JP2018192669A - Inkjet type recording device - Google Patents

Abstract

To provide an inkjet type recording device which can inhibit occurrence of damage to a recording medium and inhibit lines and looseness in the recording medium after printing.SOLUTION: A printer includes: a platen 20 in which an upper surface is formed into a flat shape; an upstream side guide 24 which is disposed at the upstream side of the platen 20, includes an upstream side arc part 25 having a cross section formed into an arc shape, and guides a recording medium 5; a downstream side guide 28 which is disposed at the downstream side of the platen 20, includes a downstream side arc part 29 having a cross section formed into an arc shape, and guides the recording medium 5; a supply shaft 42 around which the recording medium 5 is wound; a grid roller which transports the recording medium 5; a take-up shaft 48 which takes up the recording medium 5 after printing; a first heater 61 which heats the platen 20; a second heater 62 which heats the upstream side arc part 25; and a third heater 63 which heats the downstream side arc part 29. A first curvature of the upstream side arc part 25 is smaller than a second curvature of the downstream side arc part 29.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an ink jet recording apparatus.

  2. Description of the Related Art Conventionally, an ink jet recording apparatus that includes an ink head having a plurality of nozzles that eject ink onto a recording medium and a platen on which the recording medium is placed is known. The ink jet recording apparatus performs predetermined printing on a recording medium by an ink jet method. Such an ink jet recording apparatus includes a heater for heating the platen in order to promote drying of the ink ejected onto the recording medium. By heating the platen, the recording medium placed on the platen is also heated, and the ink ejected on the surface of the recording medium can be dried quickly.

  Further, in Patent Document 1, in addition to the heater for heating the platen, it is arranged on the upstream side of the platen, and is arranged on the upstream side of the arcuate cross section, the preheater for heating the upstream guide, and the downstream side of the platen. An ink jet recording apparatus including a downstream guide having a circular cross section and a post heater for heating the downstream guide is disclosed. The preheater can preliminarily apply heat to the recording medium positioned on the upstream guide by heating the upstream guide. Further, the post heater heats the downstream guide to heat the recording medium located on the downstream guide, and finishes drying of the ink ejected on the surface of the recording medium. Here, the upstream guide and the downstream guide described in Patent Document 1 are formed in the same shape from the viewpoints of design, configuration simplification, and component sharing.

JP 2013-184383 A

  By the way, when a long recording medium wound in a roll shape around the supply shaft (for example, a strip-shaped recording medium) is used as the recording medium, the recording medium is unwound from the supply shaft while being unwound from the upstream guide, platen, and downstream guide. And finally, it is wound into a roll shape by a winding shaft.

  Here, as in Patent Document 1, when the upstream guide and the downstream guide have the same shape, the recording medium unwound from the supply shaft is cold and is relatively weak against warping. It is conceivable to set the curvature of the upstream guide and the downstream guide (that is, the degree of curvature of the curved surface) to be relatively small so as to reduce the damage to the recording medium. However, the warp of the recording medium in the downstream guide becomes insufficient, and when the recording medium conveyed from the downstream guide is wound around the winding shaft having a large curvature, the recording medium may be wrinkled or loosened. is there. On the other hand, if the curvature of the upstream guide and the downstream guide is set to be relatively large in order to properly wind the recording medium with the take-up shaft, the recording medium unwound from the supply shaft is heated sufficiently by the upstream guide. Otherwise, the recording medium may be warped and the recording medium may be damaged.

  The present invention has been made in view of the above points, and an object thereof is to suppress the occurrence of damage to the recording medium before printing and to suppress the occurrence of wrinkles and slack in the recording medium after printing. It is an object of the present invention to provide an ink jet recording apparatus that can perform the above process.

  An ink jet recording apparatus according to the present invention includes an ink head that includes a nozzle that ejects ink onto a long recording medium and is movable in a main scanning direction that is a width direction of the recording medium, and is disposed below the ink head. A platen on which the recording medium is placed and having an upper surface formed in a flat shape; and an upstream formed in a cross-sectional arc shape in a sub-scanning direction orthogonal to the main scanning direction. An upstream guide that guides the recording medium, a downstream arc that is disposed downstream of the platen in the sub-scanning direction, and has a circular arc shape in cross section. A downstream guide for guiding, a supply device disposed below the upstream guide and rotatably supporting a supply shaft around which the recording medium is wound, and provided on the platen, A conveying device that conveys the recording medium unwound from the supply shaft in the sub-scanning direction, and a winding shaft that is disposed below the downstream guide and winds up the recording medium after printing is rotatably supported. A winding device, a first heater for heating the platen, a second heater for heating the upstream arc portion of the upstream guide, and a third heater for heating the downstream arc portion of the downstream guide The first curvature, which is a curvature of at least a part of the upstream arc part of the upstream guide when viewed from the main scanning direction, is at least a part of the downstream arc part of the downstream guide. Is set to be smaller than the second curvature which is the curvature of.

  According to the ink jet recording apparatus of the present invention, when viewed from the main scanning direction, the first curvature of the upstream arc portion is set smaller than the second curvature of the downstream arc portion. For this reason, in order to suppress damage due to warp while heating the recording medium by preliminarily applying heat to the recording medium in the cold state, the curvature of at least a part of the upstream arc portion is relatively set. Can be set small. Thereby, it is possible to prevent the recording medium from being damaged due to warpage in the upstream guide. In addition, in order to appropriately wind the recording medium after printing on the winding shaft, the curvature of at least a part of the downstream arc portion can be set relatively large. As a result, it is possible to suppress the occurrence of sufficient warping of the recording medium in the downstream guide, and the occurrence of wrinkles and slack when the recording medium is taken up by the take-up shaft.

  According to the present invention, it is possible to provide an ink jet recording apparatus that can suppress the occurrence of damage to a recording medium before printing and can suppress the occurrence of wrinkles and slack in the recording medium after printing. it can.

1 is a front view of a printer according to an embodiment. It is sectional drawing which follows the II-II line | wire in FIG. It is sectional drawing which shows the platen which concerns on one Embodiment, and its periphery structure. It is sectional drawing which shows the platen which concerns on another one Embodiment, and its periphery structure.

  Hereinafter, an ink jet recording apparatus according to an embodiment will be described with reference to the drawings. The ink jet recording apparatus according to the present embodiment is an ink jet printer (hereinafter referred to as a printer) 10 that performs printing on a long recording medium (for example, a band-shaped recording medium). It should be noted that the embodiments described herein are not intended to limit the present invention. Moreover, the same code | symbol is attached | subjected to the member and site | part which show | plays the same effect | action, and the overlapping description is abbreviate | omitted or simplified suitably.

  FIG. 1 is a front view of a printer 10 according to the present embodiment. 2 is a cross-sectional view taken along line II-II in FIG. The printer 10 is for printing on the recording medium 5.

  In the following description, left, right, top, and bottom mean left, right, top, and bottom, respectively, as viewed from the operator in front of the printer 10. Further, the direction approaching the worker from the printer 10 is defined as the front, and the direction away from the operator is defined as the rear. Reference numerals F, Rr, L, R, U, and D in the drawings represent front, rear, left, right, upper, and lower, respectively. The symbol Y in the drawing represents the main scanning direction. In the present embodiment, the main scanning direction Y is the left-right direction. The main scanning direction Y is the width direction of the recording medium 5. A symbol X in the drawing indicates a sub-scanning direction. The sub-scanning direction X is a direction that intersects the main scanning direction Y (for example, a direction that intersects perpendicularly in plan view). In the present embodiment, the sub-scanning direction X is the front-rear direction. The sub-scanning direction X is the longitudinal direction of the recording medium 5. However, the above direction is merely determined for convenience and should not be interpreted in a limited manner.

  The recording medium 5 of this embodiment is plain paper. The recording medium 5 is not limited to recording paper as long as it has a shape that can be wound around a supply shaft 42 described later and can be wound around a winding shaft 48. In addition to paper such as plain paper and inkjet printing paper, the recording medium 5 may be a sheet or film made of resin such as polyvinyl chloride or polyester, a fabric such as a woven fabric or a non-woven fabric, or other media.

  As shown in FIG. 1, the printer 10 includes a main body 12, a left side cover 13L and a right side cover 13R, a central wall 14, a platen 20 (see FIG. 2), and an upstream guide 24 (see FIG. 2). A downstream guide 28, a grid roller 30 (see FIG. 2), a pinch roller 32 (see FIG. 2), a guide rail 34, a belt 36, a carriage 38 (see FIG. 2), and an ink head 40. A supply shaft 42 and a winding device 44 are provided.

  As shown in FIG. 1, the main body 12 is supported by a stand 15. The main body 12 extends in the main scanning direction Y. The left side cover 13 </ b> L is provided at the left end of the main body 12. The right side cover 13 </ b> R is provided at the right end of the main body 12. The main body 12 is provided with a central wall 14 extending in the vertical direction. The central wall 14 extends in the main scanning direction Y. The central wall 14 connects the left side cover 13L and the right side cover 13R.

  As shown in FIG. 1, the main body 12 is provided with a platen 20 on which the recording medium 5 is placed. The upper surface of the platen 20 is formed flat. The upper surface of the platen 20 is not curved. As shown in FIG. 2, the platen 20 is provided with a cylindrical grid roller 30. The grid roller 30 is embedded in the platen 20 with its upper surface exposed. The grid roller 30 is driven by a feed motor (not shown). The grid roller 30 is an example of a transport device that moves the recording medium 5 unwound from the supply shaft 42 in the sub-scanning direction X. A plurality of pinch rollers 32 are arranged above the grid roller 30. The pinch roller 32 faces the grid roller 30. The pinch roller 32 is configured such that the position in the vertical direction can be set according to the thickness of the recording medium 5. The recording medium 5 is sandwiched between the pinch roller 32 and the grid roller 30. The grid roller 30 and the pinch roller 32 are configured to be able to convey the recording medium 5 in the sub-scanning direction X while holding the recording medium 5.

  As shown in FIG. 1, the guide rail 34 is provided on the central wall 14. The guide rail 34 is disposed above the platen 20. The guide rail 34 is disposed in parallel with the platen 20. The guide rail 34 extends in the main scanning direction Y. As shown in FIG. 2, a carriage 38 is engaged with the guide rail 34.

  As shown in FIG. 1, the belt 36 is disposed in parallel to the wall surface of the central wall 14. The belt 36 extends in the main scanning direction Y. The belt 36 is an endless belt. Pulleys 16 </ b> A and 16 </ b> B are wound around the right end and the left end of the belt 36. One pulley 16A is connected to a carriage motor 17 that drives the pulley 16A. When the carriage motor 17 rotates, the pulley 16A rotates and the belt 36 travels in the main scanning direction Y.

  As shown in FIG. 2, the carriage 38 is fixed to the belt 36. When the belt 36 travels, the carriage 38 moves in the main scanning direction Y along the guide rail 34.

  As shown in FIG. 2, the ink head 40 is disposed above the platen 20. The ink head 40 includes a nozzle (not shown) that ejects ink onto the recording medium 5. The ink head 40 is provided on the carriage 38. When the carriage 38 moves in the main scanning direction Y, the ink head 40 also moves in the main scanning direction Y. The ink head 40 ejects ink toward the recording medium 5 while moving in the main scanning direction Y.

  As shown in FIG. 2, the supply shaft 42 is disposed below the upstream guide 24. The supply shaft 42 is disposed behind the platen 20. The shaft center 42M of the supply shaft 42 is located behind the first end 24A of the upstream guide 24 described later. The shaft center 42M of the supply shaft 42 is located in front of the second end 24B. The axis 42M of the supply shaft 42 is located on the platen 20 side from the second end 24B when viewed from the main scanning direction Y. The supply shaft 42 overlaps the upstream guide 24 in plan view. The supply shaft 42 is formed in a cylindrical shape or a columnar shape extending in the left-right direction. A strip-shaped recording medium 5 before printing is wound around the supply shaft 42 in a roll shape. As shown in FIG. 1, the left end portion of the supply shaft 42 is rotatably supported by the left guide plate 42L. The right end portion of the supply shaft 42 is rotatably supported by the right guide plate 42R. The left guide plate 42L and the right guide plate 42R are provided in the main body 12. The left guide plate 42L and the right guide plate 42R are examples of a supply device. When the grid roller 30 conveys the recording medium 5 forward, the recording medium 5 is unwound from the supply shaft 42 and conveyed toward the platen 20. As shown in FIG. 3, the symbol C <b> 1 indicates the radius of curvature of the supply shaft 42. In the present embodiment, the radius of curvature C1 is 4 cm. Reference numeral C <b> 2 indicates a radius of curvature of the recording medium 5 when the recording medium 5 is wound the longest around the supply shaft 42. In the present embodiment, the radius of curvature C2 is 8 cm. The curvature radius C1 and the curvature radius C2 are not limited to the above values.

  The winding device 44 winds up the printed recording medium 5 in a roll shape. As shown in FIG. 1, the winding device 44 includes a tension bar 46, support arms 47 </ b> L and 47 </ b> R, a winding shaft 48, and a motor 49.

  As shown in FIG. 2, the tension bar 46 applies tension to a portion of the recording medium 5 located between the downstream guide 28 and the take-up shaft 48. Specifically, the tension bar 46 applies tension to the recording medium 5 by pushing the recording medium 5 forward and obliquely downward using its own weight. The tension bar 46 is formed in a cylindrical shape or a columnar shape extending in the left-right direction. The tension bar 46 is disposed in parallel with the take-up shaft 48. The tension bar 46 is disposed below the downstream guide 28. The tension bar 46 is disposed in front of the winding shaft 48. As shown in FIG. 1, the tension bar 46 is swingably supported by the support arms 47L and 47R. The support arm 47L is rotatably provided on the first left side wall 48L provided in the main body portion 12. The support arm 47 </ b> R is rotatably provided on the first right side wall 48 </ b> R provided on the main body 12.

  As shown in FIG. 2, the winding shaft 48 is disposed below the downstream guide 28. The winding shaft 48 is disposed in front of the platen 20. The winding shaft 48 is formed in a cylindrical shape or a columnar shape extending in the left-right direction. The take-up shaft 48 takes up the belt-like recording medium 5 after printing. As shown in FIG. 1, the left end portion of the winding shaft 48 is rotatably supported by a second left side wall 49L disposed on the right side of the first left side wall 48L. The right end portion of the winding shaft 48 is rotatably supported by a second right side wall 49R disposed on the left side of the first right side wall 48R. The second left side wall 49L and the second right side wall 49R are provided in the main body portion 12. As shown in FIG. 3, the symbol D <b> 1 indicates the radius of curvature of the winding shaft 48. In the present embodiment, the radius of curvature D1 is 4 cm. Reference sign D <b> 2 indicates the radius of curvature of the recording medium 5 when the recording medium 5 is wound up the longest on the winding shaft 48. In the present embodiment, the radius of curvature D2 is 8 cm. In this embodiment, the radius of curvature C1 of the supply shaft 42 and the radius of curvature D1 of the winding shaft 48 are the same, but they may be different. The curvature radius D1 and the curvature radius D2 are not limited to the above values.

  As shown in FIG. 1, the motor 49 is connected to the winding shaft 48. The motor 49 rotates the winding shaft 48. The motor 49 is disposed between the first right side wall 48R and the second right side wall 49R.

  As shown in FIG. 2, the upstream guide 24 is disposed upstream of the platen 20 in the sub-scanning direction X. In the present embodiment, the upstream guide 24 is disposed behind the platen 20. The upstream guide 24 includes an upstream arc portion 25 formed in an arc shape in cross section. In the present embodiment, the entire upstream guide 24 is configured by the upstream arc portion 25, but a linear portion extending linearly may be provided on the upstream side or the downstream side of the upstream arc portion 25. The upstream arc portion 25 is curved so as to go downward as the distance from the platen 20 increases. That is, the upstream arc portion 25 is curved so as to go downward as it goes rearward. The upstream guide 24 guides the recording medium 5 unwound from the supply shaft 42 to the platen 20. That is, the recording medium 5 unwound from the supply shaft 42 is conveyed along the upstream guide 24. As shown in FIG. 3, the symbol A <b> 1 indicates the radius of curvature of the upstream arc portion 25. In the present embodiment, the radius of curvature A1 is 21 cm. The radius of curvature A1 is not limited to the above value. The central angle α of the upstream arc portion 25 is not less than 45 degrees and not more than 90 degrees. In the present embodiment, the central angle α is approximately 90 degrees. The central angle α is an angle formed by two radii passing through the first end 24A on the upstream side and the second end 24B on the downstream side of the upstream arc portion 25 when viewed from the main scanning direction Y. As shown in FIG. 4, the upstream arc portion 25 is formed between a plurality of bent portions 25A bent upward (here, toward the recording medium 5) and adjacent bent portions 25A. In the case of having a surface 25B (for example, a flat surface or a curved surface), the radius of curvature of the virtual circle L1 passing through the bent portion 25A when viewed from the main scanning direction Y is the radius of curvature A1 of the upstream arc portion 25. And The virtual circle L1 circumscribes the upstream arc portion 25. At this time, the curvature of the upstream arc portion 25 is the reciprocal of the curvature radius A1 (ie, 1 / A1).

  As shown in FIG. 2, the downstream guide 28 is disposed downstream of the platen 20 in the sub-scanning direction X. In the present embodiment, the downstream guide 28 is disposed in front of the platen 20. The downstream guide 28 includes a downstream arc portion 29 formed in an arc shape in cross section. In the present embodiment, the entire downstream guide 28 is configured by the downstream arc portion 29, but a linear portion extending linearly may be provided on the upstream side or the downstream side of the downstream arc portion 29. The downstream arc portion 29 is curved so as to go downward as the distance from the platen 20 increases. That is, the downstream arc portion 29 is curved so as to go downward as it goes forward. The downstream guide 28 guides the recording medium 5 after printing to the take-up shaft 48 via the tension bar 46. That is, the recording medium 5 after printing is conveyed along the downstream guide 28. As shown in FIG. 3, the symbol B <b> 1 indicates the radius of curvature of the downstream arc portion 29. In the present embodiment, the radius of curvature B1 is 15 cm. The curvature radius B1 is not limited to the above value. The central angle β of the downstream arc portion 29 is not less than 45 degrees and not more than 90 degrees. In the present embodiment, the central angle β is approximately 60 degrees. The central angle β is an angle formed by two radii passing through the first end portion 28A on the upstream side and the second end portion 28B on the downstream side of the downstream arc portion 29 when viewed from the main scanning direction Y. As shown in FIG. 4, the downstream arc portion 29 is formed between a plurality of bent portions 29A bent upward (here, toward the recording medium 5) and the adjacent bent portions 29A. In the case of having a surface 29B (for example, a flat surface or a curved surface), the radius of curvature of the virtual circle L2 passing through the bent portion 29A when viewed from the main scanning direction Y is the radius of curvature B1 of the downstream arc portion 29. And The virtual circle L2 circumscribes the downstream arc portion 29. At this time, the curvature of the downstream-side arc portion 29 is the reciprocal of the curvature radius B1 (ie, 1 / B1).

  FIG. 3 is a cross-sectional view showing the platen 20 and its peripheral structure. In FIG. 3, the grid roller 30 and the pinch roller 32 are not shown for convenience. As shown in FIG. 3, when viewed from the main scanning direction Y, the first curvature M1 of the upstream arc portion 25 of the upstream guide 24 is set smaller than the second curvature M2 of the downstream arc portion 29 of the downstream guide 28. Has been. 2nd curvature M2 / 1st curvature M1 is 1.1-2.0, for example, Preferably, it is 1.3-1.6. In the present embodiment, the second curvature M2 / first curvature M1 is 1.4. The curvature radius A1 of the upstream arc portion 25 is set to be larger than the curvature radius B1 of the downstream arc portion 29, for example. The curvature radius B1 / the curvature radius A1 is, for example, 0.5 to 0.9, and preferably 0.6 to 0.8. In the present embodiment, the radius of curvature B1 / the radius of curvature A1 is approximately 0.7. The central angle α of the upstream arc portion 25 is set to be equal to or larger than the central angle β of the downstream arc portion 29. The length A2 of the upstream arc portion 25 in the sub-scanning direction X is set to be longer than the length B2 of the downstream arc portion 29 in the sub-scanning direction X. When viewed from the main scanning direction Y, the arc length A 3 of the upstream arc portion 25 is set to be longer than the arc length B 3 of the downstream arc portion 29. When viewed from the main scanning direction Y, the first curvature of the upstream arc portion 25 is set to be smaller than the third curvature of the supply shaft 42. That is, the curvature radius A1 of the upstream arc portion 25 is set larger than the curvature radius C1 of the supply shaft 42. When viewed from the main scanning direction Y, the first curvature of the upstream arc portion 25 is set smaller than the fourth curvature of the recording medium 5 when the recording medium 5 is wound the longest around the supply shaft 42. That is, the curvature radius A1 of the upstream arc portion 25 is set larger than the curvature radius C2 of the recording medium when the recording medium 5 is wound the longest around the supply shaft 42. When viewed from the main scanning direction Y, the second curvature of the downstream arc portion 29 is set to be smaller than the fifth curvature of the winding shaft 48. That is, the curvature radius B1 of the downstream arc portion 29 is set to be larger than the curvature radius D1 of the winding shaft 48. When viewed from the main scanning direction Y, the second curvature of the downstream arc portion 29 is smaller than the sixth curvature of the recording medium 5 when the recording medium 5 is wound the longest on the winding shaft 48. That is, the curvature radius B1 of the downstream arc portion 29 is set to be larger than the curvature radius D2 of the recording medium 5 when the recording medium 5 is wound the longest on the winding shaft 48.

  As shown in FIG. 2, the printer 10 includes a first heater 61, a second heater 62, and a third heater 63. The first heater 61 is provided on the platen 20. The first heater 61 is provided below the platen 20. The first heater 61 is disposed in front of the grid roller 30. The first heater 61 heats the platen 20. By heating the platen 20, the recording medium 5 after printing disposed on the platen 20 is heated, and the drying of the ink is promoted.

  The second heater 62 is provided in the upstream guide 24. The second heater 62 is provided below the upstream guide 24. The second heater 62 heats at least the upstream arc portion 25 of the upstream guide 24. In the present embodiment, the second heater 62 heats the entire upstream guide 24. By heating the upstream arc portion 25, preliminary heat is applied to the recording medium 5 guided on the upstream arc portion 25, and the recording medium 5 becomes resistant to warpage. The second heater 62 is disposed along the entire sub-scanning direction X of the upstream guide 24, but may be disposed at a part of the upstream guide 24 in the sub-scanning direction X. For example, the second heater 62 may be disposed along the entire upstream arc portion 25.

  The third heater 63 is provided in the downstream guide 28. The third heater 63 is provided below the downstream guide 28. The third heater 63 heats at least the downstream arc portion 29 of the downstream guide 28. In the present embodiment, the third heater 63 heats the entire downstream guide 28. When the downstream arc portion 29 is heated, the recording medium 5 guided on the downstream arc portion 29 is heated, and the ink of the recording medium 5 after printing is finished to be dried. The third heater 63 is disposed along the entire sub-scanning direction X of the downstream guide 28, but may be disposed at a part of the downstream guide 28 in the sub-scanning direction X. For example, the third heater 63 may be disposed along the entire downstream arc portion 29.

  As described above, according to the printer 10 of the present embodiment, when viewed from the main scanning direction Y, the first curvature of the upstream arc portion 25 is set smaller than the second curvature of the downstream arc portion 29. That is, the curvature radius A1 of the upstream arc portion 25 is set larger than the curvature radius B1 of the downstream arc portion 29. For this reason, in order to suppress damage due to warp while heating the recording medium 5 by the second heater 62 preliminarily applying heat to the cold recording medium 5, at least a part of the upstream arc portion 25. The curvature can be set relatively small. As a result, it is possible to suppress the recording medium 5 from being damaged due to warpage in the upstream guide 24. Further, in order to appropriately wind the recording medium 5 after printing on the winding shaft 48, the curvature of at least a part of the downstream arc portion 29 can be set relatively large. As a result, it is possible to prevent the downstream guide 28 from sufficiently warping the recording medium 5 and causing wrinkles and slacks when the recording medium 5 is taken up by the take-up shaft 48.

  According to the printer 10 of the present embodiment, the length A2 of the upstream arc portion 25 in the sub-scanning direction X is longer than the length B2 of the downstream arc portion 29 in the sub-scanning direction X. Thus, by relatively increasing the first length A2 of the upstream arc portion 25 in the sub-scanning direction X, the time for preheating the recording medium 5 can be lengthened and damage due to warpage can be prevented. Can be suppressed.

  According to the printer 10 of this embodiment, when viewed from the main scanning direction Y, the arc length A3 of the upstream arc portion 25 is longer than the arc length B3 of the downstream arc portion 29. Thus, by relatively increasing the arc length A3 of the upstream arc portion 25, it is possible to lengthen the time for preheating the recording medium 5, and to suppress damage due to warpage. .

  According to the printer 10 of the present embodiment, when viewed from the main scanning direction Y, the first center angle α of the upstream arc portion 25 is not less than 45 degrees and not more than 90 degrees, and the second center angle β of the downstream arc portion 29 is It is 45 degrees or more and 90 degrees or less, and the first central angle α is equal to or larger than the second central angle β. Thereby, the time for preliminarily heating the recording medium 5 can be lengthened, and damage due to warpage can be suppressed. Further, the upstream arc portion 25 and the downstream arc portion 29 can be arranged in a compact manner.

  According to the printer 10 of the present embodiment, when viewed from the main scanning direction Y, the first curvature of the upstream arc portion 25 is smaller than the third curvature of the supply shaft 42. Thereby, in the upstream arc part 25, the damage by the curvature of the recording medium 5 can be reduced.

  According to the printer 10 of the present embodiment, when viewed from the main scanning direction Y, the first curvature of the upstream arc portion 25 is the fourth curvature of the recording medium 5 when the recording medium 5 is wound the longest around the supply shaft 42. Smaller than. Thereby, in the upstream arc part 25, the damage by the curvature of the recording medium 5 can be reduced.

  According to the printer 10 of the present embodiment, when viewed from the main scanning direction Y, the second curvature of the downstream arc portion 29 is smaller than the fifth curvature of the winding shaft 48. Thereby, the recording medium 5 can be wound up compactly on the winding shaft 48.

  According to the printer 10 of the present embodiment, when viewed from the main scanning direction Y, the second curvature of the downstream arc portion 29 is the first curvature of the recording medium 5 when the recording medium 5 is wound the longest on the winding shaft 48. Less than 6 curvatures. Thereby, the recording medium 5 after printing can be more firmly wound around the winding shaft 48.

  According to the printer 10 of the present embodiment, when the first curvature of the upstream arc portion 25 is M1 and the second curvature of the downstream arc portion 29 is M2, M2 / M1 is 1.1 to 2.0. . Thereby, it is possible to effectively realize the damage to the recording medium 5 before printing and the suppression of the occurrence of wrinkles and slack in the recording medium 5 after printing.

  According to the printer 10 of the present embodiment, the first heater 61 is provided on the platen 20, the second heater 62 is provided on the upstream guide 24, and the third heater 63 is provided on the downstream guide 28. . Thereby, each heater 61, 62, 63 can efficiently heat the platen 20, the upstream arc portion 25 of the upstream guide 24, and the downstream arc portion 29 of the downstream guide 28, respectively.

  According to the printer 10 of the present embodiment, when viewed from the main scanning direction Y, the shaft center 42M of the supply shaft 42 is located on the opposite side of the end portion of the upstream arc portion 25 from the first end portion 24A on the platen 20 side. It is located on the platen 20 side from the second end 24B. Thereby, the length of the entire printer 10 in the sub-scanning direction X can be reduced.

  In the embodiment described above, the overall first curvature M1 of the upstream arc portion 25 of the upstream guide 24 is set to be smaller than the overall second curvature M2 of the downstream arc portion 29 of the downstream guide 28. It is not limited to this. For example, when the upstream arc portion 25 of the upstream guide 24 and the downstream arc portion 29 of the downstream guide 28 are each composed of a plurality of arc portions having different curvatures, the upstream arc portion of the upstream guide 24. The curvature of the 25 specific arc portions may be set smaller than the curvature of the specific arc portion of the downstream arc portion 29 of the downstream guide 28.

5 recording medium 10 printer 20 platen 24 upstream guide 25 upstream arc portion 28 downstream guide 29 downstream arc portion 40 ink head 42 supply shaft 48 take-up shaft 61 first heater 62 second heater 63 third heater

Claims (11)

An ink head comprising a nozzle for ejecting ink to a long recording medium, and movable in a main scanning direction which is a width direction of the recording medium;
A platen disposed below the ink head, on which the recording medium is placed, and having a flat upper surface;
An upstream guide that is disposed upstream of the platen in the sub-scanning direction perpendicular to the main scanning direction and includes an upstream arc portion formed in a cross-sectional arc shape, and guides the recording medium;
A downstream guide that is disposed downstream of the platen in the sub-scanning direction and includes a downstream arc portion formed in a cross-sectional arc shape, and guides the recording medium;
A supply device disposed below the upstream guide and rotatably supporting a supply shaft around which the recording medium is wound;
A transport device that is provided on the platen and transports the recording medium unwound from the supply shaft in the sub-scanning direction;
A winding device that is disposed below the downstream guide and rotatably supports a winding shaft that winds up the recording medium after printing;
A first heater for heating the platen;
A second heater for heating the upstream arc portion of the upstream guide;
A third heater that heats the downstream arc portion of the downstream guide,
The first curvature, which is a curvature of at least a part of the upstream arc portion of the upstream guide as viewed from the main scanning direction, is a curvature of at least a part of the downstream arc portion of the downstream guide. An ink jet recording apparatus set to be smaller than two curvatures.   2. The ink jet recording apparatus according to claim 1, wherein a length of the upstream arc portion in the sub scanning direction is longer than a length of the downstream arc portion in the sub scanning direction.   3. The ink jet recording apparatus according to claim 1, wherein an arc length of the upstream arc portion is longer than an arc length of the downstream arc portion when viewed from the main scanning direction.   When viewed from the main scanning direction, the first central angle of the upstream arc portion is not less than 45 degrees and not more than 90 degrees, the second center angle of the downstream arc portion is not less than 45 degrees and not more than 90 degrees, 4. The ink jet recording apparatus according to claim 1, wherein one central angle is equal to or greater than the second central angle. 5.   5. The ink jet recording apparatus according to claim 1, wherein when viewed from the main scanning direction, the first curvature of the upstream arc portion is smaller than a third curvature of the supply shaft.   6. The first curvature of the upstream arc portion when viewed from the main scanning direction is smaller than a fourth curvature of the recording medium when the recording medium is wound the longest around the supply shaft. Inkjet recording apparatus.   7. The ink jet recording apparatus according to claim 1, wherein the second curvature of the downstream arc portion is smaller than a fifth curvature of the winding shaft when viewed from the main scanning direction.   The second curvature of the downstream arc portion when viewed from the main scanning direction is smaller than a sixth curvature of the recording medium when the recording medium is wound on the winding shaft for the longest time. 2. An ink jet recording apparatus according to 1.   Any one of claims 1 to 8, wherein M2 / M1 is 1.1 to 2.0, where M1 is a first curvature of the upstream arc portion and M2 is a second curvature of the downstream arc portion. The ink jet recording apparatus according to one item. The first heater is provided on the platen,
The second heater is provided in the upstream guide,
The ink jet recording apparatus according to claim 1, wherein the third heater is provided in the downstream guide.   When viewed from the main scanning direction, the center of the supply shaft is located closer to the platen than a second end located opposite to the first end on the platen side of the upstream arc portion. An ink jet recording apparatus according to any one of claims 1 to 10.

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