JP2009051058A - Method for introducing liquid to liquid-droplet discharge head its practicable, liquid introduction apparatus, and its practicable liquid-droplet discharge recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the method for introducing a liquid to a liquid-droplet discharge head which can effectively eliminate a bubble intermingled in an ink in two or more pressure generating chambers in a liquid-droplet discharge head and a common liquid chamber leading to the former chambers. <P>SOLUTION: The method for introducing the liquid to the liquid-droplet discharge head 10 has the bubble eliminating process of forming a stream of liquid from the common liquid chamber 13 to a suction space 21 by making the pressure of the suction space 21 formed by contact with a sealing member 19 closely to a nozzle face 16a of the liquid-droplet discharge head 10 with an upward posture lower than the pressure of the common liquid chamber 13, the reversion process for reversing the liquid-droplet discharge head 10 to a downward posture with making the pressure of the suction space 21 equal to the pressure of the common liquid chamber 13 and keeping the sealing member 19 in contact with the nozzle face 16a, and the estrangement process for estranging the sealing member 19 from the nozzle face 16a. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for introducing a liquid into a droplet discharge head that discharges ink droplets from a plurality of nozzle openings arranged in parallel, a liquid introduction device that can execute the method, and a droplet discharge recording apparatus that can execute the method. .

  Conventionally, a plurality of pressure generating chambers provided in parallel to individually correspond to a plurality of parallel nozzle openings for discharging ink droplets, a common liquid chamber communicating with each of the plurality of pressure generating chambers, and each pressure There is known a liquid droplet ejection head including an ejection energy generator provided corresponding to each pressure generation chamber in order to eject ink droplets from the generation chamber. In this droplet discharge head, the ink introduced from the common liquid chamber to each pressure generating chamber is discharged as an ink droplet from each nozzle opening by receiving pressure due to the action of the corresponding discharge energy generator. Therefore, in this droplet discharge head, if bubbles are present in the ink introduced into the common liquid chamber and the pressure generation chambers, the ink droplets are discharged from the nozzle openings due to the difference in compression rate between the bubbles and the ink. May not be properly discharged.

  Therefore, an ink jet printer having a droplet discharge head mounted thereon, an ink tank and an ink flow path for supplying ink from the ink tank to the droplet discharge head on a carriage mounted with the droplet discharge head In addition, it is considered to provide a bubble storage chamber for storing bubbles generated in the ink flow path (see, for example, Patent Document 1). In this case, when ink is introduced into the droplet discharge head, it is possible to reduce the mixing of bubbles into the common liquid chamber and each pressure generating chamber. However, in this case, since the bubbles mixed in the ink introduced into the droplet discharge head are reduced, even if bubbles are generated in the droplet discharge head after the ink is introduced, the bubbles are removed. I can't.

  In addition, the ink jet recording apparatus is equipped with a droplet discharge head, and a sub-tank for supplying ink supplied from the main tank to the droplet discharge head is provided on a carriage mounted with the droplet discharge head. It is considered to discharge bubbles mixed from ink in the sub tank (for example, see Patent Document 2). This also reduces bubbles that are mixed into the ink that is introduced into the droplet discharge head, so that even if bubbles are generated in the recording head after the ink is introduced, the bubbles cannot be removed.

  In addition to this, it is known that the ink flow path of the droplet discharge head is previously filled with a filling liquid in order to improve the ink filling property to the droplet discharging head. It is considered to devise (for example, see Patent Document 3). This is effective for removing bubbles during so-called initial ink filling, in which ink is introduced into a droplet discharge head that is filled with a filling liquid, but when using a droplet discharge head. In such a situation, the ink bubbles in the droplet discharge head cannot be removed.

  Therefore, when performing the recovery operation of the droplet discharge head, the droplet discharge head is arranged so that the discharge port (nozzle opening) surface faces upward with respect to the ink liquid chamber (common liquid chamber and each pressure generation chamber) and is elastic. It has been considered that a member is brought into contact with the surface of the discharge port and the discharge port is sucked by the elastic member (for example, see Patent Document 4). Further, as a similar one, the ink jet print cartridge (droplet discharge head) is placed in a state where the nozzle (nozzle opening) side is above the ink chamber (common liquid chamber and each pressure generating chamber), and the nozzle is provided. It has been considered to suck the ink from the nozzle while sealing the surface and pumping the ink into the ink chamber (see, for example, Patent Document 5).

In these Patent Documents 4 and 5, even if air bubbles exist in the ink chamber and the ink in each nozzle, the air bubbles rise in the ink due to the buoyancy acting on the air bubbles, and each nozzle Therefore, when the ink is sucked from the nozzle, the bubbles can be efficiently removed.
JP-A-2005-246828 JP 2001-277535 A JP 2004-66599 A JP-A-10-217510 JP 2000-108383 A

  However, in the above-mentioned Patent Document 4, one or several of the plurality of discharge ports are partially sucked through the elastic member, so that bubbles present in the ink of each discharge port are not affected. Although it may be effective, it is difficult to remove bubbles present in the ink in the ink chamber. Further, when the ink is pumped into the ink chamber, the ink leaks from each ejection port that is not sucked by the elastic member, and the ink jet recording head and its surroundings may be soiled.

  On the other hand, in the above-mentioned Patent Document 5, since the surface on which the nozzle is provided is sealed and ink is sucked from the nozzle, even if ink leaks from each nozzle during suction. As a result, the surroundings can be prevented from being stained, but there is a possibility that the surroundings may be stained by the ink accumulated on the surface where the nozzles are provided after the suction is completed. In addition, when such a method and apparatus are incorporated into a printer (recording apparatus), it is necessary to invert the inkjet print cartridge so that the surface on which the nozzle is provided faces downward. There is a possibility that bubbles are generated in the vicinity of the tip and mixed into the ink in the nozzle or the ink chamber.

  The present invention has been made in view of the above problems, and can effectively remove bubbles mixed in a plurality of pressure generation chambers in a droplet discharge head and liquid in a common liquid chamber communicating with each of the pressure generation chambers. It is an object of the present invention to provide a method for introducing a liquid into a droplet discharge head, a liquid introduction apparatus capable of executing the method, and a droplet discharge recording apparatus capable of executing the method.

  In order to solve the above-mentioned problem, the invention according to claim 1 includes a plurality of nozzle openings for discharging droplets, a plurality of pressure generating chambers provided corresponding to the respective nozzle openings, and the plurality of pressure generating chambers. A common liquid chamber capable of introducing and storing a liquid through each of the pressure generation chambers, and a discharge energy generator provided corresponding to each pressure generation chamber to discharge droplets from each pressure generation chamber; A method for introducing a liquid into a droplet discharge head comprising: disposing the droplet discharge head so that each nozzle opening is positioned vertically above each pressure generating chamber and the common liquid chamber, A sealing member capable of comprehensively covering each nozzle opening is brought into airtight contact with the nozzle surface provided with each nozzle opening to form a suction space between the nozzle surface and the sealing member, The pressure in the suction space is the pressure in the common liquid chamber. A bubble removing step for forming a liquid flow from the common liquid chamber to the suction space at a lower level, and the sealing member in the state where the suction space and the common liquid chamber are filled with the liquid. The inversion step of inverting the droplet discharge head so that the nozzle openings face downward in the vertical direction while being in contact with the nozzle, and the posture in which the nozzle openings of the droplet discharge head face downward in the vertical direction are maintained. And a separation step of separating the sealing member from the nozzle surface.

  The invention according to claim 2 is the liquid introduction method to the droplet discharge head according to claim 1, wherein in the reversing step, the pressure of the suction space and the pressure of the common liquid chamber are equalized, While the sealing member is in contact with the nozzle surface, the droplet discharge head is inverted so that the nozzle openings face downward in the vertical direction.

  The invention according to claim 3 is the liquid introduction method to the droplet discharge head according to claim 1 or 2, wherein in the bubble removal step, the liquid is pumped into the common liquid chamber, thereby The pressure in the suction space is made lower than the pressure in the common liquid chamber.

  According to a fourth aspect of the present invention, there is provided the method for introducing a liquid into the droplet discharge head according to the first or second aspect, wherein, in the bubble removing step, the suction space is decompressed to reduce the suction space. The pressure is made lower than the pressure of the common liquid chamber.

  The invention according to claim 5 is the liquid introduction method to the droplet discharge head according to claim 1 or 2, wherein, in the bubble removing step, the suction space while pumping the liquid into the common liquid chamber. The pressure in the suction space is made lower than the pressure in the common liquid chamber by reducing the pressure.

  The invention according to claim 6 is the liquid introduction method to the droplet discharge head according to any one of claims 1 to 5, wherein each of the droplet discharge heads after the separation step. A wiping step of wiping the nozzle surface with a wiping member is performed in a state in which the nozzle opening is maintained in a vertically downward position.

  In order to solve the above-mentioned problem, an invention according to claim 7 includes a plurality of nozzle openings for discharging droplets, a plurality of pressure generating chambers provided corresponding to the nozzle openings, and the plurality of pressure generating chambers. A common liquid chamber capable of introducing and storing a liquid through each of the pressure generation chambers, and a discharge energy generator provided corresponding to each pressure generation chamber to discharge droplets from each pressure generation chamber; An apparatus for introducing a liquid into a droplet discharge head comprising: a head holding unit capable of holding the droplet discharge head; and the droplet discharge head held by the head holding unit, each nozzle opening having the nozzle opening A head displacing means for displacing between each of the pressure generation chambers and the upward posture positioned vertically above the common liquid chamber and a downward posture where each nozzle opening faces downward in the vertical direction; and Retained A liquid introducing means capable of pumping liquid to the common liquid chamber of the droplet discharge head; and the nozzle openings of the droplet discharge head can be covered comprehensively; A sealing member capable of airtight contact with the nozzle surface provided with each nozzle opening and capable of forming a suction space in cooperation with the nozzle surface by airtight contact; A sealing member holding means for holding the sealing member in a displaceable manner with respect to the droplet discharge head held by the head holding means to form the suction space; Sealing member displacing means that can cause the sealing member in a state in which the suction space is formed to follow displacement of the droplet discharge head by the head displacing means, and suction means that can depressurize the suction space. And up The pressure of the suction space formed by bringing the sealing member into contact with the nozzle surface of the droplet discharge head in a posture is made lower than the pressure of the common liquid chamber, and the pressure from the common liquid chamber to the suction space. The liquid droplet ejection head is reversed while the sealing member is in contact with the nozzle surface in a state where the suction space and the common liquid chamber are filled with liquid. And performing a reversing step for turning the droplet discharge head downward, and a separation step for separating the sealing member from the nozzle surface while maintaining the downward posture of the droplet discharge head. And

  The invention according to claim 8 is the liquid introducing device to the droplet discharge head according to claim 7, wherein, in the reversing step, the pressure in the suction space and the pressure in the common liquid chamber are equalized, The liquid droplet ejection head is inverted while the sealing member is in contact with the nozzle surface, so that the liquid droplet ejection head is in a downward posture.

  The invention according to claim 9 is the apparatus for introducing a liquid into the droplet discharge head according to claim 7 or claim 8, wherein in the bubble removing step, the liquid introduction means pumps the liquid into the common liquid chamber. By doing so, the pressure of the suction space is made lower than the pressure of the common liquid chamber.

  The invention according to claim 10 is the liquid introducing device to the droplet discharge head according to claim 7 or claim 8, wherein, in the bubble removing step, the suction means depressurizes the suction space. The pressure in the suction space is made lower than the pressure in the common liquid chamber.

  According to an eleventh aspect of the present invention, there is provided the liquid introducing device to the droplet discharge head according to the seventh or eighth aspect, wherein in the bubble removing step, the liquid introducing means pumps the liquid into the common liquid chamber. However, the suction means depressurizes the suction space, whereby the pressure of the suction space is made lower than the pressure of the common liquid chamber.

  The invention according to a twelfth aspect is the liquid introducing device to the droplet discharge head according to any one of the seventh to eleventh aspects, wherein the nozzle is further slid by sliding on the nozzle surface. Wiping member holding means for holding a wiping member capable of wiping the surface, and wiping for moving the wiping member held by the wiping member holding means so as to wipe the nozzle surface of the droplet discharge head in a downward posture And a member moving means, and after the separating step, performing a wiping step of wiping the nozzle surface with the wiping member in a state where the droplet discharge head is maintained in a downward posture.

  In order to solve the above-mentioned problems, an invention according to claim 13 is a liquid comprising the liquid introduction device to the droplet discharge head according to any one of claims 7 to 12 and the droplet discharge head. In the droplet discharge recording apparatus, the head holding unit is a carriage for moving the droplet discharge head in the main scanning direction when a droplet is discharged from the nozzle opening of the droplet discharge head for printing. And the head displacing means rotates the carriage around a guide rod for moving the carriage.

  In order to solve the above-mentioned problem, an invention according to claim 14 is a stationary apparatus comprising the liquid introduction device for a droplet discharge head according to any one of claims 7 to 12 and the droplet discharge head. Type droplet discharge recording apparatus, wherein the head displacing means is a rotating shaft of a transport roller for circularly moving a transport belt for transporting a recording medium recorded by droplets discharged from the droplet discharge head The droplet discharge head is rotated around.

  A fifteenth aspect of the invention is the droplet discharge recording apparatus according to the thirteenth or fourteenth aspect, wherein the liquid introduction device performs the bubble removal step, the inversion step, and the separation step. Separately from the maintaining operation, the pressure of the suction space formed by bringing the sealing member into contact with the nozzle surface of the droplet discharge head in the downward posture is made lower than the pressure of the common liquid chamber, A second maintenance operation for performing a flow path cleaning process for forming a flow of liquid from the liquid chamber to the suction space can be performed.

  The invention according to claim 16 is the droplet discharge recording apparatus according to claim 15, wherein the second maintenance operation is a normal maintenance operation that is appropriately executed to maintain the function of the droplet discharge head. It is characterized by being set.

  The invention according to claim 17 is the droplet discharge recording apparatus according to claim 15, wherein the first maintaining operation is performed on the droplet discharge head that is not filled with a printing liquid for printing. It is performed to fill the printing liquid.

  The invention according to claim 18 is the droplet discharge recording apparatus according to claim 15, wherein the first maintenance operation is executed to recover the function of the deteriorated droplet discharge head. And

  In the liquid introduction method to the droplet discharge head according to the present invention, in the bubble removal step, the droplet discharge head is disposed so that the nozzle opening is positioned above each pressure generation chamber and the common liquid chamber. Even if bubbles exist in the liquid in the common liquid chamber and each pressure generating chamber, the bubbles can be collected in the vicinity of each pressure generating chamber or in the vicinity of each nozzle opening. In this state, a flow of liquid from the common liquid chamber to the suction space through each pressure generation chamber and each nozzle opening is formed, so that bubbles existing in the liquid in the common liquid chamber and each pressure generation chamber are removed. The liquid discharged into the suction space can be efficiently discharged into the suction space.

  Further, in the reversing step, the droplet discharge head is reversed while the common liquid chamber and the suction space are filled with the liquid, so that bubbles can be prevented from being generated at the nozzle opening during the reversal.

  Furthermore, since the reversing step and the separation step are performed after the bubble removing step, the liquid discharged into the suction space in the bubble removing step can be discharged through the sealing member, so that the nozzle surface and surroundings are soiled. Can be prevented.

  In addition to the configuration described above, in the reversing step, the pressure in the suction space and the pressure in the common liquid chamber are equalized, and the nozzle openings are kept vertical while the sealing member is kept in contact with the nozzle surface. If the liquid droplet ejection head is reversed so as to face downward in the direction, it is possible to more stably prevent bubbles from being generated at the nozzle opening during the reversal.

  In addition to the above-described configuration, after the separation step, a wiping step of wiping the nozzle surface with a wiping member is performed in a state in which each nozzle opening of the droplet discharge head is kept facing downward in the vertical direction. As a result, since the wiping step is further performed after the separation step, even if the liquid discharged into the suction space in the bubble removal step adheres to the nozzle surface, the adhering liquid remains on the nozzle surface and its surroundings. Can be prevented.

  In the apparatus for introducing liquid into the droplet discharge head according to the present invention, it is possible to introduce liquid into the droplet discharge head by executing the above-described liquid introduction method regardless of whether or not the liquid is initially filled. Therefore, it is possible to reliably prevent bubbles from entering the introduced liquid.

  In the droplet discharge recording apparatus for the droplet discharge head according to the present invention, the liquid is introduced into the droplet discharge head by executing the above-described liquid introduction method regardless of whether or not the liquid is initially filled. Therefore, it is possible to reliably prevent bubbles from being mixed into the introduced liquid.

  In addition to the above-described configuration, in the liquid introducing device, apart from the first maintenance operation for performing the bubble removal step, the inversion step, and the separation step, A flow path cleaning step is performed in which the pressure of the suction space formed by contacting the sealing member is lower than the pressure of the common liquid chamber to form a liquid flow from the common liquid chamber to the suction space. Assuming that the second maintenance operation can be executed, the second maintenance operation that can be easily executed and the first maintenance operation aiming at the recovery of the function of the droplet discharge head more appropriately can be appropriately used.

  In addition to the above-described configuration, if the second maintenance operation is set as a normal maintenance operation that is appropriately executed to maintain the function of the droplet discharge head, the second maintenance operation is performed as a normal maintenance operation. Is appropriately executed, the droplet discharge head can be maintained in a good state.

  In addition to the above-described configuration, it is assumed that the first maintenance operation is performed to fill the liquid droplet ejection head not filled with the printing liquid for printing with the printing liquid. When the initial printing liquid is filled, bubbles can easily be mixed into the liquid, so that the initial printing liquid can be more appropriately filled.

  In addition to the above-described configuration, if the first maintenance operation is performed to restore the function of the deteriorated liquid droplet ejection head, when the printing state deteriorates, the common liquid chamber and Since it is considered that bubbles are mixed in the liquid in each pressure generating chamber, the function of the droplet discharge head can be recovered more appropriately by performing the first maintenance operation.

  Hereinafter, embodiments of a liquid introduction method to a liquid droplet ejection head according to the present invention, a liquid introduction apparatus capable of executing the method, and a liquid droplet ejection recording apparatus capable of performing the method will be described with reference to the drawings. .

  FIG. 1 is a perspective view schematically showing a droplet discharge head 10 in which a method for introducing a liquid into the droplet discharge head according to the present invention is performed. FIG. 2 shows the droplet discharge head 10 from the nozzle opening 11 side. It is the bottom view seen. 3 is a schematic cross-sectional view obtained along the line II shown in FIG. 2, and FIG. 4 is a schematic cross-section obtained along the line II-II shown in FIG. FIG.

  In this embodiment, as shown in FIGS. 1 and 2, the droplet discharge head 10 is directed from a plurality of nozzle openings 11 scattered along two lines parallel to each other to a recording target (not shown). Ink droplets are ejected. In this droplet discharge head 10, a pressure generation chamber 12 is provided corresponding to each nozzle opening 11, and a common liquid chamber 13 communicating with each of the pressure generation chambers 12 is provided. In the present embodiment, two common liquid chambers 13 are provided corresponding to each row of the plurality of nozzle openings 11 that are scattered in two rows. The plurality of pressure generating chambers 12 are formed on a substrate 14, and a top plate 15 and a nozzle plate 16 are attached to the substrate 14 to configure the droplet discharge head 10. The two common liquid chambers 13 are formed by a recess provided in the substrate 14 and a recess provided in the top plate 15. A plurality of nozzle openings 11 are formed in the nozzle plate 16.

  In this droplet discharge head 10, as shown in FIG. 3, a discharge energy generator 17 (an electrode for applying a discharge signal to the generator and an electrode provided on the generator as needed) corresponding to each pressure generating chamber 12. The protective layer and the like are omitted). When a recording signal is applied to the ejection energy generator 17 via an electrode (not shown), the ejection energy corresponding to the signal is applied to the ink in the corresponding pressure generation chamber 12 and the nozzle opening leading to the ink is generated. 11 is ejected as ink droplets. The discharge energy generator 17 may be, for example, an electrostrictive element (so-called piezo method) that is deformed by application of voltage as long as it discharges ink in the pressure generation chamber 12 as described above. It may be an electrothermal conversion element (so-called thermal method) that generates heat when an electric current is applied. In the piezo method, ink droplets of various sizes can be ejected by adjusting their drive waveforms by enlarging or reducing the size of the piezo elements or adjusting the deformation amount of the piezo elements. Therefore, the piezo method is advantageous for forming an image with good gradation. On the other hand, the thermal method is suitable for manufacturing a multi-nozzle head because it is easy to highly integrate nozzles. Therefore, the thermal method is advantageous for printing an image with high resolution at high speed.

  In the droplet discharge head 10, the ink I is introduced from the ink tank 18 (see FIG. 5) to the common liquid chamber 13. The ink I introduced into the common liquid chamber 13 is temporarily held in the common liquid chamber 13 and enters each pressure generating chamber 12 communicating therewith, and forms a meniscus at the corresponding nozzle opening 11. . As a result, each pressure generating chamber 12 is maintained in a state filled with ink I. The ink I in each pressure generating chamber 12 is ejected from the nozzle opening 11 as an ink droplet by the ejection energy generator 17.

  Bubbles may be mixed in the ink I in the common liquid chamber 13 and each pressure generating chamber 12. These bubbles are likely to be mixed into the ink I due to wettability problems when the ink I is introduced into the droplet discharge head 10 to which the ink I has not yet been introduced, that is, the common liquid chamber 13 and the pressure generation chambers 12. In addition, bubbles are mixed into the ink I when the droplet discharge head 10 into which the ink I has already been introduced, that is, the common liquid chamber 13 and the pressure generation chambers 12 are operating to discharge ink droplets. Resulting in. Such a bubble has a higher compression ratio than that of the ink I, and therefore is not preferable for the printing operation, that is, for the ejection of ink droplets by the ejection energy generator 17, in view of the pressure characteristics, and the appropriate printing is hindered. There is a risk of being.

  This bubble can be removed from the ink I in the droplet discharge head 10, that is, the common liquid chamber 13 and each pressure generation chamber 12 by performing the liquid introduction method to the droplet discharge head according to the present invention. In the following, for easy understanding, the liquid introduction method to the liquid droplet ejection head according to the present invention will be described using one common liquid chamber 13, each pressure generating chamber 12 communicating therewith, and each nozzle opening 11.

  First, as shown in FIG. 5, an ink tank 18 for introducing ink I is connected to an inlet 13 a that communicates with a common liquid chamber 13 provided in the droplet discharge head 10. The ink tank 18 is capable of pumping the ink I to be stored. The ink tank 18 is capable of pumping the ink I in which bubbles are not mixed. The droplet discharge head 10 in which the ink tank 18 is connected to the common liquid chamber 13 is arranged so that the nozzle opening 11 is positioned vertically above the common liquid chamber 13 and each pressure generating chamber 12 (FIG. 7 ( a)). Hereinafter, the state of the droplet discharge head 10 is referred to as an upward posture. A cap 19 as a sealing member is brought into airtight contact with the nozzle surface 16a defined by the nozzle plate 16 provided with the nozzle openings 11 in the droplet discharge head 10.

  The cap 19 is formed of an elastic member. As shown in FIG. 6, one end 19a has a large diameter, the other end 19b has a small diameter, and the diameter is continuously increased from the one end 19a to the other end 19b. It has a funnel shape with a conical portion 19c that decreases. One end 19a of the cap 19 is sized so that all the nozzle openings 11 can be positioned within the diameter, and can be tightly adhered to the nozzle surface 16a. The other end 19 b of the cap 19 communicates with the suction device 20. The suction device 20 can suck from the other end 19 b side of the cap 19.

  When the one end 19a is hermetically adhered to the nozzle surface 16a so that all the nozzle openings 11 are located in the opening of the one end 19a, the cap 19 cooperates with the nozzle surface 16a and the suction space 21 (FIG. 5 and FIG. 7 (a)). The suction space 21 communicates all the nozzle openings 11 of the droplet discharge head 10 with the suction device 20, and all the nozzle openings when the droplet discharge head 10 is in the upward posture. 11 is located above the vertical direction.

  In the droplet discharge head 10 (see FIG. 7A) in this upward posture and the cap 19 being in close contact, the ink I is pumped from the ink tank 18 to the common liquid chamber 13 as shown in FIG. 7B. At the same time, the suction space 21 is decompressed by the suction device 20. As a result, a flow of ink I from the common liquid chamber 13 to the suction space 21 through each pressure generating chamber 12 and each nozzle opening 11 communicating therewith is formed. This is the bubble removal step.

  In this bubble removing step, the ink I oozes out from each nozzle opening 11, and the ink I accumulates on the nozzle surface 16 a, that is, in the suction space 21. As shown in FIG. 7C, this bubble removing step is performed until at least the liquid surface of the ink I on the nozzle surface 16a reaches the other end 19b, in other words, until the inside of the suction space 21 is filled with the ink I. . At this time, since the droplet discharge head 10 is in the upward posture, the buoyancy acts on the bubbles, so that the bubbles mixed in the ink I in the common liquid chamber 13 move to the vicinity of each pressure generating chamber 12. However, the bubbles mixed in the ink I in each pressure generating chamber 12 have moved to the vicinity of each nozzle opening 11. In other words, bubbles mixed in the ink I in the common liquid chamber 13 and each pressure generation chamber 12 can be collected in the vicinity of each pressure generation chamber 12 or each nozzle opening 11. In addition, the direction of movement of the bubbles coincides with the direction of the flow formed in the ink I. For this reason, when the flow of ink I from the common liquid chamber 13 to the suction device 20 through the pressure generation chambers 12, the nozzle openings 11 and the suction spaces 21 is formed, the common liquid chamber 13 and the pressure generation chambers 12 Air bubbles mixed in the ink I are efficiently and reliably guided to the suction device 20 together with the ink I.

  Thus, in the bubble removal step, the flow of the ink I from the common liquid chamber 13 to the suction space 21 formed by the cap 19 covering all the nozzle openings 11 is formed. In addition, not only bubbles existing in the vicinity of each pressure generating chamber 12 but also bubbles existing in the common liquid chamber 13 can be reliably removed. This is because bubbles existing in the vicinity of each pressure generation chamber 12 can be efficiently sucked out into the suction space 21 by decompression of the suction space 21 by the suction device 20, and bubbles present in the common liquid chamber 13 are removed from the ink tank 18. It is conceivable that the ink I can be prevented from staying in the common liquid chamber 13 by being pumped to the common liquid chamber 13 and moved to the vicinity of each pressure generating chamber 12.

  After this bubble removal step, while the cap 19 is kept in close contact with the nozzle surface 16a, the pumping of the ink I from the ink tank 18 to the common liquid chamber 13 is stopped and the suction device 21 is decompressed. And the pressure of the common liquid chamber 13 filled with the ink I is made equal to the pressure of the suction space 21. With the cap 19 kept in close contact with the nozzle surface 16a and with the common liquid chamber 13 and the suction space 21 at the same pressure, as shown in FIG. The liquid droplet ejection head 10 is inverted so as to be positioned at the position. Hereinafter, the state of the droplet discharge head 10 is referred to as a downward posture. The operation of reversing the droplet discharge head 10 is a reversal process.

  In this reversal process, the common liquid chamber 13 and the suction space 21 are both filled with the ink I and have the same pressure, so that bubbles are mixed into the ink I of the droplet discharge head 10. This can be prevented.

  Thus, after the droplet discharge head 10 is set in the downward posture, as shown in FIG. 7E, the cap 19 is moved downward from the nozzle surface 16a to be separated from the nozzle surface 16a, and the common liquid chamber 13 is moved. Is set to a slightly lower pressure than the atmosphere around the droplet discharge head 10. At this time, the cap 19 is moved downward while the one end 19a is maintained in a horizontal state. The operation of separating the cap 19 from the droplet discharge head 10 is a separation process. In the present embodiment, in addition to this, when the cap 19 is separated from the nozzle surface 16a, suction by the suction device 20 is started at the same time or immediately before being separated.

  In this separation step, the ink I filling the suction space 21 is stored in the cone portion 19c of the cap 19 and is prevented from spilling around. Further, in this embodiment, since the suction by the suction device 20 is started as the cap 19 is separated from the nozzle surface 16a, the ink I filling the suction space 21 stored in the cone portion 19c of the cap 19 is discharged. It can prevent more reliably that it spills around.

  After the separation step, as shown in FIG. 7F, the nozzle surface 16a of the droplet discharge head 10 is wiped with a wiper 22 as a wiping member. The wiper 22 only needs to be capable of wiping off the ink I attached to the nozzle surface 16a. This is the wiping process.

  Even if the ink I adheres to the nozzle surface 16a of the droplet discharge head 10 by this wiping process, the ink I can be completely removed. In the wiping process, since the common liquid chamber 13 is slightly lower in pressure than the atmosphere around the droplet discharge head 10, the meniscus is generated at each nozzle opening 11 by the ink I filled therein. It is formed.

  In the liquid introduction method according to the present invention, in the bubble removal step, the flow of the ink I from the common liquid chamber 13 to the suction space 21 is formed with the droplet discharge head 10 in the upward posture. Air bubbles mixed in the ink I in the generation chamber 12 can be efficiently and reliably removed from the common liquid chamber 13 or each pressure generation chamber 12. This is because, when the droplet discharge head 10 is in the upward posture, bubbles mixed in the ink I in the common liquid chamber 13 can be collected in the vicinity of each pressure generating chamber 12 and the ink I in each pressure generating chamber 12 can be collected. Bubbles can be collected in the vicinity of each nozzle opening 11, so that the bubbles can be preferentially discharged when the ink I is discharged to the suction space 21 (suction device 20). This is because the bubbles can be reliably discharged, that is, removed from the common liquid chamber 13 or each pressure generating chamber 12 while suppressing the discharge amount of I.

  Further, in the liquid introducing method according to the present invention, the liquid droplet ejection head 10 is reversed in the state in which the suction space 21 and the common liquid chamber 13 are filled with the ink I during the reversing step. It is possible to prevent bubbles from being generated at each nozzle opening 11 during the reversal of 10 and mixing the bubbles into the ink I in each pressure generating chamber 12 and the common liquid chamber 13 from the nozzle opening 11. This is because, in each nozzle opening 11 filled with ink I inside, if the outside is air, the external air is applied to the ink I in each nozzle opening 11 due to the impact when the droplet discharge head 10 is reversed. It is because there is a possibility that bubbles may be formed by mixing. Further, when the liquid droplet ejection head 10 is reversed, a load is applied to the pipe communicating the common liquid chamber 13 and the ink tank 18, and the pressure on the common liquid chamber 13 fluctuates due to the load on the pipe. This is because external air is taken in from each nozzle opening 11, which may cause bubbles to be mixed into the ink I in each nozzle opening 11.

  Furthermore, in the liquid introduction method according to the present invention, the droplet discharge head 10 is inverted with the suction space 21 and the common liquid chamber 13 set to the same pressure during the reversing step. Since the flow of the ink I is stopped and the state of the ink I is stabilized and then reversed, it is possible to prevent bubbles from being mixed into the ink I in the pressure generation chambers 12 and the common liquid chamber 13 from the nozzle openings 11. be able to. This is because, in a state where the flow of the ink I from the common liquid chamber 13 to the suction space 21 is formed, there is a possibility that fine bubbles may stay in the vicinity of the nozzle opening 11 in the suction space 21. Then, there is a possibility that the fine bubbles may enter the nozzle opening 11. However, when the flow of the ink I is stopped and the state of the ink I is stabilized, the fine bubbles are separated from the vicinity of the nozzle opening 11, that is, the suction space. This is because it can be moved above 21. Further, if the flow of the ink I is stopped to stabilize the state of the ink I and the reversal process is performed, the process can immediately shift to the separation process, and the liquid can be introduced (bubble removal) quickly.

  In the liquid introduction method according to the present invention, the separation process is performed after the bubble removal process and then the separation process, so that the ink I filled in the suction space 21 contaminates the droplet discharge head 10 and its surroundings. This can be prevented.

  In the liquid introduction method according to the present invention, in the bubble removing step, the ink I is pumped from the ink tank 18 to the common liquid chamber 13 and the suction space 21 is decompressed by the suction device 20. Ink I can be efficiently flowed into the space 21, and the occurrence of stagnation in the flow of the ink I in the common liquid chamber 13 and each pressure generating chamber 12 can be suppressed. Accordingly, bubbles mixed in the ink I in the common liquid chamber 13 or each pressure generation chamber 12 can be efficiently and reliably removed from the common liquid chamber 13 or each pressure generation chamber 12. In addition, the ink flow paths from the common liquid chamber 13 and the pressure generation chambers 12 to the nozzle openings 11 can be efficiently maintained (maintenance) and recovered, that is, maintained.

  In the liquid introducing method according to the present invention, the suction by the suction device 20 is started simultaneously with the separation of the cap 19 from the nozzle surface 16a in the separation step, so that the suction space 21 stored in the cone portion 19c of the cap 19 is used. It is possible to more reliably prevent the ink I satisfying the above from spilling around.

  In the liquid introduction method according to the present invention, since the cleaning process is performed after the separation process, even if the ink I adheres to the nozzle surface 16a after the bubble removal process and the reversing process, the ink I Therefore, it is possible to reliably prevent the droplet discharge head 10 and its surroundings from being soiled.

  Therefore, in the liquid introduction method according to the present invention, it is possible to effectively remove bubbles mixed in the plurality of pressure generating chambers 12 in the droplet discharge head 10 and the ink I in the common liquid chamber 13 communicating with each of the pressure generating chambers 12. .

  In the liquid introducing method according to the present invention, in the above-described embodiments, the bubbles mixed in the ink I in the common liquid chamber 13 and the pressure generating chambers 12 of the droplet discharge head 10 into which the ink I has already been introduced. However, when the ink is introduced into the liquid droplet ejection head to which the ink has not yet been introduced (the liquid filling may or may not be introduced), the liquid filling the empty liquid droplet ejection head. It may be performed when introducing. This filling liquid refers to the common liquid chamber and the common liquid chamber prior to the introduction of the ink I in order to improve the ink filling property in consideration of the wettability of the common liquid chamber and each pressure forming chamber of the droplet discharge head 10. It is introduced into each pressure forming chamber or the like.

  Next, a liquid introduction device 30 capable of performing the above-described liquid introduction method will be described with reference to FIGS. 8 and 9. FIG. 8 is an explanatory diagram schematically illustrating the configuration of the liquid introduction device 30, and FIG. 9 is an explanatory diagram schematically illustrating the configuration of the liquid introduction device 30 as viewed from the arrow A1 side illustrated in FIG. Hereinafter, a scene in which ink is introduced into the droplet discharge head 10 into which the filling liquid has been introduced using the liquid introduction device 30 will be described.

  As shown in FIGS. 8 and 9, the liquid introduction device 30 includes a reverse shaft 31, a head holding mechanism 32, and a cap holding mechanism 33. Although not shown, the reversing shaft 31 is held by a case that forms the outer shape of the liquid introduction device 30 and extends in the horizontal direction. A head holding mechanism 32 and a cap holding mechanism 33 are supported on the reversing shaft 31 so as to be rotatable around the reversing shaft 31.

  The head holding mechanism 32 includes a head reversing unit 34 and a head holding unit 35. The head holding unit 35 can hold the droplet discharge head 10 in a detachable manner, and functions as a head holding unit that can hold the droplet discharge head. In this embodiment, the head holding mechanism 32 can hold the four droplet discharge heads 10.

  The head reversing unit 34 is configured to be reversible around the reversing shaft 31 so that each droplet discharge head 10 held by the head holding unit 35 can have both a downward posture and an upward posture. The reversal of the head reversing unit 34 around the reversing axis 31 is performed under the control of a control unit (not shown). Therefore, the control unit, the head reversing unit 34, and the reversing shaft 31 function as a head displacing unit that displaces the droplet discharge head held by the head holding unit between a downward posture and an upward posture.

  A tube 36 connected to the ink tank 18 is guided to the head holding mechanism 32. In the head holding mechanism 32, when the head holding unit 35 appropriately holds the droplet discharge head 10, the common liquid chamber 13 of the held droplet discharge head 10 and one end 36 a of the tube 36 from the ink tank 18 are connected to the outside. It is configured to communicate in a sealed state. For this reason, ink can be pumped from the ink tank 18 in the common liquid chamber 13 of the droplet discharge head 10 attached to the head holding mechanism 32. In this embodiment, since two common liquid chambers 13 are provided in each droplet discharge head 10, two tubes 36 are guided to one head holding portion 35. The ink is pumped from the ink tank 18 to the common liquid chamber 13 under the control of a control unit (not shown). For this reason, the control unit and the ink tank 18 function as a liquid introduction unit capable of pumping liquid to the common liquid chamber of the droplet discharge head.

  The cap holding mechanism 33 includes a cap holding part 37, a cap parallel moving part 38, and a cap reversing part 39. The cap holding part 37 holds the cap 19 whose other end 19b is connected to the suction device 20 via a compression spring 37a. The cap holding portion 37 is configured to correspond to each head holding portion 35 of the head holding mechanism 32, and holds four caps 19 in this embodiment. Each cap holding portion 37 is supported on the reversing shaft 31 via a cap parallel moving portion 38 and a cap reversing portion 39.

  The cap reversing unit 39 is reversible around the reversing shaft 31, and causes the cap parallel moving unit 38 and each cap holding unit 37 provided there to follow the reversal of the head reversing unit 34 of the head holding mechanism 32. . The cap reversing part 39 is provided with a cap parallel moving part 38.

  The cap translation unit 38 causes each cap 19 to closely contact the nozzle surface 16a of each droplet discharge head 10 held by the head holding unit 35 of the head holding mechanism 32, or separates each cap 19 from the nozzle surface 16a. Each cap holding part 37 can be moved in parallel. The cap translation unit 38 causes the caps 19 to be in close contact with the nozzle surfaces 16a of the liquid droplet ejection heads 10 held by the head holding unit 35 of the head holding mechanism 32, whereby the suction space 21 (FIGS. 5 and 7). Reference) can be formed. For this reason, the cap parallel moving part 38 and each cap holding part 37 function as a sealing member holding means for holding the cap (sealing member) displaceably with respect to the droplet discharge head held by the head holding means. .

  In the cap holding mechanism 33, each droplet discharge head 10 held by the head holding unit 35 of the head holding mechanism 32 is in a downward posture or an upward posture in cooperation with the cap parallel moving unit 38 and the cap reversing unit 39. Regardless of the state, it is possible to maintain the state in which the caps 19 are in close contact with the nozzle surfaces 16a, that is, the state in which the suction space 21 is formed. The cap 19 of the cap holding mechanism 33 (cap parallel moving unit 38 and cap reversing unit 39) is moved up and down and reversed around the reversing shaft 31 under the control of a control unit (not shown). For this reason, the cap reversing unit 39 cooperates with the control unit and the reversing shaft 31 to allow the cap (sealing member) to follow the displacement of the droplet discharge head by the head displacement unit. Function as.

  In addition, the suction device 20 connected to the four caps 19 held by the cap holding mechanism 33 passes through the suction space 21 formed by each cap 19 in cooperation with the nozzle surface 16 a of the corresponding droplet discharge head 10. It is possible to reduce the pressure (suction). For this reason, this suction device 20 functions as a suction means that can depressurize the suction space.

  The liquid introduction device 30 operates as follows under the control of a control unit (not shown).

  First, the four droplet discharge heads 10 are appropriately mounted on the head holding portion 35 of the head holding mechanism 32. As a result, the common liquid chamber 13 of each droplet discharge head 10 (two for each droplet discharge head 10) is appropriately connected to one end 36a of the tube 36 extending from the ink tank 18.

  In a state where each droplet discharge head 10 held by the head holding mechanism 32 is in a downward posture, the cap parallel moving portion 38 of the cap holding mechanism 33 moves the cap 19 held by each cap holding portion 37 to each droplet discharge head. The suction space 21 is formed in close contact with the ten nozzle surfaces 16a.

  The cap 19 in close contact with each droplet discharge head 10 and its nozzle surface 16 a is rotated 180 around the reversing shaft 31 by the cooperation of the head reversing portion 34 of the head holding mechanism 32 and the cap reversing portion 39 of the cap holding mechanism 33. The liquid droplet ejection head 10 is set in the upward posture while the suction space 21 is formed (see the liquid droplet ejection head 10 indicated by a two-dot chain line in FIG. 9).

  Thereafter, the suction device 20 and the ink tank 18 are operated, and the bubble removing step is executed. This bubble removal process is executed until the ink I introduced through the droplet discharge head 10 fills at least the suction space 21 (see FIG. 7C).

  After the bubble removing step, the pressures of the common liquid chamber 13 filled with the ink I and the suction space 21 are made equal by the cooperation of the suction device 20 and the ink tank 18, and the head holding mechanism 32 and the cap holding mechanism 33 In cooperation, each droplet discharge head 10 and the cap 19 in close contact with the nozzle surface 16a are inverted 180 degrees around the inversion shaft 31 to form the suction space 21, and the droplet discharge head 10 is in the downward posture. Then, the inversion process is executed.

  After the reversing step, the cap translation unit 38 of the cap holding mechanism 33 separates each cap 19 from the nozzle surface 16a, whereby the separating step is executed.

  Thereby, execution of the liquid introduction method by the liquid introduction device 30 is completed. Here, it is also possible to provide a wiping member moving mechanism 40 as a wiping member moving means for sliding the wiper 22 conventionally used on the nozzle surface 16a of the droplet discharge head 10 and performing the wiping step after the reversing step. Good. The wiping member moving mechanism 40 is configured such that an arm portion 40a that holds the wiper 22 is held by a main body portion 40b so as to freely advance and retract. For this reason, the arm part 40a functions as a wiping member holding means, and the arm part 40a and the main body part 40b function as a wiping member moving means.

  Since the liquid introducing device 30 fills each droplet discharge head 10 with the ink I of the ink tank 18 by executing the liquid introducing method according to the present invention, the same effect as the liquid introducing method is obtained. As a result, each droplet discharge head 10 can be appropriately filled with ink without mixing bubbles.

  Next, a droplet discharge recording apparatus 60 capable of performing the above-described liquid introduction method will be described with reference to FIGS. FIG. 10 is a schematic perspective view showing the droplet discharge recording apparatus 60. FIG. 11 is a schematic view of the inside of the droplet discharge recording apparatus 60 as viewed in the main scanning direction to be described later in order to explain the internal configuration of the droplet discharge recording apparatus 60. FIG. 12 is a schematic explanatory diagram viewed along the arrow A2 shown in FIG.

  The droplet discharge recording apparatus 60 is configured such that a paper feed tray 62 is attached to an apparatus main body 61 and a paper discharge tray 63 is detachably attached. The paper feed tray 62 is for loading a recording paper S (see FIGS. 11 and 12) as a recording medium into the apparatus main body 61, and the paper discharge tray 63 is a recording paper S on which an image is recorded (formed). It is to be loaded (stocked).

  The apparatus main body 61 has a cartridge loading portion 64 at a position where one end portion side (the side of the paper feed tray 62 and the paper discharge tray 63) of the front surface in FIG. The upper surface (65) of the cartridge loading unit 64 is set lower than the upper surface of the apparatus main body 61, and an operation button, a display, and the like are provided as the operation / display unit 65.

  The cartridge loading portion 64 is a portion where the liquid cartridge 66 is loaded, and can be loaded by being inserted from the opening on the front side of the apparatus main body 61 toward the rear side. The cartridge loading section 64 is provided with a front cover (cartridge cover) 67 for opening and closing an opening on the front side for loading the liquid cartridge 66. In the cartridge loading unit 64, a plurality of liquid cartridges 66 containing liquids (inks) of different colors are inserted and loaded from the front side to the rear side of the apparatus main body 61, respectively. In this embodiment, the liquid cartridge 66 is a liquid cartridge 66y containing yellow (Y) ink, a liquid cartridge 66m containing magenta (M) ink, a liquid cartridge 66c containing cyan (C) ink, and a black (K). A liquid cartridge 66k containing ink (hereinafter referred to as a liquid cartridge 66 when the colors are not distinguished) is used.

  As shown in FIGS. 11 and 12, the droplet discharge recording device 60 (device main body 61) includes a carriage 68 on which the droplet discharge heads 10 described above are mounted, a main guide rod 69 that supports the carriage 68, and the like. And a secondary guide rod 70. The main guide rod 69 and the sub guide rod 70 are parallel to each other, and are provided across the main side plates 71 a and 71 b (see FIG. 12) of the frame 71 that forms the outer shape of the apparatus main body 61. A carriage 68 is supported so as to be slidable along the extending direction of the main guide rod 69 and the sub guide rod 70.

  The carriage 68 moves along the extending direction (see arrow A3 in FIG. 12) on the main guide rod 69 and the sub guide rod 70 by the driving force from the main scanning motor received via the timing belt although not shown. It is possible. This moving direction (see arrow A3 in FIG. 12) is the main scanning direction in the droplet discharge recording apparatus 60.

  In the carriage 68, a plurality of droplet discharge heads 10 containing liquids (inks) of different colors are in a downward posture (each nozzle opening 11 faces a conveyance belt 83 described later). It is mounted in parallel. In this embodiment, as the droplet discharge head 10, a droplet discharge head 10Y for discharging yellow (Y) droplets, a droplet discharge head 10M for discharging magenta (M) droplets, cyan ( C) droplet discharge head 10C for discharging droplets, and droplet discharge head 10K for discharging black (K) droplets (hereinafter referred to as droplet discharge head 10 when the colors are not distinguished). ) Is used.

  In this embodiment, the carriage 68 is provided with four liquid tanks 72 that correspond to the respective liquid discharge heads 10 and communicate with the common liquid chamber 13 (see FIGS. 2 and 3). Each of the liquid tanks 72 is connected to a corresponding liquid cartridge 66 mounted on the cartridge loading unit 64 via a flexible supply tube 73, and ink of each color can be replenished and supplied from the liquid cartridge 66. It is said that. In order to supply and replenish ink, the cartridge loading section 64 is provided with a supply pump unit 74 that is a liquid feeding means for feeding the liquid in the liquid cartridge 66. In the droplet discharge recording apparatus 60, the supply pump unit 74 and each liquid cartridge 66 correspond to the ink tank 18 (see FIG. 8) described above. In the illustrated example, the supply tube 73 is configured by bundling four tubes corresponding to each color (see FIG. 12), and an intermediate portion thereof is provided on the frame 71 via a holding member 73a. It is fixed to the front stay 75. The liquid droplets ejected from the liquid ejection head 10 are recorded (formed) on the recording paper S as an image. The recording paper S is stacked on a paper stacking unit (pressure plate) 76 provided in the paper feeding tray 62, and the recording paper S is fed to the apparatus main body 61 in order to feed the recording paper S from the paper feeding tray 62. A paper section is provided.

  The paper feed unit includes a paper feed roller (half moon roller) 77 and a separation pad 78. The sheet feeding roller 77 is a half-moon-shaped cylindrical member, and a separation pad 78 is provided to face the sheet feeding roller 77. The separation pad 78 is made of a material having a large friction coefficient and is urged toward the paper feed roller 77 side. In this paper feeding unit, the recording paper S can be separated and fed one by one from the paper stacking unit 76 by the paper feeding roller 77 and the separation pad 78. In order to feed the recording paper S fed from the paper feeding unit to the lower side of the liquid ejection head 10, the apparatus main body 61 is provided with a feeding unit.

  The feeding unit includes a guide member 79 that guides the recording paper S, a counter roller 80, a transport guide member 81, and a pressing member 82 having a leading end pressure roller 82a, and the recording paper S is transported by the transport unit. It is fed to a certain conveyor belt 83.

  The conveyance belt 83 is an endless belt, and is looped between the conveyance roller 84 and the tension roller 85 so as to be able to circulate in the belt conveyance direction (refer to the arrow A4 shown in FIG. 12). Yes. The transport belt 83 electrostatically attracts the fed recording paper S and transports the recording paper S to a position facing each nozzle opening 11 (see FIGS. 1 and 2) of the liquid ejection head 10. In order to charge the surface of the conveying belt 83, the apparatus main body 61 is provided with a charging roller 86 as charging means. The charging roller 86 is disposed so as to be in contact with the surface of the conveyance belt 83 and rotates following the rotation of the conveyance belt 83. The apparatus body 61 is provided with a platen guide plate 87 on the back side of the conveyor belt 83. The platen guide plate 87 maintains the flatness of the recording paper S. The platen guide plate 87 is opposed to each nozzle opening 11 (see FIGS. 1 and 2 etc.) of each liquid ejection head 10 so as to correspond to a printing region by each liquid ejection head 10 with a conveyance belt 83 interposed therebetween. It is provided in the position to do.

  Although not shown, the conveyance belt 83 is rotated or circulated in the belt conveyance direction (sub-scanning direction) by rotating the conveyance roller 84 that receives the driving force from the sub-scanning motor via the timing belt. . The apparatus main body 61 is provided with a paper discharge unit on the downstream side of the printing area of the liquid discharge head 10 when viewed in the circulation direction.

  The paper discharge unit includes a separation claw 88, a paper discharge roller 89, and a paper discharge roller 90. The separation claw 88 separates the recording paper S from the conveyance belt 83. The paper discharge tray 63 on which the recording paper S discharged by the paper discharge unit is stacked is positioned below the paper discharge roller 89.

  In the droplet discharge recording apparatus 60, a duplex unit 91 is detachably mounted on the back side of the apparatus main body 61. The duplex unit 91 takes in the recording sheet S returned by the circulation of the conveying belt 83 without being separated from the conveying belt 83 in the paper discharge unit, reverses the recording sheet S, and again connects the counter roller 80 and the conveying belt 83. Paper is fed in between. A manual feed tray 92 is provided on the upper surface of the duplex unit 91.

  In the droplet discharge recording apparatus 60, as shown in FIG. 12, when viewed in the main scanning direction (the extending direction of the main guide rod 69 and the sub guide rod 70), which is the moving direction of the carriage 68, the intermediate portion is the liquid described above. The printing area is formed by the ejection head 10 and both ends thereof are non-printing areas. In both the non-printing areas, a maintenance / recovery mechanism 93 is provided on one side, and an idle discharge receiver 94 is provided on the other side. The idle discharge receiver 94 receives droplets when performing idle discharge in which droplets that do not contribute to recording are discharged in order to discharge liquid that has been thickened during recording or the like. An opening 94a along the direction is provided. Although not shown, the opening 94a communicates with the waste liquid tank.

  The maintenance / recovery mechanism 93 provided in one of the non-printing regions has basically the same configuration as the liquid introduction device 30 described above, and can perform the same operation, that is, the liquid introduction method of the present invention. Has been. For this reason, in the maintenance / recovery mechanism 93, portions having the same configuration are denoted by the same reference numerals as those of the liquid introduction device 30, and detailed description thereof is omitted. The maintenance / recovery mechanism 93 operates under the control of a control unit that comprehensively controls the operation of the droplet discharge recording apparatus 60 (not shown).

  In the maintenance / recovery mechanism 93, the head holding mechanism 32 in the liquid introducing device 30 is constituted by a carriage 68 for printing, and the reversing shaft 31 is constituted by a main guide rod 69 for moving the carriage 68 in the main scanning direction. An empty discharge receiving portion 95 is provided.

  In the maintenance / recovery mechanism 93, the cap reversing unit 39 of the cap holding mechanism 33 causes each cap 19 held by the cap holding unit 37 to be held by the head holding unit 35 of the carriage 68 (head holding mechanism). In the state where the suction space 21 is formed in close contact with the nozzle surface 16a of the droplet discharge head 10, the cap 19 is reversed around the main guide rod 69 following the reversal of the carriage 68. When not in close contact with 16a, the carriage 68 is configured not to follow the reversal of the carriage 68 (see the carriage 68 indicated by a one-dot chain line).

  Further, in the maintenance and recovery mechanism 93, the wiping mechanism for sliding the wiper 22 for wiping the nozzle surface 16a of the droplet discharge head 10 on the nozzle surface 16a of the droplet discharge head 10 held in a downward posture by the carriage 68. 96 is provided. The empty discharge receiving portion 95 provided in the maintenance / recovery mechanism 93 receives the ink removed from the nozzle surface 16a of the droplet discharge head 10 or has increased the viscosity by the wiping process by the wiping mechanism 96 (wiper 22). In order to discharge the liquid droplets, the liquid droplets are received when performing the idle ejection in which the liquid droplets that do not contribute to the recording are ejected. The maintenance / recovery mechanism 93 is configured to discharge and store the ink discharged to each cap 19 or the ink received by the idle discharge receiving portion 95 into a waste liquid tank (not shown).

  In the droplet discharge recording apparatus 60, the recording paper S is separated and fed one by one from the paper feed tray 62 to the feeding unit by the paper feeding unit. The recording sheet S is fed substantially vertically upward by the guide of the guide member 79, sandwiched between the transport belt 83 and the counter roller 80, transported, guided at the leading end by the transport guide member 81, and pressurized at the leading end. The roller 82a is pressed against the conveyance belt 83.

  At this time, a so-called alternating voltage that alternately repeats a positive output and a negative output is applied to the charging roller 86 from an AC bias supply unit of a control unit (not shown), and the conveying belt 83 has an alternating charging voltage. The pattern is charged, that is, plus and minus are alternately charged in a strip shape with a predetermined width in the sub-scanning direction which is the circulation (circulation) direction. When the recording paper S is fed onto the conveyance belt 83 charged alternately with plus and minus, the recording paper S is adsorbed to the conveyance belt 83. For this reason, the recording sheet S is adsorbed to the conveyance belt 83 in an appropriate state by the above-described guidance and pressing by each member and the adsorption force due to charging, and the circulation direction of the conveyance belt 83 by circulation (circulation movement) of the conveyance belt 83. The direction of conveyance is changed by approximately 90 ° along the direction, and is conveyed in the sub-scanning direction and sent to the recording area.

  In this recording area, a control unit (not shown) drives each liquid ejection head 10 in accordance with an image signal while moving the carriage 68 in the main scanning direction, whereby droplets are ejected onto the stopped recording paper S. Thus, an image for one line is recorded. Thereafter, a control unit (not shown) transports the recording paper S by a predetermined amount in the sub-scanning direction, and records the next line. A control unit (not shown) repeats this recording operation. When a recording end signal or a signal that the trailing edge of the recording paper S reaches the recording area is received, the recording operation is ended, and the recording paper S is transferred to the transport belt 83. The paper is discharged to the paper discharge tray 63 by the circulation (circulation) of the paper. Thereby, a desired image can be recorded on a desired recording medium (the recording sheet S fed).

  In this droplet discharge recording device 60, before the start of recording, in the middle of recording, etc., the carriage 68 is appropriately retracted above the empty discharge receiver 94 or above the empty discharge receiver 95 of the maintenance / recovery mechanism 93. Instead, each liquid discharge head 10 is driven to perform an empty discharge operation for discharging ink. Thereby, the stable discharge performance of each liquid discharge head 10 is maintained.

  In the droplet discharge recording device 60, during printing (recording) standby, the carriage 68 is moved above the maintenance / recovery mechanism 93, and the cap surfaces 19 of the liquid discharge heads 10 are capped with the caps 19, respectively. Each nozzle opening 11 (see FIG. 1 and FIG. 2 and the like) is kept in a wet state, thereby preventing ejection failure due to liquid drying in each nozzle opening 11.

  Further, in the droplet discharge recording device 60, a first maintenance operation and a second maintenance operation are set as operations in the liquid introduction device 30. In the first maintenance operation, the liquid introduction method described above is executed.

  On the other hand, in the second maintenance operation, the following operation is executed.

  First, each cap 19 is brought into intimate contact with the nozzle surface 16a of each droplet discharge head 10 in a downward posture to form a suction space 21.

  Thereafter, the ink is pumped from the ink tank 18 to each common liquid chamber 13 while the droplet discharge heads 10 are in the downward posture, and the suction space 21 is decompressed by the suction device 20. As a result, an ink flow from the common liquid chamber 13 to the suction space 21 through the pressure generation chambers 12 and the nozzle openings 11 is formed while the droplet discharge heads 10 are in the downward posture. This is a flow path cleaning process. In this flow path cleaning step, since ink is sucked from each nozzle opening 11 (referred to as “nozzle suction” or “head suction”), for example, a recovery operation for discharging the thickened liquid from each nozzle opening 11 is performed. Will be done.

  After this flow path cleaning step, each cap 19 is separated downward from the nozzle surface 16a of each droplet discharge head 10 in the downward posture, so that the common liquid chamber 13 is slightly smaller than the atmosphere around the droplet discharge head 10. Use low pressure. This is a separation step. In the present embodiment, in addition to this, when the cap 19 is separated from the nozzle surface 16a, suction by the suction device 20 is started at the same time or immediately before being separated. By this separation step, it is possible to reliably prevent the periphery from being stained with the ink stored in the cap 19.

  After the separation of the caps 19, the wiper mechanism 96 wipes the nozzle surface 16 a of the droplet discharge head 10 with the wiper 22. This is the cleaning process. By this cleaning process, even if ink adheres to the nozzle surface 16a of the droplet discharge head 10, it is completely removed. In the liquid droplet ejection head 10, the common liquid chamber 13 is slightly lower in pressure than the atmosphere around the liquid droplet ejection head 10, so that a meniscus is formed by the ink filled in each nozzle opening 11. Is done.

  As described above, the second maintaining operation is performed in each droplet discharge head 10 from the common liquid chamber 13 to the plurality of pressure generation chambers 12 communicating with the same and the nozzle openings 11 (ink flow paths). In order to prevent the occurrence of clogging or the like and maintain each droplet discharge head 10 in an appropriate state, it is executed more simply than the first maintenance operation.

  Therefore, in the droplet discharge recording device 60, for example, the second maintenance operation is appropriately executed to maintain the state of each droplet discharge head 10 when the normal recording operation is performed a predetermined number of times. The first maintenance operation can be selectively executed for refreshing each droplet discharge head 10 such as when the dirt becomes severe and when newly introducing ink into each droplet discharge head 10. By setting, it is possible to improve usability. This is because the second maintenance operation can be easily performed, and therefore, by appropriately setting for maintaining the state of each droplet discharge head 10, a good state of each droplet discharge head 10 is achieved. This is because it can be maintained appropriately. On the other hand, the first maintenance operation is more complicated and requires more time than the second maintenance operation, but is mixed into the ink in the common liquid chamber 13 and each pressure generation chamber 12 of each droplet discharge head 10. The bubbles that are present can be effectively removed. For this reason, when the contamination becomes severe, it may be caused by air bubbles being mixed in the ink in the common liquid chamber 13 and the pressure generation chamber 12 of each droplet discharge head 10, When new ink is introduced into the ejection head 10, it is considered that bubbles are likely to be mixed into the introduced ink. Therefore, the first maintenance operation can be set to be selectively executable. This is because the user can use the droplet discharge recording apparatus 60 in a more comfortable and better state.

  Further, in the liquid droplet ejection recording apparatus 60, when the caps 19 are not in close contact with the liquid introduction apparatus 30, only the liquid droplet ejection heads 10 are inverted while the caps 19 are disposed below and directed upward. Since the posture can be set, the maintenance of the nozzle surface 16a of the droplet discharge head 10 can be easily performed.

  Here, in the above-described embodiment, as an example of the droplet discharge recording apparatus equipped with the liquid introduction apparatus (maintenance / recovery mechanism 93) capable of executing the liquid introduction method according to the present invention, the carriage 68 is mainly used in the recording operation. Although the serial type droplet discharge recording apparatus 60 (see FIGS. 10 to 12) moved in the scanning direction is shown, for example, in a head stationary type droplet discharge recording apparatus 60 ′ as shown in FIG. 13 and FIG. It may be present and is not limited to the above-described embodiments. The head stationary type droplet discharge recording apparatus 60 'will be described.

  In the head stationary type droplet discharge recording apparatus 60 ′ shown in FIGS. 13 and 14, each droplet discharge head 10 ′ is basically fixed, and each fixed droplet discharge head 10 ′ is fixed. The recording sheet S adsorbed on the conveyance belt 83 ′ is conveyed. In this droplet discharge recording apparatus 60 ′, although not shown, the alignment direction of the nozzle openings (see reference numeral 11 in FIG. 2 and the like) of each droplet discharge head 10 ′ is orthogonal to the circulation direction of the transport belt 83 ′. The circulation direction of the conveyance belt 83 ′ is the main scanning direction. For this reason, the extension range seen in the alignment direction of each nozzle opening of each droplet discharge head 10 ′ becomes a recordable range on the recording sheet S conveyed on the conveyance belt 83 ′.

  In addition to the general configuration as described above, in the droplet discharge recording apparatus 60 ′ according to the present invention, each droplet discharge head 10 ′ is individually held by the reversing mechanism 50. The reversing mechanism 50 includes a head support bracket 51 that can be reversed around the rotation shaft 84a of the conveyance roller 84 ′ for circulation of the conveyance belt 83 ′, and a reversal that reverses the head support bracket 51 around the rotation shaft 84a. A drive unit (not shown) and a link mechanism unit 52 provided near the tip of the head support bracket 51 and connecting the head support bracket 51 and the droplet discharge head 10 'are included. In a normal state (see the reversing mechanism 50 indicated by a solid line in FIG. 15), the reversing mechanism 50 holds the droplet discharge head 10 ′ in a state where the recording operation can be performed, that is, the droplet discharge head 10 ′ is in a downward posture. The droplet discharge head 10 ′ is held so as to be in a positional relationship that allows ink to be appropriately discharged from the droplet discharge head 10 ′ toward the recording sheet S that is appropriately adsorbed by the conveyance belt 83 ′. ing. The link mechanism 52 of the reversing mechanism 50 maintains the downward attitude of the droplet discharge head 10 ′ so that the interval between the droplet discharge head 10 ′ and the transport belt 83 ′ changes. Can be moved in parallel (see the droplet discharge head 10 'shown by the two-dot chain line in FIG. 15). Although not shown, the reversing mechanism 50 is controlled by a controller that comprehensively controls the operation of the droplet discharge recording device 60 ′, and the parallel movement and reversal drive unit (not shown) of the droplet discharge head 10 ′ by the link mechanism 52. The reversal of the head support bracket 51 is controlled.

  Further, in the droplet discharge recording apparatus 60 ′, each cap 19 ′ is provided corresponding to each droplet discharge head 10 ′, and each cap 19 ′ is individually held by the cap holding mechanism 53.

  Each cap holding mechanism 53 is reversible around the rotation shaft 84a of the transport roller 84 ', and a cap support bracket 54 that holds each cap 19', and a reversal drive that reverses the cap support bracket 54 about the rotation shaft 84a. Part (not shown). Each cap holding mechanism 53 reverses the cap support bracket 54 by a reversing drive unit (not shown) so that the cap 19 'held between the droplet discharge head 10' and the transport belt 83 ' Around the rotation axis 84a from the position where there is no gap (see the cap 19 'indicated by the solid line in FIG. 13) to between the droplet discharge head 10' and the transport belt 83 '(see the cap 19' indicated by the two-dot chain line in FIG. Can be reversed. Further, when the held cap 19 'is reversed, the suction space 21 is maintained with the corresponding droplet discharge head 10' and the cap 19 'in cooperation with the reversing mechanism 50 as will be described later. The caps 19 ′ can follow the reversal of the droplet discharge head 10 ′ by the reversing mechanism 50. Since the cap 19 ′ held by the cap holding mechanism 53 has the same configuration as the cap 19 described above, a detailed description thereof will be omitted.

  The operation of the droplet discharge recording apparatus 60 'will be described with reference to FIG. In the droplet discharge recording apparatus 60 ′, the operation of each reversing mechanism 50 and each cap holding mechanism 53 corresponding thereto is the same, so in FIG. 15, the reversing mechanism closest to the rotation shaft 84a of the transport roller 84 ′. Only 50 and the cap holding mechanism 53 corresponding thereto are described, and the operation will be described, and the other description will be omitted.

  In the droplet discharge recording apparatus 60 ′, when the maintenance / recovery operation (including the first maintenance operation and the second maintenance operation described above) of each droplet discharge head 10 ′ is performed, first, the head support bracket 51 of the reversing mechanism 50 is moved. By the link mechanism 52, the droplet discharge head 10 'is translated in the upward direction, that is, in the direction away from the transport belt 83' (see FIG. 15A).

  Thereafter, the cap support bracket 54 of the cap holding mechanism 53 is reversed to move the cap 19 'onto the transport belt 83' (see FIG. 15B).

  Thereafter, the droplet discharge head 10 ′ is translated downward by the link mechanism 52 of the head support bracket 51 of the reversing mechanism 50, that is, in the direction approaching the transport belt 83 ′, and is positioned on the transport belt 83 ′. The nozzle surface 16a (see FIG. 5 and the like) of the droplet discharge head 10 ′ is pressed against the cap 19 ′ to form the suction space 21 (see FIG. 5 and the like) (see FIG. 15C). For this reason, in the droplet discharge recording apparatus 60 ′, the link mechanism portion 52 and the cap holding mechanism 53 of the head support bracket 51 of the reversing mechanism 50 are capably displaceable with respect to the droplet discharge head held by the head holding means. It functions as a sealing member holding means for holding (sealing member).

  Thereafter, in the first maintenance operation, the head support bracket 51 of the reversing mechanism 50 and the cap support bracket 54 of the cap holding mechanism 53 are reversed so that the suction space 21 (see FIG. 5 and the like) is formed. While maintaining the position, the droplet discharge head 10 ′ is set in an upward posture (see FIG. 15D). While maintaining the state in which the suction space 21 (see FIG. 5 and the like) is formed, the operation of setting the droplet discharge head 10 ′ in the upward position reverses all the droplet discharge heads 10 ′ and the cap 19 ′ at the same time. Alternatively, it may be individually reversed for each combination of the droplet discharge head 10 ′ and the cap 19 ′ that make a pair (depending on the relationship for forming the suction space 21). In the subsequent operation, similar to the above-described maintenance / recovery mechanism 93 (liquid introduction device 30), the bubble removing process is performed, the reversing process is performed, and the separating process is performed. The bubble removing process, the reversing process, and the separating process may also be performed for all the droplet discharge heads 10 'and caps 19' at the same time. For each combination of the droplet discharge head 10 'and the cap 19' that make a pair, (Depending on the relationship for forming the suction space 21) may be performed individually. Moreover, it is good also as a structure which performs a wiping process similarly to the above-mentioned maintenance recovery mechanism 93 (liquid introduction apparatus 30).

  Further, when the second maintenance operation is executed, the flow path cleaning process is performed without inverting the droplet discharge head 10 ′ and the cap 19 ′, similarly to the above-described maintenance recovery mechanism 93 (liquid introduction device 30). And performing a reversal process and a separation process. Moreover, it is good also as a structure which performs a wiping process similarly to the above-mentioned maintenance recovery mechanism 93 (liquid introduction apparatus 30).

  As described above, the droplet discharge recording device 60 ′ can obtain the same effects as those of the droplet discharge recording device 60 described above.

  Further, in the droplet discharge recording apparatus 60 ′, the state in which the suction space 21 is formed is maintained by inverting each droplet discharge head 10 ′ and each cap 19 ′ around the rotation shaft 84a of the transport roller 84 ′. Since each droplet discharge head 10 'is changed from the downward posture to the upward posture to perform the first maintenance operation, the first maintenance operation is performed while reducing a new configuration for the first maintenance operation. The first maintenance operation can be performed by retracting the droplet discharge head 10 ′ and each cap 19 ′ from the conveyance belt 83 ′. For this reason, it can prevent that conveyance belt 83 'gets dirty with execution of the 1st maintenance operation.

  Furthermore, since the droplet discharge recording apparatus 60 ′ can perform the first sustain operation and the second sustain operation for each droplet discharge head 10 ′, the first discharge operation is appropriately performed according to the state of each droplet discharge head 10 ′. The maintenance operation and the second maintenance operation can be performed, and usability can be further improved.

  Here, in the above-described droplet discharge recording apparatus 60 ′, four caps 19 ′ are provided to correspond to the four droplet discharge heads 10 ′, and four cap holding mechanisms 53 are provided. The cap and the cap holding mechanism can be single. In this case, the cap holding mechanism may be configured to be able to move in parallel along the transport belt to the position where the four droplet discharge heads exist after inverting the cap onto the transport belt. Thus, if it is set as the structure which has a single cap and a cap holding | maintenance mechanism, a droplet discharge recording device can be reduced more in size.

  In the above-described embodiment, the droplet discharge head capable of carrying out the present invention is different in the direction of the discharge port (nozzle opening 11) with respect to the extending direction of the ink flow path (each pressure generation chamber 12). Although the side shooter method is used, an edge shooter method in which the shape from the ink flow path to the discharge port is linear may be used, and the present invention is not limited to the above-described embodiment. Hereinafter, the edge shooter method and the side shooter method will be described.

  An example of the edge shooter type droplet discharge head 101 is shown in FIG.

  The droplet discharge head 101 includes a substrate 1011 having a discharge energy generator 17 (electrodes for applying a discharge signal to the generator and a protective layer provided on the generator as needed are omitted). The side wall of the flow path 1012 and the wall material 1014 constituting the orifice 1013 and the top plate 1015 constituting the cover of the flow path 1012 are laminated.

  In the liquid droplet ejection head 101, a recording signal is ejected from a liquid chamber (not shown) in which ink is stored into a flow path 1012 and an ejection energy generator 17 outputs a recording signal through an electrode (not shown). Is applied to the ink in the flow path 1012 above the discharge energy generator 17 (discharge energy action portion). Thereby, ink is ejected from the orifice 1013 as ink droplets. The ejected ink droplets are attached to a recording material such as paper fed in front of the orifice 1013.

  In an edge shooter type droplet discharge head such as the droplet discharge head 101, it is extremely easy to miniaturize each part with high accuracy, to increase the number of orifices, and to reduce the overall size. Moreover, it has the advantage that it is rich in mass productivity. On the other hand, there is a limit to the response frequency and ink droplet flight speed when ejecting ink droplets. In addition, bubbles are generated in the ink due to the heat generated by the electrothermal conversion element. The discharge energy generator 17 is affected by an impact when the bubbles contract due to a decrease in temperature and disappear in the vicinity of the discharge energy generator 17. Gradually destroyed. This phenomenon is called a cavitation phenomenon and is remarkable in the edge shooter system. For this reason, the life of the edge shooter type droplet discharge head is relatively short.

  An example of a side shooter type droplet discharge head 102 is shown in FIG.

  In the droplet discharge head 102, an orifice 1013 ′ is provided on a top plate 1015 ′ corresponding to the top plate 1015 of the droplet discharge head 101 described above, and the tip portion of the flow path 1012 ′ (the orifice 1013 of the droplet discharge head 101). The portion corresponding to (3) is closed with a top plate 1015 ′. In this droplet discharge head 102, as indicated by a broken line L, the direction of ink flow toward the discharge energy acting portion in the flow path 1012 ′ and the opening center axis of the orifice 1013 ′ are orthogonal to each other.

  In the side shooter type liquid droplet discharge head such as the liquid droplet discharge head 102, the energy from the discharge energy generator 17 is more efficiently formed and the ink droplets are formed compared to the edge shooter type liquid droplet discharge head. It can be converted into flight kinetic energy. In addition, there is a structural advantage that the meniscus can be quickly restored by supplying ink. This advantage is particularly effective when a heating element is used as the discharge energy generator. Furthermore, the cavitation phenomenon which is a problem in the edge shooter method can be avoided. This is because in the side shooter system, when bubbles grow, the bubbles reach the orifice 1013 ′ and the bubbles communicate with the atmosphere, so that the bubbles do not contract due to a temperature drop. For this reason, the side shooter type droplet discharge head has an advantage of a long life.

  In the above-described embodiment, the droplet discharge head 10 is provided with the nozzle opening 11 having an inner diameter smaller than the inner diameter at the tip of each pressure generating chamber 12 (ink channel) communicating with the common liquid chamber 13. Although it is configured, it is only necessary that one end of each pressure generating chamber 12 communicates with the outside in order to eject ink droplets from each pressure generating chamber 12, and the present invention is not limited to the above-described embodiment.

  Further, in the above-described embodiment, the droplet discharge recording device 60 and the droplet discharge recording device 60 ′, which are printers, are shown as the image forming apparatus according to the present invention. In addition, the present invention can also be applied to a liquid droplet ejection head or liquid droplet ejection apparatus that ejects a liquid other than ink, such as a DNA sample, a resist, or a pattern material, or an image forming apparatus including these. .

  The present invention has been described in detail based on the embodiments. However, the present invention is not limited to this specific configuration, and design changes that do not depart from the spirit of the present invention are included in the technical scope of the present invention.

It is a disassembled perspective view which shows typically the droplet discharge head suitable for implementation of the liquid introduction method which concerns on this invention. It is a bottom view which shows typically a droplet discharge head. It is sectional drawing obtained along the II line of FIG. It is sectional drawing obtained along the II-II line | wire of FIG. It is explanatory drawing for description of the liquid introduction method which shows a droplet discharge head and a cap in a cross section. It is a typical perspective view which shows a cap. It is explanatory drawing for description of the liquid introduction method, (a) shows the state which formed the suction space, (b) shows a mode that the bubble removal process was started, (c) completed the bubble removal process (D) shows the state of the inversion process, (e) shows the state of the separation process, and (f) shows the state of the wiping process. It is explanatory drawing which shows typically the structure of the liquid introduction apparatus which can implement the liquid introduction method which concerns on this invention. It is explanatory drawing seen from the arrow A1 side shown in FIG. 1 is a schematic perspective view showing a droplet discharge recording apparatus capable of performing a liquid introduction method according to the present invention. FIG. 3 is a schematic explanatory view of the inside of the droplet discharge recording apparatus according to the present invention as viewed in a main scanning direction to be described later in order to explain the internal configuration. It is schematic explanatory drawing seen along arrow A 2 shown in FIG. FIG. 3 is a schematic explanatory diagram for explaining a configuration of a head stationary type droplet discharge recording apparatus capable of performing the liquid introduction method according to the present invention. It is the schematic explanatory drawing seen along arrow A5 shown in FIG. 4A and 4B are explanatory diagrams for explaining the operation of the head stationary type droplet discharge recording apparatus according to the present invention. FIG. 5A shows a state in which the droplet discharge head is translated upward, and FIG. (C) shows a state in which a suction space is formed, and (d) shows a state in which the droplet discharge head and the cap are reversed while the suction space is formed. ing. It is explanatory drawing which shows an example of the edge shooter type droplet discharge head. It is explanatory drawing which shows an example of the droplet discharge head of a side shooter system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 10 'Droplet discharge head 11 Nozzle opening 12 Pressure generating chamber 13 Common liquid chamber 16a Nozzle surface 17 Discharge energy generating body 18 Ink tank 19, 19' (as a liquid introduction means) Cap 20 (As a sealing member) Suction device (as suction means) 21 Suction space 22 Wiper (as wiping member) 30 Liquid introduction device 34 Head reversing part (as head displacement means) 35 Head holding part 37 (as head holding means) (Sealing member) Cap holding portion (as holding means) 38 Cap parallel moving portion (as sealing member holding means) 39 Cap reversing portion (as sealing member displacement means) 40a Arm (as wiping member holding means and wiping member moving means) Unit 40b main body unit 60 (as wiping member moving means) 60, 60 'droplet discharge recording device 68 The axis of rotation of Tsu di 69 main guide rod 84a conveyance roller

Claims (18)

A plurality of nozzle openings for discharging droplets, a plurality of pressure generating chambers provided individually corresponding to the nozzle openings, and a liquid can be introduced and stored in each of the plurality of pressure generating chambers. A liquid introduction method into a droplet discharge head comprising a common liquid chamber and a discharge energy generator provided corresponding to each pressure generation chamber in order to discharge a droplet from each pressure generation chamber,
A sealing member that can cover the nozzle openings comprehensively by disposing the droplet discharge head so that the nozzle openings are positioned vertically above the pressure generation chambers and the common liquid chamber; A suction space is formed by the nozzle surface and the sealing member in airtight contact with the nozzle surface provided with each nozzle opening, and the pressure of the suction space is made lower than the pressure of the common liquid chamber. A bubble removing step for forming a flow of liquid from the common liquid chamber to the suction space;
The liquid droplet ejection head is inverted so that each nozzle opening faces downward in the vertical direction while the sealing member is in contact with the nozzle surface in a state where the suction space and the common liquid chamber are filled with liquid. Reversing process to
And a separation step of separating the sealing member from the nozzle surface in a state in which each nozzle opening of the droplet ejection head faces a vertically downward direction. Liquid introduction method.   In the reversing step, the pressure in the suction space and the pressure in the common liquid chamber are made equal, and the nozzle openings face downward in the vertical direction while the sealing member is kept in contact with the nozzle surface. The method for introducing a liquid into a droplet discharge head according to claim 1, wherein the droplet discharge head is reversed.   3. The liquid according to claim 1, wherein, in the bubble removing step, the pressure of the suction space is made lower than the pressure of the common liquid chamber by pumping the liquid to the common liquid chamber. A method for introducing liquid into the droplet discharge head.   3. The droplet discharge head according to claim 1, wherein, in the bubble removing step, the pressure in the suction space is made lower than the pressure in the common liquid chamber by reducing the pressure in the suction space. Liquid introduction method.   The pressure in the suction space is made lower than the pressure in the common liquid chamber by depressurizing the suction space while pumping liquid into the common liquid chamber in the bubble removing step. A method for introducing a liquid into the droplet discharge head according to claim 2.   The wiping step of wiping the nozzle surface with a wiping member is performed after the separation step in a state in which each nozzle opening of the droplet discharge head maintains a posture in which the nozzle opening faces downward in the vertical direction. The method for introducing a liquid into the droplet discharge head according to any one of claims 1 to 5. A plurality of nozzle openings for discharging droplets, a plurality of pressure generating chambers provided individually corresponding to the nozzle openings, and a liquid can be introduced and stored in each of the plurality of pressure generating chambers. A liquid introducing device to a droplet discharge head comprising a common liquid chamber and a discharge energy generator provided corresponding to each pressure generation chamber to discharge a droplet from each pressure generation chamber,
A head holding means capable of holding the droplet discharge head;
The droplet discharge head held by the head holding means has an upward posture in which the nozzle openings are positioned vertically above the pressure generating chambers and the common liquid chamber, and the nozzle openings are vertically downward. A head displacement means for displacing between a downward posture facing the
Liquid introducing means capable of pumping liquid to the common liquid chamber of the droplet discharge head held by the head holding means;
The nozzle openings of the droplet discharge head can be covered comprehensively, and the droplet discharge head can be brought into airtight contact with the nozzle surface provided with the nozzle openings. A sealing member that can form a suction space in cooperation with the nozzle surface by means of an abutment;
Sealing member holding means for holding the sealing member displaceably with respect to the droplet discharge head held by the head holding means to form the suction space;
Sealing member displacing means capable of following the displacement of the liquid droplet ejection head by the head displacing means, with the sealing member held by the sealing member holding means forming the suction space;
A suction means capable of depressurizing the suction space;
The pressure of the suction space formed by bringing the sealing member into contact with the nozzle surface of the droplet discharge head in the upward posture is made lower than the pressure of the common liquid chamber, and the suction space from the common liquid chamber Perform a bubble removal process to form a liquid flow to
Inversion with the droplet discharge head turned downward by inverting the droplet discharge head while the sealing member is in contact with the nozzle surface while the suction space and the common liquid chamber are filled with liquid. Perform the process,
An apparatus for introducing a liquid into a droplet discharge head, wherein a separation step of separating the sealing member from the nozzle surface is performed in a state in which the downward posture of the droplet discharge head is maintained.   In the reversing step, the pressure in the suction space is made equal to the pressure in the common liquid chamber, and the liquid droplet ejection head is reversed with the sealing member kept in contact with the nozzle surface. The apparatus for introducing a liquid into a liquid droplet ejection head according to claim 7, wherein the liquid is ejected downward.   The said bubble removal process WHEREIN: The said liquid introduction means pumps a liquid into the said common liquid chamber, The pressure of the said suction space is made lower than the pressure of the said common liquid chamber, The Claim 7 or Claim characterized by the above-mentioned. 9. A liquid introduction device for a droplet discharge head according to 8.   The said bubble removal process WHEREIN: The said suction means depressurizes the said suction space, The pressure of the said suction space is made lower than the pressure of the said common liquid chamber, The Claim 7 or Claim 8 characterized by the above-mentioned. Liquid introduction device to the droplet discharge head.   In the bubble removing step, the pressure of the suction space is made lower than the pressure of the common liquid chamber by the suction means depressurizing the suction space while the liquid introduction means pumps the liquid to the common liquid chamber. The apparatus for introducing a liquid into a droplet discharge head according to claim 7 or 8, wherein A liquid introduction device to a droplet discharge head according to any one of claims 7 to 11,
Further, a wiping member holding means for holding a wiping member capable of wiping the nozzle surface by sliding on the nozzle surface;
Wiping member moving means for moving the wiping member held by the wiping member holding means so as to wipe the nozzle surface of the droplet discharge head in a downward posture;
An apparatus for introducing a liquid into a droplet discharge head, wherein a wiping step of wiping the nozzle surface with the wiping member is performed after the separation step while the droplet discharge head is maintained in a downward posture. A serial type liquid droplet ejection recording apparatus comprising: the liquid introduction device for the liquid droplet ejection head according to any one of claims 7 to 12; and the liquid droplet ejection head.
The head holding means is a carriage for moving the droplet discharge head in the main scanning direction when printing by discharging droplets from the nozzle openings of the droplet discharge head;
The liquid droplet ejection recording apparatus, wherein the head displacing means rotates the carriage around a guide rod for moving the carriage. A stationary type droplet discharge recording apparatus comprising: the liquid discharge device to the droplet discharge head according to any one of claims 7 to 12; and the droplet discharge head.
The head displacing means rotates the droplet discharge head about a rotation axis of a conveyance roller for rotating a conveyance belt that conveys a recording medium recorded by droplets ejected from the droplet ejection head. A droplet discharge recording apparatus characterized by the above. In the liquid introduction device, apart from the first maintenance operation for performing the bubble removal step, the inversion step, and the separation step,
The pressure of the suction space formed by bringing the sealing member into contact with the nozzle surface of the droplet discharge head in the downward posture is made lower than the pressure of the common liquid chamber, so that the suction space is extended from the common liquid chamber. The liquid droplet ejection recording apparatus according to claim 13 or 14, wherein a second maintenance operation for performing a flow path cleaning step for forming a liquid flow into the liquid can be performed.   16. The droplet discharge recording apparatus according to claim 15, wherein the second maintenance operation is set as a normal maintenance operation that is appropriately executed to maintain the function of the droplet discharge head.   16. The first maintaining operation is performed to fill the liquid droplet ejection head that is not filled with a printing liquid for printing with the printing liquid. Droplet discharge recording apparatus. The liquid droplet ejection recording apparatus according to claim 15, wherein the first maintaining operation is executed to recover the function of the degraded liquid droplet ejection head.

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