JP2012176545A - Wiping unit, maintenance device, liquid ejector, and wiping method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiping unit, a maintenance device, a liquid ejector, and a wiping method, in which wet wiping is adopted as wiping for an ejection surface of a liquid ejection head whereby the cleaning performance of a predetermined ejecting surface is maintained, and durability of the predetermined ejecting surface is maintained.SOLUTION: The wiping unit includes a web (62) which is brought into contact with a nozzle surface (51A) of an ink jet head (41) to wipe up the liquid ejecting surface, means for moving the web to the liquid ejecting surface, a cleaning liquid spray head provided upstream of the position where the liquid ejecting surface and the web are come into contact in the transfer path of the web and spraying a cleaning liquid to the moving web, a first temperature sensor (94) and a second temperature sensor (96) for detecting unevenness of the cleaning liquid applied by the web to which the cleaning liquid is sprayed by a cleaning liquid spray head.

Description

  The present invention relates to a wiping unit, a maintenance device, a liquid ejection device, and a wiping method, and in particular, a wiping unit for wiping a liquid ejection head represented by an inkjet head, a maintenance device, and a liquid ejection device (drawing device) including the same. About.

  2. Description of the Related Art There are known a method and an apparatus for manufacturing an organic EL device by forming functional liquid into fine droplets using an ink jet type liquid discharge head (ink jet head). In such a manufacturing method (apparatus), a liquid light-emitting material is introduced as a functional liquid into an ink jet recording apparatus, and this is ejected to a large number of pixel regions. Thereafter, a solvent in the light-emitting material is vaporized (dried), and organic EL The light emitting layer is formed.

  In liquid discharge using an ink jet head, if there are deposits in the vicinity of the nozzle openings formed in the ink jet head, discharge abnormalities such as flying bends of liquid droplets discharged from the ink jet head and variations in the appropriate amount of liquid may occur. .

  In particular, in a configuration in which a functional liquid having a higher viscosity than water-based ink used for image drawing is used, mist generated at the time of ejection tends to adhere to the ejection surface. In order to remove such deposits attached to the discharge surface, a wiping process is performed on the discharge surface by a wiping member such as a web or a wiper.

  Patent Document 1 includes a cleaning liquid spray head that impregnates a wiping sheet by spraying a cleaning liquid, and is configured to perform a wiping operation of the nozzle forming surface of the functional liquid droplet ejection head while running the wiping sheet impregnated with the cleaning liquid. A wiping unit is disclosed.

JP 2004-167488 A

  However, when the wiping process is performed on the ejection surface, if both the ejection surface and the wiping member are in a dry state, dry wiping is caused, and there is a concern that the performance of removing the deposits may deteriorate. In addition, there is a concern that the protective (liquid repellent) film on the ejection surface and the wiping member are worn or damaged.

  In the wiping unit disclosed in Patent Document 1, the wiping sheet is impregnated with a cleaning liquid before wiping the nozzle forming surface of the functional liquid droplet ejection head, but the cleaning liquid is applied to the wiping sheet. Not sure that.

  Then, if a situation occurs in which the cleaning liquid is not applied to the wiping sheet due to some trouble, the wiping process becomes substantially dry wiping, and the desired wiping (cleaning performance) cannot be exhibited, and deposits on the nozzle forming surface Is accumulated, and abnormal discharge is induced.

  In addition, there is a possibility that the protection film on the nozzle forming surface may be worn out, the protection film on the nozzle forming surface may be damaged, and the durability of the nozzle forming surface may be significantly reduced.

  The present invention has been made in view of such circumstances. The wiping of the discharge surface of the liquid discharge head is used as wet wiping, so that the cleaning performance of the predetermined discharge surface is maintained and the durability of the predetermined discharge surface is maintained. An object is to provide a wiping unit, a maintenance device, a liquid ejection device, and a wiping method that are maintained.

  In order to achieve the above object, a wiping unit according to the present invention includes a sheet-like wiping member that wipes the liquid ejection surface by contacting the liquid ejection surface of an inkjet head, and the wiping member on the liquid ejection surface. And a wiping member disposed on the upstream side of the contact position between the liquid ejection surface and the wiping member of the moving path of the wiping member in the moving unit and moved by the moving unit. A cleaning liquid spraying means for spraying the cleaning liquid on the collecting member; and a detecting means for detecting at least unevenness of the cleaning liquid in the moving direction of the moving means in the wiping member sprayed with the cleaning liquid by the cleaning liquid spraying means. Features.

  According to the present invention, the wet state of the wiping member by the cleaning liquid is grasped by detecting at least the unevenness of the cleaning liquid in the moving direction of the moving means (wiping member) in the wiping member to be brought into contact with the nozzle surface of the inkjet head. can do.

1 is an overall configuration diagram showing a schematic configuration of an ink jet recording apparatus to which a wiping unit according to the present invention is applied. The top view which shows the structure of the printing part of the inkjet recording device shown in FIG. Plane perspective view showing an example of the structure of the inkjet head shown in FIG. The figure explaining the nozzle arrangement of the inkjet head shown in FIG. Sectional drawing which shows the three-dimensional structure of the inkjet head shown in FIG. Explanatory drawing which shows typically the example of arrangement | positioning of the wiping unit in the inkjet recording device shown in FIG. The block diagram which shows schematic structure of the wiping unit which concerns on 1st Embodiment of this invention. Explanatory drawing which illustrated typically the wiping process by the wiping unit shown in FIG. Explanatory drawing which shows the relationship between the spray area | region of a washing | cleaning liquid, and the measurement area | region of a temperature sensor 1 is a block diagram showing a schematic configuration of a control system of the ink jet recording apparatus shown in FIG. Illustration of detection of uneven coating of cleaning liquid FIG. 6 is a flowchart showing the flow of detection of uneven coating of the cleaning liquid in the wiping unit shown in FIG. The flowchart which shows the flow of the wiping method which concerns on the modification 1. The block diagram which shows schematic structure of the wiping unit which concerns on the modification 2. Explanatory drawing which shows schematic structure of the structure which acquires the temperature information which concerns on the modification 3. The block diagram which shows schematic structure of the wiping unit which concerns on 2nd Embodiment of this invention. Explanatory drawing schematically showing the connection structure between the cleaning liquid tank and the cleaning liquid spray head The block diagram which shows the structure of the control system of the inkjet recording device to which the wiping unit shown in FIG. 16 is applied. Flowchart showing the flow of cleaning liquid unevenness detection based on the speed information of the cleaning liquid Flow chart showing the flow of cleaning liquid coating unevenness detection based on consumption information per unit time of cleaning liquid

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

[First Embodiment]
(Description of overall configuration of inkjet recording apparatus)
FIG. 1 is an overall configuration diagram showing a schematic configuration of an ink jet recording apparatus (liquid ejection apparatus) to which a wiping unit (maintenance apparatus) according to a first embodiment of the present invention is applied.

  The ink jet recording apparatus 10 shown in FIG. 1 holds a recording medium (not shown in FIG. 1, not shown in FIG. A printing unit 14 including inkjet heads 14K, 14C, 14M, and 14Y that discharge color inks corresponding to K (black), C (cyan), M (magenta), and Y (yellow) to the recorded recording medium; , Including.

  The recording medium conveyance unit 12 includes an endless conveyance belt 16 having a large number of suction holes (not shown) in a recording medium holding area where a recording medium is held, and a conveyance roller (driving roller) around which the conveyance belt 16 is wound. , Driven rollers) 18 and 20 and the back side of the conveyance belt 16 in the recording medium holding region (the surface opposite to the recording medium holding surface on which the recording medium 40 is held), and the non-moving roller provided in the recording medium holding region. A negative pressure generator 22 that generates a negative pressure in the illustrated suction hole and a vacuum pump 24 connected to the negative pressure generator 22 are included.

  The carry-in unit 26 into which the recording medium is carried is provided with a pressing roller 28 for preventing the recording medium from floating, and the discharge unit 30 from which the recording medium is discharged is also provided with a pressing roller 32. .

  The recording medium carried in from the carry-in section 26 is applied with negative pressure from the suction holes provided in the recording medium holding area and is held in the recording medium holding area of the transport belt 16.

  A temperature adjustment unit 34 for adjusting the surface temperature of the recording medium to a predetermined range is provided on the upstream side of the printing unit 14 (upstream side in the recording medium conveyance direction) on the recording medium conveyance path. A reading device (reading sensor) 36 that reads an image recorded on the recording medium 40 is provided on the rear side (downstream side in the recording medium conveyance direction).

  The recording medium carried in from the carry-in section 26 is sucked and held in the recording medium holding area of the conveyor belt 16 and is subjected to temperature adjustment processing by the temperature adjustment section 34, and then image recording is performed in the printing section 14.

  The recording medium on which the image is recorded is ejected from the ejecting unit 30 after the recorded image (test pattern) is read by the reading device 36.

(Composition of printing part)
FIG. 2 is a plan view showing a schematic configuration of the printing unit 14. The printing unit 14 shown in the figure is a full-line type ink jet head in which a plurality of nozzles (not shown in FIG. 2 and indicated by reference numeral 50 in FIG. 4) are arranged over a length exceeding the entire width of the recording medium 40. 14K, 14C, 14M, and 14Y are provided.

  In the figure, a double-headed arrow line with a symbol M represents the width direction (main scanning direction) of the recording medium 40.

  The inkjet heads 14K, 14C, 14M, and 14Y are arranged in this order from the upstream side in the conveyance direction (sub-scanning direction) S of the recording medium 40. A recorded image can be recorded over the entire area of the recording medium 40 by a single-pass method in which the full-line inkjet heads 14K, 14C, 14M, and 14Y and the recording medium 40 are moved only once relatively.

  The printing unit 14 is not limited to the above-described form. For example, the inkjet head 14 corresponding to LC (light cyan) or LM (light magenta) may be provided. Further, the arrangement order of the inkjet heads 14K, 14C, 14M, and 14Y can be changed as appropriate.

(Inkjet head structure)
Next, an example of the structure of the inkjet heads 14K, 14C, 14M, and 14Y provided in the printing unit 14 will be described. Since the structures of the inkjet heads 14K, 14C, 14M, and 14Y corresponding to the respective colors are common, hereinafter, the inkjet head is denoted by reference numeral 41 as a representative thereof.

  FIG. 3 is a schematic configuration diagram of the ink jet head 41, which is a diagram (a plan perspective view of the ink jet head) of the recording surface of the recording medium viewed from the ink jet head 41. The ink jet head 41 shown in the figure forms a multi-head by connecting n head modules 42-i (i is an integer from 1 to n) in a line along the longitudinal direction of the ink jet head 41.

  Each head module 42-i is supported by head covers 44 and 46 from both sides of the inkjet head 41 in the short direction. Although illustration is omitted, it is also possible to configure a multi-head by arranging the head modules 42 in a staggered manner.

  The head module 42-i constituting the inkjet head 41 has a substantially parallelogram-shaped planar shape, and an overlap portion is provided between adjacent head modules. The overlap portion is a connecting portion of the head modules, and is formed by nozzles in which adjacent dots belong to different head modules in the arrangement direction of the head modules 42-i.

  FIG. 4 is an explanatory diagram of the nozzle arrangement of the head module 42-i. As shown in the figure, each head module 42-i has a structure in which nozzles 50 are two-dimensionally arranged, and a head provided with such a head module 42-i is a so-called matrix head. .

  The head module 42-i shown in FIG. 4 has a large number of nozzles 50 along a column direction W that forms an angle α with respect to the sub-scanning direction S and a row direction V that forms an angle β with respect to the main scanning direction M. It has an aligned structure, and the substantial nozzle arrangement density in the main scanning direction M is increased.

  In FIG. 4, the nozzle group (nozzle row) arranged along the row direction V is denoted by reference numeral 52, and the nozzle group (nozzle row) arranged along the column direction W is denoted by reference numeral 54. ing.

  In addition, as another example of the matrix arrangement of the nozzles 50, a configuration in which a plurality of nozzles 50 are arranged along the row direction along the main scanning direction M and the column direction oblique to the main scanning direction M can be given.

  In this example, an example in which a full-line type recording head is provided is illustrated. However, a short inkjet head is scanned in the width direction on the recording medium 40 to perform image recording in the same direction, and one time in the same direction. When the image recording is completed, the recording medium 40 is moved by a predetermined amount in a direction orthogonal to the scanning direction of the inkjet head, and the operation of performing the image recording while scanning the inkjet head for the next area is repeated, and the recording medium 40 is repeated. It is also possible to apply a serial system that records images over the entire area.

  FIG. 5 is a cross-sectional view showing a three-dimensional structure of the inkjet head 41 (head module 42), and illustrates a droplet discharge element for one channel. As shown in the figure, the inkjet head 41 of this example includes a nozzle plate 51 in which openings of a plurality of nozzles 50 are formed, a flow path plate in which flow paths such as a pressure chamber 52 and a common flow path 53 are formed, and the like. It consists of the structure which laminated and joined.

  The nozzle plate 51 constitutes a nozzle surface (liquid ejection surface) 51 </ b> A of the inkjet head 41, and a plurality of nozzles 50 communicating with the pressure chambers 52 are formed.

  The flow path plate forms a side wall portion of the pressure chamber 52 and forms a flow path that forms a supply port 54 as a narrowed portion (most narrowed portion) of an individual supply path that guides ink from the common flow path 53 to the pressure chamber 52. It is a member.

  For convenience of explanation, the flow path plate has a structure in which one or a plurality of substrates are stacked, although it is illustrated schematically in FIG. The nozzle plate 51 and the flow path plate can be processed into a required shape by a semiconductor manufacturing process (thin film forming process) using silicon as a material.

  The common flow path 53 communicates with an ink tank (not shown) that is an ink supply source, and ink supplied from the ink tank is supplied to each pressure chamber 52 via the common flow path 53.

  The diaphragm 55 that constitutes a part of the pressure chamber 52 (the top surface in FIG. 5) includes an upper (individual) electrode 56A and a lower (common) electrode 56B, and includes an upper electrode 56A and a lower electrode 56B. A piezoelectric element 56 having a structure in which a piezoelectric body 56C is sandwiched therebetween is joined.

  When the diaphragm 55 is made of a metal thin film or a metal oxide film, it functions as a common electrode corresponding to the lower electrode 56B of the piezoelectric element 56. 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 upper electrode 56A, the piezoelectric element 56 is deformed to change the volume of the pressure chamber 52, and ink is ejected from the nozzle 50 due to the pressure change accompanying this. When the piezoelectric element 56 returns to its original state after ink ejection, new ink is refilled into the pressure chamber 52 from the common channel 53 through the supply port 54.

  The ink jet head ejection method shown in this example may be a piezoelectric method that utilizes the flexural deformation of the piezoelectric element, or a thermal method that utilizes the film boiling phenomenon of ink in the liquid chamber communicating with the nozzle. Also good.

(Description of maintenance unit)
Next, a maintenance unit (wiping unit) for removing deposits attached to the inkjet head 41 (nozzle surface 51A) will be described in detail.

  FIG. 6 is an explanatory diagram schematically showing an arrangement example of the maintenance unit 60 (wiping unit 61) in the ink jet recording apparatus shown in FIG. In addition, the direction penetrating the paper surface in the figure is the conveyance direction of the recording medium 40.

  The wiping unit 61 shown in the figure is arranged at a maintenance position where the inkjet head 41 is moved from the printing position on the conveyance path of the recording medium 40 (see FIG. 2) in the direction orthogonal to the recording medium conveyance direction (shown by the arrow line). ing.

  That is, the maintenance of the inkjet head 41 is performed in a state where the inkjet head 41 is moved from the printing position (position on the conveyance path of the recording medium 40) in a direction orthogonal to the recording medium conveyance direction, and the inkjet head 41 is moved to the maintenance position. Executed.

  The inkjet head 41 moved to the maintenance position brings the web (wiping member) 62 into contact with the nozzle surface 51A, and in this state, the web 62 is caused to travel in the short direction (sub-scanning direction) of the inkjet head 41. The nozzle surface 51 </ b> A is wiped off by 62.

  FIG. 6 shows a mode in which the wiping roller 64 (the driving roller 85 shown in FIG. 7) is pressed from the side opposite to the contact surface of the web 62 with the nozzle surface 51A to bring the web 62 into contact with the nozzle surface 51A. ing.

  The maintenance unit 60 may include a purge unit that performs processes such as purge and suction of the inkjet head in addition to the wiping unit that performs the wiping process of the nozzle surface 51A of the inkjet head 41.

  Further, as shown in FIG. 2, in the embodiment including a plurality of inkjet heads 14K, 14C, 14M, and 14Y, a maintenance unit 60 (wiping unit 61) may be provided for each inkjet head 14K, 14C, 14M, and 14Y. One or more maintenance units 60 (wiping units 61) than the number of inkjet heads 14K, 14C, 14M, and 14Y are provided, and one maintenance unit 60 (wiping unit 61) corresponds to a plurality of inkjet heads. Good.

(Description of wiping unit)
FIG. 7 is an overall configuration diagram showing a schematic configuration of the wiping unit 61. The wiping unit 61 shown in the figure includes a winding unit 65 and a wiping unit 66 that are configured separately and independently.

  As described above, the wiping unit 61 is moved in a direction substantially parallel to the short direction of the inkjet head 41 as a whole by the moving table 68 while running the web 62 with respect to the inkjet head 41 stopped at the maintenance position ( The ink-jet head 41 is wiped off by moving to an arrow line).

  For this reason, the wiping unit 61 is configured such that the web 62 is unwound from the winding unit 65 and is wound around the winding unit 65 around the wiping unit 66 for wiping operation.

  A take-up unit 65 that functions as a means for running the web 62 includes a feed reel 70 that is rotatably supported by a frame (not shown), a take-up reel 72 that is rotatably supported by a frame (not shown), A take-up motor 74 for rotating the reel 72.

  The delivery reel 70 disposed on the upper side is loaded with a roll-shaped web 62 (unused web 62). The web 62 delivered from the delivery reel 70 is sent to the wiping unit 66 via the speed detection roller 76.

  A timing belt 78 is stretched between the take-up reel 72 and the take-up motor 74, and the take-up reel 72 is rotated by the rotation of the take-up motor 74 and the web 62 is taken up. That is, the take-up reel 72 functions as a means for collecting the used web 62.

  The wiping unit 66 is also provided with a wiping motor (not shown) that sends the web 62. The delivery reel 70 is braked and rotated so as to resist the wiping motor by a torque limiter 82 attached to the rotary shaft 70A.

  The speed detection roller 76 is a grip roller composed of two freely rotating upper and lower rollers 76A and 76B, and controls the operation of the take-up motor 74 based on speed information obtained from the speed detector 84 provided thereon.

  That is, the delivery reel 70 is delivered with the web 62 stretched, and the take-up reel 72 is configured to take up the web 62 so as not to be slack.

  The wiping unit 66 is disposed so as to face the wiping roller 64 in parallel with the wiping roller 64 rotatably supported by a base frame (not shown), a wiping motor (not shown) that rotates the wiping roller 64, and the wiping roller 64. A cleaning liquid spraying head 88 is provided, and a pair of air cylinders 90 of a double action type that raises and lowers the base frame.

  The base frame and the wiping roller 64, the wiping motor and the like supported by the pair of air cylinders 90 that are driven simultaneously are configured to move up and down.

  As an example of the configuration of the wiping roller 64, a configuration including a driving roller 85 connected to a wiping motor via a timing belt (not shown) and a driven roller 86 that contacts the driving roller with the web 62 interposed therebetween is provided. Is mentioned.

  The drive roller 85 is constituted by a rubber roller in which rubber having elasticity or flexibility is wound around the core portion, and is configured to be pressed against the nozzle forming surface 67 of the inkjet head 41 while running the web 62 that circulates around the rubber roller. Can do.

  The cleaning liquid spraying head 88 is disposed in the vicinity of the upstream side of the wiping roller 64 in the web moving direction, and has a plurality of spray nozzles (not shown in FIG. 7, denoted by reference numeral 100 in FIG. 9) on the surface facing the traveling web 62. Are shown).

  A cleaning liquid composed of pure water, an ink solvent, or the like is sprayed from the spray nozzle onto the web 62 sent from the delivery reel 70. It is also possible to apply a dedicated cleaning liquid provided with a material having a cleaning function.

  The web 62 sprayed with the cleaning liquid and impregnated with the cleaning liquid is brought into contact with the nozzle surface 51 </ b> A of the inkjet head 41, and the nozzle surface 51 </ b> A is wiped off by the web 62.

  A cleaning liquid pan 92 is provided below the wiping roller 64, and is configured to receive the cleaning liquid dropped from the web 62 and the nozzle surface 51A.

The wiping unit 61 shown in this example includes a first temperature sensor 94 (S _t1 ) on the upstream side of the cleaning liquid spraying head 88 in the web feeding direction, and a second temperature sensor 96 (on the downstream side of the cleaning liquid spraying head 88 in the web feeding direction). S _t2 ).

  The temperature information of the web 62 before the cleaning liquid is sprayed is acquired by the first temperature sensor 94, and the temperature information of the web 62 after the cleaning liquid is sprayed and impregnated with the cleaning liquid is acquired by the second temperature sensor 96. Is done.

  The temperature change of the web 62 before and after the cleaning liquid spray is obtained from the temperature information of the web 62 before and after the cleaning liquid spray obtained by the first temperature sensor 94 and the second temperature sensor 96, and the moving direction of the web 62 on the web 62 is determined. The presence / absence of uneven coating of the cleaning liquid is grasped (details will be described later).

  Here, with reference to FIG. 8, the wiping operation | movement of 51 A of nozzle surfaces is demonstrated easily. When the inkjet head 41 is moved to reach a predetermined maintenance position (wiping position), the moving table 68 is driven, and the wiping unit 61 is advanced to sufficiently approach the inkjet head 41.

  When the wiping roller 64 has moved to the vicinity of the inkjet head 41, the moving table 68 is stopped, the air cylinder 90 (see FIG. 7) is driven, and the wiping roller 64 is brought into contact (pressed) with the nozzle surface 51A of the inkjet head 41. The roller 64 (only the driving roller 85 of FIG. 7 is shown and the driven roller 86 is omitted) is raised.

  8 is a state in which the wiping roller 64 (web 62) is brought into contact (pressed) with the nozzle surface 51A.

  Here, the winding motor 74 and the wiping motor are driven to run (move) the web 62 (the moving direction of the web 62 is indicated by an arrow curve), and the cleaning liquid spraying head 88 is operated to start spraying the cleaning liquid. To do.

  Simultaneously with the start of spraying of the cleaning liquid, the moving table 68 (see FIG. 7) is driven to feed the web 62, while the wiping roller 64 wipes the nozzle surface 51A of the inkjet head 41 so that the nozzle surface 51A is short. The ink jet head 41 is advanced from one end in the hand direction along the short direction of the ink jet head 41 (the direction of advance of the wiping roller 64 is indicated by an arrow line).

  8, when the wiping roller 64 reaches the other end in the short direction of the nozzle surface 51A and the wiping operation of the nozzle surface 51A is completed, the feeding of the web 62 is stopped and the wiping roller 64 is removed. , And the moving table 68 is operated to move the wiping unit 61 back to the original position.

  FIG. 9A is a diagram illustrating a schematic structure of the cleaning liquid spray head 88 and a schematic structure of the first temperature sensor 94 (second temperature sensor 96). FIG. 9B is an explanatory diagram showing the relationship between the spray region of the cleaning liquid spray head 88 and the temperature measurement region of the first temperature sensor 94 (second temperature sensor 96).

  Since the first temperature sensor 94 and the second temperature sensor 96 can have the same configuration, only the first temperature sensor 94 will be described here. Further, the direction penetrating the paper surface in FIGS. 9A and 9B is the feeding direction of the web 62.

  The cleaning liquid spray head 88 shown in FIG. 9A is provided with a plurality of spray nozzles 100 over a length exceeding the width of the web 62 (see FIG. 9B) (the length in the direction orthogonal to the feed direction). ing. FIG. 9A illustrates a form in which a plurality of spray nozzles 100 are arranged at equal intervals.

  Although detailed illustration is omitted, the cleaning liquid spraying head 88 shown in FIG. 9A has a tube connected to a cleaning liquid tank (not shown) connected to the opposite side of the surface on which the spray nozzle 100 is disposed. A plurality of joints are provided (see FIG. 17).

  The structure of the cleaning liquid spray head 88 such as the number of spray nozzles 100 and the arrangement interval of the spray nozzles 100 is determined according to the structure of the ink jet head 41. For example, a mode in which one (or two or more) spray nozzles 100 are provided for each head module 42 with respect to the inkjet head 41 in which a plurality of head modules 42 as illustrated in FIG.

  Further, the opening shape of the spray nozzle 100 is not limited to a circular shape, and various shapes such as an ellipse, an ellipse, and a quadrangle can be applied depending on the spray range, the spray amount, and the like.

As shown in FIG. 9B, the mist-like cleaning liquid sprayed from each spray nozzle 100 spreads concentrically around the spray nozzle 100. The spray region for each spray nozzle 100 (the length of the spray region in the width direction of the web 62 is L ₂ ) may be slightly overlapped or not overlapped as shown (adjacent spray nozzles). The spray 62 may be spread out in the web 62 while being impregnated with a cleaning liquid.

A first temperature sensor 94 (second temperature sensor 96) shown in FIG. 9A has a structure in which a plurality of detection elements 94 A are arranged along the width method of the web 62. In the example shown in FIG. 9A, the detection width (L ₁ ) of one detection element 94A corresponds to the spray region width (L ₂ ) of one spray nozzle 100 shown in FIG. 9B. .

That is, in the forms shown in FIGS. 9A and 9B, there is a relationship of (detection width L ₁ of one detection element 94A) = (width L ₂ of the spray region of one spray nozzle 100). .

  A non-contact type temperature sensor such as an infrared radiation thermometer is applied to the detection element 94A. In this example, a configuration in which a plurality of detection elements 94A are arranged along the width direction of the web 62 is shown, but a configuration in which the detection elements 94A are scanned along the width direction of the web 62 is also possible.

  9A illustrates the first temperature sensor 94 (second temperature sensor 96) including one detection element 94A for one spray nozzle 100, the number of detection elements 94A is as follows. It is determined appropriately according to the temperature detection range of the detection element 94A.

  In order to improve the accuracy of temperature detection, a mode in which the temperature of the cleaning liquid sprayed from the cleaning liquid spray head 88 is adjusted to be equal to or higher than the environmental temperature is preferable. For example, a mode in which a temperature controller is built in the cleaning liquid spray head 88 and a mode in which a temperature controller is provided in a supply path for supplying the cleaning liquid to the cleaning liquid spray head 88 can be given. Such a temperature regulator is illustrated in FIG.

  The temperature of the cleaning liquid sprayed from the cleaning liquid spray head 88 is more preferably 60 ° C. or more (twice or more of the environmental temperature). If the temperature of the cleaning liquid is too high, drying of the web 62 due to evaporation of the cleaning liquid is promoted, or the temperature of the cleaning liquid is transmitted to the ink jet head 41 so that the inside of the ink jet head 41 (particularly, near the opening of the nozzle 50). Since there is a concern that the ink will solidify, the temperature of the cleaning liquid is preferably 80 ° C. or lower.

(Description of control system)
FIG. 10 is a block diagram illustrating a schematic configuration of a control system of the inkjet recording apparatus 10. The control system shown in the figure includes a communication interface 150, a system controller 152, a memory 154, a maintenance processing control unit 156, a droplet ejection control unit 158, a buffer memory 160, a program storage unit 162, and the like.

  The communication interface 150 is an interface unit that receives digital-format print data sent from the host computer 164. As the communication interface 150, a serial interface or a parallel interface may be applied. In this part, a buffer memory (not shown) for speeding up communication may be mounted.

  The system controller 152 is a control unit that controls the communication interface 150, the memory 154, the maintenance processing control unit 156, the droplet ejection control unit 158, and the like. The system controller 152 includes a central processing unit (CPU) and its peripheral circuits, and performs communication control with the host computer 164, read / write control of the memory 154, and the motor of the head transport unit 165 and web transport. A control signal for controlling the motor of the unit 166 (winding motor 74, wiping motor, etc.) and the temperature regulator 168 for adjusting the temperature of the cleaning liquid is generated.

  The memory 154 is storage means used as a temporary storage area for data and a work area when the system controller 152 performs various calculations. Print data input via the communication interface 150 is temporarily stored in the memory 154.

  The memory 154 also functions as a storage unit that stores various information and various parameters. A form having a user interface capable of inputting various information by an operator is preferable. As the memory 154, a magnetic medium such as a hard disk can be used in addition to a memory made of a semiconductor element.

  The maintenance process control unit 156 is a block that performs overall control of the maintenance unit 60 including the wiping unit 61 illustrated in FIG. 7. Based on various control information acquired via the system controller 152 and various detection information acquired from the first temperature sensor 94, the second temperature sensor 96, and the like, a command signal is sent to each part of the maintenance unit.

  For example, when the maintenance mode of the inkjet head 41 is selected, a command signal for moving the inkjet head 41 to the head transport unit 165 and a command signal for sending the web 62 to the web transport unit 166 are sent. Is sent out.

  Further, based on the temperature information obtained from the first temperature sensor 94 and the second temperature sensor 96, the presence or absence of uneven coating of the cleaning liquid on the web 62 is grasped. When it is determined that the coating unevenness exceeding the allowable range has occurred, a signal for notifying the notification unit 170 is transmitted via the system controller 152.

  Examples of notification by the notification unit 170 include a form in which sound and alarm sound are generated, and a form in which character information is displayed on the display device.

  The droplet ejection control unit 158 has a signal processing function for performing various processes such as various processes and corrections for generating a signal for controlling the ejection of the inkjet head 41 from the print data in the memory 154 according to the control of the system controller 152. It is a control unit that supplies the generated ejection control signal to the head driver 172.

  Necessary signal processing is performed in the droplet ejection control unit 158, and the ejection amount, ejection position, and ejection timing of the inkjet head 41 of the ink ejected from the inkjet head 41 via the head driver 172 based on the ejection (application) data. Is controlled. As a result, a desired color image is formed on the recording medium.

  The droplet ejection controller 158 is provided with a buffer memory 160, and print data, parameters, and other data used when print data is processed in the droplet ejection controller 158 are temporarily stored in the buffer memory 160.

  In FIG. 10, the buffer memory 160 is shown in a mode associated with the droplet ejection control unit 158, but it can also be used as the memory 154. Further, a mode in which the droplet ejection control unit 158 and the system controller 152 are integrated and configured by one processor is also possible.

  The head driver 172 generates a drive signal for driving the piezoelectric element 38 (see FIG. 5) of the ink jet head 41 based on the ejection data given from the droplet ejection control unit 158, and the generated drive signal is output to the piezoelectric element 38. Supply. The head driver 172 may include a feedback control system for keeping the driving conditions of the inkjet head 41 constant.

[Explanation of cleaning liquid unevenness detection]
Next, detection of uneven coating of the cleaning liquid on the web 62 based on the temperature information obtained from the first temperature sensor 94 and the second temperature sensor 96 will be described in detail.

  FIG. 11 is an explanatory diagram of detection of uneven coating of the cleaning liquid. As shown in FIG. 11A, it is assumed that the cleaning liquid is not ejected from a certain spray nozzle (in the illustrated example, the spray nozzle at the substantially central portion of the cleaning liquid spray head 88).

  The web 62 changes between a dry temperature (drying temperature) and a temperature impregnated with the cleaning liquid (wetting temperature). When the temperature adjustment processing is not performed on the web 62 itself, it is considered that the drying temperature is substantially the same as the environmental temperature, and the wet temperature is substantially the same as the temperature of the cleaning liquid.

  Then, the temperature information of the dry state of the web 62 is acquired by the first temperature sensor 94 (see FIG. 7), the temperature information of the state in which the cleaning liquid of the web 62 is impregnated by the second temperature sensor 96 is acquired, and these Calculate the differential temperature.

  If no unevenness of the cleaning liquid is generated on the web 62, the difference temperature between the drying temperature and the wetting temperature is a constant value as shown by the broken line 200 in FIG. It will be.

  On the other hand, when unevenness of the cleaning liquid is generated on the web 62, the difference temperature between the drying temperature and the wet temperature does not become a constant value, but varies depending on the position of the web 62.

  As shown in FIG. 11A, if the cleaning liquid is not sprayed from the spray nozzle 100 at the center of the cleaning liquid spray head 88, the first temperature sensor 94 and the second temperature sensor 96 both acquire the drying temperature. As indicated by the solid line indicated by the reference numeral 202 in FIG. 11B, the differential temperature at a specific position on the web 62 varies greatly with respect to the differential temperature at other positions.

  The example shown in FIG. 11B is when the wetting temperature> the drying temperature (when the temperature of the cleaning liquid is adjusted to the ambient temperature or higher), and the differential temperature = (wetting temperature) − (drying temperature).

  Therefore, when the difference between the temperature information obtained from the first temperature sensor 94 and the temperature information obtained from the second temperature sensor 96 is obtained, and the amount of variation for each position of the web 62 is larger than a predetermined amount. Therefore, it is determined that the unevenness of the cleaning liquid has occurred.

  FIG. 12 is a flowchart showing a flow of control for detecting the coating liquid unevenness described above. When the coating unevenness detection is started (step S10), the drying temperature is acquired by the first temperature sensor 94 (step S12), and the wetting temperature is acquired by the second temperature sensor 96 (step S14).

  Next, a difference temperature expressed as a difference between the drying temperature and the wetting temperature is calculated (step S16), and the difference temperature is compared with a preset threshold value (step S18).

  In step S18, when the differential temperature exceeds the threshold value (No determination), the process returns to step S12, and the acquisition of the temperature information of the web 62 is continued.

  On the other hand, if the difference temperature is equal to or lower than the threshold value in step S18 (Yes determination), the notification unit 170 (see FIG. 10) notifies that fact (step S20), and detects uneven coating in one sampling. Is terminated (step S22).

  12 is started before the web 62 is brought into contact with the nozzle surface 51A (the state shown in FIG. 7), and it is confirmed that there is no unevenness in the cleaning liquid on the web 62. Then, the web 62 is brought into contact with the nozzle surface 51A.

  In addition, the detection of uneven coating of the cleaning liquid is repeatedly performed at a predetermined sampling timing within a period during which the maintenance process (wiping process) of the inkjet head 41 is performed.

  According to the wiping unit (maintenance unit) configured as described above, since the unevenness of the cleaning liquid in the moving direction of the web 62 is detected based on the temperature information of the web 62, the unevenness of the cleaning liquid on the web 62 is surely ensured. To be grasped.

  Accordingly, it is possible to prevent the wiping process of the nozzle surface 51A by the web 62 from being dry wiping. Further, by detecting the temperature of the entire width of the web 62, it is possible to grasp the uneven coating of the cleaning liquid in the width direction of the web 62 as well.

  By adjusting the cleaning liquid sprayed from the cleaning liquid spray head 88 to a temperature exceeding the environmental temperature (that is, the drying temperature of the web 62), the difference temperature obtained by subtracting the drying temperature from the wet temperature is made larger. Therefore, it is possible to improve the accuracy of detection of uneven coating of the cleaning liquid.

[Modification]
Next, a modified example of the above-described detection of uneven coating of the cleaning liquid will be described.

(Modification 1)
In the first modification, the first temperature sensor 94 is omitted, and a mode in which the drying temperature of the web 62 is stored in advance will be described.

  FIG. 13 is a flowchart showing a flow of nonuniform coating detection according to the first modification. The flowchart shown in FIG. 12 omits the drying temperature acquisition step (step S12) of the flowchart shown in FIG. 12, and inputs the drying temperature information from the user interface or the like (step S11), and the step of storing the drying temperature. (Step S13) is included.

  Such a drying temperature may be an environmental temperature or a value measured when the apparatus is in operation. Moreover, it is good also as a fixed value for every apparatus.

  According to the first modification, the first temperature sensor 94 can be omitted, so that the device configuration can be simplified. In addition, since the parameter for obtaining the difference temperature can be a fixed value, the control load for obtaining temperature information and the computation load for obtaining the difference temperature are reduced.

(Modification 2)
FIG. 14 is a configuration diagram illustrating a schematic configuration of a wiping unit according to the second modification. In the wiping unit 61 ′ shown in the figure, a second temperature sensor 96 ′ is built in the wiping roller 64 (drive roller 85).

  Further, the second temperature sensor 96 ′ is a contact type thermometer that measures the temperature of the web 62 by contacting the web 62 and acquires temperature information of the web 62. An example of a contact thermometer is a contact thermometer provided with a thermocouple.

  Of course, a form in which a contact-type thermometer is applied to the first temperature sensor 94 is also possible, and a form in which the first temperature sensor 94 is omitted as in Modification 1 is also possible.

  According to the second modification, the contact-type thermometer is applied when acquiring the temperature information of the web 62, thereby preventing the occurrence of variations in temperature measurement due to environmental changes. Further, by incorporating a thermometer in the wiping roller 64, temperature information of the web 62 at a position closer to the nozzle surface 51A can be acquired.

  In the example illustrated in FIG. 14, the driving roller 85 includes the second temperature sensor 96 ′, but the driven roller 86 may include the second temperature sensor 96 ′.

(Modification 3)
FIG. 15 is an explanatory diagram illustrating a schematic configuration of a configuration for acquiring web 62 temperature information according to the third modification. In the configuration for acquiring the temperature information of the web 62 shown in the figure, an image pickup apparatus 95 including image pickup elements 95A and 95A and a magnifying optical system 95B is provided instead of the first temperature sensor 94 and the second temperature sensor 96. .

  FIG. 15A is a plan view illustrating a configuration example of the imaging device 95, in which the imaging device 95 is illustrated by a solid line, and the cleaning liquid spray head 88 is illustrated by a broken line. FIG. 15B is an explanatory diagram illustrating the imaging region enlarged by the magnifying optical system of the imaging device 95.

  The imaging device 95 shown in FIG. 15A has an imageable area smaller than the imaging target area (temperature measurement range). The imaging area is enlarged using the magnifying optical system 95B, and corresponds to the imaging target area. ing.

  Of course, a configuration in which the imaging element 95A is configured to scan in the width direction of the web 62 and the magnifying optical system 95B is omitted is also possible.

  A line sensor in which CCDs are arranged in a row or an area sensor in which CCDs are arranged two-dimensionally can be applied to the image sensor 95A.

  The imaging signal acquired by the imaging device 95 is subjected to predetermined signal processing by a signal processing unit (not shown), and a captured image of the web is generated. Such captured images are displayed on a display device (not shown) such as an LDC display.

  The signal processing unit (not shown) may have a form associated with the system controller 152 and the maintenance processing control unit 156 in FIG. Further, the display device may have a form as a function of the notification unit 170 in FIG. In addition, the form provided with the illuminating device which illuminates the imaging region of the imaging device 95 (imaging element 95A) is preferable.

  According to the third modification, since the unevenness of the cleaning liquid on the web 62 can be recognized as an image, the cleaning liquid can be used even when it is difficult to detect the unevenness of the cleaning liquid due to a temperature difference, such as when the temperature of the cleaning liquid is close to normal temperature. The coating unevenness can be detected, and when the foreign matter exists on the web 62 before wiping, the foreign matter can be detected.

[Second Embodiment]
Next, a wiping unit according to the second embodiment of the present invention will be described. FIG. 16 is an overall configuration diagram of a wiping unit 261 according to the second embodiment. 16 that are the same as or similar to those in FIG. 7 are assigned the same reference numerals, and descriptions thereof are omitted.

The wiping unit 261 (wiping unit 266) shown in the figure is supplied to the cleaning liquid spray head 88 instead of the first temperature sensor 94 and the second temperature sensor 96 of the wiping unit 61 (wiping unit 66) shown in FIG. A flow rate measuring device (S _v ) 294 for measuring the flow rate of the cleaning liquid is provided.

  That is, the cleaning liquid spray head 88 communicates with the cleaning liquid tank 291 via the cleaning liquid tube 289, and the flow rate information of the cleaning liquid supplied to the cleaning liquid spray head 88 acquired from the flow rate measuring device 294 attached to the cleaning liquid tube 289. Based on the above, the uneven coating of the cleaning liquid is grasped indirectly.

  The flow rate of the cleaning liquid passing through the cleaning liquid tube 289 is proportional to the amount of the cleaning liquid ejected from the cleaning liquid spraying head 88, and when the flow rate of the cleaning liquid passing through the cleaning liquid tube 289 exceeds the upper limit value of the predetermined range (if fast) It is considered that excessive spraying of cleaning liquid has occurred.

  On the other hand, when the flow rate of the cleaning liquid passing through the cleaning liquid tube 289 is less than the lower limit of the predetermined range (when it is slow), it is considered that the cleaning liquid is insufficiently jetted.

  Further, the cleaning liquid tank 291 is provided with a liquid amount measuring device 296 that measures the amount of the cleaning liquid stored therein. As an example of the liquid amount measuring device 296, there is a water level sensor that detects the water level (level of liquid level) of the cleaning liquid in the cleaning liquid tank 291.

  If the consumption of cleaning liquid per unit time is detected and the consumption of cleaning liquid exceeds the upper limit of the predetermined range, it is considered that excessive ejection of the cleaning liquid has occurred, and the consumption of cleaning liquid is the lower limit of the predetermined range. If it is less than that, it is considered that the cleaning liquid is insufficiently jetted.

  FIG. 17 is an explanatory diagram schematically showing a connection structure between the cleaning liquid tank 291 and the cleaning liquid spraying head 88. The cleaning liquid spray head 88 shown in the figure has a structure in which a flow path or the like is partitioned for each spray nozzle 100, and a joint 293 is provided for each section, and a cleaning liquid tube 289 is connected to each joint 293. The

  According to the configuration shown in FIG. 17, the flow rate of the cleaning liquid is detected for each spray nozzle 100, and the uneven coating of the cleaning liquid on the web 62 can be detected for each spray nozzle 100.

  FIG. 18 is a block diagram illustrating a schematic configuration of a control system of the ink jet recording apparatus including the wiping unit 261 according to the second embodiment. In FIG. 18, parts that are the same as or similar to those in FIG. 10 are given the same reference numerals, and descriptions thereof are omitted.

  The control system shown in FIG. 18 includes a flow rate measuring device 294 and a liquid amount measuring device 296 instead of the first temperature sensor 94 and the second temperature sensor 96 shown in FIG. The measurement signal representing the flow rate information acquired from the flow rate measuring device 294 and the measurement signal representing the flow rate information acquired from the liquid amount measuring device 296 are sent to the system controller 152.

  The system controller 152 sends the measurement signal to the maintenance processing control unit 156, and the maintenance processing control unit 156 determines whether there is an abnormality in the flow rate of the cleaning liquid and whether there is an abnormality in the consumption amount of the cleaning liquid.

  If it is determined that an abnormality has occurred in the flow rate or consumption of the cleaning liquid, the fact is sent to the notification unit 170 via the system controller 152, and the notification unit 170 notifies the abnormality. When at least one of an abnormality in the flow rate of the cleaning liquid and an abnormality in the consumption amount of the cleaning liquid has occurred, a notification that there is an abnormality is given.

  FIG. 19 is a flowchart showing a flow of detection of uneven coating of cleaning liquid based on flow rate information of the cleaning liquid. When the detection of uneven coating of the cleaning liquid is started (step S100), flow rate information of the cleaning liquid is acquired (step S102), and it is determined whether or not the flow rate of the cleaning liquid is in a normal range (step S104).

  In step S104, when the flow rate of the cleaning liquid is in the normal range (Yes determination), the process returns to step S102, and acquisition of the flow rate information of the cleaning liquid is continued. On the other hand, if the flow rate of the cleaning liquid is out of the normal range in step S104 (No determination), the fact that the cleaning liquid is abnormal (unevenness in the cleaning liquid has occurred) is notified (step S106), and sampling is performed once. The coating unevenness detection is terminated (step S108).

  Note that the flow rate information of the cleaning liquid is acquired based on a predetermined sampling timing within a period during which the maintenance process of the inkjet head 41 is being performed.

  FIG. 20 is a flowchart showing a flow of detection of uneven coating of the cleaning liquid based on consumption information of the cleaning liquid per unit time. In the flowchart shown in FIG. 20, a process (step S103) of acquiring consumption information per unit time of the cleaning liquid is provided instead of the process of acquiring the flow rate information of the cleaning liquid (step S102) of the flowchart shown in FIG.

  Further, in place of the step of determining whether or not the flow rate of the cleaning liquid is in the normal range (step S104) in FIG. 19, a step of determining whether or not the amount of consumption of the cleaning liquid is in the normal range (step S105) is provided.

  It is also possible to detect uneven coating of the cleaning liquid on the web 62 by using the flow rate information of the cleaning liquid and the consumption information of the cleaning liquid in combination.

  According to the wiping unit according to the second embodiment described above, the flow rate of the cleaning liquid supplied to the cleaning liquid spray head 88 or the consumption amount of the cleaning liquid per unit time in the cleaning liquid spray head 88 is measured, and the flow rate of the cleaning liquid, Since the unevenness of the cleaning liquid on the web 62 is detected based on the consumption amount of the cleaning liquid per unit time, dry wiping is prevented when the nozzle surface 51A is wiped by the web 62.

  In addition, since a highly accurate measurement method such as the flow rate and consumption of the cleaning liquid can be used, the wet (dry) state of the web 62 can be grasped more reliably.

  Note that the first embodiment and the second embodiment of the present invention can be modified as appropriate without departing from the spirit of the present invention. For example, the present invention can be applied to a liquid discharge apparatus for industrial use in which a functional liquid (resist, light emitting functional material, etc.) is disposed on a substrate by an ink jet method.

<Appendix>
As can be understood from the description of the embodiment described in detail above, the present specification includes disclosure of various technical ideas including the invention described below.

  (Invention 1): A sheet-like wiping member that contacts the liquid ejection surface of the inkjet head to wipe the liquid ejection surface, a moving means that moves the wiping member relative to the liquid ejection surface, and the moving means Cleaning liquid spraying means for spraying the cleaning liquid onto the wiping member which is disposed upstream of the contact position between the liquid ejection surface and the wiping member in the movement path of the wiping member A wiping unit comprising: detecting means for detecting at least unevenness of the cleaning liquid in the moving direction of the moving means in the wiping member sprayed with the cleaning liquid by the cleaning liquid spraying means.

  According to the present invention, the wet state of the wiping member due to the cleaning liquid can be grasped by detecting at least the unevenness of the cleaning liquid in the moving direction of the moving means in the wiping member brought into contact with the nozzle surface of the inkjet head. .

  A form provided with an informing means for informing a detection result in the detecting means is preferable.

  The “sheet-like wiping member” includes a long continuous web. Moreover, the form which moves a wiping member includes the form which sends out a web from the roll by which the long web was wound, winds a used web around a roller, and collect | recovers.

  (Invention 2): In the wiping unit according to Invention 1, the detection means detects a temperature change of the wiping member.

  According to this aspect, it becomes possible to grasp the unevenness of the cleaning liquid on the wiping member based on the temperature change of the wiping member.

  (Invention 3): In the wiping unit according to Invention 2, the detection means includes a non-contact temperature sensor that measures the temperature of the wiping member in a non-contact manner.

  As an example of the non-contact type temperature sensor in such an embodiment, an infrared irradiation type temperature sensor can be given.

  (Invention 4): In the wiping unit according to Invention 2, the detection means includes a contact-type temperature sensor that contacts the wiping member and measures the temperature of the wiping member.

  When an example of the contact-type temperature sensor in this aspect is given, a temperature sensor provided with a thermocouple as the detection element may be mentioned.

  (Invention 5): In the wiping unit according to Invention 4, the wiping member is pressed from the side opposite to the surface to be brought into contact with the liquid ejection surface of the wiping member, and the wiping member is brought into contact with the liquid ejection surface. The contact-type temperature sensor is built in the pressing member.

  According to this aspect, it is possible to detect the temperature of the wiping member in contact with the liquid ejection surface, which contributes to downsizing of the apparatus.

  (Invention 6): The wiping unit according to any one of Inventions 1 to 5, further comprising temperature adjusting means for adjusting the temperature of the cleaning liquid so that the temperature of the cleaning liquid sprayed from the cleaning liquid spraying means is equal to or higher than the environmental temperature. It is characterized by that.

  According to this aspect, the temperature detection accuracy can be improved.

  The aspect which makes the temperature of the washing | cleaning liquid in this aspect 60 degreeC or more and 80 degrees C or less is preferable.

  (Invention 7): In the wiping unit according to Invention 1, the detection unit includes an imaging device that images the wiping member, performs predetermined image processing on an imaging signal obtained from the imaging device, and An image generating means for generating an image of unevenness of the cleaning liquid on the wiping member is provided.

  According to this aspect, even when it is difficult to detect unevenness of the cleaning liquid due to a temperature difference, such as when the temperature of the cleaning liquid is close to normal temperature, the unevenness of the cleaning liquid can be detected, and further, on the wiping member before wiping. When a foreign object exists, the foreign object can be found.

  In such an aspect, there may be a form in which the image pickup unit includes an image pickup element and a magnifying optical system that enlarges the image pickup region of the image pickup element.

  (Invention 8): In the wiping unit according to any one of Inventions 1 to 7, the detection unit includes a plurality of detection units arranged along a width direction orthogonal to a moving direction of the wiping member. It is characterized by that.

  According to this aspect, it is possible to detect unevenness of the cleaning liquid in the width direction of the wiping member. In such an aspect, an aspect in which the unevenness of the cleaning liquid is detected over a length corresponding to the entire width of the wiping member is preferable.

  (Invention 9): In the wiping unit according to any one of Inventions 1 to 8, the detection means includes a first detection unit that detects a state of the wiping member before the cleaning liquid is sprayed, and the cleaning liquid is sprayed. Cleaning liquid in the wiping member based on the relative difference between the detection result of the second detection unit that detects the state of the wiping member after being performed, and the detection result of the first detection unit and the detection result of the second detection unit It is characterized by detecting the unevenness of coating.

  In such an embodiment, it is possible to obtain a difference between an index that represents the dry state of the wiping member before the cleaning liquid is sprayed and an index that represents the wet state of the wiping member after the cleaning liquid is sprayed.

  (Invention 10): In the wiping unit according to any one of Inventions 1 to 8, the detection means includes a storage means for storing information on a state of the wiping member before the cleaning liquid is sprayed, and a cleaning liquid. A detection unit that detects a state of the wiping member after being sprayed, and a state of the wiping member before the cleaning liquid stored in the storage unit is sprayed and a detection result by the detection unit Based on the relative difference, the unevenness of the cleaning liquid in the wiping member is detected.

  According to this aspect, the cleaning liquid is sprayed in a mode in which the unevenness of the cleaning liquid is determined based on the difference between the state of the wiping member before the cleaning liquid is sprayed and the state of the wiping member after the cleaning liquid is sprayed. A detection unit for actually measuring the state of the previous wiping member can be omitted.

  (Invention 11): In the wiping unit according to Invention 1, a cleaning liquid storage means for storing the cleaning liquid supplied to the cleaning liquid spraying means, a cleaning liquid flow path for communicating the cleaning liquid storage means and the cleaning liquid spraying means, The detection means includes a flow rate sensor for detecting a flow rate of the cleaning liquid in the cleaning liquid flow path.

  According to this aspect, it is possible to indirectly grasp the unevenness of the cleaning liquid on the wiping member based on the consumption amount of the cleaning liquid per unit time.

  (Invention 12): In the wiping unit according to Invention 11, the cleaning liquid spraying unit has a structure in which a plurality of spraying units are connected in the width direction of the wiping member, and the cleaning liquid storage unit is provided for each spraying unit. And a flow rate sensor is provided in each of the cleaning liquid flow paths for each of the spray units.

  According to this aspect, it is possible to determine the unevenness of the cleaning liquid for each spray unit constituting the cleaning liquid spraying means.

  (Invention 13): The wiping unit according to Invention 1, further comprising cleaning liquid storage means for storing the cleaning liquid supplied to the cleaning liquid spraying means, wherein the detection means detects a cleaning liquid consumption amount of the cleaning liquid storage means. It includes a quantity sensor.

  According to this aspect, it is possible to indirectly grasp the unevenness of the cleaning liquid on the wiping member based on the consumption amount of the cleaning liquid per unit time.

  (Invention 14): The wiping unit according to Invention 13, further comprising cleaning liquid storage means for storing the cleaning liquid supplied to the cleaning liquid spraying means, wherein the detection means is a liquid level height of the cleaning liquid in the cleaning liquid storage means. It includes a liquid level sensor for detecting

  According to this aspect, the consumption amount of the cleaning liquid per unit time can be grasped according to the liquid level height of the cleaning liquid in the cleaning liquid storage means.

  (Invention 15): In the wiping unit according to any one of Inventions 1 to 14, the moving means includes a feeding roller around which the wiping member is wound, and the wiping member fed from the feeding roller as the liquid. At the contact position to be brought into contact with the discharge surface, a support roller that supports the wiping member from a side surface opposite to the surface to be brought into contact with the liquid discharge surface of the wiping member, and is fed from the feed roller and contacts the liquid discharge surface A take-up roll for taking up the wiped member, a motor for rotating either the feed roller or the take-up roller, and rotating the motor at a predetermined rotational speed to move the wiping member at a predetermined speed. And a motor control means for controlling the motor so as to run the vehicle.

  According to this aspect, it is possible to always use an unused wiping member by running the wiping member, and prevent the deposits removed from the liquid ejection surface by the wiping member from reattaching to the liquid ejection surface. Yes.

  (Invention 16): A sheet-like wiping member that contacts the liquid ejection surface of the inkjet head to wipe the liquid ejection surface, a moving means that moves the wiping member, and a movement path of the wiping member in the moving means A cleaning liquid spraying means for spraying a cleaning liquid on a wiping member which is disposed upstream of a contact position between the liquid discharge surface and the wiping member and moved by the moving means; and a cleaning liquid by the cleaning liquid spraying means A maintenance device comprising: a wiping unit that includes at least a detection unit that detects an uneven coating of the cleaning liquid in a moving direction of the moving unit in the wiping member sprayed with a mist.

  (Invention 17): An inkjet head having a liquid ejection surface provided with a nozzle for ejecting liquid, and a wiping unit that performs a wiping process on the liquid ejection surface of the inkjet head, wherein the wiping unit includes: A sheet-like wiping member that wipes the liquid ejection surface in contact with the liquid ejection surface of the inkjet head, a moving unit that moves the wiping member, and the liquid ejection surface of the movement path of the wiping member in the moving unit The cleaning liquid spraying means sprays the cleaning liquid onto the wiping member which is disposed on the upstream side of the contact position with the wiping member and is moved by the moving means, and the wiping in which the cleaning liquid is sprayed by the cleaning liquid spraying means Detecting means for detecting at least uneven coating of the cleaning liquid in the moving direction of the moving means in the member. A liquid discharge apparatus characterized by.

  In the inventions 16 and 17, a mode in which the wiping unit according to any one of the inventions 2 to 15 is provided is preferable.

  (Invention 18): A moving step of moving a sheet-like wiping member that is brought into contact with the liquid discharge surface of the inkjet head to wipe the liquid discharge surface; and the liquid discharge surface of the movement path of the wiping member in the moving step; At least upstream of the contact position with the wiping member, a cleaning liquid spraying step for spraying the cleaning liquid onto the wiping member moved by the moving means, and at least a wiping member sprayed with the cleaning liquid by the cleaning liquid spraying step, A wiping method comprising: a detecting step of detecting uneven coating of the cleaning liquid in the moving direction of the moving step.

  In the present invention, an aspect including a step corresponding to each means of the wiping unit according to any one of the above inventions 2 to 15 is preferable.

  DESCRIPTION OF SYMBOLS 10 ... Inkjet recording device, 14K, 14C, 14M, 14Y, 41 ... Inkjet head, 51A ... Nozzle surface, 60 ... Maintenance unit, 61 ... Wiping unit, 62 ... Web, 64 ... Wiping roller, 70 ... Delivery reel, 72 ... Take-up reel, 74 ... take-up motor, 84 ... speed detector, 88 ... cleaning liquid spray head, 94 ... first temperature sensor, 94A ... detection element, 95 ... imaging device, 95B ... magnifying optical system, 96, 96 '... Second temperature sensor, 100 ... Spray nozzle, 152 ... System controller, 156 ... Maintenance processing control unit, 165 ... Head transport unit, 166 ... Web transport unit, 168 ... Temperature regulator 168, 289 ... Cleaning liquid tube, 291 ... Cleaning liquid tank 294 ... Flow velocity measuring device, 296 ... Liquid volume measuring device

Claims (18)

A sheet-like wiping member that contacts the liquid ejection surface of the inkjet head and wipes the liquid ejection surface;
Moving means for moving the wiping member relative to the liquid ejection surface;
A cleaning liquid that is disposed on the upstream side of the contact position between the liquid discharge surface and the wiping member in the moving path of the wiping member in the moving means, and sprays the cleaning liquid onto the wiping member that is moved by the moving means. Spraying means;
In the wiping member sprayed with the cleaning liquid by the cleaning liquid spraying means, detecting means for detecting at least unevenness of the cleaning liquid in the moving direction of the moving means;
Wiping unit characterized by comprising.   The wiping unit according to claim 1, wherein the detection unit detects a temperature change of the wiping member.   The wiping unit according to claim 2, wherein the detection unit includes a non-contact temperature sensor that measures the temperature of the wiping member in a non-contact manner.   The wiping unit according to claim 2, wherein the detection unit includes a contact-type temperature sensor that contacts the wiping member and measures the temperature of the wiping member. A pressing member that presses the wiping member from a side opposite to the surface that is brought into contact with the liquid ejection surface of the wiping member, and causes the wiping member to contact the liquid ejection surface;
The wiping unit according to claim 4, wherein the contact-type temperature sensor is built in the pressing member.   The temperature adjusting means for adjusting the temperature of the cleaning liquid so that the temperature of the cleaning liquid sprayed from the cleaning liquid spraying means is equal to or higher than the environmental temperature is provided. Wiping unit. The detection means includes an imaging device that images the wiping member;
2. The image generating device according to claim 1, further comprising: an image generation unit configured to perform predetermined image processing on an imaging signal obtained from the imaging device to generate an image of unevenness of the cleaning liquid on the wiping member. Wiping unit.   The wiping unit according to any one of claims 1 to 7, wherein the detection unit includes a plurality of detection units arranged along a width direction orthogonal to a moving direction of the wiping member. The detection means includes a first detection unit that detects a state of the wiping member before the cleaning liquid is sprayed;
A second detector for detecting the state of the wiping member after the cleaning liquid is sprayed;
The unevenness of the cleaning liquid in the wiping member is detected based on a relative difference between a detection result by the first detection unit and a detection result by the second detection unit. The wiping unit according to item 1. The detection means is a storage means for storing information on the state of the wiping member before the cleaning liquid is sprayed;
A detection unit for detecting the state of the wiping member after the cleaning liquid is sprayed;
With
Detecting unevenness of the cleaning liquid on the wiping member based on a relative difference between the state of the wiping member before the cleaning liquid stored in the storage means is sprayed and a detection result by the detection unit. The wiping unit according to claim 1, wherein the wiping unit is characterized in that: Cleaning liquid storage means for storing the cleaning liquid supplied to the cleaning liquid spraying means;
A cleaning liquid flow path for communicating the cleaning liquid storing means and the cleaning liquid spraying means;
With
The wiping unit according to claim 1, wherein the detection unit includes a flow rate sensor that detects a flow rate of the cleaning liquid in the cleaning liquid channel. The cleaning liquid spraying means has a structure in which a plurality of spraying units are connected in the width direction of the wiping member, and a cleaning liquid flow path connected to the cleaning liquid storage means is connected for each spraying unit,
The wiping unit according to claim 11, wherein the flow rate sensor is provided in each of the cleaning liquid flow paths for the spray units. A cleaning liquid storage means for storing the cleaning liquid supplied to the cleaning liquid spraying means;
The wiping unit according to claim 1, wherein the detection unit includes a liquid amount sensor that detects a consumption amount of the cleaning liquid in the cleaning liquid storage unit. A cleaning liquid storage means for storing the cleaning liquid supplied to the cleaning liquid spraying means;
The wiping unit according to claim 13, wherein the detection unit includes a liquid level sensor that detects a liquid level of the cleaning liquid in the cleaning liquid storage unit. The moving means includes a feed roller around which the wiping member is wound,
A support roller that supports the wiping member from a side opposite to the surface of the wiping member that contacts the liquid ejection surface at a contact position where the wiping member fed from the feeding roller contacts the liquid ejection surface; ,
A take-up roll that winds up the wiping member fed from the feed roller and brought into contact with the liquid ejection surface;
A motor that rotates either the feed roller or the take-up roller;
Motor control means for controlling the motor to rotate the motor at a predetermined rotation speed so that the wiping member runs at a predetermined speed;
The wiping unit according to claim 1, comprising: A sheet-like wiping member that contacts the liquid ejection surface of the inkjet head and wipes the liquid ejection surface;
Moving means for moving the wiping member;
A cleaning liquid that is disposed on the upstream side of the contact position between the liquid discharge surface and the wiping member in the moving path of the wiping member in the moving means, and sprays the cleaning liquid onto the wiping member that is moved by the moving means. Spraying means;
In the wiping member sprayed with the cleaning liquid by the cleaning liquid spraying means, detecting means for detecting at least unevenness of the cleaning liquid in the moving direction of the moving means;
A maintenance device comprising: a wiping unit comprising: An inkjet head having a liquid ejection surface provided with a nozzle for ejecting liquid;
A wiping unit that performs a wiping process on a liquid discharge surface of the inkjet head;
Comprising
The wiping unit is a sheet-like wiping member that contacts the liquid ejection surface of the inkjet head and wipes the liquid ejection surface;
Moving means for moving the wiping member;
A cleaning liquid that is disposed on the upstream side of the contact position between the liquid discharge surface and the wiping member in the moving path of the wiping member in the moving means, and sprays the cleaning liquid onto the wiping member that is moved by the moving means. Spraying means;
In the wiping member sprayed with the cleaning liquid by the cleaning liquid spraying means, detecting means for detecting at least unevenness of the cleaning liquid in the moving direction of the moving means;
A liquid ejection apparatus comprising: A moving step of moving a sheet-like wiping member that wipes the liquid discharge surface in contact with the liquid discharge surface of the inkjet head;
A cleaning liquid spraying step of spraying the cleaning liquid onto the wiping member moved by the moving means on the upstream side of the contact position between the liquid ejection surface and the wiping member of the moving path of the wiping member in the moving step; ,
In the wiping member sprayed with the cleaning liquid in the cleaning liquid spraying step, at least a detection step of detecting an uneven coating of the cleaning liquid in the moving direction of the moving step;
A wiping method comprising:

Images