JP7243773B2 - Intermediate unit, post-processing device and printing device - Google Patents

Description

The present invention relates to an intermediate unit, a post-processing device, and a printing device.

2. Description of the Related Art Conventionally, as a device for printing an image on paper, for example, an inkjet printer having a recording head that ejects liquid ink in the form of droplets is known.
By the way, when an image is printed using an inkjet printer, the paper on which the image is printed may curl (a state in which a part of the paper is bent or deformed) due to absorption of ink (moisture) or drying of the ink. There is
Therefore, Japanese Patent Application Laid-Open No. 2002-200000 discloses an inkjet printer that can prevent curling by providing a drying device that dries the paper by applying hot air to the surface of the paper on which an image is printed.

JP 2012-139820 A

However, with the inkjet printer in Patent Document 1, there is no problem in the case of single-sided printing, but in the case of paper on which images are printed on both sides, drying of the ink on the side that does not face the drying device is insufficient, and curling cannot be sufficiently suppressed. There was a fear that
For this reason, when the sheets of paper on which images are printed by the inkjet printer are successively placed on the processing tray, there is a problem that stacking defects occur due to curling.

The present invention has been made to solve or improve the problems described above, and can be implemented as the following forms or application examples.

Application Example 1 An intermediate unit according to this application example has a transport path capable of transporting a medium printed by a printing unit that prints on a medium with a liquid to a post-processing unit that performs post-processing on the medium. A drying unit for promoting drying of the medium is provided on the transport path.

According to this application example, since the drying unit that accelerates the drying of the medium is provided in the transport path, the medium can be sufficiently dried by the drying unit during transport, thereby suppressing the occurrence of curling. It is possible to provide an intermediate unit capable of Therefore, when post-processing the media discharged from the intermediate unit, it is possible to reduce the occurrence of stacking defects due to curling, and it is also possible to reduce misalignment caused by the high frictional resistance of the printed media. can.

APPLICATION EXAMPLE 2 In the intermediate unit according to the application example described above, it is preferable that the conveying path is provided with a reversing path for reversing the front and back of the medium.

According to this application example, since the reversing path is provided in the transportation path, the medium can be turned upside down during transportation.

Application Example 3 In the intermediate unit according to the application example described above, it is preferable that the drying unit is provided in the reversing path.

According to this application example, since the drying unit is provided in the reversing path, it is possible to secure a long area in which the medium is straightened when drying the medium. Therefore, the size of the intermediate unit can be reduced.

Application Example 4 In the intermediate unit according to the above application example, it is preferable that the intermediate unit has a plurality of the reversing paths, and the drying unit is provided in a specific reversing path among the plurality of reversing paths.

According to this application example, since the drying unit is provided in the specific reversing path among the plurality of reversing paths, it is possible to reduce the size and power consumption of the intermediate unit.

Application Example 5 In the intermediate unit according to the application example described above, it is preferable that one of the plurality of reversing paths is selected according to print data of the medium.

According to this application example, it is possible to efficiently reverse the medium by selecting one of the plurality of reverse paths according to the print data of the medium.

[Application Example 6] In the intermediate unit according to the application example described above, it is determined whether or not the difference in water content between the front and back surfaces of the medium is equal to or greater than a predetermined threshold value, based on the print data. It is preferred to drive the drying unit.

According to this application example, if the difference in moisture content between the front and back sides of the medium based on the print data is equal to or greater than the predetermined threshold value, the drying unit can be driven to dry the medium, thereby suppressing the occurrence of curling. Also, the frictional resistance of the medium due to the water content of the liquid can be reduced.

[Application Example 7] In the intermediate unit according to the application example described above, the medium having a moisture content equal to or greater than a predetermined threshold according to the moisture content of the front and back surfaces of the medium based on the print data is conveyed through the specific reverse path, and the printing is performed. Preferably, said media with data less than a predetermined threshold are carried down one said reversing path of said plurality of reversing paths other than said particular reversing path.

According to this application example, it is possible to dry the medium by conveying the medium having a predetermined threshold value or more according to the water content on the front and back sides of the medium based on the print data to the specific reversing path provided with the drying unit. Therefore, the occurrence of curling can be suppressed, and the frictional resistance of the medium due to the water content of the liquid can be reduced.

Application Example 8 In the intermediate unit according to the above application example, the drying units include a first drying unit facing one surface of the medium, a second drying unit facing the other surface of the medium, is preferably included.

According to this application example, by providing the first drying unit facing one surface of the medium and the second drying unit facing the other surface of the medium, both surfaces of the medium can be dried simultaneously. Therefore, drying can be promoted more.

Application Example 9 In the intermediate unit according to the application example described above, it is preferable that driving of the first drying unit and the driving of the second drying unit are controlled independently according to the print data.

According to this application example, by independently controlling the driving of the first drying unit and the second drying unit according to the print data, the drying conditions of the one side and the other side of the medium can be changed. By maintaining a balance, deformation of the medium due to secondary curling or the like can be suppressed.

Application Example 10 In the intermediate unit according to the above application examples, it is preferable that the drying unit includes a blower.

According to this application example, when the medium is dried, it is dried by blowing air from the air blower, so deformation such as curling of the medium due to the air pressure of the blowing air can be easily suppressed. Also, since no heat source is used, the power consumption of the intermediate unit can be reduced.

[Application Example 11] In the intermediate unit according to the application example described above, the reversing path provided with the blower is configured by a switchback system, and the reversing path has a direction in which the medium enters the reversing path. A holding unit that holds the medium that has entered the reversing path is provided downstream of the blower, and the holding unit is located further from the leading end side of the medium in the direction in which the medium enters the reversing path. It is preferable to hold the medium at a portion near the rear end side of the .

According to this application example, by holding the medium in a portion near the rear end of the medium in the holding section on the downstream side of the blower, the air can be blown onto the medium, and the area in which the medium is straightened can be elongated. be able to. Therefore, the medium can be dried in a straight state, and deformation such as curling of the medium can be easily suppressed.

[Application Example 12] In the intermediate unit according to the application example described above, in the reversing path, with respect to the medium for which drying by the drying unit is omitted, the medium is moved from the drying unit in the direction in which the medium enters the reversing path. is preferably switched back on the upstream side.

According to this application example, it is possible to shorten the conveying distance and the conveying time by switching back the medium for which drying is omitted on the upstream side of the drying unit, so that the reversing process can be performed at high speed.

Application Example 13 In the intermediate unit according to the application example described above, it is preferable that the transport path is provided with a tension applying mechanism that applies tension to the medium along the transport path.

According to this application example, since the tension applying mechanism that applies tension to the medium is provided in the transport path of the intermediate unit, the shape of the medium can be held flat and corrected by the tension applying mechanism during transport. Therefore, it is possible to provide an intermediate unit that can suppress curling of the medium. Therefore, when the media discharged from the intermediate unit are post-processed, it is possible to reduce the occurrence of stacking defects due to deformation such as curling of the printed media.

Application Example 14 A post-processing apparatus according to this application example is a post-processing apparatus that performs post-processing on a medium printed by a printing unit that prints on the medium with liquid. A processing section and a transport path that can transport the medium to the post-processing section are provided, and the transport path is provided with a drying unit that promotes drying of the medium.

According to this application example, since the printed medium can be sufficiently dried by the drying unit provided in the transport path, curling can be suppressed, and the frictional resistance of the medium due to the water content of the liquid can be reduced. can be reduced. Therefore, it is possible to provide a post-processing apparatus that reduces stacking defects due to curling of printed media and misalignment due to high frictional resistance when performing post-processing on media.

Application Example 15 In the post-processing apparatus according to the application example described above, it is preferable that the conveying path is provided with a reversing path for reversing the front and back of the medium.

According to this application example, since the reversing path is provided in the transportation path, the medium can be turned upside down during transportation.

APPLICATION EXAMPLE 16 A printing apparatus according to this application example includes a printing unit that performs printing on a medium with a liquid, a post-processing unit that performs post-processing on the medium printed by the printing unit, and a printing unit that prints the medium. a transport path capable of transporting the medium from the medium to the post-processing section, the transport path including a reversing path for reversing the front and back of the medium, and the transport path provided with a drying unit for promoting drying of the medium. It is characterized by being

According to this application example, since the printed medium can be sufficiently dried by the drying unit provided in the transport path, curling can be suppressed, and the frictional resistance of the medium due to the water content of the liquid can be reduced. can be reduced. Therefore, it is possible to provide a printing apparatus that reduces the occurrence of stacking defects due to curling of printed media and misalignment due to high frictional resistance when the media are post-processed.

1 is a schematic diagram showing the configuration of a printing apparatus; FIG. FIG. 2 is a configuration diagram showing the configuration of a printing unit; FIG. 4 is a configuration diagram showing the configuration of an intermediate unit; 4A and 4B are schematic diagrams showing an operation method of the printing apparatus; 4A and 4B are schematic diagrams showing an operation method of the printing apparatus; 4A and 4B are schematic diagrams showing an operation method of the printing apparatus; 4A and 4B are schematic diagrams showing an operation method of the printing apparatus; 4A and 4B are schematic diagrams for explaining the operation of the drying unit of the intermediate unit according to the first embodiment; FIG. The block diagram which shows another structure of the drying unit provided in the intermediate|middle unit. FIG. 11 is an enlarged perspective view of the periphery of the second reversing path in another configuration of the drying unit provided in the intermediate unit; The figure which looked at FIG. 10 from another angle. FIG. 11 is a cross-sectional view along line JJ of the second inversion path shown in FIG. 10; FIG. 11 is a cross-sectional view along line KK of the second inversion path shown in FIG. 10; 4 is a flow chart showing an operation method of the printing apparatus having the intermediate unit according to the first embodiment; FIG. 9 is a schematic diagram for explaining the operation of the tension applying mechanism of the intermediate unit according to the second embodiment; 10 is a flow chart showing an operating method of a printing apparatus having an intermediate unit according to the second embodiment; FIG. 9 is a schematic diagram for explaining the operation of the tension applying mechanism of the intermediate unit according to the modified example of the second embodiment; 9A and 9B are schematic diagrams for explaining the operation of the liquid ejection unit of the intermediate unit according to the third embodiment; 10 is a flow chart showing an operation method of a printing apparatus having an intermediate unit according to the third embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following figures, the scale of each member and the like is changed from the actual scale in order to make the size of each member and the like recognizable.

(First embodiment)
<Configuration of printing device>
First, the configuration of the printing apparatus will be described. FIG. 1 is a schematic diagram showing the configuration of a printing apparatus, FIG. 2 is a configuration diagram showing the configuration of a printing unit, and FIG. 3 is a configuration diagram showing the configuration of an intermediate unit. As shown in FIG. 1, the printing apparatus 1 according to this embodiment includes a printing unit 100 as a printing section and a post-processing device 2 arranged on the side of the printing unit 100 . Further, the post-processing device 2 includes an intermediate unit 200 and a post-processing unit 300 as a post-processing section. The printing unit 100 is, for example, a device that prints an image on paper M as a medium. The printing unit 100 also includes a control section 10 that controls driving of each mechanism in the printing apparatus 1 in an integrated manner. The post-processing unit 300 is, for example, a device that performs post-processing such as stapler processing for binding a plurality of sheets of paper M on which images have been printed. The intermediate unit 200 is a device that conveys the paper M on which an image has been printed by the printing unit 100 to the post-processing unit 300 . The intermediate unit 200 is arranged between the printing unit 100 and the post-processing unit 300 .

In the printing apparatus 1 of this embodiment, the third discharge path 153 as the upstream transport path of the printing unit 100 is connected to the transport path 218 at the inlet 210 of the intermediate unit 200 , and the transport path 218 is used for transporting the intermediate unit 200 . It is connected to the downstream transport path 319 of the post-processing unit 300 at the outlet 211 . Then, through the upstream transport path (third discharge path 153), the transport path 218, and the downstream transport path 319, from the printing unit 100, which is upstream in the transport direction of the paper M, via the intermediate unit 200, It constitutes a transport path (a chain double-dashed line in FIG. 1) continuing to the post-processing unit 300 .

<Configuration of printing unit>
As shown in FIG. 1, the printing unit 100 is an inkjet printer that records images such as characters, figures, and photographs by attaching ink, which is an example of a liquid, to paper M, which is an example of a medium. , the recording apparatus side housing 101 of the. An operation unit 102 for performing various operations of the printing unit 100 is attached to the upper portion of the recording apparatus side housing 101 .

A paper cassette 103 is provided in the printing unit 100 from the center to the bottom of the printing unit 100 in the vertical direction Z. As shown in FIG. In this embodiment, four paper cassettes 103 are arranged side by side in the vertical direction Z. As shown in FIG. Each paper cassette 103 accommodates sheets of paper M to be printed by the printing unit 100 in a stacked state. Further, each paper cassette 103 is formed with a grip portion 103a that can be gripped by the user. The paper cassette 103 is configured to be detachable from the housing 101 on the recording apparatus side. Note that the sheets M accommodated in the respective sheet cassettes 103 may be of different types, or may be of the same type.

A rectangular front plate cover 104 is provided above the uppermost paper cassette 103 in the vertical direction Z. As shown in FIG. The front plate cover 104 is rotatably provided with a long side adjacent to the paper cassette 103 as a base end. It is configured to be rotatable between two positions, a closed position forming part of 101 .

Further, as shown in FIG. 2, a discharge port 108 through which the paper M is discharged is formed in a part of the recording apparatus housing 101 on the intermediate unit 200 side. Further, below the discharge port 108, a paper discharge tray 109 extending from the recording apparatus housing 101 toward the intermediate unit 200 is provided so as to be attachable as required. That is, the paper M ejected through the ejection port 108 is placed on the paper ejection tray 109 . Note that the discharge tray 109 is detachable from the recording apparatus housing 101, and has a base end connected to the recording apparatus housing 101 toward a tip opposite to the base end. It has an upward slope (rising to the left in FIG. 2).

As shown in FIG. 2, in the recording apparatus housing 101 of the printing unit 100, there are a recording unit 110 for recording the paper M from above in the vertical direction Z, and a paper M transport path 120 in the apparatus. A transport unit 130 is provided for transporting along. The intra-apparatus transport path 120 is formed such that when the width direction of the paper M is the direction along the front-rear direction Y, the paper M is transported with the direction intersecting the width direction as the transport direction.

The recording unit 110 includes a line head type recording head 111 capable of simultaneously ejecting ink over substantially the entire width of the paper M. As shown in FIG. The recording unit 110 prints an image on the paper M by applying ink ejected from the recording head 111 to a recording surface of the paper M facing the recording head 111 (a surface on which an image is printed).

The transport unit 130 is arranged along the intra-apparatus transport path 120 and has a plurality of transport roller pairs 131 driven by a transport drive motor (not shown) and a belt transport unit 132 provided immediately below the recording unit 110 . are doing. That is, ink is ejected from the recording head 111 onto the paper M being conveyed by the belt conveying unit 132, and recording is performed.

The belt conveying unit 132 includes a drive roller 133 arranged upstream of the recording head 111 in the conveying direction, a driven roller 134 arranged downstream of the recording head 111 in the conveying direction, these rollers 133, 134 and an endless annular belt 135 . As the drive roller 133 is driven to rotate, the belt 135 rotates, and the sheet M is conveyed downstream by the belt 135 that rotates. That is, the outer peripheral surface of the belt 135 functions as a support surface that supports the paper M on which recording is performed.

The intra-apparatus transport path 120 includes a supply path 140 for transporting the paper M toward the recording unit 110, a discharge path 150 for transporting the paper M that has been recorded by the recording unit 110, and a discharge path. and a branch path 160 branching off from the path 150 .

The supply route 140 has a first supply route 141 , a second supply route 142 and a third supply route 143 . In the first supply path 141 , a sheet M inserted from an insertion opening 141 b exposed by opening a cover 141 a provided on the right side surface of the recording apparatus housing 101 is conveyed to the recording section 110 . That is, the sheet M inserted from the insertion port 141b is linearly transported toward the recording section 110 by the rotational driving of the first drive roller pair 144. As shown in FIG.

In the second supply path 142, in the vertical direction Z, the paper sheets M contained in the paper cassettes 103 provided in the lower part of the recording apparatus side housing 101 are conveyed to the recording section 110. FIG. That is, of the paper sheets M stored in the paper cassette 103 in a stacked state, the uppermost paper sheet M is sent out by the pickup roller 142a and separated sheet by sheet by the pair of separation rollers 145, after which the posture in the vertical direction Z is reversed. While being rotated, the second drive roller pair 146 is driven to rotate and conveyed toward the recording unit 110 .

In the third supply path 143 , when performing double-sided printing in which images are recorded on both sides of the paper M, the paper M whose one side has been recorded by the recording unit 110 is conveyed to the recording unit 110 again. That is, a branch path 160 branching from the discharge path 150 is provided downstream of the recording unit 110 in the transport direction. That is, when double-sided printing is performed, the paper M is conveyed to the branch path 160 by the operation of the branch mechanism 147 provided in the middle of the ejection path 150 . In addition, a pair of branch path rollers 161 capable of rotating in both forward and reverse directions is provided downstream of the branch mechanism 147 in the branch path 160 .

In double-sided printing, the paper M printed on one side is once guided to the branch path 160 by the branch mechanism 147 and conveyed downstream in the branch path 160 by the pair of branch path rollers 161 rotating normally. After that, the sheet M conveyed to the branch path 160 is reversely conveyed in the branch path 160 from the downstream side to the upstream side by the branch path roller pair 161 that reverses. That is, the conveying direction of the sheet M conveyed along the branch path 160 is reversed.

The paper M reversely conveyed from the branch path 160 is conveyed to the third supply path 143 and conveyed toward the recording section 110 by the plurality of conveying roller pairs 131 . By being conveyed through the third supply path 143 , the paper M is reversed so that the other side that is not printed faces the recording section 110 , and is conveyed toward the recording section 110 by rotational driving of the third drive roller pair 148 . be done. In other words, the third supply path 143 functions as a reversing transport path that transports the sheet M while reversing the orientation of the sheet M in the vertical direction Z. As shown in FIG.

Of the supply paths 141 , 142 , and 143 , the second supply path 142 and the third supply path 143 transport the paper M toward the recording unit 110 while the posture of the paper M is curved in the vertical direction Z. On the other hand, in the first supply path 141, the paper M is conveyed toward the recording unit 110 without the posture of the paper M being greatly curved compared to the second supply path 142 and the third supply path 143. .

The paper M conveyed through each of the supply paths 141, 142, and 143 is conveyed to the alignment roller pair 149 arranged on the upstream side in the transportation direction of the recording unit 110, and then to the alignment roller pair 149 whose rotation has stopped. Its tip hits. The inclination of the sheet M with respect to the conveying direction is corrected (skewed) by the state in which the sheet M collides against the pair of alignment rollers 149 . Then, the skew-corrected sheet M is transported to the recording unit 110 in an aligned state by the subsequent rotational driving of the alignment roller pair 149 .

The recording unit 110 performs recording on one side or both sides of the sheet M, and the recording sheet M is transported by the transport roller pair 131 along the discharge path 150 forming the downstream part of the intra-apparatus transport path 120 . The discharge route 150 branches into a first discharge route 151 , a second discharge route 152 , and a third discharge route 153 at positions downstream of the branching route 160 . That is, after the sheet M on which recording has been completed is conveyed through a common discharge route (upstream discharge route) 154 constituting the upstream portion of the discharge route 150, a guide mechanism (switching mechanism) provided at the downstream end of the common discharge route 154 Guide portion 180 guides to one of first to third discharge paths 151 , 152 , and 153 constituting the downstream portion of discharge path 150 .

A first ejection path (upper ejection path) 151 is provided so as to curve upward along the branch path 160 and extend upward from the recording apparatus side housing 101 . The paper M conveyed through the first discharge path 151 is discharged from a discharge port 155 that opens in a part of the recording apparatus side housing 101 so as to be the terminal end of the first discharge path 151 . Then, the paper M discharged from the discharge port 155 falls downward in the vertical direction Z, and is discharged onto the mounting table 156 in a stacked state as indicated by the two-dot chain line in FIG. The sheet M is discharged from the discharge port 155 onto the mounting table 156 by the transport roller pairs 131 arranged at a plurality of positions on the discharge path 150 in such a manner that the recording surface faces downward in the vertical direction Z during single-sided printing. be.

The mounting table 156 has an inclined shape rising upward in the vertical direction Z as it goes rightward in the left-right direction X, and the sheets M are mounted on this mounting table 156 in a stacked state. At this time, each sheet M placed on the mounting table 156 moves to the left along the inclination of the mounting table 156, and moves toward the vertical side wall 157 provided below the discharge port 155 of the recording apparatus side housing 101. is placed close to the

The first ejection path 151 also has a curved reversing path 151 a for reversing the front and back of the paper M recorded by the recording unit 110 while the paper M is conveyed to the ejection port 155 . That is, the curved reversal path 151a is curved with the recording surface of the sheet M recorded by the recording unit 110 facing inward, and the state in which the recording surface of the sheet M faces upward in the vertical direction Z to the vertical direction Z. The sheet M is turned over so that it faces downward. Accordingly, in the ejection path 150, the sheet M is ejected from the ejection port 155 in a state in which the recording surface faces the mounting table 156 during single-sided printing by passing through the curved reversal path 151a.

The second ejection path 152 branches downward in the vertical direction Z from the first ejection path 151 and extends linearly (horizontally) from the recording section 110 toward the intermediate unit 200 . Therefore, the sheet M conveyed through the second ejection path 152 is not conveyed in a curved posture as in the first ejection path 151, but is kept in the same posture as when it passed through the recording unit 110. It is conveyed linearly and discharged from the discharge port 108 toward the paper discharge tray 109 . That is, the second ejection path 152 functions as a non-reversing ejection path that conveys the sheet M toward the ejection tray 109 without reversing the orientation of the sheet M. FIG.

The third discharge path 153 branches downward in the vertical direction Z from the second discharge path 152 and extends obliquely downward in the vertical direction Z so as to go downward from the recording apparatus housing 101 . Its downstream end is connected to the transport path 218 of the intermediate unit 200 . That is, the paper M transported through the third ejection path 153 is ejected to the intermediate unit 200 . A transport detection unit 199 capable of detecting the presence or absence of the paper M is provided in the third discharge path 153 . The transport detection unit 199 is, for example, a light transmission type or light reflection type photointerrupter, and includes a light emitting unit that emits light and a light receiving unit that receives the light emitted from the light emitting unit. As the light emitting element of the light emitting section, for example, an LED (Light Emitting Diode) light emitting element, a laser light emitting element, or the like is applied. Also, the light-receiving portion is configured by a phototransistor, a photo IC, or the like. The presence or absence of the sheet M (ON/OFF of light reception in the light receiving section) can be detected by the light emitting section and the light receiving section.

The transport detection unit 199 is connected to the control unit 10 and driven and controlled based on a predetermined program. The control unit 10 drives the transport detection unit 199 to detect the presence or absence of the paper M by comparing the amount of light received by the light receiving unit with a predetermined threshold value. When the presence and absence of the paper M are repeatedly detected in synchronization with the driving of the transport roller pair 131, it is determined that the paper M is transported normally. On the other hand, if the amount of light received by the light-receiving unit remains unchanged at a predetermined timing or within a predetermined period of time, it is determined that there is an abnormal state (jam). For example, when the paper M is not normally conveyed from the recording head 111 side due to the occurrence of a paper M conveyance failure, it is determined that an abnormal state (jam) has occurred.

A part of the ejection path 150 and a part of the branch path 160 are attached to a drawer unit 170 provided in the recording apparatus side housing 101 . It should be noted that the drawer unit 170 is configured to be detachable from the recording apparatus housing 101 .

Here, the paper M that can be applied to the printing apparatus 1 is preferably hygroscopic and flexible. Ink jet paper having a water-soluble ink absorbing layer containing PVP) or the like. Art paper, coated paper, cast paper, etc., which are used in general offset printing, are examples of absorbent recording media of a type in which water-soluble ink permeates at a relatively low rate.

In the present embodiment, “paper M” generally refers to paper made mainly of pulp (mainly cellulose) and used for printers and the like, and is defined in JIS-P-0001 No. 6139. Specifically, for example, high-quality paper, PPC copy paper, uncoated printing paper, and the like can be mentioned. As the paper M, those commercially available from various companies can be used, for example, Xerox 4200 (manufactured by Xerox), GeoCycle (manufactured by Georgia-Pacific), and various other types of paper can be used. Moreover, it is preferable that the paper M has a basis weight of 60 to 120 g/m ² .

Next, the ink composition used in the printing apparatus 1 (printing unit 100) of this embodiment will be described.

<Ink composition>
Next, an ink (ink composition) as a recording material used in the printing apparatus 1 (printing unit 100) of this embodiment will be described.
The ink is preferably an aqueous ink composition in which the main solvent is water, from the viewpoint of safety, handleability, and various performances (color development, strike-through aptitude, ink reliability, etc.). The strike-through aptitude refers to a property suitable for suppressing excessive penetration of ink into a recording medium and strike-through.

It is preferable to use pure water or ultrapure water such as ion-exchanged water, ultrafiltrated water, reverse osmosis water, and distilled water. In particular, it is preferable to use water that has been sterilized by ultraviolet irradiation or the addition of hydrogen peroxide in order to prevent the generation of mold and bacteria and enable long-term storage of the ink.
In addition, from the viewpoint of securing appropriate physical properties (viscosity, etc.) of the ink and securing the stability and reliability of the ink, it is preferable that the water content in the ink composition is 10% by mass to 75% by mass.

Inks include inks (for example, cyan, magenta, and yellow inks) corresponding to full-color recording (image printing and printing), black ink, white ink, and the like, each of which contains a coloring material.
As a coloring material, it is preferable that each color ink contains at least one selected from pigments, dyes, metal oxides, and the like.
Pigments are not particularly limited, but include inorganic pigments and organic pigments for black, and organic pigments of each color such as yellow, magenta, and cyan.
As dyes, various dyes such as direct dyes, acid dyes, food dyes, basic dyes, reactive dyes, disperse dyes, vat dyes, soluble vat dyes, reactive disperse dyes, etc. etc. can be used.

In addition to the colorant, the ink may contain water-soluble organic solvents, polyhydric alcohols, betaines, sugars, ureas, surfactants, and the like, in order to obtain predetermined ink properties. Predetermined ink properties include wettability and permeability of the ink to the recording medium, curling, cockling, strike-through, clogging, and ink temperature-dependent viscosity characteristics. .
Specifically, for example, water-soluble organic solvents such as 1,2-alkanediols, glycol ethers, and pyrrolidone derivatives, and polyhydric alcohols such as glycerin, 1,2,6-hexanetriol, diethylene glycol, and triethylene glycol. , tetraethylene glycol, dipropylene glycol, and the like can be used. As the surfactant, known fluorine-based surfactants, acetylene glycol-based surfactants, silicon-based surfactants, and the like can be used.

When a pigment is contained in the ink, a dispersant for dispersing the pigment may be added as another component. Further, in order to further improve the properties of the ink, a pH adjuster, a complexing agent, an antifoaming agent, an antioxidant, an ultraviolet absorber, an antiseptic/antifungal agent, and the like may be added to the ink.

<Configuration of intermediate unit>
Next, the intermediate unit 200 is described. As shown in FIG. 1 , the intermediate unit 200 includes a transport path 218 that can transport the paper M from the carry-in entrance 210 to the carry-out exit 211 . Further, the transport path 218 is provided with an intermediate transport section 252 having at least one reversing section (two first reversing sections 241 and a second reversing section 242 in this embodiment) for reversing the transported sheet M. . The first reversing section 241 and the second reversing section 242 are located downstream of the recording section 110 in the transport direction in the transport path 218, and reverse the paper M on which the image is printed. The intermediate unit 200 also includes a transport path 218 along which the paper M is transported. Therefore, the intermediate unit 200 has a drying function that dries the paper M on which an image has been printed in the printing unit 100 while transporting it, and a switchback type reversing function that reverses the paper M transported from the printing unit 100. ing.

The transport path 218 of the intermediate unit 200 is connected to the third discharge path 153 of the printing unit 100 at the carry-in port 210 . In addition, the conveying route 218 includes an introduction route 243 whose upstream end is connected to the third discharge route 153, and a first branch route 244 and a second branch route 245 that branch at a branch point A that is the downstream end of the introduction route 243. have. That is, the branch point A is connected to the downstream end of the introduction path 243, the upstream end of the first branched path 244, and the upstream end of the second branched path 245, respectively. The path lengths in the conveying direction of the first branch path 244 and the second branch path 245 are substantially the same length.

Further, the conveying route 218 is connected to a first junction route 246 connected to a first connection point B, which is the downstream end of the first branch route 244, and a second connection point C, which is the downstream end of the second branch route 245. and a second merging path 247 . The path lengths in the conveying direction of the first merging path 246 and the second merging path 247 are substantially the same length.

Also, the first connection point B is connected to a switchback-type first inversion path 248 of the first inversion section 241 . Also, the second connection point C is connected to a switchback-type second inversion path 249 of the second inversion section 242 . That is, the first connection point B is connected to the downstream end of the first branch path 244 , the upstream end of the first merging path 246 , and one end of the first reverse path 248 . Also, the second connection point C is connected to the downstream end of the second branch path 245 , the upstream end of the second merging path 247 , and one end of the second reverse path 249 . The path lengths of the first reversing path 248 and the second reversing path 249 are configured to be equal to or greater than the length of the paper M on which images can be printed by the printing unit 100 in the transport direction.

Further, the conveying route 218 is provided with a confluence D where the first confluence route 246 and the second confluence route 247 merge, and has an outlet route 250 connected to the confluence D. That is, the confluence D is connected to the downstream end of the first confluence path 246 , the downstream end of the second merge path 247 , and the upstream end of the lead-out path 250 . The lead-out path 250 extends downward toward the post-processing unit 300 between the first reversing path 248 and the second reversing path 249, then turns around the first reversing path 248 and extends upward. . The lead-out path 250 is composed of a first lead-out path 250a arranged on the upstream side and a second lead-out path 250b arranged on the downstream side of the first lead-out path 250a. The downstream end of the second lead-out path 250 b is connected to the downstream transport path 319 of the post-processing unit 300 at the outlet 211 .

In the present embodiment, the introduction route 243, the first branch route 244, and the second branch route 245 constitute the pre-reversal route 218a, the first confluence route 246, the second confluence route 247, and the outlet route. 250 constitute a post-inversion path 218b. The pre-reversal path 218a is positioned upstream in the transport direction from the first reversing section 241 or the second reversing section 242 in the transport direction. Further, the post-reversal path 218b is positioned downstream in the transport direction from the first reversing section 241 or the second reversing section 242 in the transport direction. That is, the transport path 218 has a pre-reversal path 218a located upstream in the transport direction from the first reversing section 241 and the second reversing section 242, and a post-reversal path 218b located downstream in the transport direction. ing.

Further, as shown in FIG. 3 , the intermediate unit 200 includes an intermediate transport section 252 capable of transporting the paper M along the transport path 218 . The first reversing section 241 and the second reversing section 242 in the intermediate conveying section 252 are configured to be able to reverse the sheet M being conveyed.

A first conveying roller pair 254 driven by a first driving motor (not shown) is arranged on the introduction path 243 , the first branch path 244 and the second branch path 245 . A second conveying roller pair 256 driven by a second driving motor (not shown) is arranged on the first joining path 246, the second joining path 247, and the first lead-out path 250a. A third conveying roller pair 257 driven by a third drive motor (not shown) is arranged on the second lead-out path 250b. The numbers of the first transport roller pair 254, the second transport roller pair 256, and the third transport roller pair 257 can be arbitrarily set depending on the form of each transport path. Then, while each roller pair of the intermediate transport section 252 sandwiches and supports the sheet M from both sides, one roller of the roller pair is rotationally driven to transport the sheet M along the transport path.

In addition, an introduction detection unit 258 that detects the paper M is provided in the introduction path 243 . The introduction detection unit 258 is, for example, a photointerrupter, and has the same specific configuration as the transport detection unit 199 . A guide flap 259 is provided at a branch point A on the downstream side of the introduction detection section 258 in the transport direction. The guide flap 259 is driven by a solenoid or the like, and switches between the first branched path 244 and the second branched path 245 to guide the sheet M conveyed along the lead-in path 243 .

Furthermore, at the downstream end of the first branch path 244, while allowing the movement of the paper M from the first branch path 244 to the first reversing path 248, the paper M from the first reversing path 248 to the first branch path 244 A first restricting flap 261 is provided to restrict the movement of the . Furthermore, at the downstream end of the second branch path 245, while allowing the movement of the paper M from the second branch path 245 to the second reversing path 249, the paper M from the second reversing path 249 to the second branch path 245 A second restricting flap 262 is provided to restrict the movement of the . These first regulation flap 261 and second regulation flap 262 are urged by an urging force of an urging member (not shown) so as to close the downstream end of the first branch path 244 or the second branch path 245. .

A first detection unit 281 that detects the paper M is arranged on the first branch path 244 , and a second detection unit 282 that detects the paper M is arranged on the second branch path 245 . A third detection unit 283 for detecting the paper M is arranged on the first junction path 246 . Further, a fourth detection section 284 for detecting the paper M is arranged on the first lead-out path 250a, and a fifth detection section 285 for detecting the paper M is arranged on the second lead-out path 250b. Note that the first to fifth detectors 281 , 282 , 283 , 284 , and 285 are, for example, photointerrupters, and have the same specific configuration as the transport detector 199 . The number of detection units in each transport path can be arbitrarily set according to the form of each transport path.

The first reversing unit 241 includes a first reversing detection unit 264 that detects the sheet M sent to the first reversing path 248, and a first reversing roller pair 265 (this embodiment) provided on the first reversing path 248. 2 pairs) are arranged. The first reversing roller pair 265 is driven forward or reverse by a first reversing motor (not shown) based on a signal transmitted when the first reversing detection unit 264 detects the paper M.

Further, the second reversing section 242 includes a second reversing detection section 267 that detects the sheet M sent to the second reversing path 249, and a second reversing roller pair 268 (a book sheet) provided on the second reversing path 249. In the embodiment, 5 pairs) are arranged. The second reversing roller pair 268 is driven forward or reverse by a second reversing motor (not shown) based on a signal transmitted when the second reversing detector 267 detects the paper M. Note that the first and second reversal detection units 264 and 267 are, for example, photo interrupters, and have the same specific configuration as the transport detection unit 199 . Of the second reversing roller pair 268 provided on the second reversing path 249, the two disposed on the downstream side of the second reversing path 249 are the first holding portions 269a ( 3) and a second roller pair 268b that constitutes the second holding portion 269b (see FIG. 3). Also, the first roller pair 268a is arranged downstream of the second roller pair 268b in the second reversing path 249 . In other words, the second roller pair 268b is arranged behind the first roller pair 268a in the direction in which the paper M enters the second reversing path 249 .

In addition, in the second reversing section 242, a drying unit 270 (in this embodiment, two drying units 270a and 270b) for accelerating the drying of the paper M is provided at a position facing the second reversing path 249. , see FIG. 8) are provided. The drying unit 270 is arranged upstream of the first roller pair 268a in the direction in which the paper M enters the second reversing path 249. A second drying unit 270b is arranged at a position facing the other side of the paper M. As shown in FIG. The drying unit 270 (270a, 270b) includes a blower, and the air from the blower is blown toward the sheet M. As shown in FIG. In addition, since the configuration including the heater can blow warm air toward the paper M, the drying of the paper M can be further accelerated.

Also, in the second reversing section 242, two guide plates 271 for linearly guiding the paper M so as to sandwich the second reversing path 249 are provided at positions facing one side of the paper M and the other side of the paper M. are arranged at positions facing the surfaces of the . The guide plate 271 has a flat plate shape and is provided with through-holes in a mesh shape, and is processed so that air from the blower of the drying unit 270 (270a, 270b) can easily hit the paper M. Further, the guide plate 271 may be frame-shaped with an opening in the center, and may be configured such that a plurality of wire rods are provided in the opening along the transport direction.

<Configuration of post-processing unit>
Next, the post-processing unit 300 will be described. As shown in FIG. 1, the post-processing unit 300 has a substantially box-shaped frame 320 . The frame 320 has a post-processing paper feed port 322 and a post-processing paper discharge port 323 . The post-processing paper feed port 322 and the post-processing paper discharge port 323 are each formed with an opening. 218 and the downstream transport path 319 are connected. The downstream transport path 319 is arranged from the post-processing paper feed port 322 to the post-processing paper discharge port 323, and the paper M transported from the intermediate unit 200 is supplied from the post-processing paper feed port 322, and the paper M After performing post-processing and the like on the paper, the paper is discharged from the post-processing paper discharge port 323 .

A stacker 328 , a processing unit 325 and the like are arranged inside the frame 320 . The stacker 328 temporarily stacks the paper M, and has a stacking surface 328a having a substantially flat surface on which the paper M can be placed, and a stacker 328 formed substantially perpendicular to the edge of the stacking surface 328a. and a wall surface 328b.

The processing unit 325 performs a punching process for punching holes in the sheets M placed on the stacker 328, a stapling process for binding the sheets M by a predetermined number of sheets, and a position of the sheets M in the width direction. Post-processing such as shift processing is performed by an appropriate mechanism by shifting the sheet or bundle in the width direction. Note that the processing unit 325 includes a mechanism that can perform a paper folding unit that folds the paper M, a cutting process that cuts the paper M, a signature process that folds the paper M, a bookbinding process that binds the paper M, a collating process, and the like. may be provided.

A downstream transport section 335 is arranged along the downstream transport path 319 inside the frame 320 . The downstream transport section 335 has a pair of transport rollers 327 driven by drive rollers (not shown). A paper discharge roller pair 329 is arranged in the vicinity of the post-processing paper discharge port 323 in the downstream transport path 319 . The transport roller pair 327 is arranged upstream of the stacker 328 and the processing section 325 in the downstream transport path 319 and transports the paper M fed from the post-processing paper feed port 322 to the stacker 328 . A transport detection unit 356 that detects the paper M is arranged near the post-processing paper feed port 322 in the downstream transport path 319 . The transport detection unit 356 is, for example, a photointerrupter, and has the same specific configuration as the transport detection unit 199 .

Further, inside the frame 320 , a guide portion 330 is provided to guide the sheet M conveyed along the downstream conveying path 319 . The guide portion 330 has a protrusion shape. The guide portion 330 includes a guide surface 330a having a substantially flat surface, and the guide surface 330a is arranged to face the downstream transport path 319 (stacker 328). The width of the guide surface 330a of the present embodiment, which is substantially perpendicular to the transport direction of the paper M, is substantially the same as the width of the paper M which is substantially perpendicular to the transport direction. As a result, the paper M can be easily transported. The guide section 330 is arranged downstream of the transport roller pair 327 and upstream of the paper discharge roller pair 329 in the downstream transport path 319 . Accordingly, the paper M transported from the transport roller pair 327 is transported to the stacker 328 via the guide section 330 .

The stacker 328 of the present embodiment is arranged downstream of the transport roller pair 327 in the downstream transport path 319 and temporarily stacks the paper M to be processed by the processing section 325 . A stacking surface 328a of the stacker 328 is arranged obliquely so that at least one edge side of the plurality of sheets M placed on the stacker 328 are aligned. In this embodiment, one end of the stacker 328 is arranged on the side of the post-processing discharge port 323 , and the other end (wall surface 328 b ) of the stacker 328 is arranged on the side of the processing section 325 . The post-processing discharge port 323 is arranged above the processing section 325 , and the stacker 328 is arranged obliquely downward toward the processing section 325 . As a result, one end side of the paper sheets M placed on the stacker 328 contacts the wall surface 328b of the stacker 328, thereby aligning one end side of the paper sheets M. FIG.

<Method of operation of printing device>
Next, a basic operating method of the printing apparatus 1 will be described. 4 to 7 are schematic diagrams showing how the printing apparatus operates. In the following description, the transport mode of the paper M transported from the printing unit 100 to the post-processing unit 300 via the intermediate unit 200 will be described. It should be noted that the paper M supplied to the recording head 111 of the printing unit 100 and conveyed is referred to as the first paper Ma, the second paper Mb, and the third paper Mc in order from the first sheet, and the fourth paper M is the fourth paper. Md, and four sheets M are all sheets M for which drying is omitted.

First, when print processing (image print processing) is executed, the control unit 10 drives each drive motor. As a result, a pickup roller 142a connected to each drive motor, a transport roller pair 131, a drive roller 133, a first transport roller pair 254, a second transport roller pair 256, a third transport roller pair 257, and a first reversing roller pair 265 , the second reversing roller pair 268, the conveying roller pair 327, and the like are driven.

Then, the recording unit 110 ejects ink from the recording head 111 onto the paper M to print an image. In this case, the printing process may be single-sided printing or double-sided printing.

Then, as shown in FIG. 4, the first sheet Ma conveyed through the third discharge path 153 at the pre-reversal speed is transferred to the introduction path 243 at substantially the same speed. Then, when the introduction detection unit 258 detects the leading edge of the first sheet Ma, the control unit 10 drives the solenoid to position the guide flap 259 at the first position P1. That is, the guide flap 259 guides the first sheet Ma to the first branch path 244 . The leading edge of the first sheet Ma transported to the first connection point B contacts the first regulation flap 261 to move the first regulation flap 261 against the biasing force of the biasing member. That is, the first regulation flap 261 moves so as to open the downstream end of the first branch path 244 . Therefore, the first sheet Ma is sent to the first reversing path 248 at the pre-reversal speed by the first reversing roller pair 265 that is driven to rotate in the normal direction. Then, when the first sheet Ma passes through the first regulation flap 261, the first regulation flap 261 moves from the position to open the downstream end of the first branch path 244 to the position to close it.

As shown in FIG. 5, when the first reversal detection unit 264 detects the trailing edge of the first sheet Ma, the control unit 10 switches the first reversing roller pair 265, which was normally driven, to reverse rotation. Then, the first reversing section 241 feeds the first sheet Ma from the first reversing path 248 to the first connection point B side at the post-reversal speed. Also, at this time, the first regulation flap 261 guides the first sheet Ma to the first joining path 246 . That is, the first reversing section 241 reverses (switches back) the orientation of the first sheet Ma by feeding the first sheet Ma sent from the first branch path 244 to the first joining path 246 .

Also, when the introduction detection unit 258 detects the leading edge of the second sheet Mb, the control unit 10 drives the solenoid to change the position of the guide flap 259 . That is, the control unit 10 moves the guide flap 259 positioned at the first position P1 to the second position P2. The guide flap 259 then guides the second sheet Mb to the second branch path 245 .

As shown in FIG. 6, the first sheet Ma reversed by the first reversing section 241 is conveyed through the post-reversal path 218b at the post-reversal speed. Then, when the first sheet Ma passes through the first connection point B, the controller 10 rotates the first reversing roller pair 265 forward. Further, the control section 10 reversely rotates the second reversing roller pair 268 when the second reversing detection section 267 detects the trailing edge of the second sheet Mb. In other words, the second reversing section 242 reverses the second sheet Mb in the same manner as the first reversing section 241 and sends it to the second merging path 247 at the post-reversal speed.

Furthermore, when the introduction detection unit 258 detects the leading edge of the third paper Mc, the control unit 10 drives the solenoid to change the position of the guide flap 259 . Specifically, the control unit 10 moves the guide flap 259 positioned at the second position P2 to the first position P1. That is, the guide flap 259 alternately guides the conveyed sheet M to the first branch path 244 and the second branch path 245 .

As shown in FIG. 7, the second sheet Mb reversed by the second reversing section 242 and sent to the second merging path 247 is conveyed through the deriving path 250 via the merging point D. As shown in FIG. Note that, at this time, the intermediate conveying unit 252 conveys the first sheet Ma and the second sheet Mb at a post-reversal speed that is lower than the pre-reversal speed. Therefore, the interval in the transport direction between the first sheet Ma and the second sheet Mb is narrower than when the sheets are transported through the pre-reversal path 218a at the pre-reversal speed.

Then, when the first reversal detection section 264 detects the trailing edge of the third sheet Mc, the control section 10 reversely rotates the first reversing roller pair 265 to feed the third sheet Mc to the first joining path 246 . Further, when the introduction detection unit 258 detects the leading edge of the fourth sheet Md, the control unit 10 drives the solenoid to change the position of the guide flap 259 to the second position P2.

Then, the intermediate unit 200 feeds out the first paper Ma introduced earlier to the post-processing unit 300 in order. That is, the sheet M is reversed in the intermediate unit 200 and sent to the post-processing unit 300 . In addition, since the downstream-side transport section 335 transports the paper M at a processing speed faster than the post-reversal speed, the distance between the papers M increases. Then, the sheets M are successively conveyed to the stacker 328 , and when a predetermined number of sheets of the sheets M are placed on the stacker 328 , processing such as stapling is performed by the processing unit 325 . discharged to

Next, problems related to the post-processing unit 300 of this embodiment will be described. As described above, when the printing unit 100 is an inkjet printer including the recording head 111 that ejects ink droplets, the paper M on which an image is printed by the printing unit 100 absorbs ink (moisture) or loses ink. Curling (a state in which the paper is curved or a state in which the paper is curled) may occur due to drying or the like. Therefore, in the stacker 328, if the degree of curling of the paper M that is placed earlier becomes large, there is a possibility that the paper M that is transported later will curl due to the curl of the paper M that has been placed earlier, causing a stacking failure. There is Further, if the ink (moisture) on the paper M on which an image has been printed by the printing unit 100 is not sufficiently dried, the moisture remains on the surface of the paper M, and the frictional resistance of the surface of the paper M increases. Therefore, when the sheets of paper M on which images have been printed by the printing unit 100 (inkjet printer) are sequentially stacked on the stacker 328, if the frictional resistance of the surface of the sheets of paper M that has been placed earlier increases, There is a possibility that the sheet M to be conveyed is caught by the sheet M that was placed first, and the edges of the sheet M become uneven, resulting in misalignment.

Further, the mechanism of curling of the paper M will be described in detail. The paper M of this embodiment is mainly composed of cellulose, and the cellulose is formed by hydrogen bonding. Therefore, when ink is applied to one side of the paper M by the printing unit 100, hydrogen bonds between celluloses are broken due to absorption of the ink. As a result, the space between the cellulose particles widens, and the one surface of the paper M coated with ink becomes easier to stretch than the other surface of the paper M opposite to the one surface. Therefore, when the paper M is placed with one side facing the direction of gravity (downward), the paper M curls convexly in the direction of gravity (primary curl).
Further, after the primary curl occurs, as the drying of the ink absorbed by the sheet of paper M progresses, the celluloses are freely linked by hydrogen bonding, and the spacing between the celluloses narrows. Then, one surface of the paper M coated with ink shrinks more than the other surface. Therefore, when the paper M is placed with one surface facing the direction of gravity, the paper M is concave with respect to the direction of gravity (convex in the direction opposite to the direction of gravity), contrary to the case of the primary curl. shape) (secondary curl).

Further, the occurrence of curling of the paper M is not limited to single-sided printing, and occurs similarly in double-sided printing. That is, when the printing duty on one side of the paper M is different from the printing duty on the other side of the paper M, the paper M tends to curl. In particular, when the difference between the printing duty on one side of the paper M and the printing duty on the other side is greater than a predetermined value (for example, about 30% or more), the curling of the paper M becomes significant. Note that the "duty" is duty (%) = number of actual recorded dots / (vertical resolution x horizontal resolution) x 100 (wherein "number of actual recorded dots" is the number of actual recorded dots per unit area, and " "vertical resolution" and "horizontal resolution" are resolutions per unit area). Also, the difference in printing duty of the paper M means the difference in water content between the front and back sides of the paper M (one side and the other side).

Therefore, the intermediate unit 200 includes a drying unit 270 that suppresses insufficient drying and deformation (curling) of the paper M placed on the stacker 328 of the post-processing unit 300 . The drying unit 270 can reduce the occurrence of misalignment due to high frictional resistance of the paper M placed on the stacker 328 and stack failure due to curling.

<Drying unit>
Next, the operation of the drying unit 270 provided in the intermediate unit 200 will be described. FIG. 8 is a schematic diagram explaining the operation of the drying unit.
The paper M requiring drying is sent to the second reversing path 249 in which the drying unit 270 is provided according to the print duty as print data. As shown in FIG. 8, the sheet M that has entered the second reversing path 249 has a portion closer to the trailing edge of the sheet M than the leading edge of the sheet M in the direction in which the sheet M enters the second reversing path 249, as shown in FIG. It is held by a first roller pair 268a that constitutes one holding portion 269a (see FIG. 3). After that, the drying unit 270 is driven according to the printing duty, and the blower of the drying unit 270 blows the air W, thereby accelerating the drying of the paper M. The sheet M is guided by the guide plate 271 in a flat state and is exposed to the blown air, so deformation such as curling of the sheet M due to the wind pressure can be easily suppressed.

Next, another configuration of the drying unit 90 provided in the intermediate unit 200 will be described with reference to FIGS. 9 to 12. FIG.
FIG. 9 is a configuration diagram showing another configuration of the drying unit provided in the intermediate unit, and FIG. 10 is an enlarged perspective view around the second reversing path in another configuration of the drying unit provided in the intermediate unit. 11 is a view of FIG. 10 viewed from another angle. 12 is a cross-sectional view along the line JJ of the second inversion path shown in FIG. 10, and FIG. 13 is a cross-sectional view along the line KK of the second inversion path shown in FIG.

In the XYZ coordinate system shown in each figure, the X-axis direction is the conveying direction of the recording medium (paper M) in the conveying path in the intermediate unit 200, the device width direction is shown, and the Y-axis direction is the recording direction. The width direction of the medium (paper M) indicates the depth direction of the device, and the Z-axis direction indicates the height direction of the device.
The intermediate unit 200 is provided with two drying units 90 (a first drying unit 90a and a second drying unit 90b) along the X-axis direction with the second reversing path 249 interposed therebetween. In the present embodiment, the drying unit 90 (90a, 90b) includes an air blower and is provided to blow air toward the second reversing path 249 (see FIGS. 10 and 11).

The second reversing path 249 includes an inner path surface 91 located inside the curve of the second reversing path 249 and an outer path surface 92 located outside the curve of the second reversing path 249. The first drying unit 90 a is arranged to send air toward the inner path surface 91 and the second drying unit 90 b is arranged to send air toward the outer path surface 92 .

A plurality of slit portions 93 are provided on each of the outer path surface 92 and the inner path surface 91 . The slit portion 93 has an elongated shape in the transport direction (X-axis direction). By providing the slit portions 93 on the outer path surface 92 and the inner path surface 91, the effect of drying the paper M by the wind sent from the first drying unit 90a and the second drying unit 90b is enhanced.

As shown in FIG. 9, the second reversing path 249 has a curved portion 94 (FIGS. 10 and 11) that once curves in the conveying direction from the branch point C to the second reversing path 249, and and a linear portion 95 extending linearly from the bottom. The inner path surface 91 is provided only at the central portion of the straight portion 95 in the width direction (Y-axis direction) that intersects the conveying direction (X-axis direction) of the paper M.

As shown in FIG. 12, in the vicinity of the widthwise center of the second reversing path 249, the sheet M is sandwiched by both the outer path surface 92 and the inner path surface 91 from the curved portion 94 to the straight portion 95. It is With this configuration, it is possible to hold down the sheet M from the curved portion 94 to the straight portion 95 and realize stable transportation of the sheet M in the second reversing path 249 .

On the other hand, as shown in FIG. 13, on the width direction end side, the sheet M is sandwiched between both the outer path surface 92 and the inner path surface 91 at the curved portion 94, but at the straight portion 95, the outer path surface The paper M is supported only by 92. With this configuration, it is possible to easily handle a paper jam or the like in the second reversing path 249 .
12 and 13, reference numeral 96 denotes a serrated roller provided with a plurality of projections on its periphery and configured to come into point contact with the paper M. As shown in FIG.
With the configuration as described above, the drying of the paper M can be accelerated, and the deformation of the paper M such as curling can be easily suppressed.

<Method of Operation of Printing Apparatus Equipped with Drying Unit in Intermediate Unit>
Next, the operation method of the printing apparatus 1 having the drying unit 270 in the intermediate unit 200 will be described. FIG. 14 is a flow chart showing a method of operation of a printing apparatus having a drying unit in the intermediate unit. Note that one side of the sheet of paper M will be described as the front side, and the other side of the sheet of paper M that faces the one side will be described as the back side.
First, a print job signal is received from the control unit 10 (step S1-1). Next, an image is printed on the paper M in the printing unit 100 based on the print job signal (step S1-2). The paper M on which the image is printed is transported to the intermediate unit 200 having the transport path 218 .

After that, in the introduction path 243 of the intermediate unit 200, depending on the print duty as the print data from the control unit 10, the first reverse path 248 in which the drying unit 270 is not provided or the first reversing path 248 in which the drying unit 270 is provided 2 Inversion path 249 is selected. That is, when the print duty is equal to or greater than a predetermined threshold value (for example, 50%), the paper M is sent to the second reversing path 249 provided with the drying unit 270, and the drying unit 270 is driven to dry the paper M. Further, when the print duty is less than a predetermined threshold value (for example, 50%), the paper M does not need to be dried, so it is sent to the first reversing path 248 in which the drying unit 270 is not provided. That is, the paper M having a difference in water content between the front and back surfaces of the paper M based on the print duty is equal to or greater than a predetermined threshold is conveyed through the second reversing path 249 provided with the drying unit 270, and the paper M having the print duty less than the predetermined threshold is transported. M conveys the first reversing path 248 on which the drying unit 270 is not provided.

In step S1-3, it is determined whether or not the printing duty of the front side is equal to or greater than a predetermined threshold.
Both steps S1-4 and S1-5 are steps for determining whether or not the printing duty on the back side is equal to or greater than a predetermined threshold. No", go to step S1-7.

Also, in step S1-5, if "Yes", the process proceeds to step S1-8. After being switched back on the upstream side of the drying unit 270 in the direction of entry into the path and being reversed via the first reversing path 248, it is conveyed to the post-processing unit 300, and the process proceeds to step S1-9. In the case where the drying of the paper M is omitted, the second reversing path 249 provided with the drying unit 270 may be used to reverse the paper M. FIG. In this case, the paper M is switched back upstream of the drying unit 270 in the direction in which the paper M enters the second reversing path 249 and is reversed, thereby shortening the transport distance and the transport time. can be processed.

In step S1-6, the sheet of paper M is sent to the second reversing path 249 provided with the drying unit 270, both sides of the sheet M are dried by the drying unit 270, and after being reversed by switching back the second reversing path 249, It is conveyed to the post-processing unit 300 and proceeds to step S1-9. At this time, the driving of the first drying unit 270a and the second drying unit 270b is independently controlled according to the printing duty of both sides of the paper M. FIG. That is, by adjusting the drying conditions (blowing strength and blowing time) of the first drying unit 270a and the second drying unit 270b according to the printing duties of the front and back surfaces, the degree of dryness of both sides of the paper M is made substantially the same. Therefore, deformation of the paper M due to secondary curling or the like can be suppressed.

In step S1-7, since the surface needs to be dried, the sheet M is sent to the second reversing path 249, the drying unit 270 dries the surface of the sheet M, and after switching back the second reversing path 249 and reversing, , is conveyed to the post-processing unit 300, and the process proceeds to step S1-9.
In step S1-8, since the back surface needs to be dried, the sheet M is sent to the second reversing path 249, the drying unit 270 dries the back surface of the sheet M, and the sheet M is switched back through the second reversing path 249 to be reversed. , is conveyed to the post-processing unit 300, and the process proceeds to step S1-9.

In step S1-9, the transported paper M is transported to the stacker 328 via the guide section 330, and placed on the stacker 328 with one side of the paper M aligned. After that, the processing unit 325 performs a punching process for punching holes in the sheets M placed on the stacker 328, a stapling process for binding the sheets M every predetermined number of sheets, and a width direction of the sheets M. Post-processing such as shift processing is performed to adjust the position of the sheet by shifting it in the width direction for each sheet or for each bundle.

As described above, according to the printing apparatus 1 having the drying unit 270 according to the first embodiment, the following effects can be obtained.
Since the drying unit 270 that promotes drying of the paper M is provided in the transport path of the intermediate unit 200, the paper M can be sufficiently dried by the drying unit 270 during transport, thereby suppressing the occurrence of curling. In addition, it is possible to provide the intermediate unit 200 that can reduce the frictional resistance of the paper M due to the water content of the ink. Therefore, when the paper M discharged from the intermediate unit 200 is subjected to post-processing, it is possible to reduce stacking defects due to curling of the printed paper M and misalignment due to high frictional resistance.

In addition, since the reversing paths 248 and 249 are provided in the transport path 218, the front and back of the paper M can be reversed during transport.

In addition, since the drying unit 270 is provided in the second reversing path 249 in which a long area for straightening the paper M can be secured, the size of the intermediate unit 200 can be reduced.

Further, since the drying unit 270 is provided in the second reversing path 249 among the plurality of reversing paths 248 and 249, the intermediate unit 200 can be miniaturized and the power consumption can be reduced.

In addition, by selecting one of the plurality of reversing paths 248 and 249 according to the print duty as the print data of the paper M, the intermediate unit 200 efficiently reverses the paper M. It can be carried out.

Further, if the difference in water content between the front and back sides of the paper M based on the print data is equal to or greater than a predetermined threshold value, the drying unit 270 can be driven to dry the paper M, thereby suppressing the occurrence of curling. Also, the frictional resistance of the paper M due to moisture in the ink can be reduced.

In addition, by conveying the paper M whose print data is equal to or greater than the predetermined threshold to the second reversing path 249 provided with the drying unit 270, the paper M can be dried, thereby suppressing the occurrence of curling. Also, the frictional resistance of the paper M due to the water content of the ink can be reduced.

Further, by providing the first drying unit 270a facing one side of the paper M and the second drying unit 270b facing the other side of the paper M, both sides of the paper M can be dried at the same time. Therefore, drying can be promoted more.

In addition, by independently controlling the driving of the first drying unit 270a and the second drying unit 270b according to the printing duty, the balance between the drying conditions of one side and the other side of the paper M can be achieved. It is possible to suppress deformation of the paper M due to curling, secondary curling, or the like.

In addition, since the drying unit 270 includes an air blower, the paper M is dried by blowing air from the air blower when drying the paper M, so deformation such as curling of the paper M due to the wind pressure of the air blow can be easily suppressed. Also, since no heat source is used, power consumption of the intermediate unit 200 can be reduced.

Further, by holding the paper M at a portion near the rear end of the paper M in the first holding portion 269a downstream of the air blower of the drying unit 270, the air can be applied to the paper M, and the paper M can be straightened. It is possible to take a long area to be shaped. Therefore, the paper M can be dried in a straight state, and deformation such as curling of the paper M can be easily suppressed.

Further, by switching back the sheet M for which drying is omitted on the upstream side of the drying unit 270, the conveying distance and the conveying time can be shortened, so that the reversing process can be performed at high speed.

In addition, since the printed paper M can be sufficiently dried by the drying unit 270 provided in the transport path 218, the occurrence of curling can be suppressed, and the frictional resistance of the paper M caused by the water content of the ink can be reduced. can do. Therefore, it is possible to provide the post-processing device 2 that reduces stacking defects due to curling of the printed sheets M and misalignment due to high frictional resistance when the sheets M are subjected to post-processing.

In addition, since the reversing paths 248 and 249 are provided in the transport path 218, it is possible to provide the post-processing device 2 capable of reversing the front and back of the paper M during transport.

In addition, since the printed paper M can be sufficiently dried by the drying unit 270 provided in the transport path 218, the occurrence of curling can be suppressed, and the frictional resistance of the paper M caused by the water content of the ink can be reduced. can do. Therefore, it is possible to provide the printing apparatus 1 that reduces stacking defects due to curling of the printed paper M and misalignment due to high frictional resistance when the paper M is post-processed.

(Second embodiment)
Next, the tensioning mechanism of the intermediate unit 200a according to the second embodiment of the invention will be described. 15A and 15B are schematic diagrams for explaining the operation of the tension applying mechanism of the intermediate unit according to the second embodiment. In addition, the same numbers are attached to the same constituent parts as in the first embodiment, and redundant explanations are omitted.
The intermediate unit 200a according to the second embodiment differs from the intermediate unit 200 according to the first embodiment in that it does not have a guide plate 271 that guides the paper M during drying, and is provided with a tension applying mechanism.

<Tensioning mechanism>
The intermediate unit 200a is provided with a tension applying mechanism that applies tension to the paper M in order to suppress deformation of the paper M such as curling. The tensioning mechanism is provided on the second reversing path 249 as shown in FIG. The tension applying mechanism includes a first roller pair 268a having a first holding portion 269a that pinches and holds one end of the paper M, and a second roller pair 269b that pinches and holds the other end of the paper M. It is composed of two roller pairs 268b and a displacement device (not shown) that changes the relative position of the first roller pair 268a with respect to the second roller pair 268b along the second reversing path 249 (conveyance path 218). Since the first holding unit 269a and the second holding unit 269b are configured by a pair of rollers that sandwich the paper M, the paper M is held by stopping the rotation of the rollers after the paper M is sandwiched. be able to.

The paper M supplied to the second reversing path 249 having a tension applying mechanism passes through the rotating second roller pair 268b and is nipped by the rotating first roller pair 268a. Next, when the position of the first roller pair 268a with respect to the paper M reaches the holding position where the paper M should be held (the position at the distance L1 from the leading edge of the paper M), the rotation of the first roller pair 268a is stopped, and the 1 holding portion 269a holds sheet M. After that, a displacement device (not shown) rotates the second roller pair 268b to move the first roller pair 268a in the direction in which the paper M enters (in the direction of the arrow of the broken line). The relative position of pair 268a is changed.

Next, when the paper M reaches the holding position where the second roller pair 268b should hold (the position of the distance L2 from the end of the paper M), the rotation of the second roller pair 268b is stopped, and the paper is held by the second holding portion 269b. Hold M. After that, a displacement device (not shown) is used to move the first roller pair 268a in the direction in which the paper M enters (in the direction of the dashed arrow), thereby creating tension between the first holding portion 269a and the second holding portion 269b. The resulting paper sheet M can be tensioned.

After the tension is applied to the paper M, the displacement device (not shown) moves the first roller pair 268a in the direction opposite to the direction in which the paper M enters while rotating the second roller pair 268b in the reverse direction. After that, when the first roller pair 268a reaches the initial position of the first roller pair 268a, the first roller pair 268a is reversely rotated, so that the tensioned paper M is switched back on the second reverse path 249. After being reversed, it is transported to the post-processing unit 300 .

In this embodiment, in order to apply tension to the paper M, the position of the second roller pair 268b that holds the paper M is fixed, and the first roller pair 268a that holds the paper M is moved in the direction in which the paper M advances. Although it is moved, it is not limited to this, and a method of moving the second roller pair 268b holding the paper M in a direction opposite to the entering direction of the paper M, or a method of moving the first roller pair 268a and the second roller pair 268b may be moved in the direction opposite to the direction in which they face each other.

Further, after the first roller pair 268a holding the leading end of the paper M moves a predetermined distance in the entering direction of the paper M, the second roller pair 268b holds the trailing end of the paper M, that is, the second The positions of the first roller pair 268a and the second roller pair 268b are fixed while the first roller pair 268a and the second roller pair 268b hold both ends (leading edge side and trailing edge side) of the paper M at a predetermined interval. However, a method in which only the first roller pair 268a is rotated forward or a method in which only the second roller pair 268b is rotated in reverse may be used to apply tension to the paper M.

<Method of Operating a Printing Apparatus Equipped with a Tensioning Mechanism in an Intermediate Unit>
Next, the operation method of the printing apparatus 1 having the tension applying mechanism in the intermediate unit 200a will be described. FIG. 16 is a flow chart showing a method of operating a printing apparatus having a tension applying mechanism in the intermediate unit. Note that one side of the sheet of paper M will be described as the front side, and the other side of the sheet of paper M that faces the one side will be described as the back side.
First, a print job signal is received from the control unit 10 (step S2-1). Next, an image is printed on the paper M in the printing unit 100 based on the print job signal (step S2-2). The paper M on which the image is printed is transported to the intermediate unit 200a having the transport path 218. As shown in FIG.

After that, in the introduction path 243 of the intermediate unit 200a, depending on the printing duty difference between the front and back surfaces of the paper M as print data from the control unit 10, a first reversing path 248 not provided with a tension applying mechanism or a tension applying mechanism Select the second reversing path 249 provided with the mechanism. That is, when the printing duty difference between the front and back surfaces of the paper M is equal to or greater than a predetermined threshold value (for example, 30%), the paper on which the image is printed is sent to the second reversing path 249 provided with a tension imparting mechanism. Apply tension to M. Further, when the print duty difference between the front and back surfaces of the paper M is less than a predetermined threshold value (for example, 30%), it is not necessary to apply tension to the paper M. Therefore, the sheet M is sent to the first reversing path 248 or the second reversing path 249 to be reversed.

In step S2-3, it is determined whether or not the printing duty difference between the front and back surfaces of the paper M is equal to or greater than a predetermined threshold. Since there is no need to add , after the sheet is reversed via the first reversing path 248 or the second reversing path 249, it is conveyed to the post-processing unit 300, and the process proceeds to step S2-5. In addition, when it is not necessary to apply tension to the paper M, when using the second reversing path 249 provided with the tension applying mechanism in order to reverse the paper M, a switch is placed on the upstream side of the tension applying mechanism. It does not matter if it is backed up and reversed. By doing so, the conveying distance and the conveying time can be shortened, so that the reversing process can be performed at high speed.

In step S2-4, the sheet M is sent to the second reversing path 249 provided with a tension applying mechanism, tension is applied to the sheet M by the tension applying mechanism, and after switching back and reversing the second reversing path 249, It is transported to the post-processing unit 300 and proceeds to step S2-5. At this time, the magnitude of the tension applied to the paper M is changed according to the printing duty difference between the front and back surfaces of the paper M. FIG. For example, if the print duty difference is large, that is, if the paper M contains a lot of moisture, the tensile strength of the paper M is weak. Further, the time for applying tension to the paper M may be changed according to the printing duty difference between the front and back surfaces of the paper M. FIG. For example, when the print duty difference is small, the tension application time is shortened.

Also, depending on the print duty difference between the front and back surfaces of the paper M, the holding positions where the paper M should be held (the position at the distance L1 from the leading end of the paper M and the position at the distance L2 from the end of the paper M) are moved closer or further away. I don't mind. That is, when the area to which tension is applied to the paper M is on the leading edge side of the paper M, the holding position of the second holding portion 269b is set to the central portion of the paper M (the distance L2 becomes longer). In addition, when the sheet M is located in the central portion, the holding positions of the first holding portion 269a and the second holding portion 269b are set closer to the central portion of the sheet M (both the distance L1 and the distance L2 become longer). Therefore, the tension can be efficiently applied to the area of the paper M to which the tension is applied.

Note that the drying unit 270 including a blower may blow air toward the sheet M to which tension is applied by the tension applying mechanism. By drying the paper M by blowing air, it is possible to suppress deformation of the paper M such as secondary curling due to insufficient drying in the transport path 218 including the second reversing path 249 and an increase in the frictional resistance of the paper M. can.

In step S2-5, the transported paper M is transported to the stacker 328 via the guide section 330, and placed on the stacker 328 with one side of the paper M aligned. After that, the processing unit 325 performs a punching process for punching holes in the sheets M placed on the stacker 328, a stapling process for binding the sheets M every predetermined number of sheets, and a width direction of the sheets M. Post-processing such as shift processing is performed to adjust the position of the sheet by shifting it in the width direction for each sheet or for each bundle.

As described above, according to the printing apparatus 1 having the tension applying mechanism in the intermediate unit 200a according to the second embodiment, the following effects can be obtained.
Since the tension applying mechanism for applying tension to the paper M is provided in the transport path 218 of the intermediate unit 200a, the shape of the paper M can be held flat and corrected by the tension applying mechanism during transport. , it is possible to provide the intermediate unit 200a capable of suppressing curling of the paper M. Therefore, when the paper M discharged from the intermediate unit 200a is subjected to post-processing, it is possible to reduce the occurrence of stack failure due to deformation such as curling of the printed paper M. FIG.

In addition, since the reversing paths 248 and 249 are provided in the transport path 218, the front and back of the paper M can be reversed during transport.

Further, by moving the first holding portion 269a by a displacement device that changes the relative position of the first holding portion 269a that holds the other side of the paper M with respect to the second holding portion 269b that holds one side of the paper M, Tension is generated between the first holding portion 269a and the second holding portion 269b, and the sheet M can be tensioned. Therefore, the shape of the sheet of paper M can be maintained and corrected in a planar state, so that the occurrence of curling can be suppressed.

Further, since the first holding portion 269a and the second holding portion 269b are composed of a pair of rollers that sandwich the paper M, the paper M is held by stopping the rotation of the rollers after the paper M is sandwiched. be able to.

Further, when the position of the first roller pair 268a with respect to the paper M reaches the holding position where the paper M should be held, the rotation of the first roller pair 268a is stopped, and the paper M is held by the first holding portion 269a. By changing the relative position of the first roller pair 268a with respect to the second roller pair 268b, when the sheet M reaches the holding position to be held by the second roller pair 268b, the rotation of the second roller pair 268b is stopped, and the second holding portion 269b to hold the sheet M. Therefore, tension can be applied to the sheet M by generating tension between the first holding portion 269a and the second holding portion 269b.

In addition, by changing the holding positions of the first roller pair 268a and the second roller pair 268b to hold the paper M according to the printing duty difference between the front and back surfaces of the paper M, the tension is applied to the area of the paper M. Tension can be applied efficiently.

Further, by changing the magnitude of the tension applied to the paper M according to the printing duty difference between the front and back surfaces of the paper M, the shape of the paper M can be maintained and corrected flat without damaging the paper M. can be done.

Further, by changing the time for applying tension to the paper M according to the printing duty difference between the front and back surfaces of the paper M, the shape of the paper M can be held flat and corrected in a short period of time.

In addition, since the tension applying mechanism is provided in the second reversing path 249 that can take a long area for straightening the paper M, the size of the intermediate unit 200a can be reduced.

In addition, since the tension applying mechanism is provided in the second reversing path 249, which is a part of the plurality of reversing paths (248, 249), it is possible to reduce the size and power consumption of the intermediate unit 200a.

In addition, the paper M can be dried by blowing air toward the paper M to which tension is applied. Therefore, it is possible to suppress deformation of the sheet M such as secondary curling due to insufficient dryness in the transport path 218 including the second reversing path 249 and an increase in the frictional resistance of the sheet M.

Further, since the tension applying mechanism provided in the transport path 218 can hold the shape of the printed paper M flat and correct the shape of the paper M, curling of the paper M can be suppressed. Therefore, it is possible to provide the post-processing device 2 that reduces the occurrence of stacking defects due to curling of the printed paper M when the paper M is subjected to post-processing.

Further, since the tension applying mechanism provided in the transport path 218 can hold the shape of the printed paper M flat and correct the shape of the paper M, curling of the paper M can be suppressed. Therefore, it is possible to provide the printing apparatus 1 that reduces the occurrence of stacking defects due to curling of the printed paper M when the paper M is post-processed.

(Modification 1)
Next, the tension applying mechanism of the intermediate unit 200b according to Modification 1 of the second embodiment of the present invention will be described. 17A and 17B are schematic diagrams for explaining the operation of the tensioning mechanism of the intermediate unit 200b according to Modification 1 of the second embodiment. In addition, the same numbers are attached to the same constituent parts as in the second embodiment, and redundant explanations are omitted.

The intermediate unit 200b according to Modification 1 differs from the intermediate unit 200a of the second embodiment in that a pressure roller 280 is provided in the tension applying mechanism.
The intermediate unit 200b is provided with a pressure roller 280 in the tension applying mechanism. The pressure roller 280 is arranged at a position facing the paper M downstream of the second roller pair 268 b in the direction in which the paper M enters the second reversing path 249 .

The method of applying tension to the printed paper M in Modification 1 is such that the first roller pair 268a and the second roller pair 268b hold the paper M at a predetermined interval, and the positions of the first roller pair 268a and the second While the position of the roller pair 268b is fixed, the pressure roller 280 is brought into contact with the central portion of the paper M, and then the pressure roller 280 is moved in a direction intersecting the direction in which the paper M enters the second reversing path 249. It is to move.

In this embodiment, tension is applied to the paper M by moving the pressure roller 280, but the present invention is not limited to this, and the pressure roller 280 may be an elliptical roller or an eccentric roller. . By using an elliptical roller or an eccentric roller as the pressure roller 280, tension can be applied to the paper M simply by rotating the pressure roller 280, and the configuration can be simplified.

With such a configuration, tension can be generated between the first roller pair 268a and the second roller pair 268b that hold the paper M, so that the paper M can be tensioned. Therefore, the shape of the sheet of paper M can be held flat and corrected, so that the intermediate unit 200b that can suppress the occurrence of curling can be provided.

(Third embodiment)
Next, the liquid ejection unit 290 of the intermediate unit 200c according to the third embodiment of the invention will be described. 18A and 18B are schematic diagrams for explaining the operation of the liquid ejection unit of the intermediate unit according to the third embodiment. In addition, the same numbers are attached to the same constituent parts as in the first embodiment, and redundant explanations are omitted. Note that one side of the sheet of paper M will be referred to as the front side, and the other side of the sheet of paper M will be referred to as the back side.
The intermediate unit 200c according to the third embodiment differs from the intermediate unit 200 according to the first embodiment in that it does not have the drying unit 270, but has a liquid jetting unit 290 that jets liquid onto the paper M. FIG.

<Liquid injection unit>
The intermediate unit 200c includes a liquid ejecting unit 290 (two first liquid ejecting units 290a in the present embodiment) capable of ejecting liquid containing water onto the front and back of the sheet M in order to suppress deformation of the sheet M such as secondary curling. and a second liquid injection unit 290b). The liquid ejecting unit 290 includes a liquid ejecting head that ejects liquid, and as shown in FIG. The liquid ejecting unit 290 has a first liquid ejecting unit 290a as a first liquid ejecting head at a position facing the front, which is one surface of the paper M, and a first liquid ejecting unit 290a at a position facing the back, which is the other surface of the paper M. A second liquid ejecting unit 290b is arranged as a two-liquid ejecting head. Therefore, the liquid can be jetted onto the front and back surfaces of the sheet of paper M. FIG.
The liquid ejecting head is a line head, and can instantaneously eject the liquid in a straight line in a direction intersecting the conveying direction of the paper M, so that the ejecting time can be increased.

The paper M supplied to the lead-out path 250 equipped with the liquid ejecting unit 290 is transported through the lead-out path 250 by the liquid ejecting unit 290 according to the difference in water content between the front and back sides of the paper M, that is, the paper M When it is determined that the difference in water content between the front and back surfaces of the paper M has reached the determination value, the liquid is jetted to the front and back surfaces of the paper M which have the lower water content. Here, by ejecting the liquid so that the difference in moisture content between the front and back sides of the paper M is within a predetermined range, the secondary curl caused by the difference in drying time due to the difference in moisture content between the front and back sides of the paper M in the transport path 218 can be suppressed. deformation can be suppressed.

In the case of the paper M printed on one side, it is preferable to jet the liquid to the non-printed side (back side) because the water content of the printed side is large. That is, the liquid is jetted to the back surface of the printing surface of the paper M so that the difference in moisture content between the printing surface and the back surface of the paper M is within a predetermined range.
Also, the water content of the ejected liquid may be controlled according to the humidity of the usage environment of the printing unit 100 and the intermediate unit 200 and the water content of the printing surface. For example, when the humidity is lower than a predetermined threshold value and the moisture content of the liquid ejected onto the back surface of the printing surface is equal to or greater than the predetermined threshold value, the moisture content of the ejected liquid is the largest (Condition A). On the other hand, when the humidity is lower than the predetermined threshold value, or when the water content of the liquid ejected onto the back side of the printing surface is equal to or greater than the predetermined threshold value, the water content of the liquid to be ejected increases next to Condition A. Further, when the humidity is equal to or higher than a predetermined threshold and the water content of the liquid to be ejected onto the back side of the printing surface is less than the predetermined threshold, the liquid is not ejected.

Further, when the liquid is jetted onto the back side of the printing surface of the paper M printed on one side, the liquid may be jetted onto the area corresponding to the opposite side of the printed area of the back side, or the liquid may be jetted onto the entire back side. can be Furthermore, the liquid may be sprayed on the back surface in a grid pattern, or may be sprayed on the area or edge of the sheet M that is most affected by the degree of curling.

Further, when the sheet M is divided into a plurality of areas, the determination value for the area to which the corner of the sheet M belongs may be smaller than the determination value for other areas of the sheet M among the plurality of areas. This is because the area belonging to the corner of the paper M undergoes a larger amount of curl deformation (amount of curvature) due to the drying of moisture than other areas of the paper M, and is made smaller than the judgment value of the other areas. Thus, the amount of curl deformation in the area including the corners of the paper M can be reduced.

After that, the paper M onto which the liquid has been jetted is dried while being transported along the transport path 218 and transported to the post-processing unit 300 .

<Method of Operating a Printing Apparatus Equipped with a Liquid Ejecting Unit in an Intermediate Unit>
Next, the operation method of the printing apparatus 1 having the liquid ejecting unit 290 in the intermediate unit 200c will be described. FIG. 19 is a flow chart showing a method of operating a printing apparatus having a liquid ejection unit in an intermediate unit.
First, a print job signal is received from the control unit 10 (step S3-1). Next, an image is printed on the paper M in the printing unit 100 based on the print job signal (step S3-2). The paper M on which the image is printed is conveyed to the intermediate unit 200c having the conveying path 218. As shown in FIG.

After that, the paper M reversed in the reversing path is transferred to the liquid ejection unit 290 (first liquid ejection unit 290a or The liquid is jetted by the second liquid jetting unit 290b) so that the difference in water content between the front and back sides of the paper M is within a predetermined range (for example, 30%).

In step S3-3, it is determined whether or not the difference in water content between the front and back sides is equal to or greater than a determination value (eg, 30%). Since there is no need to jet the liquid to M, it is transported along the transport path 218, transported to the post-processing unit 300, and proceeds to step S3-7.

In step S3-4, the water content on the front side of the paper M is compared with the water content on the back side of the paper M, and if the water content on the front side of the paper M is greater than the water content on the back side of the paper M, "Yes". and proceeds to step S3-5. If the water content on the front side of the paper M is smaller than the water content on the back side of the paper M, the decision is "No", and the process proceeds to step S3-6.

In step S3-5, it is necessary to jet the liquid to the back side of the paper sheet M. Therefore, the second liquid jetting unit 290b sprays the back side of the paper sheet M so that the difference in water content between the front and back sides of the paper sheet M is within a predetermined range. spray liquid on. After that, it is conveyed to the post-processing unit 300 and proceeds to step S3-7.
In step S3-6, since it is necessary to jet the liquid onto the front side of the paper M, the front side of the paper M is sprayed by the first liquid jetting unit 290a so that the difference in water content between the front and back sides of the paper M is within a predetermined range. spray liquid on. After that, it is conveyed to the post-processing unit 300 and proceeds to step S3-7.

In step S3-7, the transported paper M is transported to the stacker 328 via the guide section 330, and placed on the stacker 328 with one side of the paper M aligned. After that, the processing unit 325 performs a punching process for punching holes in the sheets M placed on the stacker 328, a stapling process for binding the sheets M every predetermined number of sheets, and a width direction of the sheets M. Post-processing such as shift processing is performed to adjust the position of the sheet by shifting it in the width direction for each sheet or for each bundle.

As described above, according to the printing apparatus 1 having the liquid ejecting unit 290 in the intermediate unit 200c according to the third embodiment, the following effects can be obtained.
In double-sided printing, the liquid jetting unit 290 provided in the intermediate unit 200c can jet the liquid to the front and back sides of the paper M according to the difference in water content between the front and back sides of the paper M. Even so, it is possible to provide the intermediate unit 200c capable of suppressing curling caused by a difference in drying time between the front and back surfaces of the paper M due to a difference in water content between the front and back surfaces of the paper M. Therefore, when the paper M discharged from the intermediate unit 200c is subjected to post-processing, it is possible to reduce the occurrence of stack failure due to curling of the printed paper M.

In addition, since the liquid jetting unit 290 can jet the liquid onto the paper M so that the difference in moisture content between the front and back sides of the paper M is within a predetermined range, the front and back sides of the paper M can be dried in the same amount of time. Curling can be suppressed.

Further, by setting the determination value of the area to which the corner of the paper M belongs smaller than the determination value of the other area of the paper M, the amount of curl deformation of the area to which the corner of the paper M belongs can be reduced.

Further, since the liquid ejecting unit 290 is provided in the transport path 218, it is possible to reduce the size of the intermediate unit 200c.

Further, since the liquid ejecting unit 290 includes the liquid ejecting head, the liquid can be accurately ejected in a short time so that the difference in moisture content between the front and back surfaces of the paper M is within a predetermined range.

In addition, since the liquid ejecting unit 290 has a first liquid ejecting unit 290a facing one surface of the paper M and a second liquid ejecting unit 290b facing the other surface of the paper M, the paper Liquid can be sprayed on the front and back of M. (Therefore, even if the paper M has a region where the difference in water content between the front and back sides of the paper M is different, it can be dealt with.)

Further, since the liquid ejecting head is a line head, the liquid can be instantaneously ejected in a straight line in the direction intersecting the conveying direction of the paper M, and the ejecting time can be increased.

Further, the printed paper M can be ejected by the liquid ejection unit 290 provided in the transport path 218 so that the difference in moisture content between the front and back sides of the paper M can be kept within a predetermined range. It is possible to suppress the occurrence of curl due to the difference in drying time due to the difference in water content. Therefore, it is possible to provide the post-processing device 2 that reduces the occurrence of stacking defects due to curling of the printed paper M when the paper M is subjected to post-processing.

Further, the printed paper M can be ejected by the liquid ejection unit 290 provided in the transport path 218 so that the difference in moisture content between the front and back sides of the paper M can be kept within a predetermined range. It is possible to suppress the occurrence of curl due to the difference in drying time due to the difference in water content. Therefore, it is possible to provide the printing apparatus 1 that reduces the occurrence of stacking defects due to curling of the printed paper M when the paper M is post-processed.

(Modification 2)
Next, a liquid ejection unit 290 according to Modification 2 of the third embodiment of the present invention will be described.

In the liquid ejection unit 290 according to Modification 2, the position of the liquid ejection unit is different from the position of the liquid ejection unit 290 of the third embodiment, and is upstream of the lead-out path 250 that is part of the transport path 218. are placed.
With this configuration, the transport path 218 downstream of the liquid ejecting unit 290 can be lengthened. It is possible to suppress an increase in the frictional resistance of the paper M due to insufficient drying.

In addition, it is preferable to provide the liquid injection unit 290 in the introduction path 243 further upstream of the branch paths 244 and 245 . By providing the liquid ejecting unit 290 in the introduction path 243, the transport path 218 downstream from the liquid ejecting unit 290 can be made longer, and the drying time of the ejected liquid can be lengthened. An increase in the frictional resistance of the paper M can be further suppressed. Moreover, since only one liquid ejection unit 290 is provided, it is possible to provide a low-cost, small-sized printing apparatus 1 and post-processing apparatus 2 .

Although the intermediate units 200, 200a, 200b, 200c, the post-processing device 2, and the printing device 1 of the present invention have been described above based on the illustrated embodiments, the present invention is not limited to these. The configuration of each part can be replaced with any configuration having similar functions. Also, other optional components may be added to the present invention. Moreover, each embodiment described above may be combined as appropriate. In other words, the drying unit 270, the tensioning mechanism, and the liquid ejection unit 290 may be combined in order to reduce the frictional resistance of the medium and suppress curling due to moisture in the liquid.

REFERENCE SIGNS LIST 1 printing device 2 post-processing device 10 control section 90 drying unit 91 inner path surface 92 outer path surface 93 slit portion 94 curved portion 95 straight portion 96 Giza roller 100 Printing unit 101 Recording apparatus housing 102 Operation unit 103 Paper cassette 103a Grip unit 104 Front plate cover 108 Discharge port 109 Discharge tray 110 Recording Section 111 Recording head 120 Intra-apparatus transport path 131 Transport roller pair 132 Belt transport section 133 Drive roller 134 Driven roller 135 Belt 140 Supply path 141 First supply Path 141a Cover 141b Insertion port 142 Second supply path 142a Pickup roller 143 Third supply path 144 First drive roller pair 145 Separation roller pair 146 Second drive roller Pair 147 Branching mechanism 148 Third drive roller pair 149 Alignment roller pair 150 Ejection path 151 First ejection path 151a Curved reversal path 152 Second ejection path 153 Third Ejection path 154 Common ejection path 155 Ejection port 156 Mounting table 157 Vertical side wall 160 Branch path 161 Branch path roller pair 170 Drawer unit 180 Guide mechanism 199 Conveyance detection Section 200 Intermediate unit 210 Carry-in port 211 Carry-out port 218 Conveyance route 218a Pre-reversal route 218b Post-reversal route 241 First reversing unit 242 Second reversing unit 243 Introduction route 244 First branch route 245 Second branch route 246 First confluence route 247 Second confluence route 248 First reversal route 249 Second reverse route 250 Derivation route 250a... first lead-out path, 250b... second lead-out path, 252... intermediate conveying section, 254... first conveying roller pair, 256... second conveying roller pair, 257... third conveying roller pair, 258... introduction detecting section, 259... Guide flap 261... First regulation flap 262... Second regulation flap 264... First reversal detector 265... First reversal roller pair 267... Second reversal detector 268... Second reversal roller pair , 268a... First roller pair 268b... Second roller pair 269a... First holding part 269b... Second holding part 270... Drying unit 270a... First drying unit 270b... Second drying unit 271... Guide plate 280 Pressure roller 282 Second detector 283 Third detector Parts 284... Fourth detection part 285... Fifth detection part 290... Liquid ejection unit 290a... First liquid ejection unit 290b... Second liquid ejection unit 300... Post-processing unit 319... Downstream transport path , 320 Frame body 322 Post-processing paper feed port 323 Post-processing paper discharge port 325 Processing section 327 Conveying roller pair 328 Stacker 328 a Placement surface 328 b Wall surface 329 Discharge Paper roller pair 330 Guide section 330a Guide surface 331 Discharge tray 335 Downstream transport section 356 Transport detection section L1, L2 Distance P1 First position P2 Second position .

Claims (16)

An intermediate unit having a transport path capable of transporting the medium printed by a printing unit that prints on the medium with liquid based on print data to a post-processing unit that performs post-processing on the medium,
A plurality of reversing paths for reversing the front and back of the medium are provided in the transport path,
A drying unit for promoting drying of the medium is provided in a specific reversing path among the plurality of reversing paths,
determining whether a difference in water content between the front and back sides of the medium after completion of the printing is equal to or greater than a predetermined threshold based on the print data, and driving the drying unit if the difference is equal to or greater than the predetermined threshold;
An intermediate unit characterized by: the medium printed by a printing unit that prints on the medium with liquid based on print data;
An intermediate unit having a transport path capable of transporting the medium to a post-processing unit that performs post-processing on the medium,
The transport path has a plurality of reversing paths for reversing the front and back of the medium,
A drying unit for promoting drying of the medium is provided in a specific reversing path among the plurality of reversing paths,
According to the print data, the medium having a moisture content on the front and back surfaces of the medium equal to or greater than a predetermined threshold is conveyed through the specific reversing route, and the medium having the print data less than the predetermined threshold is conveyed through the specific reversing route. conveying one of the reversing paths of the plurality of reversing paths excluding
An intermediate unit characterized by: 2. It is determined based on the print data whether or not the difference in water content between the front and back sides of the medium is equal to or greater than a predetermined threshold value, and if the difference is equal to or greater than the predetermined threshold value, the drying unit is driven.
intermediate unit as described in . 4. The drying unit includes a first drying unit facing one surface of the medium and a second drying unit facing the other surface of the medium.
An intermediate unit according to any one of Claims 1 to 3 . 5. The intermediate unit according to claim 4, wherein driving of said first drying unit and said second drying unit are independently controlled according to said print data. 6. The intermediate unit according to any one of claims 1 to 5, wherein the drying conditions of the drying unit can be adjusted according to the print data. 7. An intermediate unit as claimed in any preceding claim, wherein the drying unit comprises a blower. The inversion path provided with the blower is configured in a switchback system,
The reversing path is provided with a holding portion that retains the medium that has entered the reversing path downstream of the blower in the direction in which the medium enters the reversing path,
8. The intermediate according to claim 7, wherein the holding unit holds the medium at a portion closer to the rear end side of the medium than to the front end side of the medium in the direction in which the medium enters the reversing path. unit. An intermediate unit having a transport path capable of transporting the medium after completion of printing by a printing unit that prints on the medium with liquid based on print data to a post-processing unit that performs post-processing on the medium after completion of printing. hand,
A reversing path for reversing the front and back of the medium after the completion of the printing is provided in the transport path,
A drying unit is provided in the reversing path for promoting drying of the medium after the completion of the printing,
The drying unit includes a blower,
The inversion path provided with the blower is configured in a switchback system,
The reversing path is provided with a holding portion that retains the medium that has entered the reversing path downstream of the blower in the direction in which the medium enters the reversing path,
The holding unit holds the medium at a portion closer to the rear end side of the medium than to the front end side of the medium in the direction in which the medium enters the reversing path.
An intermediate unit characterized by: In the reversing path, for the medium for which drying by the drying unit is omitted,
10. The intermediate unit according to any one of claims 1 to 9, wherein the switchback is performed upstream of the drying unit in the direction in which the medium enters the reversing path. the medium printed by a printing unit that prints on the medium with liquid based on print data;
An intermediate unit having a transport path capable of transporting the medium to a post-processing unit that performs post-processing on the medium,
The transport path has a reversing path for reversing the front and back of the medium,
A drying unit that accelerates drying of the medium is provided in the reversing path,
In the reversing path, for the medium for which drying by the drying unit is omitted,
switching back upstream of the drying unit in the direction in which the medium enters the reversing path;
An intermediate unit characterized by: the medium printed by a printing unit that prints on the medium with liquid based on print data;
An intermediate unit having a transport path capable of transporting the medium to a post-processing unit that performs post-processing on the medium,
The transport path has a plurality of reversing paths for reversing the front and back of the medium,
A tension applying mechanism that suppresses deformation of the medium by applying tension along the transport path to the medium is provided in a specific reversing path among the plurality of reversing paths,
selecting one of the plurality of reverse paths in response to the print data;
An intermediate unit characterized by: 13. The intermediate unit according to claim 12, wherein the tension applied to the medium is changed according to the print data. 14. An intermediate unit according to claim 12 or 13, wherein said tension applying mechanism has a pressure roller, and said pressure roller applies tension to said medium. A post-processing device for performing post-processing on the medium printed by a printing unit that prints on the medium with a liquid,
the post-processing unit that performs post-processing on the medium;
an intermediate unit according to any one of claims 1 to 14;
A post-processing device comprising: the printing unit for printing on a medium with liquid;
a post-processing unit that performs post-processing on the medium printed by the printing unit;
an intermediate unit according to any one of claims 1 to 14;
A printing device comprising:

Images