JP2009018519A - Image recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image recorder which does not need a moving mechanism and a positioning mechanism having a high accuracy of positioning in the Z direction of a maintenance unit. <P>SOLUTION: The pressure fed from a piping B34, when the maintenance unit 13 is at its retracting position, is the same pressure as an atmospheric pressure, and a sub-base 53 is lowered downward together with an air spring 51 shrunk in a natural state. At the cleaning operation, a maintenance base 36 is moved to the maintenance position together with the maintenance unit 13. The pressure higher than the atmospheric pressure is fed from the piping B34, the air spring 51 is extended in a Z direction, the sub-base 53 is raised, and the upper part of a wiping part 37, a sucking part 38 or an upper part of a cap part 60 is set to the position higher than a nozzle plate surface 24. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an inkjet image recording apparatus having a simple maintenance mechanism.

Recording by an inkjet image recording apparatus performs desired recording by landing a small amount of ink ejected from a minute nozzle hole provided in an inkjet head on a recording medium.
As an inkjet image recording apparatus, for example, a piezo method using a piezoelectric element and a thermal method using a heating element are known.

  In such an ink jet head of an image recording apparatus, foreign matter such as dust or paper dust or thickened ink adheres to the nozzle plate surface in which the nozzle holes are formed, adversely affecting the ejection performance, and printing quality. There is a problem of lowering.

  Therefore, conventionally, a wiping function that removes dust and paper powder adhering to the nozzle plate surface by rubbing the nozzle plate surface with a wipe blade formed of an elastic member, excess ink on the nozzle plate surface, and thickened ink There has been proposed an image recording apparatus provided with a maintenance unit that maintains the nozzle plate surface and recovers the print quality by a suction function for sucking out the ink.

  In addition, an image recording apparatus having a maintenance unit having a capping function for reducing the viscosity increase of ink due to drying by capping the nozzle plate surface of the inkjet head so as to shield it from outside air when the recording operation is not performed has been proposed. Yes.

  Since such a maintenance unit hinders the recording operation, the maintenance unit is disposed at a position separated from the recording medium conveyance path. When performing the wiping operation, the suction operation, or the capping operation, the maintenance unit or the head holder that supports the inkjet head moves relatively.

For example, in Patent Document 1, when the recording apparatus is in a standby state, the nozzle surface of the recording head is sealed with a cap. From this state, when performing the cleaning operation of the recording head, the head holder that holds the recording head is raised. Then, when the head holder reaches the cleaning position where the cleaning operation is performed, the ascent is stopped and the head holder is stopped. Thereafter, the wipe blade is moved to a position facing the nozzle plate surface of the recording head to perform a cleaning operation. When recording an image from the standby state, the head holder is first moved upward to retract the cap and wipe blade. When the cap and wipe blade are retracted, the head holder is moved downward, stops moving at the recording position, and remains stationary.
JP 2004-330546 A

  However, in Patent Document 1, the head holder must be moved to each of a cap position for capping the nozzle surface of the recording head and a wiper position for wiping the nozzle surface with a wipe blade. Here, the cleaning performance (for example, the presence or absence of wiping unevenness) and the capping performance (for example, the presence or absence of leakage with outside air) are the positional accuracy with respect to the contact direction (hereinafter referred to as the Z direction) between the maintenance unit and the nozzle plate surface of the inkjet head. It depends on. For this reason, in order to ensure good cleaning performance and capping performance in Patent Document 1, the accuracy of the moving mechanism that moves the head holder is increased, or the accuracy of the positioning mechanism that positions the recording head and the maintenance unit is increased. Must be raised.

  Therefore, in order to solve the above-described problems, the present invention provides an image recording apparatus that does not require a highly accurate moving mechanism or positioning mechanism for positioning the maintenance unit in the Z direction with respect to the nozzle plate surface that satisfies the cleaning performance and the capping performance. The purpose is to provide.

  In order to solve the above problems, an image recording apparatus of the present invention includes an inkjet head having a nozzle plate in which nozzle holes for discharging ink toward a recording medium are formed, a maintenance unit that performs maintenance of the nozzle plate, and an arbitrary A pressure supply unit for supplying the air pressure to the maintenance unit, and the maintenance unit has a pressure movable unit, and the pressure movable unit is configured to maintain the nozzle plate by the air pressure supplied from the pressure supply unit. It moves to the maintenance position which performs.

  According to the present invention, it is possible to provide an image recording apparatus that does not require a highly accurate moving mechanism or positioning mechanism for positioning the maintenance unit in the Z direction with respect to the nozzle plate surface that satisfies the cleaning performance and the capping performance.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 1 (a) shows a side view of the image recording apparatus in the first embodiment of the present invention, and FIG. 1 (b) shows a top view thereof. FIG. 1B is a perspective view of FIG. 1A from the top in order to show the arrangement of the head unit and the maintenance unit.

  In addition, arrows X, Y, and Z shown in FIGS. 1A and 1B respectively indicate a recording medium conveyance direction (sub-scanning direction of image recording) and a width direction of the recording medium (main scanning direction of image recording). , And upward directions orthogonal to those directions. The same applies to other figures following FIG. 2 described later.

  As shown in FIG. 1A, the image recording apparatus 1 includes a head unit 10, an ink bottle 11, a base 12, a maintenance unit 13, a recording medium recovery unit 14, a recording medium 15, a recording medium transport unit 16, and a recording unit. The medium supply unit 17 and the head holder 18 are configured.

  The recording medium supply unit 17 feeds the recording medium 15 to the recording medium transport unit 16. The recording medium conveyance unit 16 conveys the recording medium 15 to a position facing the head unit 10 by rotating the belt 19. Further, a mechanism is provided that can vary the distance between the head unit 10 and the recording medium 15 conveyed by the recording medium conveying unit 16 according to the thickness of the recording medium 15 to be used. The head unit 10 ejects ink from nozzle holes formed on the nozzle plate surface of the inkjet head 21 and records an image on the recording medium 15 conveyed by the recording medium conveying unit 16.

The surface of the nozzle plate is provided with a liquid repellent layer having high water repellency for water-based inks and high oil repellency for oil-based inks in order to maintain ink ejection performance.
In the present embodiment, oil-based ink is used, a polyimide film is used for the nozzle plate, and a fluorine coating having high oil repellency is applied to the surface of the nozzle plate.

The recording medium recovery unit 14 recovers the recording medium 15 on which an image is recorded by the head unit 10.
The base 12 is fixed to the housing of the image recording apparatus 1. The base 12 supports a head holder 18 and a maintenance unit 13. The head holder 18 supports the head unit 10.

The maintenance unit 13 performs maintenance on the nozzle plate surface formed on the ink jet head of the head unit 10.
During the recording operation, the maintenance unit 13 is retracted to a position separated from the position facing the head holder 18 in the Y direction, as shown in FIG. 1B.

2 (a) and 2 (b) are diagrams showing the movement operation of each related part when the maintenance unit 13 performs the cleaning operation.
As shown in FIG. 2A, when the maintenance unit 13 performs the cleaning operation, first, the recording medium transport unit 16 descends downward in the Z direction indicated by the arrow a and is formed on the inkjet head 21. The distance between the nozzle plate surface and the conveyance surface of the belt 19 that conveys the recording medium is widened.

  Subsequently, the maintenance unit 13 slides as shown by an arrow b while being supported by the base 12 to a position facing the nozzle plate surface of the plurality of inkjet heads 21 arranged. Thereby, the maintenance unit 13 performs the cleaning operation of the nozzle plate surface.

  Although not particularly shown, the image recording apparatus 1 includes an ink supply unit that supplies ink from the ink bottle 11 to the head unit 10, a pressure supply unit that supplies a predetermined pressure to the maintenance unit 13, and the pressure. A piping section for transmission and an electrical unit for controlling the image recording apparatus 1 and performing image processing are provided.

FIG. 3 is a top view of the head unit 10 of the image recording apparatus 1. FIG. 3 is a view of the arrangement of the head unit 10 as seen through the base 12 and the head holder 18 of FIG. 1 from above.
As shown in FIG. 3, the head unit 10 has a staggered arrangement of six ink-jet heads 21 (21-1 to 21-6) for each of the four colors (black, cyan, magenta, yellow) to be ejected. Arranged in a shape.

  By arranging the six inkjet heads 21 in a staggered manner in this way, the nozzle holes formed in the nozzle plate surface of each inkjet head 21 are continuously arranged in the direction of the print width W. It will be. That is, it is possible to perform continuous printing between the six inkjet heads 21.

As a result, the line head 22 having a printing width W of approximately 300 mm can be configured.
In this example, four sets of line heads 22 for four colors are arranged in parallel. In addition, with this configuration, the single-sided recording of the recording medium 15 is completed only by the recording medium 15 being transported once to the position facing the head unit 10.

  When performing double-sided recording, the recording medium 15 is reversed upside down by a recording medium reversing unit (not shown), and the reversed recording medium 15 is transported to a position facing the head unit 10 again. Thereby, double-sided recording is performed.

In this embodiment, the maintenance unit 13 is retracted in the Y direction, which is a horizontal direction perpendicular to the recording medium conveyance direction, but the retracting direction is not limited to this.
4A and 4B are diagrams showing another example of the retracting direction of the maintenance unit 13. In this example, while the image recording apparatus 1 is performing the recording operation, the maintenance unit 13 is retracted to a position spaced in the X direction from the position facing the head unit 10 as shown in FIG. is doing.

  In this example, the maintenance unit 13 is supported by grooves 23 formed on both side surfaces of the base 12 in the Y direction, and is guided by the grooves 23 to move between the retracted position and the maintenance position. The groove 23 is high in the Z direction at the retracted position and is low in the Z direction at the maintenance position.

  As a result, during the cleaning operation, the maintenance unit 13 is guided by the groove 23, and the respective ink jets 21 (FIG. 4B) shown in FIG. 4B from the retracted position that does not interfere with the conveyance of the recording medium shown in FIG. 3) and moves to a maintenance position lower in the Z direction than the nozzle plate surface, that is, a position facing the nozzle plate surface while sliding as indicated by an arrow c. Then, a cleaning operation is performed.

  5A to 5E show the head unit 10 and the maintenance unit when the image recording apparatus 1 according to the first embodiment is viewed from the downstream side in the recording medium conveyance direction (in the direction of arrow A in FIG. 1A). FIG.

6A and 6B are diagrams for explaining the configuration and operation of the wiping portion and the suction portion of the maintenance unit 13.
As shown in FIG. 5 (a), the maintenance unit 13 uses the wiper 37, the suction unit 38, and the pressure supply unit (not shown) for cleaning the nozzle plate surface 24 to generate the pressure generated by the wiper 37 and the suction unit. The pipe A32, the pipe B34, and the pipe B34 are formed for transmission to 38, and the maintenance base 36 is supported by the ball screw 35 so as to be movable in the Y-axis direction.

  The ball screw 35 is engaged with the maintenance base 36 via a bearing (not shown). Further, the wiper portion 37 and the suction portion 38 are arranged in a number corresponding to each of the inkjet heads 21 arranged in the head portion 10 (in this example, a total of 24 for each color, 24, see FIG. 3). Yes.

  As shown in FIGS. 6 (a) and 6 (b), the wipe part 37 supports a wipe blade 54 for wiping the nozzle plate surface 24 and a pressure change transmitted from the pipe B34. The pressure movable portion 50 is operable in a direction facing the nozzle plate surface 24 (Z direction in the figure).

  The pressure movable unit 50 is transmitted from the sub base 53 that supports the wipe blade 54, the guide 52 that restricts the vertical movement of the sub base 53 and prevents the sub base 53 from falling off, and the pipe B34. The air spring 51 can be expanded and contracted in the Z direction by a change in pressure.

  Further, as shown in FIGS. 6A and 6B, the suction unit 38 includes a suction nozzle 55 for sucking out excess ink on the nozzle surface and thickened ink, and a pressure not shown. The pipe C56 to which the negative pressure from the supply unit is transmitted and the suction nozzle 55 are supported, and the pressure change transmitted from the pipe B34 can move up and down in the direction facing the nozzle plate surface 24 (Z direction in the figure). The pressure movable part 50 is comprised.

  The configuration of the pressure movable unit 50 of the suction unit 38 is the same as the configuration of the pressure movable unit 50 of the wipe unit 37 except that the size is slightly different. Note that the guide 52 of the pressure movable unit 50 is fixed or integrally formed with the maintenance base 36.

Next, the operation of the maintenance unit 13 during the cleaning operation will be described with reference to FIGS. 5 (a) to 5 (e) and FIGS. 6 (a) and 6 (b).
As shown in FIG. 5A, during the image recording operation of the image recording apparatus 1, the maintenance unit 13 is retracted to a position away from the print width W so as not to disturb the recording operation.

  At this position, the switch 30 is pushed by the side surface of the maintenance unit 13 (the switch is ON). This position is an origin position of a stepping motor (not shown) that is a power source for the maintenance unit 13 to move in the Y direction.

  The pipes A32 and B34 are maintained at the same pressure as the atmospheric pressure. Therefore, as shown in FIG. 6 (a), the internal pressure of the bellows-like air spring 51 of the wiper portion 37 and the suction portion 38 communicating with the pipe B34 is also the same as the atmospheric pressure. The state is in a contracted state.

In a state where the air spring 51 is contracted in the natural state, the sub-base 53 is supported by the pneumatic spring 51 at a position lower than the Z direction.
In this state, as shown by a broken line in FIG. 5B, the contact surface 40 of the wipe blade 54 and the suction nozzle 55 with the nozzle plate surface 24 is a lower position than the Z-direction position 39 of the nozzle plate surface 24. Set to This state is a state in which the wiper portion 37 and the suction portion 38 are stored in the maintenance base 36.

  When the cleaning operation is started, the power of the stepping motor is transmitted to the gear 31 and the gear 31 rotates. Thereby, the ball screw 35 attached integrally with the gear 31 rotates about the axis.

The maintenance unit 13 starts moving in the arrow B direction (minus Y direction) by the rotation of the ball screw 35.
When the number of pulses of the stepping motor reaches the set count value, the rotation of the stepping motor stops and the movement of the maintenance unit 13 also stops.

  As shown in FIG. 5 (b), the stop position is preset with the above count value so that the wiper portion 37 and the suction portion 38 are located at the end of the nozzle plate surface 24 of each inkjet head. Yes.

  Next, ink is supplied from an ink tank (not shown) to the head unit 10 by a pressurizing operation using a pump. Then, the ink is pressed out from the nozzle holes formed in the nozzle plate surface 24 of the inkjet head 21.

Next, a pressure higher than the atmospheric pressure is transmitted from the pressure supply unit via the pipe A32 and the pipe B34, the air pressure in the air spring 51 rises, and the air spring 51 extends in the plus Z direction.
Then, the sub-base 53 supported by the air spring 51 is also raised in the Z direction. Accordingly, as shown in FIGS. 5C and 5D, the position of the contact surface 40 of the wiper portion 37 and the suction portion 38 with the nozzle plate surface 24 is more than the position 39 in the Z direction of the nozzle plate surface 24. Set to a high position.

  When the positions of the wiper 37 and the suction unit 38 in the Z direction are set, the power of the stepping motor is transmitted to the gear 31 again, and the maintenance unit 13 starts to move in the arrow B direction (minus Y direction).

Accordingly, the wiper 37 and the suction unit 38 scan the nozzle plate surface 24 in the minus Y direction while contacting the nozzle plate surface 24.
At this time, the nozzle plate surface 24 in a state wetted by the discharged ink is wiped by the wiping portion 37, and excess ink is sucked by the suction portion 38. The sucked ink passes through a waste liquid path (not shown) and is collected in a waste liquid bottle.

  Ink may be transferred from the wiper 37 or the suction unit 38, but such ink is collected by the maintenance base 36 and is collected in a waste liquid bottle through a waste liquid path not shown in the same manner as described above.

  In this example, as described above, the ink is pressed out from the nozzle holes of the inkjet head 21 before wiping to wet the nozzle plate surface 24 with ink, or ink droplets are intentionally formed on the nozzle plate surface 24. ing.

  This is not only the effect of pressing out foreign matter and bubbles inside the nozzle hole, but also the effect of floating dust and paper powder adhering to the nozzle plate surface 24, and the effect on the nozzle plate surface 24 when wiping is performed. This also has the effect of washing away dust and paper dust adhering to the wipe blade 54 that scans.

  When the wiper portion 37 and the suction portion 38 are scanning the nozzle plate surface 24, as shown in FIG. 6B, thrusts F1 and F1 ′ generated by the pressure P1 inside the air spring 51, and the nozzle plate surface 24 until the positions where the reaction forces F2 and F2 ′ acting from the contact pressures P2 and P2 ′ with the wiper blade 54 and the suction nozzle 55 in contact with the fluid 24 are balanced (F1 = F2, F1 ′ = F2 ′) are obtained. The air spring 51 is contracted in the minus Z direction.

  Here, the thrusts F1 and F1 ′ that affect the contact state with the nozzle plate surface 24 are set by the supplied pressure P1 and the pressure receiving areas S1 and S1 ′ of the pressure movable unit 50. For this reason, the thrusts F1 and F1 ′ are kept constant within the vertical movement range in the Z direction set by the pressure movable unit 50.

  Therefore, the positioning of the maintenance unit 13 and the head unit 10 in the Z direction can be set within the vertical movement range of the pressure movable unit 50, and the positioning of the maintenance unit 13 in the Z direction can be easily performed.

Further, by changing the pressure P <b> 1 supplied to the pressure movable unit 50, the contact pressure of the wipe blade 54 and the suction nozzle 55 on the nozzle plate surface 24 can be easily changed.
More specifically, when an arbitrary pressure is supplied to the pressure movable unit 50, the wipe blade 54 and the suction nozzle 55 supported by the pressure movable unit 50 are applied to the nozzle plate surface 24 or a surface near the nozzle plate surface 24. Touch.

  The pressure movable unit 50 operates to a position where a thrust corresponding to the pressure supplied from a pressure supply unit (not shown) and a reaction force acting from the contact pressure are balanced, and at that position, the wipe blade 54 and the suction The nozzle 55 is held.

  FIG. 5D shows a state in which the wiper 37 and the suction unit 38 have finished scanning the nozzle plate surface 24. At this time, the wipe part 37 and the suction part 38 are stopped at positions separated from the nozzle plate surface 24.

  Accordingly, the reaction force from the nozzle plate surface 24 does not act on the wipe portion 37 and the suction portion 38. Accordingly, the pressure movable unit 50 is pushed up by the thrust from the blank spring 51, and the position of the contact surface 40 of the wiper unit 37 and the suction unit 38 with the nozzle plate surface 24 is the Z-direction position 39 of the nozzle plate surface 24. In contrast, it has returned to a higher position.

The stop position of the maintenance unit 13 is set by counting the number of pulses of the stepping motor.
Subsequently, when the pressure higher than the atmospheric pressure transmitted from the pipe A32 and the pipe B34 is lowered to the same pressure as the atmospheric pressure, the air pressure in the air spring 51 is also lowered, and the air spring 51 contracts in the minus Z direction. .

  Then, the sub-base 53 supported by the air spring 51 is also lowered in the minus Z direction, and as shown in FIG. 5 (e), the contact surface 40 of the wiper portion 37 and the suction portion 38 with the nozzle plate surface 24. The position returns to a position lower than the Z-direction position 39 of the nozzle plate surface 24.

  Accordingly, the wipe part 37 and the suction part 38 are stored in the maintenance base 36. Then, the maintenance unit 13 moves to the retracted position shown in FIG. 5A so that the recording operation can be performed, and is in a standby state until the next cleaning operation.

  Here, when the recording operation is performed immediately after the cleaning operation as described above, the maintenance unit 13 moves to the retracted position as shown in FIG. 5A, but when the recording operation is not performed, that is, When the recording operation is performed for a long time before the recording operation is performed, a cap portion is necessary to block the nozzle plate surface of the inkjet head from the outside air and prevent the ink from drying. Therefore, in the present embodiment, the maintenance unit 13 may further include a cap portion 60 as shown in FIGS.

In this case, the cap unit 60 is disposed so as not to interfere with the inkjet head 21 when the wipe unit 37 and the suction unit 38 are performing a maintenance operation.
The cap unit 60 includes a head cap 61 and a pressure movable unit 50 for sealing the nozzle plate surface 24 of the inkjet head 21. Note that the pressure movable unit 50 has the same configuration as the wipe unit 37 and the suction unit 35 described above.

  FIG. 7A shows a state in which a pressure equal to the atmospheric pressure is supplied, and shows a state in which the air spring 51 is in a natural state and contracts in the minus Z direction. FIG. 7B shows a state where the pressure P1 higher than the atmospheric pressure is supplied to the pressure movable unit 50 and the air spring 51 extends in the plus Z direction.

  In this way, the head cap 61 mounted on the pressure movable portion 50 of the cap portion 60 is applied to the edge portion of the nozzle plate surface 24 of the inkjet head 21 with a uniform and uniform force by the pressure P1 during capping. The nozzle plate surface 24 is completely sealed from the outside by contact. Even if the power of the apparatus is turned off, for example, a valve (not shown) is provided in the pipe A32 or the pipe B34 so that the head cap 61 maintains the nozzle plate surface 24 in a sealed state, and the head cap of the cap unit 60 is provided. 61 shuts off the path of the pipe A32 or the pipe B34 with the nozzle plate surface 24 completely sealed, or the head cap 61 can move the pressure with the nozzle plate surface 24 completely sealed by a lock mechanism (not shown). The operation of the unit 50 may be locked.

  The air spring 51 is configured by forming a rubber member having an elastic deformation performance in a bellows shape so that the wiper portion 37, the suction portion 38, and the cap portion 60 can be positioned by the expansion / contraction operation. Has been.

Further, the type, thickness, bellows shape, etc. of the rubber member may be arbitrarily set in consideration of the contact pressure on the nozzle plate surface due to ink resistance, processability, and expansion / contraction performance.
The rubber members include nitrile rubber (NBR), fluorine rubber (FKM), natural rubber (NR), isoprene rubber (IR), styrene butadiene rubber (SBR), butadiene rubber (BR), and chlorobrene rubber. There are various types such as (CR), butyl rubber (IIR), ethylene propylene rubber (EPDM), silicone rubber (Q), and talol sulfonated reethylene (CSM).

In this embodiment, since oil-based ink is used, the air spring 51 is made of NBR having good oil resistance and stretchability.
As described above, according to the first embodiment, the positioning operation of the wiping unit, the suction unit, and the cap unit can be set within the vertical movement range of the pressure movable unit. In addition, it is possible to provide an image recording apparatus that does not require a highly accurate moving mechanism or positioning mechanism for positioning the suction unit and the cap unit in the Z direction.

  In addition, according to the present embodiment, within the range of vertical movement of the pressure movable unit, the wipe unit, the suction unit, and the cap unit have no or small fluctuations in the pressure with which the nozzle plate surface abuts. Even if the gap between the abutment surface of the cap portion and the nozzle plate surface and the nozzle plate surface (Z direction) fluctuates, a uniform abutment pressure is applied to each nozzle plate surface. It is possible to provide an image recording apparatus capable of obtaining performance and capping performance.

  In particular, in the case of a line head in which a plurality of inkjet heads 21 are arranged, even if the heights in the Z direction of the nozzle plate surfaces of the individual inkjet heads 21 are different from each other, The part and the cap part reliably come into contact with the nozzle plate surface.

  Furthermore, since the wipe part, suction part, and cap part (wipe blade, suction nozzle, head cap) are moved using air pressure, all the contact positions in the Z direction on the nozzle plate surface are different. The wipe part and the suction part can be brought into contact with the nozzle plate surface with the same pressure.

  Further, according to the present embodiment, when the maintenance unit is in the standby state, the pressure movable portion is contracted, and the wipe portion, the suction portion, and the cap portion are stored at a position lower than the nozzle plate surface in the Z direction. It is possible to provide an image recording apparatus that can reduce the space in the Z direction of the maintenance unit.

  Further, according to the present embodiment, an image recording apparatus that can easily change the contact pressure of the wiper portion, the suction portion, and the cap portion to the nose plate by changing the pressure supplied to the pressure movable portion. It becomes possible to provide.

  In this embodiment, the pressure supplied when the pressure movable part is stored in the maintenance base is the same as the atmospheric pressure. However, by supplying a pressure lower than the atmospheric pressure from the piping part, the air spring May be shrunk. In the present embodiment, the wiper 37 or the suction unit 38 is moved in the longitudinal direction of the nozzle plate surface 24 of the inkjet head 21. However, the present invention is not limited to this, as shown in FIG. They may be arranged in a zigzag pattern and scanned in the direction of arrow C (minus X direction) in the figure. The wiper blades 54 or the suction nozzles 55 are arranged in a staggered manner in the longitudinal direction of the nozzle plate surface 24 so as to be continuous as a whole.

Accordingly, since a wide range in the longitudinal direction can be scanned at a time, the cleaning time can be performed in a short time.
FIGS. 9A and 9B are views showing a first modification of the pressure movable unit in the first embodiment described above. In FIGS. 9A and 9B, the same components or functions as those in FIGS. 6 and 7 are denoted by the same reference numerals as those in FIGS.

  As shown in FIG. 9A, in the present modification, the bellows of the air spring 51 constituting the pressure movable unit 50 is formed in the Y direction. Thus, the pressure movable unit 50 is configured to move up and down.

  FIG. 9A shows a state where the air spring 51 is supplied with the same pressure as the atmospheric pressure and the pressure movable unit 50 is contracted. FIG. 9B shows a state in which a pressure higher than the atmospheric pressure is supplied to the pressure movable unit 50 and the pressure movable unit 50 extends in the plus Z direction.

  Due to the vertical movement of the pressure operation 50, the wipe blade 54, the suction nozzle 55 or the head cap 61 has the same action as described in the first embodiment, and the positioning of the maintenance unit 13 in the Z direction is easy. Can be done.

  According to the first modification, since the bellows of the air spring is formed in a direction (Y direction) different from the operation direction (Z direction), the storage space is defined as the operation direction when the maintenance unit is in the standby state. It is possible to provide an image recording apparatus that can be set in different directions and can reduce the space in the Z direction.

  Also in the first modified example, the positioning operation of the wiper, the suction part, and the cap part can be set within the vertical movement range of the pressure movable part, so that the cleaning part can be accurately positioned with respect to the nozzle plate in the Z direction. It is possible to provide an image recording apparatus that does not require a high movement mechanism or positioning mechanism.

  Also in the first modification, good cleaning performance can be obtained even if the distance between the contact surface of the wiper portion, the suction portion, and the cap portion on the nozzle plate surface and the nozzle plate surface varies, and As in the case of the first embodiment, it is possible to easily change the contact pressure of the wiper portion, the suction portion, and the cap portion to the nose plate surface by changing the pressure supplied to the pressure movable portion. .

  Also in the first modification, the pressure supplied when the pressure movable part is stored in the maintenance base is not the same as the atmospheric pressure, but a pressure lower than the atmospheric pressure is supplied to contract the air spring. Needless to say good things.

  FIGS. 10A and 10B are views showing a second modification of the pressure movable part in the first embodiment described above. In FIGS. 10A and 10B, the same components or functions as those in FIGS. 6 and 7 are denoted by the same reference numerals as those in FIGS.

As shown in FIG. 10 (a), in this modification, the air spring constituting the pressure movable part 50 is formed of a spherical or bag-like balloon 63.
In the present modification, the pressure movable unit 50 is configured to move up and down when the balloon 63 is expanded or contracted by the pressure supplied to the balloon 63.

  FIG. 10A shows a state where the same pressure as the atmospheric pressure is supplied to the balloon 63 of the air spring, and the pressure movable unit 50 is contracted in the minus Z direction. FIG. 10B shows a state where a pressure higher than the atmospheric pressure is supplied to the pressure movable unit 50 and the pressure movable unit 50 extends in the plus Z direction.

  Also in this modification, the operation similar to that described in the first embodiment works on the wipe blade 54, the suction nozzle 55, or the head cap 61 by the vertical movement of the pressure movable unit 50, and the maintenance unit 13 The positioning in the Z direction can be easily performed.

  Also in this modification, the air spring may be contracted by supplying a pressure lower than the atmospheric pressure instead of the same pressure as the atmospheric pressure when the pressure movable part is stored in the maintenance base. Needless to say.

  FIGS. 11A, 11B, and 11C are diagrams showing a third modification of the pressure movable unit in the first embodiment described above. In FIGS. 11A, 11B, and 11C, the same components or functions as those in FIGS. 6 and 7 are given the same reference numerals as those in FIGS.

  The pressure movable unit 50 includes a sub base 53 that supports the wipe blade 54, the suction nozzle 55, or the head cap 61, a guide 52 that regulates the vertical movement of the sub base 53 and prevents the sub base 53 from falling off. A cover 62 fixed so as to seal the sub-base 53 to the maintenance base 36 in a state where the entire circumference of the bottom opening of the sub-base 53 is closed and the sub-base 53 is bent so as to be movable up and down. It is composed of

  FIG. 11B shows a state where a pressure higher than the atmospheric pressure is supplied to the pressure movable unit 50 and the pressure movable unit 50 extends in the plus Z direction. FIG. 11C shows a state in which a pressure lower than atmospheric pressure is supplied to the pressure movable unit 50 and the pressure movable unit 50 is contracted in the minus Z direction.

  By the vertical movement of the pressure movable unit 50, the wipe blade 54, the suction nozzle 55, or the head cap 61 has the same action as described in the first embodiment, and the positioning of the maintenance unit 13 in the Z direction is facilitated. Can be done.

  In the case of this modification as well, the pressure supplied when the pressure movable unit 50 is stored in the maintenance base 36 does not necessarily need to be lower than the atmospheric pressure. In short, since the cover 62 only has to be bent downward, a pressure of the same pressure as the atmospheric pressure may be supplied.

  FIG. 12 is a diagram illustrating a fourth modification of the pressure movable unit in the first embodiment described above. In FIG. 12, the same components or functions as those in FIGS. 6 and 7 are given the same numbers as in FIGS.

  As shown in FIG. 12, in this modification, the pressure movable unit 50 on which the wiper unit 37, the suction unit 38, or the cap unit 60 (the wipe blade 54, the suction nozzle 55, or the head cap 61) is mounted is a lower base. 65, an upper support base 66, and the periphery of the base 65 and the bellows 64 connecting the periphery of the support base 66.

That is, in the present modification, a plurality of wipe parts 37 or suction parts 38 or cap parts 60 are arranged on the pressure movable part 50.
When the pressure in the space where the base 65 and the support 66 are connected to each other by the bellows 64, that is, the internal pressure of the air spring is the same as the atmospheric pressure, the pressure movable unit 50 contracts in the plus Z direction. The evacuation state is maintained. During the cleaning operation, a pressure P1 higher than the atmospheric pressure is supplied through the pipe B34.

  Accordingly, when the support base 66 is raised from the lower retreat position to the upper maintenance position, the plurality of wipe portions 37, the suction portions 38, or the cap portions 60 are collectively raised and come into contact with the nozzle plate surface.

According to this modification, by sharing the pressure movable unit 50, it is possible to simultaneously raise or lower the plurality of wipe units 37, the suction unit 38, or the cap unit 60.
In addition, the same operations and effects as described in the first embodiment can be obtained.

  FIGS. 13A and 13B are views showing a fifth modification of the pressure movable portion as the first embodiment. In FIG. 13, the same components or functions as those in FIGS. 6 and 7 are given the same numbers as in FIGS.

  As shown in FIG. 13 (a), in this modification, the pressure receiving areas S1, S2, and S3 that receive the pressure P supplied through the pipe B34 are formed differently in each pressure movable portion 50. Has been.

  At the time of the cleaning operation, as shown in FIG. 13B, thrusts F1, F3, and F5 corresponding to the sizes of the supply pressure P and the pressure receiving areas S1, S2, and S3 act on the pressure movable parts. Then, the pressure movable portion expands and contracts to a position (F1 = F2, F3 = F4, F5 = F6) where reaction forces F2, F4, and F6 acting from the contact pressure with the nozzle plate surface are balanced.

  According to this modification, even if a common pipe part (pipe B34) is used, the contact pressures on the nozzle plate surface of a plurality of wipe parts or suction parts or cap parts set to different pressures. It is possible to provide an image recording apparatus that can perform the above operation.

In addition, the same operations and effects as described in the first embodiment can be obtained.
FIG. 14 is a diagram illustrating a sixth modification of the pressure movable unit as the first embodiment. In FIG. 14, the same components or functions as those in FIGS. 6 and 7 are given the same numbers as in FIGS. 6 and 7.

  As shown in FIG. 14, in this modification, the pipe B34 for supplying pressure to the pressure movable unit 50 is configured by two paths of a pipe 34-1 and a pipe 34-2 as separate paths, and the pipe 34- 1 and the pipe 34-2 are respectively connected to pressure movable parts on which different types of maintenance units are mounted.

Another type of maintenance unit is, for example, a wiper 37 and a suction part 38. Different pressures Q and P can be supplied to the pipe 34-1 and the pipe 34-2, respectively.
In accordance with the pressures (Q and P) supplied to the pipe 34-1 and the pipe 34-2, the pressure movable part 50 expands and contracts, and the position setting in the Z direction of the wipe part 37 and the suction part 38 is independent. Done.

  As described above, according to this modification, the pressure movable unit 50 can be made to perform an independent operation for each pipe, so that the wiper unit 37 and the suction unit 38 are in contact with the nozzle plate surface. It is possible to provide an image recording apparatus in which execution can be arbitrarily set according to piping.

In addition, the same operations and effects as described in the first embodiment can be obtained.
By the way, in 1st Embodiment mentioned above and its 1st-6th modification, as shown to Fig.5 (a)-(e), the piping A32 of the maintenance unit 13 has a stretching property. Although a coiled tube is used, the configuration of the piping portion is not limited to this. In short, any configuration that can transmit pressure to the pressure movable portion may be used.

  FIGS. 15A and 15B are diagrams showing another configuration example in which the piping portion has elasticity. As shown in FIGS. 15 (a) and 15 (b), a thin tube 57 slidably supported in a pipe B34 formed in the maintenance base 36 is arranged so that the pipe B34 can be expanded and contracted. As piping, it can also be set as the structure which transmits a pressure to a pressure movable part.

In the first embodiment described above and the first to sixth modifications thereof, the operation direction at the time of maintenance of the wiper portion 37 or the suction portion 38 or the cap portion 60 with respect to the nozzle plate surface 24 of the inkjet head 21 is determined as follows. Although the minus Y direction is used, the present invention is not limited to this. For example, the operation may be performed in either the plus or minus direction in the X direction. (Second Embodiment)
FIGS. 16A and 16B are diagrams showing the configuration and operation of the pressure movable unit of the image recording apparatus according to the second embodiment. The configuration of the image recording apparatus in this example is substantially the same as the configuration of the image recording apparatus shown in FIGS. 1 to 3 except for the configuration of the pressure movable portion.

Since the basic configuration of the pressure movable part of the present invention has been described with reference to FIGS. 6 and 7, FIGS. 16 (a) and 16 (b) show the configuration of the pressure movable part 50 in a simplified manner.
In the present embodiment, when the internal pressure of the air spring of the pressure movable unit 50 is the same as the atmospheric pressure, the pressure movable unit 50 has a state of extending in the plus Z direction as shown in FIG. Is maintained.

When a pressure lower than the atmospheric pressure is supplied into the air spring, the air spring is configured to contract in the minus Z direction as shown in FIG.
Thereby, in the standby state (the state in the retracted position, the same applies hereinafter), the wipe portion 37 or the suction portion 38 or the cap portion 60 (the wipe blade 54 or the suction nozzle 55 or the head cap 61) supported by the pressure movable portion 50. ) And the nozzle plate surface is at a position H1 higher than the nozzle plate surface.

  When starting the cleaning operation, as shown in FIG. 16B, the internal pressure of the air spring is set to −P (negative pressure), which is a pressure lower than the atmospheric pressure. As a result, the air spring contracts, and the contact surface between the wiper portion 37 or the suction portion 38 or the cap portion 60 and the nozzle plate surface is at a position lower than the nozzle plate surface (a position lower by ΔH than H1 in the figure). .

  FIGS. 17A and 17B are diagrams for explaining the operation of maintenance of the pressure movable portion of the image recording apparatus in the second embodiment. In FIGS. 4A and 4B, the configuration of the pressure movable unit 50 is illustrated more simply than FIG. 16 by omitting the piping B34.

  In this second embodiment, while maintaining the state shown in FIG. 16 (b), the maintenance base (not shown) that supports the wiper portion 37, the suction portion 38, or the cap portion 60 is provided at the end of the nozzle plate surface. Move to the department. As a result, as shown in FIG. 17A, the maintenance base 36 (not shown) that supports the wiper portion 37, the suction portion 38, or the cap portion 60 faces the nozzle plate surface.

  Next, the internal pressure of the air spring is returned to atmospheric pressure, and the contact surface between the wipe blade 54 or the suction nozzle 55 or the head cap 61 and the nozzle plate surface is returned to a position H1 higher than the nozzle plate surface.

  Since the air spring has a repulsive force against an elastic deformation in a natural state where the internal pressure is the same as the atmospheric pressure, the wipe blade 54, the suction nozzle 55, or the head cap 61 is as shown in FIG. Well abuts the nozzle plate surface.

  In FIG. 17B, for example, the third inkjet head 21 (21-3) is slightly displaced relative to the inkjet heads 21 (21-1, 21-4) at both ends. The state is shown in which the second inkjet head 21 (21-2) is further displaced.

  Thus, even if the position of the nozzle plate surface of the inkjet head 21 is not aligned vertically, if the range of the positional shift is within the range of ΔH in FIG. 16B, the air spring is moved upward in the natural state. The wipe part 37 or the suction part 38 or the cap part 60 is in good contact with the nozzle plate surface by the elastic force.

  Here, a pressure higher than the atmospheric pressure is further supplied to the air spring to increase the internal pressure of the air spring higher than the atmospheric pressure. In this state, the nozzle plate surface is scanned to generate a thrust according to the pressure in the air spring, and the wiper blade 54 or the suction nozzle 55 contacts the nozzle plate surface to clean the nozzle plate surface. Can do. Alternatively, the nozzle plate surface 24 is sealed with the head cap 61.

  When the scanning or capping of the nozzle plate surface is completed, the wipe blade 54 or the suction nozzle 55 or the head cap 61 is returned to the standby position by an operation opposite to the operation performed previously.

  According to the second embodiment, when the cleaning operation is started, the internal pressure of the pressure movable unit 50 is lowered so that the contact surface between the wiper unit 37 or the suction unit 38 or the cap unit 60 and the nozzle plate surface is provided. Since it is lowered to a position lower than the nozzle plate surface, the relative vertical movement of the maintenance unit 13 and the head unit 10 can be suppressed to a small level, and the mechanism for the vertical movement can be simplified.

  Also in this case, as in the case of the first embodiment, the positioning operation of the wiping part, the suction part, and the cap part can be set within the range of the vertical movement of the pressure movable part. Therefore, it is possible to provide an image recording apparatus that does not require a highly accurate moving mechanism or positioning mechanism for positioning the wiper portion and the suction portion in the Z direction.

In this embodiment, when the wipe blade 54 or the suction nozzle 55 or the head cap 61 is brought into contact with the nozzle plate surface, the pressure supplied to the air spring is set to a pressure higher than the atmospheric pressure. As shown in FIG. 5, the air spring has a natural state in which the internal pressure of the air spring is the same as the atmospheric pressure, and the air spring has a contact surface with the nozzle plate surface of the wipe blade 54 or the suction nozzle 55 or the head cap 61 from the nozzle plate surface. Since the elastic thrust is maintained at the high position H1, maintenance may be performed simply by returning the internal pressure of the air spring to the same pressure as the atmospheric pressure.
(Third embodiment)
FIGS. 18A and 18B are diagrams showing the configuration and operation of the main part of the maintenance unit of the image recording apparatus according to the third embodiment.

FIGS. 19 (a) and 19 (b) are diagrams for explaining the operation of the maintenance unit in the third embodiment following FIGS. 18 (a) and 18 (b).
The configuration of the image recording apparatus in this example is substantially the same as the configuration of the image recording apparatus shown in FIGS. 1 to 3 except for the configuration of the pressure movable portion of the maintenance unit.

  18 (a), (b) and FIGS. 19 (a), (b), the same components or functions as those in FIGS. 6 and 7 are given the same numbers as in FIGS. It shows. 18 (a), 18 (b) and 19 (a), 19 (b), the maintenance unit 13 is moved from the downstream side in the recording medium conveyance direction of FIG. The figure seen in the direction of arrow A) is shown.

  In the third embodiment, as shown in FIGS. 18A and 18B, a wiper portion 37 and a cap portion 60 are supported on the maintenance base. As shown in FIG. 18 (a), the wipe part 37 supports the wipe blade 54 for wiping the nozzle plate surface, and faces the nozzle plate surface by the pressure change transmitted from the pipe B34. It is comprised by the pressure movable part 50 which can be moved up and down by the direction (Z direction of a figure).

  Further, the pressure movable unit 50 regulates the vertical movement of the sub base 53 supporting the wipe blade 54 and prevents the sub base 53 from dropping from the maintenance base 36. And an air spring 51 that can be expanded and contracted in the Z direction by a change in pressure transmitted from the pipe B34. The guide 52 is fixed or integrally formed with the maintenance base 36.

  The cap portion 60 is capped so as to shield the nozzle plate surface from the outside air, reduces the increase in ink viscosity due to drying, and supports the head cap 61. By the pressure change transmitted from the pipe B34, It is composed of a pressure movable portion 70 that can move up and down in a direction (Z direction in the figure) facing the nozzle plate surface.

  The pressure movable unit 70 includes a sub base 53 that supports the head cap 61, a guide 52 that restricts the vertical movement of the sub base 53, and prevents the sub base 53 from falling off the maintenance base 36. A spring 73 that urges the sub-base 53 in the Z direction, and an air spring 51 that is supported by the maintenance base 53 and can be expanded and contracted in the Z direction by the pressure change transmitted from the pipe B34, and the operation of the air spring 51 A support plate 71 that is transmitted to the sub-base 53 and a shaft 72 fixed to the support plate 71 are configured.

The shaft 72 has an upper end fixed to the sub-base 53, passes through a through hole formed in the maintenance base 36, and a lower end is fixed to the support plate 71.
The guide 52 is fixed to or integrally formed with the maintenance base 36. Moreover, the piping B34 and the piping B34-2 are each connected individually so that the pressure supplied to the wipe part 37 and the cap part 60 can be performed independently.

Next, the operations of the wipe unit and the cap unit in the cleaning operation will be described with reference to FIGS. 18 (a) and 18 (b) and FIGS. 19 (a) and 19 (b).
FIG. 18A shows the state of the wipe unit and the cap unit when the maintenance unit is retracted from the recording medium conveyance path when the image recording apparatus 1 is performing the recording operation.

  At this time, the same pressure as the atmospheric pressure is supplied from the piping B34 (34-1 and 34-2) formed in the maintenance base 36, and the air springs of the wipe part 37 and the cap part 60 are supplied. Each 51 is in a contracted state.

  When the air spring 51 is contracted, the contact surface of the wipe portion 37 that contacts the nozzle plate surface is set to a lower position in the Z direction than the nozzle plate surface, and the contact surface of the cap portion is set to a higher position. Has been.

When the cleaning operation is started, a pressure higher than the atmospheric pressure is transmitted to the pipe 34-2, the air pressure in the air spring 51 of the cap portion rises, and the air spring 51 extends in the minus Z direction.
Thereby, the support plate 71 supported by the air spring 51 is pushed downward (minus Z direction), and the shaft 72 fixed to the support plate 71 slides downward. As the shaft 72 slides downward, the sub-base 53 fixed to the shaft 72 descends downward.

Accordingly, as shown in FIG. 18B, the position of the contact surface of the cap portion 60 with the nozzle plate surface is maintained at a lower position than the nozzle plate surface.
At this time, the pressure P supplied to the cap unit 60 is set so that the thrust in the minus Z direction by the air spring 51 is greater than the plus Z direction force to which the biasing force of the spring 73 acts.

  Next, the maintenance unit 13 moves until the wipe portion is positioned at the end portion of the nozzle plate surface of the inkjet head in a state where the contact surface of the cap portion 60 is maintained at a lower position than the nozzle plate surface.

  Then, a pressure higher than the atmospheric pressure is supplied to the pipe 34-1, the air spring 51 of the wipe part extends upward, and the wipe part also rises. The maintenance unit 13 moves again at the position where the wipe portion is raised, and the wiping operation of the nozzle plate surface is performed as shown in FIG.

In addition, since the cap part 60 is located below the nozzle plate surface, it does not interfere with the inkjet head 21 even while the wiping part 37 is performing the wiping operation.
When the wiping operation of the wipe part 37 is completed, the same pressure as the atmospheric pressure is supplied to the pipe 34-1 again, and the wipe part 37 descends below the nozzle plate surface.

  The maintenance unit 13 returns to the standby position shown in FIG. 18A, the pressure supplied to the cap unit 60 is also returned to the same pressure as the atmospheric pressure, and the image recording apparatus returns to a state where the recording operation can be performed.

When the recording operation is not performed for a long time, the capping operation of the nozzle plate surface 24 is performed when an arbitrary time set in the image recording apparatus 1 has elapsed.
The operations of the wiping unit 37 and the cap unit 60 in the capping operation will be described with reference to FIGS. 18A and 18B and FIGS. 19A and 19B again.

  FIG. 18A shows the state of the wiper 37 and the cap 60 at the standby position as described above. The contact surface of the wipe portion that contacts the nozzle plate surface is set to a position lower in the Z direction than the nozzle plate surface, and the contact surface of the cap portion is set to a high position.

  When the cleaning operation is started, a pressure higher than the atmospheric pressure is transmitted to the pipe 34-2 as described above, and the position of the contact surface with the nozzle plate surface of the cap portion 60 as shown in FIG. Is maintained at a low position with respect to the nozzle plate surface.

  Next, the maintenance unit 13 moves to a position where the nozzle plate surface of the inkjet head and the cap unit 60 face each other. And the pressure of the same pressure as atmospheric pressure is supplied to the piping 34-2, and the cap part 60 rises in the plus Z direction.

  When the cap portion 60 is lifted, as shown in FIG. 19B, the head cap 61 comes into contact with the nozzle plate surface 24, so that the nozzle plate surface is blocked from outside air and the capping operation is completed.

  When the recording operation is instructed from the capped state to the image recording apparatus 1 by an input signal from a conversion panel or a personal computer connected to the network, the image recording apparatus 1 is put on standby by a movement opposite to the capping operation. Return to position.

In addition, since the wipe part 37 is located below the nozzle plate surface, it does not interfere with the inkjet head 21 even if the capping operation is performed.
As described above, according to the third embodiment described above, the positioning operation of the wiper and the cap can be set within the range of the vertical movement of the pressure movable unit, so that the wiper and the cap with respect to the nozzle plate surface can be set. It is possible to provide an image recording apparatus that does not require a highly accurate moving mechanism or positioning mechanism for positioning in the Z direction.

  In addition, according to the present embodiment, within the range of vertical movement of the pressure movable portion, the pressure at which the wipe portion and the cap portion abut on the nozzle plate surface has no or small fluctuations, so that the wipe portion and the cap portion move toward the nozzle plate surface. It is possible to provide an image recording apparatus capable of obtaining good cleaning performance even if the distance between the contact surface of the nozzle plate and the nozzle plate surface varies.

  Further, according to the present embodiment, when the maintenance unit is in the standby state, the pressure movable part can be contracted by the supplied pressure, so that the wipe part and the cap part are located in the Z direction from the nozzle plate surface. It is possible to provide an image recording apparatus that can be stored at a low position and can reduce the space in the Z direction of the maintenance unit.

  In addition, according to the present embodiment, an image recording apparatus that can easily change the contact pressure on the nozzle plate surface of the wipe portion and the cap portion by changing the pressure supplied to the pressure movable portion is provided. Is possible.

  Further, according to the present embodiment, the pressure supplied to the wipe unit and the cap unit can be capped to the nozzle plate surface at the same pressure as the atmospheric pressure, so that the image recording apparatus can be turned off for a long time. It is possible to provide an image recording apparatus in which the capping performance does not deteriorate even in an environment where it is left unattended.

  In the present embodiment, when the head cap is brought into contact with the nozzle plate surface, the pressure supplied to the pressure movable portion is the same as the atmospheric pressure, but in order to adjust the force of the cap portion coming into contact with the nozzle plate surface. In addition, a pressure lower than or higher than atmospheric pressure may be supplied.

  For example, when the air spring 51 is fixed to both the maintenance base 36 and the support plate 71, when a pressure lower than the atmospheric pressure is supplied to the air spring, the air spring contracts and the cap portion 60 extends in the Z direction. The force in the upward direction increases, and the contact pressure of the head cap 61 urged by the spring 73 on the nozzle plate surface increases.

  Conversely, when a pressure higher than the atmospheric pressure is supplied, the force that biases the head cap 61 with the spring 73 decreases due to the force with which the air spring extends downward, so that the head cap 61 is applied to the nozzle plate surface. The contact force can be reduced.

In this embodiment, the cleaning operation and the capping operation are performed independently, but the capping operation may be performed in the middle of the cleaning operation.
Specifically, during the cleaning operation, immediately after the wipe unit 37 scans the nozzle plate surface, the maintenance unit 13 is slightly moved to a position where the cap unit 60 faces the nozzle plate surface 24. Then, the capping operation can be continuously performed by supplying the pipe 34-2 with the same pressure as the atmospheric pressure.

In the present embodiment, the suction function is not provided, but a suction pipe is provided in the cap portion, and ink is supplied from the nozzle holes formed in the nozzle plate surface by applying a pressure lower than the atmospheric pressure during capping. A suction function may be provided so as to perform suction.
(Fourth embodiment)
FIGS. 20A and 20B are diagrams illustrating the configuration of a pressure supply unit that supplies pressure to the wipe unit and the suction unit that are disposed in the maintenance unit of the image recording apparatus according to the fourth embodiment.

In this example, in the configuration shown in FIGS. 20 (a) and 20 (b), the same components or functional parts as those in FIGS. 6 (a) and 6 (b) have the same numbers as those in FIGS. 6 (a) and 6 (b). Is given.
Further, the image recording apparatus in this example is almost the same as the configuration of the image recording apparatus shown in FIGS. Further, since the configuration of the pressure movable portion has been described with reference to FIG. 6, only the portions of the configuration of the pressure movable portion 50 that need to be described are given numbers in FIGS. 20 (a) and 20 (b).

  As shown in FIG. 20 (a), the pressure supply unit 75 sucks air from the IN-side port and discharges the sucked air to the OUT-side port, and checks the flow of fluid in only one direction. The valve A86 and the check valve B88, a positive pressure tank 85 that stores an arbitrary amount of pressure higher than the atmospheric pressure, a negative pressure tank 89 that stores an arbitrary amount of pressure lower than the atmospheric pressure, and whether to flow or stop the piping path are switched. It comprises a switching valve A82, a switching valve B83, a switching valve C84, a flow rate control valve A92 that changes the flow rate of the piping path, and a flow rate control valve B93.

The positive pressure tank 85 and the negative pressure tank 89 are incorporated with a pressure control valve A90 and a pressure control valve B91 for maintaining the inside of the tank at a desired pressure.
Next, how the pipes are connected will be described.

The IN side port of the pump 87 is connected to the check valve 88. The check valve 88 is connected to the negative pressure tank 89. The negative pressure tank 89 is connected to the switching valve C84.
The switching valve C84 is connected to the flow control valve B93. The flow rate control valve B93 is connected to a pipe D80 formed in the maintenance base 36 via a pipe E81. The pipe D80 is connected to the suction nozzle 55 via the pipe C56.

The OUT side port of the pump 87 is connected to the check valve A86. The check valve A86 is connected to the positive pressure tank 85.
The positive pressure tank 85 is connected to the switching valve B83. The switching valve B83 is connected to a switching valve A82 and a flow rate control valve A92 that are open to the atmosphere on one side. The flow control valve A92 is connected to a pipe B34 formed in the maintenance base 36 via a pipe A32.

The pipe B34 is connected to each pressure movable portion 50 that allows the wiper portion 37 and the suction portion 38 to move up and down in the Z direction.
Next, the operation of the pressure supply unit 75 during the nozzle plate surface cleaning operation will be described.

FIG. 20A shows the state of the pressure supply unit 75 when the maintenance unit 13 is retracted from the recording medium conveyance path when the image recording apparatus is performing the recording operation.
The pump 87 is stopped, and the internal pressures of the positive pressure tank 85 and the negative pressure tank 89 have not reached a desired pressure.

The switching valve B83 and the switching valve C84 are set at closed positions where the flow in the path is stopped, and the switching valve A82 is set at a position where the path is opened to the atmosphere.
Therefore, the suction nozzle 55 connected from the switching valve C84 via the flow rate control valve B93, the pipe E81, the pipe D80, and the pipe C56 does not perform the suction operation.

  Further, the two pressure movable parts 50 connected from the switching valve A82 via the flow rate control valve A92, the pipe A32, and the pipe B34 are supplied with the same pressure as the atmospheric pressure, and the wipe part 37 is supplied. The suction portion 38 is set at a position lower than the nozzle plate surface in the Z direction.

When the cleaning operation is started, the maintenance unit 13 starts to move toward the nozzle plate surface end of the inkjet head.
At this time, the pump 87 starts moving, sucks air from the IN side port, and starts an operation of discharging the sucked air to the OUT side port.

Here, the check valve 88 connected to the IN side port is a one-way valve that allows air to flow only from the negative pressure tank 89 toward the IN side port of the pump 87.
Therefore, when the switching valve C84 is closed, a pressure lower than the atmospheric pressure is accumulated in the negative pressure tank 89 by the capacity of the negative pressure tank 89.

The pressure in the negative pressure tank 89 is maintained at a desired pressure by the pressure control valve B91 incorporated in the negative pressure tank 89.
Similarly, the check valve 86 connected to the OUT side port is a one-way valve that allows air to flow only from the OUT side port of the pump 87 toward the positive pressure tank 85.

Therefore, when the switching valve B 83 is closed, a pressure higher than the atmospheric pressure is accumulated in the positive pressure tank 85 by the capacity of the positive pressure tank 85.
The pressure in the positive pressure tank 85 is maintained at a desired pressure by the pressure control valve A90 incorporated in the positive pressure tank 85.

  When the maintenance unit 13 is positioned at the end of the nozzle plate surface of the inkjet head, as shown in FIG. 20B, the switching valve 82 is closed from the atmosphere by an electrical signal from an electrical unit (not shown). Switch to the state.

  In addition, the switching valve B83 and the switching valve C84 are also switched so that the pressure accumulated in the positive pressure tank 85 and the negative pressure tank 89 is applied to each pipe connected to the positive pressure tank 85 and the negative pressure tank 89. Supplied.

  Since the two pressure movable parts 50 are connected to the tip of the pipe A32 to which a pressure higher than the atmospheric pressure is supplied, a pressure higher than the atmospheric pressure is supplied to the pressure movable part 50, and the wiper 37 and the suction The portion 38 is set at a position higher than the nozzle plate surface in the Z direction.

  Further, since the suction nozzle 55 is connected to the end of the pipe E81 to which a pressure lower than the atmospheric pressure is supplied, a pressure lower than the atmospheric pressure is supplied to the suction nozzle 55, and the suction unit 38 performs the suction operation. To start.

In this state, the maintenance unit 13 scans the nozzle plate surface, whereby the wiping operation and the suction operation of the nozzle plate surface are performed.
When the suction operation is performed, the ink remaining on the nozzle plate surface is sucked, so that the ink flows from the suction nozzle 55 through the pipe C56 and flows down. Therefore, it does not flow into the check valve 88.

The ink accumulated in the negative pressure tank is discarded when a certain amount of ink is accumulated by a detection function (not shown) and a notification function to the user.
Further, since the flow rate supplied to the wiper unit 37 and the suction unit 38 can be changed by the throttle amount of the flow rate control valve 92 and the flow rate control valve 93, the speed at which the wiper unit 37 and the suction unit 38 are moved up and down, and the suction unit 38 The suction pressure can be set arbitrarily.

  When the scanning of the nozzle plate surface is completed, the pressure movable unit 50 contracts and returns to the state shown in FIG. That is, the switching valve A82 is switched to the atmosphere open state, and the switching valve B83 and the switching valve C84 are switched to the closed state.

Further, the operation of the pump 87 is also stopped. Then, the maintenance unit 13 returns from the paper conveyance path to the position where it is retracted, and the cleaning operation is completed.
As described above, according to the present embodiment, since the pressure generation unit that generates the pressure to be supplied to the pressure movable unit and the suction unit is shared, the number of pressure generation units can be reduced.

  In addition, according to the present embodiment, since the flow rate supplied to the wiper unit 37 and the suction unit 38 can be changed by the throttle amount of the flow rate control valve, the speed at which the wiper unit 37 and the suction unit 38 move up and down, and the suction unit The suction pressure of 38 can also be set arbitrarily.

In the present embodiment, the ink sucked by the suction unit is configured to accumulate in the negative pressure tank. However, a waste liquid collection bottle for collecting ink may be disposed in the path.
Further, in the present embodiment, when the pressure movable unit 50 is contracted, the pressure to be supplied is the same as the atmospheric pressure, but it may be contracted by supplying a pressure lower than the atmospheric pressure.

  In the present embodiment, the pressure supply unit includes a positive pressure tank and a negative pressure tank, but the flow rate supplied to the pressure movable unit and the suction unit can be sufficiently allowed by the driving capability of the pump. In this case, the positive pressure tank and the negative pressure tank can be removed from the configuration.

  In the present embodiment, the pressure supply unit is provided with a plurality of flow rate control valves that change the flow rate of the piping path, but when the operation speed of the pressure movable unit or adjustment of the suction capacity is not required, Can be removed from the configuration.

In addition, this invention is not limited to the said embodiment, In the implementation stage, it can change variously in the range which does not change the summary.
In the present invention, the line head type image recording apparatus has been described. However, the present invention is not limited to this, and the present invention can also be applied to a serial type image recording apparatus that performs image recording by scanning an inkjet head in the main scanning direction of a recording medium. .

(a) is a side view of the image recording apparatus in the first embodiment of the present invention, and (b) is a top view thereof. (a), (b) is a figure which shows the movement operation | movement of each part concerned when the maintenance unit of the image recording device in 1st Embodiment performs cleaning operation | movement. 3 is a top view of a head unit of the image recording apparatus according to the first embodiment. FIG. (a), (b) is a figure which shows the other example of the evacuation direction of a maintenance unit. (a)-(e) is a figure which shows the head part and maintenance unit which looked at the image recording device in 1st Embodiment from the recording-medium conveyance direction downstream. (a), (b) is a figure explaining the structure and operation | movement of the wipe part of the maintenance unit of the image recording device in 1st Embodiment, and a suction part. (a), (b) is a figure which shows the example which applied the pressure movable part to the cap part in the image recording device in 1st Embodiment. It is a figure which shows the example which made the operation | movement direction at the time of the maintenance of the wipe part or suction part with respect to a nozzle plate surface the minus X direction. (a), (b) is a figure which shows the 1st modification of the pressure movable part of the image recording apparatus in 1st Embodiment. (a), (b) is a figure which shows the 2nd modification of the pressure movable part of the image recording apparatus in 1st Embodiment. (a), (b), (c) is a figure which shows the 3rd modification of the pressure movable part of the image recording apparatus in 1st Embodiment. It is a figure which shows the 4th modification of the pressure movable part of the image recording device in 1st Embodiment. (a), (b) is a figure explaining the structure and operation | movement of the 5th modification of the image recording device in 1st Embodiment. It is a figure which shows the 6th modification of the pressure movable part as 1st Embodiment. (a), (b) is a figure which shows the other structural example which gives elasticity to the piping part of the maintenance unit of the image recording device in 1st Embodiment. (a), (b) is a figure which shows simply the structure and operation | movement of a pressure movable part of the image recording apparatus in 2nd Embodiment. (a), (b) is a figure explaining the operation | movement at the time of the maintenance of the pressure movable part of the image recording device in 2nd Embodiment. (a), (b) is a figure which shows the structure and operation | movement of the principal part of the maintenance unit of the image recording apparatus in 3rd Embodiment. (a), (b) is a figure for demonstrating operation | movement of the maintenance unit in 3rd Embodiment following FIG. 18 (a), (b). (a), (b) is a figure which shows the structure of the pressure supply part which supplies a pressure to the wipe part and suction part which are arrange | positioned at the maintenance unit of the image recording apparatus in 4th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image recording device 10 Head part 11 Ink bottle 12 Base 13 Maintenance unit 14 Recording medium collection | recovery unit 15 Recording medium 16 Recording medium conveyance unit 17 Recording medium supply unit 18 Carriage 19 Belt 21 (21-1, 21-2, 21 -3, 21-4) Inkjet head 22 Line head 23 Groove 24 Nozzle plate surface 37 Wipe part 38 Suction part 32 Pipe A
34 Piping B
35 Ball screw 36 Maintenance base 37 Wipe part 38 Suction part 39 Position of nozzle plate surface in Z direction 40 Contact surface of wipe blade and suction nozzle with nozzle plate surface 50 Pressure movable part 51 Air spring 52 Guide 53 Sub base 54 Wipe blade 55 Suction nozzle 56 Piping C
57 Narrow tube 60 Cap part 61 Head cap 62 Cover 63 Balloon 64 Bellows 65 Base 66 Support base 70 Pressure movable part 71 Support plate 72 Shaft 73 Spring 75 Pressure supply part 80 Pipe D
81 Piping E
82 Switching valve A
83 Switching valve B
84 Switching valve C
85 Positive pressure tank 86 Check valve A
87 Pump 88 Check valve B
89 Negative pressure tank 90 Pressure control valve A
91 Pressure control valve B
92 Flow control valve A
93 Flow control valve B

Claims (16)

An inkjet head having a nozzle plate in which nozzle holes for discharging ink toward a recording medium are formed;
A maintenance unit for performing maintenance of the nozzle plate;
A pressure supply unit for supplying an arbitrary air pressure to the maintenance unit;
Comprising
The maintenance unit has a pressure movable part, and the pressure movable part moves the maintenance unit to a maintenance position where maintenance of the nozzle plate is performed by the air pressure supplied from the pressure supply part.
An image recording apparatus.   The maintenance unit caps a wipe blade part having a wipe blade for wiping the surface of the nozzle plate of the inkjet head or a suction part having a suction nozzle for sucking ink on the surface of the nozzle plate or a surface of the nozzle plate. The image recording apparatus according to claim 1, further comprising at least one of cap portions having a head cap. A line head is configured by arranging one or a plurality of the inkjet heads so as to be not less than the width of the recording medium for each color of the ink,
The image recording apparatus according to claim 2, further comprising at least one set of the number of wipe units, suction units, or cap units equal to the number of inkjet heads of the line head.   The image recording apparatus according to claim 3, wherein at least one of the wiping portion or the suction portion is arranged in a staggered manner with respect to a longitudinal direction of the nozzle plate.   The image recording apparatus according to claim 2, wherein a plurality of at least one of the wipe blade, the suction nozzle, and the head cap are arranged on the pressure movable unit.   The maintenance unit moves to a maintenance position when the air pressure supplied to the pressure movable part is higher than the atmospheric pressure, and the air pressure supplied to the pressure movable part is the same as or lower than the atmospheric pressure. The image recording apparatus according to claim 1, wherein the image recording apparatus is separated from the maintenance position when the pressure is applied.   The maintenance unit moves to a maintenance position when the air pressure supplied to the pressure movable part is equal to or higher than the atmospheric pressure, and the air pressure supplied to the pressure movable part is lower than the atmospheric pressure. The image recording apparatus according to claim 1, wherein the image recording apparatus is separated from the maintenance position at a certain time.   The maintenance unit moves to a maintenance position when the air pressure supplied to the pressure movable part is equal to or lower than the atmospheric pressure, and the air pressure supplied to the pressure movable part is less than the atmospheric pressure. The image recording apparatus according to claim 1, wherein when the pressure is high, the image recording apparatus is separated from the maintenance position.   A plurality of pressure receiving areas formed in the pressure movable portion that sets the thrust acting on the wipe portion, the suction portion, and the cap portion in accordance with the supplied pressure are arranged in different sizes. The image recording apparatus according to claim 2.   A plurality of pressure supply units that generate different pressures, and a plurality of piping units that can independently transmit a plurality of different pressures generated by the pressure supply unit, and connected to the piping unit 3. The image recording apparatus according to claim 1, wherein the maintenance position of the pressure movable unit and the position of separation from the maintenance position are set independently for each of the piping units.   The pressure movable unit includes a sub-base that supports the wipe blade, the suction nozzle, or the head cap, a guide that regulates the operation of the sub-base and prevents the drop-off, and a pressure supplied from the pressure supply unit. The image recording apparatus according to claim 1, further comprising an air spring that can be expanded and contracted.   The image recording apparatus according to claim 11, wherein the air spring has a bellows, and the bellows is arranged in a direction substantially perpendicular to an operation direction of the pressure movable unit.   The pressure movable unit includes a sub-base that supports the wipe blade, the suction nozzle, or the head cap, a guide that regulates the operation of the sub-base and prevents the drop-off, and a bottom opening of the sub-base. The cover is fixed so as to be sealed to the maintenance base unit in a bent state so as to close the periphery and allow the sub-base to move up and down. Image recording device.   The image recording apparatus according to claim 1, wherein the generation of the pressure supplied to the pressure movable unit and the pressure supplied to the suction unit is shared by a pump disposed in the pressure supply unit. .   The pressure supply unit includes a pump that generates an arbitrary pressure, a check valve that is disposed at both ends of the input / output side of the pump, and that allows a fluid to flow only in one direction, and a pressure or an atmospheric pressure generated by the pump. The image recording apparatus according to claim 14, further comprising: a switching valve that selectively supplies the pressure movable part and the suction part.   The pressure supply unit includes a pump that generates an arbitrary pressure, a check valve that is disposed at both ends of the input / output side of the pump, and that allows a fluid to flow in only one direction, and a positive amount that stores an arbitrary amount of pressure higher than atmospheric pressure. A pressure tank, a negative pressure tank that stores an arbitrary amount of pressure lower than atmospheric pressure, and a pressure or atmospheric pressure that is generated by the pump and stored in the positive pressure tank and the negative pressure tank can be selectively supplied. The image recording apparatus according to claim 15, further comprising: a switching valve that controls the flow rate of the pressure supplied from the switching valve, and a flow rate control valve that sends the pressure to the movable movable portion and the suction portion. .