JP2020050455A - Web support device, print device, and web support method - Google Patents

Abstract

To provide a web support device, a print device, and a web support method capable of preventing a web from contacting a conveyor surface because of pressure drop at an end of the web.SOLUTION: A web support device is provided with two leak prevention members 96 clamping a printing medium M opposing to a conveyor surface 93 from a width direction Dw, wherein the leak prevention members 96 receive gas G leaking from a gap 95 between the conveyor surface 93 and the printing medium M to the width direction Dw. Thereby, the gas G is prevented from leaking by the leak prevention member 96 to secure pressure on an edge of the printing medium M. As a result, the printing medium M can be prevented from contacting the conveyor surface 93 because of pressure drop at an end of the printing medium M.SELECTED DRAWING: Figure 9

Description

  The present invention relates to a floating support technique for supporting a web, which is conveyed along a conveying surface formed of a curved surface, while being floated by gas ejected from a plurality of holes opened in the conveying surface.

  Conventionally, in order to avoid damage to the web, a web support device such as an air turn bar that conveys the web while floating the web has been used. As described in Patent Literature 1, this web support device ejects a gas such as air from a plurality of holes provided in a transport surface to a web transported along a transport surface configured with a curved surface. This causes the web to float on the transport surface.

JP 2013-23371 A

  In order to ensure that the web is levitated by such a web supporting device, it is necessary to sufficiently generate pressure caused by gas injection between the web and the conveying surface. However, at the end of the web, the pressure drops due to the gas flowing out from the gap between the transport surface and the web, and the web may come into contact with the transport surface.

  The present invention has been made in view of the above problems, and has as its object to provide a technique capable of suppressing a web from coming into contact with a conveyance surface due to a pressure drop at an end of the web.

  The web support device according to the present invention has a transport surface formed of a curved surface, and is provided with a gas ejected from a plurality of holes opened in the transport surface with respect to a web transported in a predetermined transport direction along the transport surface. While floating the web from the transport surface, the body portion that supports the web, and two outflow suppression members that are arranged at intervals in the width direction orthogonal to the transport direction and sandwich the web facing the transport surface from the width direction, The outflow suppressing member receives gas flowing out in the width direction from a gap between the transport surface and the web.

  In the web supporting method according to the present invention, the web conveyed in a predetermined conveying direction along a conveying surface formed of a curved surface causes the web to float from the conveying surface by gas ejected from a plurality of holes opened in the conveying surface with respect to the web. While supporting the web, the transport surface and the web are separated by two outflow suppressing members that are arranged at intervals in the width direction orthogonal to the transport direction and that sandwich the web facing the transport surface from the width direction. Receiving the gas flowing out from the gap in the width direction.

  In the present invention (web supporting device and web supporting method) configured as described above, two outflow suppressing members that sandwich the web facing the conveying surface from the width direction are provided, and the outflow suppressing members are connected to the conveying surface and the web. From the gap in the width direction. Thus, the outflow of the gas is suppressed by the outflow suppressing member, and the pressure at the end of the web is secured. As a result, it is possible to suppress the web from coming into contact with the transport surface due to the pressure drop at the end of the web.

  Further, the web support device may be configured such that the wall of the outflow suppressing member on the web side in the width direction is longer in the normal direction of the transport surface than the gap between the transport surface and the web. Thus, the outflow of the gas can be accurately suppressed by the outflow suppressing member, and the pressure at the end of the web can be more reliably secured.

  Further, the web support device may be configured such that the distance between the outflow suppressing member and the web in the width direction is shorter than the length of the gap between the transport surface and the web in the normal direction of the transport surface. In such a configuration, the outflow suppressing member is arranged close to the web. Therefore, the outflow of the gas can be accurately suppressed by the outflow suppressing member, and the pressure at the end of the web can be more reliably secured.

  Further, the web support device may be configured such that at least one of the two outflow suppressing members is a movable outflow suppressing member movable in the width direction with respect to the body. In such a configuration, by moving the outflow suppressing member according to the width of the web, the outflow suppressing member can be arranged close to the web. Therefore, regardless of the width of the web, the outflow of the gas is accurately suppressed by the outflow suppressing member, and the pressure at the end of the web can be more reliably ensured.

  Further, the web supporting device may be configured such that the movable outflow suppression member is configured to close a hole provided outside a range between the two outflow suppression members in the width direction. . Thereby, the holes that do not contribute to the floating of the web can be closed, and the loss of pressure due to the holes can be suppressed.

  In addition, the web support device may be configured such that the wall of the outflow suppressing member on the web side in the width direction is parallel to the normal direction of the transport surface. In such a configuration, the outflow of gas from the gap between the conveying surface and the web can be accurately suppressed by the wall of the outflow suppressing member, and the pressure at the end of the web can be more reliably ensured.

  A printing device according to the present invention includes a printing unit that discharges ink onto a web, a drying unit that dries the web that has been discharged with the ink by the printing unit, and the web support device described above. To support the web. Therefore, it is possible to suppress the web from coming into contact with the transport surface due to the pressure drop at the end of the web.

  As described above, according to the present invention, it is possible to suppress the web from coming into contact with the transport surface due to the pressure drop at the end of the web.

FIG. 1 is a front view schematically illustrating an example of a printing apparatus according to the invention. FIG. 2 is a front view schematically illustrating a first-stage printing unit and a first-stage drying unit included in the printing apparatus in FIG. 1. FIG. 2 is a front view schematically illustrating a first-stage drying unit and a second-stage printing unit included in the printing apparatus in FIG. 1. FIG. 2 is a front view schematically illustrating a rear printing unit and a rear drying unit included in the printing apparatus in FIG. 1. FIG. 2 is a front view schematically showing a rear-stage drying unit provided in the printing apparatus in FIG. 1. FIG. 6 is a perspective view schematically showing the appearance of the air turn bar. FIG. 4 is a view schematically showing the air turn bar developed in the transport direction of the print medium folded by the air turn bar. FIG. 3 is a diagram schematically illustrating a cross section of an air turn bar and a print medium. The figure which expands the vicinity of the outflow suppression member of an air turn bar, and is shown typically. The figure which shows the 1st modification of an air turn bar typically. The figure which shows the 2nd modification of an air turn bar typically.

  FIG. 1 is a front view schematically showing an example of a printing apparatus according to the present invention. In FIG. 1 and the following drawings, the horizontal direction X and the vertical direction Z are appropriately shown. As shown in FIG. 1, the printing apparatus 1 includes a first-stage printing unit 2, a first-stage drying unit 4, a second-stage printing unit 6, and a second-stage drying unit 8 having the same height in the horizontal direction X (arrangement direction) in this order. It has an arrayed configuration. The printing apparatus 1 dries the print medium M printed in the pre-stage printing unit 2 in the pre-stage drying unit 4 while conveying the print medium M from the feeding roll 11 to the take-up roll 12 in a roll-to-roll manner. The printing medium M printed by the printing unit 6 is dried by the subsequent drying unit 8. Various materials such as paper and film can be used as the print medium M. In the following, of the two surfaces of the print medium M, the surface on which an image is printed is referred to as the front surface, and the surface opposite to the front surface is referred to as the back surface.

  FIG. 2 is a front view schematically illustrating a pre-stage printing unit and a pre-stage drying unit included in the printing apparatus of FIG. In the pre-stage printing unit 2, the transport direction Dm of the print medium M goes from right to left in FIG. The pre-printing unit 2 includes a carry-in roller 21 that carries in the print medium M fed from the pay-out roll 11 and a carry-out roller 23 that carries out the print medium M toward the pre-drying unit 4. The carry-in roller 21 and the carry-out roller 23 wind the back surface of the print medium M from below and drive the print medium M in the transport direction Dm. Further, the first-stage printing unit 2 has a plurality of backup rollers 25 arranged between the carry-in roller 21 and the carry-out roller 23 in the carrying direction Dm. Each of these backup rollers 25 supports the print medium M by winding the back surface of the print medium M transported in the transport direction Dm from below.

  Among the plurality of backup rollers 25, a first-stage printing path Pa is formed between the most upstream backup roller 25 and the most downstream backup roller 25 in the transport direction Dm. The upstream and downstream backup rollers 25 support the print medium M at the same height as each other, and support the print medium M at a higher position as the backup roller 25 inside the preceding printing path Pa. Therefore, the preceding printing path Pa has a curved shape that is convex upward.

  Further, the first-stage printing unit 2 includes a plurality of ejection heads 27 arranged in the conveying direction Dm above the print medium M conveyed along the first-stage print path Pa and facing the surface of the print medium M. Specifically, the ejection heads 27 are arranged on the surface of the print medium M that advances between two adjacent backup rollers 25, and each ejection head 27 is thus separated by two backup rollers 25 on both sides. Ink is ejected onto the surface of the supported printing medium M by an inkjet method. In the example shown here, four ejection heads 27 that eject four process color (yellow, magenta, cyan, and black) inks, and two ejection heads that eject two color (orange, violet) special color inks Six ejection heads 27 including the head 27 are provided. Therefore, the first-stage printing unit 2 can print a color image on the surface of the print medium M by the six ejection heads 27 that eject inks of different colors from each other.

  The print medium M on which the image has been printed in the first-stage printing path Pa descends obliquely between the backup roller 25 and the discharge roller 23 at the most downstream side of the first-stage printing path Pa and reaches the discharge roller 23. The carry-out roller 23 winds the back surface of the print medium M from below at the downstream of the plurality of backup rollers 25 in the transport direction Dm. Then, the carry-out roller 23 carries out the print medium M to the pre-stage drying unit 4 along the pre-stage carry-out path Pab in which the print medium M diagonally descends in the transport direction Dm. The unloading roller 23 is a suction roller that sucks the back surface of the printing medium M, and suppresses the transmission of the vibration of the printing medium M from the pre-stage drying unit 4 to the pre-stage printing unit 2 to reduce Stabilize the position of the print medium M. As a result, it is possible to suppress the transport of the print medium M in the pre-stage drying unit 4 from affecting the printing in the pre-stage printing unit 2.

  FIG. 3 is a front view schematically showing a pre-stage drying unit and a post-stage printing unit included in the printing apparatus of FIG. The pre-stage drying unit 4 dries the print medium M while appropriately folding the transport direction Dm of the print medium M in the vertical direction Z. The pre-stage drying unit 4 has a carry-in roller 41 for winding the print medium M carried out from the pre-stage print unit 2 along the pre-stage carry-out path Pab (FIG. 2) from the back surface. The transport direction Dm is bent downward parallel to the vertical direction Z.

  Further, the pre-stage drying unit 4 includes a pair of air turn bars 42 and 43 that folds the print medium M descending from the carry-in roller 41 in the vertical direction Z upward in the vertical direction Z. Of the pair of air turn bars 42, 43, the air turn bar 42 on the upstream side in the transport direction Dm bends the print medium M descending from the carry-in roller 41 along the vertical direction Z in the horizontal direction X, and on the downstream side in the transport direction Dm. The air turn bar 43 folds the print medium M moving in the horizontal direction X from the air turn bar 42 upward in parallel with the vertical direction Z. Therefore, the print medium M that has passed through the air turn bar 43 is transported along the rising and drying path Pb1 that rises in the vertical direction Z. Each of the air turn bars 42 and 43 winds around the surface of the print medium M while providing a gap to the surface of the print medium M by jetting air. Thus, the print medium M can be folded back by the air turn bars 42 and 43 while suppressing the influence on the image printed on the surface of the print medium M.

  The pre-stage drying unit 4 includes a pair of rollers 44 and 45 that fold the print medium M that rises in the vertical direction Z along the upward drying path Pb1 downward in parallel with the vertical direction Z. Of the pair of rollers 44, 45, the roller 44 on the upstream side in the transport direction Dm bends the print medium M rising along the rising and drying path Pb1 in the horizontal direction X, and the roller 45 on the downstream side in the transport direction Dm is The print medium M moving in the horizontal direction X from the roller 44 is bent downward in parallel with the vertical direction Z. Therefore, the print medium M that has passed through the rollers 45 is transported along the descending drying path Pb2 that descends in the vertical direction Z. Each of the rollers 44 and 45 winds the back surface of the print medium M.

  Further, the pre-stage drying unit 4 has an air turn bar 46 that bends the print medium M descending along the descending drying path Pb2 in the horizontal direction X. Therefore, the print medium M that has passed through the air turn bar 46 is carried out from the first drying unit 4 to the second printing unit 6 along the horizontal direction X. The air turn bar 46 winds around the surface of the print medium M while providing a gap to the surface of the print medium M by jetting air. Thereby, the print medium M can be folded back by the air turn bar 46 while suppressing the influence on the image printed on the surface of the print medium M.

  Further, the pre-stage drying unit 4 has a pre-stage heater H4 for drying the ink adhered to the surface of the print medium M for each of the ascending drying route Pb1 and the descending drying route Pb2. The front heater H4 facing the ascending drying path Pb1 dries the surface of the printing medium M passing through the ascending drying path Pb1, and the preceding heater H4 facing the descending drying path Pb2 uses the printing medium M passing through the descending drying path Pb2. Dry the surface. Further, the pre-stage drying unit 4 includes a pre-stage heater H4 for drying the surface of the print medium M descending between the carry-in roller 41 and the air turn bar 42. The pre-stage drying unit 4 dries the ink discharged to the print medium M in the pre-stage printing unit 2 by the pre-stage heater H4 arranged as described above.

  FIG. 4 is a front view schematically showing a post-stage printing unit and a post-stage drying unit included in the printing apparatus of FIG. The rear printing unit 6 includes an air turn bar 61 that bends the print medium M carried out in the horizontal direction X from the front drying unit 4 obliquely upward. The air turn bar 61 winds around the surface of the print medium M while providing a gap to the surface of the print medium M by jetting air. Thereby, the print medium M can be folded back by the air turn bar 61 while suppressing the influence on the image printed on the surface of the print medium M. The post-printing unit 6 includes a discharge roller 63 that conveys the print medium M toward the post-drying unit 8, and a transport roller 65 that is disposed between the air turn bar 61 and the discharge roller 63. The transport roller 65 and the discharge roller 63 wind the back surface of the print medium M from below and drive the print medium M in the transport direction Dm. Then, as the print medium M advances from the transport roller 65 to the discharge roller 63, the print medium M rises obliquely.

  Further, the post-stage printing unit 6 has two backup rollers 67 between the transport roller 65 and the discharge roller 63. A post-print path Pc is formed between the two backup rollers 67. These backup rollers 67 are provided for the upward inclination from the transport roller 65 to the carry-out roller 63, and form a second-stage printing path Pc in which the print medium M rises obliquely as it advances in the transport direction Dm.

  Further, the post-printing unit 6 includes an ejection head 69 that faces the surface of the print medium M above the print medium M conveyed along the post-print path Pc. Specifically, the ejection head 69 is disposed on the surface of the print medium M that travels between the two backup rollers 67, and the ejection head 69 is thus supported on both sides by the two backup rollers 67. Ink is ejected onto the surface of the print medium M by an inkjet method. In the example shown here, the backup roller 67 discharges white ink. Therefore, the second-stage printing unit 6 can print a white background image on the surface of the print medium M with respect to the color image printed by the first-stage printing unit 2.

  The print medium M on which an image has been printed in the second-stage printing path Pc rises obliquely between the backup roller 67 and the discharge roller 63 at the most downstream side of the second-stage printing path Pc, and reaches the discharge roller 63. The carry-out roller 63 winds the print medium M from below on the downstream side of the two backup rollers 67 in the transport direction Dm. The carry-out roller 63 winds the print medium M that has risen obliquely from the post-stage printing path Pc in this way, so that the print medium M moves along the rear-stage carry-out path Pcd in which the print medium M moves in the horizontal direction X. To be carried out. The unloading roller 63 is a suction roller that sucks the back surface of the print medium M, and suppresses transmission of the vibration of the print medium M from the post-stage drying unit 8 to the post-stage printing unit 6 so as to suppress the transmission of the post-stage printing path Pc. Stabilize the position of the print medium M. As a result, it is possible to suppress the conveyance of the print medium M in the downstream drying section 8 from affecting the printing in the downstream printing section 6.

  FIG. 5 is a front view schematically illustrating a rear drying unit included in the printing apparatus in FIG. 1. The second drying unit 8 includes a first unit 81 disposed downstream of the second printing unit 6 in the transport direction Dm, and a second unit 82 detachably connected to the first unit 81. Thus, in the horizontal direction X (arrangement direction), the post-stage printing unit 6, the first unit 81, and the second unit 82 are arranged in this order. The latter-stage drying unit 8 dries the print medium M while appropriately turning the transport direction Dm of the print medium M in the horizontal direction X. That is, the rear drying unit 8 performs the upper drying path Pd1 in which the print medium M moves horizontally in the one direction X1 of the horizontal direction X, and the other drying X2 in the horizontal direction X (the direction opposite to the one direction X1) from the upper drying path Pd1. A middle drying path Pd2 in which the folded print medium M moves horizontally below the upper drying path Pd1, and a lower step in which the printing medium M folded in one direction X1 from the middle drying path Pd2 moves horizontally below the middle drying path Pd2. And a drying path Pd3.

  The first unit 81 has a pair of rollers 811 and 812 arranged according to the height of the upper drying path Pd1, and the second unit 82 has a pair of rollers arranged according to the height of the upper drying path Pd1. It has rollers 821 and 822. That is, the rollers 811 and 812 of the first unit 81 and the rollers 821 and 822 of the second unit 82 are arranged in this order in one direction X1, and the upper drying path is at the same height as the post-unloading path Pcd (FIG. 4). Pd1 is formed, and the print medium M carried out from the rear printing section 6 along the rear carrying path Pcd is horizontally conveyed in one direction X1 along the upper drying path Pd1.

  The second unit 82 has a pair of rollers 823 and 824 arranged according to the height of the middle drying path Pd2, and the first unit 81 is arranged according to the height of the middle drying path Pd2. It has a roller 813 and an air turn bar 814. That is, the rollers 823 and 824 of the second unit 82, the roller 813 and the air turn bar 814 of the first unit 81 are arranged in this order in the other direction X2 to form the middle drying path Pd2, and are folded from the upper drying path Pd1. The print medium M is horizontally conveyed in the other direction X2 along the middle drying path Pd2.

  At this time, in the second unit 82, the roller 822 that winds the print medium M from the rear surface at the most downstream of the upper drying path Pd1 moves the print medium M that moves horizontally in one direction X1 along the upper drying path Pd1 in the vertical direction. Fold it down parallel to Z. Further, the roller 823 that winds the print medium M from the rear surface at the uppermost stream of the middle drying path Pd2 bends the print medium M that descends in parallel with the vertical direction Z from the roller 822 in the other direction X2 in the horizontal direction X. Thus, the rollers 822 and 823 fold the print medium M from the upper drying path Pd1 to the middle drying path Pd2.

  The first unit 81 has an air turn bar 815 and a roller 816 arranged according to the height of the lower drying path Pd3, and the second unit 82 is arranged according to the height of the lower drying path Pd3. It has a pair of rollers 825, 826. That is, the air turn bar 815 and the rollers 816 of the first unit 81 and the rollers 825 and 826 of the second unit 82 are arranged in this order in one direction X1 to form the lower drying path Pd3, and are folded back from the middle drying path Pd2. The printed printing medium M is horizontally conveyed in one direction X1 along the lower drying path Pd3.

  At this time, in the first unit 81, the air turn bar 814 that winds the printing medium M from the surface at the most downstream of the middle drying path Pd2 moves the printing medium M that moves horizontally in the other direction X2 along the middle drying path Pd2 vertically. Fold it down parallel to direction Z. Further, the air turn bar 815 that winds the print medium M from the surface at the uppermost stream of the lower drying path Pd3 bends the print medium M descending from the air turn bar 814 in the vertical direction Z in one direction X1 in the horizontal direction X. Thus, the air turn bars 814 and 815 fold the print medium M from the middle drying path Pd2 to the lower drying path Pd3. Then, the print medium M is carried out from the lower drying path Pd3 toward the take-up roll 12. Each of the air turn bars 814 and 815 winds around the surface of the print medium M while providing a gap to the surface of the print medium M by jetting air. Thus, the print medium M can be folded back by the air turn bars 814 and 815 while suppressing the influence of the image printed on the surface of the print medium M.

  Further, the second-stage drying unit 8 has second-stage heaters H81 and H82 for drying the ink attached to the surface of the print medium M for each of the upper-stage drying route Pd1, the middle-stage drying route Pd2, and the lower-stage drying route Pd3. That is, in each of the first unit 81 and the second unit 82, the rear heaters H81 and H82 are disposed so as to face the upper drying path Pd1, and the rear heaters H81 and H82 are connected to the printing medium passing through the upper drying path Pd1. Dry the surface of M. In each of the second unit 82 and the first unit 81, the rear heaters H82 and H81 are disposed so as to face the middle drying path Pd2, and the rear heaters H82 and H81 are connected to the printing medium passing through the middle drying path Pd2. Dry the surface of M. Further, in each of the first unit 81 and the second unit 82, the rear heaters H81 and H82 are disposed so as to face the lower drying path Pd3, and the rear heaters H81 and H82 are connected to the printing medium passing through the lower drying path Pd3. Dry the surface of M. The post-stage drying unit 8 dries the ink discharged to the print medium M in the pre-stage printing unit 2 and the post-stage printing unit 6 by the post-stage heaters H81 and H82 arranged as described above.

  As described above, in the printing apparatus 1, the print medium M is folded back by the air turn bars 42, 43, 46, 61, 814, and 815. These air turn bars have a difference in the angle at which the print medium M is wound, but have a basically common configuration. Subsequently, the configuration of these air turn bars will be described. In the following, these air turn bars are collectively referred to as air turn bars 9 without distinction.

  FIG. 6 is a perspective view schematically showing the appearance of the air turn bar, FIG. 7 is a diagram schematically showing the air turn bar developed in the transport direction of the print medium folded by the air turn bar, and FIG. 8 is an air turn bar. FIG. 3 is a diagram schematically illustrating a cross section of a print medium. In these drawings, dimensional relationships are emphasized as appropriate in order to facilitate understanding of the embodiments.

  As shown in FIG. 6, the air turn bar 9 has an arc shape when viewed from the width direction Dw orthogonal to the transport direction Dm, and has a body portion 91 extending in the width direction Dw. The body portion 91 has an outer peripheral surface 92 having a curved surface, and includes a transport surface 93 facing the print medium M transported in the transport direction Dm. Thus, the air turn bar 9 folds the print medium M by winding the print medium M along the transport surface 93 formed of a curved surface.

  As shown in FIGS. 7 and 8, a plurality of holes 94 are opened in the transport surface 93, and a gas such as air or nitrogen is ejected from each hole 94. Therefore, pressure between the print medium M and the transport surface 93 facing the print medium M is increased by the gas ejected from the holes 94. As a result, as shown in FIG. 8, a gap 95 is provided between the print medium M and the transport surface 93 in a normal direction Dn (perpendicular to the transport direction Dm and the width direction Dw) parallel to the normal of the transport surface 93. Is formed. That is, the air turn bar 9 can support the print medium M while the print medium M is floated from the transport surface 93.

  Further, the air turn bar 9 has two outflow suppressing members 96 that are arranged at intervals in the width direction Dw, and these outflow suppressing members 96 are used to control the width of the print medium M conveyed along the conveying surface 93. It is sandwiched from the direction Dw. The outflow suppressing member 96 has an opposing surface 97 having a curved surface along the outer peripheral surface 92 of the body portion 91, and the opposing surface 97 of the outflow suppressing member 96 is positioned outside the body medium 91 in the width direction Dw of the print medium M. It contacts the outer peripheral surface 92. The outflow suppressing member 96 has an inner wall 98 on the side of the print medium M transported along the transport surface 93. The inner wall 98 is erected from the outer peripheral surface 92 in parallel with the normal direction Dn, and faces the end of the print medium M in the width direction Dw. The inner walls 98 of each of the two outflow suppressing members 96 oppose each other in the width direction Dw and sandwich the print medium M from the width direction Dw.

  FIG. 9 is an enlarged view schematically showing the vicinity of the outflow suppressing member of the air turn bar. Since the configurations and functions of the two outflow suppressing members 96 are common, only one outflow suppressing member 96 will be described here. As shown in FIG. 9, the gap 95 between the transport surface 93 and the print medium M has a length Δ95 in the normal direction Dn. In other words, the print medium M facing the transport surface 93 is From the normal direction Dn by a distance Δ95. When the thickness of the gap 95 differs depending on the position in the width direction Dw, the maximum thickness of the gap 95 can be set to the distance Δ95.

  On the other hand, the inner wall 98 of the outflow suppressing member 96 has a length Δ98 in the normal direction Dn. In other words, the inner wall 98 protrudes from the transport surface 93 by the length Δ98 in the normal direction Dn. The length Δ98 of the inner wall 98 is longer than the length Δ95 of the gap 95 between the transport surface 93 and the print medium M (Δ98> Δ95). That is, the inner wall 98 protrudes in the normal direction Dn from the surface Ma (the surface on which an image is printed) of the print medium M.

  The inner wall 98 of the outflow suppressing member 96 and the end of the print medium M facing the transport surface 93 face each other with a gap 99 in the width direction Dw, and the gap 99 has a width Δ99 in the width direction Dw. In other words, the inner wall 98 of the outflow suppressing member 96 and the end of the print medium M are separated from each other at a distance Δ99 in the width direction Dw. The distance Δ99 between the inner wall 98 of the outflow suppressing member 96 and the print medium M is shorter than the length Δ95 of the gap 95 between the transport surface 93 and the print medium M (Δ99 <Δ95).

  In such a configuration, the gas G ejected from the holes 94 opened in the transport surface 93 increases the pressure in the gap 95 between the transport surface 93 and the print medium M, and separates the print medium M from the transport surface 93. Further, a part of the gas G ejected from the hole 94 advances toward the end in the width direction Dw of the print medium M, and flows out of the gap 95 at the end of the print medium M. On the other hand, since the inner wall 98 of the outflow suppressing member 96 faces the gap 95 in the width direction Dw, the gas G flowing out of the gap 95 in the width direction Dw collides with the inner wall 98 of the outflow suppressing member 96. A part of the gas G colliding with the inner wall 98 stays near the inner wall 98, a part is pushed back to the gap 95, and a part is a gap between the inner wall 98 of the outflow suppressing member 96 and the print medium M. It is thought to leak from 99.

  In the embodiment configured as described above, two outflow suppression members 96 that sandwich the print medium M facing the conveyance surface 93 from the width direction Dw are provided, and these outflow suppression members 96 are provided between the conveyance surface 93 and the print medium M. The gas G flowing out in the width direction Dw is received from the gap 95 between the first and second members. As a result, the outflow of the gas G is suppressed by the outflow suppressing member 96, and the pressure at the end of the print medium M is secured. As a result, it is possible to suppress the print medium M from coming into contact with the transport surface 93 due to a pressure drop at the end of the print medium M.

  Further, the inner wall 98 of the outflow suppressing member 96 on the print medium M side in the width direction Dw is longer in the normal direction Dn of the transport surface 93 than the gap 95 between the transport surface 93 and the print medium M. Thus, the outflow of the gas G can be accurately suppressed by the outflow suppressing member 96, and the pressure at the end of the print medium M can be more reliably secured.

  The distance Δ99 between the outflow suppressing member 96 and the print medium M in the width direction Dw is shorter than the length Δ95 of the gap 95 between the transport surface 93 and the print medium M in the normal direction Dn of the transport surface 93. In such a configuration, the outflow suppressing member 96 is arranged close to the print medium M. Therefore, the outflow of the gas G can be accurately suppressed by the outflow suppressing member 96, and the pressure at the end of the print medium M can be more reliably secured.

  The inner wall 98 of the outflow suppressing member 96 on the print medium M side in the width direction Dw is parallel to the normal direction Dn of the transport surface 93. In such a configuration, the outflow of gas from the gap 95 between the transport surface 93 and the print medium M is accurately suppressed by the inner wall 98 of the outflow suppressing member 96, and the pressure at the end of the print medium M can be more reliably secured. it can.

  FIG. 10 is a view schematically showing a first modification of the air turn bar. Here, the description will be made focusing on the differences from the above-described embodiment, and the description of the common points will be given the same reference numerals and will be omitted as appropriate. However, needless to say, the same effect is achieved by providing the same configuration as the above embodiment. This applies to other modified examples described below.

  In the first modification, one of the two outflow suppressing members 96 (the right outflow suppressing member 96 in the example of FIG. 10) is a movable outflow member configured to be movable in the width direction Dw with respect to the body 91. It is a suppression member 96m. Specifically, the movable outflow suppressing member 96m can be configured by attaching the movable outflow suppressing member 96m to the body portion 91 by a rail extending in the width direction Dw or by magnetic force. The movement of the movable outflow suppressing member 96m may be performed manually by an operator, or may be driven by a motor or an actuator.

  In FIG. 10, the column of “maximum width” shows the print medium M having the maximum width among the widths of the print medium M usable in the printing apparatus 1. In this way, as the print medium M has the maximum width in the width direction Dw, the movable outflow suppression member 96m is located at the end of the body portion 91 in the width direction Dw. On the other hand, in the column of “minimum width”, the printing medium M having the minimum width among the widths of the printing medium M usable in the printing apparatus 1 is shown. In this manner, according to the fact that the print medium M has the minimum width in the width direction Dw, the movable outflow suppressing member 96m is closer to the center side than the end of the body portion 91 in the width direction Dw (in other words, the other outflow suppressing members 96m). Side).

  As described above, in the first modified example, in the width direction Dw, by moving the movable outflow suppressing member 96m in accordance with the width of the print medium M, the movable outflow suppressing member 96m is brought close to the end of the print medium M. Can be placed. Therefore, regardless of the width of the print medium M, the outflow of the gas G is appropriately suppressed by the outflow suppressing member 96, and the pressure at the end of the print medium M can be more reliably secured.

  FIG. 11 is a view schematically showing a second modification of the air turn bar. In the second modified example, similarly to the first modified example, one of the two outflow suppressing members 96 is a movable outflow suppressing member 96n configured to be movable in the width direction Dw with respect to the body portion 91. However, in the first modified example, as a result of bringing the movable outflow suppressing member 96n close to the print medium M having the minimum width, the movable outflow suppressing member 96n is located outside the movable outflow suppressing member 96n in the width direction Dw (in other words, on the opposite side of the printing medium M). ) Is opened, and the gas G is ejected from the hole 94. On the other hand, in the second modification, these holes 94 are closed by the movable outflow suppressing member 96n.

  As shown in the column of “maximum width” in FIG. 11, by positioning the movable outflow suppression member 96 n according to the maximum width of the print medium M, the width between the two outflow suppression members 96 in the width direction Dw. Has a range R1, and the print medium M faces the range R1. In the width direction Dw, the plurality of holes 94 exist within the range R1, and do not exist outside the range R1.

  On the other hand, as shown in the column of "minimum width" in FIG. 11, by positioning the movable outflow suppressing member 96n in accordance with the print medium M having the minimum width, the two outflow suppressing members 96 A range R2 (<R1) is interposed therebetween, and the print medium M faces the range R2. This range R2 is included in the range R1. In such a configuration, the movable range of the inner wall 98 of the movable outflow suppressing member 96n is a range R3 excluding the range R2 from the range R1. The movable outflow suppressing member 96n is wider in the width direction Dw than the movable range R3 of the inner wall 98. Therefore, the movable outflow suppressing member 96n positioned according to the print medium M having the minimum width closes all the holes 94 provided outside the range R2 between the two outflow suppressing members 96 in the width direction Dw. . Furthermore, as long as the inner wall 98 of the movable outflow suppressing member 96n is located within the movable range R3, the movable outflow suppressing member 96n closes all these holes 94.

  As described above, in the second modification, the movable outflow suppressing member 96n is configured to close all the holes 94 provided outside the range between the two outflow suppressing members 96 in the width direction Dw. I have. This closes the holes 94 that do not contribute to the floating of the print medium M, and suppresses the occurrence of pressure loss in the gap 95 between the print medium M and the transport surface 93 due to the outflow of gas from the holes 94. can do.

  In the embodiment described above, the printing device 1 corresponds to an example of the “printing device” of the present invention, the first-stage printing unit 2 and the second-stage printing unit 6 correspond to an example of the “printing unit” of the present invention, The part 4 and the latter drying part 8 correspond to an example of the “drying part” of the present invention, the air turn bar 9 corresponds to an example of the “web supporting device” of the present invention, and the body part 91 corresponds to the “body part” of the present invention. The transport surface 93 corresponds to an example of the “transport surface” of the present invention, the hole 94 corresponds to an example of the “hole” of the present invention, and the outflow suppressing member 96 corresponds to the “outflow suppressing member” of the present invention. The movable outflow suppressing members 96m and 96n correspond to an example of the “movable outflow suppressing member” of the present invention, the inner wall 98 corresponds to an example of the “wall” of the present invention, and the gap 95 corresponds to an example. The print medium M corresponds to an example of the “gap” of the present invention, and corresponds to an example of the “web” of the present invention. The direction Dm corresponds to an example of the “transport direction” of the present invention, the width direction Dw corresponds to an example of the “width direction” of the present invention, and the normal direction Dn corresponds to an example of the “normal direction” of the present invention. I do.

  The present invention is not limited to the above-described embodiment, and various changes other than those described above can be made without departing from the gist of the present invention. For example, the magnitude relationship between the dimensions Δ95, Δ98, and Δ99 shown in FIG. 9 is not limited to the above example.

  Further, the size, shape, position, and the like of the outflow suppressing member 96 can be appropriately changed. For example, the inner wall 98 of the outflow suppressing member 96 may be inclined with respect to the normal direction Dn.

  In the first modification or the second modification, both of the two outflow suppressing members 96 may be movable outflow suppressing members 96m and 96n.

  Further, the curved surface shape of the transport surface 93 of the air turn bar 9 is not limited to the above example.

  Further, it is not necessary to configure all the air turn bars provided in the printing apparatus 1 like the air turn bar 9.

  In addition, the arrangement and number of the ejection heads 27 and 69 in each of the printing units 2 and 6 or the color of the ink to be ejected can be appropriately changed.

  Further, in each of the drying units 4 and 8, the specific configuration of turning the print medium M and the number of times the print medium M is turned may be changed.

  Various inks including aqueous and oily inks can be used for printing. Alternatively, UV (Ultraviolet) ink may be used.

  Further, the arrangement and number of the front heaters H4 in the first drying section 4 may be changed as appropriate, and the arrangement and number of the second heaters H81 and H82 in the second drying section 8 may be changed as appropriate.

  INDUSTRIAL APPLICATION This invention is applicable to all the web conveyance techniques.

1. Printing device 2. Pre-stage printing unit (printing unit)
4: Pre-stage drying unit (drying unit)
6: Post-printing section (printing section)
8: Post-stage drying unit (drying unit)
9 ... Air turn bar (web support device)
91 ... body part 93 ... conveyance surface 94 ... hole 95 ... gap 96 ... outflow suppression member 96m ... movable type outflow suppression member 96n ... movable type outflow suppression member 98 ... inner wall (wall)
Dm: transport direction Dn: normal direction Dw: width direction M: print medium (web)

Claims (8)

Having a conveying surface configured with a curved surface, the web is conveyed from the conveying surface by a gas ejected from a plurality of holes opened in the conveying surface with respect to the web conveyed in a predetermined conveying direction along the conveying surface. A body part supporting the web while floating,
It is arranged at intervals in the width direction orthogonal to the conveyance direction, comprising two outflow suppression members sandwiching the web facing the conveyance surface from the width direction,
The web support device receives the gas flowing out in the width direction from a gap between the transport surface and the web.   2. The web support device according to claim 1, wherein a wall of the outflow suppressing member on the web side in the width direction is longer than a gap between the transport surface and the web in a normal direction of the transport surface.   3. The web support device according to claim 1, wherein a distance between the outflow suppressing member and the web in the width direction is shorter than a length of a gap between the transport surface and the web in a normal direction of the transport surface. 4.   4. The web support device according to claim 1, wherein at least one of the two outflow suppressing members is a movable outflow suppressing member movable in the width direction with respect to the body portion. 5.   The web supporting device according to claim 4, wherein the movable outflow suppressing member is configured to close the hole provided outside a range between the two outflow suppressing members in the width direction.   The web support device according to any one of claims 1 to 5, wherein a wall of the outflow suppressing member on the web side in the width direction is parallel to a normal direction of the transport surface. A printing unit that ejects ink to the web,
A drying unit for drying the web from which the ink has been discharged by the printing unit,
And a web support device according to any one of claims 1 to 6,
A printing device that supports the web with the web support device. While floating the web from the transport surface by gas ejected from a plurality of holes opened in the transport surface for the web transported in a predetermined transport direction along a transport surface configured by a curved surface, the web is Supporting,
Arranged at intervals in the width direction orthogonal to the conveyance direction, by two outflow suppression members sandwiching the web facing the conveyance surface from the width direction, from the gap between the conveyance surface and the web Receiving the gas flowing out in the width direction.

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