JP2014188961A - Printer and printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain equal image quality between medium conveyance modes having different speeds in a printer.SOLUTION: A printer 1 performs image formation by discharging ultraviolet curable type ink 10 to a medium 5 being conveyed in a conveyance path 8 and by performing ultraviolet irradiation by an ultraviolet light source 61 to the ink 10 which landed on the medium 5. The printer includes: a speed control unit 110 for switching a medium conveyance speed between a first mode in which the conveyance speed of the medium 5 is set at a predetermined speed, and a second mode in which the conveyance speed of the medium 5 is set higher than the predetermined speed; an irradiation position changing member 80 for changing an ultraviolet irradiation position 13 on the medium 5 by the ultraviolet light source 61; and an irradiation position control unit 111 which makes the ultraviolet irradiation position 13 transit to the conveyance path downstream side further than a predetermined position 12 on the medium 5 during the first mode, and makes the ultraviolet irradiation position 13 transit to the conveyance path upstream side further than the predetermined position 12 on the medium 5 during the second mode, by controlling the irradiation position changing member 80.

Description

  The present invention relates to a printing apparatus and a printing method.

  2. Description of the Related Art A so-called ink jet printer is known that forms an image by discharging ultraviolet curable ink from a head toward a medium and irradiating the ink that has landed on the medium with ultraviolet rays to cure the ink. For such printers, methods have been proposed for obtaining good image quality by performing function control flexibly corresponding to various conditions.

  As such a technique, for example, in an image forming method in which ink that is cured by actinic rays is ejected onto the surface of a recording material with a recording head having at least one nozzle that can selectively control ejection of ink droplets, A technique (see Patent Document 1) that arbitrarily changes the irradiation condition of light is known.

JP 2003-191594 A

  By the way, the above-described printer has a mode for conveying a medium at a high speed (for example, 15 m / min) and a mode for conveying at a low speed (for example, 7.5 m / min) according to the receiving speed of image forming data from the outside. There are cases where two operation modes are provided. In such a printer, since the distance between the head that ejects ink and the ultraviolet light source is constant, the time from when the ink lands on the medium until the start of ultraviolet irradiation depends on the conveyance speed of the medium. Will be determined. That is, the time required to start the irradiation of ultraviolet rays to the ink differs between the above-described two operation modes.

  On the other hand, the ink described above has a property of spreading on the medium until it is cured by ultraviolet rays. If the operation mode is changed and executed, the state of wetting and spreading on the medium is changed between the operation modes. A different situation occurs, that is, the picture quality of the image formed on the medium differs between the operation modes.

  SUMMARY An advantage of some aspects of the invention is that it is possible to obtain equivalent image quality between medium conveyance modes having different speeds in a printing apparatus.

The main invention for achieving the above object is:
A printing apparatus that forms an image by ejecting ultraviolet curable ink onto a medium being conveyed through a conveyance path and irradiating the ink landed on the medium with ultraviolet light from an ultraviolet light source.
A speed control unit that switches the medium conveyance speed between a first mode in which the medium conveyance speed is a predetermined speed and a second mode in which the medium conveyance speed is higher than the predetermined speed;
An irradiation position changing member for changing an ultraviolet irradiation position on the medium by the ultraviolet light source;
By controlling the irradiation position changing member, the ultraviolet irradiation position is shifted downstream from the predetermined position on the medium in the first mode in the first mode, and from the predetermined position on the medium in the second mode. An irradiation position control unit for shifting the ultraviolet irradiation position to the upstream side of the conveyance path;
A printing apparatus comprising:

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

It is a schematic diagram which shows an example of an apparatus structure with which the printing apparatus of this embodiment is provided. 1 is a block diagram illustrating an overall configuration of a printing apparatus according to a first embodiment. It is a figure which shows the structural example of the irradiation position change member in 1st Embodiment. It is a flowchart which shows the example of a procedure of the printing method of 1st Embodiment. FIG. 6 is a schematic diagram illustrating an operation example 1 in the printing apparatus according to the first embodiment. FIG. 6 is a schematic diagram illustrating an operation example 2 in the printing apparatus according to the first embodiment. It is a block diagram which shows the whole structure of the printing apparatus of 2nd Embodiment. It is a flowchart which shows the example of a procedure of the printing method of 2nd Embodiment. It is the schematic which shows the operation example 1 in the printing apparatus of 2nd Embodiment. It is the schematic which shows the operation example 2 in the printing apparatus of 2nd Embodiment. It is a block diagram which shows the whole structure of the printing apparatus of 3rd Embodiment. It is a flowchart which shows the example of a procedure of the printing method of 3rd Embodiment. It is the schematic which shows the operation example 1 in the printing apparatus of 3rd Embodiment. It is the schematic which shows the operation example 2 in the printing apparatus of 3rd Embodiment.

  At least the following matters will become clear from the description of the present specification and the accompanying drawings.

A printing apparatus that forms an image by ejecting ultraviolet curable ink onto a medium being conveyed through a conveyance path, and irradiating the ink landed on the medium with ultraviolet light from an ultraviolet light source. On the medium by the ultraviolet light source, a speed control unit that switches the medium transport speed between a first mode in which the predetermined speed is set and a second mode in which the medium transport speed is higher than the predetermined speed. By controlling the irradiation position changing member that changes the ultraviolet irradiation position and the irradiation position changing member in the first mode, the ultraviolet irradiation position is shifted from the predetermined position on the medium to the downstream side of the conveyance path in the first mode. And an irradiation position control unit that shifts the ultraviolet irradiation position upstream of the predetermined position on the medium in the transport path in the second mode. The one.
According to such a printing apparatus, it is possible to obtain an equivalent image quality between medium conveyance modes having different speeds in the printing apparatus.

In this printing apparatus, the irradiation position changing member includes a pivotable member that fixes a fulcrum at a predetermined position of the printing apparatus and determines an irradiation direction of the ultraviolet light source, and the irradiation position control It is desirable that the unit performs the transition of the ultraviolet irradiation position according to each mode by controlling the rotation of the bulk member in the irradiation position changing member.
According to such a printing apparatus, a simple and easy-to-install bristle member can be simply rotated via an ordinary rotating member having a pin fulcrum to control the irradiation direction of the ultraviolet light source. Can be performed efficiently.

A printing apparatus that discharges an ultraviolet curable ink to a medium that is being conveyed through a conveyance path and performs image formation by irradiating the ink that has landed on the medium with ultraviolet light from an ultraviolet light source. Includes a first irradiating unit that irradiates ultraviolet rays upstream from a predetermined position in the transport path, and a second irradiating unit that performs ultraviolet irradiation downstream from a predetermined position in the transport path, and a medium. A speed control unit that switches a medium transport speed between a first mode in which the transport speed of the medium is a predetermined speed and a second mode in which the transport speed of the medium is higher than the predetermined speed; An irradiation position control unit that drives the first irradiation unit in the mode, and drives the second irradiation unit in the second mode to perform switching control of the irradiation units. Printing equipment It will become apparent.
According to such a printing apparatus, it is possible to obtain an equivalent image quality between medium conveyance modes having different speeds in the printing apparatus.

A printing apparatus that discharges ultraviolet curable ink onto a medium that is being conveyed through a conveyance path and forms an image by irradiating the ink that has landed on the medium with ultraviolet light from an ultraviolet light source. A speed control unit that switches the medium transport speed between a first mode in which the speed is a predetermined speed and a second mode in which the medium transport speed is higher than the predetermined speed; and on the transport path By controlling the light source moving means for moving the ultraviolet light source and the light source moving means, the low-speed conveyance of the medium moves the ultraviolet light source to the downstream side of the conveyance path from a predetermined position on the medium. The printing apparatus is characterized by including an irradiation position control unit that moves the ultraviolet light source to the upstream side of the conveyance path from a predetermined position on the medium during conveyance.
According to such a printing apparatus, it is possible to obtain an equivalent image quality between medium conveyance modes having different speeds in the printing apparatus.

In this printing apparatus, the irradiation position control unit may determine the time from when the ink lands on the medium until the irradiation of the ultraviolet ray to the ink by the ultraviolet light source is started with the first mode and the first mode. It is desirable to execute the control as much as possible between the two modes.
According to such a printing apparatus, it is possible to obtain image quality with higher equivalence between medium conveyance modes having different speeds in the printing apparatus.

In addition, a printing apparatus that forms an image by ejecting ultraviolet curable ink onto a medium that is being conveyed through a conveyance path and irradiating the ink that has landed on the medium with ultraviolet light from an ultraviolet light source increases the conveyance speed of the medium. A speed control process for switching the medium conveyance speed between a first mode in which a predetermined speed is set and a second mode in which the medium conveyance speed is higher than the predetermined speed, and the medium on the medium by the ultraviolet light source. By controlling the irradiation position changing member that changes the ultraviolet irradiation position in the first mode, the ultraviolet irradiation position is shifted from the predetermined position on the medium to the downstream side of the transport path in the first mode, and in the second mode. The printing method is characterized by executing an irradiation position control process in which the ultraviolet irradiation position is shifted to the upstream side of the conveyance path from a predetermined position on the medium.
According to such a printing method, it is possible to obtain the same image quality between the medium transport modes having different speeds in the printing apparatus.

Further, in the printing apparatus that forms an image by ejecting ultraviolet curable ink onto the medium being conveyed through the conveyance path and irradiating the ink landed on the medium with ultraviolet light from the ultraviolet light source, the ultraviolet light source includes: A first irradiating unit that irradiates ultraviolet rays upstream from a predetermined position in the conveying path; and a second irradiating unit that irradiates ultraviolet rays downstream from a predetermined position in the conveying path. A speed control process for switching the medium transport speed between a first mode in which the speed is a predetermined speed and a second mode in which the medium transport speed is higher than the predetermined speed; and the first mode. Performing an irradiation position control process, which sometimes drives the first irradiation unit, and drives the second irradiation unit in the second mode to perform switching control of each irradiation unit. You A printing method become apparent.
According to such a printing method, it is possible to obtain the same image quality between the medium transport modes having different speeds in the printing apparatus.

In addition, a printing apparatus that forms an image by ejecting ultraviolet curable ink onto a medium that is being conveyed through a conveyance path and irradiating the ink that has landed on the medium with ultraviolet light from an ultraviolet light source increases the conveyance speed of the medium. A speed control process for switching the medium conveyance speed between a first mode in which a predetermined speed is set and a second mode in which the medium conveyance speed is higher than the predetermined speed, and the ultraviolet light on the conveyance path. By controlling the light source moving means for moving the light source, the ultraviolet light source is moved downstream from the predetermined position on the medium when the medium is transported at a low speed, and the predetermined position on the medium is transported when the medium is transported at a high speed. A printing method characterized by performing an irradiation position control process for moving the ultraviolet light source further to the upstream side of the conveyance path is clarified.
According to such a printing method, it is possible to obtain the same image quality between the medium transport modes having different speeds in the printing apparatus.

=== Embodiment ===
<About the configuration of the printing device>
FIG. 1 is a schematic diagram illustrating an example of an apparatus configuration included in the printing apparatus according to the present embodiment. The printing apparatus, that is, the printer 1 in this embodiment is an apparatus that prints an image on a medium such as paper, cloth, or film, and is communicably connected to an external apparatus (FIG. 4: computer 200). In the present embodiment, as an example of a medium on which the printer 1 records an image, a paper wound in a roll shape (hereinafter referred to as a sheet 5 (continuous paper)) will be described. In the following description, the surface of the sheet 5 on which printing is performed (that is, the side facing the head) is referred to as the front surface, and the surface on which printing is not performed is referred to as the back surface.

  As shown in FIG. 1, in the printer 1, the above-described sheet 5 having both ends wound around the feeding shaft 20 and the winding shaft 25 in a roll shape is stretched between the feeding shaft 20 and the winding shaft 25. The sheet 5 is conveyed from the feeding shaft 20 to the winding shaft 25 along the path 8 thus stretched. In the printer 1, an image is recorded on the sheet 5 conveyed along the conveyance path 8.

  The types of the sheet 5 include a paper system such as high-quality paper, cast paper, art paper, and coated paper, and a film system such as synthetic paper, PET (Polyethylene terephthalate), and PP (Polypropylene). Moreover, although the sheet 5 was mentioned as an example as a medium, it is not limited to this, For example, a cut paper, a film, and cloth may be sufficient.

  As shown in FIG. 1, the printer 1 winds a sheet 5 fed from a feeding shaft 20 around a platen drum 30, and an image is formed on the sheet 5 by operation of heads spaced apart by a predetermined distance on the platen drum 30. It has a mechanism to record. The sheet 5 on which the image is recorded is wound around the winding shaft 25 and discharged to the rear of the path.

  The mechanism for feeding the sheet 5 includes a feeding shaft 20 around which the end of the sheet 5 is wound, and a driven roller 21 around which the sheet 5 drawn from the feeding shaft 20 is wound. The feeding shaft 20 supports the end of the sheet 5 by winding it with the surface of the sheet 5 facing outward. When the feeding shaft 20 rotates clockwise on the paper surface of FIG. 1, the sheet 5 wound around the feeding shaft 20 is fed toward the platen drum 30 via the driven roller 21. The sheet 5 is set on the feeding shaft 20 via a core tube (not shown) that is detachable from the feeding shaft 20. Therefore, when all the sheets 5 on the feeding shaft 20 are fed toward the platen drum 30, a new core tube around which the roll-shaped sheet 5 is wound is attached to the feeding shaft 20, and the sheet on the feeding shaft 20 is mounted. 5 can be replaced.

  On the other hand, the sheet 5 fed out as described above is supported by the platen drum 30 and by the heads 51 and 52 disposed along the outer peripheral surface of the platen drum 30 and UV lamps 61 to 63 as ultraviolet light sources. A predetermined process is performed, and an image is recorded on the surface. In such a mechanism for image formation, a front drive roller 31 and a rear drive roller 32 provided on both sides of the platen drum 30 are provided, and the sheet 5 conveyed from the front drive roller 31 to the rear drive roller 32 is transferred to the platen. It is supported by the drum 30 and receives an image recording process.

  Among these, the front drive roller 31 has a plurality of minute protrusions formed by thermal spraying on the outer peripheral surface, and winds the sheet 5 fed from the feeding shaft 20 from the back side. The front drive roller 31 rotates clockwise on the paper surface of FIG. 1 to convey the sheet 5 fed from the feeding shaft 20 to the downstream side of the conveyance path.

  A nip roller 31 n is provided for the front drive roller 31. The nip roller 31 n is in contact with the surface of the sheet 5 while being biased toward the front drive roller 31, and sandwiches the sheet 5 with the front drive roller 31. Thereby, the frictional force between the front drive roller 31 and the sheet 5 is ensured, and the sheet 5 can be reliably conveyed by the front drive roller 31.

  The platen drum 30 is a cylindrical drum that is rotatably supported by a predetermined support mechanism (not shown), and winds the sheet 5 conveyed from the front drive roller 31 to the rear drive roller 32 from the back side. Multiply. The platen drum 30 supports the sheet 5 from the back side while receiving the frictional force between the plate 5 and rotating in the conveyance direction Rs of the sheet 5. In addition, driven rollers 33 and 34 for folding the sheet 5 are provided on both sides of the portion around the platen drum 30. Of these, the driven roller 33 wraps the surface of the sheet 5 between the front drive roller 31 and the platen drum 30 to fold the sheet 5 back. On the other hand, the driven roller 34 wraps the surface of the sheet 5 between the platen drum 30 and the rear drive roller 32 and folds the sheet 5. In this way, by folding the sheet 5 on the upstream side and the downstream side in the transport direction Rs with respect to the platen drum 30, a long winding portion of the sheet 5 around the platen drum 30 can be secured.

  Further, the rear drive roller 32 has a plurality of minute projections formed by thermal spraying on the outer peripheral surface, and winds the sheet 5 conveyed from the platen drum 30 via the driven roller 34 from the back surface side. The rear drive roller 32 conveys the sheet 5 toward the take-up shaft 25 by rotating clockwise on the paper surface of FIG. A nip roller 32n is provided for the rear drive roller 32. The nip roller 32 n is in contact with the surface of the sheet 5 while being urged toward the rear drive roller 32, and sandwiches the sheet 5 with the rear drive roller 32. Thereby, the frictional force between the rear drive roller 32 and the sheet 5 is ensured, and the sheet 5 can be reliably conveyed by the rear drive roller 32.

  A plurality of heads 51 for recording color images on the surface of the sheet 5 designated by the platen drum 30 are provided on the outer peripheral surface of the platen drum 30 that designates the sheet 5 in this manner. The plurality of heads 51 correspond to different colors, specifically, four heads 51 corresponding to yellow, cyan, magenta, and black. The heads 51 and the like are arranged in the transport direction Rs in the above-described color order.

  Each of the heads 51 described above is opposed to the surface of the sheet 5 wound around the platen drum 30 with a slight clearance, and ejects the corresponding color ink by an ink jet method. Then, each head 51 ejects ink to the sheet 5 conveyed in the conveyance direction Rs, whereby a color image is formed on the surface of the sheet 5. Incidentally, the nozzles of the heads 51 and 52 are respectively provided with corresponding piezoelectric elements. Then, when a controller 100 that controls the printing apparatus 1 applies a drive signal to the piezo element, ink is ejected from the nozzle corresponding to the piezo element.

  As the ink ejected by the heads 51 and the like, UV (ultraviolet) ink (photocurable ink) that is cured by irradiating ultraviolet rays (light) is used. Therefore, UV lamps 61 and 62 are provided along the outer peripheral surface of the platen drum 30 in order to cure the ink discharged from the head 51 and landed on the surface of the sheet 5 and fix the ink to the sheet 5.

  The ink curing process is performed in two stages, temporary curing and main curing. A temporary curing UV lamp 61 is arranged between each of the plurality of heads 51. That is, the UV lamp 61 irradiates weak ultraviolet rays to cure (temporarily cure) the ink to such an extent that the shape of the ink does not collapse, and does not completely cure the ink. On the other hand, a UV lamp 62 for main curing is provided downstream of the plurality of heads 51 in the transport direction Rs. That is, the UV lamp 62 irradiates ultraviolet rays stronger than the UV lamp 61 to completely cure (main cure) the ink. In this way, the color image formed by the plurality of heads 51 can be fixed on the surface of the sheet 5 by executing the ink temporary curing and the main curing stepwise.

  Further, a head 52 is provided downstream of the UV lamp 62 in the transport direction Rs. The head 52 is opposed to the surface of the sheet 5 wound around the platen drum 30 with a slight clearance, and discharges transparent UV ink onto the surface of the sheet 5 by an ink jet method. That is, the transparent ink is further ejected from the color image formed by the heads 51 for four colors. Further, a UV lamp 63 is provided downstream of the head 52 in the transport direction Rs. The UV lamp 63 completely cures (mainly cures) the transparent ink landed on the surface of the sheet 5 by the head 52 by irradiating with strong ultraviolet rays. Thereby, the transparent ink can be fixed on the surface of the sheet 5.

  As described above, the sheet 5 wound and supported on the outer peripheral surface of the platen drum 30 is provided with heads 51 and 52 and UV lamps 61, 62 and 63 provided so as to face the winding portion Ra of the platen drum 30. Each functional unit performs each process of discharging and curing ink on the sheet surface, and forms a color image coated with transparent ink. Then, the sheet 5 on which the color image is formed is conveyed toward the take-up shaft 25 by the rear drive roller 32.

  The sheet 5 on which image formation has been performed as described above is wound and supported by the winding shaft 25 with its surface facing outward. A driven roller 47 that winds the sheet 5 from the back side is provided between the winding shaft 25 and the rear driving roller 32. When the winding shaft 25 rotates clockwise on the paper surface of FIG. 1, the sheet 5 conveyed from the rear drive roller 32 is wound around the winding shaft 25 via the driven roller 47. The sheet 5 is wound around the winding shaft 25 via a core tube (not shown) that is detachable from the winding shaft 25. Therefore, when the sheet 5 taken up with respect to the core tube set on the take-up shaft 25 exceeds a specified amount, it is possible to remove the sheet 5 together with the core tube. The above is the outline of the device configuration of the printer 1.

  Subsequently, an electrical configuration for controlling the printer 1 will be described. FIG. 2A is a block diagram showing the overall configuration of the printing apparatus according to the first embodiment. Specifically, the electrical configuration of the printer 1 that can change the irradiation position of the ultraviolet light on the sheet 5 by the UV lamp 61. It is a block diagram which shows typically. In FIG. 2A, the printer 1 that can change the irradiation position of the ultraviolet light on the sheet 5 by the UV lamp 61 is illustrated as the first embodiment, but the ultraviolet light is also used in each embodiment described below. The configuration other than the configuration (the rotation unit 80) that can change the irradiation position is common.

  The printer 1 described above is controlled by a computer 200 shown in FIG. 2A. The computer 200 includes a printer driver, can display a user interface on a display device (not shown), and can convert image data output from an application program into print data. Then, the computer 200 outputs print data corresponding to the image to be printed to the printer 1 in order to cause the printer 1 to print the image.

  On the other hand, the printer 1 is provided with a controller 100 that controls each unit of the printer 1 in accordance with a command from the computer 200. Each part of the apparatus such as the head, UV lamp, and sheet conveying system is controlled by the controller 100. The controller 100 includes an interface unit 104, a CPU 103, a memory 101, and a unit control circuit 105 that are connected to each other via an internal bus 106.

  The interface unit 104 transmits and receives data between the computer 200 as an external device and the printer 1. The CPU 103 is an arithmetic processing device for controlling the entire printer. The memory 101 is for securing an area for storing a program of the CPU 103, a work area, and the like, and includes storage elements such as a RAM and an EEPROM. The CPU 103 controls each unit via the unit control circuit 105 according to the program 102 stored in the memory 101.

  The units controlled by the unit control circuit 105 via the external bus 107 include a transport unit 40 (such as a motor for transporting the sheet 5), a head unit 50 (heads 51 and 52), and an irradiation unit 60 (UV lamps 61 to 61). 63), a detector group 70 (sensors for detecting rotation and tension of the drum), and a rotation unit 80 are included.

  The printer 1 that has received the print data from the computer 200 as an external device controls each unit (the transport unit 20, the head unit 30, the irradiation unit 40, and the rotation unit 80) by the controller 100 via the unit control circuit 105. The image is printed on the medium according to the print data.

  The controller 100 controls each unit based on the print data received from the computer 200 and prints an image on the sheet 5. The situation in the printer 1 is monitored by a detector group 70, and the detector group 70 outputs a detection result to the controller 100. The controller 100 controls each unit based on the detection result output from the detector group 70. The detector group 70 includes a drum encoder 71, tension sensors 72 to 74, an edge sensor 75, and the like.

  The details of the control of the controller 100 for each part of the apparatus are as follows. The controller 100 controls the ink ejection timing of each head 51 that forms a color image according to the conveyance of the sheet 5. Specifically, the control of the ink ejection timing is executed based on the output (detection value) of a drum encoder 71 that is attached to the rotation shaft of the platen drum 30 and detects the rotation position of the platen drum 30. That is, since the platen drum 30 is driven to rotate as the sheet 5 is conveyed, the conveyance position of the sheet 5 can be grasped by referring to the output of the drum encoder 71 that detects the rotational position of the platen drum 30. Therefore, the controller 100 generates a pts (print timing signal) signal from the output of the drum encoder 71, and controls the ink ejection timing of each recording head 51 based on the pts signal, so that the ink ejected by each head 51 is obtained. Is landed on the target position of the conveyed sheet 5 to form a color image.

  Similarly, the timing at which the head 52 discharges the transparent ink is also controlled by the controller 100 based on the output of the drum encoder 71. Thereby, it is possible to accurately eject the transparent ink to the color image formed by the plurality of heads 51. Further, the controller 100 also controls the timing of turning on / off the UV lamps 61, 62, and 63 and the amount of irradiation light.

  Further, the controller 100 controls a function of controlling the conveyance of the sheet 5 described in detail with reference to FIG. That is, motors are connected to the feeding shaft 20, the front drive roller 31, the rear drive roller 32, and the take-up shaft 25 among members constituting the sheet conveyance system. The controller 100 controls the conveyance of the sheet 5 by controlling the speed and torque of each motor while rotating these motors. Details of the conveyance control of the sheet 5 are as follows.

  The controller 100 rotates the feeding motor 41 that drives the feeding shaft 20 and supplies the sheet 5 from the feeding shaft 20 to the front drive roller 31. At this time, the controller 100 controls the torque of the feeding motor 41 to adjust the tension (feeding tension Ta) of the sheet 5 from the feeding shaft 20 to the front drive roller 31. That is, a tension sensor 72 that detects the feeding tension Ta is attached to the driven roller 21 disposed between the feeding shaft 20 and the front drive roller 31. The tension sensor 72 can be configured by a load cell that detects a force received from the seat 5, for example. Based on the detection result of the tension sensor 72, the controller 100 feedback-controls the torque of the feeding motor 41 to adjust the feeding tension Ta of the sheet 5.

  At this time, the controller 100 feeds the sheet 5 while adjusting the position of the sheet 5 supplied from the feed shaft 20 to the front drive roller 31 in the width direction (the direction orthogonal to the paper surface of FIG. 1). That is, the printer 1 is provided with the steering unit 45 that displaces the feeding shaft 20 and the driven roller 21 in the axial direction (in other words, the width direction of the sheet 5). Further, an edge sensor 75 that detects an end of the sheet 5 in the width direction is disposed between the driven roller 21 and the front drive roller 31. The edge sensor 75 can be composed of a distance sensor such as an ultrasonic sensor, for example. Then, the controller 100 performs feedback control of the steering unit 45 based on the detection result of the edge sensor 75 to adjust the position of the seat 5 in the width direction. As a result, the position of the sheet 5 in the width direction is optimized, and conveyance failures such as meandering of the sheet 5 are suppressed.

  Further, the controller 100 rotates the front drive motor 42 that drives the front drive roller 31 and the rear drive motor 43 that drives the rear drive roller 32. As a result, the sheet 5 fed from the feeding unit 2 passes through the process unit 3. At this time, speed control is executed for the front drive motor 42, while torque control is executed for the rear drive motor 43. That is, the controller 100 adjusts the rotational speed of the front drive motor 42 to be constant based on the encoder output of the front drive motor 42. Accordingly, the sheet 5 is conveyed at a constant speed by the front drive roller 31.

  On the other hand, the controller 100 controls the torque of the rear drive motor 43 to adjust the tension (process tension Tb) of the sheet 5 from the front drive roller 31 to the rear drive roller 32. That is, the tension sensor 73 for detecting the process tension Tb is attached to the driven roller 34 disposed between the platen drum 30 and the rear drive roller 32. The tension sensor 73 can be constituted by a load cell that detects a force received from the seat 5, for example. In this way, the tension of the sheet 5 away from the platen drum 30 (the winding portion Ra thereof) toward the rear drive roller 32 is detected by the tension sensor 73. The controller 100 adjusts the process tension Tb of the seat 5 by feedback controlling the torque of the rear drive motor 43 based on the detection result of the tension sensor 73.

  Further, the controller 100 rotates the winding motor 44 that drives the winding shaft 25, and winds the sheet 5 conveyed by the rear driving roller 32 around the winding shaft 25. At this time, the controller 100 adjusts the tension (winding tension Tc) of the sheet 5 from the rear drive roller 32 to the winding shaft 40 by controlling the torque of the winding motor 44. That is, a tension sensor 74 that detects the winding tension Tc is attached to the driven roller 47 disposed between the rear drive roller 32 and the winding shaft 25. The tension sensor 74 can be constituted by a load cell that detects a force received from the seat 5, for example. Then, the controller 100 adjusts the winding tension Tc of the sheet 5 by feedback controlling the torque of the winding motor 44 based on the detection result of the tension sensor 74. Specifically, the controller 100 decreases the winding tension Tc in accordance with an increase in the diameter of the roll made of the sheet 5 wound around the winding shaft 25. Thus, the sheet 5 is controlled so that the pressure of the sheet 5 near the center of the roll becomes excessive and the sheet 5 is not damaged as the roll diameter increases.

<Configuration Specific to First Embodiment>
When the reception speed of the image forming data from the computer 200 in the interface unit 104 is faster than a predetermined reference, the image forming process in the printer 1 can be continuously executed in accordance with the data reception. When the speed is slower than a predetermined reference, it is necessary to continue the process of storing received data in a buffer or the like until a predetermined processing unit is reached. In that case, the controller 100 performs control to reduce the conveyance speed of the sheet 5 in order to suppress the processing speed of image formation. Therefore, the controller 100 selectively selects two operation modes: a first mode in which the sheet 5 is conveyed at a low speed (eg, 7.5 m / min) and a second mode in which the sheet 5 is conveyed at a high speed (eg, 15 m / min). It has a configuration that can be executed.

  For this reason, the speed control unit 110 of the controller 100 monitors the data reception speed at the interface unit 104, and when this monitored value is below a predetermined reference, the unit control is performed based on the encoder output of the front drive motor 42. Via the circuit 105, the above-mentioned front drive motor 42 is instructed to rotate at a low speed (for example, 7.5 m / min) corresponding to the first mode. On the other hand, when the data reception speed at the interface unit 104 exceeds a predetermined reference, the controller 100 determines the above-mentioned front drive motor 42 via the unit control circuit 105 based on the encoder output of the front drive motor 42. Instruct to rotate at a high speed (for example, 15 m / min) corresponding to the second mode. Of course, the same torque control as described above is executed for the rear drive motor 43. Thus, the sheet 5 is conveyed by the front driving roller 31 at a predetermined speed corresponding to each of the first and second modes. The speed control unit 110 is a functional unit that is implemented when the CPU 103 executes the program 102.

  In the printer 1 that performs such speed control, since the distance between the head 51 that ejects ink and the UV lamp 61 is constant, irradiation of ultraviolet rays by the UV lamp 61 starts after the ink has landed on the sheet 5. The time until it is determined depends on the conveyance speed of the sheet 5. That is, the time required to start the irradiation of ultraviolet rays to the ink differs between the above-described two operation modes.

  On the other hand, the ink described above has a property of spreading and spreading on the sheet 5 until it is cured by ultraviolet rays. If the operation mode is changed and executed, the state of wetting and spreading on the sheet 5 is the operation mode. This is a situation where the image quality of the image formed on the sheet 5 is different between the operation modes.

  Therefore, as a configuration unique to the printer 1 of the first embodiment, there is provided a bulk member 80 (irradiation position changing member) for changing the ultraviolet irradiation position on the sheet 5 by the UV lamp 61 described above, and a configuration for controlling this. It has. FIG. 2B is a diagram illustrating a configuration example of a bulk member 80 that is an irradiation position changing member according to the first embodiment. The umbrella member 80 is a member that is provided in a lighting fixture such as a light bulb and has a structure similar to a conventional light bulb umbrella that narrows the light beam direction, and accommodates the UV lamp 61 in its inner empty top portion 82. In addition, the pin member 80 fixes the pin fulcrum 84 of the top 83 to a predetermined location 85 near the platen drum 30 and is rotated by a rotation motor 81 provided on the pin fulcrum 84 so that a so-called swinging operation is possible. It is a member. If such a swinging operation is performed, the irradiation direction of the ultraviolet light in the UV lamp 61 accommodated in the inner empty top portion 82 can be arbitrarily controlled.

<Specific Control in Printer 1 of First Embodiment>
Next, a process for controlling the ultraviolet irradiation position on the sheet 5 in accordance with the first and second modes by controlling the above-described bulk member 80 will be described. FIG. 3 is a flowchart showing an example of the procedure of the printing method of the first embodiment, FIG. 4 is a schematic diagram showing an operation example 1 in the printing apparatus of the first embodiment, and FIG. 5 is in the printing apparatus of the first embodiment. It is the schematic which shows the operation example 2. FIG. The process described below is executed by the irradiation position control unit 111 of the printer 1. The irradiation position control unit 111 is a functional unit that is mounted when the CPU 103 executes the program 102.

  In this case, the speed control unit 110 described above monitors the data reception speed from the computer 200 in the interface unit 104, and in accordance with the comparison result between the monitored value and a predetermined reference, Any mode is selected and executed.

  On the other hand, the irradiation position control unit 111 of the controller 100 receives the execution notification of the first and second modes from the speed control unit 110 (s100), and the mode to be executed is either the first or the second mode. It is determined whether the mode is selected (s101). When the mode to be executed is the first mode, that is, when high-speed conveyance of the sheet 5 is executed (s101: high-speed), the irradiation position control unit 111 passes the external motor 107 with respect to the rotation motor 81 in the bulk member 80. Then, a control signal corresponding to the rotation amount of a predetermined angle is given (s102).

  Upon receiving the control signal, the rotation motor 81 rotates in accordance with the control signal, whereby the bulk member 80 swings around the pin fulcrum 84 toward the downstream side of the conveyance path (s103). ). Since the UV lamp 61 is accommodated in the inner empty top portion 82 of the cap member 80 that has been swung, the direction of the ultraviolet light flux by the UV lamp 61 is also set in the direction after the swing of the cap member 80. . Thereby, the ultraviolet irradiation position 13 by the UV lamp 61 is shifted from the predetermined position 12 on the sheet 5 to the downstream side of the conveyance path (s104).

  In such a state, as shown in FIG. 4, the controller 100 controls the head 51 via the external bus 107 to land ink on the sheet 5, and after a predetermined time t has elapsed, that is, the sheet 5 has landed ink. The UV lamp 61 is caused to emit light at a timing when it is conveyed at a high speed from the position 11 by a distance Df. The ultraviolet rays generated by the light emitted from the UV lamp 61 are applied to the ink 10 at the ultraviolet irradiation position 13 on the sheet 5, and the ink 10 is cured.

  On the other hand, when the mode executed by the speed control unit 110 is the second mode, that is, when low-speed conveyance of the sheet 5 is executed (s101: low speed), the irradiation position control unit 111 of the controller 100 A control signal corresponding to the rotation amount of a predetermined angle in the opposite direction to that in the first mode is given to the rotation motor 81 via the external bus 107 (s105).

  Upon receiving the control signal, the rotation motor 81 rotates in accordance with the control signal, whereby the bulk member 80 swings around the pin fulcrum 84 toward the upstream side of the conveyance path (s106). ). Since the UV lamp 61 is accommodated in the inner empty top portion 82 of the cap member 80 that has been swung, the direction of the ultraviolet light flux by the UV lamp 61 is also set in the direction after the swing of the cap member 80. . Thereby, the ultraviolet irradiation position 13 by the UV lamp 61 is shifted from the predetermined position 12 on the sheet 5 to the upstream side of the conveyance path (s107).

  In such a state, as shown in FIG. 5, the controller 100 controls the head 51 via the external bus 107 to land ink on the sheet 5, and the same predetermined time t as when the first mode is executed. In other words, the UV lamp 61 is caused to emit light at a timing when the sheet 5 is conveyed at a low speed from the ink landing position 11 by the distance Ds (Ds <Df). The ultraviolet rays generated by the light emitted from the UV lamp 61 are applied to the ink 10 at the ultraviolet irradiation position 13 on the sheet 5, and the ink 10 is cured.

  As described above, in both the high-speed conveyance mode and the low-speed conveyance mode of the sheet 5, the time t from when the ink 10 has landed on the sheet 5 until the irradiation of ultraviolet rays by the UV lamp 61 is started, that is, the ink 10. Is controlled so that the curing start time by ultraviolet rays becomes equal. Therefore, even when the above-described first and second operation modes are switched and executed, the state of the ink 10 wet and spread on the sheet 5 and the image quality of the image formed on the sheet 5 are different between the operation modes. It becomes the same quality.

As described above, the printing apparatus 1 of the present embodiment is
A printing apparatus 1 that forms an image by ejecting ultraviolet curable ink onto a medium 5 being conveyed through a conveyance path, and irradiating the ink 10 landed on the medium 5 with ultraviolet light from an ultraviolet light source 61,
A speed control unit 110 that switches the medium conveyance speed between a first mode in which the conveyance speed of the medium 5 is set to a predetermined speed and a second mode in which the conveyance speed of the medium 5 is higher than the predetermined speed; ,
An irradiation position changing member 80 for changing an ultraviolet irradiation position on the medium 5 by the ultraviolet light source 61;
By controlling the irradiation position changing member 80, the ultraviolet irradiation position is shifted from the predetermined position on the medium 5 to the downstream side of the conveyance path in the first mode, and on the medium 5 in the second mode. An irradiation position control unit 111 that shifts the ultraviolet irradiation position to the upstream side of the conveyance path from a predetermined position;
It has.
By adopting such a configuration, it is possible to obtain the same image quality between the medium transport modes having different speeds in the printing apparatus.

<Configuration Specific to Second Embodiment>
Unlike the case of the first embodiment described above, a mode in which the UV lamp 61 includes two irradiation units can be assumed. FIG. 6 is a block diagram illustrating the overall configuration of the printing apparatus according to the second embodiment. As a configuration unique to the printer 1 of the second embodiment, the UV lamp 61 includes a first irradiation unit 64 and a second irradiation unit 65 in order to change the ultraviolet irradiation position 13 on the sheet 5 by the UV lamp 61 described above. These two irradiation parts are provided, and the structure which controls this is provided.

  The first irradiation unit 64 in the UV lamp 61 includes an ultraviolet irradiation position 13 on the upstream side of the predetermined position 12 in the sheet 5, and the second irradiation unit 65 is on the downstream side of the predetermined position 12 in the sheet 5. An ultraviolet irradiation position 13 is provided (FIGS. 8 and 9).

  In this case, the controller 100 of the printer 1 instructs the irradiation units 64 and 65 of the UV lamp 61 through the unit control circuit 105 and the external bus 107 at a predetermined timing for each mode. Each irradiation unit 64 and 65 is connected to the controller 100 via the external bus 107, and can receive light emission control by the controller 100 separately.

<Specific Control in Printer 1 of Second Embodiment>
Subsequently, the ultraviolet irradiation position 13 on the sheet 5 is controlled according to the first and second modes by controlling the light emission of the first irradiation unit 64 and the second irradiation unit 65 in the UV lamp 61 described above. Processing will be described. FIG. 7 is a flowchart showing an example of the procedure of the printing method of the second embodiment, FIG. 8 is a schematic diagram showing an operation example 1 in the printing apparatus of the second embodiment, and FIG. 9 is in the printing apparatus of the second embodiment. It is the schematic which shows the operation example 2. FIG. The process described below is executed by the irradiation position control unit 111 of the printer 1. The irradiation position control unit 111 is a functional unit that is mounted when the CPU 103 executes the program 102.

  In this case, the speed control unit 110 described above monitors the data reception speed from the computer 200 in the interface unit 104, and in accordance with the comparison result between the monitored value and a predetermined reference, Any mode is selected and executed.

  On the other hand, the irradiation position control unit 111 of the controller 100 receives the execution notification of the first and second modes from the speed control unit 110 (s200), and the mode to be executed is either the first or the second mode. It is determined whether the mode is selected (s201). When the mode to be executed is the first mode, that is, when high-speed conveyance of the sheet 5 is executed (s201: high speed), the irradiation position control unit 111 waits to give a light emission instruction to the second irradiation unit 65 in the UV lamp 61 The state is taken (s202).

  In such a state, as shown in FIG. 8, the controller 100 controls the head 51 via the external bus 107 to land ink on the sheet 5, and after a predetermined time t has elapsed, that is, the sheet 5 has landed ink. At the timing at which the distance Df is conveyed at a high speed from the position 11 (s203: y), a light emission instruction is given to the second irradiation unit 65 (s204), and ultraviolet light is emitted (s205). The ultraviolet rays generated by the light emission of the second irradiation unit 65 are applied to the ink 10 at the ultraviolet irradiation position 13 on the downstream side of the conveyance path from the predetermined position 12 on the sheet 5, and the ink 10 is cured.

  On the other hand, the irradiation position control unit 111 of the controller 100 is the irradiation position control unit when the mode executed by the speed control unit 110 is the second mode, that is, when the sheet 5 is conveyed at low speed (s201: low speed). 111 is in a standby state for giving a light emission instruction to the first irradiation unit 64 in the UV lamp 61 (s206).

  In this state, as shown in FIG. 9, the controller 100 controls the head 51 via the external bus 107 to land ink on the sheet 5, and after a predetermined time t has elapsed, that is, the sheet 5 has landed ink. At a timing at which the distance Ds is conveyed at a low speed from the position 11 (s207: y), a light emission instruction is given to the first irradiation unit 64 (s208), and ultraviolet light is emitted (s209). The ultraviolet rays generated by the light emission of the first irradiation unit 64 are applied to the ink 10 at the ultraviolet irradiation position 13 on the upstream side of the conveyance path from the predetermined position 12 on the sheet 5, and the ink 10 is cured.

  As described above, in both the high-speed conveyance mode and the low-speed conveyance mode of the sheet 5, irradiation of ultraviolet rays is started by the irradiation units 64 and 65 of the UV lamp 61 after the ink 10 has landed on the sheet 5. Is controlled so as to equalize the time t until the ink is cured, that is, the curing start time of the ink 10 by ultraviolet rays. Therefore, even when the above-described first and second operation modes are switched and executed, the state of the ink 10 wet and spread on the sheet 5 and the image quality of the image formed on the sheet 5 are different between the operation modes. It becomes the same quality.

As described above, the printing apparatus 1 of the present embodiment is
In this printing apparatus, an ultraviolet curable ink 10 is ejected onto a sheet 5 being conveyed through a conveyance path, and ultraviolet rays are applied to the ink 10 landed on the sheet 5 by UV lamps 61 to 63. And
The UV lamp 61 includes a first irradiation unit 64 that performs ultraviolet irradiation on the upstream side of the predetermined position 12 in the conveyance path, and a second irradiation unit 65 that performs ultraviolet irradiation on the downstream side of the predetermined position 12 in the conveyance path. Is,
A speed controller 110 that switches the medium conveyance speed between a first mode in which the conveyance speed of the sheet 5 is set to a predetermined speed and a second mode in which the conveyance speed of the sheet 5 is higher than the predetermined speed; ,
An irradiation position control unit 111 that drives the first irradiation unit 64 in the first mode and drives the second irradiation unit 65 in the second mode to perform switching control of the irradiation units 64 and 65 is provided.
By adopting such a configuration, it is possible to obtain the same image quality between the medium transport modes having different speeds in the printing apparatus.

<Configuration Specific to Third Embodiment>
In addition, unlike the first and second embodiments described above, a mode in which the UV lamp 61 moves on the conveyance path of the sheet 5 to change the ultraviolet irradiation position 13 can be assumed. FIG. 10 is a block diagram illustrating the overall configuration of the printing apparatus according to the third embodiment. As a configuration unique to the printer 1 of the third embodiment, in order to change the ultraviolet irradiation position 13 on the sheet 5 by the UV lamp 61 described above, the UV lamp 61 includes a light source moving unit 90 that moves on the conveyance path. It is equipped with the structure which controls this.

  The light source moving means 90 provided in the UV lamp 61 is a mechanism that slides the UV lamp 61 between the ultraviolet irradiation position 13 upstream of the predetermined position 12 and the ultraviolet irradiation position 13 downstream of the predetermined position 12 in the sheet 5. (FIGS. 8 and 9). What is necessary is just to employ | adopt what is called a rack and pinion as such a mechanism. In this case, the controller 100 performs control to drive the pinion 92, which is a small-diameter circular gear, by the light source moving motor 91 by a predetermined number of rotations and horizontally move the rack 93 by a predetermined distance according to the number of rotations of the pinion 92.

<Specific Control in Printer 1 of Third Embodiment>
Next, a process for controlling the ultraviolet light irradiation position 13 on the sheet 5 in accordance with the first and second modes by controlling the light source moving means 90 described above will be described. FIG. 11 is a flowchart showing a procedure example of the printing method of the third embodiment, FIG. 12 is a schematic diagram showing an operation example 1 in the printing apparatus of the third embodiment, and FIG. 13 is a printing of the third embodiment. It is the schematic which shows the operation example 2 in an apparatus. The process described below is executed by the irradiation position control unit 111 of the printer 1. The irradiation position control unit 111 is a functional unit that is mounted when the CPU 103 executes the program 102.

  In this case, the speed control unit 110 described above monitors the data reception speed from the computer 200 in the interface unit 104, and in accordance with the comparison result between the monitored value and a predetermined reference, Any mode is selected and executed.

  On the other hand, the irradiation position control unit 111 of the controller 100 receives the execution notification of the first and second modes from the speed control unit 110 (s300), and the mode to be executed is either the first or second mode. It is determined whether the mode is selected (s301). When the mode to be executed is the first mode, that is, when high-speed conveyance of the sheet 5 is executed (s301: high speed), the irradiation position control unit 111 connects the external bus 107 to the light source moving motor 91 in the light source moving unit 90. Then, a control signal corresponding to the predetermined rotation speed is given (s302).

  In response to the control signal, the light source moving motor 91 rotates in accordance with the control signal to drive the pinion 92, thereby moving the rack 93 horizontally by a predetermined distance and fixing the UV to the rack 93. The lamp 61 is shifted to the downstream side of the transport path (s303).

  In such a state, as shown in FIG. 12, the controller 100 controls the head 51 via the external bus 107 to land ink on the sheet 5, and after a predetermined time t has passed (s304: y), that is, The UV lamp 61 is caused to emit light at a timing when the sheet 5 is conveyed at a high speed by the distance Df from the ink landing position 11 (s305). The ultraviolet rays generated by the light emitted from the UV lamp 61 are applied to the ink 10 at the ultraviolet irradiation position 13 on the sheet 5, and the ink 10 is cured.

  On the other hand, the irradiation position control unit 111 of the controller 100 is the irradiation position control unit when the mode executed by the speed control unit 110 is the second mode, that is, when the sheet 5 is conveyed at low speed (s301: low speed). 111 gives a control signal corresponding to a predetermined rotational speed opposite to that in the first mode to the light source moving motor 91 in the light source moving means 90 via the external bus 107 (s306).

  In response to the control signal, the light source moving motor 91 rotates in accordance with the control signal to drive the pinion 92, thereby moving the rack 93 horizontally by a predetermined distance and fixing the UV to the rack 93. The lamp 61 is shifted to the upstream side of the conveyance path (s307).

  In such a state, as shown in FIG. 13, the controller 100 controls the head 51 via the external bus 107 to land ink on the sheet 5, and after a predetermined time t has passed (s308: y), that is, The UV lamp 61 is caused to emit light at a timing when the sheet 5 is conveyed at a low speed from the ink landing position 11 by a distance Ds (Ds <Df) (s309). The ultraviolet rays generated by the light emitted from the UV lamp 61 are applied to the ink 10 at the ultraviolet irradiation position 13 on the sheet 5, and the ink 10 is cured.

  As described above, in both the high-speed conveyance mode and the low-speed conveyance mode of the sheet 5, the time t from when the ink 10 has landed on the sheet 5 until the irradiation of ultraviolet rays by the UV lamp 61 is started, that is, the ink 10. Is controlled so that the curing start time by ultraviolet rays becomes equal. Therefore, even when the above-described first and second operation modes are switched and executed, the state of the ink 10 wet and spread on the sheet 5 and the image quality of the image formed on the sheet 5 are different between the operation modes. It becomes the same quality.

As described above, the printing apparatus 1 of the present embodiment is
A printing apparatus that discharges ultraviolet curable ink 10 onto a sheet 5 being conveyed on a conveyance path, and performs image formation by irradiating the ink 10 landed on the sheet 5 with ultraviolet rays from UV lamps 61 to 63. ,
A speed controller 110 that switches the medium conveyance speed between a first mode in which the conveyance speed of the sheet 5 is set to a predetermined speed and a second mode in which the conveyance speed of the sheet 5 is higher than the predetermined speed; ,
A light source moving means 90 for moving the UV lamp 61 on the transport path;
By controlling the light source moving means 90, the UV lamp 61 is moved to the downstream side of the conveyance path from the predetermined position 12 on the sheet 5 when the sheet 5 is conveyed at low speed, and the predetermined position on the sheet 5 is conveyed when the sheet 5 is conveyed at high speed. 12, an irradiation position control unit 111 that moves the UV lamp 61 to the upstream side of the conveyance path,
It has.
By adopting such a configuration, it is possible to obtain the same image quality between the medium transport modes having different speeds in the printing apparatus.

=== Other Embodiments ===
Although the printers and the like as the first to third embodiments have been described, the above embodiments are for facilitating the understanding of the present invention, and are not intended to limit the present invention. Absent. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

<Light emission time in UV lamp>
In each of the above-described embodiments, the process is executed on the assumption that the UV light emission time in the UV lamp 61 is a fixed value. However, in addition to controlling the ultraviolet irradiation position 13 to change according to each mode and making the curing start time of ultraviolet rays in the ink 10 equal between the modes, the time during which the ink 10 is exposed to ultraviolet rays, that is, the exposure time is also between modes. It is more preferable that the control is performed so as to be equal to each other.

  For example, when the ratio of the size of the conveyance speed of the sheet 5 in the low-speed conveyance mode, that is, the first mode, and the conveyance speed of the sheet 5 in the high-speed conveyance mode, that is, the second mode is 1: 2. In accordance with the inverse ratio, the controller 100 sets the light emission time of the UV lamp 61 to “1” when executing the high-speed transfer mode, and sets the light emission time of the UV lamp 61 when executing the high-speed transfer mode when executing the low-speed transfer mode. “2” which is twice as large as

  Thus, by performing control so that the exposure time of ultraviolet rays becomes equal between the modes as well as the curing start time by ultraviolet rays, even in a situation where the above-described first and second operation modes are switched, The image quality of the image formed on the sheet 5 becomes the same quality at a higher level between the operation modes.

DESCRIPTION OF SYMBOLS 1 Printer, 13 Ultraviolet irradiation position 20 Feeding shaft, 21 Drive roller 25 Winding shaft, 30 Platen drum 31 Front drive roller, 32 Rear drive roller 33, 34 Drive roller, 40 Conveyance unit 40
47 driven roller, 50 head unit 51, 52 head, 60 irradiation unit 61-63 UV lamp (ultraviolet light source), 64 first irradiation unit 65 second irradiation unit, 70 detector group 71 drum encoder, 72-74 tension sensor 75 Edge sensor, 80 Rotating unit 80 Casa member (irradiation position changing member), 84 Pin fulcrum 81 Rotating motor, 90 Light source moving means 92 Pinion, 91 Light source moving motor 93 Rack, 100 Controller 101 Memory, 102 Program 103 CPU, 104 Interface unit 105 Unit control circuit, 106 Internal bus 107 External bus, 110 Speed control unit 111 Irradiation position control unit, 200 Computer

Claims (8)

A printing apparatus that forms an image by ejecting ultraviolet curable ink onto a medium being conveyed through a conveyance path and irradiating the ink landed on the medium with ultraviolet light from an ultraviolet light source.
A speed control unit that switches the medium conveyance speed between a first mode in which the medium conveyance speed is a predetermined speed and a second mode in which the medium conveyance speed is higher than the predetermined speed;
An irradiation position changing member for changing an ultraviolet irradiation position on the medium by the ultraviolet light source;
By controlling the irradiation position changing member, the ultraviolet irradiation position is shifted downstream from the predetermined position on the medium in the first mode in the first mode, and from the predetermined position on the medium in the second mode. An irradiation position control unit for shifting the ultraviolet irradiation position to the upstream side of the conveyance path;
A printing apparatus comprising: The printing apparatus according to claim 1,
The irradiation position changing member includes a pivotable member that fixes a fulcrum at a predetermined position of the printing apparatus and determines an irradiation direction of the ultraviolet light source, and the irradiation position control unit is configured to change the irradiation position. The transition of the ultraviolet irradiation position according to each mode is performed by controlling the rotation of the bulk member in the member.
A printing apparatus characterized by that. A printing apparatus that forms an image by ejecting ultraviolet curable ink onto a medium being conveyed through a conveyance path and irradiating the ink landed on the medium with ultraviolet light from an ultraviolet light source.
The ultraviolet light source includes a first irradiating unit that irradiates ultraviolet rays upstream from a predetermined position in the transport path, and a second irradiating unit that performs ultraviolet irradiation downstream from a predetermined position in the transport path. Yes,
A speed control unit that switches the medium conveyance speed between a first mode in which the medium conveyance speed is a predetermined speed and a second mode in which the medium conveyance speed is higher than the predetermined speed;
An irradiation position control unit that drives the first irradiation unit in the first mode and drives the second irradiation unit in the second mode to perform switching control of each irradiation unit;
A printing apparatus characterized by that. A printing apparatus that forms an image by ejecting ultraviolet curable ink onto a medium being conveyed through a conveyance path and irradiating the ink landed on the medium with ultraviolet light from an ultraviolet light source.
A speed control unit that switches the medium conveyance speed between a first mode in which the medium conveyance speed is a predetermined speed and a second mode in which the medium conveyance speed is higher than the predetermined speed;
Light source moving means for moving the ultraviolet light source on the transport path;
By controlling the light source moving means, the ultraviolet light source is moved downstream from the predetermined position on the medium when the medium is transported at a low speed, and the transport path is transported from the predetermined position on the medium when the medium is transported at a high speed. An irradiation position control unit for moving the ultraviolet light source upstream;
A printing apparatus comprising: The printing apparatus according to any one of claims 1 to 4,
The irradiation position control unit has a time between the first mode and the second mode from when the ink lands on the medium to when the irradiation with the ultraviolet light source is started. The control is executed as much as possible.
A printing apparatus characterized by that. A printing apparatus that forms an image by ejecting ultraviolet curable ink onto a medium that is being conveyed through a conveyance path, and irradiating the ink landed on the medium with ultraviolet light from an ultraviolet light source.
A speed control process for switching the medium conveyance speed between a first mode in which the medium conveyance speed is a predetermined speed and a second mode in which the medium conveyance speed is higher than the predetermined speed;
By controlling the irradiation position changing member that changes the ultraviolet irradiation position on the medium by the ultraviolet light source, the ultraviolet irradiation position is shifted from the predetermined position on the medium to the downstream side of the conveyance path in the first mode. , An irradiation position control process for shifting the ultraviolet irradiation position to the upstream side of the conveyance path from a predetermined position on the medium in the second mode;
The printing method characterized by performing. In a printing apparatus that forms an image by ejecting ultraviolet curable ink onto a medium being conveyed through a conveyance path, and irradiating the ink landed on the medium with ultraviolet light from an ultraviolet light source.
The ultraviolet light source includes a first irradiating unit that irradiates ultraviolet rays upstream from a predetermined position in the transport path, and a second irradiating unit that performs ultraviolet irradiation downstream from a predetermined position in the transport path. Yes,
A speed control process for switching the medium conveyance speed between a first mode in which the medium conveyance speed is a predetermined speed and a second mode in which the medium conveyance speed is higher than the predetermined speed;
An irradiation position control process for driving the first irradiation unit in the first mode, and driving the second irradiation unit in the second mode to perform switching control of each irradiation unit;
The printing method characterized by performing. A printing apparatus that forms an image by ejecting ultraviolet curable ink onto a medium that is being conveyed through a conveyance path, and irradiating the ink landed on the medium with ultraviolet light from an ultraviolet light source.
A speed control process for switching the medium conveyance speed between a first mode in which the medium conveyance speed is a predetermined speed and a second mode in which the medium conveyance speed is higher than the predetermined speed;
By controlling light source moving means for moving the ultraviolet light source on the transport path, the ultraviolet light source is moved downstream from the predetermined position on the medium when transporting the medium at a low speed, and the medium is transported at high speed. Sometimes the irradiation position control process for moving the ultraviolet light source from the predetermined position on the medium to the upstream side of the conveyance path,
The printing method characterized by performing.

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