open, and a cleaning liquid supplying region which is arranged upstream of the ink ejection region in a wiping direction and in which cleaning liquid supplying openings are open. The backflow operation is performed after a wiper passes the cleaning liquid supplying region and before the wiper reaches the ink ejection region.

TECHNICAL FIELD

The present invention relates to a recovery system for a recording head having ink ejection openings for ejecting ink on a recording medium such as a sheet, to an ink-jet recording apparatus provided with such a recording head recovery system, and to a recording head recovery method.

BACKGROUND ART

As recording apparatuses such as facsimile machines, copiers, and printers, ink-jet recording apparatuses, which form images by ejecting ink, are widely used for their ability to form high-definition images.

In such ink-jet recording apparatuses, fine ink droplets (hereinafter, referred to as mist) which are ejected together with ink droplets for image recording, and splashed mist which is generated when ink droplets attach to the recording medium, attach to and solidify on an ink ejection face of a recording head. As mist on the ink ejection face gradually increases and covers the ink ejection openings, it causes, for example, degraded straightness of the ink trajectory (curved flight) or ejection failure, and leads to degraded printing performance of the recording head.

To avoid that, in one known ink-jet recording apparatus, for cleaning the ink ejection face of the recording head, a plurality of cleaning liquid supplying openings are provided in a part of the ink ejection face outside an ink ejection region (upstream in the direction of wiping by a wiper) in which a plurality of ink ejection openings are open. In such an ink-jet recording apparatus, after the cleaning liquid is supplied from the cleaning liquid supplying openings, the wiper can be moved along the ink ejection face starting outward of the cleaning liquid supplying openings so that the wiper wipes the ink ejection face while holding the cleaning liquid. In this way, recovery operation for the recording head is performed.

An ink-jet recording apparatus provided with a plurality of cleaning liquid supplying openings on the ink ejection face of the recording head is disclosed, for example, in Patent Document 1 identified below.

LIST OF CITATIONS

Patent Literature

SUMMARY OF THE INVENTION

Problem to be Solved by the Invention

However, in the conventional ink-jet recording apparatus mentioned above, after recovery processing for the recording head is performed, the cleaning liquid may be left around a cleaning liquid supplying opening. Inconveniently, in this case, when a recording medium touches the recording head, the cleaning liquid may attach to and soil the recording medium, or the cleaning liquid may drop and attach to a conveying belt and the like and soil the inside of the device.

The present invention has been made to solve the above problem. An object of the present invention is to provide a recording head recovery system which is configured to clean the ink ejection face while preventing the cleaning liquid from attaching to a recording medium or dropping, an ink-jet recording apparatus provided with such a recording head recovery system, and a recording head recovery method.

Means for Solving the Problem

According to one aspect of what is disclosed herein, a recording head recovery system comprises a recording head which includes an ink ejection face in which a plurality of ink ejection openings for ejecting ink on a recording medium are open, and a plurality of cleaning liquid supplying openings for supplying cleaning liquid which are arranged upstream of the ink ejection openings in a wiping direction in which a wiper wipes the ink ejection face; a cleaning liquid tank for storing the cleaning liquid to be supplied to the cleaning liquid supplying openings in the recording head; a cleaning liquid supplying path which connects together the cleaning liquid tank and the recording head; a liquid supply mechanism which is provided in the cleaning liquid supplying path and which includes a liquid supplying pump for supplying the cleaning liquid in the cleaning liquid tank to the recording head; and a controller which controls operation of the liquid supply mechanism. The controller is configured to perform the recording head recovery operation including cleaning liquid supplying operation for supplying the cleaning liquid from the cleaning liquid supplying openings by making the liquid supply mechanism supply the cleaning liquid in the cleaning liquid tank to the recording head via the cleaning liquid supplying path, wiping operation for wiping the ink ejection face while the wiper retains the cleaning liquid after performing the cleaning liquid supplying operation, and backflow operation for controlling the liquid supply mechanism to make the cleaning liquid in the cleaning liquid supplying path to flow backward in a direction pointing from the cleaning liquid supplying openings to the cleaning liquid tank while or after the wiping operation is performed.

Advantageous Effects of the Invention

With a recording head recovery system according to a first aspect of the present invention, recording head recovery operation including cleaning liquid supplying operation for supplying cleaning liquid from cleaning liquid supplying openings and wiping operation for wiping an ink ejection face while a wiper retains the cleaning liquid can be performed. With this, the ink ejection face can be cleaned.

Moreover, a liquid supply mechanism can perform backflow operation in which the cleaning liquid in the cleaning liquid supplying path is made to flow backward in the direction pointing from a cleaning liquid supplying openings to a cleaning liquid tank. This makes it possible to prevent the cleaning liquid to be left around the cleaning liquid supplying openings after recovery processing for the recording head is performed. This helps prevent, even if a recording medium touches the recording head, the cleaning liquid from attaching to and soiling the recording medium. This also helps prevent the cleaning liquid from dropping from the cleaning liquid supplying openings, and thus it is possible to prevent the cleaning liquid from attaching to a sheet conveying belt and the like and soiling the inside of the device.

This and other objects of the present invention, and the specific benefits obtained according to the present invention, will become apparent from the description of embodiments which follows.

DESCRIPTION OF EMBODIMENTS

As shown inFIG. 1, in an ink-jet recording apparatus100according to one embodiment of the present invention, in a left-side part, a sheet feeding tray2which houses sheets S (a recording medium) is provided. At one end part of the sheet feeding tray2, there are provided a sheet feeding roller3that coveys and feeds the housed sheets S one after another, starting with the top sheet S, to a first conveying unit5, which will be described later, and a driven roller4that is in pressed contact with the sheet feeding roller3to rotate by following it.

On the downstream side (right side inFIG. 1), in the sheet conveying direction (arrow X direction), of the sheet feeding roller3and the driven roller4, the first conveying unit5and a recording portion9are arranged. The first conveying unit5is configured to include a first driving roller6, a first driven roller7, and a first conveying belt8which is stretched between the first driving roller6and the first driven roller7. According to a control signal from a controller110which controls the whole ink-jet recording apparatus100, the first driving roller6is driven to rotate in the clockwise direction and thus a sheet S held on the first conveying belt8is conveyed in the arrow X direction.

The recording portion9includes a head housing10and line heads11C,11M,11Y and11K which are held on the head housing10. These line heads11C to11K are supported at such a height that a predetermined gap (for example, 1 mm) is formed relative to the conveying face of the first conveying belt8. As shown inFIG. 2, the line heads11C to11K each include one or more (here, one) recording heads17which extend in the sheet width direction (up-down direction inFIG. 2) perpendicular to the sheet conveying direction.

As shown inFIGS. 3 and 4, at an ink ejection face F1on a head portion18(ink ejection head portion) of the recording head17, there is provided an ink ejection region R1in which a number of ink ejection openings18a(seeFIG. 2) are arrayed. The diameter of each ink ejection opening18ais set at, for example, 20 μm.

To the recording heads17each constituting either of the line heads11C to11K, ink of either of four colors (cyan, magenta, yellow, and black) corresponding to the color of each of the line heads11C to11K and each stored in an ink tank (unillustrated) for the corresponding color is supplied.

According to the control signal from the controller110(seeFIG. 1), and based on image data received from an external computer, each recording head17ejects ink from the ink ejection openings18atoward the sheet S which is conveyed while being held by absorption on the conveying face of the first conveying belt8. In this way, a color image having ink of four colors, namely cyan, magenta, yellow and black, overlaid together is formed on the sheet S on the first conveying belt8.

In the recording head17, a cleaning liquid supplying member (cleaning liquid supplying head portion)60for supplying a cleaning liquid is provided. The cleaning liquid supplying member60is arranged adjacent to the head portion18, on its upstream side (right side inFIG. 3) in the wiping direction of a wiper35, which will be described later. The cleaning liquid supplying member60has a cleaning liquid supplying face F2which includes a cleaning liquid supplying region R2on which a number of cleaning liquid supplying openings60a(seeFIG. 5) for supplying the cleaning liquid are arrayed. The diameter of each cleaning liquid supplying opening60ais set, for example, at 0.1 mm so as to be larger than that of each ink ejection opening18a. On the head portion18, at least the ink ejection face F1is formed of, for example, SUS (stainless steel). On the cleaning liquid supplying member60, at least the cleaning liquid supplying face F2is formed of, for example, SUS or resin.

The cleaning liquid supplying face F2is formed so as to be flush with the ink ejection face F1. In a part upstream (right-side inFIG. 3) of the cleaning liquid supplying face F2in the cleaning liquid supplying member60in the wiping direction, an inclined face62is formed.

As shown inFIG. 5, a plurality of cleaning liquid supplying openings60aare arranged with a predetermined pitch in the head width direction (arrow BB′ direction) perpendicular to the wiping direction (arrow A direction).FIG. 5only shows one row of a plurality of cleaning liquid supplying openings60awhich are arranged along the head width direction, but a plurality of such rows may be provided adjacent to each other in the wiping direction (arrow A direction).

As shown inFIG. 6, the cleaning liquid supplying openings60a(seeFIG. 5) in the cleaning liquid supplying member60are connected to a downstream end of a cleaning liquid supplying path70comprising a tube through which cleaning liquid23passes. An upstream end of the cleaning liquid supplying path70is connected to a subtank (cleaning liquid tank)71in which is stored the cleaning liquid23to be supplied to the cleaning liquid supplying member60. The upstream end of the cleaning liquid supplying path70is immersed in the cleaning liquid23. The cleaning liquid supplying path70is provided with a supplying pump (liquid supplying pump)72that pumps up the cleaning liquid23from the subtank71to feed it to the cleaning liquid supplying member60. In the diagram, the cleaning liquid23is indicated by hatching to facilitate understanding.

The subtank71is connected to a downstream end of a cleaning liquid replenishing path80comprising a tube through which the cleaning liquid23passes. An upstream end of the cleaning liquid replenishing path80is connected to a main tank81in which is stored the cleaning liquid23to be supplied to the subtank71. The upstream end of the cleaning liquid replenishing path80is immersed in the cleaning liquid23. The cleaning liquid replenishing path80is provided with a replenishing pump82that pumps up the cleaning liquid23from the main tank81to feed it to the subtank71. For the replenishing pump82, for example, a tube pump, a syringe pump, a diaphragm pump, or the like can be used. The detailed structure of and around the subtank71and the main tank81will be described later.

In this ink-jet recording apparatus100, to clean the ink ejection face F1on the recording head17, at the start of printing after a long out-of-operation period and during intermissions of printing operation, ink is discharged forcibly from the ink ejection openings18ain all the recording heads17. Then the cleaning liquid23is supplied through the cleaning liquid supplying openings60a(seeFIG. 5) in all the recording heads17to the cleaning liquid supplying region R2, and the ink ejection face F1is wiped with the wiper35, which will be described later, in preparation for the next printing operation.

As shown back inFIG. 1, on a downstream side (right side inFIG. 1) of the first conveying unit5in the sheet conveying direction, a second conveying unit12is arranged. The second conveying unit12is configured to include a second driving roller13, a second driven roller14, and a second conveying belt15which is stretched between the second driving roller13and the second driven roller14. The second driving roller13is driven to rotate in the clockwise direction and thus a sheet S held on the second conveying belt15is conveyed in the arrow X direction.

The sheet S with an ink image recorded on it at the recording portion9is conveyed to the second conveying unit12. While the sheet S passes through the second conveying unit12, the ink ejected on the surface of the sheet S is dried. Under the second conveying unit12, a wipe unit19and a cap unit90are arranged. When wiping operation is performed by the wiper35as mentioned above, the first conveying unit5descends. Then the wipe unit19moves to under the recording portion9, wipes off the ink discharged forcibly from the ink ejection openings18ain the recording head17and the cleaning liquid23supplied from the cleaning liquid supplying openings60a, and collects the ink and the cleaning liquid23that are wiped. When capping the ink ejection face F1(seeFIG. 3) on the recording head17, the first conveying unit5descends. Then the cap unit90horizontally moves to under the recording portion9, and then moves upward to be fitted to the lower face of the recording head17.

On the downstream side of the second conveying unit12in the sheet conveying direction, there is provided a discharge roller pair16which discharges the sheet S with an image recorded on it to outside the apparatus main body. On the downstream side of the discharge roller pair16, there is provided a discharge tray (unillustrated) on which the sheets S discharged outside the apparatus main body are stacked.

The wipe unit19includes a plurality of wipers35(seeFIG. 10) which are movable along the ink ejection face F1, a substantially rectangular carriage (unillustrated) on which the plurality of wipers35are fixed, and a supporting frame (unillustrated) which supports the carriage. The carriage (unillustrated) is supported so as to be slidable in the arrow AA′ direction relative to the supporting frame (unillustrated).

The wiper35is an elastic member (for example, a rubber member made of EPDM) for wiping the cleaning liquid23supplied from the cleaning liquid supplying openings60a(seeFIG. 5) in each recording head17. The wiper35is kept in pressed contact with a part (here, the inclined face62) upstream of the cleaning liquid supplying region R2(seeFIG. 4) in the cleaning liquid supplying member60in the wiping direction. As the carriage (unillustrated) moves, the wiper35wipes the cleaning liquid supplying face F2and the ink ejection face F1in the predetermined direction (arrow A direction).

Next, the structures of and around the cleaning liquid supplying member60, the subtank71and the main tank81will be described in detail.

As shown inFIG. 6, at a predetermined position in the subtank71, a first detection sensor73for sensing the cleaning liquid23is provided. The first detection sensor73has an electrode pair (unillustrated) to which a voltage is applied and which is arranged inside the subtank71. The first detection sensor73can, based on whether a current is present between the electrodes, sense the presence or the absence of the cleaning liquid23. When the first detection sensor73senses the absence of the liquid (absence of the current), the cleaning liquid23is supplied by the replenishing pump82from the main tank81to the subtank71until the presence of the liquid (presence of the current) is sensed. In this way, the liquid level (top face) of the cleaning liquid23inside the subtank71is substantially kept constant.

In a lower part of the main tank81, a second detection sensor83for sensing the cleaning liquid23is provided. The second detection sensor83has an electrode pair (unillustrated) to which a voltage is applied and which is arranged inside the main tank81. The second detection sensor83can, based on whether a current is present between the electrodes, sense the presence or the absence of the cleaning liquid23. When the second detection sensor83senses the absence of the liquid, and a display panel (unillustrated) of the ink-jet recording apparatus100indicates that the main tank81has become empty. With this, a user or an operator replaces the main tank81with a new one, or replenishes the main tank81with the cleaning liquid23.

The subtank71is arranged above the main tank81and below the cleaning liquid supplying face F2of the recording head17. The subtank71is provided with an atmospheric open port71afor equalizing the pressure in its internal space with the atmospheric pressure.

As shown inFIG. 7, the cleaning liquid supplying path70includes a first supplying path70awhich connects together the subtank71and the supplying pump72and a second supplying path70bwhich connects together the supplying pump72and the cleaning liquid supplying member60of the recording head17. The first supplying path70ais provided with a first valve74awhich opens and closes the first supplying path70a. The second supplying path70bis provided with a second valve74bwhich opens and closes the second supplying path70b. The supplying pump72, the first valve74a, the second valve74band a pump driving mechanism50, which will be described later, constitute a liquid supply mechanism75for supplying the cleaning liquid23in the subtank71to the recording head17.

The supplying pump72is composed of a syringe pump having a cylinder72awhich is formed in a cylindrical shape and a piston72bwhich is inserted in the cylinder72aand which is reciprocatable in the axial direction of the cylinder. One end of the cylinder72a(lower end inFIG. 7) is provided with an inlet port to which the first supplying path70ais connected and an outflow port to which the second supplying path70bis connected. The other end of the cylinder72a(upper end inFIG. 7) is open and the piston72bis inserted in there.

The piston72bincludes a disk portion72cwhich slides on the inner circumferential face of the cylinder72aand a shaft portion72dwhich is fixed on the top face of the disk portion72cand extends to outside the cylinder72a. A plurality of rack teeth72eare formed on the shaft portion72d.

The rack teeth72eis engaged with a driving gear51. The driving gear51is connected to a drive motor53comprising a stepping motor via an intermediate gear52. The driving gear51, the intermediate gear52and the drive motor53constitute the pump driving mechanism50which drives the supplying pump72. When the drive motor53rotates forward (rotates in the counter-clockwise direction inFIG. 7), the piston72bmoves in the extraction direction (upward inFIG. 7) with respect to the cylinder72a, and the cleaning liquid23flows into the supplying pump72. When the drive motor53rotates backward (rotates in the clockwise direction inFIG. 7), the piston72bmoves in the insertion direction (downward inFIG. 7) with respect to the cylinder72a, and the cleaning liquid23in the supplying pump72flows out.

Next, recovery operation for the recording head17using the wipe unit19in the ink-jet recording apparatus100of this embodiment will be described. Recovery operation for the recording head17described below is performed by controlling the operation of the recording head17, the wipe unit19, the liquid supply mechanism75, and the like based on the control signal from the controller110(seeFIG. 1).

When recovery operation for the recording head17is performed, first, as shown inFIG. 8, the controller110(seeFIG. 1) lowers the first conveying unit5located under the recording portion9. The controller110then moves the wipe unit19arranged under the second conveying unit12horizontally to arrange it between the recording portion9and the first conveying unit5. In this state, the wiper35(seeFIG. 10) of the wipe unit19is arranged under the ink ejection face F1and the cleaning liquid supplying face F2(seeFIG. 10) of the recording head17. Here, as shown inFIG. 9, a meniscus of the cleaning liquid23is formed starting at the edge of the cleaning liquid supplying opening60aso as to curve inward of the recording head17. Moreover, the first valve74ais closed and the second valve74bis open.

Cleaning Liquid Supplying Operation:

Prior to wiping operation (which will be described later), the controller110(seeFIG. 1) supplies the cleaning liquid23to the recording head17as shown inFIG. 10. Specifically, the controller110closes the second valve74band then opens the first valve74a. Then, when the drive motor53rotates forward, the piston72bmoves in the extraction direction (upward inFIG. 7) with respect to the cylinder72a, and the cleaning liquid23flows into the supplying pump72via the first supplying path70a. Then, the controller110closes the first valve74aand then opens the second valve74b. When the drive motor53rotates backward, the piston72bmoves in the insertion direction (downward inFIG. 7) with respect to the cylinder72a, and the cleaning liquid23is supplied to the recording head17via the second supplying path70b. Here, the cleaning liquid23goes into the state shown inFIG. 11. That is, the cleaning liquid23is retained under the surface tension in a state overflowing around the cleaning liquid supplying opening60a.

Ink Pushing Out Operation:

Prior to wiping operation (which will be described later), the controller110(seeFIG. 1) supplies ink22to the recording head17as shown inFIG. 10. The supplied ink22is pushed (purged) forcibly out of the ink ejection openings18a. By this purging operation, thickened ink, foreign matter and air bubbles inside the ink ejection openings18aare discharged from the ink ejection openings18a. Here, the purged ink22is pushed out to the ink ejection face F1along the shape of the ink ejection region R1in which the ink ejection openings18alie. In the diagram, the ink (purged ink)22is indicated by hatching to facilitate understanding.

The controller110, as shown inFIG. 12, raises the wiper35so that the wiper35makes contact with the inclined face62of the cleaning liquid supplying member60of the recording head17with a predetermined pressure. Here, the wiper35is raised so that the top face of the wiper35is approximately 1 mm higher than the ink ejection face F1and the cleaning liquid supplying face F2. When the wiper35has just been raised, it does not need to be in pressed contact with the inclined face62. That is, the wiper35may be raised at a position further to the right inFIG. 12.

The controller110moves the wiper35from a state inFIG. 12in the direction toward the ink ejection region R1(arrow A direction) as shown inFIG. 13along the cleaning liquid supplying face F2. In this way, the wiper35scrapes off the cleaning liquid23that protrudes downward from the cleaning liquid supplying face F2(here, also a part of the cleaning liquid23inside the cleaning liquid supplying openings60ais moved to the wiper35side), and thereby the wiper35moves toward the ink ejection region R1while retaining the cleaning liquid23. Here, as shown inFIG. 14, the cleaning liquid23on the cleaning liquid supplying member60may be left around the cleaning liquid supplying openings60a.

As shown inFIG. 15, the wiper35, while keeping retaining the cleaning liquid23, moves on the ink ejection face F1leftward (in the arrow A direction). Here, ink droplets (waste ink) which have attached to the ink ejection face F1and solidified are dissolved by the cleaning liquid23and ink (purged ink)22and are wiped off by the wiper35. When the wiper35moves further leftward (in the arrow A direction) to reach a position at the side opposite to the cleaning liquid supplying region R2relative to the ink ejection region R1, the leftward movement is stopped. The cleaning liquid23and the waste ink wiped off by the wiper35are collected in a cleaning liquid collection tray (unillustrated) provided in the wipe unit19.

Here, in this embodiment, the controller110, during wiping operation, controls the liquid supply mechanism75to make the cleaning liquid23in the cleaning liquid supplying path70flow backward in the direction pointing from the cleaning liquid supplying openings60ato the subtank71. Specifically, the controller110, after the tip end of the wiper35passes the cleaning liquid supplying region R2and before it reaches the ink ejection region R1, makes the drive motor53rotate slightly forward with the first valve74aclosed and the second valve74bopen. As a result, the piston72bmoves several millimeters in the extraction direction with respect to the cylinder72a, and this causes the cleaning liquid23to flow backward in the direction pointing from the cleaning liquid supplying openings60ato the supplying pump72. This backflow operation causes the cleaning liquid23(seeFIG. 14) around the cleaning liquid supplying openings60ato be sucked into the cleaning liquid supplying openings60a, and as shown inFIG. 9, a meniscus of the cleaning liquid23is formed starting at the edge of the cleaning liquid supplying openings60aso as to curve inward of the recording head17.

After wiping operation, as shown inFIG. 16, the controller110lowers the wiper35to separate it from the ink ejection face F1.

Finally, the controller110moves the wipe unit19arranged between the recording portion9and the first conveying unit5horizontally to arrange it under the second conveying unit12, and raises the first conveying unit5up to a predetermined position. Recovery operation for the recording head17is thus finished.

In this embodiment, as mentioned above, cleaning liquid supplying operation in which the cleaning liquid23is supplied from the cleaning liquid supplying openings60aas well as wiping operation in which the wiper35wipes the ink ejection face F1while retaining the cleaning liquid23are performed. In this way, the ink ejection face F1can be cleaned.

Moreover, the liquid supply mechanism75performs backflow operation in which the cleaning liquid23in the cleaning liquid supplying path70is made to flow backward in the direction pointing from the cleaning liquid supplying openings60ato the subtank71. This makes it possible to prevent the cleaning liquid23from being left around the cleaning liquid supplying openings60aafter recovery processing for the recording head17is performed. This helps prevent, even if a sheet S touches the recording head17, the cleaning liquid23from attaching to and soiling the sheet S. This also helps prevent the cleaning liquid23from dropping from the cleaning liquid supplying openings60a, and thus it is possible to prevent the cleaning liquid23from attaching to the first conveying belt8and the like and soiling the inside of the device.

As mentioned above, the supplying pump72is a syringe pump having a cylinder72aand a piston72bwhich is inserted in the cylinder72aand which is reciprocatable. The amount of backflow of the cleaning liquid23can be thus controlled according to the moving distance of the piston72b, and this makes fine adjustment of the amount of backflow of the cleaning liquid23possible. This helps easily prevent too much of the cleaning liquid23from flowing backward. That is, a meniscus of the cleaning liquid23can be easily formed near the cleaning liquid supplying opening60a.

As mentioned above, during backflow operation, the piston72bis moved in the extraction direction with respect to the cylinder72awith the first valve74aclosed and the second valve74bopen. With this, the cleaning liquid23is made to flow backward easily.

As mentioned above, backflow operation causes a meniscus of the cleaning liquid23to form starting at the edge of the cleaning liquid supplying opening60aso as to curve inward of the recording head17. This allows an appropriate amount of cleaning liquid23to be easily supplied from the cleaning liquid supplying openings60aduring the next cleaning liquid supplying operation.

As mentioned above, backflow operation is performed after the wiper35passes the cleaning liquid supplying region R2and before it reaches the ink ejection region R1. This allows backflow operation to be performed right after (at the earliest timing after) the wiper35passes the cleaning liquid supplying region R2, and thus it is possible to reliably prevent the cleaning liquid23from dropping from the cleaning liquid supplying openings60a.

As mentioned above, the recording head17is composed of the head portion18having the ink ejection face F1and the cleaning liquid supplying head portion60having the cleaning liquid supplying face F2. This allows the path of the ink and the path of the cleaning liquid in the recording head17to be formed in different members (the head portion18and the cleaning liquid supplying head portion60), and thus it is possible to prevent the structure of the recording head17from becoming complicated.

The embodiments disclosed above should be understood to be in every aspect illustrative and not restrictive. The scope of the present invention is defined not by the description of the embodiments given above but by the appended claims, and should be understood to encompass any modifications made in the sense and scope equivalent to those of the claims.

For example, although the above embodiments deal with an example where the cleaning liquid supplying member60in which the cleaning liquid supplying openings60aare formed is provided separately from the head portion18, this is not meant to limit the present invention. Instead of the cleaning liquid supplying member60being provided, the cleaning liquid supplying openings60amay be formed in the head portion18. Here, as in the recording head17in a modified example according to the present invention shown inFIG. 17, the cleaning liquid supplying openings60amay be arranged adjacent to the ink ejection openings18a(for example, the ink ejection openings18aand the cleaning liquid supplying openings60amay be arranged alternately).

For another example, although the above embodiments deal with an example where a syringe pump is used as the supplying pump72, a pump other than the syringe pump, such as a tube pump or a diaphragm pump, may also be used as a supplying pump72.

For another example, although the above embodiments deal with an example where backflow operation is performed while wiping operation is performed, backflow operation may be performed after wiping operation is performed.

For another example, although the above embodiments deal with an example where backflow operation is performed using the supplying pump72, this is not meant to limit the present invention. For example, if the subtank71is arranged below the cleaning liquid supplying face F2of the recording head17, the first valve74aand the second valve74bof the liquid supply mechanism75may be opened so that a negative pressure is applied to the cleaning liquid23in the cleaning liquid supplying openings60ato cause the cleaning liquid23to flow backward.

Although the above embodiments deal with an example where recovery operation for the recording head17is performed using the cleaning liquid23and the ink (purged ink)22, recovery operation for the recording head17may be performed using only the cleaning liquid23. That is, ink pushing out operation does not necessarily need to be performed.

Any configurations achieved by combining the configurations of the embodiments and modified examples described above are also within the technical scope of the present invention.