JP2009034927A - Inkjet printer - Google Patents

Abstract

To provide an ink jet printer capable of ensuring a long drying time of a paper without reducing the paper transport speed.
A drying unit U6 is configured to blow dry air W blown out of a housing 6 through a discharge port 47 of the housing 6 against print papers P1 and P2 placed on the discharge tray 5. To do.
[Selection] Figure 8

Description

  The present invention relates to an ink jet printer.

  Conventionally, as a means for printing characters and images (hereinafter collectively referred to simply as “images”), inkjet printers that print by reciprocating a print head that ejects ink in the width direction of the paper have been known. It has been.

  Here, if the paper after printing the image is stacked on the discharge tray in a state where the ink is not yet dried, the ink on the paper will not be dried uniformly and the printed image will be uneven in color or overlapped. Since problems such as ink adhering to the back side of the combined paper occur, it is necessary to sufficiently dry the paper and load it on the discharge tray.

Patent Document 1 discloses an infrared heater that dries ink landed on paper after image printing with thermal energy, and an air nozzle that blows air onto the surface of the paper heated by the infrared heater to lower the temperature. Inkjet printer technology including the above is disclosed.
JP 2001-270089 A

  However, in conventional ink jet printers, ink is dried only on the surface facing the infrared heater during paper transport. Therefore, in order to obtain the required drying capacity, the paper faces the infrared heater. Have to lengthen the time. That is, there is a problem in that the paper conveyance speed has to be slowed, and the processing capacity of the printer is reduced.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an ink jet printer that can ensure a long drying time of paper without reducing the paper conveyance speed. is there.

  In order to achieve the above-described object, in the present invention, the drying means blows the drying air onto the paper after image printing placed on the placing means.

  Specifically, the present invention is directed to an inkjet printer that prints an image on paper by ejecting ink from the print head onto the paper, and has taken the following solutions.

That is, the invention of claim 1 includes a housing having the print head and a discharge port for discharging the paper after image printing to the outside.
A drying means arranged in the housing and drying the paper by blowing dry air on the paper after image printing;
Mounting means for receiving the paper discharged through the discharge port of the housing;
The drying means is arranged in the vicinity of the discharge port of the casing, and is configured to blow dry air blown out of the casing through the discharge port against the paper placed on the mounting means. It is characterized by being.

  In this way, the drying means not only blows the drying air on the paper after the image is printed in the housing, but also blows the drying air after the paper is placed on the placing means, so that the drying air strikes the paper. Can be lengthened. That is, paper that has not been sufficiently dried in the housing can be dried even on the placing means, and can be efficiently dried. For this reason, when the paper is stacked on the loading means in a state where the ink is not yet dried, the color on the printed image caused by the ink on the paper not being dried uniformly or the back side of the superimposed paper This is advantageous in suppressing the adhesion of the ink.

The invention of claim 2 is the invention according to claim 1,
The placing means includes a transport belt for transporting the placed paper,
An accumulation means for accumulating the paper is provided on the downstream side of the conveyance belt in the conveyance direction.

  As described above, since the loading means is provided with a conveyance belt that conveys the paper, the paper placed on the conveyance belt is not overlapped by adjusting the conveyance speed, and the individual paper is dried. A long time can be secured. Further, by providing the stacking means on the downstream side of the transport belt, a larger number of papers can be accommodated. For this reason, the number of operations for the operator to remove the paper after image printing from the placing means is reduced, and the work efficiency is improved.

The invention of claim 3 is the invention of claim 2,
The position corresponding to the discharge port of the housing in the placing means is a placement region for receiving the paper immediately after being discharged through the discharge port,
The placing means retracts the already placed paper from the placement area before the paper to be discharged next through the discharge port of the housing is placed in the placement area. Thus, the conveying belt is driven as described above.

  In this way, before the paper to be discharged next through the discharge port of the housing is placed on the placement area of the placement means, the already placed paper is retracted from the placement area. When the conveyor belt is driven, the paper does not overlap on the conveyor belt, so that it is possible to suppress color unevenness or the like of the print image that occurs when the ink on the paper is not uniformly dried.

  Here, if the transport speed of the transport belt is made as slow as possible and the next paper is discharged when the already placed paper is retracted from the placement area, the paper on the transport belt is dried. It is preferable because a long time for blowing the wind can be secured. Instead of continuing to drive the transport belt at a constant speed, intermittent feeding may be performed in which the paper already placed when the next paper is transported is transported all at once to the outside of the placement area.

The invention of claim 4 is, in claim 2,
The placing means drives the transport belt so that the transport speed of the paper is equal to or higher than a predetermined speed at least when the paper is transferred from the transport belt to the stacking means.

  As described above, when the paper is transferred from the conveyance belt to the stacking unit, if the conveyance belt is driven so that the paper conveyance speed is equal to or higher than a predetermined speed, there is a gap between the conveyance belt and the stacking unit. Even so, paper can be reliably transferred by avoiding the paper from entering the gap.

  As described above, according to the inkjet printer of the present invention, the drying means not only blows the drying air in the housing against the paper after image printing but also the drying air after being placed on the placing means. By spraying, it is possible to lengthen the time during which the dry air strikes the paper. That is, paper that has not been sufficiently dried in the housing can be dried even on the placing means, and can be efficiently dried. For this reason, when the paper is stacked on the placing means in a state where the ink is not yet dried, the ink on the paper is not dried uniformly, and color unevenness of the printed image or the back side of the superimposed paper This is advantageous in suppressing the occurrence of problems such as ink adhesion.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature and is not intended to limit the present invention, its application, or its use.

<Embodiment 1>
FIG. 1 shows an external appearance of an inkjet printer A according to Embodiment 1 of the present invention, and FIGS. 2 to 7 show an internal configuration of the inkjet printer A. FIG. The inkjet printer A is used in a photographic print system. For example, print paper based on image data transmitted via a communication cable from a reception block that acquires image data and performs necessary correction processing and the like. Automatic printing that prints on P1 and P2, and pulls out one end of a long print paper P2 wound in a roll shape and prints on the print surface of the print paper P2 (hereinafter referred to as roll paper P2). It is configured to be able to execute printing and manual-feed printing that performs printing on a print surface (corresponding to a print surface) of a sheet-like print paper P1 (hereinafter referred to as sheet paper P1) that has been cut into a predetermined size in advance. Yes.

  In the following description, when it is not necessary to distinguish between the roll paper P2 and the sheet paper P1, the roll paper P2 and the sheet paper P1 are referred to as print papers P1 and P2. The printed surface means a surface on which printing is performed, and the printed surface of the sheet paper P1 is determined when the sheet paper P1 is set on the manual feed tray 81 (see FIG. 7). Specifically, when the sheet paper P1 is set on the manual feed tray 81, the surface facing upward is the print surface. In addition, the print surface of the roll paper P2 is a surface that faces radially outward when the roll paper P2 is wound in a roll shape.

-Overall configuration-
As shown in FIG. 7, the ink jet printer A includes a printer main body 90 and a manual feed tray 81 for manually setting and feeding the sheet paper P1 into the printer main body 90. The printer main body 90 is provided in the housing 6 and in the lower part of the housing 6, and the roll paper housing portion 1 (housing chamber) in which the roll paper P <b> 2 wound in a roll shape with the printing surface facing outside is housed. And the print surface of the sheet paper P1 supplied from the manual feed tray 81 or the roll paper P2 drawn out from the roll paper storage portion 1 provided on the upper portion of the housing 6 (upper side of the roll paper storage portion 1). The print unit 2 (see FIGS. 2 and 7) that performs printing on the print surface based on the image data, and the roll paper storage unit 1 at the bottom of the housing 6 An ink storage part 3 for storing ink to be supplied to the print unit 2 and a door member 95 that is attached to the housing 6 so as to be openable and closable, A roller unit 200 that conveys and feeds the sheet paper P1 set on the manual feed tray 81 toward the printing unit 2 when the member 95 is in the closed state.

  A roller cutter 41 for cutting unnecessary portions of the printed paper P1 and P2 after printing, and the print paper P1 and P2 on the downstream side in the transport direction of the printing unit 2 above the housing 6 The back side printing unit 4 for printing the reference number on the back side, the drying unit U6 for drying the print papers P1, P2 printed by the printing unit 2, and the printing papers P1, P2 printed by the printing unit 2 further downstream A discharge roller 46 is disposed to be conveyed to the side and discharged. On the downstream side of the discharge roller 46 in the paper conveyance direction, a discharge tray 5 (for receiving print papers P1 and P2 discharged from the discharge roller 46 and provided outside the discharge port 47 of the housing 6). Mounting means) is provided.

  In this embodiment, the side of the discharge tray 5 (the discharge side shown in FIG. 3) in the case 6 is referred to as the front side of the case, and the side opposite to the discharge tray 5 (the supply side shown in FIG. 3) is the rear side of the case. The left side when viewed from the front side of the casing is called the left side of the casing, and the right side is called the right side of the casing. Accordingly, the left-right direction in FIG. 7 is the front-rear direction of the casing, and the direction perpendicular to the paper surface of FIG. The lateral direction of the housing coincides with the width direction of the sheet paper P1 set and transported on the manual feed tray 81 and the width direction of the roll paper P2 stored and transported in the roll paper storage unit 1.

  The print unit 2 includes a print head H (see FIGS. 2 to 4 and 7) that forms an image by ejecting ink onto the print papers P1 and P2. The print head H is configured to be movable along a rail 30 that extends in a main scanning direction X (see FIG. 3) that coincides with the width direction of the print papers P1 and P2 (case left-right direction). Specifically, the rotational force of the drive motor 32 is transmitted to the drive belt 31 via a pulley, and the print head H moves in the main scanning direction X according to the rotation amount of the drive belt 31.

  The print head H has two head units 38 (lined up in a sub-operation direction Y (see FIG. 3) that is perpendicular to the main scanning direction X and coincides with the movement direction of the print papers P1 and P2 (front-rear direction of the casing). 7), and by ejecting ink from ink ejection nozzles (not shown) provided in these two head units 38, predetermined images, characters, etc. are applied to the print paper P1, P2. Can be printed.

  Each of the ink reservoirs 3 includes a box-shaped case 61 (see FIG. 4) disposed on both the left and right sides of the ink jet printer A. In the case 61, inks having different hues are sealed. Seven ink cartridges 62 are detachably accommodated (in FIG. 4, three cartridges are accommodated on the left side and four cartridges are accommodated on the right side). Therefore, by removing these ink cartridges 62 from the case 61, the used or used ones can be replaced with new ones. Each of these ink cartridges 62 includes yellow (Y), magenta (M), cyan (C), black (K), red (R), violet (V), and clear (CL: transparent) inks. Is enclosed.

  Further, on the left side when viewed from the discharge side of the ink jet printer A, a height position between the ink storage unit 3 and the print unit 2 is used for temporarily storing ink supplied from the ink cartridge 62. A sub tank 52 (see FIGS. 4 and 5) is provided. These sub tanks 52 are connected to the print head H of the print unit 2, and ink in the sub tank 52 is supplied to the print head H by negative pressure when ink is ejected from the nozzles of the print head H. It is like that.

-Paper transport mechanism-
As shown in FIG. 7, the ink jet printer A is provided with a paper transport mechanism that pulls in the sheet paper P1 from the manual feed tray 81 and transports it along a predetermined transport path. This paper transport mechanism includes a manual feed unit U5, a print unit U2, a cutter unit U3, a drying unit U6, and a discharge unit U4 in order from the manual feed tray to form the transport path. Image data is printed on the print surface of the print paper P1, P2 located on the transport path of the arranged print unit U2. In this embodiment, in addition to supplying the sheet paper P1 from the manual feed tray 81 to the print unit U2, the roll paper P2 can be pulled out from the roll paper storage unit 1 and conveyed to the print unit 2. A supply unit U1 configured as described above is also provided.

  When printing on the sheet paper P1, the paper transport mechanism transports and supplies the sheet paper P1 set on the manual feed tray 81 to the print unit U2 by the manual feed unit U5, and then supplies the supplied sheet paper P1 to the print unit. The image data is printed by the print head H while being conveyed by U2, and then the printed sheet paper P1 is conveyed to the cutter unit U3 and cut into a predetermined print size by the cutter unit U3, and then the drying unit U6. The sheet paper P1 is dried and sent out to the discharge tray 5 by the discharge unit U4. In the following description, the upstream side and the downstream side in the transport direction when the sheet paper P1 is transported during printing are simply referred to as the upstream side and the downstream side, respectively.

  The manual feed unit U5 includes a roller unit 200 for guiding the sheet paper P1 to the printing unit 2. The roller unit 200 includes a driving roller 202 and a driven roller 201. Then, the manual feed unit U5 guides the sheet paper P1 from the manual feed tray 81 into the printer main body 90 by rotating the drive roller 202.

  The supply unit U1 positions the roll paper P2 in the roll paper accommodating portion 1 in a roll shape and accommodates the roll paper P2 drawn out from the core roller 21 in the width direction. A width regulating roller 22 for carrying out, a closing roller 23 to be described later, a conveyance driving roller 24 that is rotationally driven so as to convey the roll paper P2 by an electric motor (not shown), and disposed opposite to the conveyance driving roller 24; Two pressure-bonding rollers 25 that are pressed against the conveyance drive roller 24 so as to sandwich the roll paper P <b> 2 between the conveyance drive roller 24 are provided.

  The supply unit U <b> 1 is configured to pull the roll paper P <b> 2 from the roll paper storage unit 1 and convey it to the printing unit 2 side by the rotation drive of the conveyance drive roller 24. In this embodiment, the width restricting roller 22 is provided, but a width restricting guide may be provided instead.

  The closing roller 23 is provided in order to ensure the airtightness of the roll paper container 1 and prevent the inside of the roll paper container 1 from being in a low humidity state. That is, a paper outlet opening for leading the roll paper P <b> 2 to the outside of the roll paper container 1 inside the housing 6 (that is, the print unit 2 side) is formed in a part of the wall that forms the roll paper container 1. 9 need to be formed. If the paper lead-out opening 9 is left open, the airtightness of the roll paper storage unit 1 cannot be ensured. Accordingly, the paper outlet opening 9 is provided with a closing roller 23 that closes the paper outlet opening 9 so that the roll paper P2 can pass therethrough.

  The closing roller 23 is formed of an elastically deformable material such as a foam material such as a sponge material or a rubber material at least at the outer peripheral portion, and the roll roller P2 passes through the paper lead-out opening 9. Thus, they are rotated in contact with each other while being elastically deformed radially inward. At this time, the roll paper P2 is pressed against the guide member 10 provided on the side opposite to the closing roller 23 (this pressing force is considerably small). In this way, the roll paper P2 can pass through the paper outlet opening 9 while receiving almost no resistance from the closing roller 23 while ensuring the airtightness of the roll paper container 1.

  The closing roller 23 may be configured to operate as a driving roller that actively feeds or rewinds the roll paper P2 in the transport direction. If the rotation driving force of the closing roller 23 can be transmitted to the closing roller 23 by an electromagnetic clutch (not shown) or the like, it is not necessary to provide a separate electric motor, and space saving of the apparatus can be achieved. It is advantageous for cost reduction.

  On the other hand, when the roll paper P2 is not present in the paper outlet opening 9, the closing roller 23 is in contact with the guide member 10, and at this time, the air tightness of the roll paper storage unit 1 is ensured. In this way, the roll paper container 1 in which airtightness is ensured is provided with a container 13 that contains water and is opened at the top, and the water in the container 13 is vaporized into water vapor to accommodate the roll paper. The inside of the part 1 is efficiently humidified.

  As a result, even when the ink jet printer A itself is placed under low humidity for a long time, the inside of the roll paper container 1 can be used in a moderate humidity (relative humidity range of 30 to 75%. Preferably 40 to 40%. 60%), it is possible to prevent the occurrence of curling such that the central portion in the width direction of the roll paper P2 protrudes toward the print surface with respect to both end portions in the width direction.

  The transport drive roller 24 is rotated in the forward direction to pull the roll paper P2 from the roll paper storage unit 1 and transport it to the print unit 2 side by an electric motor (not shown), and the roll paper P2 into the roll paper storage unit 1. The rotation in the reverse direction is possible.

  Thereby, after the printed part of the roll paper P2 is cut into a predetermined size by the cutter unit U3 on the downstream side of the print unit 2, the long roll paper P2 after the cutting is returned to the upstream side, and the roll paper P2 Printing is performed from the top of the paper, or the long roll paper P2 after cutting is returned to the roll paper storage unit 1, and the sheet-like print paper is supplied to the printing unit 2 by the manual feed unit U5 for printing. To be able to go. Further, when the long roll paper P2 is replaced with a new one, the long roll paper P2 drawn out of the roll paper storage unit 1 can be returned into the roll paper storage unit 1.

  The print unit U2 includes a paper holding part D (see FIGS. 3 and 7) for sucking and holding the print papers P1 and P2 at positions where printing can be performed by the print head H, and a downstream side of the paper holding part D. And a press-fitting type print transport roller 33 disposed in the head. The transport driving roller 24 and the pressure roller 25 of the supply unit U1 are also used as the print unit U2, and serve to transport the print papers P1 and P2 in the print unit U2.

  The paper holding part D sucks the platen 34 having a suction hole 34a (see FIG. 3) opened on the surface (upper surface) and the print papers P1 and P2 supplied onto the platen 34 by the supply unit U1. A fan 35 (see FIG. 7) is provided as a suction unit that sucks and holds the surface of the platen 34 by sucking through the hole 34a. The platen 34 is formed of a plate-like member, and a case body 36 that forms a space with the platen 34 is disposed on the back surface (lower surface) side of the platen 34, and the fan is disposed below the case body 36. 35 is disposed. The suction hole 34 a penetrates in the thickness direction of the platen 34 and communicates with a space in the case body 36, and this space communicates with the suction opening of the fan 35 through an opening provided in the lower portion of the case body 36. When the fan 35 is actuated, a negative pressure is generated on the surface side of the platen 34 through the suction hole 34a, whereby the print papers P1 and P2 are sucked and held on the surface of the platen 34.

  Further, the platen 34 has a flushing portion 37 (see FIG. 3) for receiving a small amount of ink ejected from the ink ejection nozzles of the head unit 38 in the print head H in order to prevent thickening of ink during printing, and non-printing. And a cap portion (not shown) configured to cover the ink discharge nozzles of the head unit 38 in the print head H in order to prevent thickening of the ink. ing.

  The flushing portion 37 is provided with an opening 37a (see FIG. 3) formed in the platen 34 and a lower side of the flushing portion 37 in the platen 34 to form a space communicating with the opening 37a. The case body communicates with a waste liquid tank 7 (see FIGS. 2 and 7) provided at the lower front side of the casing of the inkjet printer A. In addition, a sponge-like ink absorbing material 37b capable of absorbing ink is disposed in the opening 37a, and the ink soaked into the ink absorbing material 37b is also located below the flushing portion 37. It is designed to accumulate in the space inside the body. As a result, the ink ejected toward the opening 37a of the flushing portion 37 is guided to the waste liquid tank 7 after accumulating in the space inside the case body.

  The cap portion is not particularly shown, but when the cap portion covers the lower surface of the print head H, a space is formed in which a negative pressure is formed, and a small amount is formed in the space from the ink ejection nozzle. It is configured to suck out the ink. Accordingly, it is possible to prevent the ink from becoming difficult to be ejected due to the increase in the viscosity of the ink by the ink ejection nozzle.

  As described above, the print head H has a head unit 38 provided with a large number of ink discharge nozzles arranged in two stages in the sub-scanning direction Y on the bottom surface (the surface facing the platen 34). However, the head unit 38 does not have to be two stages, and may be one stage or three stages or more.

  Both the head units 38 have the same configuration, and are each composed of seven nozzle arrays arranged in the main scanning direction X for ejecting the inks of the respective colors. In each nozzle array, the ink discharge nozzles are arranged in a row in the sub-scanning direction Y. Accordingly, each head unit 38 is configured to be able to form a color image by itself. The print papers P1 and P2 are intermittently (stepwise) conveyed in the sub-scanning direction Y by a constant unit conveyance amount by the conveyance drive roller 24, and each stop of the print papers P1 and P2 during the intermittent conveyance is performed. Sometimes, the print head H is scanned once in the main scanning direction X (one-way operation or one-time operation), and ink is discharged from the ink discharge nozzles of each color of each head unit 38 at each position in the main scanning direction X during this scanning. Are simultaneously ejected onto the print surface of the print paper P1, P2. That is, after one scan of the print head H, the print papers P1 and P2 are transported by the unit transport amount, and then the print head H is scanned once again, and this operation is repeated to print a desired image. become. Here, as a configuration for ink discharge of the print head H in the present embodiment, ink is discharged from an ink discharge nozzle communicating with the pressure chamber by changing the volume of the pressure chamber filled with ink by a piezo element. The general piezo type is used.

  The cutter unit U3 includes a rotary blade 41, and the print paper P1 and P2 are moved in the width direction at predetermined positions in the length direction of the print paper P1 and P2 while rotating the rotary blade 41. It is configured to cut into a predetermined size (length). Below the rotary blade 41, a cutter waste collection box 65 for collecting chips of the print paper P1, P2 by cutting is disposed. The cutter waste collection box 65 can be taken out of the housing 6 by the operator holding the handle 66 and sliding it toward the front of the housing. The waste can be discarded. Note that the front side surface of the casing of the cutter waste collection box 65 is formed of a transparent plastic material so that the state of accommodation of the chips can be visually confirmed.

  In addition, the cutter unit U3 is configured to convey the print papers P1 and P2 to the discharge unit U4 by means of a pressure-type conveyance roller 43. A back side printing unit 4 is disposed between the cutter unit U3 and the discharge unit U4, and the back side printing unit 4 is arranged on the back side (lower side) of the print paper P1, P2 passing through this portion. Numbers etc. are printed.

  The discharge unit U4 has two sets of crimp type discharge rollers 46 and 46 for conveying the print papers P1 and P2 and discharging them to the discharge tray 5.

  As shown in FIG. 9, the discharge roller 46 is composed of a roller shaft 46a extending in the width direction of the print papers P1 and P2, and a plurality of roller portions 46b arranged at intervals in the axial direction of the roller shaft 46a. It is configured. The drying air W blown toward the downstream side in the paper transport direction by the drying unit U6 is vented to the discharge port 47 side from between the adjacent roller portions 46b and 46b.

  Hereinafter, the configuration of the drying unit U6, which is a characteristic part of the present invention, will be described with reference to FIG. A drying unit U6 for drying the print papers P1 and P2 by blowing dry air W onto the print papers P1 and P2 is provided between the two sets of pressure-bonding type discharge rollers 46 and 46 of the discharge unit U4. The drying unit U6 sucks air into the housing 6 from the suction port 48 formed in the vicinity of the upper portion of the discharge port 47 of the housing 6, heats the sucked air, and blows it as dry air W. . A dust collection filter 49 is attached to the suction port 48 to prevent dust in the air from being sucked into the drying unit U6.

  As shown in FIG. 8, the drying unit U6 includes a drying chamber 71 provided on the transport path of the print papers P1 and P2, and a drying device 72 (drying means) for blowing the drying air W to the drying chamber 71. I have. The drying chamber 71 is partitioned by an upper partition wall 71a and a lower partition wall 71b facing each other with the print papers P1 and P2 interposed therebetween, and the drying air W blown from the drying device 72 onto the print papers P1 and P2 is retained. It constitutes a staying space.

  The drying device 72 includes a plurality of suction fans 73 arranged at intervals in the left-right direction of the housing 6 in order to take air into the drying device 72 from outside through the suction port 48 of the housing 6, and the suction fans 73. A heater 74 that heats the air taken in, and is provided at the lower end of the drying device 72 and opens toward the downstream side in the paper conveying direction, and the drying air W heated by the heater 74 is moved downstream in the conveying direction. The exhaust nozzle part 75 which sprays and the safety thermo 76 which detects the temperature in the drying apparatus 72 and stops the heater 74 urgently are provided. Further, a heat insulating material 77 is provided on the upstream side in the paper transport direction of the outer wall of the main body of the drying device 72 including the exhaust nozzle portion 75. By providing such a heat insulating material 77, the heat radiated from the drying device 72 is transmitted to a unit that is weak against heat disposed on the upstream side in the paper conveyance direction, for example, the back surface printing unit 4 using an ink ribbon. Heating can be suppressed.

  The drying unit U6 sprays the drying air W toward the downstream side in the paper transport direction on the print papers P1 and P2 after image printing, and the blown drying air W passes through the discharge port 47 of the housing 6. It is comprised so that it may blow out to the housing | casing 6. The dry air W blown out of the housing 6 is blown against the print papers P1 and P2 placed on the discharge tray 5, as shown in FIG.

  By providing such a drying unit U6, even if the ink discharged from the print head H to the print papers P1 and P2 is not yet dried, the drying of the ink is promoted by blowing the drying air W. Can do. Since the drying air W is blown toward the downstream side in the paper transport direction, the time during which the drying air W is applied to the print papers P1 and P2 can be lengthened. That is, when the drying air W is blown perpendicularly to the print papers P1 and P2, the drying air W directly hits only the surface of the drying device 72 that faces the outlet of the exhaust nozzle portion 75. If the drying air W is blown toward the downstream side in the direction, the drying air W can be directly blown onto the print papers P1 and P2 that are moving toward the downstream side in the transport direction. The drying time can be ensured for a long time, and the drying can be performed efficiently. This is advantageous in preventing problems such as color unevenness occurring in the printed image because the ink does not dry uniformly when the print papers P1 and P2 are stacked on the discharge tray 5.

  Further, the dry air W sprayed on the print papers P1 and P2 is blown out of the housing 6 through the discharge port 47 of the housing 6 and is sprayed on the print papers P1 and P2 placed on the discharge tray 5. Therefore, the print papers P1 and P2 that have not been sufficiently dried in the drying chamber 71 can be dried on the discharge tray 5 and can be efficiently dried. Further, by blowing the drying air W out of the housing 6 from the discharge port 47, it is possible to prevent heat from being trapped inside the housing 6, and heat generated in the drying unit U6 is transferred to the back surface printing unit 4 and the like. Is preferable.

-Ink supply system-
As shown in FIG. 5, the ink supply system of the ink jet printer A is configured such that the ink in the ink cartridge 62 of the ink reservoir 3 located on both the left and right sides of the ink jet printer A is supplied to the sub tank via the electromagnetic valve 50 and the supply pipe 51. The ink in the sub tank 52 is sent out to the print head H through the flexible pipe 53.

  From the ink cartridge 62 to the sub tank 52, ink is sent out by pressurized air supplied into the ink cartridge 62 by a pressure pump (not shown), while from the sub tank 52 to the print head H, the print head The ink flows due to the negative pressure generated in the pressure chamber when the ink is ejected from the H nozzle.

  The sub-tanks 52 are formed in a bag shape using a flexible material such as a resin sheet, and seven sub tanks 52 are provided corresponding to seven types of inks having different hues. The seven sub tanks 52 are attached to the print head H at predetermined height positions so that ink is supplied to the print head H at an appropriate pressure.

  As described above, the ink in the ink cartridge 62 is temporarily stored in the sub tank 52 and then supplied from the sub tank 52 to the print head H. For this reason, the ink cartridge 62 can be replaced without interrupting printing. Moreover, since the sub tank 52 also serves as a pressure damper, it is possible to prevent the pressure fluctuation generated in the ink cartridge 62 from being directly transmitted to the print head H, and an excessive pressure is applied to the print head H. Can prevent ink leakage and the like from occurring.

  As described above, according to the inkjet printer A according to the first embodiment of the present invention, the drying unit U6 not only blows the drying air W on the print paper P1 and P2 after image printing in the housing 6. By blowing the drying air W even after it is placed on the discharge tray 5, the time during which the drying air W is applied to the print papers P1 and P2 can be lengthened. That is, the print papers P1 and P2 that have not been sufficiently dried in the housing 6 can be dried on the discharge tray 5 and can be efficiently dried. For this reason, when the print papers P1 and P2 are stacked on the discharge tray 5 in a state where the ink is not yet dried, the color unevenness of the print image caused by the ink on the print papers P1 and P2 not being dried uniformly. This is advantageous in suppressing the adhesion of ink to the back surfaces of the superimposed print papers P1 and P2.

<Embodiment 2>
FIG. 10 is a perspective view illustrating a configuration of an inkjet printer according to Embodiment 2 of the present invention. Since the difference from the first embodiment is that the transport unit 100 and the stacking unit 110 are provided instead of the discharge tray 5, hereinafter, the same parts as those of the first embodiment are denoted by the same reference numerals, and only the differences are described. explain.

  As shown in FIGS. 10 and 11, the inkjet printer A is disposed on the downstream side of the printer main body 90, the transport unit 100 disposed on the downstream side of the printer main body 90, and the transport direction of the transport unit 100. And an integrated unit 110. Note that the printer main body 90 has substantially the same configuration as that described in the first embodiment, and a description thereof will be omitted.

  The transport unit 100 constitutes a placing means for receiving the print papers P1 and P2 discharged from the discharge port 47 of the housing 6 of the printer main body 90, and the placed print papers P1 and P2 are disposed downstream. A conveyor belt 101 that conveys the conveyor belt 101 on the side and a driving roller 102 that drives the conveyor belt 101 are provided. Note that the downstream side in the transport direction of the transport unit 100 refers to the direction toward the right side of the housing 6.

  A position corresponding to the discharge port 47 of the housing 6 in the transport belt 101 is a placement region R for receiving the print papers P1 and P2 immediately after being discharged through the discharge port 47. The transport unit 100 is configured such that the print paper P1 that has already been placed before the print paper P1 and P2 to be discharged next through the discharge port 47 of the housing 6 is placed on the placement region R. , P2 is driven and controlled to retract P2 from the placement region R.

  Thereby, since the print papers P1 and P2 do not overlap on the transport belt 101, it is possible to suppress color unevenness or the like of the print image that is caused by the ink on the print papers P1 and P2 not being uniformly dried.

  The drive control of the transport belt 101 adjusts the transport speed so that the next print paper P1, P2 is discharged when the already placed print paper P1, P2 is retracted from the placement area R. Is done. That is, if the transport speed of the transport belt 101 is made as slow as possible, it is possible to secure a long time for the drying air W to be blown onto the print papers P1 and P2 on the transport belt 101.

  Instead of continuing to drive the transport belt 101 at a constant speed, when the next print papers P1 and P2 are transported, the print papers P1 and P2 already placed are transported out of the placement region R all at once. Intermittent feed may be used.

  The stacking unit 110 is disposed on the downstream side of the transport unit 100 in the transport direction, and stacks the print papers P1 and P2 transported from the transport unit 100. The stacking main body 111 and the stacking main body 111 A stacking plate 112 that is provided inside and on which the print papers P1 and P2 transported from the transport unit 100 are placed, and a plurality of stacking plates 112 that are spaced apart from each other are arranged in a belt conveyor manner in the rearward direction of the housing 6. And an integrated belt 113 that is conveyed.

  The stacking plate 112 waits so that the plate surface is horizontal and substantially flush with the belt surface of the transport belt 101 at the transfer position of the print papers P1 and P2 on the downstream side of the transport belt 101. After the number of sheets corresponding to the print order is collected, the next order print papers P1 and P2 are conveyed to the rear side of the housing 6 by the accumulation belt 113 before being conveyed. The plate surface of the accumulation plate 112 held horizontally rises in the middle of conveyance by the accumulation belt 113, and functions as a partition plate that partitions the print papers P1 and P2 for each print order.

  Here, the transport unit 100 transfers the print paper P1 and P2 from the transport belt 101 to the stacking plate 112 of the stacking unit 110 so that the transport speed of the print papers P1 and P2 is equal to or higher than a predetermined speed. The drive is controlled. Specifically, since a gap is provided between the conveyance belt 101 and the stacking plate 112, if the conveyance speed of the conveyance belt 101 is too slow, the edges of the print papers P1 and P2 enter the gap. Therefore, there is a possibility that smooth delivery cannot be performed or the delivery itself fails. Therefore, the transport speed of the transport belt 101 is controlled to be higher than the speed at which the print papers P1 and P2 can be stably delivered, so that the print papers P1 and P2 can be reliably delivered.

  As described above, according to the inkjet printer A according to the second embodiment of the present invention, the print papers P1 and P2 discharged from the discharge port 47 are placed on the placement region R of the transport belt 101 of the transport unit 100, While the transport speed of the transport belt 101 is made as slow as possible, the print papers P1 and P2 that have already been placed are placed before the print papers P1 and P2 to be discharged next are placed in the placement region R. Since it is made to evacuate from the region R, the dry air W blown from the discharge port 47 can be blown to the print papers P1 and P2 on the transport belt 101 for a long time, and the print papers P1 and P2 do not overlap. The print paper P1, P2 can be efficiently dried.

  Further, by providing the stacking unit 110 on the downstream side of the transport unit 100, a larger number of print papers P1 and P2 can be accommodated. For this reason, the number of operations for the operator to remove the print papers P1, P2 after image printing is reduced, and the work efficiency is improved.

  Further, after the number of print papers P1 and P2 corresponding to a predetermined print order is accumulated on the accumulation plate 112 of the accumulation unit 110, before the next order print papers P1 and P2 are conveyed, the accumulation plate 112 is collected. Is arranged so as to be partitioned for each print order, so that the print papers P1 and P2 for each order can be easily arranged. For this reason, it is not necessary for the operator to manually sort the print papers P1 and P2 for each order after all the printing processes are completed, and the work load is reduced.

  As described above, the present invention provides a highly practical effect that can provide an ink jet printer capable of ensuring a long drying time of paper without reducing the paper conveyance speed. It is extremely useful and has high industrial applicability.

1 is a perspective view showing an appearance of an ink jet printer as an image forming apparatus according to Embodiment 1 of the present invention. It is a perspective view which shows the structure inside the housing | casing of an inkjet printer. It is a top view which shows the structure inside the housing | casing of an inkjet printer. It is a front view which shows the structure inside the housing | casing of an inkjet printer. It is a left view which shows the structure inside the housing | casing of an inkjet printer. It is a rear view which shows the structure inside the housing | casing of an inkjet printer. It is the schematic seen from the housing | casing left side which shows the conveyance path | route of a print paper. It is sectional drawing seen from the housing | casing left side which shows the structure of a drying unit. It is a top view explaining the blowing state of dry wind. It is a perspective view which shows the external appearance of the inkjet printer which concerns on this Embodiment 2. FIG. It is a top view which shows the external appearance of an inkjet printer.

Explanation of symbols

A Inkjet printer P1 Sheet paper P2 Roll paper H Print head R Placement area W Dry air 5 Discharge tray (placement means)
6 Housing 47 Discharge port 72 Drying device (drying means)
100 transport unit (mounting means)
101 Conveying belt 110 Stacking unit (stacking means)
112 integration plate

Claims (4)

An inkjet printer that prints an image on a paper by discharging ink from the print head to the paper,
A housing containing the print head and having a discharge port for discharging the paper after image printing to the outside;
A drying means arranged in the housing and drying the paper by blowing dry air on the paper after image printing;
Mounting means for receiving the paper discharged through the discharge port of the housing;
The drying means is arranged in the vicinity of the discharge port of the casing, and is configured to blow dry air blown out of the casing through the discharge port against the paper placed on the mounting means. An ink jet printer characterized by being made. In claim 1,
The placing means includes a transport belt for transporting the placed paper,
An ink jet printer characterized in that a stacking means for stacking the paper is provided on the downstream side in the transport direction of the transport belt. In claim 2,
The position corresponding to the discharge port of the housing in the placing means is a placement region for receiving the paper immediately after being discharged through the discharge port,
The placing means retracts the already placed paper from the placement area before the paper to be discharged next through the discharge port of the housing is placed in the placement area. An ink jet printer configured to drive the transport belt as described above. In claim 2,
The placing means is configured to drive the transport belt so that the transport speed of the paper is equal to or higher than a predetermined speed at least when the paper is transferred from the transport belt to the stacking means. Inkjet printer.

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