JP5420459B2 - Coating apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a coating apparatus and an image forming apparatus, and more particularly to a roller support structure in a coating apparatus to which a roller coating method is applied.

  2. Description of the Related Art Conventionally, as a general-purpose image forming apparatus, an ink jet recording apparatus that forms a desired image on a recording medium by discharging color ink from a nozzle of an ink jet head is known.

  In order to perform high-definition image formation, an inkjet recording apparatus has been proposed in which ink is ejected after an aggregation treatment liquid for aggregating or insolubilizing ink is applied to a recording medium before drawing. By applying this two-component aggregation method, it is possible to achieve favorable image formation that does not cause blurring or color misregistration when not only paper media but also non- (hard) permeable media such as resin sheets and metal sheets are used. Is possible.

  As a method for uniformly applying the aggregation treatment liquid over the entire surface of the recording medium (on a relatively wide area of the recording medium), a roller application method using an application roller is preferably used. The roller coating method can apply a large amount of coating liquid onto a recording medium without depending on the physical properties of the coating liquid (here, the aggregating treatment liquid), and also has a uniform coating liquid layer. Can be formed on a recording medium.

  Patent Document 1 discloses an ink jet printer in which a paper optimizing device (heat-pressure fusion device) is installed upstream of a print head. Such a fusing device has a heating roll and a roll, and is configured such that a load F is applied to the nip by ordinary means.

  Patent Document 2 discloses an image forming apparatus having application means for applying a transparent liquid that insolubilizes a dye in ink. The application unit provided in the image forming apparatus includes an application roller that contacts the print material and applies the liquid to the print material, a supply roller that supplies the liquid to the application roller, and a liquid pumped up by the supply roller And a replenishment tank in which is stored.

  Patent Document 3 discloses an image recording apparatus including a processing liquid application unit having a coating roller, a counter roller, a coating liquid supply roller, a film thickness control roller, and a storage tank for storing the coating liquid. The treatment liquid application unit is configured such that a film thickness control roller is disposed between the application roller and the application liquid supply roller so that the application liquid supply roller is not separated from the application roller even when the application liquid is not applied. .

JP-A-11-320867 JP-A-8-72227 JP 2007-130942 A

  However, in the method of supplying a constant amount of coating liquid measured by the supply (metering) roller to the coating roller, when the coating liquid is supplied to the coating roller when coating is not performed, the coating roller applies the coating liquid to the recording medium. The amount of liquid at the time of the next application increases due to the influence of the return liquid that has not been performed. Therefore, it is preferable to configure so that the application liquid is not supplied to the application roller by separating the metering roller from the application roller when application is not performed.

  On the other hand, if the supply roller is separated from the application roller, the nip pressure of the application roller with respect to the recording medium may decrease. When such a decrease in the nip pressure occurs in the coating roller during coating, there is a concern about the occurrence of coating unevenness.

  The inventions disclosed in Patent Documents 1 to 3 do not focus on the problem of a decrease in the nip pressure of the application roller with respect to the recording medium when the supply roller is separated from the application roller in the roller application method. That is, Patent Documents 1 to 3 do not disclose a technique for solving such a problem.

  SUMMARY An advantage of some aspects of the invention is that it provides a coating apparatus and an image forming apparatus that can suppress a decrease in nip pressure with respect to a medium to be coated by a coating roller in a roller coating method and can realize preferable liquid coating. The purpose is to do.

In order to achieve the above object, a coating apparatus according to the present invention has a cylindrical shape, a pressure drum that conveys a medium held on a circumferential surface along a circumferential direction, and is held on a circumferential surface of the pressure drum. An application roller for applying a liquid to the medium, an application roller urging portion for urging the application roller against the circumferential surface of the impression cylinder, a separation mechanism for separating the application roller from the circumferential surface of the impression cylinder, The application roller support unit that supports the application roller in a swingable manner, the supply roller that supplies a predetermined amount of liquid to the application roller, and the contact and separation between the supply roller and the application roller are switched. A moving means for moving the supply roller; and a supply roller urging portion for urging the supply roller to the application roller, the moving means supporting the supply roller in a swingable manner. The supply roller support A supply roller oscillating cam that moves a portion in accordance with a predetermined cam curve, and a supply roller oscillating gear that is configured integrally with the supply roller oscillating cam and whose rotation shaft is supported by the application roller support part. the rotation axis of the rotary shaft and the supply roller swing gear of the feed roller swing cam is to have the structure that is supported by the application roller support portion, the supply roller biasing unit, the coating roller support portion An elastic member having a structure in which one end is fixed and the other end is fixed to the supply roller support portion is included .

  According to the present invention, the moving means for moving the supply roller includes a supply roller support portion that supports the supply roller in a swingable manner, and a supply roller swing cam that moves the supply roller support portion according to a predetermined cam curve, Since the rotation shaft of the supply roller swing cam and the rotation shaft of the supply roller swing gear configured integrally with the supply roller swing cam are configured to be supported by the application roller support portion, the supply roller is removed from the application roller. The contact pressure of the application roller with respect to the medium to be applied does not decrease due to the movement of the supply roller during separation, and the contact pressure of the supply roller with respect to the application roller decreases when the application roller is separated from the impression cylinder. There is nothing to do.

1 is an overall configuration diagram of a coating apparatus according to a first embodiment of the present invention. Enlarged view of the liquid applicator shown in FIG. The figure explaining the state at the time of paper delivery in the coating device shown in FIG. The figure explaining the state at the time of an anilox separation motor starting in the coating device shown in FIG. The figure explaining the state at the time of the nip start of the anilox roller in the coating device shown in FIG. The figure explaining the state at the time of the nip start of the coating roller in the coating device shown in FIG. The figure explaining the state at the time of the separation start of the anilox roller in the coating device shown in FIG. The figure explaining the problem in the separation state of an anilox roller The figure explaining the problem in the separation state of an anilox roller The schematic diagram which shows the separation state of the anilox roller in the coating device shown in FIG. Overall configuration diagram of a coating apparatus according to a second embodiment of the present invention 1 is an overall configuration diagram of an ink jet recording apparatus to which a coating apparatus according to the present invention is applied. The block diagram which shows the structure of the control system of the inkjet recording device shown in FIG.

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

[First Embodiment]
(Overall configuration of coating device)
FIG. 1 is an overall configuration diagram showing a schematic configuration of a coating apparatus according to a first embodiment of the present invention. The coating apparatus 10 shown in FIG. 1 includes a pressure drum 12 that supports a medium (not shown in FIG. 1; indicated by reference numeral 60 in FIGS. An application roller 14 that applies an application liquid to a medium supported on the peripheral surface of the cylinder 12 and an application unit 16 that includes a cam follower 15 (described in detail later) are included. The impression cylinder 12 is rotatably supported by the frame 18, and its rotation shaft is connected to a motor (not shown) via a transmission mechanism (not shown). The motor serves as a drive source for rotating the impression cylinder 12 in a predetermined direction (counterclockwise direction in the figure). The transmission mechanism disposed between the impression cylinder 12 and the motor may include a gear (reduction gear).

  The impression cylinder 12 includes a gripper 20 that sandwiches the leading end of the medium supported on the peripheral surface, a gripper operating mechanism 22 that opens and closes the gripper 20, a cam portion 24 that is provided corresponding to the position where the gripper 20 is disposed, It has. The gripper 20 protrudes from the peripheral surface of the impression cylinder 12 with the medium added, and the coating roller 14 is moved to avoid collision with the coating roller 14 when the gripper 20 passes the position where the coating roller 14 is disposed. A cam portion 24 is provided as a mechanism for separating from the impression cylinder 12. The separation of the application roller 14 will be described later.

  The application unit 16 is supported by the frame 18 so that the normal direction of the impression cylinder 12 at the contact position between the application roller 14 and the impression cylinder 12 (medium) is at a position of about 45 ° with respect to the horizontal plane. Such an arrangement prevents the peripheral surface of the impression cylinder 12 and the medium to be applied from being soiled even when the application liquid falls from the application roller 14.

  The medium fed by the paper feeding unit 26 is transferred to the peripheral surface of the impression cylinder 12 via the transfer cylinder 28, and the leading end is sandwiched by the gripper 20. When the medium supported on the peripheral surface of the impression cylinder 12 reaches the processing region of the application unit 16, a predetermined coating solution is applied to the surface (application surface) of the medium. The gripper 20 is provided at each of two symmetrical positions across the rotation axis of the impression cylinder 12, and the impression cylinder 12 has two medium support areas.

  FIG. 2 is an enlarged view of the application unit 16 illustrated in FIG. 1. The application unit 16 shown in the figure includes an application roller 14, an anilox roller 30 that supplies the application liquid to the application roller 14, and an application tray 32 that stores the application liquid. A supply pipe 34 and a discharge pipe 36 are connected to the application tray 32, and the application liquid is replenished from the supply tank (not shown) via the supply pipe 34, and the application liquid is supplied to the discharge tank (not shown) via the discharge pipe 36. Discharged.

  The application roller 14 has a structure in which a core metal that becomes the rotation shaft 14A is inserted into a hollow rubber roller, and bearings (not shown) that rotatably support the rotation shaft 14A are provided at both ends of the rubber roller. The rotation shaft 14A of the application roller 14 is supported by the application roller swing arm 38 so as to be swingable with the rotation shaft 30A of the anilox roller 30 as a swing support shaft, and is not connected via a transmission mechanism such as a gear. It is connected to the illustrated motor. When the motor is rotated at a predetermined rotation speed, the rubber roller that contacts the medium to be coated rotates in a predetermined rotation direction (clockwise direction in the drawing) at a predetermined rotation speed together with the rotating shaft 14A.

  The application roller oscillating arm 38 is fixed with a hook provided at one end of an application roller nip spring (not shown in FIG. 2; indicated by reference numeral 62 in FIGS. 8 to 10). A hook provided at the other end of the spring is fixed to a side plate 40 supported by the frame 18 (see FIG. 1). The application roller nip spring functions as an application roller urging unit that urges the application roller 14 to the pressure drum 12 so as to nip the application roller 14 to the peripheral surface of the pressure drum 12 with a predetermined nip pressure (contact pressure). doing.

  In FIG. 2, only the rear side plate 40 is illustrated, but a side plate similar to the side plate 40 is also provided on the front side in the drawing. That is, the application unit 16 has a structure that is supported from both sides by the side plate on the near side in the drawing and the side plate 40 on the back side in the drawing.

  As described above, when the cam follower 15 rides on the cam portion 24 (see FIG. 1) provided in the impression cylinder 12 in order to avoid contact between the application roller 14 and the gripper 20, the application roller 14 becomes the anilox roller. The rotary shaft 30A is supported so as to swing around the rotating shaft 30A. That is, the application roller swing arm 38 is supported so as to be swingable (rotatable) about the rotation shaft 30A of the anilox roller 30, and when the cam follower 15 of the application roller 14 rides on the cam portion 24 of the impression cylinder 12, The application roller swing arm 38 rotates in the clockwise direction in the drawing, and elastically deforms the application roller nip spring so as to contract.

  When the impression cylinder 12 further rotates and the application roller 14 lands on the peripheral surface of the impression cylinder 12, the application roller swing arm 38 rotates counterclockwise in the figure by the restoring force of the application roller nip spring, and the impression cylinder is rotated. The application roller 14 is urged against the 12 peripheral surfaces.

  The anilox roller 30 has a structure in which small holes called cells are regularly arranged on the surface of a metal cylinder plated (coated) with chromium or ceramics, and the coating liquid is held in the cells. A rotating shaft 30A of the anilox roller 30 is connected to a motor (not shown) via a transmission mechanism (not shown), and rotates in the counterclockwise direction in the figure when the motor is rotated.

  The anilox roller 30 is supported so that about half of the lower side in the figure is immersed in the coating liquid stored in the coating dish 32, and draws a certain amount of coating liquid from the coating dish 32 while rotating. The coating liquid pumped up by the anilox roller 30 is supplied to the coating roller 14 during a period in which the anilox roller 30 is nipped from the coating roller 14. That is, the anilox roller 30 is rotated in accordance with the coating amount of the coating solution, and a predetermined amount of coating solution is pumped up from the coating plate 32, and the fixed amount of coating solution is supplied to the coating roller 14.

  An anilox swinging arm 42 having one end connected to the rotating shaft 30A of the anilox roller 30 has a hook on one end side of the anilox nip spring 44 fixed to the other end. Is also supported so as to be rotatable about the anilox swinging fulcrum 46 located in the lower part. The hook on the other end side of the anilox nip spring 44 is fixed at a position above the anilox swing arm 42 of the application roller swing arm 38.

  The anilox oscillating arm 42 is pulled upward by the anilox nip spring 44 and rotates counterclockwise in the drawing so as to move the anilox roller 30 horizontally toward the application roller 14, thereby making the anilox relative to the application roller 14. The roller 30 is nipped. That is, the anilox nip spring 44 functions as an anilox roller (supply roller) urging unit that urges the application roller 14 to nip the anilox roller 30.

  The other end of the anilox swing arm 42 is configured to move up and down along a predetermined cam curve determined by the anilox swing cam 48. The anilox rocking cam 48 has a structure integrally formed with the anilox rocking gear 50, the anilox rocking gear 50 is engaged with the anilox rocking drive gear 52, and the anilox rocking drive gear 52 is interposed via the idler gear 54. The anilox swinging motor 56 is coupled.

  When the anilox swinging motor 56 is rotated, the anilox swinging cam 48 rotates counterclockwise in the drawing via the idler gear 54 and the anilox swinging drive gear 52, and pushes down the anilox swinging arm 42 downward. Then, the anilox roller 30 that is in contact with the application roller 14 moves horizontally in the direction opposite to the application roller 14 and is separated from the application roller 14.

(Explanation of anilox contact and separation control)
Next, nip (contact) and separation control between the application roller 14 and the anilox roller 30 in the above-described application apparatus 10 will be described. In the following description, parts that are the same as or similar to those described above are denoted by common reference numerals, and description thereof is omitted.

  The coating apparatus 10 shown in this example is configured to supply only a necessary amount of coating liquid to the coating roller 14 in order to make the thickness of the coating liquid applied to the medium constant (uniform). That is, the anilox roller 30 is nipped to the application roller 14 corresponding to the application start position of the application roller 14, and when a predetermined amount of application liquid is supplied to the application roller 14, the anilox roller 30 is separated from the application roller 14. In addition, the contact and separation between the application roller 14 and the anilox roller 30 are controlled.

  FIG. 3 schematically shows a state in which the medium 60 is transferred from the transfer cylinder 28 to the impression cylinder 12. At the time of delivery of the medium shown in the figure, the front end portion of the medium 60 is held by the gripper 20, the anilox roller 30 is separated from the application roller 14, and the anilox roller 30 stops rotating.

  FIG. 4 schematically shows a state at the start of the operation of the anilox swinging motor 56. When the anilox swinging motor 56 (see FIG. 2) is operated, the anilox roller 30 moves from the separated state shown in FIG. 3 to the application roller 14 side and is nipped with respect to the application roller 14 with a predetermined nip pressure. When the anilox roller 30 is nipped with respect to the application roller 14, the anilox swinging motor 56 is stopped, and the nip of the anilox roller 30 with respect to the application roller 14 is maintained.

  FIG. 5 schematically shows a state when the anilox swinging motor 56 is stopped and the anilox roller 30 starts to nip the application roller 14. The state shown in the figure is the time until the application start position of the medium 60 reaches the contact position between the application roller 14 and the impression cylinder 12, and the application liquid supplied to the application roller 14 is applied to the application roller 14 and the impression cylinder. This is the timing at which the time until moving to 12 contact positions is the same.

  That is, if the circumferential speed of the impression cylinder 12 and the circumferential speed of the application roller 14 are the same, the circumferential direction of the application roller 14 from the nip position of the anilox roller 30 with respect to the application roller 14 to the nip position of the application roller 14 with respect to the impression cylinder 12. The distance in the circumferential direction of the impression cylinder 12 from the application start position of the medium 60 to the nip position of the application roller 14 with respect to the impression cylinder 12 is the same.

  FIG. 6 schematically shows a state at the start of application of the application liquid onto the medium 60 (at the start of the nip of the application roller 14). When the application roller 14 lands on the peripheral surface of the impression cylinder 12, the medium 60 is nipped by the application roller 14 with a predetermined nip pressure, and application of the application liquid is started.

  FIG. 7 schematically illustrates the start of separation of the anilox roller 30. When a predetermined amount of the application liquid is supplied to the application roller 14, the anilox roller 30 starts to be separated from the state in contact with the application roller 14. That is, the time until the rear end (application end position) of the medium 60 reaches the contact position between the application roller 14 and the impression cylinder 12 and the end of the application liquid supplied to the application roller 14 are When the time until the cylinder 12 moves to the contact position becomes the same, the anilox rocking motor 56 is operated to separate the anilox roller 30 from the application roller 14.

  At this time, if the circumferential speed of the impression cylinder 12 and the circumferential speed of the application roller 14 are the same, the circumference of the application roller 14 from the nip position of the anilox roller 30 with respect to the application roller 14 to the nip position of the application roller 14 with respect to the impression cylinder 12. The distance in the circumferential direction of the impression cylinder 12 from the nip position of the application roller 14 to the impression cylinder 12 to the application end position of the medium 60 is the same. By controlling the contact and separation between the application roller 14 and the anilox roller 30 in this way, a necessary amount of application liquid is supplied to the application roller 14.

  Although not shown in FIGS. 3 to 7, the position of the medium on the transport path is grasped by information obtained from a position sensor provided on the transport path. Further, the rotation amount (rotation angle) and rotation speed of the impression cylinder 12 are grasped by information obtained from an encoder attached to a rotating shaft of the impression cylinder 12 or a motor that operates the impression cylinder 12. That is, the coating apparatus 10 shown in this example includes a system control system including a main control unit that performs overall control of the entire apparatus, and a control unit that individually controls each part of the apparatus using a command signal transmitted from the main control unit. ing. For example, when the main control unit acquires information from the position sensor and encoder, a command signal based on the information is sent from the main control unit to each unit of the apparatus.

  In the coating apparatus 10 shown in this example, a swinging system is adopted for separating the coating roller 14 and the anilox roller 30. Such a swinging method has a simple structure, requires a small number of parts, and is more stable in operation than a direct acting method in which the application roller 14 and the anilox roller 30 are directly moved. On the other hand, when the anilox rocking cam 48 is supported by the side plate 40 as shown in FIG. 8, the separation of the anilox roller 30 affects the nip pressure of the application roller 14 and the application unevenness occurs. Exists. In addition, the double arrow line which attached | subjected and showed the code | symbol 62 in FIG. 8 represents the application roller nip spring which abbreviate | omitted illustration in FIG.

  As shown in FIG. 9, when the anilox rocking cam 48 is rotated and the anilox rocking arm 42 is rotated clockwise with the anilox rocking fulcrum 46 as a fulcrum, the anilox nip spring of the anilox rocking arm 42 is rotated. The end on the side to which 44 is connected is pushed downward, and the anilox roller 30 is separated from the application roller 14. At this time, the anilox nip spring 44 is pulled (a broken line indicated by a double arrow indicated by reference numeral 44 '), and the application roller swing arm 38 is pulled rightward in the drawing.

  Then, an external force in the direction away from the impression cylinder 12 acts on the application roller swinging arm 38 that supports the application roller 14, and the application roller nip spring is in a state schematically illustrated with reference numeral 62 '. The nip pressure of the application roller 14 is reduced.

  When the nip pressure of the application roller 14 changes, the application state of the application liquid changes. In particular, when the nip pressure becomes smaller than a predetermined value, the film thickness of the application liquid applied to the medium 60 changes or the squeegee property decreases. This causes uneven coating.

  In order to avoid such a change in coating film thickness and occurrence of coating unevenness, as shown in FIG. 10, the coating apparatus 10 shown in this example has an anilox rocking cam 48 and an anilox rocking gear 50 as an integral structure, and anilox. Since the rotation shafts of the swing cam 48 and the anilox swing gear 50 are supported by the application roller swing arm 38, the influence on the application roller nip spring when the anilox roller 30 is separated is avoided.

  Further, since the anilox nip spring 44 is fixed to the application roller swing arm 38 and the anilox swing arm 42, the influence on the anilox nip spring 44 when the application roller 14 is separated from the impression cylinder 12 is avoided. Further, when the anilox rocker 30 is separated, the anilox rocking motor 48 (see FIG. 2) and the anilox rocking cam 48 are rotated so that the anilox rocking cam 48 and the anilox rocking gear 50 are rotated counterclockwise in the drawing. Since a transmission reaction force is generated when the gear of the anilox oscillating gear 50 rotates, it is possible to avoid a reduction in the nip pressure of the application roller 14.

[Second Embodiment]
Next, a coating apparatus according to the second embodiment of the present invention will be described. In addition, in 2nd Embodiment demonstrated below, the same code | symbol is attached | subjected to the part which is the same as that of 1st Embodiment demonstrated previously, or is similar, and the description is abbreviate | omitted.

  FIG. 11 is an overall configuration diagram of a coating unit 16 ′ applied to the coating apparatus according to the second embodiment. In the coating unit 16 ′ shown in the drawing, an anilox rocking gear 50, an anilox rocking drive gear 52, an idler gear (not shown), and an anilox rocking motor 56 are supported on the coating roller rocking arm 38.

  According to such a configuration, the influence of the driving reaction force when the gear of the anilox rocking gear 50 rotates can be avoided, and the reduction of the nip pressure of the application roller 14 when the anilox roller 30 is separated is avoided. Can do.

[Example of application to other devices]
Next, an ink jet recording apparatus (image forming apparatus) to which the coating apparatus according to the present invention is applied will be described. In the ink jet recording apparatus shown below, the coating apparatus according to the present invention is applied to a processing liquid application unit that applies a processing liquid to a recording medium before image recording.

(Overall configuration of inkjet recording apparatus)
FIG. 12 is a configuration diagram showing the overall configuration of the ink jet recording apparatus according to the present embodiment. The ink jet recording apparatus 100 shown in the figure forms an image on a recording surface of a recording medium 114 based on predetermined image data using an ink containing a color material and an aggregating treatment liquid having a function of aggregating the ink. This is a two-liquid aggregation type recording apparatus.

  The ink jet recording apparatus 100 mainly includes a paper feeding unit 120, a processing liquid application unit 130, a drawing unit 140, a drying processing unit 150, a fixing processing unit 160, and a discharge unit 170. Transfer cylinders 132, 142, 152, 162 are provided as means for delivering the recording medium 114 conveyed upstream of the treatment liquid application unit 130, the drawing unit 140, the drying processing unit 150, and the fixing processing unit 160, and the treatment liquid. As means for conveying the recording medium 114 while holding the recording medium 114 in the coating unit 130, the drawing unit 140, the drying processing unit 150, and the fixing processing unit 160, drum-shaped impression cylinders 134, 144, 154, and 164 are provided. .

  The transfer cylinders 132, 142, 152, 162 and the impression cylinders 134, 144, 154, 164 are provided with grippers 180 </ b> A, 180 </ b> B that hold the leading end portion of the recording medium 114 at predetermined positions on the outer peripheral surface. The structure for holding the tip of the recording medium 114 in the gripper 180A and the gripper 180B and the structure for transferring the recording medium 114 to and from the gripper provided in another impression cylinder or transfer cylinder are the same, and The gripper 180 </ b> A and the gripper 180 </ b> B are arranged at symmetrical positions that are moved 180 ° in the rotational direction of the pressure drum 134 on the outer peripheral surface of the pressure drum 134.

Gripper 180A, while holding the leading end portion of the recording medium 114 by 180B, rotating the transfer drum 132,142,152,162 and the impression cylinder 134,144,154,164 in a predetermined direction, pass City barrel 132 , 142, 152, 162 and the impression cylinders 134, 144, 154, 164 are rotated and conveyed along the outer peripheral surface.

  In FIG. 12, only the grippers 180 </ b> A and 180 </ b> B included in the impression cylinder 134 are denoted by reference numerals, and the other impression cylinders and the transfer cylinder grippers are omitted.

  When the recording medium (sheet) 114 accommodated in the paper supply unit 120 is fed to the treatment liquid application unit 130, the aggregation process is performed on the recording surface of the recording medium 114 held on the outer peripheral surface of the impression cylinder 134. A liquid (hereinafter simply referred to as “treatment liquid”) is applied. The “recording surface of the recording medium 114” is an outer surface in a state where the impression cylinders 134, 144, 154, 164 are held, and is a surface opposite to the surface held by the impression cylinders 134, 144, 154, 164. It is.

  Thereafter, the recording medium 114 to which the aggregation treatment liquid has been applied is sent to the drawing unit 140, and color ink is applied to the area of the recording surface to which the aggregation treatment liquid has been applied, thereby forming a desired image.

  Further, the recording medium 114 on which the image of the color ink is formed is sent to the drying processing unit 150, where the drying processing unit 150 performs the drying processing, and after the drying processing, the recording medium 114 is sent to the fixing processing unit 160 to perform the fixing processing. Applied. By performing the drying process and the fixing process, the image formed on the recording medium 114 is hardened. In this manner, a desired image is formed on the recording surface of the recording medium 114, and after the image is fixed on the recording surface of the recording medium 114, the image is conveyed from the discharge unit 170 to the outside of the apparatus.

(Paper Feeder)
The paper feeding unit 120 is provided with a paper feeding tray 122 and a feeding mechanism (not shown), and the recording medium 114 is configured to be fed one by one from the paper feeding tray 122. The recording medium 114 sent out from the paper feed tray 122 is positioned by a guide member (not shown) so that the leading end is positioned at a gripper (not shown) of the transfer drum (paper feed drum) 132 and temporarily stops.

(Processing liquid application part)
The treatment liquid application unit 130 holds the recording medium 114 delivered from the paper feed cylinder 132 on the outer peripheral surface and conveys the recording medium 114 in a predetermined conveyance direction, and a treatment liquid cylinder. And a processing liquid coating device 136 that applies a processing liquid to the recording surface of the recording medium 114 held on the outer peripheral surface of 134. When the processing liquid cylinder 134 is rotated counterclockwise in FIG. 12, the recording medium 114 is conveyed in a counterclockwise direction along the outer peripheral surface of the processing liquid cylinder 134.

  The processing liquid coating device 136 shown in FIG. 12 is provided at a position facing the outer peripheral surface (recording medium holding surface) of the processing liquid cylinder 134. 12 corresponds to the pressure drum 12 of FIGS. 1 and 2, and the transfer drum 132 shown in FIG. 12 corresponds to the transfer drum 28 of FIG. 12 corresponds to the application unit 16 of FIGS. 1 and 2 and the application unit 16 'of FIG.

  The processing liquid applied to the recording medium 114 by the processing liquid coating apparatus 136 contains a color material flocculant that aggregates the color material (pigment) in the ink applied by the drawing unit 140, and the processing liquid is applied on the recording medium 114. And the ink come into contact with each other, the separation of the color material and the solvent in the ink is promoted.

(Drawing part)
The drawing unit 140 includes an impression cylinder (drawing cylinder) 144 that holds and conveys the recording medium 114, a sheet suppression roller 146 for bringing the recording medium 114 into close contact with the drawing cylinder 144, and an inkjet that applies ink to the recording medium 114. Heads 148M, 148K, 148C, and 148Y are provided. The basic structure of the drawing cylinder 144 is the same as that of the processing liquid cylinder 134 described above, and a description thereof is omitted here.

  The paper holding roller 146 is a guide member for bringing the recording medium 114 into close contact with the outer peripheral surface of the drawing cylinder 144, faces the outer peripheral surface of the drawing cylinder 144, and delivers the recording medium 114 between the transfer cylinder 142 and the drawing cylinder 144. It is disposed downstream of the position in the transport direction of the recording medium 114 and upstream of the inkjet heads 148M, 148K, 148C, and 148Y in the transport direction of the recording medium 114.

  The recording medium 114 transferred from the transfer cylinder 142 to the drawing cylinder 144 is pressed by the sheet pressing roller 146 when being rotated and conveyed with the leading end held by a gripper (reference numeral omitted), and the outer periphery of the drawing cylinder 144 Adhere to the surface. After the recording medium 114 is brought into close contact with the outer peripheral surface of the drawing cylinder 144 in this way, the recording medium 114 is sent to the print area immediately below the ink jet heads 148M, 148K, 148C, 148Y without being lifted from the outer peripheral surface of the drawing cylinder 144. It is done.

  The inkjet heads 148M, 148K, 148C, and 148Y correspond to inks of four colors, magenta (M), black (K), cyan (C), and yellow (Y), respectively, and the rotation direction of the drawing cylinder 144 (see FIG. 12 in the counterclockwise direction in FIG. 12, and the ink discharge surfaces of the inkjet heads 148M, 148K, 148C, and 148Y are disposed so as to face the recording surface of the recording medium 114 held by the drawing cylinder 144. Is done. The “ink ejection surface (nozzle surface)” is a surface of the inkjet heads 148M, 148K, 148C, and 148Y that faces the recording surface of the recording medium 114, and is a surface on which nozzles for ejecting ink to be described later are formed. It is.

  In addition, in the inkjet heads 148M, 148K, 148C, and 148Y shown in FIG. 12, the recording surface of the recording medium 114 held on the outer peripheral surface of the drawing cylinder 144 and the nozzle surfaces of the inkjet heads 148M, 148K, 148C, and 148Y are substantially parallel. In such a manner, it is arranged to be inclined with respect to the horizontal plane.

  The inkjet heads 148M, 148K, 148C, and 148Y are full-line heads having a length corresponding to the maximum width of the image forming area in the recording medium 114 (the length in the direction orthogonal to the conveyance direction of the recording medium 114). The recording medium 114 is fixedly installed so as to extend in a direction orthogonal to the conveyance direction of the recording medium 114.

  On the nozzle surfaces (liquid ejection surfaces) of the inkjet heads 148M, 148K, 148C, and 148Y, nozzles for ejecting ink are formed in a matrix arrangement over the entire width of the image forming area of the recording medium 114.

  When the recording medium 114 is conveyed to a printing area immediately below the inkjet heads 148M, 148K, 148C, and 148Y, the image data is applied to the area where the aggregation processing liquid of the recording medium 114 is applied from the inkjet heads 148M, 148K, 148C, and 148Y. Based on this, ink of each color is ejected (droplet ejection).

  When droplets of the corresponding color ink are ejected from the inkjet heads 148M, 148K, 148C, and 148Y toward the recording surface of the recording medium 114 held on the outer peripheral surface of the drawing cylinder 144, processing is performed on the recording medium 114. The liquid and the ink come into contact with each other, and an aggregation reaction of the color material (pigment-based color material) dispersed in the ink or the color material (dye-based color material) to be insolubilized appears, and a color material aggregate is formed. As a result, movement of the color material (dot misalignment, dot color unevenness) in the image formed on the recording medium 114 is prevented.

  In addition, since the drawing cylinder 144 of the drawing unit 140 is structurally separated from the processing liquid cylinder 134 of the processing liquid application unit 130, the processing liquid does not adhere to the inkjet heads 148M, 148K, 148C, and 148Y. In addition, the cause of abnormal ink ejection can be reduced.

  In this example, the configuration of CMYK standard colors (four colors) is illustrated, but the combination of ink colors and the number of colors is not limited to this embodiment, and light ink, dark ink, and special colors are used as necessary. Ink may be added. For example, it is possible to add an inkjet head that discharges light-colored ink such as light cyan and light magenta, and the arrangement order of the color heads is not particularly limited.

(Dry processing part)
The drying processing unit 150 holds an impression cylinder (drying cylinder) 154 that holds and conveys the recording medium 114 after image formation, and a drying processing device 156 that performs a drying process for evaporating moisture (liquid component) on the recording medium 114. It has. The basic structure of the drying cylinder 154 is the same as that of the processing liquid cylinder 134 and the drawing cylinder 144 described above, and a description thereof is omitted here.

  The drying processing device 156 is a processing unit that is disposed at a position facing the outer peripheral surface of the drying drum 154 and evaporates moisture present in the recording medium 114. When ink is applied to the recording medium 114 by the drawing unit 140, the liquid component (solvent component) of the ink and the liquid component (solvent component) of the processing liquid separated by the aggregation reaction between the processing liquid and the ink are placed on the recording medium 114. Since it remains, it is necessary to remove such a liquid component.

The drying processing device 156 performs a drying process for evaporating the liquid component existing on the recording medium 114 by heating with a heater, blowing with a fan, or a combination thereof, and removing the liquid component on the recording medium 114. Part. The amount of heating and the amount of air blown to the recording medium 114 are appropriately set according to parameters such as the amount of moisture remaining on the recording medium 114, the type of the recording medium 114, and the conveyance speed (interference processing time) of the recording medium 114. Is done.

  When the drying processing by the drying processing device 156 is performed, the drying cylinder 154 of the drying processing unit 150 is structurally separated from the drawing cylinder 144 of the drawing unit 140, so the inkjet heads 148M, 148K, 148C, and 148Y. In this case, it is possible to reduce the cause of abnormal ink ejection due to drying of the head meniscus by heat or air blowing.

  Means (for example, a built-in heater) for adjusting the surface temperature of the drying drum 154 may be provided, and the surface temperature may be adjusted to 50 ° C. or higher. By performing heat treatment from the back surface of the recording medium 114, drying is promoted, and image destruction during the fixing process of the next stage is prevented. In such an embodiment, it is more effective to provide means for bringing the recording medium 114 into close contact with the outer peripheral surface of the drying drum 154. Examples of means for closely attaching the recording medium 114 include vacuum suction and electrostatic suction.

  The upper limit of the surface temperature of the drying cylinder 154 is not particularly limited, but from the viewpoint of safety of maintenance work such as cleaning ink adhering to the surface of the drying cylinder 154 (preventing burns due to high temperatures). It is preferably set to 75 ° C. or lower (more preferably 60 ° C. or lower).

  The drying drum 154 configured in this manner is held on the outer peripheral surface of the recording medium 114 so that the recording surface of the recording medium 114 faces outward (that is, in a state where the recording surface of the recording medium 114 is convex). By performing the drying process while rotating and transporting, drying unevenness due to wrinkling or floating of the recording medium 114 is surely prevented.

(Fixing processing part)
The fixing processing unit 160 includes a pressure drum (fixing drum) 164 that holds and conveys the recording medium 114, a heater 166 that performs heat treatment on the recording medium 114 on which an image is formed and liquid is removed, and the recording And a fixing roller 168 that presses the medium 114 from the recording surface side. The basic structure of the fixing cylinder 164 is the same as that of the processing liquid cylinder 134, the drawing cylinder 144, and the drying cylinder 154, and a description thereof is omitted here. The heater 166 and the fixing roller 168 are disposed at positions facing the outer peripheral surface of the fixing cylinder 164, and are sequentially disposed from the upstream side in the rotation direction of the fixing cylinder 164 (counterclockwise direction in FIG. 12).

  In the fixing processing unit 160, the recording surface of the recording medium 114 is subjected to preheating processing by the heater 166 and fixing processing by the fixing roller 168. The heating temperature of the heater 166 is appropriately set according to the type of recording medium, the type of ink (the type of polymer fine particles contained in the ink), and the like. For example, a mode in which the glass transition temperature and the minimum film forming temperature of the polymer fine particles contained in the ink are considered.

  The fixing roller 168 is a roller member for heating and pressurizing the dried ink to weld the self-dispersing polymer fine particles in the ink to form a film of the ink, and is configured to heat and press the recording medium 114. The Specifically, the fixing roller 168 is disposed so as to be in pressure contact with the fixing cylinder 164 and constitutes a nip roller with the fixing cylinder 164. As a result, the recording medium 114 is sandwiched between the fixing roller 168 and the fixing cylinder 164 and nipped at a predetermined nip pressure, and the fixing process is performed.

  As an example of the configuration of the fixing roller 168, there is an aspect in which the fixing roller 168 is configured by a heating roller in which a halogen lamp is incorporated in a metal pipe such as aluminum having good thermal conductivity. By heating the recording medium 114 with such a heating roller, when thermal energy equal to or higher than the glass transition temperature of the polymer fine particles contained in the ink is applied, the polymer fine particles are melted to form a transparent film on the surface of the image. Is done.

  When pressure is applied to the recording surface of the recording medium 114 in this state, the polymer fine particles melted into the unevenness of the recording medium 114 are pressed and fixed, and the unevenness of the image surface is leveled, so that preferable glossiness can be obtained. A configuration in which a plurality of fixing rollers 168 are provided in accordance with the thickness of the image layer and the glass transition temperature characteristics of the polymer particles is also preferable.

  The surface hardness of the fixing roller 168 is preferably 71 ° or less. By making the surface of the fixing roller 168 softer, a follow-up effect can be expected with respect to the unevenness of the recording medium 114 caused by cockling, and fixing unevenness due to the unevenness of the recording medium 114 is more effectively prevented. .

  In the inkjet recording apparatus 100 shown in FIG. 12, an inline sensor 182 is provided at the subsequent stage (downstream in the recording medium conveyance direction) of the processing area of the fixing processing unit 160. The inline sensor 182 is a sensor for reading an image formed on the recording medium 114 (or a check pattern formed in a blank area of the recording medium 114), and a CCD line sensor is preferably used.

  In the ink jet recording apparatus 100 shown in this example, the presence or absence of ejection abnormality of the ink jet heads 148M, 148K, 148C, and 148Y is determined based on the reading result of the inline sensor 182. Further, the inline sensor 182 may include a measuring unit for measuring a moisture amount, a surface temperature, a glossiness, and the like. In such an embodiment, parameters such as the processing temperature of the drying processing unit 150, the heating temperature of the fixing processing unit 160, and the pressure pressure are appropriately adjusted based on the reading results of the moisture content, surface temperature, and glossiness, and the temperature inside the apparatus. The control parameter is adjusted as appropriate in accordance with the change and the temperature change of each part.

(Discharge part)
As shown in FIG. 12, a discharge unit 170 is provided following the fixing processing unit 160. The discharge unit 170 includes an endless conveyance chain 174 wound around the stretching rollers 172A and 172B, and a discharge tray 176 that stores the recording medium 114 after image formation.

  The recording medium 114 after the fixing process sent out from the fixing processing unit 160 is transported by the transport chain 174 and discharged to the discharge tray 176.

  As the inkjet heads 148M, 148K, 148C, and 148Y provided in the drawing unit 140, a full-line head having a structure in which a plurality of nozzles are arranged on the nozzle surface over a length corresponding to the entire width of the recording medium 114 is applied. The For example, a plurality of ink chamber units (droplet ejection elements as recording element units) including nozzles that are ink ejection ports, pressure chambers that communicate with the nozzles, supply ports that communicate the common flow path and the pressure chambers, and the like ) Is applied in a matrix arrangement.

  Note that, as a form of forming one or more nozzle rows over a length corresponding to the entire width of the recording medium 114, short head modules in which a plurality of nozzles are two-dimensionally arranged are arranged in a staggered manner and connected. By increasing the length, a line head having a nozzle row having a length corresponding to the entire width of the recording medium 114 as a whole may be configured. Further, a line head may be configured by arranging short head modules that do not reach the full width of the recording medium 114 in a line.

Inkjet head 148m, 148K, 148C, as an ejection method of 148Y, the vibration plate constituting the upper surface of the pressure chamber, distribution piezoelectric element having a piezoelectric body is sandwiched structure between the individual separate electrodes and the common electrode A piezoelectric method is applied in which a diaphragm is deformed by applying a predetermined drive voltage between the individual electrode and the common electrode, and ink having a volume corresponding to the volume change of the pressure chamber is ejected. Of course, it is also possible to apply a thermal method in which a heater is provided in the pressure chamber and ink is ejected using the pressure of film boiling caused by heating of the heater.

[Explanation of control system]
FIG. 13 is a block diagram illustrating a schematic configuration of a control system of the inkjet recording apparatus 100. The inkjet recording apparatus 100 includes a communication interface 240, a system control unit 242, a conveyance control unit 244, an image processing unit 246, and a head drive unit 248, and also includes a storage unit (memory) 250 and a temporary storage unit 252.

  The communication interface 240 is an interface unit that receives image data sent from the host computer 254. The communication interface 240 may be a serial interface such as USB (Universal Serial Bus) or a parallel interface such as Centronics. The communication interface 240 may include a buffer memory (not shown) for speeding up communication.

  The system control unit 242 includes a central processing unit (CPU) and its peripheral circuits, and functions as a control device that controls the entire inkjet recording apparatus 100 according to a predetermined program, and also functions as an arithmetic device that performs various calculations. Further, it functions as a memory controller for the storage unit 250 and the temporary storage unit 252. That is, the system control unit 242 controls each unit such as the communication interface 240 and the conveyance control unit 244, performs communication control with the host computer 254, read / write control of the storage unit 250 and the temporary storage unit 252, and the like. A control signal is generated to control each part.

  Image data sent from the host computer 254 is taken into the ink jet recording apparatus 100 via the communication interface 240, and predetermined image processing is performed by the image processing unit 246.

  The image processing unit 246 has a signal (image) processing function for performing various processing and correction processing for generating a print control signal from the image data, and supplies the generated print data to the head driving unit 248. It is a control unit. Necessary signal processing is performed in the image processing unit 246, and based on the image data, the ejection droplet amount (droplet ejection amount) and ejection of the head 148 (148M, 148K, 148C, 148Y) via the head driving unit 248 Timing control is performed. Thereby, a desired dot size and dot arrangement are realized. The head driving unit 248 shown in FIG. 13 may include a feedback control system for keeping the driving conditions of the head 148 constant.

The conveyance control unit 244 controls the conveyance timing and conveyance speed of the recording medium 114 (see FIG. 12) based on the print control signal generated by the image processing unit 246. Conveyance drive unit 156 in FIG. 13, a motor and rotating the impression cylinder 134,144,154,164 of Figure 12, a motor for rotating the passed City cylinders 132,142,152,162, recording in the paper feed unit 120 medium 114 Including a motor for driving the tension roller 172A (172B) of the discharge unit 170, and the conveyance control unit 244 functions as a driver for the motor.

  The storage unit 250 stores a program executed by the CPU of the system control unit 242, various data necessary for controlling each unit of the apparatus, control parameters, and the like, and data is read and written through the system control unit 242. The storage unit 250 is not limited to a memory made of a semiconductor element, and may use a magnetic medium such as a hard disk. Alternatively, a removable storage medium that includes an external interface may be used.

  The temporary storage unit (temporary storage memory) 252 functions as a temporary storage unit that temporarily stores image data input via the communication interface 240, a development area for various programs stored in the storage unit 250, and a CPU. It has a function as a calculation work area (for example, a work area of the image processing unit 246). As the temporary storage unit 252, a volatile memory (RAM) capable of sequential reading and writing is used.

  Further, the inkjet recording apparatus 100 includes a processing liquid application control unit 260, a drying processing control unit 262, and a fixing processing control unit 264, and in accordance with instructions from the system control unit 242, each of the processing liquid application units 130 is provided. The operation of each unit of the fixing processing unit 160 including the drying processing unit 150, the heater 166, and the fixing roller 168 (see FIG. 12) is controlled.

Based on the print data obtained from the image processing unit 246, the processing liquid application control unit 260 controls the processing liquid application timing and the application amount of the processing liquid. Although the details will be described later, the processing liquid coating apparatus (shown with reference numeral 136 in FIG. 2 ) provided in the processing liquid coating unit 130 is in contrast to the impression cylinder (shown with reference numeral 12 in FIG. 2). An application roller moving mechanism (see FIG. 2) for moving the application roller is provided so that the application roller (shown by reference numeral 14 in FIG. 1) can be contacted (contacted) and separated. On the other hand, the anilox is moved so that the anilox roller (shown with reference numeral 30 in FIG. 2) for measuring the amount of the processing liquid supplied to the coating roller can be brought into contact (contact) and separated. A roller moving mechanism (see FIG. 2) is provided.

  The processing liquid application control unit 260 shown in FIG. 13 controls the contact timing and separation timing between the anilox roller and the application roller, and also controls the contact timing and separation timing between the application roller and the recording medium. Such a treatment liquid application control unit 260 can be applied to the control system of the coating apparatus described with reference to FIGS.

  The drying process control unit 262 controls the timing of the drying process and controls the processing temperature, the air flow rate, and the like. The fixing process control unit 264 controls the temperature of the heater 166 and also controls the pressing of the fixing roller 168. .

  The detection unit 266 is a processing block including the inline sensor 182 illustrated in FIG. 12 and a signal processing unit that performs predetermined signal processing such as nozzle removal, amplification, and waveform shaping on the read signal output from the inline sensor 182. The system control unit 242 determines whether there is an ejection abnormality of the head 148 based on the detection signal obtained by the detection unit 266.

  The encoder 268 is attached to a motor serving as a drive source for rotating the impression cylinders 134, 144, 154, and 164, and a pulse signal corresponding to the rotation of the motor is output. By counting the pulse signals output from the encoder 268, the amount of rotation of the impression cylinders 134, 144, 154, 164 can be grasped. Further, the rotation unevenness of the impression cylinders 134, 144, 154, 164 can be grasped based on the frequency fluctuation of the pulse signal output from the encoder 268.

  That is, the pulse train output from the encoder 268 is subjected to predetermined signal processing such as waveform shaping and noise removal, and is sent to the system control unit 242. Based on the pulse train acquired from the encoder 268, the system control unit 242 sends command signals for controlling the application roller contact timing, separation timing, anilox roller contact timing, and separation timing to the processing liquid application control unit 260. Send it out.

  The paper sensor 270 is a sensor provided in the conveyance path of the recording medium 114, and can determine the position of the recording medium 114 on the conveyance path based on the detection result of the paper sensor 270. For example, when the paper sensor 270 provided in the vicinity of the gripper 180 of the impression cylinder 134 (144, 154, 164) detects the recording medium 114, the gripper 180 is operated to clamp the leading end of the recording medium 114, and the impression cylinder 134 is operated. The adsorption control and temperature control are switched to the recording medium holding state.

  In FIG. 13, a plurality of paper sensors provided on the conveyance path of the recording medium are represented by a reference numeral 270. The configuration including the encoder 268 and the paper sensor 270 is applied to the coating apparatus described with reference to FIGS.

  The application range of the coating apparatus according to the present invention is not limited to the ink jet recording apparatus, and can be widely applied to apparatuses having a coating unit that applies a predetermined coating liquid to a processing target medium. In addition, in the interpretation of the term "image forming apparatus", it is not limited to the use of so-called graphic printing such as photographic printing or poster printing, such as a resist printing apparatus, a wiring drawing apparatus for an electronic circuit board, a fine structure forming apparatus, etc. An industrial use apparatus capable of forming a pattern that can be grasped as an image is also included.

  The medium applied to the coating apparatus according to the present invention includes various media on which a predetermined coating liquid can be applied by a roller coating method, such as paper, resin sheets, sheet-shaped media such as metal sheets, and the like. Is included.

  The coating apparatus according to the present invention and the image forming apparatus to which the coating apparatus is applied have been described above. However, the scope of the present invention is not limited to the above-described embodiment, and appropriate modifications, improvements, and the like are made. be able to.

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

  (Invention 1): A cylinder having a cylindrical shape and conveying a medium held on the circumferential surface along the circumferential direction; an application roller for applying a liquid to the medium held on the circumferential surface of the impression cylinder; An application roller urging portion that urges the application roller to the peripheral surface of the impression cylinder, a separation mechanism that separates the application roller from the peripheral surface of the impression cylinder, and an application roller that swingably supports the application roller. A support unit; a supply roller that supplies a predetermined amount of liquid to the application roller; and a moving unit that moves the supply roller so as to switch contact and separation between the supply roller and the application roller. The moving means is integrated with the supply roller support portion for swingably supporting the supply roller, the supply roller swing cam for moving the supply roller support portion according to a predetermined cam curve, and the supply roller swing cam. Configured to A supply roller oscillating gear whose rotation shaft is supported by the application roller support portion, and the rotation axis of the supply roller oscillation cam and the rotation shaft of the supply roller oscillation gear are the application roller support portion. A coating apparatus characterized by having a structure supported on the surface.

  According to the present invention, the moving means for moving the supply roller includes a supply roller support portion that supports the supply roller in a swingable manner, and a supply roller swing cam that moves the supply roller support portion according to a predetermined cam curve, Since the rotation shaft of the supply roller swing cam and the rotation shaft of the supply roller swing gear configured integrally with the supply roller swing cam are configured to be supported by the application roller support portion, the supply roller is removed from the application roller. The contact pressure of the application roller with respect to the medium to be applied does not decrease due to the movement of the supply roller during separation, and the contact pressure of the supply roller with respect to the application roller decreases when the application roller is separated from the impression cylinder. There is nothing to do.

(Invention 2): In the coating apparatus according to Invention 1, the moving means may prevent the contact pressure of the application roller against the medium from decreasing when the supply roller is separated from the application roller. The rotating shaft of the supply roller swing cam and the rotation shaft of the supply roller swing gear are configured to rotate in a predetermined direction.

  According to this aspect, the driving reaction force of the supply roller swinging gear is suppressed, and a decrease in the contact pressure of the application roller on the medium can be avoided.

  (Invention 3): In the coating apparatus according to Invention 1 or 2, an elastic member having a structure in which one end is fixed to the application roller support portion and the other end is fixed to the supply roller support portion, And a supply roller urging portion that urges the supply roller to the application roller.

  According to this aspect, the supply roller is urged against the application roller by the elastic force (restoring force) of the elastic member.

  (Invention 4): In the coating apparatus according to any one of Inventions 1 to 3, the supply roller is swingably supported with a swing fulcrum shaft supported by the coating roller support portion as a fulcrum. And

  According to this aspect, by applying the swing method to the moving means for moving the supply roller, the structure of the moving means can be further simplified, and the accuracy of the positional relationship between the application roller and the supply roller is improved. To do.

  (Invention 5): In the coating apparatus according to any one of Inventions 1 to 4, the moving means includes a drive source connected to a rotation shaft of the supply roller rocking cam and a rotation shaft of the supply roller rocking gear. And a structure supported by the coating roller support portion.

  According to this aspect, since the driving source for swinging the supply roller is supported by the application roller support member, the swing of the supply roller does not affect the contact pressure of the application roller with respect to the medium, and Application unevenness when the supply roller is separated is avoided.

  (Invention 6): In the coating apparatus according to any one of Inventions 1 to 5, the separation mechanism is located at a position corresponding to an arrangement position of a holding member that holds an end portion of a medium provided on a peripheral surface of the impression cylinder. And a protrusion protruding from the circumferential surface of the impression cylinder, the coating roller being provided and having a structure in which an application roller in contact with the circumferential surface of the impression cylinder rides up.

  According to this aspect, the contact between the application member and the holding member that holds the medium is avoided.

  (Invention 7): In the coating apparatus according to any one of Inventions 1 to 6, application roller rotation means for rotating the application roller at a predetermined rotation speed, and supply roller rotation for rotating the supply roller at a predetermined rotation speed And the time until the application start position of the medium moves to the contact position between the application roller and the impression cylinder, the liquid at the contact position between the supply roller and the application roller is transferred between the application roller and the pressure roller. Control means for controlling the operation timing of the moving means so as to bring the supply roller into contact with the application roller at the same timing as the time until the position of contact with the drum is reached.

  According to this aspect, since the application liquid is supplied to the application roller in accordance with the timing at which the medium application start position moves to the contact position between the application roller and the impression cylinder, excess application liquid adheres to the application roller. do not do.

  (Invention 8): In the coating apparatus according to Invention 7, the control unit is configured so that the time until the application end position of the medium moves to a contact position between the application roller and the impression cylinder, Operation of the moving means to move the supply roller away from the application roller at the same timing as the time required for the liquid at the position of contact with the application roller to move to the contact position between the application roller and the impression cylinder It is characterized by controlling the timing.

  According to this aspect, since the supply of the application liquid to the application roller is stopped in accordance with the timing at which the application end position of the medium moves to the contact position between the application roller and the impression cylinder, excessive application to the application roller Liquid does not adhere.

  (Invention 9): A cylinder that has a cylindrical shape and conveys a medium held on the circumferential surface along the circumferential direction, and a coating apparatus that applies a liquid to the medium held on the circumferential surface of the impression cylinder; Image forming means for forming an image on a medium coated with a liquid by the coating device, the coating device applying a liquid to a medium held on a peripheral surface of the impression cylinder, An application roller urging portion that urges the application roller to the peripheral surface of the impression cylinder, a separation mechanism that separates the application roller from the peripheral surface of the impression cylinder, and an application roller support that supports the application roller in a swingable manner. A supply roller for supplying a predetermined amount of liquid to the application roller, and a moving means for moving the supply roller so as to switch contact and separation between the supply roller and the application roller, The moving means includes the supply roller Comprising a transmission mechanism to be sintered, wherein the transmission mechanism is an image forming apparatus characterized by having a structure supported by the application roller supporting portion.

  An ink jet recording apparatus as one aspect of an image forming apparatus according to the present invention includes a nozzle (discharge port) for discharging ink droplets for forming dots and a pressure generating element (piezoelectric actuator or heating) for generating discharge pressure. A liquid discharge head (recording head) in which a large number of droplet discharge elements including a foaming heating element) are arranged at high density, and the liquid is based on ink discharge data (dot image data) generated from an input image. An ejection control unit that controls ejection of droplets from the ejection head, and forms an image on the recording medium by the droplets ejected from the nozzles.

  (Invention 10): In the image forming apparatus described in Invention 9, the coating apparatus applies a treatment liquid having a function of aggregating or insolubilizing ink used for image formation by the image forming unit to the medium. And

  According to this aspect, the application of the treatment liquid is stable, and preferable image formation is realized.

  DESCRIPTION OF SYMBOLS 10 ... Application | coating apparatus, 12,134 ... Impression cylinder, 14 ... Application | coating roller, 16, 16 '... Application | coating part, 24 ... Cam part, 30 ... Anilox roller, 38 ... Application roller rocking | fluctuating arm, 42 ... Anilox rocking | fluctuation arm, 44 ... Anilox nip spring, 46 ... Anilox rocking fulcrum, 50 ... Anilox rocking gear, 56 ... Anilox rocking motor, 100 ... Inkjet recording device, 130 ... Treatment liquid application unit, 136 ... Treatment liquid application device

Claims (9)

An impression cylinder having a cylindrical shape and conveying a medium held on the circumferential surface along the circumferential direction;
An application roller for applying a liquid to the medium held on the peripheral surface of the impression cylinder;
An application roller urging portion for urging the application roller to the peripheral surface of the impression cylinder;
A separation mechanism for separating the application roller from the circumferential surface of the impression cylinder;
An applicator roller support that supports the applicator roller in a swingable manner;
A supply roller for supplying a predetermined amount of liquid measured to the application roller;
Moving means for moving the supply roller so as to switch contact and separation between the supply roller and the application roller;
A supply roller urging portion for urging the supply roller to the application roller;
With
The moving means includes a supply roller support that supports the supply roller in a swingable manner;
A supply roller swing cam for moving the supply roller support portion according to a predetermined cam curve;
A supply roller rocking gear that is integrally formed with the supply roller rocking cam and whose rotation shaft is supported by the coating roller support portion, and the rotation shaft of the supply roller rocking cam and the supply roller rocking the rotation axis of the gear, and have a structure that is supported by the application roller supporting portion,
The application roller biasing portion includes an elastic member having a structure in which one end is fixed to the application roller support portion and the other end is fixed to the supply roller support portion . The coating apparatus according to claim 1,
The moving means moves the rotation shaft of the supply roller oscillating cam and the supply roller oscillating so that the contact pressure of the application roller on the medium does not decrease when the supply roller is separated from the application roller. A coating apparatus having a structure for rotating a rotation shaft of a gear in a predetermined direction. The coating apparatus according to claim 1 or 2 ,
The coating apparatus is characterized in that the supply roller is swingably supported with a swing fulcrum shaft supported by the coating roller support portion as a fulcrum. In the coating device in any one of Claims 1 thru | or 3 ,
The moving means has a structure in which a driving source connected to a rotation shaft of the supply roller swing cam and a rotation shaft of the supply roller swing gear is supported by the coating roller support portion. apparatus. In the coating device in any one of Claims 1 thru | or 4 ,
The separation mechanism is provided at a position corresponding to an arrangement position of a clamping member that clamps an end portion of a medium provided on the circumferential surface of the impression cylinder, and a coating roller that is in contact with the circumferential surface of the impression cylinder rides up. A coating apparatus comprising: a protrusion protruding from a peripheral surface of the impression cylinder. In the coating device according to any one of claims 1 to 5 ,
Application roller rotating means for rotating the application roller at a predetermined rotation speed;
Supply roller rotating means for rotating the supply roller at a predetermined rotation speed;
The time until the application start position of the medium moves to the contact position between the application roller and the impression cylinder is such that the liquid in the contact position between the supply roller and the application roller is between the application roller and the impression cylinder. An applicator comprising control means for controlling the operation timing of the moving means so that the supply roller comes into contact with the applicator roller at a timing that is the same as the time required to move to the contact position. The coating apparatus according to claim 6 , wherein
The control means is configured such that the time until the application end position of the medium moves to the contact position between the application roller and the impression cylinder is such that the liquid at the contact position between the supply roller and the application roller is An application apparatus that controls the operation timing of the moving means so that the supply roller is separated from the application roller at a timing that is the same as the time until it moves to the contact position with the impression cylinder. An impression cylinder having a cylindrical shape and conveying a medium held on the circumferential surface along the circumferential direction;
An application device for applying a liquid to the medium held on the peripheral surface of the impression cylinder;
Image forming means for forming an image on a medium coated with liquid by the coating device;
Comprising
The application device includes an application roller for applying a liquid to a medium held on the peripheral surface of the impression cylinder;
An application roller urging portion for urging the application roller to the peripheral surface of the impression cylinder;
A separation mechanism for separating the application roller from the circumferential surface of the impression cylinder;
An applicator roller support that supports the applicator roller in a swingable manner;
A supply roller for supplying a predetermined amount of liquid measured to the application roller;
Moving means for moving the supply roller so as to switch contact and separation between the supply roller and the application roller;
A supply roller urging portion for urging the supply roller to the application roller;
With
The moving means includes a supply roller support that supports the supply roller in a swingable manner;
A supply roller swing cam for moving the supply roller support portion according to a predetermined cam curve;
A supply roller rocking gear that is integrally formed with the supply roller rocking cam and whose rotation shaft is supported by the coating roller support portion, and the rotation shaft of the supply roller rocking cam and the supply roller rocking the rotation axis of the gear have a structure that is supported by the application roller supporting portion,
The image forming apparatus according to claim 1, wherein the supply roller urging portion includes an elastic member having a structure in which one end is fixed to the application roller support portion and the other end is fixed to the supply roller support portion . The image forming apparatus according to claim 8 .
The image forming apparatus is characterized in that the coating apparatus applies a treatment liquid having a function of aggregating or insolubilizing ink used for image formation by the image forming unit to the medium.

Images