Printing apparatus and printing method

Abstract

The present invention provides a printing apparatus and a printing method. The objective is to properly eliminate curling of a portion of a medium. The printing apparatus (1) includes: a conveying unit (31); a printing unit (20); a winding unit (54) capable of winding a medium; and a curling elimination roller pair (52) capable of performing a curling elimination operation, which involves clamping and bending a curled portion (PA) of the medium that is wound on the winding unit (54) in a corrective direction. The curling elimination operation is performed when the conveying of the medium has stopped for a first predetermined time or more while it is wound on the winding unit (54), and the medium is conveyed until the curled portion (PA) reaches the curling elimination roller pair (52). After the conveying has stopped for a second predetermined time while the curled portion (PA) is clamped by the curling elimination roller pair, the medium is conveyed toward the printing unit (20).

Description

Technical Field

[0001] This invention relates to a printing apparatus and a printing method. Background Technology

[0002] Various printing apparatuses have been used throughout history. Among them are printing apparatuses that transport media and print on the transported media. In such printing apparatuses, the media is sometimes transported in a curled manner along the transport path, resulting in curling on the media. For example, Patent Document 1 describes a situation where, when the power to the printing apparatus is turned off, the portion of the media located at the bend in the transport path has curl marks. Therefore, the printing apparatus of Patent Document 1 includes a heater section located near the discharge port and a curl-removing section located near the inlet of the transport path. In the case of curl marks on the media, in order to remove the curling, the curled portion is brought downstream of the printing section in the transport direction to the heater section, and after being heated by the heater section, the curled portion is transported in the reverse direction until it reaches the curl-removing section. Furthermore, the curl-removing section can use its rollers to hold the curled portion for a predetermined time to remove the curling.

[0003] However, in the printing apparatus of Patent Document 1, it takes time because the portion with curl marks needs to be conveyed to the heater section once and then returned to the curl-removal position. Furthermore, since the creased media must be conveyed to the heater section, the creased portion in the conveying path to the heater section may cause paper jams. Additionally, since the heater section is located near the discharge port, there is a possibility that the user may touch the media ejected from the discharge port, causing poor conveying. Moreover, although the printing apparatus of Patent Document 1 performs a curl-removal sequence whenever power is turned on, if the period from the time the power is turned off to the next time it is turned on is short, sometimes the portion located at the bend may not have very strong curl marks. In such cases, by performing the curl-removal sequence when the power is turned on again, new curl marks that curl in the opposite direction may be generated. Thus, in conventional printing apparatuses, it is difficult to properly remove curl marks generated on the media.

[0004] Patent document 1: Japanese Patent Application Publication No. 2016-135694. Summary of the Invention

[0005] The printing apparatus of the present invention for solving the above-mentioned problems is characterized by comprising: a conveying unit that conveys a medium along a conveying path in a conveying direction; a printing unit that sprays droplets onto the medium to perform printing; a winding unit disposed on the conveying path and capable of winding the medium; a curl-removing roller pair located downstream of the winding unit in the conveying direction and capable of performing a curl-removing operation, the curl-removing operation being an operation of clamping and bending the curled portions on the medium caused by being wound on the winding unit in a corrective direction; and a control unit, wherein... Control is performed in a manner that enables the curl elimination operation to be executed, and the transport of the medium carried out by the transport unit is controlled. The curl elimination operation is an operation performed when the transport has stopped for more than a first predetermined time while the medium is wound on the winding unit. The control unit performs the following process: the medium is transported until the curled portion reaches the curl elimination roller pair, and after the transport is stopped for a second predetermined time while the curled portion is clamped by the curl elimination roller pair, the medium is transported toward the printing unit.

[0006] Furthermore, the printing method of the present invention for solving the above-mentioned problems is characterized in that it is a printing method performed by a printing apparatus comprising: a conveying unit that conveys a medium along a conveying path in a conveying direction; a printing unit that sprays droplets onto the medium to perform printing; a winding unit disposed on the conveying path and capable of winding the medium; and a curl-removing roller pair located downstream of the winding unit in the conveying direction and capable of performing a curl-removing operation, the curl-removing operation being an operation of clamping and bending a curled portion on the medium that is generated due to being wound on the winding unit in the medium in the printing method, wherein the curl-removing operation is performed when the conveying has stopped for a first predetermined time or more while the medium is wound on the winding unit, the medium is conveyed until the curled portion reaches the curl-removing roller pair, and after the conveying has stopped for a second predetermined time while the curled portion is clamped by the curl-removing roller pair, the medium is conveyed toward the printing unit. Attached Figure Description

[0007] Figure 1 This is a side sectional view illustrating the internal structure of a printing apparatus according to an embodiment of the present invention.

[0008] Figure 2 To indicate Figure 1 The diagram shows a side cross-sectional view of the printing apparatus's winding section and the periphery of the curl-removing roller pair, illustrating the mechanism by which curled portions are generated on the medium.

[0009] Figure 3 To indicate Figure 1 The diagram shows a side cross-sectional view of the printing apparatus's winding section and the periphery of the curl-removing roller pair, illustrating the mechanism of correcting and eliminating curled portions generated on the medium.

[0010] Figure 4 To indicate by Figure 1 A flowchart of an example of a printing method implemented by a printing apparatus. Detailed Implementation

[0011] First, the present invention will be described in a general sense.

[0012] The printing apparatus of the first aspect of the present invention for solving the above-mentioned problems is characterized by comprising: a conveying unit that conveys a medium along a conveying path in a conveying direction; a printing unit that sprays droplets onto the medium to perform printing; a winding unit disposed on the conveying path and capable of winding the medium; and a curl-removing roller pair located downstream of the winding unit in the conveying direction and capable of performing a curl-removing operation, the curl-removing operation being an operation of clamping and bending curled portions on the medium caused by being wound on the winding unit in a corrective direction; and control. The control unit controls the delivery of the medium by the conveying unit in a manner that enables the curl elimination operation to be performed. The curl elimination operation is an operation performed when the delivery has stopped for more than a first predetermined time while the medium is wound on the winding unit. The control unit performs the following process: the medium is conveyed until the curled portion reaches the curl elimination roller pair, and after the delivery is stopped for a second predetermined time while the curled portion is clamped by the curl elimination roller pair, the medium is conveyed toward the printing unit.

[0013] According to this method, the curl elimination operation is performed after the media has been stopped for a first predetermined time or more while it is being wound on the winding section. The media is then conveyed until the curled portion reaches the curl elimination roller pair. After the conveying is stopped for a second predetermined time while the curled portion is clamped by the curl elimination roller pair, the media is conveyed toward the printing section. By performing this curl elimination operation, the amount of media conveyed during the curl elimination operation can be reduced, allowing the curl elimination operation to be performed in a short time. Furthermore, by appropriately setting the first and second predetermined times, it is possible to correct the curl marks while suppressing new curling marks in the reverse direction on the curled portion. In other words, curling marks generated on the media can be appropriately eliminated.

[0014] The printing apparatus of the second aspect of the present invention is characterized in that, in a aspect subordinate to the first aspect, the control unit performs the following processing: whenever the transport of the medium stops, it counts the elapsed time from the stop of the transport of the medium; if the transport of the medium is performed after the elapsed time has passed the first predetermined time, it performs the curl elimination operation during the transport performed after the first predetermined time has passed; and if the transport of the medium is performed before the elapsed time has passed the first predetermined time, it does not perform the curl elimination operation during the transport, and resets the elapsed time.

[0015] According to this method, whenever the medium transport stops, the elapsed time is counted. If the medium transport is carried out after the elapsed time has exceeded a first predetermined time, a curling elimination action is performed. If the medium transport is carried out before the elapsed time has exceeded the first predetermined time, the curling elimination action is not performed, and the elapsed time is reset. By performing such a curling elimination action, it is possible to appropriately correct the curling marks while suppressing new curling marks in the opposite direction on the curled portion.

[0016] The third-party printing apparatus of the present invention is characterized in that, in a mode subordinate to the first mode or the second mode, the first predetermined time and the second predetermined time can be varied according to at least one of the rigidity and thickness of the medium.

[0017] According to this method, the first predetermined time and the second predetermined time can be varied based on at least one of the rigidity and thickness of the medium. By performing such a curl-removal operation, the curled portions generated on the medium can be removed in a particularly appropriate manner based on at least one of the rigidity or thickness of the medium.

[0018] The printing apparatus of the fourth aspect of the present invention is characterized in that, in any of the aspects belonging to the first to the third aspects, the first predetermined time and the second predetermined time can be changed according to at least one of the ambient temperature and the ambient humidity.

[0019] According to this method, the first predetermined time and the second predetermined time can be changed based on at least one of the ambient temperature and ambient humidity. By performing such a curling elimination action, the curling portions generated on the medium can be eliminated in a particularly appropriate manner based on at least one of the ambient temperature or ambient humidity.

[0020] The printing apparatus of the fifth aspect of the present invention is characterized in that, in any of the aspects belonging to the first to the fourth aspects, the second predetermined time is shorter than the first predetermined time.

[0021] According to this method, the second predetermined time is shorter than the first predetermined time. By performing such a curl removal action, the time spent on curl removal can be shortened, and the curl marks can be appropriately corrected while suppressing new curl marks that curl in the opposite direction on the curled portion.

[0022] The printing apparatus of the sixth aspect of the present invention is characterized in that, in any of the first to fifth aspects, the second predetermined time can be varied according to the time when the conveying stops while the medium is wound on the winding section.

[0023] According to this method, the second predetermined time can be changed based on the time during which the conveying process stops while the medium is wound on the winding section. By performing such a curl-eliminating operation, it is possible to appropriately correct the curl marks while suppressing new curl marks that curl in the opposite direction on the curled portion.

[0024] The printing apparatus of the seventh aspect of the present invention is characterized in that, in any of the first to sixth aspects, when the control unit conveys the medium until the curled portion reaches the curl-eliminating roller pair, while the curl-eliminating roller pair is clamping the medium, it conveys a predetermined amount in the conveying direction to allow the curled portion to pass through the curl-eliminating roller pair, and then conveys the medium in the opposite direction to the conveying direction, i.e., the reverse conveying direction, until it reaches the position where the curled portion is clamped by the curl-eliminating roller pair. The curled portion is positioned such that it is clamped by the curl-eliminating roller pair.

[0025] According to this method, while conveying the medium until the curled portion reaches the curl-eliminating roller pair, a predetermined amount is conveyed in the conveying direction by passing the curled portion through the curl-eliminating roller pair while the medium is being held by the curl-eliminating roller pair. The medium is then conveyed in the opposite direction (reverse conveying direction) until it reaches the position where the curled portion is held by the curl-eliminating roller pair, and the curled portion is positioned in a state where it is held by the curl-eliminating roller pair. That is, by passing the curled portion through the curl-eliminating roller pair once, the curling marks are mitigated. Therefore, the second predetermined time can be shortened.

[0026] The printing method of the eighth aspect of the present invention is characterized in that it is a printing method performed by a printing apparatus comprising: a conveying unit that conveys a medium along a conveying path in a conveying direction; a printing unit that sprays droplets onto the medium to perform printing; a winding unit disposed on the conveying path and capable of winding the medium; and a curl-removing roller pair located downstream of the winding unit in the conveying direction and capable of performing a curl-removing operation, the curl-removing operation being an operation of clamping and bending a curled portion on the medium caused by being wound on the winding unit in a corrective direction, the curl-removing operation being performed when the conveying of the medium has stopped for a first predetermined time or more while it is wound on the winding unit, in the printing method, the medium is conveyed until the curled portion reaches the curl-removing roller pair, and after the conveying has stopped for a second predetermined time while the curled portion is clamped by the curl-removing roller pair, the medium is conveyed toward the printing unit.

[0027] According to this method, the curl elimination operation is performed after the media has been stopped for a first predetermined time or more while it is being wound on the winding section. The media is then conveyed until the curled portion reaches the curl elimination roller pair. After the conveying is stopped for a second predetermined time while the curled portion is clamped by the curl elimination roller pair, the media is conveyed toward the printing section. By performing this curl elimination operation, the amount of media conveyed during the curl elimination operation can be reduced, allowing the curl elimination operation to be performed in a short time. Furthermore, by appropriately setting the first and second predetermined times, it is possible to correct the curl marks while suppressing new curling marks in the reverse direction on the curled portion. In other words, curling marks generated on the media can be appropriately eliminated.

[0028] The printing method of the ninth aspect of the present invention is characterized in that, in the aspect subordinate to the eighth aspect, whenever the transport of the medium stops, the elapsed time from the stop of the transport of the medium is counted; if the transport of the medium is performed after the elapsed time has passed the first predetermined time, the curl elimination operation is performed during the transport performed after the first predetermined time has passed; and if the transport of the medium is performed before the elapsed time has passed the first predetermined time, the curl elimination operation is not performed during the transport, and the elapsed time is reset.

[0029] According to this method, whenever the medium transport stops, the elapsed time is counted. If the medium transport is performed after the elapsed time has exceeded a first predetermined time, a curling elimination action is performed. If the medium transport is performed before the elapsed time has exceeded the first predetermined time, the curling elimination action is not performed, and the elapsed time is reset. By performing such a curling elimination action, it is possible to appropriately correct the curling marks while suppressing new curling marks in the opposite direction on the curled portion.

[0030] The printing method of the tenth aspect of the present invention is characterized in that, in the aspect subordinate to the eighth or ninth aspect, the first predetermined time and the second predetermined time can be varied according to at least one of the rigidity and thickness of the medium.

[0031] According to this method, the first predetermined time and the second predetermined time can be varied based on at least one of the rigidity and thickness of the medium. By performing such a curl-removal operation, the curled portions generated on the medium can be removed in a particularly appropriate manner based on at least one of the rigidity or thickness of the medium.

[0032] The printing method of the eleventh aspect of the present invention is characterized in that, in any of the eighth to tenth aspects, the first predetermined time and the second predetermined time can be changed according to at least one of the ambient temperature and the ambient humidity.

[0033] According to this method, the first predetermined time and the second predetermined time can be changed based on at least one of the ambient temperature and ambient humidity. By performing such a curling elimination action, the curling portions generated on the medium can be eliminated in a particularly appropriate manner based on at least one of the ambient temperature or ambient humidity.

[0034] The printing method of the twelfth aspect of the present invention is characterized in that, in any of the aspects belonging to the eighth to eleventh aspects, the second predetermined time is shorter than the first predetermined time.

[0035] According to this method, the second predetermined time is shorter than the first predetermined time. By performing such a curl-eliminating action, it is possible to appropriately correct the curl marks while suppressing new curl marks that curl in the opposite direction on the curled portion.

[0036] The printing method of the thirteenth aspect of the present invention is characterized in that, in any of the eighth to twelfth aspects, the second predetermined time can be changed according to the time when the conveying stops while the medium is wound on the winding section.

[0037] According to this method, the second predetermined time can be changed based on the time during which the conveying process stops while the medium is wound on the winding section. By performing such a curl-eliminating operation, it is possible to appropriately correct the curl marks while suppressing new curl marks that curl in the opposite direction on the curled portion.

[0038] The printing method of the fourteenth aspect of the present invention is characterized in that, in any of the eighth to thirteenth aspects, while the medium is being conveyed until the curled portion reaches the curl-eliminating roller pair, in a state where the curl-eliminating roller pair clamps the medium, the curled portion is conveyed in the conveying direction in a manner that allows it to pass through the curl-eliminating roller pair, and the medium is conveyed in the opposite direction to the conveying direction, i.e., the reverse conveying direction, until the curled portion is clamped by the curl-eliminating roller pair, and the curled portion is set to a state where it is clamped by the curl-eliminating roller pair.

[0039] According to this method, while the medium is being conveyed until the curled portion reaches the curl-eliminating roller pair, a predetermined amount of the curled portion is conveyed in the conveying direction by passing through the curl-eliminating roller pair while the medium is being held by the curl-eliminating roller pair. The medium is then conveyed in the opposite direction (reverse conveying direction) until it reaches the position where the curled portion is held by the curl-eliminating roller pair, and the curled portion is positioned in a state where it is held by the curl-eliminating roller pair. That is, by passing the curled portion through the curl-eliminating roller pair once, the curling marks are mitigated. Therefore, the second predetermined time can be shortened.

[0040] Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings. First, referring to... Figure 1 The outline of a printing apparatus 1 according to one embodiment of the present invention will be described below. The printing apparatus 1 is, for example, an inkjet printer that ejects ink onto a medium for printing. In the coordinate system shown in the drawings, the printing apparatus 1 is assumed to be placed on a horizontal plane, and three mutually orthogonal imaginary axes are designated as the X-axis, Y-axis, and Z-axis. The Y-axis is an axis parallel to the front-back direction of the printing apparatus 1, and the front end of the arrow representing the Y-axis is designated as "front". The X-axis is an axis parallel to the left-right direction of the printing apparatus 1, and the front end of the arrow representing the X-axis is designated as "right". The Z-axis is an imaginary axis parallel to the vertical direction, and the front end of the arrow representing the Z-axis is designated as "up".

[0041] like Figure 1As shown, the printing apparatus 1 includes a housing 2. Inside the housing 2 are provided: a roll paper storage section 40, which stores roll paper RP as a medium; a sheet paper storage section 60, which stores sheet paper SP, a medium other than roll paper RP; and a printing section 20, which can print on roll paper RP supplied from the roll paper storage section 40 and on sheet paper SP supplied from the sheet paper storage section 60.

[0042] The printing unit 20 includes: a head 22 having a nozzle that ejects ink toward a medium; and a carriage 21 mounting the head 22. Furthermore, the printing unit 20 is configured to allow the carriage 21 to reciprocate along the X-axis. A support portion 25 is provided opposite the head 22 to support the medium. The head 22 ejects ink while reciprocating in the width direction B together with the carriage 21, thereby printing on the medium supported on the support portion 25. Although this embodiment exemplifies a serial head configuration where the head 22 reciprocates in the width direction, a row head configuration where the heads are arranged in a width direction is also possible.

[0043] Inside the housing 2, there is a transport path 30 for transporting the medium and a cutting section 27 for cutting the medium printed by the printing section 20. The transport path 30 has a supply path 30a and a turning path 30b located upstream of the support section 25, and a discharge path 30c located downstream of the support section 25. Furthermore, the supply path 30a has a roll paper supply path 30R for supplying a roll of paper RP as an example of the medium, and a sheet paper supply path 30S for supplying a single sheet of paper SP as an example of the medium.

[0044] The supply path 30a is a path that connects to the support section 25 from the roll paper supply path 30R. Upstream of the supply path 30a, there is a roll paper confluence point P2 that merges with the roll paper supply path 30R. Downstream of the supply path 30a, there is a branch point P1 that branches off from the supply path 30a when the medium is transported from downstream to upstream. The reversing path 30b is a path that connects to the roll paper confluence point P2 from the branch point P1. Between the roll paper confluence point P2 and the branch point P1 in the supply path 30a, there is a sheet paper confluence point P3 that merges with the sheet paper supply path 30S.

[0045] A discharge port 14 for discharging the printed medium is provided on the front surface of the housing 2. The discharge path 30c is a path that connects from the support portion 25 to the discharge port 14. A cutting portion 27 is provided in the middle of the discharge path 30c to cut off the medium printed by the printing portion 20.

[0046] A conveying section 31 is provided on the conveying path 30 to convey the medium supplied to the conveying path 30. The conveying section 31, from upstream to downstream, includes an intermediate roller 32, a plurality of driven rollers 33 disposed on the outer periphery of the intermediate roller 32, and an upstream conveying roller pair 34. The driven rollers 33 are rotatably disposed and rotate drivenly while sandwiching the medium between themselves and the intermediate roller 32. The conveying section 31, from upstream to downstream, includes a downstream conveying roller pair 35, a roller pair 36, and a roller pair 37 on the discharge path 30c. The roller pair 36 is located upstream of the cutting section 27, and the roller pair 37 is located downstream of the cutting section 27.

[0047] The intermediate roller 32, driven roller 33, upstream conveying roller pair 34, downstream conveying roller pair 35, roller pair 36, and roller pair 37 convey the medium by rotating while the medium is being held between them. By driving the conveying unit 31 to rotate forward, the medium is conveyed in the conveying direction A, i.e., from upstream to downstream. By driving the conveying unit 31 to rotate in reverse, the medium is conveyed in the opposite direction to the conveying direction A, i.e., from downstream to upstream.

[0048] The printing apparatus 1, while driving the conveyor section 31 in a forward direction to transport the medium from upstream to downstream, sprays ink from the printing section 20 onto the medium located on the support section 25 to print on the first surface of the medium. The printing apparatus 1 is configured to print on the back side, i.e., the second surface, of the medium. The printing apparatus 1, by driving the conveyor section 31 in a reverse direction, transports the medium, after printing on the first surface, in the opposite direction. The medium arrives upstream of the supply path 30a from the branch point P1 via the reversing path 30b. The printing apparatus 1, again driving the conveyor section 31 in a forward direction, causes the medium to rotate once on the outer circumference of the intermediate roller 32, thereby reversing the surface of the medium. The printing apparatus 1, while transporting the medium from upstream to downstream, sprays ink from the printing section 20 onto the medium located on the support section 25 to print on the second surface of the medium. Thus, printing is performed on both sides of the medium. In addition, in the case of a roll of paper RP unrolled from a roll state, printing is performed on the back side of the medium after printing on the surface and cutting it into individual sheets by the cutting section 27.

[0049] Furthermore, a roll paper storage section 40 is provided inside the housing 2. The roll paper storage section 40 includes a first medium holding section 42 that holds the roll paper RP in its roll state, and the roll paper RP is rotatably supported via a support shaft 41 extending in the X direction of the housing 2. That is, the roll paper RP is supported by the roll paper storage section 40 together with the support shaft 41, allowing it to rotate with the support shaft 41 as the rotation center. The support shaft 41 is configured to rotate in both the forward and reverse directions. In the roll paper storage section 40, a roll paper transport path 50 is provided at a position opposite to the support member 43 for transporting the roll paper RP unrolled from its roll state. The roll paper transport path 50 constitutes a roll paper supply path 30R.

[0050] The roll paper transport path 50 includes a first roll pair 51, a second roll pair 52, a third roll pair 53, and a curved surface 54. The first roll pair 51 has a drive roll 51a driven by a motor and a driven roll 51b opposite to the drive roll 51a and rotating passively in sync with the drive roll 51a. The second roll pair 52 has a drive roll 52a driven by a motor and a driven roll 52b opposite to the drive roll 52a and rotating passively in sync with the drive roll 52a. The third roll pair 53 has a drive roll 53a driven by a motor and a driven roll 53b opposite to the drive roll 53a and rotating passively in sync with the drive roll 53a. The curved surface 54 has a curved surface 54a for sliding of the transported medium. In the roll paper conveying path 50, the medium is conveyed in the conveying direction A, i.e., from upstream to downstream, by driving the first roller pair 51, the second roller pair 52 and the third roller pair 53 to rotate forward while being pressed against the curved surface 54a of the curved section 54.

[0051] A sheet-fed storage section 60 is provided inside the housing 2. The sheet-fed storage section 60 has a box-shaped tray 61 for storing sheet-fed media SP. The tray 61 has a pair of edge guides 65 that are operated when positioning the sheet-fed SP in the width direction, a stop 64 that is operated when positioning the sheet-fed SP in the front-back direction, and a mounting surface 63 that faces the downstream end of the sheet-fed SP stored in the tray 61 against the pickup roller 72.

[0052] The sheet-fed storage section 60 constitutes part of the sheet-fed supply unit 70 that supplies sheet-fed paper SPs toward the printing section 20. The sheet-fed supply unit 70 includes the sheet-fed storage section 60, the sheet-fed transport path 71, the pick-up roller 72, the damping roller 73, the separation roller 74, the separation component 76, etc. The sheet-fed storage section 60 has a mounting surface 63 that serves as a mounting section capable of loading multiple sheet-fed paper SPs. The pick-up roller 72 is positioned opposite the sheet-fed storage section 60 and transports the sheet-fed paper SPs placed in the sheet-fed storage section 60 in the transport direction A from the sheet-fed storage section 60 toward the printing section 20.

[0053] The sheet-fed transport path 71 curves upward from the separating roller 74 and the damping roller 73, thus forming the sheet-fed supply path 30S. Sheet-fed transport roller pairs 75, which impart transport force to individual sheets SP, are appropriately spaced along the sheet-fed transport path 71. The individual sheets SP are transported by rotating the sheet-fed transport roller pairs 75.

[0054] As described above, the printing apparatus 1 of this embodiment includes: a conveying unit 31 that conveys a medium in the conveying direction A along the conveying path 30; and a printing unit 20 that sprays droplets onto the medium conveyed in the conveying path 30 to perform printing. Furthermore, the roll paper supply path 30R includes a curved surface 54 having a curved surface 54a, a first roller pair 51, a second roller pair 52, and a third roller pair 53.

[0055] Here, the second roller pair 52 conveys the medium in the conveying path 30 while pressing it against the curved surface 54a of the curved section 54. If the conveying is continuously stopped while the medium is pressed against the curved surface 54a, curling (curling marks) may occur that bulges downward along the curved surface 54a. Therefore, the second roller pair 52 is structured such that it can convey the medium while it is curled upward in the opposite direction to the curved surface 54a.

[0056] If other descriptions are used, the printing apparatus 1 of this embodiment includes: a curved section 54, which is disposed on the transport path 30 and serves as a winding section capable of winding up the medium; and a second roller pair 52, which is located downstream of the curved section 54 in the transport direction A and serves as a take-up eliminating roller pair capable of performing a curl-eliminating operation, which is an operation of clamping and bending the curled portion on the medium caused by being wound on the curved section 54 in a corrective direction. Furthermore, as... Figure 1 As shown, the printing apparatus 1 of this embodiment includes a control unit 80, which can control the second roller pair 52 to perform a curl-removal operation and can control the transport of the medium carried out by the transport unit 31.

[0057] In the following text, with reference Figure 2 as well as Figure 3 Simultaneous use Figure 4 The following describes in detail the curl elimination operation, which is an example of a printing method implemented using the printing apparatus 1 of this embodiment. The curl elimination operation implemented using the printing apparatus 1 of this embodiment is implemented by controlling each component of the printing apparatus 1 of this embodiment by the control unit 80, and is implemented when the transport of the medium has stopped for more than a first predetermined time while it is being wound on the curved surface 54a of the curved section 54.

[0058] In the curl elimination operation performed using the printing apparatus 1 of this embodiment, in step S110, the control unit 80 counts the elapsed time since the last media delivery operation. Then, when the control unit 80 receives an instruction command from the user, such as an instruction for printing operation accompanied by media delivery, in step S120, it determines in step S130 whether the elapsed time counted in step S110 has elapsed for a first predetermined time (e.g., 8 hours). If the control unit 80 determines in step S130 that the elapsed time has elapsed for the first predetermined time, it proceeds to step S140; if the control unit 80 determines in step S130 that the elapsed time has not elapsed for the first predetermined time, it proceeds to step S150.

[0059] When proceeding from step S130 to step S140, a predetermined amount of medium is conveyed in step S140, and in the subsequent step S160, the conveying is stopped for a second predetermined time (e.g., 20 seconds) and maintained in this state. Specifically, if the elapsed time counted in step S110 is longer than the first predetermined time before executing step S140, etc. Figure 2 As shown by the dashed lines, sometimes due to being wound on the curved surface 54, a curl (crease) that bulges downward along the curved surface 54a may occur in the area PA of the medium (roll paper RP). Therefore, in step S140, a predetermined amount of medium is conveyed, such as... Figure 3 As shown, region PA is conveyed to the clamping position held by the second roller pair 52. Then, in step S160, this state is maintained for a second predetermined time.

[0060] At the clamping position held by the second roller pair 52, such as Figure 3As shown, region PA is maintained in an upwardly convex state by being wound onto the driven roller 52b of the second roller pair 52. By performing such an operation in steps S140 and S160, curling that occurs when region PA convexes downward due to being wound onto the curved surface 54 can be eliminated (curling removal). Then, after performing step S160, according to the user's instruction command such as the printing operation instruction in step S120, which accompanies the delivery of the medium, the medium is delivered in step S170, and the curling removal operation performed using the printing apparatus 1 of this embodiment ends.

[0061] On the other hand, if the process proceeds from step S130 to step S150, the time will be reset and the process will proceed to step S170. Then, in accordance with the instructions from the user, such as the printing operation instructions in step S120, which are accompanied by media delivery, the media will be delivered in step S170, and the curl elimination operation performed using the printing apparatus 1 of this embodiment will be terminated.

[0062] As mentioned above, when using Figure 4 In the curl elimination operation performed by the printing apparatus 1 of this embodiment, under the control of the control unit 80, the medium is conveyed in step S140 until the curled portion (area PA) reaches the second roller pair 52, which serves as the curl elimination roller pair. Then, in step S160, the conveying is stopped for a second predetermined time while the curled portion (area PA) is clamped by the second roller pair 52. Then, in step S170, the medium is conveyed toward the printing unit 20.

[0063] By performing this curl-removal action, the amount of medium transported during the curl-removal action can be reduced, thereby enabling the curl-removal action to be performed in a short time. Furthermore, by appropriately setting the first and second predetermined times, it is possible to correct curl marks while suppressing new curl marks in the curled portion (region PA) that curl in the opposite direction. In other words, curl marks generated in the medium can be appropriately removed.

[0064] Furthermore, by performing such curl elimination, the risks of paper jams and media damage that may occur during transport in the transport path 30 can be reduced. In addition, the time spent on curl elimination can be shortened, thereby reducing the time spent until printing. Furthermore, it can prevent the leading edge of the media from being ejected outside the housing 2, thus preventing the user from touching the media ejected outside the housing 2. Moreover, by physically bending the media in the opposite direction to where the curl marks were generated, the improvement effect of curl elimination can be enhanced.

[0065] In addition, in use Figure 4 In the curl elimination operation performed by the printing apparatus 1 of this embodiment, the control unit 80 controls the counting of elapsed time from the stop of media delivery in step S110 whenever media delivery stops. Then, in step S130, if the control unit 80 determines that media delivery has been performed after a first predetermined time has elapsed, the curl elimination operation is performed in steps S140 and S160 when delivery is performed after the first predetermined time has elapsed, corresponding to step S140. On the other hand, if the control unit 80 determines in step S130 that media delivery has been performed before the first predetermined time has elapsed, the curl elimination operation for delivery corresponding to steps S140 and S160 is not performed, and the elapsed time is reset in step S150. By performing such a curl elimination operation, it is possible to suppress new curling marks in the opposite direction on the curled portion (region PA) while appropriately correcting the curling marks.

[0066] In this embodiment of the printing apparatus 1, the control unit 80 can receive input from the user regarding information such as the type of medium used via a computer (not shown). Furthermore, the printing apparatus 1 of this embodiment can, based on information such as the medium used, change the first predetermined time in step S130 and the second predetermined time in step S160 according to at least one of the rigidity and thickness of the medium.

[0067] By performing such a curl-removal action, the curled portion (region PA) generated in the medium can be removed in a particularly appropriate manner depending on at least one of the rigidity and thickness of the medium. Specifically, when the thickness of the medium increases and the rigidity becomes higher, at least one of shortening the first predetermined time and extending the second predetermined time can be used; and when the thickness of the medium decreases and the rigidity decreases, at least one of extending the first predetermined time and shortening the second predetermined time can be used.

[0068] Furthermore, the printing apparatus 1 of this embodiment includes a thermometer and a hygrometer (not shown), and the control unit 80 can receive information about the ambient temperature and humidity measured by the thermometer and hygrometer. Moreover, the printing apparatus 1 of this embodiment can change the first predetermined time and the second predetermined time based on at least one of the ambient temperature and ambient humidity. Alternatively, instead of installing a thermometer and hygrometer, the control unit 80 can receive input of information such as ambient temperature and humidity from the user via a computer (not shown).

[0069] By performing such a curling elimination action, the curled portion (region PA) generated on the medium can be eliminated in a particularly appropriate manner depending on at least one of the ambient temperature and ambient humidity. Specifically, since the medium tends to harden when the ambient temperature and ambient humidity are low, at least one of shortening the first predetermined time and extending the second predetermined time can be used; and since the medium tends to soften when the ambient temperature and ambient humidity are high, at least one of extending the first predetermined time and shortening the second predetermined time can be used.

[0070] Here, as described above, for example, the second predetermined time can be set to 20 seconds, and the first predetermined time can be set to 8 hours. Thus, it is preferable that the second predetermined time is shorter than the first predetermined time. This is because by performing such a curl removal operation, the time spent on curl removal can be shortened, and the curl marks can be appropriately corrected while suppressing new curl marks that curl in the opposite direction on the curled portion (region PA).

[0071] However, the printing apparatus 1 of this embodiment can change the second predetermined time based on the time when the medium stops being transported while it is being wound on the curved surface 54, which serves as the winding section. By making it possible to change the time when the medium stops being transported while it is being wound on the curved surface 54, it is possible to properly correct the creases while suppressing new creases that curl in the opposite direction on the curled portion (area PA).

[0072] Furthermore, the printing apparatus 1 of this embodiment, when controlling the medium to be conveyed in step S140 until the curled portion (area PA) reaches the second roller pair 52 through the control unit 80, can perform the following operations: Initially, with the medium clamped by the second roller pair 52, a predetermined amount is conveyed in the conveying direction A such that the curled portion (area PA) passes through the second roller pair 52. Next, the medium is conveyed in the opposite direction to the conveying direction A, i.e., the reverse conveying direction, until the curled portion (area PA) is clamped by the second roller pair 52. Finally, the curled portion (area PA) is set to a state where it is clamped by the second roller pair 52.

[0073] That is, in this embodiment, the printing apparatus 1 softens the curling marks by passing the curled portion (area PA) once through the second roller pair 52, which serves as a curl-removing roller pair, and then removes the curling marks by clamping them again by the second roller pair 52. By performing this operation, the second predetermined time can be shortened. Here, the predetermined amount is the amount that only requires the entire curled portion (area PA) to pass through the second roller pair 52, which serves as a curl-removing roller pair, and it is preferably not too long.

[0074] This invention is not limited to the embodiments described above, but can be implemented with various structures without departing from its spirit. Furthermore, in order to solve some or all of the above-described problems, or to achieve some or all of the above-described effects, the technical features in the embodiments corresponding to the technical features in the various methods described in the summary section can be appropriately replaced or combined. In addition, any technical feature that is not described as an essential technical feature in this specification can be appropriately deleted.

[0075] Symbol Explanation 1…printing apparatus; 2…housing; 14…outlet; 20…printing section; 21…carriage; 22…head; 25…support section; 27…cutting section; 30…conveyor path; 30a…supply path; 30b…turning path; 30c…discharge path; 30R…roll paper supply path; 30S…sheet paper supply path; 31…conveyor section; 32…intermediate roller; 33…driven roller; 34…upstream conveyor roller pair; 35…downstream conveyor roller pair; 36…roll pair; 37…roll pair; 40…roll paper receiving section; 41…support shaft; 42…first media holding section; 43…support member; 50…roll paper conveying path; 51…first roller pair; 51a…drive roller; 51b…driven roller; 5 2…Second roller pair (curl-removing roller pair); 52a…Drive roller; 52b…Driven roller; 53…Third roller pair; 53a…Drive roller; 53b…Driven roller; 54…Curved section (winding section); 54a…Curved surface; 60…Sheet storage section; 61…Tray; 63…Placement surface; 64…Stop; 65…Edge guide; 70…Sheet supply unit; 71…Sheet transport path; 72…Pick-up roller; 73…Damping roller; 74…Separation roller; 75…Sheet transport roller pair; 76…Separation component; 80…Control section; P1…Branch point; P2…Roll confluence point; P3…Sheet confluence point; PA…Area (curl section); RP…Roll; SP…Sheet.

Claims

1. A printing apparatus, characterized in that, have: The conveying unit transports the medium along the conveying path in the conveying direction; A printing section that sprays droplets onto the medium to perform printing; A winding section is provided on the conveying path and is capable of winding the medium; A curl-eliminating roller pair is located downstream of the winding portion in the conveying direction and is capable of performing a curl-eliminating action, which is an action of clamping and bending the curled portion that is generated on the medium due to being wound on the winding portion in the corrective direction. The control unit controls the operation in a manner capable of performing the curl-eliminating action and also controls the transport of the medium carried out by the transport unit. The curl elimination action is performed when the medium has stopped transporting for more than a first predetermined time while it is being wound on the winding part. The control unit performs the following processing: The medium is conveyed until the curled portion reaches the curl-removing roller pair, and After the conveying is stopped for a second predetermined time while the curled portion is clamped using the curl-eliminating roller pair, the medium is conveyed toward the printing section.

2. The printing apparatus as claimed in claim 1, characterized in that, The control unit performs the following processing: Whenever the delivery of the medium stops, the elapsed time since the delivery of the medium stops is counted. If the medium is conveyed after the first predetermined time has elapsed, the curling elimination action is performed during the conveying operation after the first predetermined time has elapsed. If the medium is conveyed before the elapsed time has elapsed to the first predetermined time, the curling elimination action is not performed during the conveying, and the elapsed time is reset.

3. The printing apparatus as claimed in claim 1, characterized in that, The first predetermined time and the second predetermined time can be changed according to at least one of the rigidity and thickness of the medium.

4. The printing apparatus as claimed in claim 1, characterized in that, The first predetermined time and the second predetermined time can be changed according to at least one of the ambient temperature and ambient humidity.

5. The printing apparatus as claimed in claim 1, characterized in that, The second scheduled time is shorter than the first scheduled time.

6. The printing apparatus as claimed in claim 1, characterized in that, The second predetermined time can be changed according to the time when the conveying stops while the medium is wound on the winding section.

7. The printing apparatus according to any one of claims 1 to 6, characterized in that, The control unit, when conveying the medium until the curled portion reaches the curl-eliminating roller pair, With the medium held in place by the curl-eliminating roller pair, a predetermined amount is conveyed in the conveying direction in such a way that the curled portion passes through the curl-eliminating roller pair. The medium is conveyed in the opposite direction to the conveying direction, i.e., in the reverse conveying direction, until it reaches the position where the curled portion is clamped by the curl-eliminating roller pair, and The curled portion is positioned such that it is clamped by the curl-eliminating roller pair.

8. A printing method, characterized in that, It is a printing method performed by a printing apparatus, the printing apparatus comprising: The conveying unit transports the medium along the conveying path in the conveying direction; A printing section that sprays droplets onto the medium to perform printing; A winding section is provided on the conveying path and is capable of winding the medium; A curl-removing roller pair is located downstream of the winding section in the conveying direction and is capable of performing a curl-removing action, which is an action of clamping and bending the curled portion on the medium caused by being wound on the winding section in a corrective direction. The curl elimination action is performed when the medium has stopped transporting for more than a first predetermined time while it is being wound on the winding part. In the printing method, The medium is conveyed until the curled portion reaches the curl-removing roller pair, and After the second predetermined time of conveying is stopped while the curled portion is clamped using the curl-eliminating roller pair, the medium is conveyed toward the printing section.

9. The printing method as described in claim 8, characterized in that, Whenever the delivery of the medium stops, the elapsed time since the delivery of the medium stops is counted. If the medium is conveyed after the first predetermined time has elapsed, the curling elimination action is performed during the conveying operation after the first predetermined time has elapsed. If the medium is conveyed before the elapsed time has elapsed to the first predetermined time, the curling elimination action is not performed during the conveying, and the elapsed time is reset.

10. The printing method as described in claim 8, characterized in that, The first predetermined time and the second predetermined time can be changed according to at least one of the rigidity and thickness of the medium.

11. The printing method as described in claim 8, characterized in that, The first predetermined time and the second predetermined time can be changed according to at least one of the ambient temperature and ambient humidity.

12. The printing method as described in claim 8, characterized in that, The second scheduled time is shorter than the first scheduled time.

13. The printing method as described in claim 8, characterized in that, The second predetermined time can be changed according to the time when the conveying stops while the medium is wound on the winding section.

14. The printing method according to any one of claims 8 to 13, characterized in that, While the medium is being conveyed until the curled portion reaches the curl-removing roller pair, With the medium held in place by the curl-eliminating roller pair, a predetermined amount is conveyed in the conveying direction so that the curled portion passes through the curl-eliminating roller pair. The medium is conveyed in the opposite direction to the conveying direction, i.e., in the reverse conveying direction, until it reaches the position where the curled portion is clamped by the curl-eliminating roller pair, and The curled portion is positioned such that it is clamped by the curl-eliminating roller pair.

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