JP2010131786A - Fluid jetting apparatus and conveyance method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase variation for an image quality of an image reproducible by a fluid jetting apparatus. <P>SOLUTION: The fluid jetting apparatus includes a first head and a second head which are opposed to a medium and jet fluids of different colors from each other to the medium, a conveyance mechanism which moves a region on the medium located on a first opposite position opposed to the first head to a second opposite position opposed to the second head by conveying the medium, and a change mechanism for changing a movement distance of the region from the first opposite position to the second opposite position. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fluid ejecting apparatus and a conveying method.

As a fluid ejecting apparatus, an ink jet printer or the like that prints an image by ejecting a fluid (for example, ink) onto a medium such as paper or film is known. In such a printer, a first head and a second head that eject inks of different colors that face the medium, and a first facing position that the first head faces by conveying the medium And a transport mechanism that moves the region on the medium located at a second facing position where the second head faces (see, for example, Patent Document 1).
JP 2007-210244 A

Nowadays, there is a demand for a printer capable of printing images with various image quality. More specifically, it is desired that variations be increased with respect to image quality such as color, texture, and glossiness reproduced by a printer. Further, the image quality is affected by the state of the ink after the ink has landed on the medium (specifically, the degree of ink bleeding or the degree of curing if the ink is cured by receiving ultraviolet rays). Therefore, if the state of the ink after landing on the medium can be artificially controlled, variations in image quality can be increased.
Further, regarding the state of the ink after landing on the medium, the time (hereinafter also referred to as a printing interval) from when the ink has landed on the medium until another ink (for example, ink of another color) has landed. It can be controlled by adjusting.

  The present invention has been made in view of the above contents, and an object thereof is to increase variations in the image quality of an image that can be reproduced by the fluid ejecting apparatus.

In order to solve the above problems, the main invention is:
A first head and a second head that are opposed to the medium and eject fluids of different colors onto the medium;
A transport mechanism for transporting the medium to move a region on the medium located at a first facing position where the first head is opposed to a second facing position where the second head is opposed;
And a changing mechanism for changing a moving distance of the region from the first facing position to the second facing position.
Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

  At least the following will be made clear by the description of the present specification and the accompanying drawings.

The fluid ejecting apparatus according to the present invention first includes
A first head and a second head that are opposed to the medium and eject fluids of different colors onto the medium;
A transport mechanism for transporting the medium to move a region on the medium located at a first facing position where the first head is opposed to a second facing position where the second head is opposed;
A change mechanism for changing a moving distance of the region from the first facing position to the second facing position. In such a fluid ejecting apparatus, by changing the moving distance, the time from when the first head ejects fluid until the second head ejects fluid, that is, the above-described printing interval can be adjusted. It becomes possible. As a result, variations in image quality that can be reproduced by the fluid ejecting apparatus increase.

In the above fluid ejecting apparatus,
The fluid ejected by each of the first head and the second head is an ultraviolet curable ink that is cured by receiving ultraviolet rays,
An irradiation device for irradiating ultraviolet rays to the ultraviolet curable ink landed on the region;
The light receiving position where the region receives the ultraviolet rays from the irradiation device is a movement path when the region moves from the first facing position to the second facing position, and the first facing position and the second facing position are Located between
The changing mechanism may change a time until the region is positioned from the light receiving position to the second facing position by changing the moving distance. With such a fluid ejecting apparatus, it is possible to adjust the degree of curing of the ultraviolet curable ink ejected by the first head, thereby increasing variations in image quality.

In the above fluid ejecting apparatus,
A third head having a nozzle and ejecting ultraviolet curable ink having a different color from the first head and the second head to the medium from the nozzle;
A third head position at which the third head faces the third head when the ultraviolet curable ink is jetted is located between the first head position and the second head position in the movement path;
A cap that covers the nozzle when the third head does not eject ultraviolet curable ink,
When the third head ejects ultraviolet ink, the changing mechanism sets the movement path as a first movement path that does not allow the third head to face the medium and the cap, and the third head has ultraviolet light. When the curable ink is not ejected, the movement path may be a second movement path in which the third head faces the cap without facing the medium. In such a fluid ejecting apparatus, the changing mechanism has a function of changing the moving distance and a function of switching an object to be opposed (that is, a medium and a cap) opposed to the third head.

In the above fluid ejecting apparatus,
Irradiating ultraviolet rays to the ultraviolet curable ink landed on the region, and having another irradiation device different from the irradiation device,
When the changing mechanism sets the moving path as the first moving path, after the irradiation apparatus irradiates the ultraviolet curable ink from the first head that has landed on the region, the other irradiation apparatus Irradiating the ultraviolet curable ink from the third head landed on the region with ultraviolet rays;
When the changing mechanism sets the movement path as the second movement path, after the irradiation apparatus irradiates the ultraviolet curable ink from the first head that has landed on the region, the other irradiation apparatus further includes The ultraviolet curable ink from the first head that has landed on the region may be irradiated with ultraviolet rays. With such a fluid ejecting apparatus, even when the third head does not eject the ultraviolet curable ink, other irradiation apparatuses can be used effectively.

In the above fluid ejecting apparatus,
The medium is a belt-like continuous medium,
The transport mechanism is
A delivery roller for delivering the continuous medium and delivering the continuous medium;
A take-up roller that winds the continuous medium fed by the feed roller;
A plurality of tension rollers that are positioned between the feed roller and the take-up roller and rotate while the continuous medium is hung on an outer peripheral surface, and convey the continuous medium while being stretched;
The plurality of tension rollers are
The position where the continuous medium is hung on the outer peripheral surface is located between the first facing position and the second facing position in the moving path, and is supported so as to be movable in a direction crossing the axis when rotating. Moving rollers,
The changing mechanism may change the moving distance by moving the moving roller in a direction intersecting the axis. With such a fluid ejecting apparatus, it is possible to reliably change the moving distance when the medium is a continuous medium.

In the above fluid ejecting apparatus,
The fluid ejecting apparatus is a printing apparatus that prints an image on the continuous medium,
While the printing apparatus interrupts the image printing process, the changing mechanism changes the moving distance by moving the moving roller in a direction intersecting the axis,
When the change mechanism is changed so as to shorten the moving distance, the feeding roller is rewound the continuous medium by the moving distance is shortened with the winding roller stopped.
The printing apparatus may resume the printing process after the feeding roller rewinds the continuous medium by the amount of movement distance. When the moving distance is shortened, the continuous medium is slackened. However, the fluid ejecting apparatus described above can eliminate the slack without discharging the continuous medium wastefully.

Alternatively, in the above fluid ejecting apparatus,
The fluid ejecting apparatus is a printing apparatus that prints an image on the continuous medium,
While the printing apparatus interrupts the image printing process, the change mechanism changes the moving distance by moving the moving roller in a direction intersecting the axis,
When the change mechanism is changed so as to shorten the moving distance, the take-up roller takes up the continuous medium by the amount that the moving distance is shortened in a state where the feeding roller is stopped,
While the take-up roller is taking up the continuous medium as the moving distance is shortened, the printing apparatus is in a state where the feed roller is stopped and the second head is in the second facing position. The printing process may be resumed by ejecting ultraviolet curable ink onto the region located. The above configuration is another configuration for eliminating the slack, and the time loss is shortened as compared with the above-described configuration (a configuration in which the feeding roller rewinds the continuous medium to eliminate the slack). It becomes possible.

Furthermore, according to the present invention,
By transporting the medium, a second facing position where the second head that ejects a fluid having a color different from that of the first head is opposed to the area on the medium that is located at the first facing position where the first head faces. A transport method to move to
Changing the moving distance of the region from the first facing position to the second facing position;
It is also possible to realize a transfer method including moving the region located at the first facing position by the changed moving distance and placing it at the second facing position. If the medium is transported by the above transport method when an image is formed on the medium, variations in image quality of the image can be increased.

=== About the fluid ejection device of the present embodiment ===
In this embodiment, an ink jet printer (hereinafter, printer 10) as an example of a fluid ejecting apparatus will be described. The printer 10 of the present embodiment is a printing apparatus that prints an image on a continuous medium S by ejecting ink as an example of a fluid onto a continuous medium S (for example, web-like paper or film) that is continuous in a belt shape. It is. The portion of the continuous medium S on which the image is printed is later cut out and used as a printed material. The continuous medium S is set in the printer 10 while being wound in a roll shape, and is fed out when an image is printed.

  The ink used in the printer 10 of the present embodiment is an ultraviolet curable ink (hereinafter, UV ink) that is cured by receiving ultraviolet rays. A UV ink is an ink prepared by adding an auxiliary agent such as an antifoaming agent to a mixture of a vehicle, a photopolymerization initiator, and a pigment containing an ultraviolet curable resin. Curing occurs when a photopolymerization reaction occurs. In the present embodiment, four color UV inks of KCMY are used to print a color image.

  Further, in the printer 10 of the present embodiment, white UV ink (hereinafter, white ink) is used in addition to the four color UV inks. This white ink is used to print a white background image (so-called background), for example, when solid color is printed on the transparent film when a color image is printed on the transparent film. That is, a color image can be printed on the background image by overprinting the KCMY color inks on the background image composed of white ink.

  Further, in the printer 10 of the present embodiment, clear ink is further used in addition to the above five color UV inks. The clear ink is a colorless and transparent UV ink. For example, the clear ink can be applied to an image composed of the above-described five colors of inks to increase the glossiness of the image.

<< Basic Configuration of Printer 10 >>
A basic configuration of the printer 10 will be described with reference to FIGS. 1 to 3. FIG. 1 is a block diagram showing the overall configuration of the printer 10. FIG. 2 is a schematic diagram illustrating the internal configuration of the printer 10. FIG. 3 is a diagram showing an array of nozzle rows formed in each line head 21.

  As shown in FIG. 1, the printer 10 includes a head unit 20, a transport unit 30 as a transport mechanism, a UV irradiation unit 40, a maintenance unit 50, and a change unit 60 as a change mechanism. Further, the printer 10 includes a controller 70 that controls each unit described above, and a detector group 80.

  The head unit 20 ejects each UV ink on the continuous medium S in order to print an image on the continuous medium S. As shown in FIG. 2, the head unit 20 according to the present embodiment includes a plurality (specifically six) of line heads 21 provided for each ink. As shown in the figure, the plurality of line heads 21 are fixed at substantially the same position in the vertical direction and are arranged at regular intervals in the horizontal direction. Each line head 21 is opposed to the continuous medium S on its lower surface, and ejects UV ink onto the continuous medium S from the nozzles Nz formed on the lower surface.

  In the present embodiment, the white line head 21W that ejects white ink from the side (upstream side) to which the continuous medium S is supplied (upstream side) to the side (downstream side) and the black (K) UV ink are ejected. Black line head 21K for ejecting, cyan line head 21C for ejecting cyan (C) UV ink, magenta line head 21M for ejecting magenta (M) UV ink, yellow line head for ejecting yellow (Y) UV ink 21Y and the clear ink line head 21H that ejects clear ink are arranged in this order. However, the positional relationship between the line heads 21 is not limited to the above-described positional relationship. Further, the white line head 21W and the clear ink line head 21H may not be provided.

  The line heads 21 will be described in detail. Each of the line heads 21 is a long head having a width somewhat longer than the width of the continuous medium S (the length in the direction passing through the paper surface in FIG. 2). Further, as shown in FIG. 3, a plurality of nozzles Nz arranged in a line along the longitudinal direction of each line head 21 is formed on the lower surface of each line head 21. Each nozzle Nz is provided with an ink chamber and a piezoelectric element (not shown). When the piezo element is driven and the ink chamber is contracted and expanded, UV ink is ejected in droplets from each nozzle. When the ejected droplet-shaped UV ink lands on the continuous medium S, dots are formed. As described above, when the area on the continuous medium S passes immediately below each line head 21 (that is, the position where each line head 21 faces the area), the UV ink is discharged from the plurality of nozzles Nz of each line head 21. The dots are ejected and dots corresponding to the width of the continuous medium S are formed in the region at a time.

  The transport unit 30 transports the continuous medium S to move an area on the continuous medium S along a predetermined movement path. The transport unit 30 includes a paper feed roller 31 as a feed roller, a paper discharge roller 32 as a take-up roller, a tension roller 33, and a platen 34 (see FIG. 1).

  As shown in FIG. 2, the paper feed roller 31 is a roller located on the most upstream side in the movement path, and is a roller that feeds out the continuous medium S by feeding out the continuous medium S wound in a roll shape. As shown in FIG. 2, the paper discharge roller 32 is a roller located on the most downstream side in the movement path, and is a roller that winds the continuous medium S sent out by the paper supply roller 31.

  The tension roller 33 is a roller positioned between the paper feed roller 31 and the paper discharge roller 32, and a plurality of tension rollers 33 are provided as shown in FIG. Each tension roller 33 is supported so as to be rotatable about a rotation axis whose axial direction is along the width direction of the continuous medium S. Each tension roller 33 rotates while the continuous medium S is hung on the outer peripheral surface, thereby conveying the continuous medium S while stretching. Each tension roller 33 has a function of changing the conveying direction of the continuous medium S. The platen 34 supports the continuous medium S under the line head 21, and a plurality of platens 34 are provided for each line head 21 as shown in FIG.

  The transport unit 30 configured as described above is configured so that each component of the transport unit 30 (that is, the paper feed roller 31, the paper discharge roller 32, the tension roller 33, and the platen 34) cooperates to form a continuous medium. S is conveyed and the area on the continuous medium S is moved to the downstream side of the movement path. That is, the transport unit 30 performs a transport operation so that the region located on the continuous medium S at a position where one line head 21 of the plurality of line heads 21 is opposed to the one line head 21. The downstream line head 21 is moved to a facing position.

  Note that the platen 34 according to the present embodiment is extendable in the longitudinal direction. In the extended platen 34, one end portion in the longitudinal direction (the end portion on the paper discharge roller 32 side) is located downstream of the line head 21 in the transport direction. As a result, as shown in FIG. 4A, when the platen 34 is in the extended state, the line head 21 positioned immediately above the platen 34 faces the continuous medium S supported by the platen 34. FIG. 4A is a diagram illustrating a state around the platen 34 in the extended state. On the other hand, in the platen 34 in the contracted state, the one end in the longitudinal direction is located upstream of the line head 21 in the transport direction. As a result, as shown in FIG. 4B, when the platen 34 is in the contracted state, the line head 21 located at a position immediately above the platen 34 does not face the continuous medium S (in other words, on the continuous medium S). (The region of (2) does not pass through the position where the line head 21 faces). FIG. 4B is a diagram illustrating a state around the platen 34 in the contracted state.

  Then, the platen 34 positioned under the line head 21 in the state of ejecting UV ink in the plurality of line heads 21 (that is, the print execution state) is in an extended state, and does not eject UV ink (ie, The platen 34 located under the line head 21 in the printing standby state) is in a contracted state.

  In the present embodiment, the plurality of tension rollers 33 are arranged with a certain regularity. Specifically, as shown in FIG. 2, among the plurality of tension rollers 33, the tension rollers excluding the two tension rollers 33 located on the most upstream side and the three tension rollers 33 located on the most downstream side. 33 is regularly arranged every four.

  More specifically, a tension roller 33 (hereinafter referred to as a first tension roller 33a) located on the side of the other longitudinal end of each platen 34 (the end on the paper feed roller 31 side) and one longitudinal end of each platen 34 are described. A tension roller 33 (hereinafter referred to as a second tension roller 33b) that changes the conveying direction so as to fold back the continuous medium S and a downstream side of the second tension roller 33b. A tension roller 33 (hereinafter referred to as a third tension roller 33c) that changes the conveyance direction so as to convey it obliquely below, and is located somewhat below the third tension roller 33c, and changes the conveyance direction into a substantially V-shape. A tension roller 33 (hereinafter referred to as a fourth tension roller 33d) is arranged in a group. A combination of the four tension rollers 33 (that is, the first tension roller 33a to the fourth tension roller 33d) is provided by the number of line heads 21 along the movement path.

  The UV irradiation unit 40 faces the continuous medium S in order to fix the dots on the continuous medium S after the UV ink ejected by each line head 21 has landed on the continuous medium S to form dots. (That is, UV ink landed on the continuous medium S) is irradiated with ultraviolet rays. The UV irradiation unit 40 includes a UV irradiation mechanism 41 as shown in FIG. In the present embodiment, a plurality of UV irradiation mechanisms 41 are provided for each line head 21. More specifically, a UV irradiation mechanism 41 is arranged on the downstream side of each line head 21 in the movement path. Each UV irradiation mechanism 41 includes the preliminary irradiation device 41a and the main irradiation device 41b illustrated in FIG.

  The pre-irradiation device 41a is opposed to the continuous medium S behind the line head 21, and irradiates the UV ink ejected by the line head 21 with ultraviolet rays. As shown in FIG. 2, the preliminary irradiation device 41 a is located above the platen 34 (specifically, one end in the longitudinal direction of the platen 34), and the line head 21 (specifically, the corresponding line head 21. ). The irradiation intensity when the pre-irradiation device 41a irradiates ultraviolet rays is set so weak that the UV ink that has received the ultraviolet rays is cured in the vicinity of its surface (that is, the UV ink is in a semi-cured state). . Further, when the platen 34 is in the contracted state, the preliminary irradiation device 41a located at a position immediately above the platen 34 does not face the continuous medium S (see FIG. 4B).

  The main irradiation device 41b is disposed on the downstream side of the preliminary irradiation device 41a in the moving path, and further irradiates the UV ink that has received the ultraviolet light from the preliminary irradiation device 41a with ultraviolet rays. As shown in FIG. 2, the main irradiation device 41b is located below the platen 34 and faces the continuous medium S between the second tension roller 33b and the third tension roller 33c. The irradiation intensity when the main irradiation device 41b irradiates ultraviolet rays is stronger than the irradiation intensity when the preliminary irradiation device 41a irradiates ultraviolet rays. The semi-cured UV ink gradually transitions to a completely cured state by receiving the ultraviolet rays irradiated by the irradiation device 41b. Further, the irradiation device 41b always faces the continuous medium S regardless of the expansion / contraction state of the platen 34 (see FIGS. 4A and 4B).

  In the UV irradiation unit 40 having the above configuration, the UV irradiation mechanism 41 corresponding to each line head 21 irradiates the UV ink ejected from each line head 21 with ultraviolet rays. Here, the UV irradiation mechanism 41 corresponding to the line head 21 is the UV irradiation mechanism 41 closest to the line head 21 among the UV irradiation mechanisms 41 arranged on the downstream side of the line head 21 in the movement path. In order to cure the UV ink ejected mainly by the line head 21, ultraviolet rays are irradiated. For example, the UV irradiation mechanism 41 corresponding to the black line head 21K is closest to the black line head 21K among the UV irradiation mechanisms 41 located on the downstream side of the black line head 21K, and mainly uses black (K) UV ink. Irradiate ultraviolet rays to cure.

  As a light source when the UV irradiation mechanism 41 (specifically, the preliminary irradiation device 41a and the main irradiation device 41b) irradiates ultraviolet rays, a UV-LED, a metal halide lamp, a xenon lamp, a carbon arc lamp, a chemical lamp, A low-pressure mercury lamp, a high-pressure mercury lamp, etc. can be used.

  The maintenance unit 50 performs maintenance on each line head 21 so that the ink ejection from the nozzles Nz is well maintained. As shown in FIG. 1, the maintenance unit 50 includes a cap 51 and a suction pump 52.

  The cap 51 is a substantially box-shaped member whose upper end is an open end, and a plurality of caps 51 are provided for each line head 21 as shown in FIG. Each cap 51 abuts the lower surface of the line head 21 at its upper end to cover the nozzle Nz of the line head 21. The cap 51 according to the present embodiment contacts the line head 21 and seals the nozzle Nz of the line head 21. Accordingly, it is possible to suppress the clogging of the nozzle Nz caused by the solvent evaporation of the UV ink in the vicinity of the opening of the nozzle Nz of the line head 21 while the line head 21 is in the print standby state. Become.

  Each cap 51 is located directly below the line head 21 and can be moved in the vertical direction by a drive mechanism (not shown). In addition, each line head 21 faces the cap 51 positioned immediately below each line head 21 when UV ink is not ejected (that is, in a print standby state).

  More specifically, when one line head 21 ejects UV ink, the platen 34 positioned immediately below the one line head 21 is in an extended state, and the cap 51 is positioned below the platen 34. , Apart from the one line head 21 (see FIG. 4A). On the other hand, when one line head 21 does not eject UV ink, the platen 34 located immediately below the one line head 21 is in a contracted state, and the platen 34 that has reached the upper position of the cap 51 until then is One end of the longitudinal direction and the continuous medium S supported by the platen 34 come out of the upper position of the cap 51. As a result, the one line head 21 is opposed to the cap 51 located immediately below. In this state, the cap 51 rises to a position where it comes into contact with the lower surface of the one line head 21 (see FIG. 4B).

  The suction pump 52 is connected to the cap 51 and operates in a state where the cap 51 seals the nozzle Nz. As a result, the inner space of the cap 51 is in a negative pressure state, and the UV ink in the nozzle Nz is sucked and forcibly discharged. As described above, the maintenance unit 50 performs the operation (cleaning operation) of forcibly discharging the ink in the nozzle Nz by driving the suction pump 52 in a state where the nozzle 51 is sealed in the cap 51. By such a cleaning operation, the ink ejection from the nozzle Nz is maintained well.

  The change unit 60 is for changing the distance between prints. The inter-printing distance is a moving distance when the area on the continuous medium S located at the first facing position where the first head faces is moved to the second facing position where the second head faces. In addition, the first head and the second head are heads that eject UV inks having different colors from each other so as to face the continuous medium S, and are two line heads 21 that are different from each other in this embodiment. The first head is one of the plurality of line heads 21, and the second head is UV ink downstream of the line head 21 corresponding to the first head in the movement path of the region. This is a line head 21 for jetting. In the printer 10 of the present embodiment, the controller 70 controls the change unit 60 so that the distance between prints can be adjusted. Details of the change unit 60 will be described later.

  The controller 70 controls each unit of the printer 10 through the unit control circuit 74 by the CPU 72 in accordance with a program stored in the memory 73. The controller 70 can communicate with the host computer 110 via the interface 71. When the print data is received from the host computer 110, the controller 70 controls the units based on the print data to continuously display images corresponding to the print data. Printing on the medium S. The situation in the printer 10 is monitored by a detector group 80, and the detector group 80 outputs a signal corresponding to the detection result to the controller 70.

<< Printing Process by Printer 10 >>
Next, a printing process for printing an image by the printer 10 having the above configuration will be described.
The printing process starts when the controller 70 receives print data sent from the host computer 110 via the interface 71. The controller 70 analyzes the contents of various commands in the received print data and controls each unit of the printer 10. Thereby, the conveyance operation by the conveyance unit 30 is first performed. More specifically, the continuous medium S wound in a roll shape is fed out by the paper feed roller 31 to send out the continuous medium S, and the continuous medium S is conveyed while the plurality of tension rollers 33 rotate, and discharged. A roller 32 winds the continuous medium S.
The controller 70 executes the transport operation by the transport unit 30, while executing the UV ink ejection operation by the head unit 20 and the ultraviolet irradiation operation by the UV irradiation unit 40. As a result, a color image is printed on the continuous medium S.

More specifically, the black line head 21K ejects black (K) UV ink onto an area on the continuous medium S located at a position facing the black line head 21K. Thereby, black (K) dots are formed in the region. As described above, the dots corresponding to the width of the continuous medium S are formed at a time.
Thereafter, when the transport unit 30 transports the continuous medium S, the region moves downstream from the position where the black line head 21K faces. Accordingly, the region reaches a position where the UV irradiation mechanism 41 corresponding to the black line head 21K faces.

  More specifically, the region passes through a position where the preliminary irradiation device 41a of the UV irradiation mechanism 41 facing the black line head 21K is opposed, and then is positioned at a position where the main irradiation device 41b of the UV irradiation mechanism 41 faces. Will come. Then, UV light (black (K) UV ink) that has landed on the region is irradiated with ultraviolet rays at each of the position where the preliminary irradiation device 41a faces and the position where the main irradiation device 41b faces. That is, the UV ink ejected from the black line head 21K receives ultraviolet rays immediately after landing on the area. As a result, the dots formed by the UV ink are fixed on the area.

  Thereafter, the region moves further downstream and eventually comes to a position where the cyan line head 21C faces. Thereafter, the same operation as described above is repeated for each UV ink, and a color image piece (a part of the color image) is formed in the region. As a result, a color image is finally printed on the continuous medium S.

  In the case of forming a background image of a color image, the white line head 21 </ b> W is placed on a portion of the continuous medium S where the color image is formed before the KCMY line heads 21 </ b> K to 21 </ b> Y eject UV ink. Solid white ink is applied, and the UV irradiation mechanism 41 corresponding to the white line head 21W irradiates the white ink with ultraviolet rays. In other words, when the background image is formed, the area on the continuous medium S where the KCMY line heads 21K to 21Y are located at the positions where the white line heads 21W face each other is positioned in advance. It passes through the position where the UV irradiation mechanism 41 corresponding to the line head 21W faces.

  When applying clear ink on an image, after the image is formed on the continuous medium S, the clear ink line head 21H ejects clear ink onto the image, and the UV irradiation mechanism 41 faces the clear ink line head 21H. However, the clear ink is irradiated with ultraviolet rays so as to face the portion on the continuous medium S where the clear ink has landed. In other words, when the clear ink is applied on the image, the area is located at a position where the KCMY line heads 21K to 21Y face each other, and then the position where the clear ink line head 21H faces, and the clear ink line head 21H. And the corresponding UV irradiation mechanism 41 passes through a facing position.

  By the way, when the controller 70 executes the above-described series of operations based on the print data, an image corresponding to the print data is printed on the continuous medium S. Depending on the print data, UV ink that is not used when printing an image may be generated among a plurality of types of UV ink prepared in the printer 10. In other words, there may be a line head 21 that does not eject UV ink (that is, the line head 21 in a print standby state) among the plurality of line heads 21. In such a case, the controller 70 contracts the platen 34 located under the line head 21 in the print standby state. As a result, the line head 21 in the print standby state does not face the continuous medium S as described above, but faces the cap 51 positioned immediately below the line head 21.

  Further, the preliminary irradiation device 41a of the UV irradiation mechanism 41 corresponding to the line head 21 in the print standby state also does not face the continuous medium S. On the other hand, the main irradiation device 41b of the UV irradiation mechanism 41 continues to face the continuous medium S and continues to irradiate the continuous medium S with ultraviolet rays.

  Further, the controller 70 raises the cap 51 positioned immediately below the line head 21 in the print standby state, and causes the cap 51 to seal the nozzles Nz of the line head 21 in the print standby state. Then, the controller 70 performs the cleaning operation on the line head 21 in the print standby state by operating the suction pump 52 in a state where the nozzle 51 is sealed in the cap 51. Thus, when the line head 21 in the print standby state again ejects UV ink, ink ejection from the nozzles Nz of the line head 21 is favorably performed.

=== About Change Unit 60 ===
As described above, the printer 10 of the present embodiment includes the change unit 60 for changing the distance between prints. As described above, the inter-printing distance is the moving distance when the region on the continuous medium S located at the first facing position where the first head is opposed to the second opposing position where the second head is opposed ( That is, the movement distance of the region from the first facing position to the second facing position). Hereinafter, the change unit 60 will be described in detail.

  The change unit 60 according to the present embodiment includes a first drive mechanism 61 and a second drive mechanism 62 as shown in FIG.

  The first drive mechanism 61 moves the fourth tension roller 33d of the plurality of tension rollers 33 in the vertical direction. That is, the fourth tension roller 33d according to the present embodiment is an example of a moving roller that is supported so as to be movable in a direction intersecting with the rotation axis. The first drive mechanism 61 according to the present embodiment includes a guide rail 61a along the vertical direction, and a stepping motor 61b that moves the fourth tension roller 33d along the guide rail 61a (FIGS. 5A and 5B). reference). In the present embodiment, as described above, a plurality (specifically six) of the fourth tension rollers 33d are provided, and a plurality of guide rails 61a and stepping motors 61b are provided for each of the fourth tension rollers 33d. It has been. That is, the first drive mechanism 61 can individually move each fourth tension roller 33d up and down.

  The second drive mechanism 62 moves the second tension roller 33b among the plurality of tension rollers 33 in the horizontal direction (specifically, the direction intersecting the width of the continuous medium S). That is, the second tension roller 33b according to the present embodiment is an example of a moving roller that is supported so as to be movable in a direction intersecting with the rotation axis, like the fourth tension roller 33d. The second drive mechanism 62 according to the present embodiment includes a guide rail 62a along the horizontal direction and a stepping motor 62b that moves the second tension roller 33b along the guide rail 62a (FIGS. 6A and 6B). reference). A plurality (specifically, six) of second tension rollers 33b are also provided, and a plurality of guide rails 62a and stepping motors 62b are provided for each second tension roller 33b. That is, the second drive mechanism 62 can horizontally move each second tension roller 33b individually.

  The change unit 60 having the above configuration moves the fourth tension roller 33d to the first drive mechanism 61, or moves the second tension roller 33b to the second drive mechanism 62, thereby moving the continuous medium S. The distance between the prints is changed by changing the movement path along which the upper region moves. Although the first drive mechanism 61 and the second drive mechanism 62 include the guide rails 61a and 62a and the stepping motors 61b and 62b, respectively, the present invention is not limited to this, and the tension roller that is the drive target As long as 33 (the second tension roller 33b or the fourth tension roller 33d) is moved, another configuration may be used.

  Hereinafter, each operation example of the first drive mechanism 61 and the second drive mechanism 62 will be described. For easy understanding, the operation example of the first drive mechanism 61 will be described assuming that the black line head 21K is the first head and the cyan line head 21C is the second head. An operation example of the second drive mechanism 62 will be described assuming that the black line head 21K is the first head and the magenta line head 21M is the second head.

<< Regarding Operation Example of First Driving Mechanism 61 >>
Under the control of the controller 70, the first drive mechanism 61 moves up and down the fourth tension roller 33d that is positioned downstream of the black line head 21K and upstream of the cyan line head 21C. In the fourth tension roller 33d, the position where the continuous medium S is hung on the outer peripheral surface thereof is the first facing position (that is, the position where the black line head 21K faces) and the second facing position (cyan line) on the moving path. The tension roller 33 is positioned between the head 21C and the opposite position.

  Then, when the first drive mechanism 61 moves the fourth tension roller 33d up and down, the region on the continuous medium S moves from the first facing position to the second facing position as shown in FIGS. 5A and 5B. The movement route when changing is changed. That is, the moving distance of the area from the position where the black line head 21K is opposed to the position where the cyan line head 21C is opposed, that is, the distance between printing is changed. 5A and 5B are diagrams showing how the distance between prints is changed by the operation of the first drive mechanism 61. FIG.

  Note that the amount of movement (indicated by symbol d1 in FIG. 5B) when the first drive mechanism 61 moves the fourth tension roller 33d up and down is determined by the controller 70 according to the print data. Thereby, the distance between printing becomes a distance according to printing data.

  By the way, the region on the continuous medium S is located at a position where the black line head 21K is opposed, and then passes through a position for receiving ultraviolet rays from the UV irradiation mechanism 41 corresponding to the black line head 21K, and then the cyan line head. It reaches the position where 21C faces. That is, the region receives the ultraviolet rays from the preliminary irradiation device 41a of the UV irradiation mechanism 41 corresponding to the first head after leaving the first opposing position and reaching the second opposing position, and The UV irradiation mechanism 41 passes through a position for receiving ultraviolet rays from the main irradiation device 41b.

  Here, the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the first head (that is, the black line head 21K) corresponds to the irradiation unit of the present embodiment. Further, the position where the region receives the ultraviolet rays from the main irradiation device 41b corresponds to the light receiving position of the present embodiment, and the movement when the region on the continuous medium S moves from the first facing position to the second facing position. In the path, it is located between the first facing position and the second facing position.

  Furthermore, in the present embodiment, the fourth tension roller 33d, which is the drive target of the first drive mechanism 61, moves up and down on the downstream side of the light receiving position in the movement path. Therefore, when the first drive mechanism 61 moves the fourth tension roller 33d up and down, the inter-printing distance changes from the light receiving position to the second facing position. For this reason, the time until the area moves from the light receiving position to the second facing position is changed. That is, the change unit 60 moves the fourth tension roller 33d to the first drive mechanism 61 to change the distance between prints until the region on the continuous medium S moves from the light receiving position to the second facing position. Change the time. As a result, it is possible to adjust the degree of curing of the UV ink (that is, black (K) UV ink) from the first head that has landed on the region.

<< Regarding Operation Example of Second Drive Mechanism 62 >>
The second drive mechanism 62 moves the second tension roller 33b horizontally according to whether or not the third head ejects UV ink. Here, the third head is a line head 21 that ejects UV ink having a different color from the nozzle Nz to the first and second heads onto the continuous medium S. And in the movement path | route from the 1st opposing position where a 1st head opposes to the 2nd opposing position where a 2nd head opposes, the 3rd opposing position where a 3rd head opposes is said 1st opposing position and said 2nd Located between the opposite positions. In this specific example (an example in which the black line head 21K is the first head and the magenta line head 21M is the second head), the cyan line head 21C corresponds to the third head.

  Under the control of the controller 70, the second drive mechanism 62 horizontally moves the second tension roller 33b positioned downstream of the black line head 21K and cyan line head 21C and positioned upstream of the magenta line head 21M. . In the second tension roller 33b, the position where the continuous medium S is hung on the outer peripheral surface thereof is the third facing position (that is, the position where the cyan line head 21C faces) and the second facing position (magenta line) in the movement path. The tension roller 33 is positioned between the head 21M and the head 21M.

  Then, when the second drive mechanism 62 moves the second tension roller 33b horizontally, as shown in FIGS. 6A and 6B, the region on the continuous medium S is in the first facing position (the black line head 21K is facing). The movement path when moving from the first facing position to the second facing position is changed, and the moving distance of the area from the first facing position to the second facing position, that is, the distance between prints is changed. 6A and 6B are diagrams showing how the distance between prints is changed by the operation of the second drive mechanism 62. FIG.

  Specifically, when the second drive mechanism 62 horizontally moves the second tension roller 33b, the platen 34 adjacent to the second tension roller 33b expands and contracts. When the cyan line head 21C ejects UV ink, the second drive mechanism 62 positions the second tension roller 33b at the position shown in FIG. 6A. In such a case, the platen 34 adjacent to the second tension roller 33b (that is, the platen 34 positioned below the cyan line head 21C) is in an extended state. Therefore, when the second tension roller 33b is positioned at the position shown in FIG. 6A, the continuous medium S is conveyed so as to pass under the lower surface of the cyan line head 21C. More specifically, one end portion in the longitudinal direction of the platen 34 positioned below the cyan line head 21C reaches between the cyan line head 21C and the cap 51 positioned directly below the cyan line head 21C. As a result, the area on the continuous medium S passes through the third facing position. That is, the cyan line head 21C faces the continuous medium S, but does not face the cap 51.

  On the other hand, when the cyan line head 21C does not eject UV ink, the second drive mechanism 62 positions the second tension roller 33b at the position shown in FIG. 6B. In such a case, the platen 34 adjacent to the second tension roller 33b is in a contracted state. Therefore, when the second tension roller 33b is positioned at the position shown in FIG. 6B, the continuous medium S does not pass under the lower surface of the cyan line head 21C. More specifically, the conveyance direction of the continuous medium S is folded before the cyan line head 21C, and the continuous medium S is retracted from between the cyan line head 21C and the cap 51 positioned immediately below the cyan line head 21C. It becomes like this. That is, the cyan line head 21 </ b> C does not face the continuous medium S, but faces the cap 51. In such a state, the cap 51 moves toward the cyan line head 21C so as to contact the lower surface of the cyan line head 21C.

  As described above, the second drive mechanism 62 horizontally moves the second tension roller 33b, which is the drive target of the second drive mechanism 62, depending on whether the third head ejects UV ink or not. By doing so, the movement path of the area on the continuous medium S from the first facing position to the second facing position is changed. That is, when the third head ejects UV ink, the second drive mechanism 62 sets the moving path as the first moving path that does not allow the third head to face the continuous medium S and the cap 51. On the other hand, when the third head does not eject UV ink, the movement path is set as a second movement path in which the third head is opposed to the continuous medium S and opposed to the cap 51.

  As described above, the second drive mechanism 62 switches the movement path to change the movement distance of the area from the first facing position to the second facing position, that is, the inter-printing distance. That is, the change unit 60 (specifically, the second drive mechanism 62) of the embodiment switches the function of changing the distance between prints and the opposed object (continuous medium S and cap 51) that the third head faces. Combines functionality.

  Similarly to the first drive mechanism 61, the second drive mechanism 62 also changes the inter-printing distance so that the region receives the ultraviolet rays from the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the first head. The time until moving from the (light receiving position) to the second facing position is changed. As a result, it is possible to adjust the degree of curing of the UV ink (that is, black (K) UV ink) from the first head that has landed on the region.

  By the way, when the above movement path becomes the first movement path, the preliminary irradiation apparatus 41a and the main irradiation apparatus 41b of the UV irradiation mechanism 41 corresponding to the third head (cyan line head 21C) are both continuous medium S and Opposite (see FIG. 6A). On the other hand, when the above movement route becomes the second movement route, the preliminary irradiation device 41a of the preliminary irradiation device 41a and the main irradiation device 41b does not face the continuous medium S, whereas the main irradiation device 41b. Still faces the continuous medium S (see FIG. 6B). For this reason, when the above movement path becomes the second movement path (that is, when the third head does not eject UV ink), the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the third head The UV irradiation mechanism 41 corresponding to the head (black line head 21K) and the UV ink from the first head landed on the area on the continuous medium S (that is, the black (K) UV ink) is irradiated with ultraviolet rays. Become.

  More specifically, when the change unit 60 (specifically, the second drive mechanism 62) uses the movement path as the first movement path, the area on the continuous medium S is moved from the first head to the area. After the UV ink has landed, the preliminary irradiation device 41a and the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the first head pass through positions facing each other. Here, the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the first head corresponds to the irradiation device as described above, and the UV ink from the first head landed on the region when facing the region. Irradiate ultraviolet rays. Thereafter, when the area passes through the third facing position, the UV ink from the third head lands on the area. When the region moves further downstream, each of the preliminary irradiation device 41a and the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the third head passes through a facing position. Here, the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the third head corresponds to another irradiation device, and is different from the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the first head. Then, the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the third head irradiates the UV ink from the third head landed on the region when facing the region with ultraviolet rays.

  On the other hand, when the change unit 60 sets the moving path as the second moving path, the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the first head irradiates the UV ink from the first head landed on the region with ultraviolet rays. After that, the region does not face the third head and the preliminary irradiation device 41a of the UV irradiation mechanism 41 corresponding to the third head, but at a position where the main irradiation device 41b of the UV irradiation mechanism 41 faces. To reach. The main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the third head irradiates the UV ink from the first head landed on the region with ultraviolet rays. In this way, when the movement path becomes the second movement path, first, the main irradiation device 41b (irradiation device) of the UV irradiation mechanism 41 corresponding to the first head is landed on the region. The UV ink from is irradiated with ultraviolet rays. Thereafter, the main irradiation device 41b (other irradiation device) of the UV irradiation mechanism 41 corresponding to the third head further irradiates the UV ink from the first head landed on the region with ultraviolet rays.

  As described above, in this embodiment, even when the third head does not eject UV ink, the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the third head can be effectively used.

<< Attachment when the distance between prints is changed >>
The operations of the first drive mechanism 61 and the second drive mechanism 62 described above are performed while the printer 10 is interrupting the image printing process (for example, when the print image is changed, ink ejection from each line head 21 is performed. Executed while suspended). That is, while the printer 10 interrupts the printing process, the first drive mechanism 61 moves the fourth tension roller 33d, or the second drive mechanism 62 moves the second tension roller 33b. Thereby, the change unit 60 changes the distance between printing.

  When the change unit 60 changes the inter-print distance, it is necessary to execute an operation (accompanying operation) associated with the change operation of the inter-print distance by the change unit 60 in order to appropriately transport the continuous medium S thereafter. is there. For this reason, the controller 70 causes the transport unit 30 to execute the following accompanying operation.

  When the change unit 60 moves the fourth tension roller 33d or the second tension roller 33b so as to increase the distance between prints, as an accompanying operation, the paper feed roller 31 causes the continuous medium S to increase the distance between prints. It will be sent out. Then, after the paper feed roller 31 sends out the continuous medium S by an amount corresponding to the increase in the distance between printing, the printer 10 resumes the printing process. Thereby, after changing so that the distance between printing may become long, the continuous medium S comes to be conveyed appropriately, and a printing process comes to be performed appropriately.

  On the other hand, when the change unit 60 changes the distance between prints to be shorter, the continuous medium S that has been stretched until then becomes slack. When the printing process is resumed, it is necessary to eliminate the slack. In the present embodiment, the paper feeding roller 31 rewinds the continuous medium S by the amount of the shorter distance between printings while the paper discharge roller 32 is stopped. . As a result, the slack is eliminated and the continuous medium S returns to the stretched state. Then, after the paper feed roller 31 rewinds the continuous medium S by an amount corresponding to the shortened distance between printing, the printer 10 resumes the printing process. Thereby, the slack is eliminated without wastefully discharging the continuous medium S. As a result, the continuous medium S is appropriately conveyed after changing the distance between prints to be short, and the printing process is appropriately performed.

=== Effectiveness of Printer 10 of this Embodiment ===
The printer 10 of this embodiment includes a change unit 60, and the change unit 60 is opposed to the line head 21 corresponding to the second head from the first facing position where the line head 21 corresponding to the first head is opposed. The moving distance when the area on the continuous medium S moves to the second facing position, that is, the inter-printing distance is changed. In other words, the transport method of the continuous medium S according to the present embodiment is a transport method of moving the region located at the first facing position to the second facing position by transporting the continuous medium S, Changing the inter-printing distance, and moving the region located at the first opposing position by the changed inter-printing distance to be located at the second opposing position. As described above, variations in the image quality of the print image that can be reproduced by the printer 10 increase.

  That is, as already described in the section of the problem to be solved by the invention, the image quality of the image is in the state of the UV ink after being landed on the continuous medium S (specifically, the degree of curing). Affected. For this reason, if the ink state after landing can be artificially controlled, variations in image quality will increase. In addition, regarding the state of the UV ink after the UV ink has landed on the continuous medium S, the time (printing interval) from when the UV ink has landed on the continuous medium S to when another UV ink has landed is adjusted. Can be controlled.

  In the printer 10 of the present embodiment, as described above, the change unit 60 changes the inter-print distance, so that the line head 21 corresponding to the first head ejects UV ink onto the area on the continuous medium S. After that, the printing interval from when the line head 21 corresponding to the second head ejects UV ink to the region is changed. Further, in the present embodiment, the time from when the UV ink from the first head that has landed on the region is irradiated with ultraviolet rays until the second head ejects the UV ink onto the region is changed by changing the printing interval. (Curing time) is changed. That is, in this embodiment, if the inter-print distance is adjusted based on the print data, the curing time can be adjusted according to the print data.

  As a result, it is possible to adjust the degree of curing of the UV ink from the line head 21 corresponding to the first head until the line head 21 corresponding to the second head ejects the UV ink. Hereinafter, for easier understanding, for example, UV ejected from the line head 21 corresponding to the second head on the UV ink ejected from the line head 21 corresponding to the first head (hereinafter referred to as first ink). A case where ink (hereinafter referred to as second ink) is overprinted is assumed. In this case, as shown in FIGS. 7A and 7B, as the curing time becomes longer, the second ink is overprinted on the first ink while the first ink is smoothed (leveled). 7A and 7B are explanatory diagrams of the effect of adjusting the curing time. FIG. 7A shows the state when the curing time is shortened, and FIG. 7B shows the state when the curing time is lengthened. It is shown.

  Then, depending on the progress of smoothing of the first ink, the color reproduced by the combination of the first ink and the second ink overprinted thereon varies. Therefore, by adjusting the inter-print distance by the change unit 60, the print interval (more specifically, the curing time) can be adjusted. As a result, the reproducible color of the image quality of the image printed by the printer 10 can be adjusted. The variation of will increase.

  Further, since the progress of the smoothing of the first ink can be adjusted, the texture of the printed image (specifically, the unevenness of the surface of the image) can be adjusted. In particular, when the first ink is a clear ink, the glossiness imparted to the image by the clear ink can be adjusted.

  Furthermore, the physical properties (for example, ink viscosity) of each UV ink change as the printing environment (the internal temperature of the printer 10 and the room humidity) changes, so that even if an image is printed based on the same print data, The image quality may change slightly. Even in such a case, if the inter-printing distance is adjusted according to the change of the upper printing environment, the image quality of the image printed based on the same print data can be made uniform (stabilized).

=== Regarding Printer 10 According to Modification Example ===
The printer 10 having the above-described configuration is an example of an embodiment of the printer 10 according to the present invention (hereinafter referred to as the present example), and other configurations (hereinafter, modified examples) are also conceivable. Hereinafter, as a configuration of the printer 10 according to the modification, a first modification and a second modification will be described. In the following description, description of the same components as those in this example is omitted.

<< About the first modification >>
In this example, the configuration in which each of the plurality of line heads 21 is completely fixed has been described. Then, the change unit 60 (more specifically, the second drive mechanism 62) moves each second tension roller 33b to change the distance between prints, so that the line heads 21 face each other (continuous object). The medium S or the cap 51) is switched. On the other hand, in the printer 10 according to the first modification, each of the plurality of line heads 21 is moved to switch the opposed object. Hereinafter, the printer 10 according to the first modification will be described with reference to FIG. FIG. 8 is a schematic diagram illustrating an internal configuration of the printer 10 according to the first modification.

  In the printer 10 according to the first modification, as shown in FIG. 8, the plurality of tension rollers 33 are arranged so that the movement path of the area of the continuous medium S has a substantially rectangular wave shape. Specifically, out of the plurality of tension rollers 33, the tension roller 33 excluding the two tension rollers 33 located on the most upstream side and the three tension rollers 33 located on the most downstream side is divided into four. They are lined up regularly. More specifically, a pair of tension rollers 33 (hereinafter referred to as a pair of fifth tension rollers 33e) disposed so as to sandwich each platen 34 on both sides of each platen 34, and a pair of fifth tension rollers 33e. A pair of tension rollers 33 (hereinafter referred to as a pair of sixth tension rollers 33f) that are positioned below and positioned at substantially the same position in the vertical direction are arranged in a pair. A combination of the tension rollers 33 (that is, a pair of fifth tension rollers 33e and a pair of sixth tension rollers 33f) is provided for the number of line heads 21 along the movement path.

  As shown in FIG. 8, a space is formed above each pair of sixth tension rollers 33f, and a cap 51 is inserted into the fifth tension roller 33e (of the pair of fifth tension rollers 33e). Of these, the fifth tension roller 33e) on the downstream side is arranged so as to be aligned with the platen 34. In this space, the main irradiation device 41 b is disposed below the cap 51 so as to face the continuous medium S.

  In the first modification, as described above, each of the plurality of line heads 21 moves horizontally by a drive mechanism (not shown). More specifically, as shown in FIG. 9A, the line head 21 in the state of ejecting UV ink is positioned immediately above the platen 34 corresponding to the line head 21 (hereinafter, this position is referred to as a print position). To position. On the other hand, as shown in FIG. 9B, the line head 21 in the print standby state is located at a position facing the cap 51 (hereinafter referred to as a standby position). That is, each line head 21 according to the first modification moves horizontally between the printing position and the standby position. 9A is a diagram showing the periphery of the line head 21 located at the printing position, and FIG. 9B is a diagram showing the periphery of the line head 21 located at the standby position.

  On the other hand, the change unit 60 according to the first modification includes a drive mechanism (not shown) that moves each pair of sixth tension rollers 33f up and down. That is, when the drive mechanism moves the pair of sixth tension rollers 33f up and down, the change unit 60 changes the distance between prints (see FIG. 8).

  As described above, in the first modified example, the mechanism for changing the distance between prints and the mechanism for switching the opposed object (continuous medium S or cap 51) with which each line head 21 is opposed are provided separately. It has been. That is, unlike the present example, the change unit 60 does not have the function of changing the distance between prints and the function of switching the opposed object. In the first modified example, since each line head 21 is moved horizontally, it is necessary to move each line head 21 with high precision (positioning after movement is performed with high precision) in order to print an image accurately. On the other hand, in this example, since each line head 21 is fixed, there is no problem regarding the movement accuracy. In this respect, the present example is more advantageous than the first modification.

  By the way, in the first modification, each line head 21 is fixed with a preliminary irradiation device 41a (specifically, the preliminary irradiation device 41a of the UV irradiation mechanism 41 corresponding to each line head 21). For this reason, when each line head 21 moves horizontally from the printing position to the standby position, the preliminary irradiation device 41a fixed to each line head 21 also moves horizontally in conjunction with it. When each line head 21 is positioned at the printing position, the preliminary irradiation device 41a fixed to each line head 21 faces the continuous medium S. When each line head 21 is positioned at the standby position, each line The preliminary irradiation device 41 a fixed to the head 21 does not face the continuous medium S. On the other hand, since the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to each line head 21 is fixed at a position below the cap 51, it faces the continuous medium S regardless of the position of each line head 21 ( 9A and 9B).

  As a result, also in the first modification, as in this example, when the line head 21 corresponding to the third head does not eject UV ink, the main irradiation device 41b of the UV irradiation mechanism 41 corresponding to the line head 21 is used. Can be used effectively. That is, when the line head 21 corresponding to the third head does not eject the UV ink, the main irradiation device 41b (irradiation device) of the UV irradiation mechanism 41 corresponding to the first head applies the UV ink from the first head. After irradiating with ultraviolet rays, the main irradiation device 41b (other irradiation device) of the UV irradiation mechanism 41 corresponding to the third head further irradiates the UV ink from the first head with ultraviolet rays.

<< About the second modification >>
In the present example, as an accompanying operation accompanying the operation for changing the inter-print distance, when the change unit 60 changes the inter-print distance so as to shorten the inter-print distance, the paper feed roller 31 is stopped and the paper discharge roller 32 is stopped. However, the case where the continuous medium S is rewound by the amount that the distance between prints is shortened has been described. Accordingly, it is possible to eliminate the slack that occurs in the continuous medium S when the distance between prints is shortened, but other methods for eliminating the slack are also conceivable. In the printer 10 according to the second modification, an accompanying operation different from the above is executed in order to eliminate the slack.

  More specifically, in the second modification, when the change unit 60 changes the distance between prints to be short, the paper discharge roller 32 removes the continuous medium S between the prints while the paper feed roller 31 is stopped. Take up as much distance as possible. Thereby, the said slack is eliminated. In the second modified example, the inter-print distance changing operation is performed while the printing process is interrupted.

  Further, in the second modified example, while the paper discharge roller 32 is winding the continuous medium S by the amount corresponding to the shortened distance between printing, the printer 10 is in a state where the paper supply roller 31 is stopped. The second head ejects the UV ink onto the area on the continuous medium S located at the opposite position, thereby restarting the printing process. That is, the paper discharge roller 32 winds the continuous medium S by the amount corresponding to the shortened distance between prints, so that one region on the continuous medium S is positioned at the second facing position. At this time, since the UV ink from the line head 21 corresponding to the second head has not landed in the one area, the printing process is started from the point where the line head 21 ejects the UV ink to the one area. Can be resumed.

  As a result of the above, in the second modified example, when the inter-printing distance is changed to be short, the slack that has occurred in the continuous medium S is eliminated, and the time from when the inter-printing distance is changed until the printing process is restarted. Can be shortened. On the other hand, in this example, since the paper feeding roller 31 rewinds the continuous medium S, it takes extra time from changing the inter-printing distance to restarting the printing process. Therefore, the second modified example is more preferable than the present example in that the time loss is shortened. On the other hand, in this example, it is possible to eliminate slack with a simpler procedure than in the second modified example. Therefore, this example is also used for control until the printing process is restarted after changing the inter-printing distance. It becomes simpler than the two variants. In this respect, this example is preferable.

=== Other Embodiments ===
The fluid ejecting apparatus and the transport method according to the present invention have been described above based on the above embodiment. However, the above-described embodiment is for facilitating the understanding of the present invention. It is not intended to limit. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof.

  In the above embodiment, the ink ejected from each of the first head and the second head is a UV ink that is cured by receiving an ultraviolet ray. However, the present invention is not limited to this. For example, general water-based ink and oil-based ink (that is, non-UV curable ink) may be used. Even when the first head and the second head eject general water-based ink and oil-based ink, it is possible to increase variations in image quality by changing the distance between prints. More specifically, when the ink is ejected from the first head and landed on the medium, the ink spreads on the medium. The degree of ink bleeding affects the colors that can be reproduced by the printer 10 and can be adjusted by adjusting the printing interval. Therefore, if the inter-printing distance is changed to adjust the printing interval, the degree of ink bleeding is adjusted. As a result, variations in colors that can be reproduced by the printer 10 can be increased.

  In the above embodiment, the inter-printing distance is changed by moving the second tension roller 33b or the fourth tension roller 33d in a direction intersecting the rotation axis. Thus, when the continuous medium S is used as the image printing medium, the inter-printing distance can be reliably changed. However, the present invention is not limited to this. For example, the tension roller 33 is a pressing member that contacts the continuous medium S and presses the continuous medium S in a direction intersecting the continuous medium S (specifically, the vertical direction). The inter-printing distance may be changed by moving the pressing member in a direction intersecting the continuous medium S.

  In the above embodiment, while the printing process is interrupted, the changing unit 60 performs the operation for changing the inter-printing distance. However, the present invention is not limited to this. The changing operation may be performed.

  In the above-described embodiment, the printer 10 that uses the continuous medium S as a medium for printing an image has been described. However, the present invention is not limited to this, and the medium may be a medium used for image printing, such as a cut sheet (cut sheet paper). In the case of the printer 10 that prints an image using a cut sheet as a medium, a configuration in which the cut sheet is conveyed by a conveyance belt 35 as illustrated in FIG. In this configuration, as shown in FIG. 10, the distance between prints is changed by moving the driving roller 35 a that drives the conveyor belt 35 while stretching the conveyor belt 35 to change the trajectory of the conveyor belt 35. Is possible. FIG. 10 is a diagram illustrating a configuration example of the printer 10 that prints an image using a cut sheet as a medium.

  In the above embodiment, the printer 10 having the line head 21 capable of forming dots corresponding to the width of the medium (specifically, the continuous medium S) at a time has been described. However, the present invention is not limited to this, and a printer 10 (so-called serial printer) having a head that forms a dot row (raster line) along the width by ejecting ink while moving along the width of the medium. There may be. The present invention can also be embodied in such a printer 10 (serial printer).

  In the above embodiment, the printer 10 that ejects ink (more specifically, UV ink) as an example of the fluid ejecting apparatus to print an image has been described. However, the present invention is not limited to this, and liquids other than ink (including liquids in which functional material particles are dispersed and liquids such as gels) and fluids other than liquids (in addition to liquids) The present invention can be embodied in a fluid ejecting apparatus that ejects or discharges a solid that can be ejected by flowing as a fluid. For example, a fluid ejecting apparatus that ejects a liquid containing a material such as an electrode material or a color material used for manufacturing a liquid crystal display, an EL (electroluminescence) display, and a surface emitting display in a dispersed or dissolved state, and a biochip. It may be a fluid ejecting apparatus that ejects bioorganic matter to be used, or a fluid ejecting apparatus that ejects a liquid that is used as a precision pipette and serves as a sample. In addition, transparent resin liquids such as UV curable resins to form fluid injection devices that inject lubricating oil onto precision machines such as watches and cameras, micro hemispherical lenses (optical lenses) used in optical communication elements, etc. A fluid ejecting apparatus that ejects a liquid onto a substrate, a liquid ejecting apparatus that ejects an etching solution such as acid or alkali to etch the substrate, a fluid ejecting apparatus that ejects a gel, a solid such as a powder such as toner A fluid ejecting apparatus that ejects may be used. The present invention can be applied to any one of these fluid ejecting apparatuses.

1 is a block diagram illustrating an overall configuration of a printer. 2 is a schematic diagram illustrating an internal configuration of a printer. FIG. FIG. 3 is a diagram showing an array of nozzle rows formed in each line head 21. FIG. 4A is a diagram illustrating a state around the platen 34 in the extended state. FIG. 4B is a diagram illustrating a state around the platen 34 in the contracted state. 5A and 5B are diagrams showing how the distance between prints is changed by the operation of the first drive mechanism 61. FIG. 6A and 6B are diagrams showing how the distance between prints is changed by the operation of the second drive mechanism 62. FIG. FIG. 7A and FIG. 7B are explanatory diagrams about the effect of adjusting the curing time. It is a schematic diagram which shows the internal structure of the printer 10 which concerns on a 1st modification. FIG. 9A is a diagram showing the periphery of the line head 21 located at the printing position. FIG. 9B is a diagram showing the periphery of the line head 21 located at the standby position. 1 is a diagram illustrating a configuration example of a printer 10 that prints an image using a cut sheet as a medium. FIG.

Explanation of symbols

10 printer, 20 head unit, 21 line head,
21W white line head, 21K black line head,
21C cyan line head, 21M magenta line head,
21Y yellow line head, 21H clear ink line head,
30 transport unit, 31 paper feed roller, 32 paper discharge roller,
33 tension roller, 33a first tension roller,
33b Second tension roller, 33c Third tension roller,
33d fourth tension roller, 33e fifth tension roller,
33f sixth tension roller, 34 platen, 35 transport belt,
35a Drive roller, 40 UV irradiation unit,
41 UV irradiation mechanism, 41a preliminary irradiation apparatus, 41b main irradiation apparatus,
50 maintenance unit, 51 cap, 52 suction pump,
60 change unit, 61 first drive mechanism, 61a guide rail,
61b stepping motor, 62 second drive mechanism, 62a guide rail,
62b stepping motor, 70 controller,
71 interface (I / F), 72 CPU, 73 memory,
74 unit control circuit, 80 detector group, 110 host computer,
Nz nozzle, S continuous medium

Claims (8)

A first head and a second head that are opposed to the medium and eject fluids of different colors onto the medium;
A transport mechanism for transporting the medium to move a region on the medium located at a first facing position where the first head is opposed to a second facing position where the second head is opposed;
A change mechanism for changing a moving distance of the region from the first facing position to the second facing position;
A fluid ejecting apparatus comprising: The fluid ejection device according to claim 1,
The fluid ejected by each of the first head and the second head is an ultraviolet curable ink that is cured by receiving ultraviolet rays,
An irradiation device for irradiating ultraviolet rays to the ultraviolet curable ink landed on the region;
The light receiving position where the region receives the ultraviolet rays from the irradiation device is a movement path when the region moves from the first facing position to the second facing position, and the first facing position and the second facing position are Located between
The fluid ejecting apparatus according to claim 1, wherein the changing mechanism changes a time until the region is positioned from the light receiving position to the second facing position by changing the moving distance. The fluid ejection device according to claim 2,
A third head having a nozzle and ejecting ultraviolet curable ink having a different color from the first head and the second head to the medium from the nozzle;
A third head position at which the third head faces the third head when the ultraviolet curable ink is jetted is located between the first head position and the second head position in the movement path;
A cap that covers the nozzle when the third head does not eject ultraviolet curable ink,
When the third head ejects ultraviolet ink, the changing mechanism sets the movement path as a first movement path that does not allow the third head to face the medium and the cap, and the third head has ultraviolet light. The fluid ejecting apparatus according to claim 1, wherein when the curable ink is not ejected, the moving path is a second moving path that causes the third head to face the cap without facing the medium. The fluid ejection device according to claim 3, wherein
Irradiating ultraviolet rays to the ultraviolet curable ink landed on the region, and having another irradiation device different from the irradiation device,
When the changing mechanism sets the moving route as the first moving route,
After the irradiation device irradiates the ultraviolet curable ink from the first head that has landed on the region, the other irradiation device applies ultraviolet light to the ultraviolet curable ink from the third head that has landed on the region. Irradiated,
When the change mechanism sets the movement route as the second movement route,
After the irradiation device irradiates the ultraviolet curable ink from the first head landed on the region with ultraviolet rays, the other irradiation device further applies ultraviolet rays to the ultraviolet curable ink from the first head landed on the region. The fluid ejecting apparatus characterized by irradiating. The fluid ejection device according to any one of claims 2 to 4,
The medium is a belt-like continuous medium,
The transport mechanism is
A delivery roller for delivering the continuous medium and delivering the continuous medium;
A take-up roller that winds the continuous medium fed by the feed roller;
A plurality of tension rollers that are positioned between the feed roller and the take-up roller and rotate while the continuous medium is hung on an outer peripheral surface, and convey the continuous medium while being stretched;
The plurality of tension rollers are
The position where the continuous medium is hung on the outer peripheral surface is located between the first facing position and the second facing position in the moving path, and is supported so as to be movable in a direction crossing the axis when rotating. Moving rollers,
The change mechanism is configured to change the moving distance by moving the moving roller in a direction intersecting the axis. The fluid ejection device according to claim 5, wherein
The fluid ejecting apparatus is a printing apparatus that prints an image on the continuous medium,
While the printing apparatus interrupts the image printing process, the changing mechanism changes the moving distance by moving the moving roller in a direction intersecting the axis,
When the change mechanism is changed so as to shorten the moving distance, the feeding roller is rewound the continuous medium by the moving distance is shortened with the winding roller stopped.
The fluid ejecting apparatus according to claim 1, wherein the printing apparatus resumes the printing process after the feeding roller rewinds the continuous medium by an amount corresponding to the shortened moving distance. The fluid ejection device according to claim 5, wherein
The fluid ejecting apparatus is a printing apparatus that prints an image on the continuous medium,
While the printing apparatus interrupts the image printing process, the change mechanism changes the moving distance by moving the moving roller in a direction intersecting the axis,
When the change mechanism is changed so as to shorten the moving distance, the take-up roller takes up the continuous medium by the amount that the moving distance is shortened in a state where the feeding roller is stopped,
While the take-up roller is taking up the continuous medium as the moving distance is shortened, the printing apparatus is in a state where the feed roller is stopped and the second head is in the second facing position. The fluid ejecting apparatus according to claim 1, wherein the printing process is resumed by ejecting ultraviolet curable ink onto the region located. By transporting the medium, a second facing position where the second head that ejects a fluid having a color different from that of the first head is opposed to the area on the medium that is located at the first facing position where the first head faces. A transport method to move to
Changing the moving distance of the region from the first facing position to the second facing position;
Moving the region located at the first opposing position by the changed moving distance to be located at the second opposing position;
A conveying method characterized by comprising: