JP5898550B2 - Conveying mechanism and printing apparatus - Google Patents

Description

  The present invention relates to a transport mechanism and a printing apparatus that transport a print medium to which ink is attached.

  Conventionally, there is an ink jet printing apparatus as this type of apparatus. An inkjet printing apparatus includes an inkjet head that ejects ink droplets onto a print medium (for example, continuous paper), a mechanism that moves the inkjet head and the print medium relatively, and drying that dries the ink droplets attached to the print medium. And a section. The drying unit is composed of, for example, a heat drum (also referred to as a heat roller).

  The heat drum has a built-in heater and is heated to a preset temperature. The print medium is wound around the outer edge of the heat drum such that the surface (back surface) opposite to the surface on which the ink droplets adhere is in contact with the heat drum. Thereby, the heat drum can heat and dry the print medium from the back side of the print medium to which the ink droplets are attached. The heat drum is configured to be rotationally driven and conveys the print medium.

  Patent Document 1 discloses an ink jet recording apparatus that includes a unit that blows hot air on a recording medium to be conveyed and a preheating unit that heats the print medium upstream from a range in which the hot air flows. . Patent Document 2 discloses an ink jet recording apparatus including a suction-type platen in which a suction force is applied to the back surface of a sheet supported by the platen so that the sheet is brought into close contact therewith.

JP 2011-230494 A JP 2010-137399 A

  However, the conventional inkjet printing apparatus has the following problems. The print medium is conveyed by driving the drive roller. In general, the driving roller is pressed by a nip roller (pressing piece) from the opposite side across the print medium. Thereby, the grip force at the time of conveyance of a printing medium can be obtained. As with other drive rollers, when a gripping force is obtained by using a nip roller in a heat drum that is rotationally driven, the nip roller is provided on the downstream side in the print medium conveyance direction. However, when drying by the heat roller is insufficient, ink droplets adhere to the nip roller that contacts the surface of the printing medium on which the ink droplets adhere. For this reason, the other printing surface of the print medium is soiled by the nip roller to which the ink droplets adhere. Therefore, a grip force is obtained by applying tension to the print medium and pressing it against the heat drum without using a nip roller. However, in order to obtain a sufficient grip force, there is a desire to increase the pressing pressure as much as possible.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a transport mechanism and a printing apparatus capable of obtaining a grip force when transporting a print medium.

In order to achieve such an object, the present invention has the following configuration. That is, the transport mechanism according to the present invention includes a drive roller that rotates in contact with a surface of the print medium opposite to the surface on which the ink is adhered in the transport mechanism that transports the print medium on which the ink is adhered; A static pressure generator provided on the opposite side of the drive roller across the transport path for transporting the medium, and generating a static pressure by air toward the transport path , wherein the static pressure generator is A housing that covers a part of the transport path; a warm air blowing section that generates warm air and blows warm air toward the transport path in the housing; and an intake section that supplies air to the warm air spray section; Wherein the housing gradually increases the static pressure at the inlet of the housing and gradually decreases the static pressure at the outlet of the housing when the print medium passes through the housing. And it is characterized in that it comprises a static pressure adjusting member to maintain a static pressure by performing at least one of be.

According to the transport mechanism of the present invention, the static pressure generating unit is provided on the opposite side of the drive roller across the transport path for transporting the print medium, and generates static pressure by air toward the transport path. Since the print medium is pressed evenly against the drive roller by the static pressure of air, it is possible to obtain a grip force when the print medium is conveyed by the rotation of the drive roller. Moreover, since the static pressure by air is generated toward the conveyance path, it is possible to prevent the print medium from being soiled. Moreover, a static pressure can be generated in a housing by spraying warm air toward the conveyance path in the housing which covers a part of conveyance path. Further, since warm air is blown onto the conveyance path, warm air is blown onto the surface (surface) of the print medium to which the ink has adhered, and the ink attached to the print medium can be dried. Moreover, since the static pressure adjusting member is provided, the pressure in the housing can be maintained.

  In the transport mechanism of the present invention, it is preferable that the driving roller is a heat drum that is heated while being in contact with the surface of the printing medium opposite to the surface on which the ink is adhered and is rotated. Accordingly, the heat drum is heated in contact with the surface (back surface) opposite to the surface on which the ink of the printing medium is adhered, so that the ink adhered to the printing medium can be dried.

  Moreover, the conveyance mechanism of this invention WHEREIN: It is preferable that the said warm air blowing part is equipped with the nozzle which restrict | squeezes and blows warm air in the direction facing the said conveyance path | route. Thereby, the wind speed of the warm air to blow can be raised. Also, for example, an arbitrary air volume can be obtained even when the wind speed from the air source of the hot air blowing unit is slow. Further, the hot air can be uniformly supplied with the air volume distribution and the heat quantity of the hot air by being squeezed by the nozzle.

  Moreover, the conveyance mechanism of this invention WHEREIN: It is preferable that the said static pressure generation part is provided with the exhaust part which exhausts the warm air blown toward the said conveyance path | route by the said warm air blowing part. By exhausting the hot air blown toward the conveyance path, the hot air in the housing can be made to flow. Accordingly, in the housing of the static pressure generating unit, it is possible to give a large amount of air to the print medium and dry the ink attached to the print medium. On the other hand, the static pressure generating unit can generate a static pressure and press the print medium.

  In the transport mechanism of the present invention, it is preferable that the intake section circulates and uses the hot air collected by the exhaust section. The intake unit that supplies air to the hot air blowing unit circulates and uses the hot air collected by the exhaust unit. Therefore, since warm air is used rather than using outside air (fresh air), the warm air blowing unit can efficiently blow heated hot air.

  In the transport mechanism of the present invention, a plurality of the hot air blowing sections are provided along the transport path, and the exhaust section is configured to supply warm air blown to the transport path to supply the intake section. A hot air intake section for taking in air, wherein the hot air intake section is provided between a plurality of adjacent hot air blowing sections when a plurality of adjacent hot air blowing sections are combined. It is preferable. If air enters the hot air intake part from the other, the temperature of the hot air to be sucked will drop, but the hot air intake part is provided between the adjacent hot air blowing parts, so it is high It can inhale the warm air of temperature. Therefore, the warm air blowing unit can spray the heated warm air efficiently.

  Further, in the transport mechanism of the present invention, the hot air blowing section includes a blowing air source for blowing hot air, and the intake section is provided with an outside air inlet for taking in outside air, and the hot air intake is provided. It is preferable that an intake air supply source for intake of outside air is provided at a position closer to the outside air intake port than the section, and the intake air supply source is set to have a smaller air volume than the blowing air supply source. Thereby, an air volume difference is produced between the blowing air source and the intake air source, and the suction force for sucking in warm air from the hot air intake section can be generated by the air volume difference.

  Moreover, the conveyance mechanism of this invention WHEREIN: The said warm air blowing part is a heater provided facing the said conveyance path | route, the blowing air source for blowing the warm air which blows toward the said heater, and the said heater A heater housing that surrounds the inflow port through which the wind sent from the blowing air source flows, and warm air heated by the heater toward the transport path outside the heater housing along the transport path It is preferable to include the heater housing having a nozzle that is squeezed and sprayed in a different direction.

  Since the heater is surrounded by the heater housing, the heated air can be accumulated and can be efficiently heated. The blower source blows air toward the heater surrounded by the heater casing. The heater housing has an inflow port and a blowing port that blows hot air heated by the heater toward the transport path outside the heater housing in a direction along the transport path. The warm air can be raised at the blowing port to increase the speed of the warm air. Thereby, even when the wind speed from a ventilation source is slow, a desired wind speed can be obtained. Further, the hot air can be uniformly supplied with the air volume distribution and heat quantity of the hot air by being squeezed at the blowing port. Further, the heater is provided so as to face the conveyance path through which the print medium is conveyed. As a result, the distance to the transport path is relatively short, so that heat loss can be suppressed. Thereby, even in the case of a heater with a small heating power, it can be heated efficiently.

  In the transport mechanism of the present invention, it is preferable that the print medium is supplied from a roll of the print medium. If the gripping force of the driving roller is insufficient, slipping or the like occurs and the printing medium cannot be stably conveyed. For this reason, in the case of a print medium supplied from a roll of print medium, it is difficult to stably control the conveyance of the print medium together with other drive rollers. However, since the grip force is obtained at the static pressure generating portion, the conveyance control can be performed stably.

The printing apparatus of the present invention is a printing apparatus that prints on a printing medium, a driving roller that rotates in contact with a surface of the printing medium opposite to a surface on which ink is attached, and a conveyance that conveys the printing medium. A static pressure generator that is provided on the opposite side of the drive roller across the path and generates a static pressure by air toward the transport path, and the static pressure generator has a part of the transport path. A housing for covering, a hot air blowing unit that generates hot air and blows hot air toward the conveyance path in the housing, and an intake unit that supplies air to the hot air blowing unit, The housing has at least one of gradually increasing the static pressure at the inlet of the housing and gradually decreasing the static pressure at the outlet of the housing when passing the print medium through the housing. One of those it is characterized in that has a static pressure adjusting member to maintain the static pressure to go.

According to the printing apparatus according to the present invention, the static pressure generator is provided on the opposite side of the drive roller across the conveyance path through which the print medium is conveyed, and generates static pressure by air toward the conveyance path. Since the print medium is pressed evenly against the drive roller by the static pressure of air, it is possible to obtain a grip force when the print medium is conveyed by the rotation of the drive roller. Moreover, since the static pressure by air is generated toward the conveyance path, it is possible to prevent the print medium from being soiled. Moreover, a static pressure can be generated in a housing by spraying warm air toward the conveyance path in the housing which covers a part of conveyance path. Further, since warm air is blown onto the conveyance path, warm air is blown onto the surface (surface) of the print medium to which the ink has adhered, and the ink attached to the print medium can be dried. Moreover, since the static pressure adjusting member is provided, the pressure in the housing can be maintained.

  According to the transport mechanism and the printing apparatus according to the present invention, the static pressure generation unit is provided on the opposite side of the driving roller across the transport path for transporting the print medium, and generates static pressure by air toward the transport path. To do. Since the print medium is pressed evenly against the drive roller by the static pressure of air, it is possible to obtain a grip force when the print medium is conveyed by the rotation of the drive roller. Moreover, since the static pressure by air is generated toward the conveyance path, it is possible to prevent the print medium from being soiled.

1 is a schematic configuration diagram of an ink jet printing apparatus according to Embodiment 1. FIG. FIG. 3 is a side view illustrating a configuration of a drying unit according to the first embodiment. It is a side view which shows the structure of the warm air blowing unit of the drying part which concerns on Example 1. FIG. FIG. 3 is a plan view illustrating a configuration of a hot air blowing unit of a drying unit according to the first embodiment. FIG. 5 is a longitudinal sectional view of FIG. 4 illustrating the configuration of a hot air blowing unit of a drying unit according to the first embodiment. It is a figure with which it uses for operation | movement description of the warm air circulation of the warm air blowing unit of the drying part which concerns on Example 1. FIG. FIG. 6 is a side view illustrating a configuration of a drying unit according to Example 2.

  Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of an ink jet printing apparatus according to a first embodiment. FIG. 2 is a side view illustrating the configuration of the drying unit according to the first embodiment. 3 to 5 are a side view, a plan view, and a longitudinal sectional view of FIG. 4, respectively, illustrating the configuration of the hot air blowing unit of the drying unit according to the first embodiment.

  Please refer to FIG. The inkjet printing apparatus 1 includes an inkjet printing unit 2 that performs printing on a sheet-like continuous paper WP, a paper feeding unit 3 that supplies the continuous paper WP to the inkjet printing unit 2, and a continuous paper WP that has been printed in a roll shape. And a paper discharge unit 4 for winding. The continuous paper WP corresponds to the printing medium of the present invention, and the ink jet printing apparatus 1 corresponds to the printing apparatus of the present invention.

  The paper feed unit 3 holds a roll of continuous paper WP so as to be rotatable about a horizontal axis, and feeds the continuous paper WP from the roll of continuous paper WP to the inkjet printing unit 2 by unwinding. The paper discharge unit 4 winds the continuous paper WP printed by the inkjet printing unit 2 around the horizontal axis. When the supply side of the continuous paper WP is the upstream side and the discharge side of the continuous paper WP is the downstream side, the paper feed unit 3 is disposed upstream of the inkjet printing unit 2, and the paper discharge unit 4 is the inkjet printing unit 2. It is arranged downstream.

  The ink jet printing unit 2 includes a driving roller 7 for taking in the continuous paper WP from the paper feeding unit 3 on the upstream side. The continuous paper WP unwound from the paper feed unit 3 by the driving roller 7 is conveyed toward the downstream paper discharge unit 4 along a rotatable conveyance roller 9 having no driving mechanism. A driving roller 11 is disposed between an inspection unit 17 and a paper discharge unit 4 which will be described later. The drive roller 11 feeds the continuous paper WP that has passed through an inspection unit 17 described later toward the paper discharge unit 4.

  The inkjet printing unit 2 includes a printing unit 13, a drying unit 15, and an inspection unit 17 in that order from the upstream side between the driving roller 7 and the driving roller 11. Further, nip rollers 19 are rotatably provided on the drive rollers 7 and 11, respectively. The nip roller 19 presses the driving rollers 7 and 11 from the opposite side with the continuous paper WP interposed therebetween, thereby giving a grip force when the continuous paper WP is conveyed. The pressing force is given by, for example, an air cylinder. The nip roller 19 is made of an elastic body such as rubber. The drying unit 15 corresponds to the transport mechanism of the present invention.

  The printing unit 13 includes an inkjet head 21 that ejects ink droplets (ink). In the printing unit 13, a plurality of inkjet heads 21 are arranged in a staggered arrangement in the width direction (main scanning direction) 202 of the continuous paper WP orthogonal to the conveyance direction (sub-scanning direction) 201 of the continuous paper WP. As a result, ink droplets are ejected onto the continuous paper WP while the continuous paper WP is being fed while the position is fixed without moving the inkjet head 21 in the width direction 202 of the continuous paper WP. Hereinafter, a plurality of inkjet heads 21 arranged in a staggered arrangement in the width direction 202 of the continuous paper WP will be described as one inkjet head 21.

  In the printing unit 13, a plurality of inkjet heads 21 are arranged along the conveyance direction of the continuous paper WP. For example, four inkjet heads 21 are individually provided for black (K), cyan (C), magenta (M), and yellow (Y). An ink supply unit (not shown) is connected to the printing unit 13 and supplies ink droplets to the printing unit 13 as necessary.

  The drying unit 15 dries the ink droplets ejected from the inkjet head 21 and attached to the continuous paper WP. The drying unit 15 includes a heat drum 23 that is rotationally driven and a static pressure generation unit 25. The drying unit 15 will be described later. The inspecting unit 17 inspects the printed portion for dirt or missing. The inspected continuous paper WP is wound around the paper discharge unit 4 in a roll shape. The heat drum 23 corresponds to the drive roller of the present invention.

  The ink jet printing apparatus 1 includes a main control unit 27 and an operation unit 29. The main control unit 27 comprehensively controls each component of the inkjet printing apparatus 1 and includes a central processing unit (CPU) and the like. The operation unit 29 is for operating the ink jet printing apparatus 1 and includes, for example, a touch panel and various switches. The operation unit 29 may be configured by a personal computer and input an operation using a mouse, a keyboard, or the like. The drive rollers 7 and 11 and the heat drum 23 are rotationally driven by a drive mechanism such as a motor or a gear (not shown).

(Dry part)
Please refer to FIG. 2 and FIG. The drying unit 15 includes a heat drum 23 and a static pressure generation unit 25. The heat drum 23 includes a heater such as a halogen heater or a ceramic heater. The heat drum 23 is heated to a preset temperature by a heater. The heat drum 23 is made of a metal such as stainless steel. The heat drum 23 is heated in contact with the surface (back surface) opposite to the surface on which the ink droplets of the continuous paper WP are attached. At the same time, the heat drum 23 is driven to rotate. The continuous paper WP is wound around the outer edge 23 a of the heat drum 23. That is, the heat drum 23 heats from the back side of the continuous paper WP to dry the ink droplets while transporting the continuous paper WP.

  The static pressure generator 25 is provided on the opposite side of the heat drum 23 across the transport path 203 through which the continuous paper WP is transported, and generates a static pressure by air toward the transport path 203. In other words, the static pressure generating unit 25 presses the continuous paper WP against the heat drum 23 with static pressure by air to obtain a grip force when the continuous paper WP is conveyed. The static pressure generating unit 25 includes a housing 35 and a warm air blowing unit (also referred to as a warm air (hot air) drying unit) 37. The hot air blowing unit 37 is constituted by a plurality of adjacent (for example, two) hot air blowing portions 39 as a set.

  The housing 35 is configured to cover a part of the conveyance path 203, that is, a part of the outer edge 23 a of the heat drum 23. A gap 41 is provided between the outer edge 23a of the heat drum 23 and the housing 35 so that, for example, the continuous paper WP can pass therethrough. The continuous paper WP enters the area covered with the housing 35 from the inlet 35a on the upstream side of the conveyance path 203, and exits the area covered with the housing 35 from the outlet 35b on the downstream side of the conveyance path 203. Further, air (hot air) in the housing 35 leaks from the gap 41.

  The hot air blowing unit 39 is configured to blow hot air toward the conveyance path 203 in the housing 35. A plurality of hot air blowing sections 39 are provided along the outer edge 23 a of the heat drum 23, that is, along the conveyance path 203. As shown in FIGS. 2 to 5, the hot air blowing unit 39 includes a heater 43, a blowing fan 45, a heater housing (heater case) 47, and a blower duct 49. The blowing fan 45 corresponds to the blowing air source of the present invention.

  The heater 43 is provided to face the transport path 203 and heats the air. The heater 43 is constituted by, for example, a sheathed heater, but may be another heat source such as one that conducts electricity and generates heat. The blowing fan 45 blows air toward the heater 43. The blowing fan 45 is for blowing warm air. The blowing fan 45 is preferably composed of a combination of a plurality of fans in series, for example, a double reversing fan. As a result, the installation density is high and a large air volume is obtained, and there is a property that the air volume and the air speed are not lowered even if the air is sent to a place with resistance such as the heater housing 47. The blowing fan 45 may be an air source such as another fan or a blower.

  The heater housing 47 surrounds the heater 43. The heater housing 47 is opposed to the conveyance path 203 by the inlet 47a through which the wind sent from the blowing fan 45 flows and the warm air heated by the heater 43 toward the conveyance path 203 outside the heater casing 47. And a nozzle 47b that squeezes and blows in the direction. The heater housing 47 is configured such that the distance between the partition walls 47d becomes narrower in the direction along the transport path 203 as it goes toward the blowing port 47c at the tip of the nozzle 47b. The heater casing 47 and the nozzle 47b are configured separately, but may be configured integrally as the heater casing 47.

  The heater housing 47 is configured to substantially surround the heater 43 except for the inflow port 47a and the blowing port 47c, including the nozzle 47b. The heater housing 47 is made of a heat resistant material, for example, a metal such as stainless steel or a plastic coated with a heat resistant paint. The blowing port 47c is disposed close to the conveyance path 203 (for example, 10 mm). The nozzle 47 b of the heater housing 47 blows warm air perpendicularly to the transport path 203, that is, toward the axis 23 b of the rotating shaft of the heat drum 23.

  The blower duct 49 is provided between the blowing fan 45 and the inlet 47a of the heater housing 47, and allows the wind sent from the blowing fan 45 to flow into the inlet 47a of the heater housing 47.

  The static pressure generating unit 25 includes an exhaust duct 51 and an intake duct 53. The exhaust duct 51 corresponds to the exhaust part of the present invention, and the intake duct 53 corresponds to the intake part of the present invention.

  The exhaust duct 51 is provided outside the heater housing 47. The exhaust duct 51 exhausts the warm air blown toward the transport path 203 by the nozzle 47 b of the warm air blowing unit 39. That is, the exhaust duct 51 exhausts the hot air that is blown and reflected by the continuous paper WP conveyed on the conveyance path 203. The exhaust duct 51 exhausts the warm air collected outside the inkjet printing unit 2. The exhaust duct 51 is provided with an air source (not shown) such as a fan or a blower so as to forcibly exhaust air, but may be configured not to provide an air source if necessary.

  The intake duct 53 supplies air to the hot air blowing part 39. The intake duct 53 is configured to circulate and use the hot air collected at the hot air intake port 55. The hot air inlet 55 is configured to suck in hot air blown to the conveyance path 203 in order to supply to the intake duct 53. When a plurality of adjacent (for example, two) hot air blowing portions 39 are combined as one set, the hot air inlet 55 is provided between the adjacent (for example, two) hot air blowing portions 39. ing. The warm air that has been sucked and collected by the warm air inlet 55 passes through the intake duct 53 and is supplied to the blowing fan 45. The hot air intake port 55 corresponds to the hot air intake portion of the present invention.

  As shown in FIGS. 4 and 5, the intake duct 53 is provided with an outside air intake port 53 a that takes in outside air (fresh air) outside the intake duct 53, that is, outside the inkjet printing unit 2. In addition, the intake duct 53 is provided with an intake fan 57 for intake of outside air at a position closer to the outside air intake port 53a than the warm air intake port 55. The intake fan 57 includes a fan including a double reversing fan, a blower, and the like. The intake fan 57 corresponds to the intake air source of the present invention.

  The intake fan 57 is set to have a smaller air volume than the blowing fan 45. As a result, an air volume difference is generated between the blowing fan 45 and the intake fan 57, and a suction force for collecting the hot air from the hot air intake port 55 can be generated by the air volume difference.

  The blowing fan 45 and the intake fan 57 are controlled by the drying control unit 59 (FIG. 6). The drying control unit 59 is configured to change the air volume difference between the blowing fan 45 and the intake fan 57. That is, the drying control unit 59 controls the air volume difference by adjusting the rotation speed of the air volume from the blowing fan 45 and the air volume from the intake fan 57. Thereby, the mixing ratio of the warm air to circulate can be changed. The drying controller 59 is configured to control the heat drum 23 and the static pressure generator 25.

  As shown in FIGS. 4 and 5, the heater 43 is provided with a plurality of heaters having a long shape in the width direction 202 of the continuous paper WP. The heater 43 is configured with a length equal to or longer than the length in the width direction 202 of the continuous paper WP. As a result, a uniform amount of heat can be sent in the width direction 202 of the continuous paper WP. The heater housing 47 surrounds the heater 43, and includes an inflow port 47a that is long in the width direction 202 of the continuous paper WP and a blowing port 47c that has a slit-like opening that is long in the width direction 202 of the continuous paper WP. .

  The intake duct 53 is provided along the width direction 202 of the continuous paper WP, and a hot air intake port 55 is provided along the width direction 202 of the continuous paper WP. The intake duct 53 is provided in contact with the heater housing 47. Thereby, the air passing through the intake duct 53 can be heated.

  Reference numeral 61 denotes a hot air intake guide plate for intake of hot air. The hot air blowing unit 37 includes an intake duct 53, an outside air inlet 53a, an intake fan 57, and the like in addition to a plurality of (for example, two) hot air blowing portions 39 adjacent to each other. Or an exhaust duct 51 or the like.

  Next, the operation of the drying unit 15 of the inkjet printing apparatus 1 will be described. Please refer to FIG. The continuous paper WP is conveyed by the drive rollers 7 and 11 and the heat drum 23. When the continuous paper WP passes through the printing unit 13, ink droplets are ejected by the inkjet head 21 and printed. In this state, the ink droplets are not fixed on the continuous paper WP, and the continuous paper WP to which the ink droplets are attached is conveyed to the drying unit 15.

  In the drying unit 15 illustrated in FIG. 2, the continuous paper WP is conveyed in a state where the back surface thereof is in contact with the heat drum 23 and is wound around the outer edge 23 a of the heat drum 23. At this time, since the heat drum 23 is heated to a preset temperature, the continuous paper WP is heated by the heat drum 23 from the back side. As a result, the ink droplets adhering to the continuous paper WP are dried. At the same time, the ink droplets adhering to the continuous paper WP from the front side are dried by the two hot air blowing units 37 (that is, the four hot air blowing portions 39).

  The hot air blowing unit 39 blows hot air on the conveyance path 203 in the housing 35. Therefore, since warm air is blown to the surface (front surface) of the continuous paper WP on which the ink droplets are adhered, the ink droplets adhered to the continuous paper WP can be dried. Moreover, the hot air in the housing 35 can be flowed by exhausting the warm air blown toward the transport path 203 by the exhaust duct 51. As a result, in the housing 35 of the static pressure generating unit 25, it is possible to dry ink droplets attached to the continuous paper WP by giving a large air volume to the print medium.

  On the other hand, in the static pressure generating unit 25, since warm air is blown into the housing 35, the inside of the housing 35 can be set to a higher atmospheric pressure than the outside, and a static pressure can be generated. Therefore, the continuous paper WP can be pressed against the heat drum 23 with static pressure by air. Since static pressure is applied by air, it is possible to prevent the printed matter from being soiled. In addition, since the pressing is performed on a surface wider than the nip roller 19, the stress on the printed matter can be reduced when compared with the nip roller when the pressure is the same.

  Next, the operation of the hot air blowing unit 37 will be described. The hot air blowing unit 37 circulates and uses the hot air blown to the conveyance path 203. Therefore, since warm air is used rather than using outside air (fresh air), the warm air blowing unit 39 can efficiently blow heated hot air.

  As shown in FIGS. 3 and 5, the heater 43 is heated to a preset temperature. The heater 43 is surrounded by a heater housing 47. Therefore, since the air heated by the heater 43 is accumulated, the air can be efficiently heated. Wind is sent to the inlet 47a of the heater casing 47 surrounding the heater 43 by a blowing fan 45 with a blower duct 49 interposed therebetween.

  Further, the heater housing 47 is configured such that the distance between the partition walls 47d becomes narrower in the direction along the transport path 203 as it goes toward the blowing port 47c. Therefore, the air (warm air) heated and accumulated by the heater 43 is throttled by the heater casing 47. The hot air that has been squeezed is blown in a range in which the width direction 202 of the continuous paper WP becomes the longitudinal direction.

  The hot air blowing unit 39 blows the hot air heated by the heater 43 in a range where the width direction 202 of the continuous paper WP becomes the longitudinal direction. Drying with warm air depends on the wind speed, air volume, and heat quantity of the warm air, and is particularly effective when the wind speed is high. Further, the warm air containing the moisture that is blown and reflected by the continuous paper WP is collected by the exhaust duct 51 and exhausted. The temperature of the hot air is detected by a temperature sensor (not shown) disposed in the blowing port 47 c of the heater housing 47 and controlled by the drying control unit 59.

  Further, the intake duct 53 supplies air to the blowing fan 45 of the hot air blowing unit 39. Outside air is taken in by an outside air inlet 53 a provided in the intake duct 53. Intake of outside air is performed by an intake fan 57. Further, the hot air blown to the transport path 203 by the nozzle 47 b of the hot air blowing portion 39 is sucked into the intake duct 53 through the hot air intake port 55. The temperature of the hot air to be reused can be adjusted by changing the mixing ratio in the intake duct 53 and mixing the outside air and warm air sucked by the intake fan 57 provided in the intake duct 53. In addition, the temperature of the hot air blown from the nozzle 47b of the hot air blowing unit 39 can be adjusted by changing the mixing ratio of the outside air and the hot air.

  FIG. 6 is a diagram for explaining the operation of the hot air circulation of the hot air blowing unit. For example, the ratio of the air volume r from the blowing fan 45 is “2”, and the ratio of the air volume s from the intake fan 57 is “1”. Thereby, an air volume difference is generated between the blowing fan 45 and the intake fan 57. Due to this air volume difference, a suction force is generated at the hot air inlet 55. The ratio of the air volume t of the warm air collected at the warm air inlet 55 is “1”, so that the mixing ratio of the outside air and the collected warm air is 1: 1 (50%: 50%). be able to. Since the ratio of the air volume from the blowing fan 45 is “2”, warm air whose ratio of the air volume u is “2” is blown from the blowing port 47 c of the heater housing 47.

  According to the present embodiment, the static pressure generator 25 is provided on the opposite side of the heat drum 23 across the transport path 203 through which the continuous paper WP is transported, and generates a static pressure by air toward the transport path 203. . Since the continuous paper WP is pressed evenly against the heat drum 23 by the static pressure of the air, it is possible to obtain a grip force when the continuous paper WP is conveyed by the rotational drive of the heat drum 23. Moreover, since the static pressure by air is generated toward the conveyance path 203, it is possible to prevent the continuous paper WP from being soiled.

  The hot air blowing unit 39 includes a nozzle 47b that squeezes and blows hot air to the transport path 203 through a slit-like opening that is long in the width direction 202 of the continuous paper WP. Thereby, the wind speed of the warm air to blow can be raised. Further, for example, even when the wind speed from the blowing fan 45 of the warm air blowing unit 39 is low, an arbitrary air volume can be obtained. Further, the hot air can be uniformly supplied with the air volume distribution and the heat quantity of the hot air by being restricted by the nozzle 47b.

  A plurality of (for example, four) hot air blowing sections 39 are provided along the transport path 203, and the hot air intake port 55 includes a plurality of adjacent (for example, two) hot air blowing sections 39 as a set. In this case, it is provided between a plurality of (for example, two) adjacent hot air blowing portions 39. When air enters the hot air inlet 55 from the other, the temperature of the hot air to be sucked will decrease. However, since the hot air inlet 55 is provided between a plurality of (for example, two) adjacent hot air blowing portions 39, that is, sandwiched by the hot air from the hot air blowing portions 39, the temperature of the high temperature is high. Wind can be inhaled. Therefore, the warm air blowing unit 39 can spray the heated warm air efficiently.

  In addition, since the warm air sprayed is reused with the form of the warm air spraying unit 37 shown in FIGS. 3-5, the heater 43 can be labor-saving.

  The hot air blowing unit 39 includes a heater 43 provided facing the conveyance path 203, a blowing fan 45 for blowing warm air toward the heater 43, and a heater housing 47 that surrounds the heater 43. Thus, the hot air heated by the heater 43 is squeezed in the direction facing the conveyance path 203 toward the inlet 47a through which the wind sent from the blowing fan 45 flows and the conveyance path 203 outside the heater housing 47. A heater housing 47 having a nozzle 47b for spraying.

  Since the heater 43 is surrounded by the heater housing 47, the heated air can be accumulated and can be efficiently heated. The blowing fan 45 blows air toward the heater 43 surrounded by the heater housing 47. The heater housing 47 includes an inlet 47 a and a nozzle 47 b that blows hot air heated by the heater 43 toward the transport path 203 outside the heater housing 47 in a direction facing the transport path 203. ing. The warm air can be raised by the nozzle 47b to increase the speed of the warm air. Thereby, even when the wind speed from the blowing fan 45 is slow, a desired wind speed can be obtained. Further, the hot air can be uniformly supplied with the air volume distribution and the heat quantity of the hot air by being restricted by the nozzle 47b. Further, the heater 43 is provided so as to face the conveyance path 203 through which the continuous paper WP is conveyed. Therefore, since the distance to the conveyance path 203 is relatively short, heat loss can be suppressed. Thereby, even in the case of the heater 43 with small heating power, it can heat efficiently.

  The continuous paper WP is supplied from a roll of continuous paper WP. If the gripping force of the heat drum 23 is insufficient, slipping or the like occurs and the continuous paper WP cannot be stably conveyed. For this reason, in the case of the continuous paper WP supplied from the roll of the continuous paper WP, it is difficult to stably control the conveyance of the continuous paper WP together with the other drive rollers 7 and 11. However, since the grip force is obtained by the static pressure generator 25, the conveyance control can be performed stably.

  Next, Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 7 is a side view illustrating the configuration of the drying unit according to the second embodiment. In addition, the description which overlaps with Example 1 is omitted.

  In the second embodiment, in addition to the configuration of the first embodiment, when the continuous paper WP passes through the housing 35, the housing 35 gradually increases the static pressure at the inlet 35a of the housing 35 and at the outlet 35a of the housing 35. There is provided a static pressure adjusting member for maintaining the static pressure by performing at least one of gradually decreasing the static pressure.

  As shown in FIG. 7, as a static pressure adjusting member, for example, a guide plate 71 a is provided extending outside the housing 35 in order to gradually increase the static pressure at the inlet 35 a of the housing 35. Further, in order to gradually reduce the static pressure at the outlet 35 b of the housing 35, a guide plate 71 b is provided extending outside the housing 35. Accordingly, when the continuous paper WP is passed through the housing 35, the static pressure can be gradually increased and the static pressure can be gradually decreased. Therefore, the static pressure in the housing 35 can be maintained.

  Further, a punching metal having a large number of holes is provided in a part (for example, the inlet 35a side and the outlet 35b side) or all of the arc-shaped region 35c where the housing 35 covers the conveyance path 203 to suppress the passage of air. By doing so, the pressure may be prevented from being released. The punching metal is provided to such an extent that the function of the hot air blowing unit 39 is not lost, and the static pressure is maintained by changing the number or size of the holes.

  The housing 35 may include both guide plates 71a and 71b and a punching metal. In FIG. 7, a gap 41 is provided between the heat drum 25 and the housing 35, but the housing 35 has air (temperature) with respect to the heat drum 23 on the front side and the back side on the paper surface of FIG. 7. It is configured so that there is almost no leakage of wind.

  The present invention is not limited to the above embodiment, and can be modified as follows.

  (1) In each embodiment described above, the hot air blowing unit 37 is composed of two hot air blowing units 37 as shown in FIGS. 2 and 3, that is, four hot air blowing portions 39, but is not limited thereto. . The number of the hot air blowing units 37 is set according to the ease of drying the ink droplets of the continuous paper WP. For example, the three hot air blowing units 37 may constitute the static pressure generating unit 25.

  (2) In each of the above-described embodiments and modification (1), one hot air inlet 55 is provided in each intake duct 53 in FIG. 6, but four (plural) in FIG. 4. Hot air inlets 55 are respectively provided in the intake ducts 53. That is, the number of the warm air inlets 55 may be one or more.

  (3) In each of the above-described embodiments and modifications, the housing 35 covers all the hot air blowing portions 39, the exhaust duct 51, the intake duct 53, and the like. However, the housing 35 may be configured to cover at least the nozzle 47b, the exhaust duct 53, and the hot air inlet 55.

  (4) In each of the above-described embodiments and modifications, the hot air blowing unit 37 is composed of two adjacent hot air blowing portions 39 in FIGS. You may comprise by the spraying part 39. FIG. In this case, for example, the first hot air blowing part 39, the first hot air inlet 55, the second hot air inlet 55, the second hot air blowing part 39, the third hot air inlet 55, You may comprise in the order of the 3rd warm air spraying part 39. FIG.

  (5) In each example and each modification described above, the drying unit 15 has been described as an example of the transport mechanism, but is not limited thereto. For example, it is applied when transporting a continuous paper WP in which the attached ink droplets are not dried. In this case, it may not be heated as in the case of the heat drum 23 as necessary, and hot air may not be blown into the housing 35 (that is, cold air may be used).

  (6) In each of the above-described embodiments and modifications, the intake duct 53 circulates and reuses the hot air sucked at the hot air intake port 55. However, the hot air inlet 55 may be replaced with an exhaust duct, and the hot air blown to the transport path 203 may be exhausted to the outside of the inkjet printing unit 2.

  (7) In each of the above-described embodiments and modifications, the intake duct 53 circulates and reuses the hot air sucked at the hot air intake port 55. However, the hot air collected by the exhaust duct 51 may be supplied to the intake duct 53.

  (8) In each embodiment and each modification described above, the inkjet printing apparatus 1 supplies the continuous paper WP to the inkjet printing unit 2. However, separated paper may be supplied. Moreover, it is not limited to paper, A plastic film may be sufficient.

  (9) In each of the above-described embodiments and modifications, an inkjet printing apparatus has been described as an example of a printing apparatus. However, a printing apparatus such as a rotary press used for offset printing, gravure printing, or the like may be used.

DESCRIPTION OF SYMBOLS 1 ... Inkjet printer 13 ... Printing unit 15 ... Drying part 21 ... Inkjet head 23 ... Heat drum 23a ... Outer edge 25 ... Static pressure generating part 27 ... Main control part 35 ... Housing 35a ... Inlet 35b ... Outlet 37 ... Hot air spraying unit DESCRIPTION OF SYMBOLS 39 ... Hot air blowing part 43 ... Heater 45 ... Blowing fan 47 ... Heater housing 47a ... Inlet 47b ... Nozzle 47c ... Blowing port 51 ... Exhaust duct 53 ... Intake duct 53a ... Outside air intake port 55 ... Hot air intake port 57 ... Intake fan 59 ... Drying control unit 71a, 71b ... Guide plate

Claims (10)

In a transport mechanism that transports a print medium to which ink has adhered,
A driving roller that rotates in contact with a surface opposite to the surface on which the ink of the printing medium is attached;
A static pressure generation unit that is provided on the opposite side of the drive roller across a conveyance path through which the print medium is conveyed, and that generates a static pressure by air toward the conveyance path ,
The static pressure generator includes a housing that covers a part of the transport path;
A hot air blowing unit that generates hot air and blows hot air toward the transport path in the housing;
An air intake section for supplying air to the hot air blowing section,
The housing performs at least one of gradually increasing a static pressure at an inlet of the housing and gradually decreasing a static pressure at an outlet of the housing when passing the print medium through the housing. And a static pressure adjusting member for maintaining the static pressure . The transport mechanism according to claim 1,
The conveyance mechanism, wherein the driving roller is a heat drum that is heated while being in contact with a surface of the printing medium opposite to the surface on which the ink is adhered and is rotated. In the conveyance mechanism according to claim 1 or 2 ,
The transport mechanism, wherein the hot air blowing section includes a nozzle that squeezes and blows hot air in a direction facing the transport path. In the conveyance mechanism in any one of Claim 1 to 3 ,
The said static pressure generation part is provided with the exhaust part which exhausts the warm air sprayed toward the said conveyance path | route by the said warm air blowing part, The conveyance mechanism characterized by the above-mentioned. In the conveyance mechanism according to claim 4 ,
The conveyance mechanism characterized in that the intake section circulates and uses the hot air collected by the exhaust section. In the conveyance mechanism according to claim 5 ,
A plurality of the hot air blowing parts are provided along the transport path,
The exhaust unit is a hot air intake unit that draws in warm air blown to the conveyance path to supply the intake unit,
The said hot air intake part is provided between the adjacent several warm air spraying parts, when the said several adjacent warm air spraying part is made into 1 set, The conveyance mechanism characterized by the above-mentioned. The transport mechanism according to claim 6 ,
The hot air blowing section includes a blowing air source for blowing hot air, and the intake section is provided with an outside air intake port for taking in outside air, and is located closer to the outside air intake port side than the hot air intake section. An air supply source for intake of outside air at a position is provided, and the intake air supply source is set to have a smaller air volume than the blowing air source. In the conveyance mechanism in any one of Claim 1 to 7 ,
The warm air blowing part is
A heater provided facing the transport path;
A blowing air source for blowing warm air to blow toward the heater,
A heater housing that surrounds the heater, wherein an inflow port for introducing the wind sent from the blowing air source, and a hot air heated by the heater toward a transport path outside the heater housing The heater housing having a nozzle that squeezes and blows in a direction along
A transport mechanism comprising: In the conveyance mechanism in any one of Claim 1 to 8 ,
The transport mechanism according to claim 1, wherein the print medium is supplied from a roll of the print medium. In a printing apparatus for printing on a print medium,
A driving roller that rotates in contact with a surface opposite to the surface on which the ink of the printing medium is attached;
A static pressure generator provided on the opposite side of the drive roller across the transport path for transporting the print medium, and generating a static pressure by air toward the transport path ,
The static pressure generator includes a housing that covers a part of the transport path;
A hot air blowing unit that generates hot air and blows hot air toward the transport path in the housing;
An air intake section for supplying air to the hot air blowing section,
The housing performs at least one of gradually increasing a static pressure at an inlet of the housing and gradually decreasing a static pressure at an outlet of the housing when passing the print medium through the housing. And a static pressure adjusting member for maintaining the static pressure .

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