JP2014073659A - Droplet discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a droplet discharge device capable of continuously recording a high quality image.SOLUTION: In an inkjet head 200 in which a plurality of head modules 210 are joined with each other, the position of each of the head modules 210 that are mounted on a base frame 212 is detected at a predetermined detection timing and stored. Then, it is determined whether or not position displacement greater than the allowable has occurred in each of the head modules 210 on the basis of the stored position information of each of the head modules 210. When the position displacement greater than the allowable has occurred in each of the head modules 210, warning is issued.

Description

  The present invention relates to a droplet discharge device, and more particularly to a droplet discharge device having a droplet discharge head configured by connecting a plurality of head modules.

  2. Description of the Related Art An ink jet recording apparatus is known as an apparatus that forms an image on a recording medium by ejecting ink as fine ink droplets from a nozzle toward the recording medium.

  Inkjet recording devices are roughly classified into a serial system that records an image while the inkjet head reciprocates in a direction orthogonal to the conveyance direction of the recording medium, and a line system that records an image while the inkjet head is fixed without moving. Is done. The ink jet head mounted on the serial type ink jet recording apparatus is called a serial head, and the ink jet head mounted on the line type ink jet recording apparatus is called a line head.

  The serial type ink jet recording apparatus can print on a large area recording medium by extending the distance traveled by the carriage without increasing the size of the ink jet head. On the other hand, the line-type inkjet recording apparatus can perform high-speed recording because an image can be recorded over the entire recording medium without causing the inkjet head to shuttle in the main scanning direction.

  By the way, in an inkjet recording apparatus, one image is expressed by combining dots formed by ink ejected from nozzles. Therefore, in order to improve the image quality, it is necessary to reduce the dot size and increase the number of pixels per image. For this reason, in an ink jet recording apparatus, high image quality is achieved by increasing the density of nozzles.

  However, in the case of a line head, when the number of nozzles increases, there arises a problem that the yield decreases and the accumulated pitch error increases.

  Thus, Patent Documents 1 and 2 propose that a long inkjet head is manufactured by connecting a plurality of short inkjet heads (head modules). Such an ink-jet head has an advantage that even if a failure or the like occurs, only the problematic head module needs to be replaced, so that it can be economically operated.

  However, inkjet heads composed of a plurality of head modules connected to each other do not have their head modules accurately positioned and mounted, and unevenness in droplet ejection (so-called connection unevenness) such as streaks and unevenness occurs at the joints. However, there is a problem that high quality images cannot be recorded.

  In Patent Document 3, as a method of positioning and attaching each head module with high accuracy, a pair of convex portions and concave portions are formed in each head module, and the convex portions and concave portions of adjacent head modules are fitted and attached. A method has been proposed. Patent Document 4 proposes a method of attaching adjacent head modules by connecting them with a connecting bracket.

JP 2012-16904 A JP 2005-329595 A JP 2012-930 A JP 2008-194972 A

  However, in the inkjet head configured by connecting the head modules, there is a problem that the position of each head module is shifted due to vibrations received from the apparatus even if the head module is positioned and attached and continues to be used. . When this deviation occurs, there is a problem that splice unevenness occurs and the quality of the recorded image is impaired.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a droplet discharge device capable of continuously recording a high-quality image.

  Means for solving the problems are as follows.

  A first aspect is a droplet discharge head configured by connecting a plurality of head modules, each droplet being mounted on a base frame and connected to the base frame, and the droplet discharge head mounted on the base frame An attachment position adjusting means for individually adjusting the attachment position of each head module, a position detection means for detecting the position of each head module attached to the base frame at a preset detection timing, and a position detection means And a storage unit that stores information on the position of each head module.

  According to this aspect, the position of each head module attached to the base frame is monitored. That is, it is detected at a preset detection timing and stored in the storage means. Thereby, by acquiring the information on the position of each head module stored in the storage means, it is possible to grasp the state of displacement of the mounting position of each head module. This also makes it possible to correct the necessary position.

  According to a second aspect, in the liquid droplet ejection apparatus according to the first aspect, a determination unit that determines presence / absence of a positional deviation beyond an allowable amount of the head module based on information on a position of each head module stored in the storage unit. It is the aspect further provided.

  According to this aspect, the presence / absence of a positional deviation beyond the allowable range of the head module is determined based on the position information of each head module stored in the storage unit. As a result, it is possible to easily extract a head module in which a positional deviation exceeding an allowable value occurs. Whether or not the positional deviation is larger than the allowable value is determined by, for example, calculating a displacement amount from the initial position and comparing it with a threshold value. That is, it is determined that a positional deviation that is greater than or equal to an allowable value occurs when the displacement is greater than or equal to the threshold.

  The third aspect is an aspect in which the liquid droplet ejection apparatus according to the second aspect further includes warning means for issuing a warning when an unacceptable positional deviation occurs in the head module.

  According to this aspect, a warning is issued when an unacceptable displacement occurs in the head module. Thereby, it is possible to easily grasp the abnormality occurring in the droplet discharge head. The warning can be performed, for example, by issuing an alarm, emitting a warning lamp, displaying a warning message, or the like.

  According to a fourth aspect, in the liquid droplet ejection device according to the second aspect, the driving means for driving the attachment position adjusting means and the driving of the driving means are controlled when an excessive positional deviation occurs in the head module. And a position correcting means for correcting the mounting position of the head module.

  According to this aspect, when the positional deviation beyond the allowable level occurs in the head module, the mounting position of the head module is automatically corrected. As a result, the droplet discharge head can always be operated in a normal state.

  According to a fifth aspect, in the liquid droplet ejection apparatus according to the second aspect, the liquid ejection apparatus further includes ejection control means for controlling ejection of liquid droplets from each head module, and the ejection control means has a position displacement beyond an allowable range. This is a mode in which the ejection of droplets from each head module is controlled so as to correct the unevenness of droplet ejection generated at the joints of the head modules due to misalignment exceeding an allowable level.

  According to this aspect, when the positional deviation beyond the allowable level occurs in the head module, droplet ejection control is performed so as to correct the irregularity in droplet ejection (so-called joint irregularity) caused by the positional deviation. As a result, the droplet discharge head can always be operated in a normal state.

  According to a sixth aspect, in the liquid droplet ejection apparatus according to any one of the first to fifth aspects, the detection timing is when the apparatus is activated, when the liquid droplet ejection head is cleaned, when the liquid droplet ejection head is transported, This is an aspect that is at least one of when the ejection head moves and when the temperature changes.

  According to this aspect, the position of the head module is likely to occur when the apparatus is activated, when the droplet discharge head is cleaned, when the droplet discharge head is transported, when the droplet discharge head is moved, or when the temperature changes. Detection is performed. Thereby, the position of the head module can be detected efficiently. In addition, the number of operations of the position detection unit can be reduced, and the life of the position detection unit can be extended.

  According to a seventh aspect, in the liquid droplet ejection apparatus according to any one of the first to sixth aspects, the position detecting unit detects a displacement amount of the head module attached to the base frame and determines the position of the head module. This is a mode of detection.

  According to this aspect, the position of the head module is detected by detecting the amount of displacement of the head module attached to the base frame. That is, the current position of each head module is specified by the amount of displacement from the initial position.

  According to an eighth aspect, in the liquid droplet ejection apparatus according to the seventh aspect, the position detection unit is configured by a magnet provided in one of the base frame and the head module and a magnetic sensor provided in the other. is there.

  According to this aspect, the position detecting means is constituted by the magnet and the magnetic sensor. Thereby, it is possible to provide a small-sized position detection means having high resolution.

  A ninth aspect is an aspect in which, in the liquid droplet ejection apparatus of the seventh aspect, the position detection means detects the ambient temperature of the head module attached to the base frame and detects the displacement amount of the head module. .

  According to this aspect, the displacement amount of the head module is detected by detecting the ambient temperature of the head module attached to the base frame. The members constituting the base frame and the head module expand / contract due to temperature changes. As a result, the mounting position of the head module is displaced, but the amount of displacement can be obtained in advance. Therefore, in this aspect, the ambient temperature of the head module is detected, and the displacement amount of the head module is detected.

  A tenth aspect is a droplet discharge head configured by connecting a plurality of head modules, wherein each head module is attached to a base frame and connected, and the droplet discharge head is attached to the base frame. The mounting position adjusting means for individually adjusting the mounting position of each head module, the temperature detecting means for detecting the ambient temperature of the head module attached to the base frame at a preset detection timing, and the temperature detecting means And a storage unit that stores information on the ambient temperature of the head module.

  As described above, the mounting position of the head module is displaced depending on the temperature of the usage environment. Therefore, by storing the temperature information of the usage environment, it is possible to grasp the state of displacement of the mounting position of each head module. This also makes it possible to correct the necessary position.

  According to an eleventh aspect, in the droplet discharge device according to any one of the first to tenth aspects, the attachment position adjusting means is provided on a positioning reference pin provided on one of the base frame and the head module and on the other. An eccentric roller comprising an eccentric roller and biasing means for biasing the head module in the position adjustment direction of the head module and pressing and contacting the eccentric roller to the positioning reference pin. In this mode, the roller is rotated to move the head module in the head module position adjustment direction.

  According to this aspect, the attachment position adjusting means includes the positioning reference pin provided on one of the base frame and the head module, the eccentric roller provided on the other, and the urging means. Thereby, the mounting position of the head module can be adjusted with high accuracy.

  ADVANTAGE OF THE INVENTION According to this invention, the droplet discharge apparatus which can record a high quality image continuously can be provided.

Overall configuration diagram showing an overall schematic configuration of an inkjet recording apparatus Block diagram showing schematic configuration of control system of inkjet recording apparatus Bottom view showing structure of main part of inkjet head An enlarged view of a part of FIG. Front view showing the structure of the main part of an inkjet head Side view showing structure of main part of inkjet head Head module front view Rear view of the head module Side sectional view of the head module Front view showing the structure of the main part of the base frame Side sectional view showing the structure of the main part of the base frame Illustration of how to install the head module Illustration of how to install the head module Explanatory drawing of head module positioning method Explanatory drawing of head module positioning method Schematic configuration diagram of an inkjet head for monitoring the mounting position of the head module Schematic configuration diagram of inkjet head for correcting sensitivity of magnetic sensor Front view showing another example of the front view of the head module Schematic configuration diagram of the main part of an ink jet recording apparatus provided with an indicator

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

  Here, a case where the present invention is applied to an ink jet recording apparatus (droplet discharge apparatus) will be described as an example.

<< Overall configuration of inkjet recording apparatus >>
First, the overall configuration of the ink jet recording apparatus will be described.

  FIG. 1 is an overall configuration diagram showing an overall schematic configuration of an inkjet recording apparatus.

  The ink jet recording apparatus 10 is an ink jet recording apparatus that records a color image by ejecting ink of four colors of cyan (C), magenta (M), yellow (Y), and black (K) onto a sheet. . General-purpose printing paper is used for the sheet as the recording medium. Further, an ultraviolet curable aqueous ink is used as the ink.

  Here, the general-purpose printing paper is not so-called ink-jet dedicated paper but means paper mainly composed of cellulose such as coated paper used for general offset printing.

  Water-based inks are inks in which coloring materials such as dyes and pigments are dissolved or dispersed in water and water-soluble solvents. UV-curable water-based inks are cured by irradiation with ultraviolet rays (UV). This type of water-based ink.

  General-purpose printing paper has penetrability, and when an image is recorded on such a recording medium using an aqueous ink as it is, feathering, bleeding or the like occurs. For this reason, in the ink jet recording apparatus of this example, an image is recorded by applying in advance a processing liquid having a function of aggregating components in the ink.

  As shown in FIG. 1, an inkjet recording apparatus 10 mainly includes a paper feeding unit 12 that feeds paper P as a recording medium, and a surface (image recording surface) of the paper P fed from the paper feeding unit 12. A treatment liquid application unit 14 for applying the treatment liquid, a treatment liquid drying treatment unit 16 for drying the paper P coated with the treatment liquid, and ink droplets are ejected onto the surface of the dried paper P by an inkjet method. Then, an image recording unit 18 for drawing a color image, an ink drying processing unit 20 for drying the paper P on which the image is recorded, and an ultraviolet irradiation for fixing the image by irradiating the dried paper P with ultraviolet rays. And a paper discharge unit 24 that discharges and collects the paper P irradiated with ultraviolet rays.

<Paper Feeder>
The sheet feeding unit 12 feeds the sheets P stacked on the sheet feeding table 30 to the processing liquid coating unit 14 one by one. The paper feed unit 12 mainly includes a paper feed stand 30, a soccer device 32, a paper feed roller pair 34, a feeder board 36, a front pad 38, and a paper feed drum 40.

  The paper P is placed on the paper feed table 30 in a bundle state in which a large number of sheets are stacked. The sheet feed table 30 is provided so as to be lifted and lowered by a sheet feed table lifting device (not shown). The paper feed platform lifting device is driven in conjunction with the increase / decrease of the paper P stacked on the paper feed platform 30 so that the paper P positioned at the top of the bundle is always at a constant height. The paper feed table 30 is moved up and down.

  The soccer device 32 picks up the sheets P stacked on the sheet feeding table 30 one by one from the top and feeds them to the pair of sheet feeding rollers 34. The soccer device 32 includes a suction foot 32A that is movable up and down and swingable. The suction foot 32A sucks and holds the upper surface of the paper P, and the paper P is fed from the paper feed table 30 to the paper feed roller pair 34. Transport. At this time, the suction foot 32A sucks and holds the top surface of the front end side of the paper P positioned at the top of the bundle, pulls up the paper P, and the pair of paper P that constitutes the paper feed roller pair 34 is pulled up. Insert between rollers 34A, 34B.

  The paper feed roller pair 34 includes a pair of upper and lower rollers 34A and 34B that are pressed against each other. One of the pair of upper and lower rollers 34A and 34B is a drive roller (roller 34A) and the other is a driven roller (roller 34B). The drive roller (roller 34A) is driven by a motor (not shown) and rotates. The motor is driven in conjunction with the feeding of the paper P. When the paper P is fed from the soccer device 32, the motor rotates the driving roller (roller 34A) in accordance with the timing. The sheet P inserted between the pair of upper and lower rollers 34A, 34B is nipped by the rollers 34A, 34B and is sent out in the rotation direction of the rollers 34A, 34B (the installation direction of the feeder board 36).

  The feeder board 36 is formed corresponding to the paper width, and receives the paper P sent out from the paper feed roller pair 34 and guides it to the front pad 38. The feeder board 36 is installed such that the front end side is inclined downward, and the sheet P placed on the conveyance surface is slid along the conveyance surface and guided to the front pad 38.

  On the feeder board 36, a plurality of tape feeders 36A for conveying the paper P are installed at intervals in the width direction. The tape feeder 36A is formed in an endless shape, and is driven to rotate by a motor (not shown). The paper P placed on the conveyance surface of the feeder board 36 is fed by the tape feeder 36A and conveyed on the feeder board 36.

  A retainer 36B and a roller 36C are installed on the feeder board 36.

  A plurality of retainers 36 </ b> B are arranged in a longitudinal line along the conveyance surface of the paper P (two in this example). The retainer 36 </ b> B is configured by a leaf spring having a width corresponding to the sheet width, and is placed in pressure contact with the conveyance surface. The paper P conveyed on the feeder board 36 by the tape feeder 36A passes through the retainer 36B, so that the unevenness is corrected. The retainer 36 </ b> B is formed by curling the rear end portion so that the paper P can be easily introduced between the retainer 36 </ b> B and the feeder board 36.

  The roller 36C is disposed between the front and rear retainers 36B. The roller 36C is placed in pressure contact with the transport surface of the paper P. The sheet P conveyed between the front and rear retainers 36B is conveyed while the upper surface is suppressed by the rollers 36C.

  The front pad 38 corrects the posture of the paper P. The front pad 38 is formed in a plate shape and is disposed orthogonal to the transport direction of the paper P. Further, it is driven by a motor (not shown) so as to be swingable. The leading edge of the sheet P conveyed on the feeder board 36 is brought into contact with the front pad 38 to correct the posture (so-called skew prevention). The front pad 38 swings in conjunction with the paper feeding to the paper feeding drum 40 and delivers the paper P whose posture has been corrected to the paper feeding drum 40.

  The paper feed drum 40 receives the paper P fed from the feeder board 36 via the front pad 38 and conveys it to the processing liquid coating unit 14. The paper supply drum 40 is formed in a cylindrical shape and is driven to rotate by a motor (not shown). A gripper 40A is provided on the outer peripheral surface of the paper feed drum 40, and the leading edge of the paper P is gripped by the gripper 40A. The paper feed drum 40 conveys the paper P to the processing liquid coating unit 14 while winding the paper P around the peripheral surface by gripping and rotating the leading edge of the paper P with the gripper 40A.

  The paper feed unit 12 is configured as described above. The sheets P stacked on the sheet feeding table 30 are pulled up one by one in order from the top by the soccer device 32 and fed to the pair of sheet feeding rollers 34. The paper P fed to the paper feed roller pair 34 is fed forward by a pair of upper and lower rollers 34A, 34B constituting the paper feed roller pair 34 and placed on the feeder board 36. The paper P placed on the feeder board 36 is transported by a tape feeder 36 </ b> A provided on the transport surface of the feeder board 36. Then, the retainer 36B is pressed against the transport surface of the feeder board 36 in the transport process, and the unevenness is corrected. The sheet P conveyed by the feeder board 36 has its leading end brought into contact with the front pad 38 to correct the inclination, and is then transferred to the sheet feeding drum 40. Then, it is transported to the processing liquid coating unit 14 by the paper feed drum 40.

<Processing liquid application part>
The treatment liquid application unit 14 applies a treatment liquid having a function of aggregating ink on the surface (image recording surface) of the paper P. The treatment liquid application unit 14 mainly includes a treatment liquid application drum 42 that conveys the paper P, and a treatment liquid application device that applies the treatment liquid to the surface (image recording surface) of the paper P conveyed by the treatment liquid application drum 42. 44.

  The treatment liquid coating drum 42 functions as a holding unit (recording medium holding unit) for the sheet P as a recording medium, and also functions as a conveying unit (recording medium conveying unit) for the sheet P as a recording medium. The sheet P is received from the sheet feeding drum 40, held on the outer peripheral surface and rotated to convey the sheet P to the processing liquid drying processing unit 16.

  The treatment liquid coating drum 42 is formed in a cylindrical shape and is driven to rotate by a motor (not shown). A gripper 42A is provided on the outer peripheral surface of the treatment liquid coating drum 42, and the leading edge of the paper P is gripped by the gripper 42A. The processing liquid coating drum 42 conveys the paper P to the processing liquid drying processing unit 16 while rotating the paper P around the peripheral surface by rotating the gripper 42A by gripping the leading end of the paper P (one rotation). To transport one sheet of paper P). The rotation of the processing liquid coating drum 42 and the paper feed drum 40 is controlled so that the timing of receiving and delivering the paper P is matched. That is, it drives so that it may become the same peripheral speed, and it drives so that the position of a mutual gripper may match.

  The treatment liquid application device 44 functions as a treatment liquid application unit that applies the treatment liquid to the surface of the paper P conveyed by the treatment liquid application drum 42. The treatment liquid application device 44 is constituted by, for example, a roller application device, and applies a treatment liquid to the surface of the paper P by causing a coating roller having a treatment liquid applied to the peripheral surface thereof to press and contact the surface of the paper P. In addition to this, the treatment liquid coating apparatus 44 can be configured by, for example, a head that ejects and applies a treatment liquid by an inkjet method, or a spray that sprays and applies the treatment liquid.

  The treatment liquid application unit 14 is configured as described above. The paper P delivered from the paper supply drum 40 of the paper supply unit 12 is received by the processing liquid application drum 42. The treatment liquid coating drum 42 grips the leading end of the paper P with the gripper 42 </ b> A and rotates, so that the paper P is wound around the circumferential surface and conveyed. In this conveyance process, the application roller is pressed against the surface of the paper P, the application roller rolls on the paper, and the processing liquid is applied to the surface of the paper P.

  The treatment liquid applied by the treatment liquid application unit 14 is composed of a liquid containing an aggregating agent that aggregates the components in the ink composition. The flocculant may be a compound that can change the pH of the ink composition, a polyvalent metal salt, or a polyallylamine. Preferred examples of the compound capable of lowering the pH include highly water-soluble acidic substances (phosphoric acid, oxalic acid, malonic acid, citric acid, derivatives of these compounds, or salts thereof). An acidic substance may be used individually by 1 type, and may use 2 or more types together. Thereby, cohesion can be improved and the whole ink can be fixed. The pH (25 ° C.) of the ink composition is 8.0 or more, and the pH (25 ° C.) of the treatment liquid is preferably in the range of 0.5-4. As a result, it is possible to increase the image density, resolution, and speed of inkjet recording.

  The treatment liquid may contain additives such as, for example, drying inhibitors (wetting agents), antifading agents, emulsion stabilizers, penetration enhancers, ultraviolet absorbers, preservatives, antifungal agents, pH adjusters, It can contain known additives such as surface tension modifiers, antifoaming agents, viscosity modifiers, dispersants, dispersion stabilizers, rust inhibitors and chelating agents.

  By applying such a treatment liquid to the surface (image recording surface) of the paper P and recording an image, it is possible to prevent occurrence of feathering, bleeding, etc., and even if a general-purpose printing paper having permeability is used. High-quality printing can be performed.

<Processing liquid drying processing section>
The processing liquid drying processing unit 16 performs a drying process on the paper P having a processing liquid applied to the surface. The processing liquid drying processing unit 16 mainly blows hot air on the processing liquid drying processing drum 46 that transports the paper P, the paper transport guide 48, and the image recording surface of the paper P that is transported by the processing liquid drying processing drum 46. A treatment liquid drying processing unit 50 that is applied and dried is configured.

  The processing liquid drying processing drum 46 receives the paper P from the processing liquid coating drum 42 of the processing liquid coating unit 14 and conveys the paper P to the image recording unit 18. The processing liquid drying processing drum 46 is constituted by a frame assembled in a cylindrical shape, and is driven to rotate by a motor (not shown). A gripper 46A is provided on the outer peripheral surface of the processing liquid drying processing drum 46, and the leading edge of the paper P is gripped by the gripper 46A. The processing liquid drying processing drum 46 conveys the image recording unit 18 and the paper P by gripping and rotating the leading edge of the paper P with the gripper 46A. Note that the treatment liquid drying treatment drum 46 of this example is configured so that grippers 42A are disposed at two locations on the outer peripheral surface so that two sheets of paper P can be conveyed by one rotation. The rotations of the processing liquid drying processing drum 46 and the processing liquid coating drum 42 are controlled so that the timing of receiving and delivering the paper P matches each other. That is, it drives so that it may become the same peripheral speed, and it drives so that the position of a mutual gripper may match.

  The paper transport guide 48 is disposed along the transport path of the paper P by the processing liquid drying processing drum 46 and guides the transport of the paper P.

  The processing liquid drying processing unit 50 is installed inside the processing liquid drying processing drum 46 and performs drying processing by blowing hot air toward the surface of the paper P conveyed by the processing liquid drying processing drum 46. In this example, the two processing liquid drying processing units 50 are arranged in the processing liquid drying processing drum, and are configured to blow hot air toward the surface of the paper P conveyed by the processing liquid drying processing drum 46. ing.

  The processing liquid drying processing unit 16 is configured as described above. The paper P delivered from the treatment liquid application drum 42 of the treatment liquid application unit 14 is received by the treatment liquid drying treatment drum 46. The processing liquid drying processing drum 46 conveys the paper P by gripping the leading end of the paper P with the gripper 46 </ b> A and rotating. At this time, the treatment liquid drying treatment drum 46 conveys the surface of the paper P (the surface coated with the treatment liquid) inward. In the course of being conveyed by the processing liquid drying processing drum 46, the paper P is dried by blowing hot air from the processing liquid drying processing unit 50 installed inside the processing liquid drying processing drum 46. That is, the solvent component in the treatment liquid is removed. As a result, an ink aggregation layer is formed on the surface of the paper P.

<Image recording part>
The image recording unit 18 ejects ink of each color of C, M, Y, and K on the image recording surface of the paper P, and draws a color image on the image recording surface of the paper P. The image recording unit 18 mainly presses the image recording drum 52 that conveys the paper P and the paper P that is conveyed by the image recording drum 52, so that the paper P is brought into close contact with the peripheral surface of the image recording drum 52. A roller 54, a head unit 56 that records an image by discharging ink droplets of C, M, Y, and K colors on the paper P, and an inline sensor 58 that serves as an image reading unit that reads the image recorded on the paper P And a mist filter 60 for capturing ink mist and a drum cooling unit 62 for cooling the image recording drum 52.

  The image recording drum 52 functions as a recording medium holding unit that holds the paper P as a recording medium, and also functions as a recording medium conveyance unit that conveys the paper P as a recording medium. The image recording drum 52 receives the paper P from the processing liquid drying processing drum 46 of the processing liquid drying processing unit 16 and conveys the paper P to the ink drying processing unit 20. The image recording drum 52 is formed in a cylindrical shape, and is rotated by being driven by a motor (not shown) as a driving unit. A gripper is provided on the outer peripheral surface of the image recording drum 52, and the leading end of the paper P is gripped by the gripper. The image recording drum 52 conveys the paper P to the ink drying processing unit 20 while wrapping the paper P around the peripheral surface by gripping and rotating the leading edge of the paper P with this gripper. Further, the image recording drum 52 has a large number of suction holes (not shown) formed in a predetermined pattern on the peripheral surface thereof. The paper P wound around the peripheral surface of the image recording drum 52 is conveyed while being sucked and held on the peripheral surface of the image recording drum 52 by being sucked from the suction holes. Thereby, the paper P can be conveyed with high flatness.

  The paper pressing roller 54 is disposed in the vicinity of the paper receiving position of the image recording drum 52 (the position where the paper P is received from the processing liquid drying processing drum 46). The sheet pressing roller 54 is composed of a rubber roller, and is installed in press contact with the peripheral surface of the image recording drum 52. The paper P transferred from the processing liquid drying processing drum 46 to the image recording drum 52 is nipped by passing through the paper pressing roller 54 and is brought into close contact with the peripheral surface of the image recording drum 52.

  The head unit 56 includes an inkjet head (droplet ejection head) 200C that ejects cyan (C) ink droplets by an inkjet method, and an inkjet head (droplet ejection head) that ejects magenta (M) ink droplets by an inkjet method. 200M, an inkjet head (droplet ejection head) 200Y that ejects yellow (Y) ink droplets by an inkjet method, and an inkjet head (droplet ejection head) 200K that ejects black (K) ink droplets by an inkjet method It is configured with. Each of the inkjet heads 200C, 200M, 200Y, and 200K is disposed at a constant interval along the conveyance path of the paper P by the image recording drum 52.

  Each of the inkjet heads 200C, 200M, 200Y, and 200K is composed of a line head, and is formed with a length corresponding to the maximum sheet width. Each of the inkjet heads 200C, 200M, 200Y, and 200K is disposed such that the nozzle surface (surface on which the nozzles are arranged) faces the peripheral surface of the image recording drum 52.

  Each of the inkjet heads 200C, 200M, 200Y, and 200K ejects ink droplets from the nozzles formed on the nozzle surface toward the image recording drum 52, whereby an image is printed on the paper P conveyed by the image recording drum 52. Record.

  The configurations of the inkjet heads 200C, 200M, 200Y, and 200K will be described in detail later.

  The inline sensor 58 functions as an image reading unit that reads an image recorded on the paper P. The inline sensor 58 is installed on the downstream side of the rearmost inkjet head 200K with respect to the conveyance direction of the paper P by the image recording drum 52, and reads an image recorded by the inkjet heads 200C, 200M, 200Y, and 200K. The in-line sensor 58 is constituted by, for example, a line scanner, and reads an image recorded by the inkjet heads 200C, 200M, 200Y, and 200K from the paper P conveyed by the image recording drum 52.

  A contact prevention plate 59 is installed in the vicinity of the inline sensor 58 on the downstream side of the inline sensor 58. The contact prevention plate 59 prevents the paper P from coming into contact with the in-line sensor 58 when the paper P is lifted due to a conveyance failure or the like.

  The mist filter 60 is disposed between the rearmost inkjet head 200K and the inline sensor 58, and sucks air around the image recording drum 52 to capture the ink mist. In this way, by sucking the air around the image recording drum 52 and capturing the ink mist, the ink mist can be prevented from entering the in-line sensor 58 and reading errors can be prevented.

  The drum cooling unit 62 cools the image recording drum 52 by blowing cold air onto the image recording drum 52. The drum cooling unit 62 mainly includes an air conditioner (not shown) and a duct 62 </ b> A that blows cool air supplied from the air conditioner onto the peripheral surface of the image recording drum 52. The duct 62 </ b> A cools the image recording drum 52 by blowing cool air to an area other than the conveyance area of the paper P against the image recording drum 52. In this example, since the paper P is conveyed along the arc surface of the upper half of the image recording drum 52, the duct 62A blows cold air to the area of the lower half of the image recording drum 52 to record the image. The drum 52 is cooled. Specifically, the air outlet of the duct 62 </ b> A is formed in an arc shape so as to cover substantially the lower half of the image recording drum 52, and cold air is blown to the region of the substantially lower half of the image recording drum 52. Has been.

  Here, the temperature for cooling the image recording drum 52 is determined by the relationship with the temperature of the inkjet heads 200C, 200M, 200Y, and 200K (particularly the temperature of the nozzle surface), and is higher than the temperature of the inkjet heads 200C, 200M, 200Y, and 200K. It is cooled to a low temperature. Thereby, it is possible to prevent dew condensation from occurring in the inkjet heads 200C, 200M, 200Y, and 200K. That is, by making the temperature of the image recording drum 52 lower than that of the inkjet heads 200C, 200M, 200Y, and 200K, condensation can be induced on the image recording drum side, and the condensation that occurs on the inkjet heads 200C, 200M, 200Y, and 200K. (Especially, condensation on the nozzle surface) can be prevented.

  The image recording unit 18 is configured as described above. The paper P delivered from the processing liquid drying processing drum 46 of the processing liquid drying processing unit 16 is received by the image recording drum 52. The image recording drum 52 conveys the paper P by gripping the leading edge of the paper P with a gripper and rotating. The paper P delivered to the image recording drum 52 is first brought into close contact with the peripheral surface of the image recording drum 52 by passing through the paper pressing roller 54. At the same time, it is sucked from the suction holes of the image recording drum 52 and sucked and held on the outer peripheral surface of the image recording drum 52. The paper P is transported in this state and passes through the inkjet heads 200C, 200M, 200Y, and 200K. Then, during the passage, ink droplets of each color of C, M, Y, and K are ejected from the inkjet heads 200C, 200M, 200Y, and 200K onto the surface, and a color image is drawn on the surface. Since the ink aggregation layer is formed on the surface of the paper P, a high-quality image can be recorded without causing feathering or bleeding.

  The paper P on which the image is recorded by the ink jet heads 200C, 200M, 200Y, and 200K then passes through the inline sensor 58. Then, an image recorded on the surface when the in-line sensor 58 passes is read. Reading of the recorded image is performed as necessary, and an inspection such as ejection failure is performed from the read image. When reading is performed, reading is performed in a state of being held by suction on the image recording drum 52, so that reading can be performed with high accuracy. Further, since reading is performed immediately after image recording, for example, abnormalities such as ejection failure can be detected immediately, and it is possible to respond quickly. As a result, it is possible to prevent wasteful recording and minimize the occurrence of waste paper.

  Thereafter, the sheet P is transferred to the ink drying processing unit 20 after the suction is released.

<Ink drying processing section>
The ink drying processing unit 20 performs drying processing on the paper P after image recording, and removes liquid components remaining on the surface of the paper P. The ink drying processing unit 20 is transported by the chain gripper 64 that transports the paper P on which an image is recorded, the back tension applying mechanism 66 that applies back tension to the paper P transported by the chain gripper 64, and the chain gripper 64. And an ink drying processing unit 68 for drying the paper P.

  The chain gripper 64 is a paper transport mechanism commonly used in the ink drying processing unit 20, the ultraviolet irradiation unit 22, and the paper discharge unit 24. The chain gripper 64 receives the paper P delivered from the image recording unit 18 and discharges it. Transport to section 24.

  The chain gripper 64 mainly includes a first sprocket 64A installed in the vicinity of the image recording drum 52, a second sprocket 64B installed in the paper discharge unit 24, a first sprocket 64A, and a second sprocket 64B. The endless chain 64C is wound around, a plurality of chain guides (not shown) for guiding the running of the chain 64C, and a plurality of grippers 64D attached to the chain 64C at a constant interval. The first sprocket 64 </ b> A, the second sprocket 64 </ b> B, the chain 64 </ b> C, and the chain guide are each configured as a pair, and are disposed on both sides of the paper P in the width direction. The gripper 64D is installed over a chain 64C provided as a pair.

  The first sprocket 64A is installed close to the image recording drum 52 so that the paper P delivered from the image recording drum 52 can be received by the gripper 64D. The first sprocket 64A is rotatably supported by a bearing (not shown) and is connected to a motor (not shown). The chain 64C wound around the first sprocket 64A and the second sprocket 64B travels by driving this motor.

  The second sprocket 64B is installed in the paper discharge unit 24 so that the paper P received from the image recording drum 52 can be collected by the paper discharge unit 24. That is, the installation position of the second sprocket 64B is the end of the transport path of the paper P by the chain gripper 64. The second sprocket 64B is pivotally supported by a bearing (not shown) and is rotatably provided.

  The chain 64C is formed in an endless shape and is wound around the first sprocket 64A and the second sprocket 64B.

  The chain guide is arranged at a predetermined position and guides the chain 64C to travel along a predetermined path (= guides so that the paper P travels along a predetermined transport path and is transported). In the inkjet recording apparatus 10 of this example, the second sprocket 64B is disposed at a position higher than the first sprocket 64A. For this reason, a travel route in which the chain 64C is inclined in the middle is formed. Specifically, it includes a first horizontal transfer path 70A, an inclined transfer path 70B, and a second horizontal transfer path 70C.

  70 A of 1st horizontal conveyance paths are set to the same height as 1st sprocket 64A, and chain 64C wound around 1st sprocket 64A is set so that it may run horizontally.

  The second horizontal conveyance path 70C is set to the same height as the second sprocket 64B, and the chain 64C wound around the second sprocket 64B is set to travel horizontally.

  The inclined conveyance path 70B is set between the first horizontal conveyance path 70A and the second horizontal conveyance path 70C, and is set so as to connect the first horizontal conveyance path 70A and the second horizontal conveyance path 70C.

  The chain guide is disposed so as to form the first horizontal conveyance path 70A, the inclined conveyance path 70B, and the second horizontal conveyance path 70C. Specifically, it is disposed at at least a junction point between the first horizontal conveyance path 70A and the inclined conveyance path 70B and a junction point between the inclined conveyance path 70B and the second horizontal conveyance path 70C.

  A plurality of grippers 64D are attached to the chain 64C at a constant interval. The mounting interval of the gripper 64D is set in accordance with the receiving interval of the paper P from the image recording drum 52. That is, it is set according to the reception interval of the paper P from the image recording drum 52 so that the paper P sequentially delivered from the image recording drum 52 can be received from the image recording drum 52 at the same timing.

  The chain gripper 64 is configured as described above. As described above, when a motor (not shown) connected to the first sprocket 64A is driven, the chain 64C travels. The chain 64C travels at the same speed as the peripheral speed of the image recording drum 52. The timing is adjusted so that the paper P delivered from the image recording drum 52 can be received by each gripper 64D.

  The back tension applying mechanism 66 applies a back tension to the paper P that is conveyed while its leading end is gripped by the chain gripper 64. The back tension applying mechanism 66 mainly includes a guide plate 72 and a suction mechanism (not shown) that sucks air from suction holes (not shown) formed in the guide plate 72.

  The guide plate 72 is a hollow box plate having a width corresponding to the paper width. The guide plate 72 is disposed along the transport path (= chain travel path) of the paper P by the chain gripper 64. Specifically, it is disposed along the chain 64C that travels along the first horizontal transport path 70A and the inclined transport path 70B, and is disposed at a predetermined distance from the chain 64C. The sheet P conveyed by the chain gripper 64 has its back surface (the surface on which no image is recorded) sliding on the upper surface of the guide plate 72 (the surface facing the chain 64C: the sliding contact surface). Be transported.

  A large number of suction holes (not shown) are formed in a predetermined pattern on the sliding contact surface (upper surface) of the guide plate 72. As described above, the guide plate 72 is formed of a hollow box plate. A suction mechanism (not shown) sucks the hollow portion (inside) of the guide plate 72. As a result, air is sucked from the suction holes formed in the sliding contact surface.

  By sucking air from the suction holes of the guide plate 72, the back surface of the paper P conveyed by the chain gripper 64 is sucked into the suction holes. As a result, back tension is applied to the paper P conveyed by the chain gripper 64.

  As described above, since the guide plate 72 is disposed along the chain 64C that travels along the first horizontal conveyance path 70A and the inclined conveyance path 70B, the guide plate 72 conveys the first horizontal conveyance path 70A and the inclined conveyance path 70B. While it is being applied, back tension is applied.

  The ink drying processing unit 68 is installed inside the chain gripper 64 (particularly a part constituting the first horizontal transport path 70A), and performs a drying process on the paper P transported through the first horizontal transport path 70A. The ink drying processing unit 68 performs a drying process by blowing hot air onto the surface of the paper P transported through the first horizontal transport path 70A. A plurality of ink drying processing units 68 are arranged along the first horizontal conveyance path 70A. This number of installations is set according to the processing capability of the ink drying processing unit 68, the conveyance speed (= printing speed) of the paper P, and the like. That is, the sheet P received from the image recording unit 18 is set so that it can be dried while being conveyed through the first horizontal conveyance path 70A. Therefore, the length of the first horizontal conveyance path 70A is also set in consideration of the capability of the ink drying processing unit 68.

  In addition, the humidity of the ink drying process part 20 rises by performing a drying process. Since the drying process cannot be performed efficiently when the humidity increases, the ink drying processing unit 20 is provided with an exhaust unit together with the ink drying processing unit 68 to forcibly exhaust the humid air generated by the drying process. Is preferred. For example, the exhaust unit may be configured such that an exhaust duct is installed in the ink drying processing unit 20 and the air of the ink drying processing unit 20 is exhausted by the exhaust duct.

  The ink drying processing unit 20 is configured as described above. The paper P delivered from the image recording drum 52 of the image recording unit 18 is received by the chain gripper 64. The chain gripper 64 grips the leading end of the paper P with the gripper 64 </ b> D and transports the paper P along the planar guide plate 72. The paper P delivered to the chain gripper 64 is first transported along the first horizontal transport path 70A. In the process of being transported along the first horizontal transport path 70A, the paper P is dried by an ink drying processing unit 68 installed inside the chain gripper 64. That is, hot air is blown onto the surface (image recording surface) to perform a drying process. At this time, the paper P is dried while the back tension is applied by the back tension applying mechanism 66. As a result, the drying process can be performed while suppressing deformation of the paper P.

<Ultraviolet irradiation part>
The ultraviolet irradiation unit 22 fixes the image by irradiating the image recorded using the ultraviolet curable water-based ink with ultraviolet (UV). The ultraviolet irradiation unit 22 mainly transports the chain gripper 64 that transports the dried paper P, the back tension applying mechanism 66 that applies back tension to the paper P transported by the chain gripper 64, and the chain gripper 64. And an ultraviolet irradiation unit 74 that irradiates the sheet P to be irradiated with ultraviolet rays.

  As described above, the chain gripper 64 and the back tension applying mechanism 66 are used in common with the ink drying processing unit 20 and the paper discharge unit 24.

  The ultraviolet irradiation unit 74 is installed inside the chain gripper 64 (particularly, a portion constituting the inclined conveyance path 70B) and irradiates the surface of the paper P conveyed through the inclined conveyance path 70B with ultraviolet rays. The ultraviolet irradiation unit 74 includes an ultraviolet lamp (UV lamp), and a plurality of the ultraviolet irradiation units 74 are arranged along the inclined conveyance path 70B. Then, ultraviolet rays are irradiated toward the surface of the paper P that is conveyed along the inclined conveyance path 70B. The number of installed ultraviolet irradiation units 74 is set according to the conveyance speed (= printing speed) of the paper P or the like. That is, it is set so that the image can be fixed by the ultraviolet rays irradiated while the paper P is being transported along the inclined transport path 70B. Accordingly, the length of the inclined conveyance path 70B is also set in consideration of the conveyance speed of the paper P and the like.

  The ultraviolet irradiation unit 22 is configured as described above. The paper P that has been transported to the chain gripper 64 and dried by the ink drying processing unit 20 is then transported along the inclined transport path 70B. In the process of being conveyed along the inclined conveyance path 70B, the sheet P is irradiated with ultraviolet rays by an ultraviolet irradiation unit 74 installed inside the chain gripper 64. That is, ultraviolet rays are irradiated from the ultraviolet irradiation unit 74 toward the surface. At this time, the paper P is irradiated with ultraviolet rays while the back tension is applied by the back tension applying mechanism 66. Thereby, ultraviolet irradiation can be performed while suppressing deformation of the paper P. Further, since the ultraviolet irradiation unit 22 is installed in the inclined conveyance path 70B, and the inclined guide plate 72 is installed in the inclined conveyance path 70B, even when the paper P falls from the gripper 64D during conveyance. Even so, the guide plate 72 can be slid and discharged.

<Paper output section>
The paper discharge unit 24 discharges and collects the paper P on which a series of image recording processing has been performed. The paper discharge unit 24 mainly includes a chain gripper 64 that conveys the paper P irradiated with ultraviolet rays, and a paper discharge tray 76 that stacks and collects the paper P.

  As described above, the chain gripper 64 is used in common with the ink drying processing unit 20 and the ultraviolet irradiation unit 22. The chain gripper 64 releases the paper P on the paper discharge tray 76 and stacks the paper P on the paper discharge tray 76.

  The paper discharge tray 76 stacks and collects the paper P released from the chain gripper 64. The paper discharge tray 76 is provided with a sheet pad (front sheet pad, rear sheet pad, lateral sheet pad, etc.) so that the sheets P are stacked in an orderly manner (not shown).

  Further, the paper discharge tray 76 is provided so as to be lifted and lowered by a paper discharge tray lifting / lowering device (not shown). The discharge platform lifting device is controlled in conjunction with the increase / decrease of the paper P stacked on the paper discharge tray 76 so that the uppermost paper P is always positioned at a certain height. The paper table 76 is moved up and down.

<Control system>
FIG. 2 is a block diagram showing a schematic configuration of a control system of the ink jet recording apparatus according to the present embodiment.

  As shown in the figure, the inkjet recording apparatus 10 includes a system controller 100, a communication unit 102, an image memory 104, a conveyance control unit 110, a paper feed control unit 112, a processing liquid application control unit 114, a processing liquid drying control unit 116, An image recording control unit 118, an ink drying control unit 120, an ultraviolet irradiation control unit 122, a paper discharge control unit 124, an operation unit 130, a display unit 132, a nonvolatile memory 134, and the like are provided.

  The system controller 100 functions as a control unit that performs overall control of each unit of the inkjet recording apparatus 10 and also functions as a calculation unit that performs various calculation processes. The system controller 100 includes a CPU, a ROM, a RAM, and the like, and operates according to a predetermined control program. The ROM stores a control program executed by the system controller 100 and various data necessary for control.

  The communication unit 102 includes a required communication interface, and transmits / receives data to / from a host computer connected to the communication interface.

  The image memory 104 functions as a temporary storage unit for various data including image data, and data is read and written through the system controller 100. Image data captured from the host computer via the communication unit 102 is stored in the image memory 104.

  The conveyance control unit 110 controls the conveyance system of the paper P in the inkjet recording apparatus 10. That is, the drive of the tape feeder 36A, the front pad 38, and the paper supply drum 40 in the paper supply unit 12 is controlled, and the processing liquid application drum 42 in the processing liquid application unit 14 and the processing liquid drying processing drum in the processing liquid drying processing unit 16 are controlled. 46, controls the drive of the image recording drum 52 in the image recording unit 18. Further, it controls the drive of the chain gripper 64 and the back tension applying mechanism 66 that are used in common by the ink drying processing unit 20, the ultraviolet irradiation unit 22, and the paper discharge unit 24.

  The conveyance control unit 110 controls the conveyance system in accordance with a command from the system controller 100 so that the paper P is conveyed from the paper supply unit 12 to the paper discharge unit 24 without delay.

  The paper feed control unit 112 controls the paper feed unit 12 in accordance with a command from the system controller 100. More specifically, the driving of the soccer device 32 and the paper feed table raising / lowering mechanism is controlled so that the sheets P stacked on the paper feed table 30 are sequentially fed one by one without overlapping.

  The processing liquid application control unit 114 controls the processing liquid application unit 14 in accordance with a command from the system controller 100. Specifically, the drive of the treatment liquid application device 44 is controlled so that the treatment liquid is applied to the paper P conveyed by the treatment liquid application drum 42.

  The processing liquid drying control unit 116 controls the processing liquid drying processing unit 16 in accordance with a command from the system controller 100. Specifically, the drive of the processing liquid drying processing unit 50 is controlled so that the paper P conveyed by the processing liquid drying processing drum 46 is dried.

  The image recording control unit 118 controls the image recording unit 18 in accordance with a command from the system controller 100. Specifically, the drive of the inkjet heads 200C, 200M, 200Y, and 200K is controlled so that a predetermined image is recorded on the paper P conveyed by the image recording drum 52. Further, the operation of the inline sensor 58 is controlled so that the recorded image is read.

  The ink drying control unit 120 controls the ink drying processing unit 20 in accordance with a command from the system controller 100. Specifically, the drive of the ink drying processing unit 68 is controlled so that hot air is blown to the paper P conveyed by the chain gripper 64.

  The ultraviolet irradiation control unit 122 controls the ultraviolet irradiation unit 22 in accordance with a command from the system controller 100. Specifically, the drive of the ultraviolet irradiation unit 74 is controlled so that ultraviolet rays are irradiated onto the paper P conveyed by the chain gripper 64.

  The paper discharge control unit 124 controls the paper discharge unit 24 according to a command from the system controller 100. Specifically, the drive of the paper discharge table lifting mechanism is controlled so that the paper P is stacked on the paper discharge table 76.

  The operation unit 130 includes necessary operation means (for example, operation buttons, a keyboard, a touch panel, and the like), and outputs operation information input from the operation means to the system controller 100. The system controller 100 executes various processes in accordance with operation information input from the operation unit 130.

  The display unit 132 includes a required display device (for example, an LCD panel or the like), and displays required information on the display device in response to a command from the system controller 100.

  The nonvolatile memory 134 is composed of, for example, an EEPROM (electrically erasable programmable read only memory) or the like, and records various data necessary for control, various setting information, and the like.

  As described above, the image data to be recorded on the paper is taken into the inkjet recording apparatus 10 from the host computer via the communication unit 102. The captured image data is stored in the image memory 104.

  The system controller 100 performs necessary signal processing on the image data stored in the image memory 104 to generate dot data. Then, the drive of each inkjet head 200C, 200M, 200Y, 200K of the image recording unit 18 is controlled according to the generated dot data, and the image represented by the image data is recorded on the paper.

  The dot data is generally generated by performing color conversion processing and halftone processing on image data. The color conversion process is a process of converting image data expressed in sRGB or the like (for example, RGB 8-bit image data) into ink amount data of each color of ink used in the inkjet recording apparatus 10 (in this example, C, It is converted into ink amount data for each color of M, Y, and K.) The halftone process is a process of converting the ink amount data of each color generated by the color conversion process into dot data of each color by a process such as error diffusion.

  The system controller 100 performs color conversion processing and halftone processing on image data to generate dot data for each color. Then, according to the generated dot data of each color, the drive of the corresponding ink jet head is controlled to record the image represented by the image data on the paper.

  Further, as will be described later, the system controller 100 draws an image of a predetermined test pattern on the paper P when the head modules constituting the inkjet heads 200C, 200M, 200Y, and 200K are positioned, and the drawn image is displayed on the inline sensor 58. Then, the read image is processed to calculate the correction amount of the mounting position of each head module.

  Although not shown, the inkjet recording apparatus 10 includes a maintenance unit adjacent to the image recording unit 18. The maintenance unit performs maintenance of the inkjet head 200. The maintenance unit includes a cap that covers the nozzle surface of the inkjet head 200, a cleaning device that cleans the nozzle surface, and the like. The head unit 56 is movably provided between the image recording unit 18 and the maintenance unit by a head unit transfer mechanism, and maintenance processing is performed by the maintenance unit as necessary. For example, when the operation is stopped for a long period of time, the inkjet head 200 moves to the maintenance unit, and the nozzle surface is covered with a cap. Thereby, drying of a nozzle surface is prevented. Further, since the nozzle surface of the inkjet head 200 becomes dirty due to use, the nozzle surface is periodically cleaned by a cleaning device. The nozzle surface is cleaned by, for example, wiping the nozzle surface with a blade or a web.

<Recording operation by inkjet recording apparatus>
Next, the operation at the time of image recording of the inkjet recording apparatus 10 configured as described above will be described.

  When the system controller 100 is instructed to start a print job via the operation unit 130, a cycle-up process is performed. That is, preparation operations are performed in each unit so that a stable operation can be performed.

  When the cycle up is completed, the printing process is started. That is, the sheets P are sequentially fed from the sheet feeding unit 12.

  In the paper feed unit 12, the paper P stacked on the paper feed tray 30 is fed one by one by the soccer device 32 in order from the top. The paper P fed from the soccer device 32 is placed on the feeder board 36 one by one through the pair of paper feed rollers 34.

  The paper P placed on the feeder board 36 is fed by a tape feeder 36A provided on the feeder board 36, and is conveyed to the paper feed drum 40 while sliding on the feeder board 36. At this time, the sequentially fed sheets P are conveyed to the sheet feeding drum 40 while sliding on the feeder board 36 one by one without overlapping each other. Further, the upper surface is pressed toward the feeder board 36 by the retainer 36B during the conveyance process. Thereby, the unevenness is corrected.

  The paper P conveyed to the end of the feeder board 36 is delivered to the paper supply drum 40 after the front end is brought into contact with the front pad 38. Thereby, the paper P can be fed to the paper feed drum 40 in a fixed posture without causing an inclination.

  The paper feed drum 40 receives the paper P by gripping the leading end of the paper P with the gripper 40 </ b> A while rotating, and conveys the paper P toward the processing liquid coating unit 14.

  The paper P conveyed to the treatment liquid application unit 14 is transferred from the paper supply drum 40 to the treatment liquid application drum 42.

  The processing liquid coating drum 42 receives the gripper 40 </ b> A by gripping the leading end of the paper P while rotating, and transports the paper P toward the processing liquid drying processing unit 16. The processing liquid is applied to the surface of the paper P by the processing liquid coating device 44 in the process of being conveyed by the processing liquid coating drum 42.

  The sheet P having the surface coated with the processing liquid is transferred from the processing liquid coating drum 42 to the processing liquid drying processing drum 46.

  The processing liquid drying processing drum 46 grips and receives the leading edge of the paper P while rotating, and conveys the paper P toward the image recording unit 18. The sheet P is dried by hot air blown from the treatment liquid drying processing unit 50 in the process of being conveyed by the treatment liquid drying treatment drum 46 on the surface. As a result, the solvent component in the treatment liquid is removed, and an ink aggregation layer is formed on the surface (image recording surface) of the paper P.

  The paper P on which the processing liquid has been dried is transferred from the processing liquid drying processing drum 46 to the image recording drum 52.

  The image recording drum 52 grips and receives the leading edge of the paper P while rotating, and conveys the paper P toward the ink drying processing unit 20. In the process of being conveyed by the image recording drum 52, the paper P is ejected with ink droplets of C, M, Y, and K colors on the surface by the inkjet heads 200C, 200M, 200Y, and 200K, and an image is recorded. The Further, the image recorded in the conveyance process is read by the inline sensor 58. At this time, the paper P is conveyed while being sucked and held on the peripheral surface of the image recording drum 52. Then, the image is recorded and the recorded image is read while being held by suction. As a result, an image can be recorded with high accuracy, and an image can be read with high accuracy.

  The paper P on which the image is recorded is transferred from the image recording drum 52 to the chain gripper 64.

  The chain gripper 64 grips the leading end of the paper P with the gripper 64D provided in the traveling chain 64C, receives the paper P, and conveys it toward the paper discharge unit 24.

  In the course of conveyance by the chain gripper 64, the paper P is first subjected to an ink drying process. That is, hot air is blown toward the surface from the ink drying processing unit 68 installed in the first horizontal conveyance path 70A. Thereby, a drying process is performed. At this time, the paper P is conveyed while the back surface is sucked and held by the guide plate 72, and a back tension is applied. Accordingly, the drying process can be performed while suppressing deformation of the paper P.

  The paper P that has finished the drying process (the paper P that has passed through the ink drying processing unit 20) is then irradiated with ultraviolet rays. That is, ultraviolet rays are irradiated toward the surface from the ultraviolet irradiation unit 74 installed in the inclined conveyance path 70B. As a result, the ink constituting the image is cured and the image is fixed on the paper P. At this time, the paper P is conveyed while the back surface is sucked and held by the guide plate 72, and a back tension is applied. Accordingly, the fixing process can be performed while suppressing deformation of the paper P.

  The paper P that has been irradiated with the ultraviolet rays (the paper P that has passed through the ultraviolet irradiation portion 22) is conveyed toward the paper discharge portion 24, is released from the gripper 64D in the paper discharge portion 24, and is stacked on the paper discharge tray 76. Is done.

  The image recording process is completed by the series of operations described above. As described above, since the paper P is continuously fed from the paper feeding unit 12, the processing of the paper P is continuously performed in each unit.

《Head configuration》
As described above, the inkjet heads 200M, 200K, 200C, and 200Y according to the present embodiment are configured by line heads having a length corresponding to the paper width.

  In addition, since the structure of each inkjet head 200M, 200K, 200C, 200Y is the same, the structure is demonstrated as the inkjet head 200 here.

  FIG. 3 is a bottom view (a view of the head viewed from the nozzle surface side) showing the structure of the main part of the head. FIG. 4 is an enlarged view of a part of FIG. FIG. 5 is a front view showing the structure of the main part of the head. FIG. 6 is a side view showing the structure of the main part of the head.

  As shown in the figure, the inkjet head 200 is configured by connecting a plurality of head modules 210 in a line. Each head module 210 has the same structure, and is arranged in a row on the base frame 212 to constitute one inkjet head 200.

  Hereinafter, the configuration of the head module 210 and the base frame 212 will be described.

  In the following, the nozzle arrangement direction of the inkjet head 200 is defined as the X direction, the direction orthogonal to the nozzle surface is defined as the Z direction, and the direction parallel to the nozzle surface and orthogonal to the X direction is defined as the Y direction. The X direction, the Y direction, and the Z direction are orthogonal to each other.

<Head module>
The head module 210 is a so-called short head, and can record an image having a predetermined print width by itself. By connecting a plurality of head modules 210 along the direction of the nozzle row (the direction perpendicular to the transport direction of the paper P), one long head is configured.

  FIG. 7 is a front view of the head module. FIG. 8 is a rear view of the head module. FIG. 9 is a side sectional view of the head module.

  The head module 210 includes an inkjet head 214 that ejects ink and a bracket 216 that attaches the inkjet head 214 to the base frame 212.

  The inkjet head 214 is mainly composed of a head main body 218 and an electrical / piping section 220.

  The head main body 218 has a rectangular plate shape. The head main body 218 has a nozzle surface 222 on the lower surface portion. The nozzle surface 222 has a belt-like nozzle formation region 222A at the center. The nozzle formation region 222A has a certain width and is formed along the X direction. The nozzle N is formed in this nozzle formation region 222A.

  Here, in the inkjet head 214 of this example, as shown in FIG. 4, the nozzles N are arranged in a two-dimensional matrix. Specifically, they are arranged at a constant pitch along the X direction and at a constant pitch along a direction inclined by a predetermined angle with respect to the X direction. By arranging the nozzles N in this way, the substantial interval between the nozzles N projected in the X direction can be reduced. In this case, the arrangement direction of the nozzles N (the direction of the nozzle row) is the X direction. The nozzles N may be arranged in a line along the X direction.

  The electrical / pipe section 220 is an assembly of pipes, circuit boards, and the like, and is provided on the top of the head main body 218.

  The bracket 216 is formed in an L shape including a horizontal portion 224 and a vertical portion 226.

  The horizontal portion 224 functions as an attachment portion for the inkjet head 214. The vertical part 226 functions as an attachment part to the base frame 212.

  The horizontal part 224 has a rectangular plate shape. The horizontal portion 224 is formed in a shape (rectangular shape) substantially the same as the outer shape of the head main body portion 218 of the inkjet head 214. The ink jet head 214 has the head main body 218 attached to the lower surface of the horizontal portion 224. The horizontal portion 224 is provided with an opening 224 </ b> A for passing the electrical / piping portion 220 of the inkjet head 214.

  The vertical portion 226 also has a plate shape. The vertical part 226 is disposed perpendicular to the horizontal part 224, joined to one end of the horizontal part 224, and integrated with the horizontal part 224.

  The vertical portion 226 includes a vertical portion main body 226A formed with substantially the same width as the horizontal portion 224, a pair of first protruding portions 226B formed to protrude from both sides of the vertical portion main body 226A in the X direction, and a pair of A pair of second projecting portions 226C formed by projecting further in the X direction from the first projecting portion 226B is configured.

  The vertical portion 226 is provided with a head module Y-direction positioning means serving as a reference for positioning in the Y direction when the head module 210 is attached to the base frame 212, and a head module Z-direction positioning means serving as a reference for positioning in the Z direction. In addition, a part of the X direction attachment position adjusting means for fine adjustment of the attachment position in the X direction is provided.

  The head module Y direction positioning means includes two head module Y direction fixed contact members 234 that constitute the head module Y direction positioning member, and one head module Y direction movable contact member 236 that also constitutes the head module Y direction positioning member. Consists of.

  The two head module Y-direction fixed contact members 234 are provided on the second overhanging portion 226C of the vertical portion 226. The head module Y-direction fixed contact member 234 is formed of a hard sphere (a rigid sphere). The head module Y-direction fixed contact member 234 is inserted into a hole (not shown) formed in the second overhang portion 226C, and the inner surface of the second overhang portion 226C (when the head module 210 is attached to the base frame 212) A part of the surface facing the base frame 212).

  On the other hand, the head module Y-direction movable contact member 236 is provided on the vertical portion main body 226A of the vertical portion 226. The head module Y-direction movable contact member 236 is formed of a rigid sphere, and is inserted into the head module Y-direction movable contact member insertion hole 238 formed in the vertical portion main body 226A, and is provided in the vertical portion main body 226A. The head module Y-direction movable contact member insertion hole 238 is formed along the Y direction and is formed so as to penetrate from the outer surface to the inner surface of the vertical portion main body 226A. The head module Y-direction movable contact member 236 is inserted into the head module Y-direction movable contact member insertion hole 238 so as to protrude from the inner surface of the vertical portion main body 226A. The head module Y-direction movable contact member insertion hole 238 is formed by reducing the diameter of the inner surface side of the vertical portion main body 226A so that the head module Y-direction movable contact member 236 does not fall off.

  The head module Y-direction movable contact member insertion hole 238 is a screw hole, and the head module Y-direction movable contact member position adjusting screw 240 is screwed together. The head module Y-direction movable contact member position adjusting screw 240 is constituted by a so-called potato screw (a screw head having the same size as the screw portion). By adjusting the screwing amount of the head module Y-direction movable contact member position adjusting screw 240, the protrusion amount of the head module Y-direction movable contact member 236 from the inner surface of the vertical portion main body 226A is adjusted.

  As will be described later, the head module Y-direction fixed contact member 234 and the head module Y-direction movable contact member 236 are fixed contact base frame Y provided on the base frame 212 side when the head module 210 is attached to the base frame 212. The direction positioning member 290 and the movable contact base frame Y direction positioning member 292 are brought into contact with each other. As a result, the head module 210 is positioned in the Y direction with respect to the base frame 212.

  The head module Z direction positioning means is composed of a pair of head module Z direction contact members 242 constituting a head module Z direction positioning member.

  The pair of head module Z-direction contact members 242 are provided on the first overhanging portion 226 </ b> B of the vertical portion 226. The head module Z direction contact member 242 is formed of a hard sphere. The head module Z-direction contact member 242 is inserted into the head module Z-direction contact member insertion hole 244 formed in the first overhang portion 226B, and is provided in the first overhang portion 226B. The head module Z-direction contact member insertion hole 244 is formed along the Z direction and is formed so as to penetrate from the lower surface to the upper surface of the first overhang portion 226B. The head module Z-direction contact member 242 is inserted into the head module Z-direction contact member insertion hole 244, and a part thereof is provided so as to protrude from the upper surface of the first overhang portion 226B. The head module Z direction contact member insertion hole 244 is formed by reducing the diameter of the upper surface side of the first overhanging portion 226B so that the head module Z direction contact member 242 does not fall off.

  The head module Z direction contact member insertion hole 244 is configured by a screw hole. A head module Z direction contact member position adjusting screw 246 is screwed into the head module Z direction contact member insertion hole 244. The head module Z-direction contact member position adjusting screw 246 is constituted by a so-called potato screw. By adjusting the screwing amount of the head module Z direction contact member position adjusting screw 246, the amount of protrusion of the head module Z direction contact member 242 from the upper surface of the first overhanging portion 226B is adjusted.

  As will be described later, the head module Z-direction contact member 242 comes into contact with a base frame Z-direction contact member 294 provided on the base frame 212 side when the head module 210 is attached to the base frame 212. As a result, the head module 210 is positioned in the Z direction with respect to the base frame 212.

  The pair of head module Z-direction contact members 242 are set so that the installation interval (X-direction installation interval) is longer than the print area width of the inkjet head 214 (total nozzle row length). Is preferred. Thereby, the stability at the time of sitting increases and the positioning precision of a Z direction can be improved.

  Similarly, for the pair of head modules Y direction fixed contact member 234, the installation interval (installation interval in the X direction) is longer than the print area width (total nozzle row length) of the inkjet head 214. It is preferable to set so. Thereby, the stability at the time of sitting increases and the positioning accuracy in the Y direction can be improved.

  The X direction attachment position adjusting means (attachment position adjusting means) is mainly composed of an eccentric roller 248, a plunger 250, and an X direction positioning reference pin (positioning reference pin) 296. The eccentric roller 248 and the plunger 250 are provided on the head module 210, and the X-direction positioning reference pin 296 is provided on the base frame 212.

  The eccentric roller 248 and the plunger 250 are disposed on the inner surface side of the vertical portion main body 226A. The eccentric roller 248 and the plunger 250 are arranged to face each other with a constant interval.

  The eccentric roller 248 includes a shaft portion 248A and a roller portion 248B. The shaft portion 248A functions as a rotation shaft for rotating the roller portion 248B, and is eccentrically connected to the roller portion 248B. For this reason, when the shaft portion 248A is rotated, the roller portion 248B is eccentrically rotated.

  The shaft portion 248A of the eccentric roller 248 is constituted by a male screw. The shaft portion 248A is inserted into the eccentric roller mounting hole 252 of the vertical portion main body 226A. The eccentric roller mounting hole 252 is a screw hole and is formed in parallel with the Y direction. The eccentric roller mounting hole 252 is formed to penetrate from the outer surface side to the inner surface side of the vertical portion main body 226A. The eccentric roller 248 is attached to the vertical portion main body 226A by screwing the shaft portion 248A into the eccentric roller attachment hole 252. A groove (+ or − groove) for rotating the shaft portion 248A with a screw driver is formed on the end surface of the shaft portion 248A of the eccentric roller 248. The eccentric roller 248 attached to the vertical portion main body 226A rotates by rotating the shaft portion 248A using a screw driver, whereby the roller portion 248B is eccentric.

  A plate spring 254 is pressed against the roller portion 248B. The leaf spring 254 is disposed on the inner surface side of the vertical portion main body 226A. The leaf spring 254 is brought into contact with the peripheral surface of the roller portion 248B and presses the roller portion 248B in the axial direction. The roller portion 248 </ b> B is given a certain resistance to rotation by the leaf spring 254.

  The plunger 250 functions as X direction urging means. The plunger 250 is disposed along the X direction, and the tip (pressing portion) is disposed to face the eccentric roller 248.

  As described above, the eccentric roller 248 and the plunger 250 are arranged to face each other with a constant interval. When the head module 210 is attached to the base frame 212, the X-direction positioning reference pin 296 provided on the base frame side is fitted between the eccentric roller 248 and the plunger 250 and is sandwiched between the eccentric roller 248 and the plunger 250. The The plunger 250 presses the X-direction positioning reference pin 296 in the X direction. As a result, the head module 210 is biased in the X direction. When the eccentric roller 248 is rotated in this state, the head module 210 moves in the X direction according to the rotation amount.

  A guide groove 256 for attaching the bracket 216 to the base frame 212 is further formed in the vertical portion 226 of the bracket 216. The guide groove 256 is formed in the vertical portion main body 226A of the vertical portion 226, and has a predetermined depth and a predetermined depth from the upper surface portion of the vertical portion main body 226A vertically downward (Z direction). The guide groove 256 is fitted with a pair of Y-direction guide posts 276 provided on the base frame side when the bracket 216 is attached to the base frame 212. For this reason, the width of the guide groove 256 is formed to be substantially the same as the width (diameter) of the Y direction guide post 276. Thereby, interference with the adjacent head module 210 can be prevented.

  The guide groove 256 has an arc-shaped enlarged diameter portion 256 </ b> A formed at the tip (lower end) and substantially the center. When the head module 210 is attached to a predetermined position of the base frame 212, a pair of Y direction guide posts 276 provided on the base frame side is accommodated in the enlarged diameter portion 256A. As a result, the head module 210 attached to the base frame 212 is movably supported.

  As described above, the enlarged diameter portion 256A of the guide groove 256 is provided to support the head module 210 so that the head module 210 is movable, so that the formation position is formed corresponding to the Y-direction guide post 276, and the head module 210 is attached to the base frame. When attached to 212, the Y-direction guide post 276 is formed so as to be accommodated at substantially the center position thereof. Here, when the head module 210 is attached to the base frame 212, the enlarged diameter portion 256A is formed so as to form a circle centered on the axis of the Y-direction guide post 276. This circle is formed larger than the diameter of the Y direction guide post 276. Thereby, when the head module 210 is attached to the base frame 212, the head module 210 can be supported so as to be movable within a predetermined range. Further, when the head module 210 is attached to the base frame 212, the head module 210 can be attached without causing backlash.

  A pair of notches 258A and 258B are formed on the inner wall surface of the guide groove 256. When the bracket 216 is attached to the base frame 212, the pair of notches 258A and 258B are engaged with the locking bar 288 of the Z-direction hanging rod 278 provided on the base frame side. The bracket 216 is locked to the base frame 212 when the locking bar 288 of the Z-direction hanging rod 278 is engaged with the notches 258A and 258B. The notches 258A and 258B are formed at positions facing the inner wall surface of the guide groove 256, and are formed with a predetermined depth on the inner surface side and the outer surface side of the vertical portion 226 of the bracket 216, respectively. That is, one notch portion 258A is formed on the outer surface side of the vertical portion 226, and the other notch portion 258B is formed on the inner surface side.

  Furthermore, a magnet 260 for detecting the amount of displacement (movement amount) of the head module 210 when the head module 210 is attached to the base frame 212 is provided in the vertical portion 226 of the bracket 216. This magnet 260 constitutes a position detecting means together with the magnetic sensor 298 provided on the base frame 212 side. When the head module 210 is attached to the base frame 212, the magnet 260 is disposed to face the magnetic sensor 298 provided on the base frame 212 side.

  The head module 210 is configured as described above.

<base frame>
FIG. 10 is a front view showing the structure of the main part of the base frame. FIG. 11 is a side sectional view showing the structure of the main part of the base frame.

  The base frame 212 mainly includes an upper frame portion 270 and a pair of lower frame portions 272A and 272B.

  The upper frame part 270 has a rectangular plate shape. The upper frame part 270 is disposed horizontally (parallel to the XY plane). The pair of lower frame portions 272A and 272B have a rectangular plate shape. The pair of lower frame parts 272A and 272B are arranged perpendicularly (parallel to the XZ plane) to the lower part of the upper frame part 270 with a constant interval.

  The pair of lower frame portions 272A and 272B function as attachment portions for attaching the head module 210. The head module 210 is alternately attached to the pair of lower frame portions 272A and 272B. That is, if one lower frame portion 272A is a first lower frame (first mounting portion) and the other lower frame portion 272B is a second lower frame (second mounting portion), the first head module 210 is the first head module 210. The second head module 210, which is attached to the lower frame portion 272A and arranged next to the lower frame portion 272A, is attached to the second lower frame portion 272B. The third head module 210 arranged next to the second head module 210 is attached to the first lower frame portion 272A, and the fourth head module arranged next to the second head module 210 is attached to the second lower frame. It is attached to the part 272B. In this manner, the head module 210 is alternately attached to the first lower frame portion 272A and the second lower frame portion 272B.

  The base frame 212 is provided with a head module support means for supporting the head module 210. The head module support means is prepared for each head module. As described above, since the head module 210 is alternately attached to the pair of lower frame portions 272A and 272B, the head module support means is provided alternately to the pair of lower frame portions 272A and 272B. Therefore, the installation interval (X-direction installation interval) of the head module support means coincides with the installation interval (X-direction installation interval) of the head module 210 attached to each lower frame portion 272A, 272B.

  The head module support means includes a pair of Y direction guide posts 276 and a Z direction hanging rod 278.

  The pair of Y-direction guide posts 276 are arranged in parallel in the vertical direction (Z direction) with a constant interval. The Y direction guide post 276 is formed in a cylindrical shape. The Y-direction guide post 276 has a flange portion 276A at the top. The Y-direction guide post 276 is provided so as to protrude from the outer surface of the lower frame portions 272A and 272B, and is disposed in parallel with the Y direction. The width (diameter) of the Y direction guide post 276 is formed to be approximately the same as the width of the guide groove 256.

  As described above, when the head module 210 is attached to the base frame 212, the guide groove 256 formed in the vertical portion 226 of the bracket 216 is fitted into the pair of Y direction guide posts 276. Since the width (diameter) of the Y-direction guide post 276 is formed substantially the same as the width of the guide groove 256, the Y-direction guide post 276 can be attached without rattling.

  Each of the pair of Y direction guide posts 276 is provided with a Y direction pressing plate 280. The Y-direction pressing plate 280 is formed in a ring shape. The Y-direction pressing plate 280 is provided on the Y-direction guide post 276 with the Y-direction guide post 276 inserted through the inner periphery thereof.

  Each of the pair of Y direction guide posts 276 is provided with a Y direction pressing spring 282. The Y-direction pressing spring 282 is provided on the Y-direction guide post 276 with the Y-direction guide post 276 inserted through the inner periphery thereof. The Y-direction pressing spring 282 is disposed between the flange portion 276 </ b> A of the Y-direction guide post 276 and the Y-direction pressing plate 280.

  As described above, when the head module 210 is attached to the base frame 212, the pair of Y-direction guide posts 276 are fitted into the guide grooves 256. When the pair of Y-direction guide posts 276 are fitted into the guide grooves 256, the Y-direction pressing plate 280 engages with the vertical portion 226 of the bracket 216. Since the Y direction pressing plate 280 is urged in the Y direction by the Y direction pressing spring 282, the head module 210 is pressed toward the base frame 212 by the Y direction pressing plate 280.

  Here, the pair of Y-direction guide posts 276 are arranged at regular intervals in the vertical direction as described above, but the Y-direction pressing springs 282 provided in each Y-direction guide post 276 have different urging forces, that is, Different spring constants are used. Specifically, the Y-direction pressing spring 282 provided in the lower Y-direction guide post 276 has a larger spring constant than the Y-direction pressing spring 282 provided in the upper Y-direction guide post 276. The As a result, the pressing force by the Y-direction pressing plate 280 provided on the lower Y-direction guide post 276 is larger than the pressing force by the Y-direction pressing plate 280 provided on the upper Y-direction guide post 276. This is to prevent the head module 210 from tilting when adjusting the attachment position in the X direction. That is, by increasing the spring constant of the Y-direction pressing spring 282 provided in the lower Y-direction guide post 276 close to the X-direction mounting position adjusting means, the center of the rotational moment when adjusting the mounting position in the X direction is adjusted to the X direction. It is set near the mounting position adjusting means, and the head module 210 can be prevented from tilting. (When the spring constant of the Y-direction pressing spring 282 provided in the upper Y-direction guide post 276 is increased, The side will be harder to move and will be easier to tilt.)

  In the inkjet head 200 of the present embodiment, the X-direction attachment position adjusting means is provided in the vicinity of the lower Y-direction guide post 276, and therefore the Y-direction provided in the lower Y-direction guide post 276. The spring constant of the pressing spring 282 is larger than the spring constant of the Y-direction pressing spring 282 provided in the upper Y-direction guide post 276, but the X-direction mounting position adjusting means is close to the upper Y-direction guide post 276. Is provided, the spring constant of the Y-direction pressing spring 282 provided in the upper Y-direction guide post 276 is made larger than the spring constant of the Y-direction pressing spring 282 provided in the lower Y-direction guide post 276. . That is, the spring constant of the Y-direction pressing spring 282 of the Y-direction guide post 276 installed closer to the X-direction mounting position adjusting means is larger than the spring constant of the Y-direction pressing spring 282 of the Y-direction guide post 276 on the other side. To do. Thereby, the inclination of the head module 210 at the time of adjusting the attachment position in the X direction can be prevented.

  The Z direction hanging rod 278 is formed in a cylindrical shape. The Z-direction hanging rod 278 has a knob portion 278A at the top. The Z direction hanging rod 278 is arranged in parallel with the Z direction. In the upper frame portion 270, a Z-direction hanging rod insertion hole 284 for attaching the Z-direction hanging rod 278 is formed. The Z-direction hanging rod insertion hole 284 is formed along the Z direction and is formed to penetrate from the upper surface portion of the upper frame portion 270 to the lower surface portion. The Z-direction hanging rod 278 is inserted into the Z-direction hanging rod insertion hole 284 and attached to the upper frame portion 270.

  The Z-direction hanging rod 278 attached to the upper frame portion 270 is disposed in front of the outer surface of the lower frame portions 272A and 272B.

  Further, the Z-direction hanging rod 278 is disposed on the same straight line as the pair of Y-direction guide posts 276 and is disposed above the pair of Y-direction guide posts 276. Therefore, when the head module 210 is attached to the base frame 212, the Z-direction hanging rod 278 is accommodated in the guide groove 256.

  The Z-direction hanging rod 278 is provided with a Z-direction pressing spring 286. The Z-direction pressing spring 286 is provided on the Z-direction hanging rod 278 with the Z-direction hanging rod 278 inserted through the inner periphery thereof. The Z-direction pressing spring 286 is provided between the knob portion 278 </ b> A of the Z-direction hanging rod 278 and the upper frame portion 270. As a result, the Z-direction hanging rod 278 is biased upward by the biasing force of the Z-direction pressing spring 286 (biased in the direction of pulling up toward the upper frame portion 270).

  Further, the Z-direction hanging rod 278 is provided with a locking bar 288 at the tip (lower end). The locking bar 288 is provided so as to protrude left and right from the tip of the Z-direction hanging rod 278 (provided perpendicular to the axial direction of the Z-direction hanging rod 278). The locking bar 288 is formed longer than the width of the guide groove 256. The locking bar 288 is fitted into the notches 258A and 258B formed in the guide groove 256 on the head module 210 side to lock the head module 210.

  The locking bar 288 is fitted into the notches 258A and 258B by rotating the Z-direction hanging rod 278. That is, as described above, the lock bar 288 is formed to be longer than the width of the guide groove 256, so that the head module 210 is placed in the state in which it is directed in the same direction as the width direction (X direction) of the guide groove 256. When attached to the frame 212, the locking bar 288 comes into contact with the inlet portion (upper end portion) of the guide groove 256, and the head module 210 cannot be attached.

  Therefore, when the head module 210 is attached to the base frame 212, the lock bar 288 is positioned so as not to contact the inner wall surface of the guide groove 256, and the head module 210 is attached to the base frame 212 in this state. Then, when the head module 210 is attached to the base frame 212 and the locking bar 288 is located at the position where the notches 258A and 258B are formed, the Z-direction hanging rod 278 is rotated. As a result, the locking bar 288 fits into the notches 258A and 258B.

  As described above, when the axial direction of the locking bar 288 is parallel to the width direction (X direction) of the guide groove 256, the locking bar 288 is fitted into the notches 258A and 258B. The position of the lock bar 288 at this time is defined as a lock position.

  On the other hand, when the axial direction of the locking bar 288 is orthogonal to the width direction (X direction) of the guide groove 256, it does not come into contact with the inner wall surface of the guide groove 256 (disengages from the notches 258A and 258B). The position of the lock bar 288 at this time is defined as a lock release position.

  Since the Z-direction hanging rod 278 is biased upward by the Z-direction pressing spring 286, when the locking bar 288 is fitted into the notches 258A, 258B, the locking bar 288 is notched at the notches 258A, Engage with 258B (engage with the ceiling surface of the inner periphery of the notches 258A, 258B). Thereby, the head module 210 attached to the base frame 212 is urged upward.

  The base frame 212 includes a base frame Y-direction positioning means for positioning in the Y direction when the head module 210 is attached to the base frame 212, and a base frame Z-direction positioning means for positioning in the Z direction. It is done.

  The base frame Y direction positioning means includes two fixed contact base frame Y direction positioning members 290 constituting the base frame Y direction positioning member and one movable contact base frame Y direction which also constitutes the base frame Y direction positioning member. And a positioning member 292.

  The two fixed contact base frame Y direction positioning members 290 are each composed of a pin having rigidity (for example, a pin made of stainless steel), and has a higher hardness than the head module Y direction fixed contact member 234. The two fixed contact base frame Y-direction positioning members 290 are provided so as to protrude downward (downward in the Z direction) from the lower surface portions of the lower frame portions 272A and 272B, respectively. The two fixed contact base frame Y direction positioning members 290 are provided at the same interval as the installation interval of the two head module Y direction fixed contact members 234 provided on the head module 210 side, and the head module 210 is attached to the base frame 212. In this case, the two head module Y-direction fixed contact members 234 are provided at positions where they contact the peripheral surface. That is, the two fixed contact base frame Y direction positioning members 290 are provided corresponding to the two head module Y direction fixed contact members 234 provided on the head module 210 side.

  The movable contact base frame Y-direction positioning member 292 is configured with a rigid pin (for example, a stainless steel pin) and is configured with higher hardness than the head module Y-direction movable contact member 236. The movable contact base frame Y-direction positioning member 292 is housed in a recess formed on the outer surface of the lower frame portions 272A, 272B and disposed on the lower frame portions 272A, 272B. The movable contact base frame Y-direction positioning member 292 is arranged in parallel with the Y direction. When the head module 210 is attached to the base frame 212, the movable contact base frame Y direction positioning member 292 is provided at a position where the head module Y direction movable contact member 236 on the head module 210 side comes into contact with the front end surface thereof. That is, the movable contact base frame Y-direction positioning member 292 is provided corresponding to the head module Y-direction movable contact member 236 provided on the head module 210 side.

  As described above, when the head module 210 is attached to the base frame 212, the head module 210 is pressed toward the base frame 212 by the Y-direction pressing plate 280 provided in the Y-direction guide post 276. Accordingly, when the head module 210 is attached to the base frame 212, the two head module Y-direction fixed contact members 234 provided on the head module 210 side become the two fixed contact base frame Y-directions provided on the base frame 212 side. It is pressed against the positioning member 290. The head module Y-direction movable contact member 236 provided on the head module 210 side is pressed and brought into contact with the movable contact base frame Y-direction positioning member 292 provided on the base frame 212 side. Thereby, the head module 210 attached to the base frame 212 is positioned in the Y direction with respect to the base frame 212.

  As described above, the fixed contact base frame Y direction positioning member 290 is configured with higher hardness than the head module Y direction fixed contact member 234, and the movable contact base frame Y direction positioning member 292 is formed of the head module Y. The directional movable contact member 236 is configured with higher hardness. Thereby, the position stability at the time of positioning can be improved, and the repeatability when the head module 210 is replaced can be improved.

  As a method for increasing the hardness, a material having a high hardness can be used, or a method for increasing the hardness by applying a surface treatment can be employed.

  Base frame Z direction positioning means for positioning the head module 210 in the Z direction with respect to the base frame 212 includes a pair of base frame Z direction contact members 294.

  The pair of base frame Z-direction contact members 294 are configured by rigid pins (for example, stainless steel pins) and are formed with higher hardness than the head module Z-direction contact member 242. The pair of base frame Z-direction contact members 294 are provided so as to protrude from the outer surfaces of the lower frame portions 272A and 272B, respectively, and are disposed in parallel with the Y direction. The pair of base frame Z-direction contact members 294 are provided at the same interval as the installation interval of the pair of head module Z-direction contact members 242 provided on the head module 210 side, and when the head module 210 is attached to the base frame 212, The head module Z-direction contact member 242 is provided at a contact position. That is, the pair of base frame Z-direction contact members 294 are provided corresponding to the head module Z-direction contact member 242 provided on the head module 210 side.

  As described above, when the head module 210 is attached to the base frame 212, the head module 210 is biased upward by the action of the Z-direction pressing spring 286 provided on the Z-direction hanging rod 278. Therefore, when the head module 210 is attached to the base frame 212, the pair of head module Z-direction contact members 242 provided on the head module 210 abut on the pair of base frame Z-direction contact members 294 provided on the base frame 212. Is done. As a result, the head module 210 is positioned in the Z direction with respect to the base frame 212.

  As described above, the base frame Z-direction contact member 294 is formed with higher hardness than the head module Z-direction contact member 242. Thereby, the position stability at the time of positioning can be improved, and the repeatability when the head module 210 is replaced can be improved.

  As a method for increasing the hardness, a material having a high hardness can be used, or a method for increasing the hardness by applying a surface treatment can be employed.

  The base frame 212 is provided with an X-direction positioning reference pin 296 that is a constituent member of the X-direction attachment position adjusting means. The X-direction positioning reference pin 296 is configured by a rigid pin (for example, a stainless steel pin), and is provided to protrude downward (downward in the Z direction) from the lower surface of the lower frame portions 272A and 272B. The X-direction positioning reference pin 296 is disposed at a position where the X-direction positioning reference pin 296 is fitted between the eccentric roller 248 provided on the head module 210 side and the plunger 250 when the head module 210 is attached to the base frame 212.

  When the head module 210 is attached to the base frame 212, the X-direction positioning reference pin 296 is inserted between the eccentric roller 248 and the plunger 250 and is sandwiched between them. When the eccentric roller 248 is rotated in this state, the head module 210 is displaced in the X direction with respect to the base frame 212.

  Further, the base frame 212 is provided with a magnetic sensor 298 that constitutes a position detecting means together with the magnet 260 provided on the head module 210 side. The magnetic sensor 298 is provided in the lower frame portions 272A and 272B. The lower frame portions 272A and 272B are provided with a magnetic sensor mounting portion 300 at a predetermined position. The magnetic sensor 298 is attached to the magnetic sensor mounting part 300. When the head module 210 is attached to the base frame 212, the magnetic sensor 298 attached to the magnetic sensor mounting portion 300 is disposed at a position facing the magnet 260 provided on the head module 210 side.

  When the head module 210 attached to the base frame 212 is displaced in the X direction by the X direction attachment position adjusting means, the amount of displacement is detected by the magnetic sensor 298. Information on the amount of displacement detected by the magnetic sensor 298 is output to the system controller 100.

  The base frame 212 is configured as described above.

  The material of the base frame 212 is not particularly limited, but it is preferable to use a material that is not easily affected by heat so that the head module 210 can be attached with high accuracy. Specifically, it is preferable to form a material having a linear expansion coefficient of 10 ppm / ° C. or lower, which is lower than the iron-based linear expansion coefficient (about 15 ppm / ° C.). Thereby, it is possible to prevent the mounting position of the head module 210 from being changed due to the influence of heat. As such a material, for example, ceramics, invar, and super invar can be used.

<How to install the head module>
Next, a method for attaching the head module 210 will be described.

  As described above, the base frame 212 is provided with the head module support means, and the head module 210 is attached to the base frame 212 using the head module support means.

  The head module support means is alternately provided on the pair of lower frame portions 272A and 272B. Therefore, the head module 210 is alternately attached to the pair of lower frame portions 272A and 272B. In addition, since the attachment method itself is the same everywhere, the case where it attaches to the lower frame part 272A is demonstrated here.

  The head module 210 is attached to the base frame 212 by an operation of pushing it upward from the bottom of the base frame 212.

  First, the horizontal portion 224 of the bracket 216 of the head module 210 is set in a posture parallel to the upper frame portion 270 of the base frame 212 at a position below the base frame 212. Further, the vertical portion 226 of the bracket 216 is set in a posture parallel to the lower frame portion 272A of the base frame 212. In this state, the position of the guide groove 256 formed in the bracket 216 of the head module 210 is aligned with the position of the Y-direction guide post 276 provided in the lower frame portion 272A of the base frame 212.

  Next, as shown in FIGS. 12 and 13, the head module 210 is pushed up toward the base frame 212 so that the Y-direction guide posts 276 fit into the guide grooves 256. When the Y-direction guide post 276 is fitted into the guide groove 256, the head module 210 is pushed up vertically using the Y-direction guide post 276 as a guide. Thereby, blurring and rattling at the time of attachment can be prevented, and the head module 210 can be prevented from coming into contact with other members (such as the attached head module 210).

  When the Y-direction guide post 276 is fitted in the guide groove 256 and the head module 210 is pushed up, the Z-direction hanging rod 278 provided on the base frame 212 is accommodated in the guide groove 256.

  Here, the Z-direction hanging rod 278 is provided with a locking bar 288. When the head module 210 is attached to the base frame 212, the locking bar 288 is positioned at the unlocking position so that the locking bar 288 does not contact the inner wall surface of the guide groove 256. Accordingly, it is possible to prevent the lock bar 288 from coming into contact with the entrance portion of the guide groove 256 and hindering the movement of the head module 210.

  When the head module 210 is pushed up toward the base frame 212 as described above, the pair of head module Z-direction contact members 242 provided on the bracket 216 of the head module 210 are paired with the pair of base frames provided on the base frame 212. It abuts on the Z-direction contact member 294. When the pair of head module Z-direction contact members 242 are brought into contact with the pair of base frame Z-direction contact members 294 provided on the base frame 212, the pair of head modules 210 are formed in the guide grooves 256 of the head module 210. The notches 258 </ b> A and 258 </ b> B are located at the installation position of the lock bar 288 provided on the Z-direction hanging rod 278. In this state, the Z-direction hanging rod 278 is rotated, and the lock bar 288 is positioned at the lock position. As a result, the locking bar 288 fits into the notches 258A and 258B, and the locking bar 288 is locked to the ceiling surface of the inner periphery of the notches 258A and 258B. Thereby, the head module 210 is attached to the base frame 212 in a state of being suspended by the Z-direction suspension rod 278.

  Here, the Z-direction hanging rod 278 is provided with a Z-direction pressing spring 286. Therefore, when the Z-direction suspension rod 278 is engaged, the head module 210 is pushed upward by the action of the Z-direction pressing spring 286. As a result, the pair of head module Z direction contact members 242 provided on the head module 210 abut on the pair of base frame Z direction contact members 294 provided on the base frame 212. As a result, the head module 210 is positioned in the Z direction with respect to the base frame 212.

  A pair of Y direction guide posts 276 fitted in the guide groove 256 is provided with a Y direction pressing spring 282. The Y direction pressing spring 282 presses the head module 210 toward the base frame 212 via the Y direction pressing plate 280. As a result, the head module Y-direction fixed contact member 234 and the head module Y-direction movable contact member 236 provided on the head module 210 are connected to the base frame Y-direction positioning member 290 for fixed contacts provided on the base frame 212 and the movable contact. The base frame Y direction positioning member 292 is pressed against and abutted on. As a result, the head module 210 is positioned in the Y direction with respect to the base frame 212.

  When the head module Z-direction contact member 242 is brought into contact with the base frame Z-direction contact member 294, the Y-direction guide post 276 is accommodated in the enlarged diameter portion 256A formed in the guide groove 256. Thereby, the head module 210 is attached to the base frame 212 in a state displaceable in the X direction.

  The head module Z-direction contact member 242 and the head module Y-direction movable contact member 236 can be adjusted in position, but this position adjustment is preferably performed in advance (for example, performed at the time of factory shipment).

  As described above, the head module 210 is attached to the base frame 212. This operation is performed for all the head modules 210. As described above, since the head modules 210 are alternately attached to the base frame 212, the attachment is performed alternately.

  The attachment is preferably performed in order from one end of the base frame 212 to the other. At this time, it is preferable that the first head module 210 (the head module 210 to be attached first) is attached in accordance with the median value of the adjustment range of the displacement amount in the X direction. Accordingly, it is possible to reduce the risk that the subsequent mounting position of the head module 210 is out of the adjustment range, and it is possible to prevent the adjustment range from being unnecessarily large.

  The base frame 212 to which the head module 210 is attached is held by a predetermined holder provided in the ink jet recording apparatus 10 and mounted on the ink jet recording apparatus 10.

《Head module positioning method》
The head module 210 is attached to the base frame 212 by the above attachment operation. However, this attachment is a rough attachment (temporary attachment). Thereafter, the interval between the head modules adjacent to each other is adjusted precisely so that no gap is generated in the nozzle row at the joint of the head modules 210. That is, the head module 210 is positioned. Hereinafter, a method for positioning the head module 210 will be described.

  The positioning of the head module 210 detects the relative positional relationship between the head modules 210 attached to the base frame 212, and based on the detection result, the interval between the head modules 210 falls within an allowable range. This is done by adjusting the mounting position in the X direction.

  Here, the relative positional relationship between the head modules 210 attached to the base frame 212 is detected by recording an image of a predetermined test pattern on a sheet with the inkjet head 200 to which the head module 210 is assembled. . That is, the inkjet head 200 with the head module 210 assembled is mounted on the inkjet recording apparatus 10, an image of a predetermined test pattern is recorded on the paper P, and the relative positional relationship of each head module 210 is determined from the recorded image. To detect.

  Reading of the image recorded on the paper P is performed by the inline sensor 58. The system controller 100 acquires the image data of the test pattern read by the in-line sensor 58, processes the obtained image data, and detects the relative positional relationship of each head module 210. For example, as shown in FIG. 14, the distance between dots ejected by the reference nozzle N in each head module 210 is measured on the image data, and the relative positional relationship (adjacent heads) of each head module 210 is measured. The interval δ) of the module 210 is detected. This process is performed by the system controller 100 executing a predetermined control program. The system controller 100 functions as position detection means and position information acquisition means for detecting the relative position of each head module 210 by executing this control program.

  After the relative positional relationship of each head module 210 is detected, the attachment position of each head module 210 is finely adjusted using the X direction attachment position adjusting means. That is, the position of each head module 210 in the X direction is adjusted so that the interval between adjacent head modules 210 is within a preset allowable range.

  The position adjustment in the X direction by the X direction attachment position adjusting means is performed by rotating the eccentric roller 248 provided in each head module 210. The eccentric roller 248 is rotated using a screw driver. That is, since a groove for a screw driver is formed on the end surface of the shaft portion 248A of the eccentric roller 248, the tip of the screw driver is fitted in the groove, and the shaft portion 248A is rotated by the screw driver. The eccentric roller 248 is rotated.

  When the shaft portion of the eccentric roller 248 is rotated, the eccentric roller 248 rotates eccentrically. When the eccentric roller 248 rotates eccentrically, the head module 210 moves in the X direction with reference to the X direction positioning reference pin 296.

  Here, when the head module 210 moves in the X direction, the amount of displacement is detected by the magnetic sensor 298. Information on the detected displacement amount is output to the system controller 100. The system controller 100 outputs information on the obtained displacement amount to the display unit 132. The operator rotates the eccentric roller 248 by a necessary amount based on the displacement amount information displayed on the display unit 132.

  The correction amount of each head module 210 is determined from the relative positional relationship of each head module 210. That is, the correction amount of the mounting position of each head module 210 is determined so that the interval between adjacent head modules 210 is within a preset allowable range.

  The system controller 100 acquires information on the relative position of each head module 210 (head module position information), and calculates a correction amount for keeping the interval between adjacent head modules 210 within an allowable range. Information on the calculated correction amount of the mounting position of each head module 210 is displayed on the display unit 132 as an instruction unit. The operator moves the head module 210 and adjusts the mounting position of the head module 210 based on the correction amount information displayed on the display unit 132.

  The correction amount is calculated when the system controller 100 executes a predetermined control program. By executing this control program, the system controller 100 functions as a correction amount calculating means.

  The mounting and position adjustment (positioning) of the head module 210 is completed by the series of operations described above. Here, the case where all the head modules 210 are attached to the base frame 212 has been described. However, when a part of the head modules 210 is replaced, the attachment is performed in the same procedure and the position is adjusted.

  The head module 210 is removed as follows.

  The head module 210 is attached in a state of being suspended by the base frame 212 while being locked to the locking bar 288 of the Z-direction hanging rod 278. First, the lock bar 288 is disengaged. That is, the Z-direction hanging rod 278 is rotated to move the lock bar 288 to the unlock position. As a result, the lock bar 288 is disengaged from the notches 258A and 258B, and the engagement between the head module 210 and the lock bar 288 is released. After the engagement between the head module 210 and the locking bar 288 is released, the head module 210 is pulled downward. As a result, the head module 210 is removed from the base frame 212. When the head module 210 is pulled down, the pair of Y-direction guide posts 276 serve as guides, so that the head module 210 can be removed without contacting the other head modules 210.

  As described above, according to the inkjet head 200 of the present embodiment, in the inkjet head 200 configured by connecting a plurality of head modules 210, each head module 210 is individually attached to the base frame 212, and individually. The mounting position is adjusted. Thereby, attachment and position alignment can be performed easily.

  Further, in the inkjet head 200 of the present embodiment, since the high-precision positioning using the eccentric roller 248 can be performed for the positioning in the X direction where high-precision positioning is required, the head module is highly accurate. You can connect each other. Further, the adjustment width can be sufficiently secured, and the component tolerance can be suppressed low. Thereby, manufacturing cost can be held down.

  In addition, the inkjet head 200 according to the present embodiment has a structure in which the head modules 210 are alternately attached to the base frame 212 when the head modules 210 are attached to the base frame 212. Thereby, the space | interval of the adjacent head module 210 can be taken widely. Since the distance between the adjacent head modules 210 can be widened, the distance between the positioning contacts (the distance between the head module Z-direction contact members 242) can be widened (print area width (total nozzle row). Can be taken wider than length).). Thereby, the precision of the rotation direction of the head module 210 can be taken high, and the head module 210 can be attached with high precision in a more stable state. For example, when the print area width l of the head module 210 is 40 mm, the distance between the contact points for positioning is 70 mm.

《Head module positioning method considering other heads》
As described above, the positioning of the head module 210 is performed by adjusting the mounting position of each head module 210 in the X direction so that the interval between the adjacent head modules 210 is within an allowable range.

  At this time, not only using the relative position information of the head module 210 of the inkjet head 200 to be adjusted, but also using the relative position information of the head module 210 of another inkjet head 200, By adjusting the mounting position of the head module 210 of each inkjet head 200, the head unit 56 as a whole can be positioned with higher accuracy.

  For example, each head module of each inkjet head 200 is set so that the interval between adjacent head modules 210 is within an allowable range based on information on the relative position of the head module 210 of each inkjet head 200 (head module position information). While adjusting the attachment position of 210, the attachment position of each head module 210 of each inkjet head 200 is adjusted so that the printing area width L of each inkjet head 200 may become the same. As a result, the print area width L of each inkjet head 200 matches, and a high-quality image can be recorded.

  The inkjet recording apparatus 10 according to the present embodiment ejects cyan (C) ink droplets, an inkjet head 200C that ejects magenta (M) ink droplets, and a yellow (Y) ink droplet. Ink jet head 200Y, and inkjet head 200K that ejects black (K) ink droplets, cyan ink jet head 200C, magenta ink jet head 200M, yellow ink jet head 200Y, and black ink jet Using the information on the relative position of the head module 210 of each head of the head 200K, the head modules 210 of the inkjet heads 200C, 200M, 200Y, and 200K are positioned.

  Here, the print area width L in each inkjet head 200 can be obtained from information on the relative position of the head module 210 as shown in FIG. 14, for example. That is, the print area width L of the inkjet head 200 can be obtained from the information of the print area width l of each head module 210 (the length of the nozzle row of the head module 210) and the information of the interval δ of each head module 210. (The print area width l of each head module 210 is known).

  Further, the position of each head module 210 in the head (for example, the head module disposed at one end of the inkjet head 200) from the information of the print area width l of each head module 210 and the information of the interval δ of each head module 210. The position of each head module 210 with respect to 210 can also be obtained.

  As described above, when adjusting the position of the head module 210 of each inkjet head 200, the adjacent heads are utilized using information on the relative position of the head module 210 of each inkjet head 200 (head module position information). The mounting position of each head module 210 of each inkjet head 200 is adjusted so that the interval between the modules 210 is within an allowable range and the print area width L of each inkjet head 200 is the same.

  Hereinafter, a specific procedure of this adjustment method will be described.

  First, the relative position of each head module 210 attached to the base frame 212 is detected (head module position information acquisition step).

  As described above, the relative position of each head module 210 attached to the base frame 212 is detected by recording an image of a predetermined test pattern on a sheet with the inkjet head 200 to which the head module 210 is assembled. Is called. That is, an image of a predetermined test pattern is recorded on the paper P, the image recorded on the paper P is read by the in-line sensor 58, the read image data is processed, and the relative of the head module 210 of each inkjet head 200 is processed. The correct position. This process is performed by the system controller 100 executing a predetermined control program. The system controller 100 functions as position detection means and position information acquisition means for detecting the relative position of each head module 210 by executing this control program.

  As will be described later, the system controller 100 also functions as a correction amount calculation unit by executing a predetermined control program. And the system controller 100 comprises the adjustment apparatus of the inkjet head 200 with the display part 132 as an instruction | indication means.

  After detecting the relative position of each head module 210, the mounting position of each head module 210 is adjusted using the X-direction mounting position adjusting means (position adjusting step). At this time, using the relative position information (head module position information) of the head module 210 of each inkjet head 200, the interval between the adjacent head modules 210 is within an allowable range, and printing of each inkjet head 200 is performed. The mounting position of each head module 210 of each inkjet head 200 is adjusted so that the region width L is the same.

  From the relative position information (head module position information) of the head module 210 of each inkjet head 200, the system controller 100 allows the interval between the adjacent head modules 210 to be within an allowable range, and the print area of each inkjet head 200. A correction amount of the attachment position of each inkjet head 200 for making the width L the same is calculated.

  In this case, for example, one reference head is determined, and the correction amount of the mounting position of the head module 210 of the remaining head is calculated so as to coincide with the print area width L of the head. For example, as shown in FIG. 15, when the black (K) inkjet head 200K is used as a reference, the print area width L (K) of the black (K) inkjet head 200K and the remaining inkjet heads 200C, 200M, and 200Y The correction amount of the mounting position of the head module 210 of each inkjet head 200C, 200M, 200Y is calculated so that the print area widths L (C), L (M), (Y) are the same.

  In addition, the correction amount of the mounting position of the head module 210 of each inkjet head 200 can be calculated so that the print area width L matches between adjacent heads.

  Information of the calculated correction amount of the mounting position of the head module 210 of each inkjet head 200 is displayed on the display unit 132 as an instruction unit. The operator moves the head module 210 and adjusts the mounting position of the head module 210 based on the correction amount information displayed on the display unit 132.

  The correction amount is calculated when the system controller 100 executes a predetermined control program. By executing this control program, the system controller 100 functions as a correction amount calculating means.

  As described above, when positioning the head module 210 of each inkjet head 200, the information of the relative position of the head module 210 of the inkjet head 200 to be adjusted is not used, but the heads of other inkjet heads 200 are used. By adjusting the mounting position of the head module 210 of each inkjet head 200 using information on the relative position of the module 210, the head unit 56 as a whole can be positioned with higher accuracy.

  In the above example, the mounting position of each head module 210 of each inkjet head 200 is such that the interval between adjacent head modules 210 is within an allowable range and the print area width L of each inkjet head 200 is the same. In addition, the mounting positions of the head modules 210 of the inkjet heads 200 are further adjusted so that the shift of registration (relative recording position relationship of dots) (so-called registration shift) is minimized. You may make it adjust. That is, the interval between adjacent head modules is within an allowable range, the print area width L of each inkjet head 200 is the same, and the registration deviation between the heads 200 is minimized. The mounting position of the head module 210 is adjusted.

  For example, in the example shown in FIG. 15, when the position of the second head module 210C2 of the cyan inkjet head 200C is adjusted, the interval between the first head module 210C1 and the third head module 210C3 located adjacent to each other is allowed. The second head module 210M2 of the magenta ink-jet head 200M, the second head module 210Y2 of the yellow ink-jet head 200Y, and the second head module 210K2 of the black ink-jet head 200K are adjusted. Adjust the position so that the registration gap is minimized. Further, the mounting position of the head module 210 of each inkjet head 200 is adjusted so that the print area width L is the same in each inkjet head 200C, 200M, 200Y, and 200K. As a result, it is possible to make it difficult to cause a shift between colors, and it is possible to record a higher quality image.

  In the above example, the case where the mounting position of the head module 210 of each inkjet head 200 is adjusted on the apparatus of the inkjet recording apparatus 10 has been described. However, the mounting position of the head module 210 may be adjusted outside the apparatus. it can.

<Monitoring the mounting position of the head module>
As described above, the head module 210 is positioned and attached to the base frame 212. However, when the head module 210 is used, the mounting position gradually shifts. If the use of the inkjet head 200 is continued in a state where the mounting position of the head module 210 is shifted, the quality of the image recorded on the paper P is degraded. Therefore, it is preferable to correct the mounting position of the head module 210 before the deviation exceeds the allowable range.

  On the other hand, in order to determine whether or not the mounting position of the head module 210 is shifted, it is necessary to monitor the mounting position of the head module 210. Hereinafter, a method for monitoring the mounting position of the head module 210 will be described.

<First example>
The inkjet head 200 according to the present embodiment includes a magnetic sensor 298 and a magnet 260 as means (position detection means) for detecting the mounting position of the head module 210. The magnetic sensor 298 detects the amount of displacement of the head module 210 and detects the mounting position. Therefore, the displacement of the mounting position of the head module 210 is monitored using the position detecting means comprising the magnetic sensor 298 and the magnet 260. This process is performed by the system controller 100 according to a predetermined control program.

  When the adjustment (positioning) of the mounting position of the head module 210 is completed, the system controller 100 acquires information on the displacement amount of the head module 210 from the magnetic sensor 298. Then, the obtained displacement information is recorded in the nonvolatile memory (storage means) 134 as initial position information.

  Thereafter, the system controller 100 acquires information on the displacement amount of the head module 210 from the magnetic sensor 298 at a preset detection timing. Then, the acquired displacement amount information is recorded in the nonvolatile memory 134. At the same time, the system controller (determination means) 100 calculates the amount of displacement from the initial position (position when adjusting the mounting position) as the amount of deviation. Then, the calculated deviation amount is compared with a threshold value. This threshold value is set as an allowable range of the displacement amount of the mounting position of the head module 210. If the system controller 100 determines that the amount of deviation is greater than or equal to the threshold, the system controller 100 determines that a positional deviation greater than the allowable amount has occurred in the head module 210.

  If it is determined that a positional shift exceeding the allowable level has occurred in the head module 210, the system controller 100 performs a predetermined warning operation. For example, a message prompting the position adjustment of the head module 210 is displayed on the display unit 132 as a warning unit. Alternatively, when an alarm means is provided, an alarm is issued, and when an alarm light is provided, the alarm light is turned on. The operator receives this warning and adjusts the head module 210.

  In this way, by monitoring the mounting position of the head module 210 and correcting the mounting position of the head module 210 before the deviation exceeds the allowable range, the inkjet head 200 can always be kept in the best state. Thereby, a high quality image can always be recorded.

  In the above example, when the adjustment (positioning) of the mounting position of the head module 210 is completed, the initial position is set. Timing for adjusting the mounting position of the head module 210 is as follows: when the inkjet head 200 is manufactured, when the head module 210 is replaced, when the inkjet recording apparatus 10 is started, when the inkjet head 200 is maintained, after the inkjet head 200 is transported ( For example, after shipment from a factory, etc., and before installation on the inkjet recording apparatus 10. Further, it may be performed every time a certain number of sheets are recorded, or may be performed every certain recording time (operating time). Further, it may be performed for each print job.

  Moreover, it is preferable to set the timing (detection timing) for detecting the position (displacement amount) before and after the situation in which the positional deviation of the head module 210 is likely to occur. For example, when a set number of print jobs are completed, when the inkjet recording apparatus 10 is started, or when maintenance is performed on the inkjet head 200 periodically (for cleaning to clean the nozzle surface of the inkjet head 200, etc.) Examples include when the inkjet head 200 is transported, when the inkjet head 200 is moved (for example, when the inkjet head 200 is moved to the maintenance unit for maintenance), and when the temperature is changed. As described above, by monitoring only before and after the situation in which the position change of the head module is likely to occur, the number of sensor operations can be reduced, and the life of the sensor can be extended.

  In the above example, a predetermined warning operation is performed when it is detected that a positional deviation exceeding the allowable range occurs in the head module 210. However, a positional deviation exceeding the allowable level is applied to the head module 210. The processing to be performed when it is determined that the occurrence has occurred is not limited to this. In addition, the image recording operation may be stopped, a mark indicating that a positional deviation has occurred with respect to the paper P, and the quality check of the portion printed by the head module 210 where the positional deviation has occurred may be strengthened. Good.

  In addition, when the positional deviation exceeding the allowable value occurs in the head module 210 as described above, unevenness of droplet ejection such as streaks and unevenness (so-called uneven connection) occurs at the joint portion, so that the ink can be corrected. May be controlled (joint unevenness correction). In other words, the system controller (discharge control means) 100 generates dot data from the image data, and creates dot data that corrects connection unevenness when generating the dot data. As a result, a high-quality image can be recorded even when the head module is misaligned.

  Further, as will be described later, when each head module 210 is provided with a driving unit for driving the X-direction mounting position adjusting unit (mounting position adjusting unit), the positional deviation may be automatically corrected. Good. Thereby, it is possible to always maintain a state in which there is no positional deviation (a state in which the positional deviation is within an allowable range).

<Second example>
The head module 210 and the base frame 212 are expanded and contracted by heat and deformed. Therefore, if the temperature of the environment when the head module 210 is positioned is different from the temperature in the actual use environment, the mounting position of the head module 210 is displaced. The degree of deviation caused by temperature change is determined by the material used and can be obtained in advance. Therefore, if the ambient temperature of the head module 210 is detected, the displacement amount of the mounting position can be detected (estimated). Hereinafter, a method for monitoring the mounting position of the head module 210 based on the ambient temperature of the head module 210 will be described.

  In this method, information on the ambient temperature of the head module 210 is required. Therefore, as shown in FIG. 16, the base frame 212 is provided with a temperature sensor 302 as temperature detecting means corresponding to the mounting position of each head module 210. For example, it is installed in the vicinity of the magnetic sensor 298.

  When the adjustment (positioning) of the mounting position of the head module 210 is completed, the system controller 100 acquires information on the ambient temperature of the head module 210 from the temperature sensor 302. Then, the obtained ambient temperature information is recorded in the nonvolatile memory (storage means) 134 as positioning temperature information.

  Thereafter, the system controller 100 acquires information on the ambient temperature of the head module 210 from the temperature sensor 302 at a preset detection timing. Then, the acquired information on the ambient temperature of the head module 210 is recorded in the nonvolatile memory 134. At the same time, the system controller 100 calculates a temperature difference from the temperature at the time of positioning. Then, the calculated temperature difference is compared with a threshold value. This threshold value is set as a temperature difference that causes a positional deviation that is greater than or equal to an allowable value. It is set as an allowable range of the deviation amount of the mounting position of the head module 210. If the system controller 100 determines that the temperature difference is equal to or greater than the threshold value, the system controller 100 determines that a positional deviation greater than an allowable value has occurred in the head module 210.

  If it is determined that a position misalignment head module 210 exceeding the allowable level has occurred, the system controller 100 performs a predetermined warning operation. The operator receives this warning and adjusts the head module 210.

  In the above example, when the adjustment (positioning) of the mounting position of the head module 210 is completed, the temperature at the time of position adjustment is detected. The timing for adjusting the mounting position of the head module 210 is the same as that when detecting the initial position, when the inkjet head 200 is manufactured, when the head module 210 is replaced, when the inkjet recording apparatus 10 is activated, On the other hand, during regular maintenance (when cleaning the nozzle surface, etc.), after transportation of the inkjet head 200 (for example, after transportation such as shipment from a factory), when mounted on the inkjet recording apparatus 10 ( For example, before or after mounting on the inkjet recording apparatus 10. Further, it may be performed for every fixed number of recording sheets, for every fixed recording time (operating time), or for each print job.

  Also, the timing for detecting the ambient temperature is preferably set before and after the situation in which the positional deviation of the head module 210 is likely to occur, similarly to the timing for detecting the position (displacement amount). For example, when a set number of print jobs are completed, when the inkjet recording apparatus 10 is started, when the inkjet head 200 is regularly maintained, when the inkjet head 200 is transported, when the head module 210 is moved, For example, when the temperature changes. As described above, by monitoring only before and after the situation in which the position change of the head module is likely to occur, the number of sensor operations can be reduced, and the life of the sensor can be extended.

  Further, the processing performed when it is determined that a positional deviation exceeding the permissible level has occurred in the head module 210 includes not only a warning operation, but also correction of joint unevenness, stop of the image recording operation, and positional deviation with respect to the paper P. You may make it perform the reinforcement | strengthening of the quality check of the part printed with the mark which shows that it generate | occur | produced, and the head module 210 which the position shift generate | occur | produced.

  Further, as will be described later, when each head module 210 is provided with a driving unit for driving the X-direction mounting position adjusting unit (mounting position adjusting unit), the positional deviation may be automatically corrected. Good. Thereby, it is possible to always maintain a state in which there is no positional deviation (a state in which the positional deviation is within an allowable range).

<Other examples>
In the above example, the displacement amount and the ambient temperature are separately detected. However, the displacement amount and the ambient temperature may be simultaneously detected and recorded in the memory. In this case, the displacement amount can be corrected using information on the ambient temperature. Thereby, a more accurate deviation amount can be detected.

  In addition, the inkjet head 200 of this example is configured to manually adjust the position in the X direction. However, in the case of a head (described later) provided with a driving unit for moving the head module 210 in the X direction. Alternatively, the position can be automatically adjusted.

  In the above example, the displacement amount information is recorded in the nonvolatile memory 134 provided in the ink jet recording apparatus 10. However, the head itself includes a memory, and the displacement information is stored in the memory provided in the head. May be recorded. In this case, the base frame 212 may be provided with a memory, or each head module 210 may be provided with a memory.

  Further, the displacement amount information recorded in the memory may be rewritten (updated configuration) every time the displacement amount is detected, or may be left as a history.

《Magnetic sensor sensitivity correction》
In the ink jet head 200 of the present embodiment, a position detection means for detecting the position of the head module 210 is constituted by a magnet 260 and a magnetic sensor 298.

  The magnet 260 is provided in the head module 210, and the magnetic sensor 298 is provided in the base frame 212. When the head module 210 is attached to the base frame 212, the magnet 260 and the magnetic sensor 298 are disposed to face each other, and the displacement amount of the head module 210 can be detected.

  By the way, the inkjet head 200 according to the present embodiment is configured by connecting a plurality of head modules 210 to the base frame 212 so as to be connected in a line. At this time, the order in which the head modules 210 are arranged can be arbitrarily determined. That is, since each head module 210 has the same structure, it can be attached at any position and can be arbitrarily replaced. For this reason, the combination of the magnetic sensor 298 and the magnet 260 is not uniquely determined.

  On the other hand, the value output from the magnetic sensor 298 when the head module 210 moves (movement in the X direction), that is, the sensitivity (gain) of the magnetic sensor 298 varies depending on the combination of the magnetic sensor 298 and the magnet 260. Factors that cause the sensitivity of the magnetic sensor 298 to fluctuate include individual differences in the output of the magnetic sensor 298, individual differences in the magnetic force of the magnet 260, and displacement of the mounting position of the magnetic sensor 298 and the magnet 260 (for example, in the Y direction or Z direction). Displacement). Therefore, even when the magnetic sensor 298 and the magnet 260 are used in any combination, if these pieces of information can be acquired, the sensitivity of the magnetic sensor 298 can be corrected and used with a constant sensitivity.

  Hereinafter, a method for correcting the sensitivity of the magnetic sensor 298 will be described.

  As shown in FIG. 17, the base frame 212 to which the magnetic sensor 298 is attached is provided with a magnetic sensor side memory (sensor side storage means) 310 for each magnetic sensor 298. Information (sensor side correction information) necessary for correcting the sensitivity of the magnetic sensor 298 provided with the magnetic sensor side memory 310 is recorded in the magnetic sensor side memory 310.

  On the other hand, each head module 210 to which the magnet 260 is attached is provided with a magnet side memory (detected body side storage means) 312. In the magnet-side memory 312, sensitivity correction information (detected body-side correction information) of the magnetic sensor 298 required when using the magnet 260 attached to the head module 210 is recorded.

  When the head module 210 is attached to the base frame 212, the system controller 100 as sensitivity correction means reads sensor side correction information from the magnetic sensor side memory 310. Also, the magnet side correction information is read from the magnet side memory 312 of the magnet 260 corresponding to the magnetic sensor 298 provided with the magnetic sensor side memory 310. Then, the sensitivity of the magnetic sensor 298 is corrected based on the read sensor side correction information and magnet side correction information.

  Thereby, even if it is a case where the magnetic sensor 298 and the magnet 260 are used by arbitrary combinations, the sensitivity of the magnetic sensor 298 can be used with constant.

  Here, as the sensor-side correction information, individual information of the output of the magnetic sensor 298 (individual data of detection sensitivity (gain)), information on the mounting position of the magnetic sensor 298, and the like are recorded. On the other hand, as the magnet side correction information, information on magnetic force as individual information of the magnet 260, information on the attachment position of the magnet 260, and the like are recorded.

  For example, when information on the mounting position of the magnetic sensor 298 is recorded as the sensor-side correction information and information on the mounting position of the magnet 260 is recorded as the magnet-side correction information, a shift in the mounting position between the magnetic sensor 298 and the magnet 260 is recorded. (Deviation amount and deviation direction) can be obtained. If the displacement of the mounting position between the magnetic sensor 298 and the magnet 260 is known, the amount of correction of the sensitivity of the magnetic sensor 298 can be known, so the system controller 100 can determine whether the mounting position between the magnetic sensor 298 and the magnet 260 is different. The sensitivity of the magnetic sensor 298 is corrected.

  Similarly, if the information of the individual information of the output of the magnetic sensor 298 is known, the output difference due to the individual difference can be corrected. Therefore, individual information of the magnetic sensor 298 (individual data of detection sensitivity (gain)) as the sensor-side correction information. Is recorded, the information is read and the sensitivity of the magnetic sensor 298 is corrected.

  Also, if the magnetic force of the magnet 260 is known, the sensitivity of the magnetic sensor 298 can be corrected according to the magnetic force of the magnet 260, so if the magnetic force information of the magnet 260 is recorded as the magnet side correction information, Information is read and the sensitivity of the magnetic sensor 298 is corrected.

  As described above, when the magnetic sensor 298 and the magnet 260 have information necessary for correcting the sensitivity of the magnetic sensor 298 individually, the magnetic sensor 298 and the magnet 260 are used in an arbitrary combination. Even so, the sensitivity of the magnetic sensor 298 can be corrected so as to have a constant sensitivity.

  The information recorded in the magnetic sensor side memory 310 and the magnet side memory 312 is not particularly limited as long as the information is effective for correcting the sensitivity of the magnetic sensor 298. In addition to the above, for example, information on the ambient temperature of the magnetic sensor 298 or the like can be recorded in the magnetic sensor side memory 310 as sensor side correction information. That is, in the magnetic sensor, the sensitivity of the sensor may vary or the mounting position may vary depending on the temperature, so information on the ambient temperature is recorded in the magnetic sensor side memory 310 as sensor side correction information. Thus, a change in sensitivity of the magnetic sensor 298 based on the temperature can be corrected. Similarly, since the magnetic force of the magnet 260 may change according to the temperature or the mounting position may change, the temperature of the magnet 260 can be changed by recording the ambient temperature information in the magnet side memory 312 as the magnet side correction information. The change in sensitivity of the magnetic sensor 298 based on the above can be corrected. Thereby, measurement with higher accuracy becomes possible.

  In addition, when the information on the ambient temperature of the magnetic sensor 298 is stored in the magnetic sensor side memory 310, a temperature sensor is separately provided in the vicinity of the magnetic sensor 298. The ambient temperature information may be recorded periodically at regular intervals, or may be set at a predetermined detection timing (for example, when a set number of print jobs are completed, when the inkjet recording apparatus 10 is started, The head 200 may be configured to detect and record during maintenance periodically performed, during transportation of the inkjet head 200, during movement of the inkjet head 200, and the like.

  Similarly, when information on the ambient temperature of the magnet 260 is stored in the magnet-side memory 312, a temperature sensor is separately provided in the vicinity of the magnet 260. The ambient temperature information may be recorded periodically at regular intervals, or may be detected and recorded at a preset detection timing.

  In addition, since the magnet 260 and the magnetic sensor 298 are disposed close to each other after the head module 210 is attached to the base frame 212, a common temperature sensor may be used. For example, as shown in FIG. 16, when the temperature sensor 302 for detecting the ambient temperature of the head module 210 is provided, information on the temperature sensor 302 is acquired, and the magnetic sensor side memory 310 and the magnet side are obtained. It can also be configured to store in the memory 312.

  In addition, when there is no bias in temperature distribution with one inkjet head 200, it is also possible to employ a configuration in which information about the ambient temperature of all the magnetic sensors 298 and magnets 260 is measured with one temperature sensor. Or it can also be set as the structure which divides | segments a measurement area | region into multiple and measures temperature for every area | region.

  In the above example, the magnetic sensor side memory 310 is prepared for each magnetic sensor 298. However, for the magnetic sensor 298, one magnetic sensor side memory 310 is prepared, and each magnetic sensor side memory 310 is provided with each magnetic sensor side memory 310. The sensor-side correction information of the magnetic sensor 298 may be recorded so as to be identifiable.

  Alternatively, one management table may be prepared, and sensor-side correction information for each magnetic sensor 298 and magnet-side correction information for each magnet 260 may be recorded in this management table. In this case, each of the magnetic sensor 298 and the magnet 260 is given unique identification information (for example, a barcode or a two-dimensional barcode), and the identification information is read, and the corresponding sensor side correction information and magnet side correction information are read. Are read from the management table and used.

  Further, the sensor side correction information and the magnet side correction information may be recorded and read on a bar code or a two-dimensional bar code.

  In the above example, the system controller 100 performs the correction process of the sensitivity of the magnetic sensor 298 (the system controller 100 functions as a sensitivity correction unit by executing a predetermined control program). The inkjet head 200 may be equipped with a microcomputer as sensitivity correction means, and the microcomputer may be configured to perform sensitivity correction processing of the magnetic sensor 298.

<< Other examples of position detecting means >>
In the above embodiment, the position detection means for detecting the position of the head module 210 is constituted by the magnetic sensor 298 and the magnet 260, but the structure of the position detection means is not limited to this. In addition, the position detecting means can be configured using a configuration of a laser distance sensor, an infrared distance sensor, an eddy current sensor, or the like.

<Laser distance sensor>
When using a laser distance sensor, for example, a laser distance sensor is provided on the base frame 212 side, and a detected portion (laser irradiation part) of the laser distance sensor is provided on the head module 210 side.

  When using a laser distance sensor, it is preferable to perform sensitivity correction of the sensor as in the case of the magnetic sensor. That is, the laser distance sensor also has individual differences in the sensor output in the same manner as the magnetic sensor. Therefore, each sensor has a memory (sensor side storage means) and information for correcting the sensitivity in the memory (sensor side correction information). ) Is stored. For example, individual information (individual data of detection sensitivity (gain)) of the laser distance sensor, information on the mounting position, and the like are stored as sensor-side correction information. Similarly, the sensitivity of the sensor fluctuates depending on the reflectance, ambient brightness, ambient temperature, etc. on the detected part side, so the detected part side also has a memory (detected object side storage means), and the detected part is The correction information (detected body side correction information) of the sensitivity of the laser distance sensor necessary for detection by use is stored. For example, the reflectance of the detected portion, the ambient brightness, the ambient temperature, the information on the mounting position, and the like are stored as the detected object side correction information. Thereby, even if it is a case where any combination of a laser distance sensor and a to-be-detected part is used, it can correct and use so that it may become fixed sensitivity.

<Infrared distance sensor>
When using an infrared distance sensor, for example, an infrared distance sensor is provided on the base frame 212 side, and a detected portion (infrared irradiation part) of the infrared distance sensor is provided on the head module 210 side.

  When using an infrared distance sensor, it is preferable to perform sensitivity correction of the sensor as in the case of the magnetic sensor. That is, the infrared distance sensor also has an individual difference in the output of the sensor as in the case of the magnetic sensor. Therefore, each sensor has a memory (sensor side storage means) and information for correcting the sensitivity in the memory (sensor side correction information). ) Is stored. For example, individual information of the infrared distance sensor (individual data of detection sensitivity (gain)), information on the mounting position, and the like are stored as sensor-side correction information. Similarly, the sensitivity of the sensor varies depending on the reflectance, ambient temperature, temperature of the detected object, color of the detected object, brightness of the detected object, etc. Storage means) and the sensitivity correction information (detected body side correction information) of the infrared distance sensor necessary for detection using the detected portion is stored. For example, the reflectance of the detected part, the ambient temperature, the temperature of the detected object, the color of the detected object, the ambient brightness, the information on the mounting position, and the like are stored as the detected object side correction information. Thereby, even if it is a case where any combination of infrared distance sensors and a to-be-detected part are used, it can correct and use so that it may become fixed sensitivity.

<Eddy current sensor>
When using an eddy current sensor, for example, an eddy current sensor is provided on the base frame 212 side, and a detected portion of the eddy current sensor is provided on the head module 210 side.

  Even when an eddy current sensor is used, it is preferable to correct the sensitivity of the sensor as in the case of the magnetic sensor. That is, the eddy current sensor has individual differences in the sensor output in the same way as the magnetic sensor, so each sensor has a memory (sensor side storage means) and information for correcting the sensitivity in the memory (sensor side correction information). ) Is stored. For example, individual information of the eddy current sensor (individual data of detection sensitivity (gain)) and information on the mounting position are stored as sensor-side correction information. Similarly, since the sensitivity of the sensor fluctuates depending on the conductivity, magnetic permeability, temperature of the detected object, etc. on the detected part side, the detected part side also has a memory (detected object side storage means) and the detected part The correction information (detected body side correction information) of the sensitivity of the eddy current sensor necessary for the detection using is stored. For example, the conductivity and magnetic permeability of the detected part, the temperature of the detected object, information on the mounting position, and the like are stored as detected object side correction information. As a result, even if any combination of eddy current sensors and detected parts are used, they can be modified and used so as to have a constant sensitivity.

<Others>
In addition, the displacement detection means for detecting the displacement amount of the head module 210 has a high resolution, and a small measuring device can be suitably used.

<< Other examples of X direction mounting position adjusting means >>
The X direction mounting position adjusting means (mounting position adjusting means) of the above embodiment is configured to manually rotate the eccentric roller 248, but as shown in FIG. 18, the driving means is mounted on the head module 210. And it can also be set as the structure rotated automatically.

  In the example shown in FIG. 18, a motor 320 is mounted on the head module 210 as a driving means for the eccentric roller 248. A screw gear (worm) 322 is connected to the drive shaft of the motor 320. A helical gear (worm wheel) 324 is coupled to the eccentric roller 248 to the shaft portion 248A. The screw gear 322 is meshed with the helical gear 324. When the motor 320 is driven to rotate the screw gear 322, the helical gear 324 rotates, and as a result, the eccentric roller 248 rotates. In this case, the shaft portion 248A of the eccentric roller 248 is formed in a columnar shape instead of a male screw, and the eccentric roller mounting hole 252 is formed as a through hole instead of a screw hole.

  Thus, the eccentric roller 248 can be configured to automatically rotate. In this case, the positioning process of the head module 210 can be automatically performed. Further, the correction process can be automatically performed even when the positional deviation beyond the allowable level occurs in the head module 210.

  In the above embodiment, the eccentric roller 248, the plunger 250, and the X-direction positioning reference pin 296 constitute the X-direction mounting position adjusting means, but the configuration of the X-direction mounting position adjusting means is limited to this. Is not to be done. In addition, for example, a moving mechanism such as a ball screw mechanism can be used.

<< Other examples of head module positioning methods >>
As described above, after the head module 210 is attached to the base frame 212, position adjustment (positioning) is performed.

  It can be determined from the relative positional relationship of each head module 210 which head module 210 is displaced (moved) to what extent it can be attached at an accurate position.

  Therefore, by providing an indicator indicating the necessary correction amount for each head module 210 and adjusting the position of the head module 210 based on the display of the indicator, the position of the head module 210 can be adjusted more easily.

  FIG. 19 is a diagram illustrating an example in which the position of the head module is adjusted based on the indicator display.

  As shown in the figure, the head module 210 is provided with an indicator (instruction means) 330 indicating a correction amount required. Indicator 330 is installed in a holder (not shown) in which inkjet head 200 is mounted, for example. The indicator 330 is provided for each head module 210.

  The indicator 330 shown in the figure is configured to display minus (−), zero (0), and plus (+) with a lamp (LED (Light Emitting Diode)). In this indicator 330, a lamp in a direction that requires correction is turned on. For example, when correction is necessary in the minus direction, a minus (−) lamp is lit, and when correction is necessary in the plus direction, a plus (+) lamp is lit. If no correction is necessary, the zero (0) lamp is lit.

  For example, when a minus (−) lamp is lit, the operator displaces the head module 210 in the minus direction. The system controller 100 acquires the displacement information of the head module 210 output from the magnetic sensor 298, and turns on the zero (0) lamp when the necessary amount is corrected. On the other hand, if the correction is made more than necessary, the plus (+) lamp is turned on. In this case, the operator displaces the head module 210 in the plus direction.

  In this way, by adjusting the position of the head module 210 using the indicator 330, the position can be adjusted in a convenient manner.

<< Other Embodiments >>
In the above embodiment, when the head module 210 is positioned in the Y direction, the head module Y direction fixed contact member 234 and the head module Y direction movable contact member 236 provided on the head module side are provided on the base frame side. The fixed contact base frame Y-direction positioning member 290 and the movable contact base frame Y-direction positioning member 292 are positioned to contact each other, but the mounting position is adjusted using an eccentric roller in the same manner as the X-direction positioning. It is good also as a structure adjusted with a means. The same applies to the Z direction.

  As in the above embodiment, the head module Y direction fixed contact member 234 and the head module Y direction movable contact member 236 provided on the head module side are fixed contact base frame Y direction provided on the base frame side. When positioning in the Y direction by contacting the positioning member 290 and the movable contact base frame Y direction positioning member 292, the head module Y direction movable contact member 236 in advance so that the head module 210 is correctly attached in the Y direction. It is preferable to adjust the position. The same applies to the Z direction, and it is preferable to adjust the position of the head module Z direction contact member 242 in advance. For example, it is preferably performed at the time of factory shipment.

  In the above embodiment, the eccentric roller 248 and the plunger 250 are provided on the head module 210 side, and the X-direction positioning reference pin 296 is provided on the base frame 212 side, but the eccentric roller 248 and the plunger 250 are provided. A configuration may be adopted in which the X-direction positioning reference pin 296 is provided on the head module 210 side provided on the base frame 212 side.

  In the above embodiment, the magnetic sensor 298 is provided on the base frame 212 side and the magnet 260 is provided on the head module 210 side. However, the magnetic sensor 298 is provided on the head module 210 side, and the magnet 260 is provided on the base frame 212 side. It can also be set as the structure provided in the side.

  In the above embodiment, as the eccentric roller 248, a roller having a configuration in which the roller portion 248B and the shaft portion 248A are eccentric is used. However, when the roller portion is a roller having an elliptical shape or the like. Even if it exists, the same effect can be acquired.

  In the above embodiment, when the relative positional relationship between the head modules is detected, the test pattern is read by the inline sensor 58 mounted on the ink jet recording apparatus 10, but the image reading means (external image reading means ( It is also possible to read the test pattern image with a scanner or the like and detect the relative positional relationship between the head modules.

  DESCRIPTION OF SYMBOLS 10 ... Inkjet recording apparatus, 12 ... Paper feed part, 14 ... Processing liquid application part, 16 ... Processing liquid drying process part, 18 ... Image recording part, 20 ... Ink drying process part, 22 ... Ultraviolet irradiation part, 24 ... Paper discharge 30 ... Paper feed base, 32 ... Soccer device, 32A ... Suction foot, 34 ... Feed roller pair, 34A ... Roller, 34B ... Roller, 36 ... Feeder board, 36A ... Tape feeder, 36B ... Retainer, 36C ... Colo , 38 ... front application, 40 ... paper feed drum, 40A ... gripper, 42 ... treatment liquid application drum, 42A ... gripper, 44 ... treatment liquid application device, 46 ... treatment liquid drying treatment drum, 46A ... gripper, 48 ... paper conveyance Guide, 50 ... processing liquid drying processing unit, 52 ... image recording drum, 54 ... paper pressing roller, 56 ... head unit, 58 ... in-line sensor, 59 ... contact Prevention plate, 60 ... mist filter, 62 ... drum cooling unit, 62A ... duct, 64 ... chain gripper, 64A ... first sprocket, 64B ... second sprocket, 64C ... chain, 64D ... gripper, 66 ... back tension applying mechanism, 68 ... Ink drying processing unit, 70A ... First horizontal transport path, 70B ... Inclined transport path, 70C ... Second horizontal transport path, 72 ... Guide plate, 74 ... Ultraviolet irradiation unit, 76 ... Discharge stand, 100 ... System controller DESCRIPTION OF SYMBOLS 102 ... Communication part 104 ... Image memory 110 ... Conveyance control part 112 ... Paper feed control part 114 ... Processing liquid application control part 116 ... Processing liquid drying control part 118 ... Image recording control part 120 ... Ink Drying control unit 122 ... UV irradiation control unit 124 ... Discharge control unit 130 ... Operation unit 132 ... Display 134 ... Non-volatile memory, 200 (200C, 200M, 200Y, 200K) ... Head, 210 ... Head module, 212 ... Base frame, 214 ... Head, 216 ... Bracket, 218 ... Head body, 220 ... Electrical / Piping 222 ... Nozzle surface, 222A ... Nozzle formation region, 224 ... Horizontal part, 224A ... Opening part, 226 ... Vertical part, 226A ... Vertical part body, 226B ... First overhang part, 226C ... Second overhang part, 234 ... head module Y direction fixed contact member, 236 ... one head module Y direction movable contact member, 238 ... head module Y direction movable contact member insertion hole, 240 ... head module Y direction movable contact member position adjusting screw, 242 ... head module Z direction contact member, 244... Head module Z direction contact member insertion hole, 246 ... head module Z direction contact member position adjusting screw, 248 ... eccentric roller, 248A ... shaft portion, 248B ... roller portion, 250 ... plunger, 252 ... eccentric roller mounting hole, 254 ... leaf spring, 256 ... guide groove, 256A ... enlarged diameter part, 258A ... notch part, 258B ... notch part, 260 ... magnet, 270 ... upper frame part, 272A ... lower frame part (first lower frame part), 272B ... lower frame part (second lower frame) 276 ... Y direction guide post, 276A ... flange portion, 278 ... Z direction hanging rod, 278A ... knob portion, 280 ... Y direction pressing plate, 282 ... Y direction pressing spring, 284 ... Z direction hanging rod insertion Hole, 286 ... Z direction pressing spring, 288 ... Lock bar, 290 ... Base frame Y direction positioning member for fixed contact, 292 ... Movable Base frame Y-direction positioning member, 294 ... Base frame Z-direction contact member, 296 ... X-direction positioning reference pin, 298 ... Magnetic sensor, 300 ... Magnetic sensor mounting portion, 302 ... Temperature sensor, 310 ... Magnetic sensor side memory, 312 ... Magnet side memory, 320 ... Motor, 322 ... Screw gear, 324 ... Helical gear, 330 ... Indicator, P ... Paper, N ... Nozzle

Claims (11)

A droplet discharge head configured by connecting a plurality of head modules, wherein each of the head modules is attached to a base frame and connected;
An attachment position adjusting means for individually adjusting the attachment position of each of the head modules attached to the base frame;
Position detecting means for detecting the position of each head module attached to the base frame at a preset detection timing;
Storage means for storing information on the position of each head module detected by the position detection means;
A droplet discharge device comprising:   The liquid droplet ejection apparatus according to claim 1, further comprising: a determination unit that determines whether or not the head module has a positional shift that is greater than or equal to an allowable amount based on information on a position of each head module stored in the storage unit.   The droplet discharge device according to claim 2, further comprising a warning unit that issues a warning when an unacceptable positional deviation occurs in the head module. Driving means for driving the attachment position adjusting means;
Position correcting means for controlling the drive of the driving means to correct the mounting position of the head module when a positional deviation more than allowable occurs in the head module;
The droplet discharge device according to claim 2, further comprising: Further comprising discharge control means for controlling the discharge of droplets from each of the head modules;
The ejection control means is configured so that each of the head modules is configured so as to correct unevenness in droplet ejection generated at a joint of the head modules due to the positional deviation exceeding the allowable range when the positional deviation exceeds the allowable level in the head module. The droplet discharge device according to claim 2, wherein the droplet discharge is controlled.   6. The detection timing is at least one of when the apparatus is activated, when the droplet discharge head is cleaned, when the droplet discharge head is transported, when the droplet discharge head is moved, and when the temperature changes. The droplet discharge device according to any one of the above.   7. The liquid droplet ejection apparatus according to claim 1, wherein the position detecting unit detects a position of the head module by detecting a displacement amount of the head module attached to the base frame. 8.   The liquid droplet ejection apparatus according to claim 7, wherein the position detection unit includes a magnet provided on one of the base frame and the head module and a magnetic sensor provided on the other.   The liquid droplet ejection apparatus according to claim 7, wherein the position detection unit detects a displacement temperature of the head module by detecting an ambient temperature of the head module attached to the base frame. A droplet discharge head configured by connecting a plurality of head modules, wherein each of the head modules is attached to a base frame and connected;
An attachment position adjusting means for individually adjusting the attachment position of each of the head modules attached to the base frame;
Temperature detecting means for detecting the ambient temperature of the head module attached to the base frame at a preset detection timing;
Storage means for storing information on the ambient temperature of the head module detected by the temperature detection means;
A droplet discharge device comprising:   The mounting position adjusting means biases the head module in a direction of adjusting the position of the head module, a positioning reference pin provided on one of the base frame and the head module, an eccentric roller provided on the other, and the head module. Biasing means for pressing and contacting the eccentric roller to the positioning reference pin, and rotating the eccentric roller pressed and contacting the positioning reference pin to position the head module at the position of the head module. The droplet discharge device according to claim 1, wherein the droplet discharge device is moved in the adjustment direction.

Images