JP2014188829A - Contact state confirmation method, cleaning device for ink jet head and ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact state confirmation method capable of securing cleaning quality by confirming a contact state of a wiping member such as a wiping sheet and an ink jet head.SOLUTION: The contact state confirmation method comprises the steps of: forming step of forming a wet pattern formed of a liquid application area and non-liquid application area by applying liquid on a nozzle face of an ink jet head 120; transferring step of transferring the wet pattern to a wiping member by contacting the wiping member to the nozzle face on which the wet pattern is formed and wiping the nozzle face; and determining step of determining a contact state of the nozzle face and the wiping member by comparing the wet pattern and the pattern transferred on the wiping member.

Description

  The present invention relates to a contact state confirmation method, an inkjet head cleaning apparatus, and an inkjet recording apparatus, and more particularly to a head cleaning technique for wiping a nozzle surface of an inkjet head with a wiping sheet.

  In the ink jet recording apparatus, if the nozzle surface of the head (surface on which the nozzle is formed) is dirty, ejection failure occurs. For this reason, the nozzle surface is periodically cleaned. Conventionally known methods for cleaning the nozzle surface include a method for cleaning the nozzle surface by wiping with a blade, a method for cleaning the nozzle surface by wiping with a web, and the like.

  For example, Patent Document 1 describes a technique in which a wiping sheet impregnated with a cleaning liquid is pressed against a nozzle surface of a droplet discharge head by a pressing roller to wipe the nozzle surface.

Japanese Patent Laid-Open No. 2005-22251

  However, Patent Document 1 does not describe means for confirming the wiping state of the wiping sheet (the contact state between the droplet discharge head and the wiping sheet).

  In particular, when wiping and cleaning using a wiping sheet in the longitudinal direction of a line head that is elongated by arranging and connecting a plurality of head modules in the width direction of the paper, the line head and the wiping sheet It is necessary to check the contact state at the time of installation of the device or at a periodic inspection.

  If the contact state of the wiping sheet is insufficient (for example, per piece) due to the step between the head modules, the flatness of the head, the accuracy of the pressing member (eccentric in the case of a rotating body), etc., the desired cleaning is executed. Therefore, non-ejection caused by accumulation of dirt on the nozzle surface, ejection direction deterioration caused by meniscus destruction inside the nozzle, and in the worst case, the liquid repellent film on the nozzle surface may be damaged.

  The present invention has been made in view of such circumstances, and it is possible to ensure cleaning quality by confirming the contact state between the inkjet head and a wiping member such as a wiping sheet for removing dirt on the inkjet head. An object of the present invention is to provide a contact state confirmation method, an inkjet head cleaning device, and an inkjet recording apparatus.

  In order to achieve the above object, one aspect of the contact state confirmation method includes forming a wet pattern including a liquid application region and a non-liquid application region by applying a liquid to the nozzle surface of the ink jet head; A transfer step of transferring the wet pattern to the wiping member by wiping the wiping member against the nozzle surface on which the pattern is formed and wiping the nozzle surface, and comparing the wet pattern with the pattern transferred to the wiping member And a determination step of determining a state of contact with the wiping member.

  According to this aspect, a liquid is applied to the nozzle surface of the ink jet head to form a wet pattern composed of a liquid application region and a non-liquid application region, and the wiping member is brought into contact with the nozzle surface on which the wet pattern is formed. The wet pattern is transferred to the wiping member by wiping the surface, and the wet pattern and the pattern transferred to the wiping member are compared to determine the contact state between the nozzle surface and the wiping member. Quality can be ensured.

  In the forming step, it is preferable to apply a liquid to the nozzle surface by performing a dummy jet from a plurality of nozzles formed on the nozzle surface. Thereby, it is not necessary to provide a special configuration for applying liquid to the nozzle surface, and a wet pattern can be appropriately formed on the nozzle surface.

  The wet pattern is preferably a striped pattern in which liquid application regions and non-liquid application regions are alternately arranged in the wiping direction of the wiping member. Thereby, the contact state of a wiping member and an inkjet head can be confirmed appropriately.

  Preferably, the forming step forms a plurality of striped patterns having different phases between the liquid application region and the non-liquid application region, and the transfer step preferably transfers the plurality of stripe patterns to the wiping member. Thereby, the contact state of a wiping member and an inkjet head can be confirmed appropriately.

  The ink-jet head is composed of a plurality of head modules, and it is preferable that the striped pattern is formed such that liquid application regions and non-liquid application regions are alternately formed for each adjacent head module. Thereby, the contact state of a wiping member and a head module can be confirmed appropriately.

  A plurality of head modules may be configured to be replaceable. This aspect is also applicable when using an inkjet head composed of a replaceable head module.

  It is preferable that the wiping member has a long shape, and in the cleaning process, the wiping member is pressed against a part of the nozzle surface, the pressing position is moved, and the long wiping member is conveyed in the longitudinal direction. Thereby, while being able to clean a nozzle surface appropriately, the contact state of a wiping member and an inkjet head can be confirmed.

  The liquid applied to the nozzle surface and the wiping member are preferably different in color. Thereby, the state of contact can be determined appropriately.

  A cleaning liquid application step for applying a cleaning liquid to the wiping member may be provided. Thereby, while being able to clean a nozzle surface appropriately, the contact state of a wiping member and an inkjet head can be confirmed.

  In order to achieve the above object, one aspect of the inkjet head cleaning device includes: a cleaning unit that cleans the nozzle surface by abutting and wiping a wiping member against the nozzle surface of the inkjet head; and applying a liquid to the nozzle surface. Forming means for forming a wet pattern composed of a liquid application area and a non-liquid application area, and transfer means for transferring the wet pattern to the wiping member by cleaning the nozzle surface on which the wet pattern is formed by the cleaning means. It was.

  According to this aspect, a liquid is applied to the nozzle surface to form a wet pattern composed of a liquid application region and a non-liquid application region, and the wiping member is pressed against the nozzle surface on which the wet pattern is formed to wipe the wet pattern. Since the image is transferred to the member, the contact state between the wiping member and the inkjet head can be confirmed, and the cleaning quality can be ensured.

  It is preferable to include a scanner that reads the pattern transferred to the wiping member, and a determination unit that compares the wet pattern with the read pattern to determine the contact state between the nozzle surface and the wiping member in the cleaning unit. Accordingly, it is possible to appropriately determine the contact state regardless of human eyes.

  In order to achieve the above object, one aspect of an ink jet recording apparatus includes an ink jet head having a nozzle surface provided with a plurality of nozzles for ejecting ink, and a plurality of nozzles while relatively moving the ink jet head and the recording medium. A recording unit that discharges ink to record an image on a recording medium, a pressing unit that presses the wiping member against a part of the nozzle surface of the inkjet head, a moving unit that moves the pressing position of the inkjet head and the wiping member, Conveying means for conveying the wiping member, forming means for applying a liquid to the nozzle surface to form a wet pattern composed of a liquid application region and a non-liquid application region, and pressing the wiping member against the nozzle surface on which the wet pattern is formed And moving the pressing position between the inkjet head and the wiping member and transporting the wiping member to And a transfer unit for transferring the 拭部 material.

  According to this aspect, a liquid is applied to the nozzle surface to form a wet pattern composed of a liquid application region and a non-liquid application region, and the wiping member is pressed against the nozzle surface on which the wet pattern is formed to wipe the wet pattern. Since the image is transferred to the member, the contact state between the wiping member and the inkjet head can be confirmed, and the cleaning quality can be ensured.

  According to the present invention, it is possible to confirm the contact state between the wiping member and the inkjet head and to ensure the cleaning quality.

Side view showing an inkjet recording apparatus Plan view of inkjet recording apparatus Schematic diagram showing the schematic configuration of the wiping unit Plan view showing structural example of head Partial enlarged view of FIG. Plan view showing nozzle arrangement of head module Cross-sectional view of recording element corresponding to one nozzle Block diagram showing system configuration of inkjet recording apparatus Flow chart showing processing of contact confirmation method Schematic diagram showing the nozzle surface with a wet pattern formed FIG. 10 is a schematic diagram showing a nozzle surface on which a wet pattern having a phase different from that of FIG. 10 is formed. Schematic diagram showing the nozzle surface with a wet pattern formed FIG. 13 is a schematic diagram showing a nozzle surface on which a wet pattern having a phase different from that of FIG. 13 is formed. Schematic showing the nozzle surface with other wet patterns formed

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

<Embodiment>
[Outline of inkjet recording apparatus]
FIG. 1 is a side view showing an ink jet recording apparatus according to the present embodiment. The ink jet recording apparatus 100 forms an image by ejecting ink from the nozzle surface 130 of the ink jet head 120 onto the recording surface of the paper 1 (an example of a recording medium) transported in the horizontal direction (Y direction) by the transport unit 110. It is a printer.

  FIG. 2 is a plan view of the ink jet recording apparatus 100. The ink jet recording apparatus 100 includes a moisturizing cap 180 and a wiping unit 200 in a direction (X direction) orthogonal to the transport direction (Y direction) of the paper 1 by the transport unit 110.

  The inkjet head 120 is configured to be movable in the X direction by a head moving mechanism (not shown). When the apparatus is stopped for a long time, the inkjet head 120 is moved from a position where the image can be formed on the paper 1 (image forming position) to the position of the moisture retaining cap 180 (humidity retaining position), and the nozzle surface 130 is moved to the moisture retaining cap 180. Covered with. Thereby, non-ejection due to drying is prevented.

  The moisturizing cap 180 is provided with a pressurizing / suction mechanism (not shown) for pressurizing and sucking the inside of the nozzle, and a cleaning liquid supply mechanism (not shown) for supplying a cleaning liquid into the moisturizing cap 180.

  The wiping unit 200 (an example of a cleaning unit) is disposed between the transport unit 110 and the moisturizing cap 180. The wiping unit 200 cleans the nozzle surface 130 by wiping the nozzle surface 130 of the inkjet head 120 with a wiping web to which the cleaning liquid is applied when the inkjet head 120 moves from the image forming position to the moisturizing position.

[Overview of wiping unit]
FIG. 3 is a schematic diagram illustrating a schematic configuration of the wiping unit 200. As shown in the figure, the wiping unit 200 is driven to rotate by a sending-side web core 202 that sends out the wiping web 201 before wiping, and a take-up motor (not shown). A winding side web core 203 to be wound up, a first guide roll 204 that rotates in contact with the wiping web 201 delivered from the delivery side web core 202 and guides to the cleaning liquid application unit 205, and a predetermined amount on the wiping web 201. A cleaning liquid applying unit 205 that applies the cleaning liquid 205 a, a second guide roll 206 that rotates in contact with the wiping web 201 delivered from the cleaning liquid applying unit 205, and guides the wiping web 201 to the pressing roll 207. A pressure roll 207 that makes contact with the nozzle surface 130 with a predetermined pressure, and a wiping web that wipes the nozzle surface 130 A scanner 210 capable of reading surface (wiping surface) 01 configured to include a.

  The wiping web 201 is composed of a sheet made of knitting or weaving using ultrafine fibers such as polyethylene terephthalate, polyethylene, nylon, etc., and is formed in a strip shape having a width corresponding to the width of the nozzle surface 130 of the inkjet head 120. Is done. The wiping web 201 is provided in a state in which the wiping web 201 is wound around the delivery-side web core 202 in a roll shape and the tip is fixed to the take-up-side web core 203.

  The delivery-side web core 202 is fitted and attached to a delivery shaft (not shown) that is fixed at one end and supported horizontally. The delivery shaft has a double tube structure, and an outer cylinder is rotatably supported around the inner cylinder. A reverse rotation prevention mechanism and a friction mechanism are arranged between the inner cylinder and the outer cylinder, and the outer cylinder is configured to rotate only in one direction (the feeding direction of the wiping web 201) with a certain resistance.

  The winding-side web core 203 is fitted and mounted on a winding shaft (not shown) that is rotatably supported horizontally. A winding motor is connected to the winding shaft, and the winding-side web core 203 is driven by the winding motor to rotate in one direction (winding direction of the wiping web 201).

  The take-up shaft has a double structure, and an outer cylinder is rotatably supported around the inner cylinder. A torque limiter is disposed between the inner cylinder and the outer cylinder, and is configured such that the outer cylinder slides with respect to the inner cylinder when a load (torque) exceeding a certain level is applied. Thereby, it is possible to prevent excessive tension from being applied to the wiping web 201.

  The first guide roll 204 is rotatably supported by a horizontally installed shaft (not shown) and guides the wiping web 201 delivered from the delivery-side web core 202 toward the cleaning liquid application unit 205.

  The cleaning liquid applying unit 205 jets the cleaning liquid 205 a from the cleaning liquid nozzle to the wiping web 201, and quantitatively applies the cleaning liquid 205 a to the wiping web 201. The method of applying the cleaning liquid 205a to the wiping web 201 is not limited to spraying from the cleaning liquid nozzle. For example, the aspect provided using an anilox roll etc. can be considered.

  The second guide roll 206 is rotatably supported by a horizontally installed shaft (not shown), and guides the wiping web 201 delivered from the cleaning liquid applying unit 205 toward the pressing roll 207.

  The pressing roll 207 is horizontally installed with one end of its shaft portion rotatably supported. The pressing roll 207 is composed of a rubber roll corresponding to the width of the wiping web 201, and the wiping web 201 is brought into contact with the nozzle surface 130 of the inkjet head 120 with a predetermined pressure by the urging force of the spring 208.

  The scanner 210 is disposed to face the wiping web 201 that is wound around the winding side web core 203 from the pressing roll 207. The scanner 210 has a width (length in the Y direction) that can read the entire width of at least the nozzle surface 130 of the wiping web 201, and reads the state of dirt on the surface of the wiping web 201.

[Operation of wiping unit]
Next, the operation of the wiping unit 200 configured as described above will be described.

  The operation of the wiping unit 200 is controlled by a control device that controls the entire inkjet recording apparatus 100. The control device wipes and cleans the nozzle surface 130 by the wiping unit 200 in the process of moving the inkjet head 120 from the image recording position to the moisturizing position.

  The entire wiping unit 200 is configured to be movable up and down by a wiping device main body lifting mechanism. The wiping unit 200 is positioned at a predetermined standby position except during cleaning, and is positioned at a predetermined operating position that is a position raised by a predetermined amount from the standby position during cleaning.

  In a state where the wiping unit 200 is located at the operating position, the wiping unit 200 can wipe the nozzle surface 130 of the inkjet head 120. That is, when the inkjet head 120 passes through the wiping unit 200, the wiping web 201 wound around the pressure roll 207 can be pressed against the nozzle surface 130.

  The control device controls the conveyance of the wiping web 201 by controlling the driving of the winding motor in accordance with the timing at which the inkjet head 120 reaches the wiping unit 200. Thereby, the wiping web 201 is unrolled from the sending-side web core 202 and travels, and is taken up by the winding-side web core 203.

  At this time, the feeding shaft of the feeding-side web core 202 is given friction by the friction mechanism, while the winding shaft of the winding-side web core 203 slips when a certain load is applied by the torque limiter. It is possible to run the vehicle with a certain tension applied thereto.

  The control device controls the cleaning liquid application unit 205 simultaneously with the traveling of the wiping web 201 to wet the wiping web 201 with the cleaning liquid 205a. The amount of cleaning liquid appropriate for the wiping web 201 (the amount suitable for wiping the nozzle surface 130) is the absorption capacity of the wiping web 201, the liquid repellency (ink contact angle) of the nozzle surface 130, the ink physical properties, and the nozzle diameter. It depends on. Therefore, the cleaning liquid 205a may be ejected from the cleaning liquid application unit 205 according to the amount of cleaning liquid required.

  Thereby, the wiping web 201 can be brought into a wet state with an appropriate amount of the cleaning liquid 205a, and the wiping web 201 has an optimum absorption capacity. As a result, it is possible to prevent the cleaning liquid 205a from entering the liquid and sag of the nozzle surface 130 when wiping the nozzle surface 130.

  The wiping web 201 to which the cleaning liquid 205a is given in this manner is guided to the pressing roll 207 by the second guide roll 206, and is pressed against the nozzle surface 130 on the pressing roll 207 by driving by the winding motor, and the nozzle Surface 130 is wiped and cleaned.

  At this time, the wiping web 201 travels in the direction opposite to the moving direction of the nozzle surface 130 and wipes the nozzle surface 130. Thereby, the nozzle surface 130 can be wiped off efficiently. Further, the nozzle surface 130 can always be wiped using a new surface (unused area) of the wiping web 201.

  The wiping web 201 wiping the nozzle surface 130 is wound on the winding side web core 203. At this time, the surface of the wiping web 201 is read by the scanner 210. In addition, the inkjet head 120 is moved to the moisturizing position by the head moving mechanism, and the nozzle surface 130 is covered with the moisturizing cap 180.

[Inkjet head structure]
Next, an example of the structure of the inkjet head 120 (hereinafter referred to as the head 120) will be described. FIG. 4 is a plan view showing an example of the structure of the head 120, and is a view of the head 120 as viewed from the nozzle surface 130 side. FIG. 5 is a partially enlarged view of FIG.

  As shown in FIG. 4, the head 120 has a structure in which 17 head modules 120-i (i = 1 to 17) are connected along the X direction, and extends over a length corresponding to the entire width of the paper 1. A plurality of nozzles (not shown in FIG. 4) are provided.

  Each head module 120-i is configured to be replaceable, and is supported by a head module support member 120B from both sides of the head 120 in the short direction. Further, both end portions of the head 120 in the longitudinal direction are supported by a head support member 120D.

  As shown in FIG. 5, each head module 120-i has a structure in which a plurality of nozzles are arranged in a matrix (two-dimensional). An oblique solid line denoted by reference numeral 142 in FIG. 5 represents a nozzle row in which a plurality of nozzles are arranged in a row.

  FIG. 6 is a plan view showing the nozzle arrangement of the head module 120-i. As shown in the figure, the head module 120-i has a number of nozzles 140 arranged in a matrix along a column direction W that forms an angle α with respect to the Y direction and a row direction V that forms an angle β with respect to the X direction. The substantial nozzle arrangement density in the X direction is increased. In FIG. 6, the nozzle group (nozzle row) arranged along the column direction W is denoted by reference numeral 144, and the nozzle group (nozzle row) arranged along the row direction V is denoted by reference numeral 146.

  The nozzle arrangement applicable to the present embodiment is not limited to the nozzle arrangement illustrated in FIG. 6, for example, along the row direction along the X direction and the column direction oblique to the X direction and the Y direction. The present invention can also be applied to an embodiment in which a plurality of nozzles are arranged in a matrix.

  FIG. 7 is a cross-sectional view of a recording element corresponding to one nozzle 140. As shown in the figure, the head 120 (head module 120-i) of this example includes a nozzle plate 144 in which a nozzle 140 is formed, and a flow path in which flow paths such as a pressure chamber 146 and a common flow path 148 are formed. It has a structure in which plates 150 and the like are laminated and joined. The nozzle plate 144 constitutes a part of the nozzle surface 130 of the head 120, and a plurality of nozzles 140 communicating with the pressure chambers 146 are two-dimensionally formed.

  The flow path plate 150 constitutes a side wall portion of the pressure chamber 146 and forms a supply port 152 as a throttle portion (most narrowed portion) of an individual supply path that guides ink from the common flow path 148 to the pressure chamber 146. It is a forming member. For convenience of explanation, the flow path plate 150 has a structure in which one or a plurality of substrates are stacked, although it is illustrated schematically in FIG.

  The nozzle plate 144 and the flow path plate 150 can be processed into a required shape by a semiconductor manufacturing process using silicon as a material.

  The common flow path 148 communicates with an ink tank (not shown) that is an ink supply source, and the ink supplied from the ink tank is supplied to each pressure chamber 146 via the common flow path 148.

  A diaphragm 154 constituting a part of the pressure chamber 146 (the top surface in FIG. 7) includes an individual electrode 156 and a lower electrode 158, and the piezoelectric body 160 is sandwiched between the individual electrode 156 and the lower electrode 158. A piezoelectric actuator 162 having the above structure is joined. When the diaphragm 154 is formed of a metal thin film or a metal oxide film, it functions as a common electrode corresponding to the lower electrode 158 of the piezoelectric actuator 162. In the aspect in which the diaphragm is formed of a non-conductive material such as resin, a lower electrode layer made of a conductive material such as metal is formed on the surface of the diaphragm member.

  By applying a driving voltage to the individual electrode 156, the piezo actuator 162 is deformed to change the volume of the pressure chamber 146, and ink is ejected from the nozzle 140 due to the pressure change accompanying this. When the piezo actuator 162 returns to its original state after ink ejection, new ink is refilled into the pressure chamber 146 from the common flow path 148 through the supply port 152.

  The high-density nozzle head of this example is realized by arranging a large number of ink chamber units having such a structure in a lattice pattern with a fixed arrangement pattern as shown in FIG. In such a matrix arrangement, when the interval between adjacent nozzles in the Y direction is Ls, the nozzles 140 in the X direction are treated substantially equivalently to those in which the nozzles 140 are arranged linearly at a constant pitch P = Ls / tan θ. Can do.

  In this example, the piezo actuator 162 is applied as a means for generating ink ejection force to be ejected from the nozzles 140 provided in the head 120. However, a heater is provided in the pressure chamber 146, and the pressure of film boiling caused by heating of the heater is used. It is also possible to apply a thermal method that ejects ink.

[System configuration of inkjet recording apparatus]
FIG. 8 is a block diagram showing a system configuration of the inkjet recording apparatus 100. As shown in FIG. 1, the inkjet recording apparatus 100 includes an image recording unit 300 that records an image on a sheet 1 and a control unit 310 that controls the image recording unit 300.

  The image recording unit 300 includes an ink supply unit 170, a moving mechanism 190, and the like in addition to the transport unit 110, the head 120, the moisturizing cap 180, the wiping unit 200, and the scanner 210 described above.

  The ink supply unit 170 includes an ink tank and a pump (not shown), and supplies the ink discharged from the nozzles 140 of the head 120 to the head 120. The moving mechanism 190 moves the inkjet head 120 to an image recording position or a moisture retention position.

  The control unit 310 includes a user interface 312, a recording control unit 314, a cleaning control unit 316, a contact determination unit 318, and the like, and performs overall control of the inkjet recording apparatus 100.

  The user interface 312 has an input unit (not shown) for the user to operate the inkjet recording apparatus 100 and an output unit (not shown) for displaying a warning display or the like.

  A recording control unit 314 (an example of a recording unit) controls the conveyance of the paper 1 by the conveyance unit 110, the ejection of ink by the head 120, the supply of ink to the head 120 by the ink supply unit 170, and the like.

  The cleaning control unit 316 moves the head 120 between the image forming position and the moisturizing position by the moving mechanism 190, wipes and cleans the nozzle surface 130 of the head 120 by the wiping unit 200, supplies moisturizing liquid to the moisturizing cap 180, and at the moisturizing position. Control such as pressure purge for discharging ink from all nozzles is performed.

  The contact determination unit 318 determines the contact state between the pressing roll 207 of the wiping unit 200 and the nozzle surface 130 of the head 120 based on the input reading result of the scanner 210.

  The control unit 310 performs overall control of the inkjet recording apparatus 100. For example, in addition to the conveyance of the paper 1 by the conveyance unit 110, the image recording by the inkjet head 120, the movement of the inkjet head 120 to the moisturizing position by the moving mechanism 190, the wiping cleaning of the nozzle surface 130 by the wiping unit 200, the ejection of normal ink And a pressure purge that discharges ink from all nozzles of the inkjet head 120, which are different from the above, are controlled.

[Checking method of pressing roll contact]
FIG. 9 is a flowchart showing the process of the contact confirmation method between the nozzle surface and the wiping web according to the present embodiment. This contact confirmation is performed when the user sets the contact confirmation mode through the user interface 312. Alternatively, it may be performed when the inkjet recording apparatus 100 is turned on.

(Step S1)
First, the cleaning control unit 316 (an example of a forming unit) moves the head 120 to the moisturizing position by the moving mechanism 190. At the moisturizing position, dummy jets (preliminary ejection, pre-discharge, from all nozzles 140 of the head modules 120-1, 3, 5, 7, 9, 11, 13, 15, 17 (odd-numbered head modules) of the head 120 are provided. Ink is discharged (an example of a forming process).

  FIG. 10A is a schematic diagram showing the nozzle surface 130 of the head 120 at this time. As shown in the figure, ink mist by a dummy jet adheres to the areas of the head modules 120-1, 3, 5, 7, 9, 11, 13, 15, 17 on the nozzle surface 130 (in the liquid application area). An example), which is not attached to the area of the head modules 120-2, 4, 6, 8, 10, 12, 14, 16 (an example of a non-liquid application area). As described above, the liquid application area and the non-liquid application area on the nozzle surface 130 are wiped in the wiping direction of the wiping web 201 by the dummy jets in the head modules 120-1, 3, 5, 7, 9, 11, 13, 15, and 17. A striped wet pattern arranged alternately is formed. Here, the width (Y-direction length) of the head 120 is d. In this step, ink is ejected from all the nozzles 140 of the head modules 120-1, 3, 5, 7, 9, 11, 13, 15, and 17. If it can adhere, it is not necessary to use all the nozzles 140.

(Step S2)
Next, the cleaning control unit 316 (an example of a transfer unit) moves the head 120 to the image forming position by the moving mechanism 190 and further moves from the image forming position to the moisturizing position. At this time, the wiping unit 200 wipes and cleans the nozzle surface 130 of the head 120 and transfers the striped wet pattern formed on the nozzle surface 130 to the wiping web 201 (an example of a transfer process).

  That is, in the wiping web 201, the ink mist is applied to a portion of the nozzle surface 130 where the area of the head module 120-1, 3, 5, 7, 9, 11, 13, 15, 17 to which the ink mist has adhered is wiped. The ink mist does not adhere to the portion where the area of the head modules 120-2, 4, 6, 8, 10, 12, 14, and 16 to which the ink mist adheres and does not adhere is wiped. Therefore, the striped wet pattern formed on the nozzle surface 130 is transferred to the wiping web 201.

(Step S3)
At the same time, the scanner 210 continuously reads the wiping surface of the wiping web 201 passing through the position facing the scanner 210, and outputs the read image data to the contact determination unit 318.

  FIG. 10B is a schematic diagram showing an example of the read image data. As shown in the figure, the read image data includes a wet pattern transferred to the wiping web 201. That is, among the wiping surfaces of the wiping web 201, the head modules 120-1, 3, 5, 7, 9, 11, 13, 15, and 17 are respectively wiped and the areas 220-1, 3, and 3 where the ink mist is transferred. The data of 5, 7, 9, 11, 13, 15, 17 are included.

  In the read image data, the color of the ink and the color of the wiping web 201 are preferably different so that the transfer area and the non-transfer area can be easily distinguished. In particular, the color of the wiping web 201 is preferably white.

(Step S4)
The contact determination unit 318 (an example of a determination unit) determines the contact between each head module 120-1,3,5,7,9,11,13,15,17 of the head 120 and the pressure roll 207 from the read image data. A state is judged (an example of a judgment process). If the contact state is normal, the wet pattern formed in advance and the pattern transferred to the wiping web 201 have a corresponding relationship. That is, each area of the transferred pattern has a module width d in the width direction (Y direction) of the wiping web 201, and the length direction (conveyance direction) is the pressing roll 207 with respect to the X direction length of the head module. And a length corresponding to the moving speed of the head 120. Therefore, by comparing the wet pattern and the transferred pattern, the contact state between each head module 120-i and the pressing roll 207 can be determined.

  For example, as shown in FIG. 10C, when the pressing roll 207 is in contact with the head module 120-i in the Y direction, the width direction of the head 120 in the region 220-i in the transferred pattern. The length is shorter than d (the figure shows a state where it is shorter by Δd). In this manner, the contact determination unit 318 analyzes the X direction length and the Y direction width for each region of the read image data.

  When the contact determination unit 318 finds an area where the wet pattern is not properly transferred, the head module 120-i cannot normally contact the pressing roll 207 at the output unit (not shown) of the user interface 312. A warning to that effect is output.

  The user who sees this warning adjusts the head module 120-i in the height direction (distance direction with respect to the paper 1) to normalize the contact state between the head module 120-i and the pressing roll 207. be able to.

(Step S5)
Subsequently, the cleaning control unit 316 has all the head modules 120-2, 4, 6, 8, 10, 12, 14, and 16 (even-numbered head modules) of the head 120 in a state where the head 120 is in the moisture retaining position. Ink is ejected from the nozzle 140 by a dummy jet.

  FIG. 11A is a schematic diagram showing the nozzle surface 130 of the head 120 at this time. As shown in the figure, ink mist by a dummy jet adheres to the areas of the head modules 120-2, 4, 6, 8, 10, 12, 14, 16 in the nozzle surface 130, and the head modules 120-1, It is not attached to the regions 3, 5, 7, 9, 11, 13, 15, and 17. As described above, the striped wet pattern having a phase different from that of the dummy jet in step S1 is formed on the nozzle surface 130 by the dummy jets in the head modules 120-2, 4, 6, 8, 10, 12, 14, and 16. It is formed.

(Step S6)
Next, the cleaning control unit 316 moves the head 120 to the image forming position by the moving mechanism 190, and further moves from the image forming position to the moisturizing position. At this time, the nozzle surface 130 of the head 120 is wiped and cleaned by the wiping unit 200, and the striped wet pattern formed on the nozzle surface 130 is transferred to the wiping web 201.

  In other words, the ink mist adheres to the wiping web 201 on the portion of the nozzle surface 130 where the area of the head module 120-2, 4, 6, 8, 10, 12, 14, 16 where the ink mist adheres is wiped. The ink mist does not adhere to the areas where the areas of the head modules 120-1, 3, 5, 7, 9, 11, 13, 15, and 17 to which the ink mist is not attached are formed on the nozzle surface 130. A striped wet pattern is transferred.

(Step S7)
At the same time, the scanner 210 continuously reads the wiping surface of the wiping web 201 passing through the position facing the scanner 210, and outputs the read image data to the contact determination unit 318.

  FIG. 11B is a schematic diagram showing an example of the read image data. As shown in the figure, the read image data includes a wet pattern transferred to the wiping web 201. That is, in the wiping surface of the wiping web 201, the head modules 120-2, 4, 6, 8, 10, 12, 14, and 16 are wiped, and the regions 220-2, 4, 6, and 6 where the ink mist is transferred. It has 8, 10, 12, 14, and 16 data.

(Step S8)
The contact determination unit 318 determines the contact state between the head modules 120-2, 4, 6, 8, 10, 12, 14, and 16 of the head 120 and the pressing roll 207 from the read image data. When the contact determination unit 318 finds an area where the wet pattern is not properly transferred, the head module 120-i cannot normally contact the pressing roll 207 at the output unit (not shown) of the user interface 312. A warning to that effect is output.

  The user who sees this warning adjusts the head module 120-i in the height direction (distance direction with respect to the paper 1) to normalize the contact state between the head module 120-i and the pressing roll 207. be able to.

  In this way, a wet pattern consisting of an area where liquid is applied to the nozzle surface of the inkjet head and an area where liquid is not applied is formed, and the area where liquid is applied by wiping and cleaning the nozzle surface where the wet pattern is formed The liquid is transferred to the wiping web, and the contact state between the wiping web and the inkjet head is determined by determining the state of contact between the nozzle surface and the wiping web based on the pattern transferred to the wiping web (with the press roll). It is possible to guarantee the contact state with the nozzle surface.

[Modification of wet pattern]
FIG. 12A is a schematic diagram illustrating a modification of the striped wet pattern formed on the nozzle surface 130. As shown in the figure, the area 120 -i-D on the downstream side in the Y direction of the head modules 120-1, 3, 5, 7, 9, 13, 15, 17 on the nozzle surface 130, and the head module 120 -2,4,6,8,10,12,14,16 in the Y-direction upstream region 120-i-U is a liquid application region, and the other region is a non-liquid application region; It has become. This wet pattern can be formed by performing a dummy jet with a nozzle arranged in a region to be a liquid application region.

  FIG. 12B is a schematic diagram showing an example of read image data in which the wet pattern shown in FIG. 12A is transferred to the wiping surface of the wiping web 201 and the wiping surface is continuously read by the scanner 210. FIG. As shown in the figure, the read image data is an area 222 where the ink mist is transferred by wiping each of the areas 120-i-D and 120-i-U, which are liquid application areas, of the wiping surface of the wiping web 201. -I-D, 222-i-U data is included.

  The contact determination unit 318 can determine the contact state between each head module 120-i (i = 1 to 17) of the head 120 and the pressure roll 207 from the read image data.

  Further, FIG. 13A is a schematic diagram showing a wet pattern having a phase different from that of the wet pattern shown in FIG. As shown in FIG. 13A, the head module 120-2, 4, 6, 8, 10, 12, 14, and 16 in the Y direction downstream side of the nozzle module 130, and the head module. 120-1,3,5,7,9,11,13,15,17 A region 120-i-U upstream in the Y direction is a liquid application region, and the other regions are non-liquid application regions. It has a wet pattern. This wet pattern can also be formed by performing a dummy jet with a nozzle arranged in a region to be a liquid application region.

  FIG. 13B is a schematic diagram illustrating an example of read image data in which the wet pattern shown in FIG. 13A is transferred to the wiping surface of the wiping web 201 and the wiping surface is continuously read by the scanner 210. FIG. As shown in the figure, the read image data is an area 222 where the ink mist is transferred by wiping each of the areas 120-i-D and 120-i-U, which are liquid application areas, of the wiping surface of the wiping web 201. -I-D, 222-i-U data is included.

  The contact determination unit 318 can determine the contact state between each head module 120-i (i = 1 to 17) of the head 120 and the pressure roll 207 from the read image data.

  In addition, as shown in FIG. 14A, in all the head modules 120-i, a liquid application region 124-i that is a part of the X direction and reaches from the upstream side in the Y direction to the downstream side is provided. It is also possible to adopt a striped wet pattern in the X direction.

  Alternatively, every X head modules 120-i may be used as a liquid application region, and (X + 1) striped wet patterns having different phases may be generated. FIG. 14B shows a wetting pattern when X = 2, and the head modules 120-1, 4, 7, 10, 13, 16 are used as liquid application regions. In addition, the wet pattern in which the head modules 120-2, 5, 8, 11, 14, and 17 having different phases are used as the liquid application regions, and the head modules 120-3, 6, 9, 12, and 15 are used as the liquid application regions. By using the wet pattern, the contact state can be confirmed. Thus, various modes can be used as the striped wet pattern.

  In the present embodiment, the pattern transferred to the wiping web 201 is read by the scanner 210, and the contact determination unit 318 determines the contact state based on the read image data, but the user is transferred to the wiping web 201. The contact state may be confirmed by visually recognizing the pattern.

  Further, in the present embodiment, the contact state of each head module is confirmed by forming a striped pattern consisting of a liquid application region and a non-liquid application region on the nozzle surface, but the entire nozzle surface is a liquid application region, You may confirm the contact state of each head module by the density of the pattern transcribe | transferred to the wiping web.

  In addition, the mode of applying the liquid to the nozzle surface is not limited to the dummy jet, and by controlling the ink back pressure for each head module in the ink supply unit, the ink is allowed to overflow from the nozzle to the nozzle surface (addition). The liquid application region on the nozzle surface may be formed by a liquid application means such as a pressure purge) or a nozzle disposed opposite to the inkjet head.

  In this embodiment, up to the head module support member 120B in the nozzle surface 130 is the liquid application region, but only the region where the nozzles are arranged may be the liquid application region. Even in this case, the contact state can be confirmed by comparing the formed wet pattern and the pattern transferred to the wiping web.

  The technical scope of the present invention is not limited to the scope described in the above embodiment. The configurations and the like in the embodiments can be appropriately combined between the embodiments without departing from the gist of the present invention.

  DESCRIPTION OF SYMBOLS 100 ... Inkjet recording device 110 ... Conveyance part, 120 ... Inkjet head, 130 ... Nozzle surface, 140 ... Nozzle, 170 ... Ink supply part, 180 ... Moisturizing cap, 190 ... Moving mechanism, 200 ... Wiping unit, 201 ... Wiping web 207 ... Pressing roll 210 ... Scanner 314 ... Recording control unit 316 ... Cleaning control unit 318 ... Abutting judgment unit

Claims (12)

Forming a wet pattern comprising a liquid application region and a non-liquid application region by applying liquid to the nozzle surface of the inkjet head; and
A transfer step of transferring the wet pattern to the wiping member by wiping the nozzle surface by bringing a wiping member into contact with the nozzle surface on which the wet pattern is formed;
A determination step of comparing the wet pattern and the pattern transferred to the wiping member to determine a contact state between the nozzle surface and the wiping member;
A contact state confirmation method comprising:   The contact state confirmation method according to claim 1, wherein the forming step applies liquid to the nozzle surface by performing a dummy jet from a plurality of nozzles formed on the nozzle surface.   The contact state confirmation method according to claim 1, wherein the wet pattern is a striped pattern in which the liquid application area and the non-liquid application area are alternately arranged in the wiping direction of the wiping member. The forming step forms a plurality of striped patterns having different phases between the liquid application region and the non-liquid application region,
The contact state confirmation method according to claim 3, wherein the transferring step transfers the plurality of striped patterns to the wiping member. The inkjet head is composed of a plurality of head modules,
5. The contact state confirmation method according to claim 3, wherein the stripe pattern is formed such that the liquid application region and the non-liquid application region are alternately formed for each adjacent head module.   The contact state confirmation method according to claim 5, wherein the plurality of head modules are configured to be replaceable. The wiping member is elongated,
The said transfer process presses the said wiping member to a part of said nozzle surface, moves a pressing position, and conveys the said elongate wiping member to a longitudinal direction. The contact state confirmation method.   The contact state confirmation method according to any one of claims 1 to 7, wherein the liquid applied to the nozzle surface and the wiping member have different colors.   The contact state confirmation method according to claim 1, further comprising a cleaning liquid application step of applying a cleaning liquid to the wiping member. Cleaning means for cleaning the nozzle surface by abutting and wiping a wiping member on the nozzle surface of the inkjet head;
Forming means for applying a liquid to the nozzle surface to form a wet pattern composed of a liquid application region and a non-liquid application region;
Transfer means for transferring the wet pattern to the wiping member by cleaning the nozzle surface on which the wet pattern is formed by the cleaning means;
Inkjet head cleaning device comprising: A scanner for reading the pattern transferred to the wiping member;
A determination unit that compares the wet pattern with the read pattern to determine a contact state between the nozzle surface and the wiping member in the cleaning unit;
The inkjet head cleaning device according to claim 10, further comprising: An inkjet head having a nozzle surface provided with a plurality of nozzles for discharging ink;
Recording means for recording an image on the recording medium by ejecting ink from the plurality of nozzles while relatively moving the inkjet head and the recording medium;
A cleaning device for an inkjet head according to claim 10 or 11,
An ink jet recording apparatus comprising: